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1.
Nat Microbiol ; 9(4): 1075-1088, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38553607

RESUMO

Although vaccines are available for SARS-CoV-2, antiviral drugs such as nirmatrelvir are still needed, particularly for individuals in whom vaccines are less effective, such as the immunocompromised, to prevent severe COVID-19. Here we report an α-ketoamide-based peptidomimetic inhibitor of the SARS-CoV-2 main protease (Mpro), designated RAY1216. Enzyme inhibition kinetic analysis shows that RAY1216 has an inhibition constant of 8.4 nM and suggests that it dissociates about 12 times slower from Mpro compared with nirmatrelvir. The crystal structure of the SARS-CoV-2 Mpro:RAY1216 complex shows that RAY1216 covalently binds to the catalytic Cys145 through the α-ketoamide group. In vitro and using human ACE2 transgenic mouse models, RAY1216 shows antiviral activities against SARS-CoV-2 variants comparable to those of nirmatrelvir. It also shows improved pharmacokinetics in mice and rats, suggesting that RAY1216 could be used without ritonavir, which is co-administered with nirmatrelvir. RAY1216 has been approved as a single-component drug named 'leritrelvir' for COVID-19 treatment in China.


Assuntos
COVID-19 , Vacinas , Humanos , Animais , Camundongos , Ratos , SARS-CoV-2 , Tratamento Farmacológico da COVID-19 , Cinética , Lactamas , Nitrilas , Camundongos Transgênicos
2.
J Control Release ; 368: 275-289, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382812

RESUMO

Virus like particles (VLPs) have been well recognized as one of the most important vaccine platforms due to their structural similarity to natural viruses to induce effective humoral and cellular immune responses. Nevertheless, lack of viral nucleic acids in VLPs usually leads the vaccine candidates less efficient in provoking innate immune against viral infection. Here, we constructed a biomimetic dual antigen hybrid influenza nanovaccines THM-HA@Mn with robust immunogenicity via in situ synthesizing a stimulator of interferon genes (STING) agonist Mn3O4 inside the cavity of a recombinant Hepatitis B core antigen VLP (HBc VLP) having fused SpyTag and influenza M2e antigen peptides (Tag-HBc-M2e, THM for short), followed by conjugating a recombinant hemagglutinin (rHA) antigen on the surface of the nanoparticles through SpyTag/SpyCatcher ligating. Such inside Mn3O4 immunostimulator-outside rHA antigen design, together with the chimeric M2e antigen on the HBc skeleton, enabled the synthesized hybrid nanovaccines THM-HA@Mn to well imitate the spatial distribution of M2e/HA antigens and immunostimulant in natural influenza virus. In vitro cellular experiments indicated that compared with the THM-HA antigen without Mn3O4 and a mixture vaccine consisting of THM-HA + MnOx, the THM-HA@Mn hybrid nanovaccines showed the highest efficacies in dendritic cells uptake and in promoting BMDC maturation, as well as inducing expression of TNF-α and type I interferon IFN-ß. The THM-HA@Mn also displayed the most sustained antigen release at the injection site, the highest efficacies in promoting the DC maturation in lymph nodes and germinal center B cells activation in the spleen of the immunized mice. The co-delivery of immunostimulant and antigens enabled the THM-HA@Mn nanovaccines to induce the highest systemic antigen-specific antibody responses and cellular immunogenicity in mice. Together with the excellent colloid dispersion stability, low cytotoxicity, as well as good biosafety, the synthetic hybrid nanovaccines presented in this study offers a promising strategy to design VLP-based vaccine with robust natural and adaptive immunogenicity against emerging viral pathogens.


Assuntos
Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Vacinas de Partículas Semelhantes a Vírus , Animais , Camundongos , Humanos , Influenza Humana/prevenção & controle , Vacinas de Partículas Semelhantes a Vírus/genética , Imunidade Celular , Adjuvantes Imunológicos , Camundongos Endogâmicos BALB C , Anticorpos Antivirais , Infecções por Orthomyxoviridae/prevenção & controle
3.
Arch Biochem Biophys ; 754: 109917, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395123

RESUMO

As one of the oldest infectious diseases in the world, tuberculosis (TB) is the second most deadly infectious disease after COVID-19. Tuberculosis is caused by Mycobacterium tuberculosis (Mtb), which can attack various organs of the human body. Up to now, drug-resistant TB continues to be a public health threat. Pyrazinamide (PZA) is regarded as a sterilizing drug in the treatment of TB due to its distinct ability to target Mtb persisters. Previously we demonstrated that a D67N mutation in Mycobacterium tuberculosis polynucleotide phosphorylase (MtbPNPase, Rv2783c) confers resistance to PZA and Rv2783c is a potential target for PZA, but the mechanism leading to PZA resistance remains unclear. To gain further insight into the MtbPNPase, we determined the cryo-EM structures of apo Rv2783c, its mutant form and its complex with RNA. Our studies revealed the Rv2783c structure at atomic resolution and identified its enzymatic functional groups essential for its phosphorylase activities. We also investigated the molecular mechanisms underlying the resistance to PZA conferred by the mutation. Our research findings provide structural and functional insights enabling the development of new anti-tuberculosis drugs.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Polirribonucleotídeo Nucleotidiltransferase/genética , Microscopia Crioeletrônica , Amidoidrolases , Testes de Sensibilidade Microbiana , Antituberculosos/farmacologia , Pirazinamida/química , Pirazinamida/uso terapêutico , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Mutação , RNA
4.
Food Chem X ; 21: 101064, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38205158

RESUMO

The aim of this study was to investigate the potential of adding soya bean dregs insoluble dietary fibre (IDF) modified by jet cavitation combined with cellulase to yoghurt to improve its functional properties (Yoghurt was prepared by adding 10 µL of yoghurt fermenter to 100 mL of milk, fermented to pH 4.5 in a constant temperature incubator at 42 °C, and then stored in a refrigerator at 4 °C after adding IDF separately). The results showed that the modified IDF had a rough structure with high water-holding capacity and sodium cholate adsorption capacity. The addition of modified IDF improved the pH, hardness, and elasticity of the yoghurt. During the entire storage period, the titratable acidity and whey precipitation rate of the modified IDF yoghurt gradually increased, and antioxidant activity gradually decreased, and its titratable acidity, whey precipitation rate, and antioxidant activity had a significant advantage compared with those of the blank group yoghurt. In conclusion, the modified soya bean dregs IDF-added yoghurt prepared by jet cavitation combined with the cellulase method has the potential for sodium cholate adsorption capacity and antioxidant activity, which can confer unique functional properties and improve the pH, texture, and reduce whey precipitation of yoghurt. This study provides a scientific basis for the application of soya bean dregs IDF as a fibre fortifier in yoghurt production and suggests innovative ideas for the design of functional dairy products.

5.
J Biomol Struct Dyn ; : 1-14, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37908124

RESUMO

Self-assembling protein nanoparticles showed promise for vaccine design due to efficient antigen presentations and safety. However, the unpredictable formations of epitopes-fused protein assemblies remain challenging in the upstream design. This study suggests employing molecular dynamic (MD) simulations to investigate the assembly properties of Hepatitis B core protein (HBc) from thermodynamic perspectives. Eight HBc derivatives were expressed in E. coli, with their self-assembly properties characterised by high-performance liquid chromatography and transmission electron microscopy. MD simulations on the dimers, based on AlphaFold-predicted 3D structures, analysed the derivative at the atomic level. Results revealed that HBc derivatives can form dissociative polymers or large multi-subunit structures due to assembly failures. The instability of the dimer in aqueous solvents or inappropriate intradimer distances could cause major assembly failures. Polar solvation energies played a vital role too in forming assemble-incompetent dimers. Importantly, our study demonstrated that MD simulations on dimers can provide preliminary predictions on the assembly properties of HBc derivatives, thus aiding vaccine design by lowering the risk of self-assembling failures in engineered proteins.Communicated by Ramaswamy H. Sarma.

6.
Molecules ; 28(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38005362

RESUMO

Heat stress due to high temperatures can cause heat stroke, pyrexia, heat cramps, heart disease, and respiratory diseases, which seriously affect human health. Vitexin has been shown to alleviate heat stress; however, its mechanism of action remains unclear. Therefore, in this study, we used Caco-2 cells to establish a heat stress model and vitamin C as a positive control to investigate the regulatory effects of vitexin on heat-stress-induced apoptosis and the related mechanisms using Cell Counting Kit-8, flow cytometry, real-time quantitative polymerase chain reaction, and Western blot. The results showed that the mRNA expressions of Hsp27, Hsp70, and Hsp90 induced by heat stress could be effectively inhibited at vitexin concentrations as low as 30 µM. After heat stress prevention and heat stress amelioration in model cells based on this concentration, intracellular reactive oxygen species (ROS) levels and the mRNA level and the protein expression of heat shock proteins (Hsp70 and Hsp90) and apoptotic proteins were reduced. In addition, compared with the heat stress amelioration group, the expression of BCL2 mRNA and its protein (anti-apoptotic protein Bcl-2) increased in the heat stress prevention group, while the expression of BAX, CYCS, CASP3, and PARP1 mRNAs and their proteins (apoptotic proteins Bax, Cytochrome C, cle-Caspase-3, and cle-PARP1) were decreased. In summary, the heat-stress-preventive effect of vitexin was slightly better than its heat-stress-ameliorating effect, and its mechanism may be through the inhibition of intracellular ROS levels and thus the modulation of the expressions of Hsp70 and Hsp90, which in turn protects against heat-stress-induced apoptosis. This study provides a theoretical basis for the prevention and amelioration of heat stress using vitexin.


Assuntos
Transtornos de Estresse por Calor , Proteínas de Choque Térmico , Humanos , Espécies Reativas de Oxigênio/metabolismo , Células CACO-2 , Proteína X Associada a bcl-2/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico , Apoptose , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , RNA Mensageiro/metabolismo
7.
Vaccine ; 41(33): 4867-4878, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37391312

RESUMO

Presenting exogenous antigens on virus-like particles (VLPs) through "plug-and-display" decoration strategies based on SpyTag/SpyCatcher isopeptide bonding have emerged as attractive technology for vaccine synthesis. However, whether the position of ligation site in VLPs will impose effects on immunogenicity and physiochemical properties of the synthetic vaccine remains rarely investigated. Here in the present work, the well-established hepatitis B core (HBc) protein was used as chassis to construct dual-antigen influenza nanovaccines, with the conserved epitope peptides derived from extracellular domain of matrix protein M2 (M2e) and hemagglutinin (HA) as target antigens. The M2e antigen was genetically fused to the HBc in the MIR region, together with the SpyTag peptide, which was fused either in the MIR region or at the N-terminal of the protein, so that a recombinant HA antigen (rHA) linked to SpyCatcher can be displayed on it, at two different localizations. Both synthetic nanovaccines showed ability in inducing strong M2e and rHA-specific antibodies and cellular immunogenicity; nevertheless, the one in which rHA was conjugated by N-terminal Tag ligation, was superior to another one synthesized by linking the rHA to MIR region SpyTagged-HBc in all aspects, including higher antigen-specific immunogenicity responses, lower anti-HBc carrier antibody, as well as better dispersion stability. Surface charge and hydrophobicity properties of the two synthetic nanovaccines were analyzed, results revealed that linking the rHA to MIR region SpyTagged-HBc lead to more significant and disadvantageous alteration in physiochemical properties of the HBc chassis. This study will expand our knowledge on "plug-and-display" decoration strategies and provide helpful guidance for the rational design of HBc-VLPs based modular vaccines by using SpyTag/Catcher synthesis.


Assuntos
Hepatite B , Vacinas contra Influenza , Influenza Humana , Vacinas de Partículas Semelhantes a Vírus , Humanos , Animais , Camundongos , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas Sintéticas/genética , Vacinas contra Influenza/genética , Camundongos Endogâmicos BALB C , Antígenos do Núcleo do Vírus da Hepatite B/genética
8.
Food Chem ; 423: 136286, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37178598

RESUMO

In this study, a new composite modification method utilizing a cavitation jet combined with a composite enzyme (cellulase and xylanase) was developed to modify the insoluble dietary fibre (IDF) of okara (IDF was first treated with the cavitation jet at 0.3 MPa for 10 min, and then 6% of the enzyme was added, the composite enzyme with a 1:1 enzyme activity was hydrolysed for 1.5 h to obtain the modified IDF), and explored the structure-activity relationship between the structural properties, physicochemical properties and biological activities of IDF before and after modification. Under the action of cavitation jet and double enzyme hydrolysis, the modified IDF had a wrinkled and loose porous structure, which improved the thermal stability. Its water holding capacity (10.81 ± 0.17 g/g), oil holding capacity (4.83 ± 0.03 g/g) and swelling capacity (18.60 ± 0.60 mL/g) were significantly higher than those of unmodified IDF. In addition, compared with other IDFs, the combined modified IDF had greater advantages in nitrite adsorption (13.75 ± 0.14 µg/g), glucose adsorption (6.46 ± 0.28 mmol/g) and cholesterol adsorption (16.86 ± 0.83 mg/g), and improved in vitro probiotic activity and in vitro anti-digestion rate. The results show that the cavitation jet combined with compound enzyme modification method can effectively improve the economic value of okara.


Assuntos
Fibras na Dieta , Glucose , Fenômenos Químicos , Glucose/química , Hidrólise , Adsorção
9.
Nanoscale Adv ; 5(5): 1433-1449, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36866262

RESUMO

Encapsulating antigens with zeolitic imidazole framework-8 (ZIF-8) exhibits many advantages in vaccine development. However, most viral antigens with complex particulate structures are sensitive to pH or ionic strength, which cannot tolerate harsh synthesis conditions of ZIF-8. Balancing the viral integrity and the growth of ZIF-8 crystals is crucial for the successful encapsulation of these environment-sensitive antigens in ZIF-8. Here, we explored the synthesis of ZIF-8 on inactivated foot and mouth disease virus (known as 146S), which is easily disassociated into no immunogenic subunits under the existing ZIF-8 synthesis conditions. Our results showed that intact 146S could be encapsulated into ZIF-8 with high embedding efficiency by lowering the pH of the 2-MIM solution to 9.0. The size and morphology of 146S@ZIF-8 could be further optimized by increasing the amount of Zn2+ or adding cetyltrimethylammonium bromide (CTAB). 146S@ZIF-8 with a uniform diameter of about 49 nm could be synthesized by adding 0.01% CTAB, which was speculated to be composed of single 146S armored with nanometer-scale ZIF-8 crystal networks. Plenty of histidine on the 146S surface forms a unique His-Zn-MIM coordination in the near vicinity of 146S particles, which greatly increases the thermostability of 146S by about 5 °C, and the nano-scale ZIF-8 crystal coating exhibited extraordinary stability to resist EDTE-treatment. More importantly, the well-controlled size and morphology enabled 146S@ZIF-8(0.01% CTAB) to facilitate antigen uptake. The immunization of 146S@ZIF-8(4×Zn2+) or 146S@ZIF-8(0.01% CTAB) significantly enhanced the specific antibody titers and promoted the differentiation of memory T cells without adding another immunopotentiator. This study reported for the first time the strategy of the synthesis of crystalline ZIF-8 on an environment-sensitive antigen and demonstrated that the nano-size and appropriate morphology of ZIF-8 are crucial to exert adjuvant effects, thus expanding the application of MOFs in vaccine delivery.

10.
Food Funct ; 14(6): 2568-2585, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36857725

RESUMO

Nattokinase (NK) is an alkaline serine protease with strong thrombolytic activity produced by Bacillus spp. or Pseudomonas spp. It is a potential therapeutic agent for thrombotic diseases because of its safety, economy, and lack of side effects. Herein, a comprehensive summary and analysis of the reports surrounding NK were presented, and the physical-chemical properties and producers of NK were first described. The process and mechanism of NK synthesis were summarized, but these are vague and not specific enough. Further results may be achieved if detection techniques such as multi-omics are used to explore the process of NK synthesis. The purification of NK has problems such as a complicated operation and low recovery rate, which were found when summarizing the techniques to improve the quality of finished products. If multiple simple and efficient precipitation methods and purification materials are combined to purify NK, it may be possible to solve the current challenges. Additionally, the application potential of NK in biomedicine was reviewed, but functional foods with NK are challenging for acceptance in daily life due to their unpleasant odor. Accordingly, multi-strain combination fermentation or food flavoring agents can improve the odor of fermented foods and increase people's acceptance of them. Finally, the possible future directions focused on NK studies were proposed and provided suggestions for subsequent researchers.


Assuntos
Bacillus , Trombose , Humanos , Trombose/tratamento farmacológico , Subtilisinas/química , Fibrinolíticos
11.
Int J Pharm ; 625: 122083, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-35934167

RESUMO

Maintaining structural integrity and enhancing stability of inactivated foot-and-mouth disease virus (iFMDV) antigen in adjuvants is crucial to ensure the vaccine potency. Unfortunately, formulation with most reported adjuvants leads to the accelerated dissociation of iFMDV into inactive pentamers. Here, an ionic liquid, i.e., choline and niacin ([Cho][Nic]), which was found to stabilize iFMDV against the acid- and thermo- induced dissociation in buffer solution, was applied to construct a novel oil-in-ionic liquid (o/IL) nanoemulsion adjuvant composed of [Cho][Nic], squalene, and Tween 80. The o/IL nanoemulsion formulated with iFMDV has a monodisperse diameter of 135.8 ± 40.4 nm. The thermostability and long-term stability of iFMDV were remarkably enhanced in o/IL nanoemulsion compared with that in the o/w emulsion without [Cho][Nic] and in the commercial Montanide ISA 206 adjuvant. The o/IL nanoemulsion exerted its adjuvant effects by improving the humoral immune responses. Immunization of o/IL nanoemulsion adjuvanted iFMDV induced specific IgG titers similar to that adjuvanted by Montanide ISA 206 and about 4-fold higher than the un-adjuvanted iFMDV, also promoted the activation of B lymphocytes and the secretion of interleukin-4 in the mice model. This [Cho][Nic]-based o/IL nanoemulsion can serve as a promising adjuvant platform for the foot-and-mouth disease vaccine.


Assuntos
Vírus da Febre Aftosa , Líquidos Iônicos , Vacinas Virais , Adjuvantes Imunológicos/química , Adjuvantes Farmacêuticos , Animais , Anticorpos Antivirais , Antígenos Virais , Imunidade Humoral , Camundongos , Óleo Mineral
12.
Foods ; 11(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35954017

RESUMO

In order to clarify the effect of a high pressure/heating combination on the texture of Chinese traditional pig trotter with soy sauce, textural parameters (springiness, chewiness, hardness, and gumminess), the secondary structures, cross-links, decorin (DCN), glycosaminoglycans (GAGs) levels, and the histochemical morphology of collagen fibers under different treatments (0.1 MPa, 150 MPa, 300 MPa, 0.1 MPa + 50 °C, 150 MPa + 50 °C, and 300 MPa + 50 °C) were assessed. At room temperature, the 150 and 300 MPa treatments increased the hardness and chewiness of the pig trotter with weak denaturation of collagen proteins compared with the control group. Textural parameters were improved at 300 MPa + 50 °C, accompanied by an ultrastructural collapse of collagen fibers, the reduction in cross-links, DCN and GAGs levels, and unfolded triple-helix structure. We concluded that the positive effects on the textural parameters of pig trotters by a combination of treatments could be attributed to the collapse of collagen structure.

13.
Ann Transl Med ; 10(8): 480, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35571388

RESUMO

Background: Proton pump inhibitors (PPIs) have been recommended as standard of care for reflux esophagitis (RE). Vonoprazan (VPZ), a novel potassium-competitive acid blocker (P-CAB), has been approved in China after demonstrating clinical benefit in RE. However, there are not any published literature reported the cost-effectiveness of VPZ compared with PPI in Chinese healthcare setting. Thus, this study aimed to estimate the cost-effectiveness of VPZ compared with PPIs for the treatment of RE patients in China and take advantage of this result to inform healthcare decision-making. Methods: A Markov model was developed to predict the effectiveness and costs of VPZ for 4 weeks and PPI group for 8 weeks in RE treatment over a 5-year time horizon from a healthcare system perspective. Four health states within healing and maintenance phases were defined in the model: mucosa healed, mucosa unhealed, relapse, and death. Transition probabilities including healing rate and relapse rate were derived from a single-arm meta-analysis and mortality were obtained from Chinese life table. Drug costs and other medical expenses were retrieved from China tendering prices and local clinical expert estimation. Utility parameters were derived from published literature. Both health outcomes and costs were discounted at a rate of 5% annually. Quality-adjusted life years (QALYs), direct medical costs and incremental cost-effectiveness ratios were evaluated. Uncertainty was assessed by one-way and probabilistic sensitivity analysis (PSA). Results: The healing rate for VPZ and PPI were 90% (95% CI: 82-97%) and 74% (95% CI: 71-76%) at week 4 respectively and were 94% (95% CI: 88-99%) and 87% (95% CI: 85-88%) at week 8 respectively. Treatment with VPZ resulted in 4.35 QALYs at a total cost of USD 1,354 over 5 years. Compared with the PPI group, treating RE with VPZ was associated with 0.02 QALYs gained and a cost saving of USD 943. Thus, VPZ should be considered as the dominant treatment option. The model results were deemed robust in sensitivity analyses. Conclusions: VPZ generates incremental QALYs at a lower cost compared with PPI, thus could be considered as an optional choice in the treatment of patients with RE.

14.
J Control Release ; 346: 380-391, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35483639

RESUMO

Effective antigen delivery and immune stimulation in nasal mucosa determine the success of mucosal immunity. Here, an oil-in-ionic liquid (o/IL) nanoemulsion formulated with choline and niacin IL ([Cho][Nic]), squalene, and Tween 80 surfactant is explored as a vaccine delivery system for intranasal mucosal immunization. Compared to the o/w emulsion counterpart without the ILs, the o/IL manoemulsion showed a reduced and more uniform size of approximately 168 nm and significantly improved stability. Studies in mice model showed that when was used as an intranasal vaccine delivery system for influenza split-virus antigens, the antigens in the o/IL nanoemulsion induced strong mucosal immune responses with secretory IgA titers 25- and 5.8-fold higher than those of naked and commercial MF59-adjuvanted antigens, respectively. The o/IL nanoemulsion system also induced stronger systemic humoral responses. The excellent mucosal adjuvant effects of the o/IL nanoemulsion mainly benefited from the prolonged retention of antigens in the nasal cavity, enhanced antigen permeation into the submucosa, and the consequently promoted proliferation of CD11b cells and CD4+ T cells in nasal mucosa-associated lymphoid tissue. Moreover, when used as an injection adjuvant, the o/IL nanoemulsion also induced stronger humoral immune responses than MF59. Thus, the [Cho][Nic]-based o/IL nanoemulsion vaccine delivery system can serve as a promising adjuvant platform.


Assuntos
Vacinas contra Influenza , Influenza Humana , Líquidos Iônicos , Adjuvantes Imunológicos , Administração Intranasal , Animais , Anticorpos Antivirais , Antígenos Virais , Humanos , Imunidade nas Mucosas , Camundongos , Camundongos Endogâmicos BALB C
15.
Front Psychol ; 12: 794500, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925195

RESUMO

English as a verb-medial language has a short-before-long preference, whereas Korean and Japanese as verb-final languages show a long-before-short preference. In second language (L2) research, little is known regarding how L1 processing strategies affect the ultimate attainment of target structures. Existing work has shown that native speakers of Chinese strongly prefer to utter demonstrative-classifier (DCL) phrases first in subject-extracted relatives (DCL-SR-N) and DCLs second in object-extracted relatives (OR-DCL-N). But it remains unknown whether L2 learners with typologically different language backgrounds are able to acquire native-like strategies, and how they deviate from native speakers or even among themselves. Using a phrase-assembly task, we investigated advanced L2-Chinese learners whose L1s were English, Korean, and Japanese, because English lacks individual classifiers and has postnominal relative clause (RC), whereas Korean and Japanese have individual classifiers and prenominal RCs. Results showed that the English and Korean groups deviated from the native controls' asymmetric pattern, but the Japanese group approximated native-like performance. Furthermore, compared to the English group, the Korean and Japanese groups favored the DCL-second configuration in SRs and ORs. No differences were found between the Korean and Japanese groups. Overall, our findings suggest that L1 processing strategies play an overarching role in L2 acquisition of asymmetric positioning of DCLs in Chinese RCs.

16.
Front Public Health ; 9: 704889, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34490187

RESUMO

Objective: To evaluate the cost effectiveness of vedolizumab vs. infliximab in the treatment of anti-tumor necrosis factor-alpha (TNF-α)-naïve patients with moderate-to-severe active ulcerative colitis (UC) in China. Methods: The costs and effectiveness of vedolizumab and infliximab in the treatment of anti-TNF-α naïve patients with moderate-to-severe active UC were compared using a hybrid decision tree model and a Markov model. From the perspective of the Chinese healthcare system, this study simulated the lifetime health benefits [quality-adjusted life-years (QALYs)] and costs (USD) for patients with UC from the induction phase to the maintenance phase, with an annual discount rate of 5%. The clinical efficacy and transition probability data were based on a previously published network meta-analysis. The health utility, surgical risk, biologic drug discontinuation rate, and mortality were derived from previous literature and the Chinese statistical yearbook. The cost data were based on China's drug purchase and biding platform and the results of a survey sent to clinicians in 18 tertiary hospitals. One-way and probabilistic sensitivity analyses (PSAs) were performed to validate the robustness of the models' assumptions and specific parameter estimates. Results: The results of the base-case analyses showed that compared with infliximab, vedolizumab led to a gain of 0.25 QALYs (9.56 vs. 9.31 QALYs) and was less expensive by $7,349 ($180,138 vs. 187,487), indicating that the use of vedolizumab was a dominant strategy. The results of one-way sensitivity analyses suggested that the annual discount rate and health-state costs had the greatest impact, but the results were otherwise consistent with those of the base-case analyses. The PSAs suggested that vedolizumab had a 98.6% probability of being effective at a threshold of 3 times the gross domestic product (GDP) per capita in China in 2020. Conclusion: Compared with infliximab, vedolizumab appears to be a more cost-effective option in the treatment of anti-TNF-α naïve adult patients with moderate-to-severe, active UC in China.


Assuntos
Colite Ulcerativa , Inibidores do Fator de Necrose Tumoral , Adulto , Anticorpos Monoclonais Humanizados , China , Colite Ulcerativa/tratamento farmacológico , Análise Custo-Benefício , Humanos , Infliximab/uso terapêutico , Fator de Necrose Tumoral alfa
17.
Biomaterials ; 276: 121035, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34303153

RESUMO

Virus-like particles (VLPs) holding internal cavity with diameter from tens up to one hundred nanometers are attractive platform for drug delivery. Nevertheless, the packing of drugs in the nanocage mainly relies on complicated disassembly-reassembly process. In this study, hepatitis B core protein (HBc) VLPs which can withstand temperature up to 90 °C was employed as carrier to load a lipophilic near infrared dye IR780. It was found that an attaching-dis-atching-diffusing process was involved for the entering of IR780 in the cavity of HBc. The first two steps were associated with the electrostatic interactions between oppositely charged HBc and IR780, which was critically manipulated by ionic strength and HBc/IR780 mass ratio at which they were mixed; while the diffusion of IR780 across the shell of HBc showed a temperature-dependent manner that can be triggered by thermal induced pore-opening of the HBc capsid. At optimized condition, about 1055 IR780 molecules were encapsulated in each HBc by simply mixing them for 10 min at 60 °C. Compared with free IR780, the HBc-IR780 particles showed significantly improved aqueous and photostability, as well as enhanced photothermal and photodynamic performance for cancer therapy. This study provides a novel drug loading strategy and nanomemedicine for cancer phototherapies.


Assuntos
Hepatite B , Neoplasias , Hepatite B/terapia , Humanos , Indóis , Concentração Osmolar , Fototerapia
18.
Adv Ther ; 38(8): 4233-4245, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34089502

RESUMO

INTRODUCTION: To compare the cost-effectiveness of vedolizumab with that of conventional therapy in patients with moderate-to-severe active Crohn's disease (CD) in China. METHODS: A decision tree and Markov model were built to predict the lifetime cost and health outcomes in the induction phase and maintenance phase of vedolizumab treatment and conventional therapy (a combination of corticosteroids, immunosuppressants, and aminosalicylates) in adult patients with moderate-to-severe active CD from the perspective of China's healthcare system. Clinical efficacy and health utility were derived from the GEMINI 2 and GEMINI 3 trials and published literature. Costs were mainly obtained from clinical physician surveys in China and are presented in 2020 US dollars. Health outcomes (quality-adjusted life years, QALYs) and costs were discounted at an annual rate of 5%. The incremental cost per QALY gained was used to compare the cost-effectiveness of the two treatments. One-way and probabilistic sensitivity analyses (PSAs) were performed to test the robustness of the model. RESULTS: The model predicted more QALYs (9.92 vs 9.00 QALYs) and lower incurred costs ($288,284 vs $309,680) in vedolizumab than in conventional therapy in a mixed population (anti-TNF-naïve and anti-TNF-failure populations) over a lifetime horizon in the base-case analysis. Similar results were observed in the anti-TNF-naïve and anti-TNF-failure subgroups of patients with CD. One-way sensitivity analysis results suggested that health state cost was the most influential factor in the model. The PSA results supported the dominance of vedolizumab in the base-case analysis. CONCLUSION: Vedolizumab appears to be a cost-effective strategy option in the treatment of adult patients with moderate-to-severe active CD in China in both anti-TNF-naïve and anti-TNF-failure populations.


Assuntos
Doença de Crohn , Adulto , Anticorpos Monoclonais Humanizados , China , Análise Custo-Benefício , Doença de Crohn/tratamento farmacológico , Humanos , Modelos Econômicos , Anos de Vida Ajustados por Qualidade de Vida , Inibidores do Fator de Necrose Tumoral
19.
Onco Targets Ther ; 13: 10995-11006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149614

RESUMO

BACKGROUND: Zeaxanthin, a carotenoid commonly found in plants, has a variety of biological functions including anti-cancer activity. PURPOSE: This study aimed to investigate the potential mechanisms of zeaxanthin in human gastric cancer cells. METHODS: CCK-8 assay was used to examine the cytotoxic effect of zeaxanthin on human gastric cancer cells. Flow cytometry was used to analyse AGS cell cycle distribution and apoptosis status. Western blot analysis was used to detect the expression levels of cycle-related proteins (Cyclin A, Cyclin B1, CDK1/2, p21, and p27), apoptosis-related proteins (Bcl-2, Bad, caspase-3, PARP), MAPK, AKT, STAT3, and NF-κB. RESULTS: CCK-8 assay showed that zeaxanthin has obvious cytotoxic effects on 12 types of human gastric cancer cells, but no obvious toxic effect on normal cells. In addition, flow cytometry and Western blotting results showed that zeaxanthin induces apoptosis by reducing mitochondrial membrane potential; increasing Cytochrome C, Bax, cleaved-caspase-3 (cle-cas-3), and cleaved-PARP (cle-PARP) expression levels; and decreasing Bcl-2, pro-caspase-3 (pro-cas-3), and pro-PARP expression levels. Additionally, zeaxanthin caused cell cycle arrest at the G2/M phase by increasing the levels of p21 and p27 and reduced the levels of AKT, Cyclin A, Cyclin B1, and Cyclin-dependent kinase 1/2 (CDK1/2). Furthermore, after zeaxanthin treatment, the expression levels of reactive oxygen species (ROS), p-JNK, p-p38, and I-κB increased, and the expression levels of p-ERK, p-AKT, STAT3, and NF-κB decreased. However, the ROS scavenger N-acetylcysteine (NAC) and MAPK inhibitors inhibited zeaxanthin-induced apoptosis, and under the action of zeaxanthin, MAPK regulated NF-κB and STAT3, and reduced their protein expression levels. CONCLUSION: Zeaxanthin has a potential effect against gastric cancer cells through the ROS-mediated MAPK, AKT, NF-κB, and STAT3 signaling pathways, and it is expected to become a new drug for the treatment of human gastric cancer.

20.
Food Sci Nutr ; 8(6): 2882-2894, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32566206

RESUMO

Metabolomic studies were carried out using gas chromatography and mass spectrometry (GC-MS) on Daohuaxiang variety rice (Oryza sativa L.) from the Wuchang Geographical Indication Rice Protection Area in Heilongjiang Province, to investigate the effects of storage on brown rice metabolism. The data were subjected to principal component analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA), and cluster analysis using software such as SIMCA. Analysis of the samples led to the identification of a total of 160 metabolites. No significant differences were found in the amount of metabolites before and after storage. A total of 31 differential metabolites were screened, and the changes in metabolite content showed a "reverse change" overall. Storage significantly changed the content of various metabolites in rice, with fatty acids impacted most significantly. Metabolic pathway analysis revealed that fatty acid biosynthesis is a key metabolic pathway in rice storage. The degradation of brown rice quality caused by storage is closely related to the composition and content of its metabolites, and that change in lipid content significantly affects brown rice quality during storage.

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