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1.
Open Forum Infect Dis ; 11(9): ofae506, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39319090

RESUMO

Background: Recurrent Clostridioides difficile infection (CDI) is a critical clinical issue due to the increase in incidence and difficulty in treatment. We aimed to identify gut microbial and metabolic features associated with disease recurrence in a group of pediatric CDI patients. Methods: A total of 84 children with primary CDI were prospectively enrolled in the study. Fecal samples collected at the initial diagnosis were subjected to 16S rRNA gene sequencing and targeted metabolomics analysis to profile the bacterial composition and metabolome. Results: Twenty-six of 84 (31.0%) pediatric CDI patients experienced recurrence. The alpha diversity of the fecal microbiota was significantly lower in the recurrent group than in the nonrecurrent group, and the beta diversity was different from that of the nonrecurrent group. Taxonomic profiles revealed that the relative abundances of multiple bacterial taxa significantly differed between the recurrent and nonrecurrent groups. Linear discriminant analysis effect size analysis identified several bacterial genera that discriminated between recurrent and nonrecurrent groups, including Parabacteroides, Coprococcus, Dialister, and Clostridium. Recurrent bacteria presented lower abundances of several short-chain fatty acid (SCFA)-producing bacteria (Faecalibacterium, Butyricicoccus, Clostridium, Roseburia, and Ruminococcus), which were correlated with reduced fecal SCFA levels. In addition, several bile acids, including lithocholic acid (LCA), 12-ketoLCA, trihydroxycholestanoic acid, and deoxycholic acid, were decreased in recurrent patients. Conclusions: Our study suggests that the differing gut microbiota profiles in pediatric CDI patients may contribute to disease recurrence by modulating SCFA concentrations and bile acid profiles. The gut microbiota and metabolite signatures may be used to predict disease recurrence in children with CDI.

2.
Chemosphere ; 366: 143369, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39307470

RESUMO

The efficiency and stability of the electrical activation of persulfate (PS) by transition metal-based cathode are controlled by the cycling of Fe(III)/Fe(II) and the mass transfer of PS. In this study, the mixed-valence MOFs catalyst (FeII-MIL-53(Fe)) modified flow-through cathode was prepared for the first time. FeII-MIL-53(Fe) was prepared by replacing part of the iron-oxygen network structure in MIL-53(Fe) with Fe(II), resulting in the formation of coordinated unsaturated iron centers (CUICs). The increase of the Fe(III) CUICs facilitated the conversion of Fe(III) to Fe(II). Furthermore, the cycling of Fe(III)/Fe(II) was further promoted by the electric field. Meanwhile, the hydrodynamic behavior of flow-through cathode was indicated by the computational fluid dynamics (CFD) simulation. The quenching experiments and electron paramagnetic resonance (EPR) results showed that several reactive specie (SO4·-, ·OH, O2·- and 1O2) were produce. In summary, this work provided an effective strategy for the efficient and stable electrical activation of PDS.

3.
J Radiat Res ; 65(5): 591-602, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39154379

RESUMO

A Monte Carlo simulation was used to assess the performance of a collimated hollow X-ray microbeam for subcellular cytoplasm irradiation. A high-Z coaxial collimation structure with an inner core for nucleus shielding was investigated. Two key performances, the extraction efficiency (cytoplasm dose per unit incident fluence) and the dose contrast (cytoplasm-to-nucleus dose ratio), were evaluated regarding the influences of the material, geometry and physical arrangements of the collimator, target dish and incident beam source. Simulation results demonstrate that a gold coaxial structure with a practical collimation geometry of a 1-mm length, 10-µm inner diameter and 200-µm outer diameter, with the top exit closely attached (with a minimized air gap) to the bottom of a cell dish with a 3-µm thick Mylar film is recommended for cytoplasm irradiation of adherent mammalian cells. For a synchrotron source in the energy range < 10 keV, a dose contrast of approximately 100 can be achieved. For a bremsstrahlung source <30-kV tube voltage, a dose contrast of approximately 50-100 can still be achieved. General principles are summarized with further explanations of the performance of the hollow X-ray microbeam.


Assuntos
Citoplasma , Método de Monte Carlo , Citoplasma/efeitos da radiação , Raios X , Simulação por Computador , Humanos , Animais
4.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(3): 271-276, 2024 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-38863092

RESUMO

In order to improve the biological effect of proton therapy, the authors first propose a new method of boron-based proton-enhanced radiotherapy in a " ternary " radiotherapy mode, based on the existing sensitizing effect of proton radiotherapy: i.e, Boron-based mediators (11B and 10B) induce the proton-hydrogen-boron fusion reaction of the low-energy protons arriving at the Bragg peak region of the tumor target area (p+11B→3α) and thermal neutron capture (10B+n→7Li3+(0.84 MeV)+4He2+(1.47 MeV)+γ(0.477 MeV)), which release low-energy α-particles with high LETs to enhance the biological effect of proton dose in the target area, thus improve the clinical effect of proton therapy. Then, the advantages and disadvantages of the "ternary" model were analyzed from the theoretical basis and current research status, and finally, the "ternary" model is summarized and prospected.


Assuntos
Terapia com Prótons , Prótons , Boro , Neoplasias/radioterapia , Dosagem Radioterapêutica , Partículas alfa/uso terapêutico , Modelos Teóricos
5.
Sci Total Environ ; 944: 173839, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38871317

RESUMO

The persulfate-based electrochemical advanced oxidation processes (PS-EAOPs) exhibit distinctive advantages in the degradation of emerging contaminants (ECs) and have garnered significant attention among researchers, leading to a consistent surge in related research publications over the past decade. Regrettably, there is still a lack of a critical review gaining deep into understanding of ECs degradation by PS-EAOPs. To address the knowledge gaps, in this review, the mechanism of electro-activated PS at the interface of the electrodes (anode, cathode and particle electrodes) is elaborated. The correlation between these electrode materials and the activation mechanism of PS is systematically discussed. The strategies for improving the performance of electrode material that determining the efficiency of PS-EAOPs are also summarized. Then, the applications of PS-EAOPs for the degradation of ECs are described. Finally, the challenges and outlook of PS-EAOPs are discussed. In summary, this review offers valuable guidance for the degradation of ECs by PS-EAOPs.

6.
Front Pediatr ; 12: 1369823, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38783921

RESUMO

Background and purpose: Autism spectrum disorder (ASD) is a group of heterogeneous neurodevelopmental disorders that is characterized by core features in social communication impairment and restricted, repetitive sensory-motor behaviors. This study aimed to further investigate the utilization of fecal microbiota transplantation (FMT) in children with ASD, both with and without gastrointestinal (GI) symptoms, evaluate the effect of FMT and analyze the alterations in bacterial and fungal composition within the gut microbiota. Methods: A total of 38 children diagnosed with ASD participated in the study and underwent oral lyophilized FMT treatment. The dosage of the FMT treatment was determined based on a ratio of 1 g of donor stool per 1 kg of recipient body weight, with a frequency of once every 4 weeks for a total of 12 weeks. In addition, 30 healthy controls (HC) were included in the analysis. The clinical efficacy of FMT was evaluated, while the composition of fecal bacteria and fungi was determined using 16S rRNA and ITS gene sequencing methods. Results: Median age of the 38 children with ASD was 7 years. Among these children, 84.2% (32 of 38) were boys and 81.6% (31 of 38) exhibited GI symptoms, with indigestion, constipation and diarrhea being the most common symptoms. Sample collections and assessments were conducted at baseline (week 0), post-treatment (week 12) and follow-up (week 20). At the end of the follow-up phase after FMT treatment, the autism behavior checklist (ABC) scores decreased by 23% from baseline, and there was a 10% reduction in scores on the childhood autism rating scale (CARS), a 6% reduction in scores on the social responsiveness scale (SRS) and a 10% reduction in scores on the sleep disturbance scale for children (SDSC). In addition, short-term adverse events observed included vomiting and fever in 2 participants, which were self-limiting and resolved within 24 h, and no long-term adverse events were observed. Although there was no significant difference in alpha and beta diversity in children with ASD before and after FMT therapy, the FMT treatment resulted in alterations in the relative abundances of various bacterial and fungal genera in the samples of ASD patients. Comparisons between children with ASD and healthy controls (HC) revealed statistically significant differences in microbial abundance before and after FMT. Blautia, Sellimonas, Saccharomycopsis and Cystobasidium were more abundant in children with ASD than in HC, while Dorea were less abundant. After FMT treatment, levels of Blautia, Sellimonas, Saccharomycopsis and Cystobasidium decreased, while levels of Dorea increased. Moreover, the increased abundances of Fusicatenibacter, Erysipelotrichaceae_UCG-003, Saccharomyces, Rhodotorula, Cutaneotrichosporon and Zygosaccharomyces were negatively correlated with the scores of ASD core symptoms. Conclusions: Oral lyophilized FMT could improve GI and ASD related symptoms, as well as sleep disturbances, and alter the gut bacterial and fungal microbiota composition in children with ASD. Clinical Trial Registration: Chinese Clinical Trial Registry, ChiCTR2200055943. Registered 28 January 2022, www.chictr.org.cn.

7.
J Food Sci ; 89(5): 3078-3093, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38605580

RESUMO

Human milk contains a variety of microorganisms that exert benefit for human health. In the current study, we isolated a novel Lactobacillus gasseri strain named Lactobacillus gasseri (L. gasseri) SHMB 0001 from human milk and aimed to evaluate the probiotic characteristics and protective effects on murine colitis of the strain. The results showed that L. gasseri SHMB 0001 possessed promising potential probiotic characteristics, including good tolerance against artificial gastric and intestinal fluids, adhesion to Caco-2 cells, susceptibility to antibiotic, no hemolytic activity, and without signs of toxicity or infection in mice. Administration of L. gasseri SHMB 0001 (1 × 108 CFU per gram of mouse weight per day) reduced weight loss, the disease activity index, and colon shortening in mice during murine colitis conditions. Histopathological analysis revealed that L. gasseri SHMB 0001 treatment attenuated epithelial damage and inflammatory infiltration in the colon. L. gasseri SHMB 0001 treatment increased the expression of colonic occludin and claudin-1 while decreasing the expression of pro-inflammatory cytokine genes. L. gasseri SHMB 0001 modified the composition and structure of the gut microbiota community and partially recovered the Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways altered by dextran sulfate sodium (DSS). Overall, our results indicated that the human breast milk-derived L. gasseri SHMB 0001 exhibited promising probiotic properties and ameliorative effect on DSS-induced colitis in mice. L. gasseri SHMB 0001 may be applied as a promising probiotic against intestinal inflammation in the future. PRACTICAL APPLICATION: L. gasseri SHMB 0001 isolated from human breast milk showed good tolerance to gastrointestinal environment, safety, and protective effect against DSS-induced mice colitis via enforcing gut barrier, downregulating pro-inflammatory cytokines, and modulating gut microbiota. L. gasseri SHMB 0001 may be a promising probiotic candidate for the treatment of intestinal inflammation.


Assuntos
Colite , Sulfato de Dextrana , Microbioma Gastrointestinal , Lactobacillus gasseri , Leite Humano , Probióticos , Probióticos/farmacologia , Animais , Humanos , Camundongos , Colite/induzido quimicamente , Colite/terapia , Colite/microbiologia , Sulfato de Dextrana/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Células CACO-2 , Feminino , Colo/microbiologia , Colo/patologia , Colo/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças
8.
Cancer Biol Ther ; 25(1): 2320307, 2024 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-38385627

RESUMO

Colorectal cancer (CRC) is a malignancy with high incidence and poor prognosis. It is urgent to identify valuable biomarkers for early diagnosis and potent therapeutic targets. It has been reported that SATB1 is associated with the malignant progression in CRC. To explore the role of SATB1 in CRC progression and the underlying mechanism, we evaluated the expression of SATB1 in the paired CRC tissues with immunohistochemistry. The results showed that the expression of SATB1 in lymph node metastasis was higher than that in primary lesion, and that in distant organ metastasis was higher than that in primary lesion. The retrospective analysis showed that patients with high expression of SATB1 had a significantly worse prognosis than those with negative and moderate expression. In vitro experiments that employing SATB1 over-expressing and depleted CRC cell lines confirmed that SATB1 contributes to cell proliferation and colonization, while inhibiting cell motility. Furthermore, the tissue immunofluorescence assay, Co-IP and Western blot were conducted to reveal that SATB1 induced translocation of ß-catenin and formed a protein complex with it in the nuclei. In conclusion, SATB1 mediated tumor colonization and ß-catenin nuclear localization are associated with the malignant progression and poor prognosis of CRC.


Assuntos
Neoplasias Colorretais , Proteínas de Ligação à Região de Interação com a Matriz , Humanos , beta Catenina/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Ligação à Região de Interação com a Matriz/genética , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Estudos Retrospectivos , Prognóstico , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Via de Sinalização Wnt
9.
Infect Drug Resist ; 17: 329-339, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38293314

RESUMO

Background: Our previous study reported a high rate of recurrence in children with Clostridioides difficile (C. difficile) infection (CDI) after conventional antibiotic therapy. Here, we aimed to explore whether metronidazole and vancomycin resistant C. difficile isolates are circulating in pediatric CDI. Methods: Antimicrobial susceptibility testing (AST) using the agar dilution method according to the Clinical and Laboratory Standard Institute (CLSI) were performed on C. difficile isolates collected from children with CDI between 2019 and 2022 at the Shanghai Children's Hospital. Whole-genome sequencing (WGS) was performed on all C. difficile isolates, and the presence of antibiotic resistance genes (ARGs) were identified using Resfinder and the Comprehensive Antibiotic Resistance Database (CARD). The presence of plasmid pCD-METRO was detected using SRST2 (v0.2.0) against 8 pCD-METRO coding sequences. Results: A total of 50 C. difficile isolates were collected from stools of CDI children. The overall resistance rate on all isolates was 30.00% for metronidazole, 6.00% for vancomycin, 0% for rifaximin, 2.00% for rifampin, 24.00% for meropenem, 100.00% for ceftriaxone and clindamycin, 86.00% for erythromycin, 30.0% for levofloxacin, and 50.0% for tetracycline. Multidrug-resistant (MDR) was presented in 44 isolates (88.00%). Sixteen reported potential ARGs relating with resistance to antibiotic classes of aminoglycoside (AAC(6')-Ie-APH(2")-Ia, aad(6), ANT(6)-Ib, APH(2")-If, APH(3')-IIIa), lincosamide-clindamycin-erythromycin (ErmB, ErmQ), fluoroquinolones (CdeA), glycopeptides (vanRG), nucleoside (SAT-4), tetracycline (tetM, tetA(P), tetB(P), tetO), and trimethoprim (dfrF) were identified. However, the pCD-METRO plasmid and vanA/B were not detected in any isolates. Conclusion: C. difficile isolates from children with reduced susceptibility to metronidazole and vancomycin are emerging in pediatric CDI in China. The lack of pCD-METRO plasmid and vanA/B associated with reduced antibiotic susceptibility suggests there are additional mechanisms of resistance.

10.
Eur J Histochem ; 67(4)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38112591

RESUMO

Osteoarthritis (OA) is characterized by degenerative articular cartilage. Nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) plays an important role in inflammation. This study aims to investigate whether protective effects of curculigoside on OA are medicated by the regulation of NLRP3 pathway. Destabilization of the medial meniscus (DMM) was performed to build an OA mouse model. After surgery, OA mice were treated with curculigoside. Immunohistochemistry was conducted to evaluate OA cartilage. In addition, human chondrocytes were isolated and treated with curculigoside. The mRNA and protein expression of iNOS, MMP-9, NLRP3 was detected by PCR and Western blot analysis. Curculigoside inhibited mRNA and protein levels of iNOS and MMP-9 induced by DMM surgery in a dose-dependent manner. Furthermore, the expression of NLRP3, NF-κB and PKR was downregulated after curculigoside administration. Moreover, curculigoside reversed the effects of IL-1ß on MMP-9, iNOS and type II collagen expression at mRNA and protein levels in human chondrocytes in a dose-dependent manner. In conclusion, curculigoside exhibits beneficial effect on cartilage via the inhibition of NLRP3 pathway.


Assuntos
Cartilagem Articular , Osteoartrite , Humanos , Camundongos , Animais , Metaloproteinase 9 da Matriz/metabolismo , Transdução de Sinais/fisiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células Cultivadas , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Condrócitos , NF-kappa B/metabolismo , Cartilagem Articular/metabolismo , RNA Mensageiro/metabolismo , Interleucina-1beta/metabolismo
11.
Microb Cell Fact ; 22(1): 235, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968625

RESUMO

BACKGROUND: Emerging evidence has shown that extracellular vesicles (EVs) derived from gut bacteria play a crucial role in microbiota-host interactions. Here, we aimed to evaluate the attenuating effect of EVs derived from a reduced commensal bacterium, F. prausnitzii (Fp-EVs), in inflammatory bowel disease (IBD) on dextran sulfate sodium (DSS)-induced colitis in mice. RESULTS: Fp-EVs isolated by ultracentrifugation and typically exhibited a double concave disc shape with an average diameter of 172 nm. Fp-EVs treatment reduced DSS-induced weight loss, disease activity index (DAI) score, colon length shortening, histological damage, neutrophil infiltration and increased intestinal epithelial apoptotic cells in DSS-induced colitis mice. Fp-EVs upregulated the protein expression of zona occludens (ZO)-1 and Occludin and increased the ratio of Tregs in the colon tissue of colitis mice. Furthermore, Fp-EVs downregulated the expression of the proinflammatory cytokines interleukin-1ß (IL-1ß), IL-2, IL-6, IL-12a, IL-17a, Interferon-γ (IFN-γ), tumor necrosis factor - α (TNF-α), granulocyte-macrophage colony stimulating factor (GM-CSF) and upregulated the anti-inflammatory cytokines IL-4, IL-10, and transforming growth factor ß (TGF-ß) in DSS-treated mice. Moreover, Fp-EV treatment markedly reduced the phosphorylation of these proteins Nuclear factor-κB (NF-κB) and Mitogen activated protein kinase (MAPK), and regulated the expression of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase-1 (HO-1). CONCLUSION: Our findings revealed that Fp-EVs attenuated DSS-induced colitis by modulating the intestinal mucosal barrier function and immunological profile. Our findings reveal that Fp-EVs attenuate DSS-induced colitis by modulating intestinal mucosal barrier function and the immunological profile.


Assuntos
Colite , Vesículas Extracelulares , Animais , Camundongos , Colite/induzido quimicamente , Colo , Mucosa Intestinal/metabolismo , Citocinas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Vesículas Extracelulares/metabolismo , Sulfato de Dextrana/toxicidade , Sulfato de Dextrana/metabolismo , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
12.
Transl Cancer Res ; 12(10): 2545-2555, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37969397

RESUMO

Background: To overcome proton therapy limitations [low linear energy transfer (LET) radiation with a relative biological effectiveness (RBE) typically ranging from 1.1 to 1.2], radiosensitization techniques can be employed to increase the radiosensitivity of tumor cells and improve the effectiveness of radiation therapy. In this study, we suggest using a boron-based medium to overcome the biological limitations of proton therapy. By inducing the hydrogen-boron fusion reaction (p + 11B → 3α) of incident protons and capturing thermal neutrons [10B + n → 7Li3+ (0.84 MeV) + 4He2+ (1.47 MeV) + γ (0.477 MeV)], high LET α particles can be released. We propose a "ternary" radiotherapy model to enhance the biological effect of proton therapy. Methods: Using Monte Carlo simulation, the possibility of interacting low-energy proton beams with 11B and thermal neutrons with 10B to produce α particles with higher RBE to enhance the biological effect of proton radiotherapy were investigated. And the number and location of α particles and thermal neutrons produced by the interaction of protons with natural boron had also been studied. Results: Under the basic principle of the "ternary" radiotherapy model, comparative analyses of neutrons and α particles produced by proton beams of different energies incident on the phantoms, which were composed of boron isotopes of different concentrations in proportion to the phantoms, have shown that the α particle yield decreased with decreasing boron doping concentration, whereas the neutron yield increased with decreasing boron doping concentration. The distribution of thermal neutrons and α particles in the longitudinal direction of the proton beam were also studied, and it was found that the number of α particles produced was high at high boron concentrations, and the locations of α and thermal neutrons were close to the treatment target. Conclusions: The proton therapy ternary model is theoretically feasible from the perspective of mathematical analysis and Monte Carlo simulation experiments.

13.
J Appl Clin Med Phys ; 24(12): e14119, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37568269

RESUMO

BACKGROUND: Dose to heart substructures is a better predictor for major adverse cardiac events (MACE) than mean heart dose (MHD). We propose an avoidance planning strategy for important cardiac substructures. MATERIAL AND METHODS: Two plans, clinical and cardiac substructure-avoidance plan, were generated for twenty patients. Five dose-sensitive substructures, including left ventricle, pulmonary artery, left anterior descending branch, left circumflex branch and the coronary artery were chosen. The avoidance plan aims to meet the target criteria and organ-at-risk (OARs) constraints while minimizing the dose parameters of the above five substructures. The dosimetric assessments included the mean dose and the maximum dose of cardiac substructures and several volume parameters. In addition, we also evaluated the relative risk of coronary artery disease (CAD), chronic heart failure (CHF), and radiation pneumonia (RP). RESULTS: Pearson correlation coefficient and R2 value of linear regression fitting demonstrated that MHD had poor prediction ability for the mean dose of the cardiac substructures. Compared to clinical plans, an avoidance plan is able to statistically significantly decrease the dose to key substructures. Meanwhile, the dose to OARs and the coverage of the target are comparable in the two plans. In addition, it can be observed that the avoidance plan statistically decreases the relative risks of CAD, CHF, and RP. CONCLUSIONS: The substructure-avoidance planning strategy that incorporates the cardiac substructures into optimization process, can protect the important heart substructures, such as left ventricle, left anterior descending branch and pulmonary artery, achieving the substantive sparing of dose-sensitive cardiac structures, and have the potential to decrease the relative risks of CAD, CHF, and RP.


Assuntos
Cardiopatias , Pneumonite por Radiação , Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , Coração , Vasos Coronários , Cardiopatias/prevenção & controle , Planejamento da Radioterapia Assistida por Computador , Órgãos em Risco
14.
J Transl Med ; 21(1): 572, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626430

RESUMO

BACKGROUND: Immunotoxins are antibody-toxin conjugates that bind to surface antigens and exert effective cytotoxic activity after internalization into tumor cells. Immunotoxins exhibit effective cytotoxicity and have been approved by the FDA to treat multiple hematological malignancies, such as hairy cell leukemia and cutaneous T-cell lymphoma. However, most of the internalized immunotoxin is degraded in lysosomes, and only approximately 5% of free toxin escapes into the cytosol to exert cytotoxicity. Many studies have improved immunotoxins by engineering the toxin fragment to reduce immunogenicity or increase stability, but how the antibody fragment contributes to the activity of immunotoxins has not been well demonstrated. METHODS: In the current study, we used 32A9 and 42A1, two anti-GPC3 antibodies with similar antigen-binding capabilities and internalization rates, to construct scFv-mPE24 immunotoxins and evaluated their in vitro and in vivo antitumor activities. Next, the antigen-binding capacity, trafficking, intracellular protein stability and release of free toxin of 32A9 scFv-mPE24 and 42A1 scFv-mPE24 were compared to elucidate their different antitumor activities. Furthermore, we used a lysosome inhibitor to evaluate the degradation behavior of 32A9 scFv-mPE24 and 42A1 scFv-mPE24. Finally, the antigen-binding patterns of 32A9 and 42A1 were compared under neutral and acidic pH conditions. RESULTS: Although 32A9 and 42A1 had similar antigen binding capacities and internalization rates, 32A9 scFv-mPE24 had superior antitumor activity compared to 42A1 scFv-mPE24. We found that 32A9 scFv-mPE24 exhibited faster degradation and drove efficient free toxin release compared to 42A1 scFv-mPE24. These phenomena were determined by the different degradation behaviors of 32A9 scFv-mPE24 and 42A1 scFv-mPE24 in lysosomes. Moreover, 32A9 was sensitive to the low-pH environment, which made the 32A9 conjugate easily lose antigen binding and undergo degradation in lysosomes, and the free toxin was then efficiently produced to exert cytotoxicity, whereas 42A1 was resistant to the acidic environment, which kept the 42A1 conjugate relatively stable in lysosomes and delayed the release of free toxin. CONCLUSIONS: These results showed that a low pH-sensitive antibody-based immunotoxin degraded faster in lysosomes, caused effective free toxin release, and led to improved cytotoxicity compared to an immunotoxin based on a normal antibody. Our findings suggested that a low pH-sensitive antibody might have an advantage in the design of immunotoxins and other lysosomal degradation-dependent antibody conjugate drugs.


Assuntos
Neoplasias Hematológicas , Imunotoxinas , Humanos , Imunotoxinas/farmacologia , Anticorpos , Citosol , Concentração de Íons de Hidrogênio
15.
Front Psychol ; 14: 1012701, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874841

RESUMO

Introduction: Personal relationships have long been a concern in education. Most studies indicate that good personal relationships are generally positively correlated with academic performance. However, few studies have compared how different types of personal relationships correlate with academic performance, and the conclusions of existing studies are inconsistent. Based on a large sample, the current study compared how the three closest types of personal relationships among students (with parents, teachers, and their peers) compared with their academic performance. Methods: Cluster sampling was used to issue questionnaires to students in Qingdao City, Shandong Province, China in 2018 (Study 1) and in 2019 (Study 2). The actual sample size included 28168 students in Study 1 and 29869 students in Study 2 (both studies, Grades 4 and 8), thus totaling 58037 students. All students completed a personal relationship questionnaire and several academic tests. Results: The results showed that: (1) the quality of personal relationships significantly and positively correlated with academic performance; (2) Among the three types of relationships tested, the quality of student-peer relationships was the most closely associated with academic achievement. Discussion: This study gives insights into future research directions in this field and also reminds educators to pay attention to the personal relationships among their students, especially peer relationships.

16.
Antiviral Res ; 209: 105509, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36572190

RESUMO

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a threat to global public health, underscoring the urgent need for the development of preventive and therapeutic measures. The spike (S) protein of SARS-CoV-2, which mediates receptor binding and subsequent membrane fusion to promote viral entry, is a major target for current drug development and vaccine design. The S protein comprises a large N-terminal extracellular domain, a transmembrane domain, and a short cytoplasmic tail (CT) at the C-terminus. CT truncation of the S protein has been previously reported to promote the infectivity of SARS-CoV and SARS-CoV-2 pseudoviruses. However, the underlying molecular mechanism has not been precisely elucidated. In addition, the CT of various viral membrane glycoproteins play an essential role in the assembly of virions, yet the role of the S protein CT in SARS-CoV-2 infection remains unclear. In this study, through constructing a series of mutations of the CT of the S protein and analyzing their impact on the packaging of the SARS-CoV-2 pseudovirus and live SARS-CoV-2 virus, we identified V1264L1265 as a new intracellular targeting motif in the CT of the S protein, that regulates the transport and subcellular localization of the spike protein through the interactions with cytoskeleton and vesicular transport-related proteins, ARPC3, SCAMP3, and TUBB8, thereby modulating SARS-CoV-2 pseudovirus and live SARS-CoV-2 virion assembly. Either disrupting the V1264L1265 motif or reducing the expression of ARPC3, SCAMP3, and TUBB8 significantly repressed the assembly of the live SARS-CoV-2 virion, raising the possibility that the V1264L1265 motif and the host responsive pathways involved could be new drug targets for the treatment of SARS-CoV-2 infection. Our results extend the understanding of the role played by the S protein CT in the assembly of pseudoviruses and live SARS-CoV-2 virions, which will facilitate the application of pseudoviruses to the study of SARS-CoV-2 and provide potential strategies for the treatment of SARS-CoV-2 infection.


Assuntos
COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus , Sequência de Aminoácidos , Tubulina (Proteína)/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo
17.
Radiat Oncol ; 17(1): 219, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36587224

RESUMO

BACKGROUND: The study objective was to validate the relative biological effectiveness (RBE) in RayStation for carbon-ion radiotherapy (CIRT) using the Syngo treatment planning system as reference. METHODS: Local effect model I was established in RayStation (Ray-LEM) with the same parameters as in LEM I in Syngo (Syngo-LEM). Three cube plans covering most of the tumors treated at our center were generated with Syngo-LEM. Ray-LEM re-calculated the Syngo plans and compared the RBEs to the Syngo counterparts. The results showed that RayStation RBE was smaller than Syngo RBE. To ensure that Ray-LEM reproduced Syngo RBE, the observed deviations were used to scale the maximum RBE (RBEmax) in Ray-LEM. After this calibration, we further compared the RayStation RBE to Syngo RBE using additional plans in both homogeneous phantoms and patients, to ensure that the calibrated Ray-LEM reproduced Syngo RBE even with more complex planning features. RESULTS: The calibration increased the RBEmax by 2.3% to raise the Ray-LEM RBE. The target mean RBE deviations in the phantom evaluation plans were median: 0.0 (minimum: - 1.1 to maximum: 0.7) %, and the target mean RBE deviations of the clinical target volumes of 16 patient cases were - 0.4 (- 1.5 to 0.2) %. CONCLUSIONS: The residual RBE difference between RayStation and Syngo was found to be ≤ 1.0%. Thus, we can propose to use RayStation for clinical CIRT treatment planning. However, the potential differences due to the absorbed beam model warrants further exploration.


Assuntos
Radioterapia com Íons Pesados , Planejamento da Radioterapia Assistida por Computador , Humanos , Eficiência Biológica Relativa , Dosagem Radioterapêutica , Calibragem , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia com Íons Pesados/métodos , Carbono/uso terapêutico
18.
Front Immunol ; 13: 866035, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757752

RESUMO

Background: Eosinophilic granulomatosis with polyangiitis (EGPA) is characterized by asthma-like attacks in its early stage, which is easily misdiagnosed as severe asthma. Therefore, new biomarkers for the early diagnosis of EGPA are needed, especially for differentiating the diagnosis of asthma. Objectives: To identify serum biomarkers that can be used for early diagnosis of EGPA and to distinguish EGPA from severe asthma. Method: Data-independent acquisition (DIA) analysis was performed to identify 45 healthy controls (HC), severe asthma (S-A), and EGPA patients in a cohort to screen biomarkers for early diagnosis of EGPA and to differentiate asthma diagnosis. Subsequently, parallel reaction monitoring (PRM) analysis was applied to a validation cohort of 71 HC, S-A, and EGPA patients. Result: Four candidate biomarkers were identified from DIA and PRM analysis-i.e., serum amyloid A1 (SAA1), fibrinogen-α (FGA), and serum amyloid P component (SAP)-and were upregulated in the EGPA group, while cholesteryl ester transfer protein (CETP) was downregulated in the EGPA group compared with the S-A group. Receiver operating characteristics analysis shows that, as biomarkers for early diagnosis of EGPA, the combination of SAA1, FGA, and SAP has an area under the curve (AUC) of 0.947, a sensitivity of 82.35%, and a specificity of 100%. The combination of SAA1, FGA, SAP, and CETP as biomarkers for differential diagnosis of asthma had an AUC of 0.921, a sensitivity of 78.13%, and a specificity of 100%, which were all larger than single markers. Moreover, SAA1, FGA, and SAP were positively and CETP was negatively correlated with eosinophil count. Conclusion: DIA-PRM combined analysis screened and validated four previously unexplored but potentially useful biomarkers for early diagnosis of EGPA and differential diagnosis of asthma.


Assuntos
Asma , Proteínas de Transferência de Ésteres de Colesterol , Síndrome de Churg-Strauss , Fibrinogênio , Granulomatose com Poliangiite , Transtornos Leucocíticos , Proteína Amiloide A Sérica , Componente Amiloide P Sérico , Asma/sangue , Asma/diagnóstico , Biomarcadores/sangue , Estudos de Casos e Controles , Proteínas de Transferência de Ésteres de Colesterol/sangue , Diagnóstico Diferencial , Fibrinogênio/metabolismo , Granulomatose com Poliangiite/sangue , Granulomatose com Poliangiite/diagnóstico , Humanos , Proteômica , Proteína Amiloide A Sérica/metabolismo , Componente Amiloide P Sérico/metabolismo
19.
J Biomed Res ; 36(3): 155-166, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35545451

RESUMO

High-affinity antibodies are widely used in diagnostics and for the treatment of human diseases. However, most antibodies are isolated from semi-synthetic libraries by phage display and do not possess in vivo affinity maturation, which is triggered by antigen immunization. It is therefore necessary to engineer the affinity of these antibodies by way of in vitro assaying. In this study, we optimized the affinity of two human monoclonal antibodies which were isolated by phage display in a previous related study. For the 42A1 antibody, which targets the liver cancer antigen glypican-3, the variant T57H in the second complementarity-determining region of the heavy chain (CDR-H2) exhibited a 2.6-fold improvement in affinity, as well as enhanced cell-binding activity. For the I4A3 antibody to severe acute respiratory syndrome coronavirus 2, beneficial single mutations in CDR-H2 and CDR-H3 were randomly combined to select the best synergistic mutations. Among these, the mutation S53P-S98T improved binding affinity (about 3.7 fold) and the neutralizing activity (about 12 fold) compared to the parent antibody. Taken together, single mutations of key residues in antibody CDRs were enough to increase binding affinity with improved antibody functions. The mutagenic combination of key residues in different CDRs creates additive enhancements. Therefore, this study provides a safe and effective in vitro strategy for optimizing antibody affinity.

20.
J Transl Med ; 20(1): 33, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35033121

RESUMO

BACKGROUND: Compelling evidences demonstrated that gut microbiota dysbiosis plays a critical role in the pathogenesis of inflammatory bowel diseases (IBD). Therapies for targeting the microbiota may provide alternative options for the treatment of IBD, such as probiotics. Here, we aimed to investigate the protective effect of a probiotic strain, Pediococcus pentosaceus (P. pentosaceus) CECT 8330, on dextran sulfate sodium (DSS)-induced colitis in mice. METHODS: C57BL/6 mice were administered phosphate-buffered saline (PBS) or P. pentosaceus CECT 8330 (5 × 108 CFU/day) once daily by gavage for 5 days prior to or 2 days after colitis induction by DSS. Weight, fecal conditions, colon length and histopathological changes were examined. ELISA and flow cytometry were applied to determine the cytokines and regulatory T cells (Treg) ratio. Western blot was used to examine the tight junction proteins (TJP) in colonic tissues. Fecal short-chain fatty acids (SCFAs) levels and microbiota composition were analyzed by targeted metabolomics and 16S rRNA gene sequencing, respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Cluster of orthologous groups of proteins (COG) pathway analysis were used to predict the microbial functional profiles. RESULTS: P. pentosaceus CECT 8330 treatment protected DSS-induced colitis in mice as evidenced by reducing the weight loss, disease activity index (DAI) score, histological damage, and colon length shortening. P. pentosaceus CECT 8330 decreased the serum levels of proinflammatory cytokines (TNF-α, IL-1ß, and IL-6), and increased level of IL-10 in DSS treated mice. P. pentosaceus CECT 8330 upregulated the expression of ZO-1, Occludin and the ratio of Treg cells in colon tissue. P. pentosaceus CECT 8330 increased the fecal SCFAs level and relative abundances of several protective bacteria genera, including norank_f_Muribaculaceae, Lactobacillus, Bifidobacterium, and Dubosiella. Furthermore, the increased abundances of bacteria genera were positively correlated with IL-10 and SCFAs levels, and negatively associated with IL-6, IL-1ß, and TNF-α, respectively. The KEGG and COG pathway analysis revealed that P. pentosaceus CECT 8330 could partially recover the metabolic pathways altered by DSS. CONCLUSIONS: P. pentosaceus CECT 8330 administration protects the DSS-induced colitis and modulates the gut microbial composition and function, immunological profiles, and the gut barrier function. Therefore, P. pentosaceus CECT 8330 may serve as a promising probiotic to ameliorate intestinal inflammation.


Assuntos
Colite , Microbioma Gastrointestinal , Animais , Colo/patologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Imunidade , Camundongos , Camundongos Endogâmicos C57BL , Pediococcus pentosaceus/genética , RNA Ribossômico 16S/genética
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