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1.
J Clin Immunol ; 44(3): 80, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462559

RESUMO

OBJECTIVE: We sought to explore the prevalence of type I interferon-neutralizing antibodies in a Chinese cohort and its clinical implications during the Omicron variant wave of SARS-CoV-2. METHODS: Type I interferon (IFN) autoantibodies possessing neutralizing capabilities were identified using luciferase assays. The capacity of the autoantibodies for in vitro interference with antiviral activity of IFN was assessed by using a SARS-CoV-2 replicon system. An analysis of the demographic and clinical profiles of patients exhibiting neutralizing antibodies was also conducted. RESULTS: In this cohort, 11.8% of severe/critical cases exhibited the existence of type I IFN-neutralizing antibodies, specifically targeting IFN-α2, IFN-ω, or both, with an elderly male patient tendency. Notably, these antibodies exerted a pronounced inhibitory effect on the antiviral activity of IFN against SARS-CoV-2 under controlled in vitro conditions. Furthermore, a noteworthy correlation was discerned between the presence of these neutralizing antibodies and critical clinical parameters, including C-reactive protein (CRP) levels, D-dimer levels, and lymphocyte counts. CONCLUSION: The presence of type I IFN-neutralizing antibodies is a pervasive risk factor for severe/critical COVID-19 in the Chinese population.


Assuntos
COVID-19 , Interferon Tipo I , Idoso , Humanos , Masculino , Autoanticorpos , COVID-19/epidemiologia , SARS-CoV-2 , Prevalência , China/epidemiologia , Anticorpos Neutralizantes , Antivirais
2.
J Med Virol ; 96(3): e29546, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38516804

RESUMO

Tapasin, a crucial molecular chaperone involved viral antigen processing and presentation, plays an important role in antivirus immunity. However, its impact on T cell differentiation in the context of virus clearance remains unclear. In this study, we employed induced pluripotent stem cells to differentiate into hepatocyte-like cell, which were subsequently inserted to the inverted colloidal crystal scaffolds, thus establishing a hepatocyte organoid (HO). By inoculating hepatitis B virus (HBV) particles in the system, we successfully engineered a robust in vitro HBV infection model for at least 3 weeks. Furthermore, we aimed to explore the effects of lentivirus-mediated short hairpin RNA (shRNA) targeting human Tapasin on the differentiation and antiviral function of CD8+ T cells. Specifically, we transfected dendritic cells (DCs) with Tapasin-shRNA and cocultured with T cells. The results demonstrated that Tapasin-shRNA transfected DCs effectively suppressed T cell proliferation and impeded HBV-specific cytotoxic T lymphocyte responses. Our investigation also revealed the role of mTOR pathway activation in reducing autophagy activity within CD8+ T cells. Expressions of autophagy-related proteins, beclin-1, LC3II/LC3I were decreased and PI3K/AKT/mTOR activity was increased in Tapasin-shRNA group. Collectively, our findings elucidate that shRNA targeting the Tapasin gene within DCs inhibits T cell differentiation by reducing autophagy activity to hamper viral clearance in the HBV-infected HO.


Assuntos
Células Dendríticas , Hepatite B , Proteínas de Membrana Transportadoras , Humanos , Autofagia/genética , Linfócitos T CD8-Positivos/metabolismo , Células Dendríticas/metabolismo , Regulação para Baixo , Hepatite B/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B , Hepatócitos/metabolismo , Células-Tronco Pluripotentes Induzidas , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Interferente Pequeno/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Organoides/metabolismo , Organoides/virologia
3.
Plant Cell Environ ; 47(7): 2377-2395, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38516721

RESUMO

The root rot mainly caused by Fusarium solani is a bottleneck in the cultivation of Panax notoginseng. In this study, we reported a gene encoding a plant cell wall structural protein, P. notoginseng proline-rich protein (PnPRPL1), whose transcription was upregulated by F. solani and induced by some hormone signals. The PnPRPL1 recombinant protein significantly inhibited the growth and conidial germination of the root rot pathogens. Downregulation of PnPRPL1 by RNA interference (RNAi) in P. notoginseng leaves increased the susceptibility to F. solani, whereas overexpression of PnPRPL1 in tobacco (Nicotiana tabacum) enhanced the resistance to F. solani. Compared with wild-type tobacco, the PnPRPL1-overexpressing transgenic tobacco had higher reactive oxygen species (ROS)-scavenging enzyme activities, lower ROS levels, and more lignin and callose deposition. The opposite results were obtained for the P. notoginseng expressing PnPRPL1 RNAi fragments. Furthermore, the PnPRPL1 promoter transcription activity was induced by several plant hormones and multiple stress stimuli. In addition, the transcription factor PnWRKY27 activated the expression of PnPRPL1 by directly binding to the promoter region. Thus, PnPRPL1, which is positively regulated by a WRKY transcription factor, encodes an antimicrobial protein that also mediates ROS homoeostasis and callose/lignin deposition during the response to F. solani infection.


Assuntos
Parede Celular , Fusarium , Nicotiana , Panax notoginseng , Doenças das Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio , Fusarium/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Parede Celular/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Doenças das Plantas/microbiologia , Nicotiana/microbiologia , Nicotiana/genética , Nicotiana/metabolismo , Panax notoginseng/microbiologia , Panax notoginseng/metabolismo , Panax notoginseng/fisiologia , Regulação da Expressão Gênica de Plantas , Resistência à Doença , Regiões Promotoras Genéticas/genética
4.
Scand J Gastroenterol ; 59(2): 204-212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37933195

RESUMO

Acute pancreatitis-induced splanchnic vein thrombosis (APISVT) is an important sequela complication of acute pancreatitis, which may cause poor prognosis, such as severe gastrointestinal hemorrhage, bowel ischemic necrosis and liver failure. However, its mechanism remains uncertain, and there is not a general consensus on the management. In this study, we reviewed the latest academic publications in APISVT, and discussed its pathogenesis, clinical presentation, adverse outcome and treatment, especially focused on the role of anticoagulant therapy. It was indicated that anticoagulation therapy can significantly elevate thrombus recanalization and reduce the incidence of complications and mortality with no increase of bleeding. Actually, as most of these studies were retrospective analyses and prospective studies included small samples, the conclusion remains controversial. Thus, well-designed randomized controlled trials are urged to verify the effectiveness and safety of anticoagulation therapy for APISVT.


Assuntos
Pancreatite , Doenças Vasculares , Trombose Venosa , Humanos , Pancreatite/complicações , Pancreatite/terapia , Anticoagulantes/uso terapêutico , Estudos Retrospectivos , Estudos Prospectivos , Doença Aguda , Veia Porta , Trombose Venosa/etiologia , Trombose Venosa/complicações , Hemorragia Gastrointestinal/complicações , Circulação Esplâncnica
5.
Rev Med Virol ; 33(6): e2476, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37578892

RESUMO

This study aimed to clarify the beneficial effect and the clinical application value of Paxlovid in the treatment of coronavirus disease-19 (COVID-19) through a systematic review. Databases including PubMed, Cochrane Library, Chinese Clinical Trial Registry, and ClinicalTrials.gov were systematically searched for interventional or observational studies on the efficacy and safety of Paxlovid in the treatment of SARS-COV-2. The relative and absolute effect sizes for the outcomes were calculated based on the data reported in the original intervention literature. The external applicability of the evidence was analysed in terms of clinical application scenarios, patient willingness, and cost utility. One interventional and three observational studies were conducted. Four studies published in 2022, had participation sample sizes ranging 1780-109,254. Based on the randomised controlled trial data, the risk of all-cause mortality, all-cause death, and hospitalisation was significantly reduced in the Paxlovid group. Serious adverse events were reduced during the study. Based on observational studies, Paxlovid can significantly reduce the risk of death and hospitalisation in older patients with COVID-19 (moderate certainty) and improve in-hospital disease progression, composite disease progression, and viral load (low certainty). Paxlovid did not improve the outcomes of death and hospitalisation (low certainty) in patients aged <65 years. As per the economic utility analysis, the economic cost of reducing one death dramatically decreased with increasing age. Early use of Paxlovid in the older adult population with COVID-19 is beneficial. However, in the setting of limited resources, Paxlovid should be prioritised for older patients.


Assuntos
COVID-19 , Humanos , Idoso , SARS-CoV-2 , Reprodutibilidade dos Testes , Progressão da Doença
6.
J Intensive Care Med ; : 8850666241228841, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38356292

RESUMO

Background: Nirmatrelvir/Ritonavir is an orally administered anti-SARS-Cov-2 drug used in mild-to-moderate COVID-19 patients. Our retrospective cohort study aims to evaluate the efficacy and safety of Nirmatrelvir/Ritonavir in severe hospitalized patients with Omicron infection, as well as in patients at high risk for progression to critical illness in real-world settings. Methods: A total of 350 patients received Nirmatrelvir/Ritonavir while 350 matched controls did not. Patients with confirmed COVID-19 were administered Nirmatrelvir 300 mg and Ritonavir 100 mg orally twice a day for 5 days, with the medication initiated on the first day after admission. The primary endpoint of the study was a composite outcome of hospitalization or death from any cause within 28 days. Secondary endpoints included the occurrence of adverse events and the evaluation of serum levels of IL-6 and viral load. Results: We documented the mortality risk from any cause within 28 days, viral load, serum IL-6 levels, and adverse events. Nirmatrelvir/Ritonavir reduced the 28-day risk of all-cause mortality by 86% (P = .011, hazard ratio (HR) = 0.14, 95% confidence interval (CI) = 0.03, 0.64). At baseline, the serum level of IL-6 was significantly higher in the antiviral treatment group compared to the control group (P < .001), but no significant difference (P = .990) was found between the two groups at discharge. In CKD patients undergoing hemodialysis, no significant worsening of renal function was observed in the Nirmatrelvir/Ritonavir treatment group compared to the control group. Conclusion: Nirmatrelvir/Ritonavir may reduce the 28-day risk of all-cause mortality in critically ill patients with COVID-19 and in patients at high risk for critical disease progression.

7.
Acta Pharmacol Sin ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609561

RESUMO

Proteolysis targeting chimeras (PROTACs) have emerged as revolutionary anticancer therapeutics that degrade disease-causing proteins. However, the anticancer performance of PROTACs is often impaired by their insufficient bioavailability, unsatisfactory tumor specificity and ability to induce acquired drug resistance. Herein, we propose a polymer-conjugated PROTAC prodrug platform for the tumor-targeted delivery of the most prevalent von Hippel-Lindau (VHL)- and cereblon (CRBN)-based PROTACs, as well as for the precise codelivery of a degrader and conventional small-molecule drugs. The self-assembling PROTAC prodrug nanoparticles (NPs) can specifically target and be activated inside tumor cells to release the free PROTAC for precise protein degradation. The PROTAC prodrug NPs caused more efficient regression of MDA-MB-231 breast tumors in a mouse model by degrading bromodomain-containing protein 4 (BRD4) or cyclin-dependent kinase 9 (CDK9) with decreased systemic toxicity. In addition, we demonstrated that the PROTAC prodrug NPs can serve as a versatile platform for the codelivery of a PROTAC and chemotherapeutics for enhanced anticancer efficiency and combination benefits. This study paves the way for utilizing tumor-targeted protein degradation for precise anticancer therapy and the effective combination treatment of complex diseases.

8.
Nanomedicine ; 60: 102758, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38852881

RESUMO

The clinical application of tumor necrosis factor-α (TNF-α) is limited by its short half-life, subeffective concentration in the targeted area and severe systemic toxicity. In this study, the recombinant polypeptide S4-TNF-α was constructed and coupled with chitosan-modified superparamagnetic iron oxide nanoparticles (S4-TNF-α-SPIONs) to achieve pH-sensitive controlled release and active tumor targeting activity. The isoelectric point (pI) of S4-TNF-α was reconstructed to approach the pH of the tumor microenvironment. The negative-charge S4-TNF-α was adsorbed to chitosan-modified superparamagnetic iron oxide nanoparticles (CS-SPIONs) with a positive charge through electrostatic adsorption at physiological pH. The acidic tumor microenvironment endowed S4-TNF-α with a zero charge, which accelerated S4-TNF-α release from CS-SPIONs. Our studies showed that S4-TNF-α-SPIONs displayed an ideal pH-sensitive controlled release capacity and improved antitumor effects. Our study presents a novel approach to enhance the pH-sensitive controlled-release of genetically engineered drugs by adjusting their pI to match the pH of the tumor microenvironment.

9.
Vascular ; : 17085381241241108, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498983

RESUMO

BACKGROUND: The retrieval of inferior vena cava filters beyond the retrieval window poses challenges, requiring alternative techniques. OBJECTIVES: To discuss the laparoscopy-assisted retrieval approach for difficult inferior vena cava filters. RESEARCH DESIGN: Case report. SUBJECTS: A 57-year-old male with a retrievable inferior vena cava filter placed 8 months prior. MEASURES: Laparoscopy-assisted retrieval technique utilized after unsuccessful interventional attempts. RESULTS: Successful retrieval of the filter despite thickened intimal tissue involvement, with no postoperative complications. CONCLUSIONS: Laparoscopy-assisted retrieval offers a direct visual approach for challenging filter removal, proving minimally invasive, safe, and effective.

10.
J Oral Rehabil ; 51(4): 666-676, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38071492

RESUMO

BACKGROUND: Temporomandibular joint osteoarthritis (TMJOA) is characterized by articular cartilage degeneration and progressive synovitis. How to effectively inhibit TMJOA in the early stage has been a hot topic in the biomedical field. As a non-invasive physiotherapy, pulsed electromagnetic field (PEMF) treatment has shown great potential in the treatment of osteoarthritis (OA) in extremity joints. OBJECTIVE: This study aims to investigate the biological effect of PEMF intervention on TMJ cartilage degeneration and synovium inflammation at the early stage of TMJOA. METHODS: PEMF (2.0 mT, 15 Hz, 2 h/day) treatment was given to rats in which TMJOA was induced by applying the unilateral anterior crossbite (UAC). Histological and immunohistochemical staining, TUNEL assay, real-time PCR and western blotting assay were performed to detect the changes of the morphology and the expression of pro-inflammatory and degradative factors in condylar cartilage and synovium. RESULTS: Obvious condylar cartilage degeneration, characterized by decreased cartilage thickness, degraded cartilage extracellular matrix, increased expression of pro-inflammatory and degradative factors (TNF-α, IL-1ß, MMP-13, ADAMTS-5, IL-6, MMP-3, MMP-9 and COL-X) and increased chondrocytes death, was observed in UAC group, accompanied by synovium hyperplasia and up-regulation of pro-inflammatory and degradative factors in synovium. PEMF intervention reversed the decreased cartilage thickness at 3 weeks and degraded cartilage extracellular matrix at 6 weeks. Moreover, the up-regulation of pro-inflammatory, degradative and hypertrophyic factors and chondrocytes death in condylar cartilage induced by UAC were inhibited to some extent. In addition, the synovium hyperplasia and the up-regulation of pro-inflammatory and degradative factors in synovium were inhibited at 3 weeks and 6 weeks. CONCLUSIONS: Appropriate PEMF stimulation can reverse the loss of cartilage extracellular matrix, the chondrocytes death, the increased expression of pro-inflammatory and degradative factors in cartilage, the decreased cartilage thickness and synovium inflammation induced by UAC at the early stage of TMJOA to some extent. PEMF stimulation may be a promising method in clinical TMJOA treatment.


Assuntos
Osteoartrite , Sinovite , Animais , Ratos , Campos Eletromagnéticos , Hiperplasia , Sinovite/terapia , Osteoartrite/terapia , Inflamação , Articulação Temporomandibular
11.
Molecules ; 29(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38675693

RESUMO

Further assessment of ultraviolet C light-emitting diode (UVC-LED) irradiation for influencing shiitake mushrooms' (Lentinus edodes) volatile and sensory properties is needed. In this study, a comparison of UVC-LED irradiation treatment on the flavor profiles in various parts of shiitake mushrooms was conducted using gas chromatography-ion mobility spectrometry (GC-IMS) and sensory analysis. Sixty-three volatile compounds were identified in shiitake mushrooms. The fresh shiitake mushrooms were characterized by the highest values of raw mushroom odors. After UVC-LED treatment, the content of C8 alcohols decreased, especially that of 1-octen-3-ol, while the content of aldehydes increased, especially the content of nonanal and decanal. The score of fatty and green odors was enhanced. For fresh samples, the mushroom odors decreased and the mushroom-like odors weakened more sharply when treated in ethanol suspension than when treated with direct irradiation. The fruit odors were enhanced using direct UVC-LED irradiation for fresh mushroom samples and the onion flavor decreased. As for shiitake mushroom powder in ethanol suspension treated with UVC-LED, the sweaty and almond odor scores decreased and the vitamin D2 content in mushroom caps and stems reached 668.79 µg/g (dw) and 399.45 µg/g (dw), respectively. The results obtained from this study demonstrate that UVC-LED treatment produced rich-flavored, quality mushroom products.


Assuntos
Odorantes , Cogumelos Shiitake , Raios Ultravioleta , Compostos Orgânicos Voláteis , Cogumelos Shiitake/química , Compostos Orgânicos Voláteis/análise , Odorantes/análise , Espectrometria de Mobilidade Iônica/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos
12.
Anal Chem ; 95(24): 9173-9181, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37279018

RESUMO

As an important metabolic intermediate of sulfur-containing amino acids in human body, homocysteine (Hcy) is regarded as an independent risk factor for atherosclerotic cardiovascular disease. Therefore, real-time monitoring of the fluctuation of Hcy level is of great importance for the early diagnosis as well as the treatment of atherosclerosis. Herein, a new two-photon (TP) fluorescent probe (RH-2) was developed via a hydrogen bond-assisted strategy, which had a high specificity for detecting Hcy over cysteine (Cys) and glutathione (GSH) in solution, cells, and tissue. Probe RH-2 was applied to the quantitative determination of Hcy in human serum successfully. Moreover, the two-photon fluorescence (TPF) imaging of abnormal expression of Hcy in aortic vessels and liver of atherosclerotic model mice were fulfilled by RH-2. Therefore, probe RH-2 can be served as a potential tool to understand the function of Hcy in atherosclerosis, supplying a clinical promise for the early diagnosis of atherosclerosis (AS).


Assuntos
Aterosclerose , Corantes Fluorescentes , Humanos , Animais , Camundongos , Corantes Fluorescentes/química , Cisteína/metabolismo , Células HeLa , Microscopia de Fluorescência/métodos , Glutationa , Espectrometria de Fluorescência , Aterosclerose/diagnóstico por imagem , Homocisteína
13.
Small ; : e2308424, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38081800

RESUMO

The rapid, simultaneous, and accurate identification of multiple non-nucleic acid targets in clinical or food samples at room temperature is essential for public health. Argonautes (Agos) are guided, programmable, target-activated, next-generation nucleic acid endonucleases that could realize one-pot and multiplexed detection using a single enzyme, which cannot be achieved with CRISPR/Cas. However, currently reported thermophilic Ago-based multi-detection sensors are mainly employed in the detection of nucleic acids. Herein, this work proposes a Mesophilic Argonaute Report-based single millimeter Polystyrene Sphere (MARPS) multiplex detection platform for the simultaneous analysis of non-nucleic acid targets. The aptamer is utilized as the recognition element, and a single millimeter-sized polystyrene sphere (PSmm ) with a large concentration of guide DNA on the surface served as the microreactor. These are combined with precise Clostridium butyricum Ago (CbAgo) cleavage and exonuclease I (Exo I) signal amplification to achieve the efficient and sensitive recognition of non-nucleic acid targets, such as mycotoxins (<60 pg mL-1 ) and pathogenic bacteria (<102 cfu mL-1 ). The novel MARPS platform is the first to use mesophilic Agos for the multiplex detection of non-nucleic acid targets, overcoming the limitations of CRISPR/Cas in this regard and representing a major advancement in non-nucleic acid target detection using a gene-editing-based system.

14.
J Med Virol ; 95(4): e28746, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37185848

RESUMO

Hepatitis B virus (HBV) specific T cell immune response plays a vital role in viral clearance. Dendritic cell derived exosomes (Dexs) can activate T cell immunity effectively. Tapasin (TPN) is involved in antigen processing and specific immune recognition. In the present study, we elucidated that Dexs loading TPN (TPN-Dexs) could enhance CD8+ T cell immune response and inhibit virus replication in HBV transgenic mice. T cell immune response and the ability of inhibiting HBV replication were measured in HBV transgenic mice immunized with TPN-Dexs. Meanwhile, CD8+ T cell autophagy and specific T cell immune responses were measured in vitro and vivo, and the mechanisms probably involved in were explored. Purified TPN-Dexs could be taken up into the cytoplasm of DCs and upregulate CD8+ T cell autophagy to enhance specific T cell immune response. In addition, TPN-Dexs could increase the expression of AKT and decrease the expression of mTOR in CD8+ T cells. Further research confirmed that TPN-Dexs could inhibit virus replication and decrease the expression of HBsAg in the liver of HBV transgenic mice. Nevertheless, those also could elicit mice hepatocytes damage. In conclusion, TPN-Dexs could enhance specific CD8+ T cell immune responses via the AKT/mTOR pathway to regulate the autophagy and exert the antiviral effect in HBV transgenic mice.


Assuntos
Exossomos , Vírus da Hepatite B , Camundongos , Animais , Linfócitos T CD8-Positivos , Proteínas Proto-Oncogênicas c-akt , Camundongos Transgênicos , Serina-Treonina Quinases TOR , Apresentação de Antígeno , Autofagia , Camundongos Endogâmicos C57BL
15.
Cytotherapy ; 25(10): 1091-1100, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37422745

RESUMO

BACKGROUND AIMS: The γδ T-cells (GDT) are a subpopulation of lymphocytes expressing a distinct T-cell receptor coded by the TRG and TRD genes. GDTs may have immunoregulatory function after stem cell transplantation (SCT), but the relationship between GDT clonality and acute graft-versus-host disease (aGVHD) is not known. METHODS: We prospectively studied spectratype complex complexity of TCR Vγ (γ) and TCR Vδ (δ) pre-SCT and at approximately day 100 and day 180 post-SCT in a cohort of immunocompetent children receiving allogeneic umbilical cord blood SCT for nonmalignant diseases, with identical reduced-intensity conditioning and aGVHD prophylaxis. RESULTS: We studied 13 children undergoing SCT at a median age of 0.9 years (total range 0.4-16.6). In those with grade 0-1 aGVHD (N = 10), the spectratype complexity of most γ and δ genes was not significantly different from baseline at day 100 or day 180 post-SCT, and there was balanced expression of genes at the γ and δ loci. In those with grade 3 aGVHD (N = 3), spectratype complexity was significantly below baseline at day 100 and day 180, and there was relative overexpression of δ2. CD3+ cell counts were also lower in participants with grade 3 aGVHD. CONCLUSIONS: Recovery of a polyclonal GDT repertoire is an early part of immunological recovery after SCT. γ and δ gene expression is balanced in young children before and after SCT. Severe aGVHD is associated with GDT oligoclonality post-SCT and with skewed expression of δ2, which has not been previously reported. This association may reflect aGVHD therapy or aGVHD-associated immune dysregulation. Further studies of GDT clonality during the early post-SCT period may establish whether abnormal GDT spectratype precedes the clinical manifestations of aGVHD.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Criança , Pré-Escolar , Lactente , Adolescente , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Transplante Homólogo , Doença Enxerto-Hospedeiro/genética , Receptores de Antígenos de Linfócitos T , Doença Aguda
16.
BMC Cancer ; 23(1): 54, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36647053

RESUMO

BACKGROUND: Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are of potential magnetic resonance imaging (MRI) contrast agents for tumor diagnosis. However, ultrasmall particle size or negative surface charge lead to relative short half-life which limit the utilization of USPIO for in vivo MRI contrast agents. METHODS: Superparamagnetic Fe3O4 nanoparticles coated with polyacrylic acid (PAA)were synthetized, and modified by 3-amino propanol and 3-diethyl amino propyl amine. The characteristics of superparamagnetic Fe3O4 nanoparticles were investigated through transmission electron microscopy, X-ray diffraction analysis, Zata potential analysis, thermogravimetric analysis, and relaxation properties analysis. Magnetic resonance imaging animal experiment was performed. RESULTS: The synthetized nanoparticles were irregular spherical, with small particle size, few agglomeration, and good dispersion in water. After modification, the potential fluctuation of nanoparticles was small, and the isoelectric point of nanoparticles changed to high pH. After 3-amino propanol modification, the weight loss of the curve from 820 to 940 °C was attributed to the decomposition of 3-amino propanol molecules on the surface. The T1 relaxation rate of nanoparticles changed little before and after modification, which proved that the modification didn't change the relaxation time. Brighter vascular images were observed after 3-amino propanol modification through measurement of magnetic resonance tumor imaging. CONCLUSION: These data indicated the Fe3O4 nanoparticles modified by 3-amino propanol should be a better contrast agent in the field of magnetic resonance tumor imaging.


Assuntos
Nanopartículas de Magnetita , Neoplasias , Animais , Meios de Contraste , 1-Propanol , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Nanopartículas de Magnetita/química , Propanóis
17.
Inorg Chem ; 62(48): 19498-19506, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37987809

RESUMO

Ribonucleotide reductase (RNR) catalyzes the reduction of ribonucleotides to deoxyribonucleotides in all organisms. There is an ∼35 Å long-range electron-hole transfer pathway during the catalytic process of class Ia RNR, which can be described as Tyr122ß â†” [Trp48ß]? ↔ Tyr356ß â†” Tyr731α ↔ Tyr730α ↔ Cys439α. The formation of the Y122• radical initiates this long-range radical transfer process. However, the generation mechanism of Y122• is not yet clear due to confusion over the intermediate X structures. Based on the two reported X structures, we examined the possible mechanisms of Y122• generation by density functional theory (DFT) calculations. Our examinations revealed that the generation of the Y122• radical from the two different core structures of X was via a similar two-step reaction, with the first step of proton transfer for the formation of the proton receptor of Y122 and the second step of a proton-coupled long-range electron transfer reaction with the proton transfer from the Y122 hydroxyl group to the terminal hydroxide ligand of Fe1III and simultaneously electron transfer from the side chain of Y122 to Fe2IV. These findings provide an insight into the formation mechanism of Y122• catalyzed by the double-iron center of the ß subunit of class Ia RNR.


Assuntos
Ribonucleotídeo Redutases , Ribonucleotídeo Redutases/metabolismo , Prótons , Transporte de Elétrons , Ferro/química , Catálise , Tirosina/química
18.
BMC Infect Dis ; 23(1): 440, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386364

RESUMO

BACKGROUND: Hydrogen/oxygen therapy contribute to ameliorate dyspnea and disease progression in patients with respiratory diseases. Therefore, we hypothesized that hydrogen/oxygen therapy for ordinary coronavirus disease 2019 (COVID-19) patients might reduce the length of hospitalization and increase hospital discharge rates. METHODS: This retrospective, propensity-score matched (PSM) case-control study included 180 patients hospitalized with COVID-19 from 3 centers. After assigned in 1:2 ratios by PSM, 33 patients received hydrogen/oxygen therapy and 55 patients received oxygen therapy included in this study. Primary endpoint was the length of hospitalization. Secondary endpoints were hospital discharge rates and oxygen saturation (SpO2). Vital signs and respiratory symptoms were also observed. RESULTS: Findings confirmed a significantly lower median length of hospitalization (HR = 1.91; 95% CIs, 1.25-2.92; p < 0.05) in the hydrogen/oxygen group (12 days; 95% CI, 9-15) versus the oxygen group (13 days; 95% CI, 11-20). The higher hospital discharge rates were observed in the hydrogen/oxygen group at 21 days (93.9% vs. 74.5%; p < 0.05) and 28 days (97.0% vs. 85.5%; p < 0.05) compared with the oxygen group, except for 14 days (69.7% vs. 56.4%). After 5-day therapy, patients in hydrogen/oxygen group exhibited a higher level of SpO2 compared with that in the oxygen group (98.5%±0.56% vs. 97.8%±1.0%; p < 0.001). In subgroup analysis of patients received hydrogen/oxygen, patients aged < 55 years (p = 0.028) and without comorbidities (p = 0.002) exhibited a shorter hospitalization (median 10 days). CONCLUSION: This study indicated that hydrogen/oxygen might be a useful therapeutic medical gas to enhance SpO2 and shorten length of hospitalization in patients with ordinary COVID-19. Younger patients or those without comorbidities are likely to benefit more from hydrogen/oxygen therapy.


Assuntos
COVID-19 , Humanos , Estudos de Casos e Controles , Estudos Retrospectivos , COVID-19/terapia , Oxigênio/uso terapêutico , Hidrogênio/uso terapêutico
19.
J Oral Pathol Med ; 52(1): 47-55, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36367442

RESUMO

BACKGROUND: 34-kDa translocase of the outer mitochondrial membrane (TOMM34) has been reported highly expressed in many cancers and is positively correlated to poorer prognosis. Our prior study showed TOMM34 is highly expressed in oral squamous cell carcinoma (OSCC) and is closely related to TNM classification and tumor size. TOMM34 is also associated with lymph node metastasis and poorer overall survival and disease-free survival in HPV-negative OSCC. METHODS: We knocked down TOMM34 in OSCC cells (SCC15, HPV positive; Cal27, HPV negative) with siRNA and over-expressed with plasmids. The effects of TOMM34 on cell proliferation, migration and invasion abilities were detected by EdU assay, CCK-8 assay, wound-healing assay, and Transwell assay. We also detected the mitochondrial morphology and the intracellular Reactive Oxygen Species (ROS) level by fluorescence staining and flow cytometry. Finally, we monitored the protein levels of ERK pathway-related molecules. RESULTS: TOMM34 knockdown decreased the proliferation in SCC15 and Cal27, and weakened the migration and invasion abilities as well. Mitochondria became shorter, in the shape of dots or short rods, suggesting that mitochondrial damage occurred. Intracellular ROS levels increased significantly after knockdown TOMM34 and decreased after over-expressing TOMM34. The phosphorylation levels of ERK1/2 and MEK1/2 in SCC15 were significantly higher than in Cal27. Besides, the phosphorylation levels of ERK1/2 and MEK1/2 were inhibited in SCC15 after knockdown of TOMM34, but not in Cal27. CONCLUSION: TOMM34 promotes the cell proliferation, migration, and invasion of OSCC. In addition, TOMM34 participates in maintaining the mitochondrial shape and reducing the intracellular ROS level to protect cancer cells. Furthermore, TOMM34 increases the activity of ERK1/2 and MEK1/2 in HPV-positive OSCC cells but not in HPV-negative.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias Bucais/patologia , Espécies Reativas de Oxigênio , Proliferação de Células , Mitocôndrias/patologia , Linhagem Celular Tumoral , Movimento Celular , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial
20.
Phys Chem Chem Phys ; 25(28): 18889-18902, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37403626

RESUMO

Iron and nitrogen codoped carbon (Fe-N-C) materials are promising alternatives to precious metal catalysts for the carbon dioxide electrochemical reduction reaction (CO2RR); however, the influence of the oxidation state, spin state, N-type and local environment of Fe-N on its catalytic activity remains poorly understood. In this study, we employed density functional theory (DFT) calculations to evaluate the catalytic activity of the pyridine-type FeIII/IIN4 motifs at the armchair and zigzag edges, the activity of the pyrrole-type FeIII/IIN4 sites in the bulk plane of carbon-based materials for the two-electron CO2RR by analyzing the stability of initial reactants, free-energy evolutions and energy barriers for the possible elementary reactions in the different spin states. The Fe ions in the armchair-edge pyridine-type FeN4 are mainly in the +2 oxidation state, and use the high spin state in the spin uncoupling manner to achieve the most efficient CO2-COOH-CO conversion. In contrast, the zigzag-edge pyridine-type FeIIN4 employs the medium spin state in the spin uncoupling manner to achieve the highest catalytic activity in the two-electron CO2RR. However, the Fe ions in the pyrrole-type bulk-hosted FeN4 mainly remain in the +3 valence state during the conversion process of CO2 to CO and utilize the medium spin state with spin coupling to obtain the highest catalytic activity. The corresponding kinetic analyses show that the armchair-edge pyridine-type FeIIN4 catalyst exhibited the best catalytic performance among the three cases. Consequently, these findings present significant insights into the design of Fe single-atom catalysts for enhancing CO2RR catalytic activity by producing more armchair-edge pyridine-type FeN4 sites, which may be constructed by introducing micropores in the carbon materials.

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