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OBJECTIVE: Hepatitis B virus (HBV) infection causes substantial harm to mitochondrial activity, which hinders the development of effective treatments for chronic hepatitis B (CHB). The discovery of the mitochondrial-derived short peptide MOTS-c, which possesses multiple bioactivities, offers a promising new approach in treating HBV infection. This study aims to explore the diagnostic and therapeutic potential of MOTS-c in HBV-related diseases and its molecular mechanism. DESIGN: In total, 85 healthy subjects and 404 patients with HBV infection, including 20 clinical treatment cohorts, were recruited for this study. MOTS-c levels were measured by ELISA and its diagnostic value was evaluated by receiving operating characteristic curve analysis. The therapeutic effect of MOTS-c was observed in multiple HBV-infected mice and cells through various techniques, including transcriptomic sequencing, flow cytometry, immunofluorescence and electron microscopy. Additionally, MOTS-c's potential interaction with myosin-9 (MYH9) and actin was predicted using immunoprecipitation, proteomics and target prediction software. RESULTS: MOTS-c negatively correlates with HBV DNA expression (R=-0.71), and its AUC (the area under the curve) for distinguishing CHB from healthy controls is 0.9530, and IA (immune reactive) from IC (inactive HBV carrier) is 0.8689. Inhibition of HBV replication (with a 50-70% inhibition rate) was observed alongside improved liver function without notable toxicity in vitro or in vivo. MOTS-c was found to promote mitochondrial biogenesis and enhance the MAVS (mitochondrial antiviral signalling protein) signalling pathway. The impact is dependent on MOTS-c's ability to regulate MYH9-actin-mediated mitochondrial homeostasis. CONCLUSION: MOTS-c has the potential to serve as a biomarker for the progression of HBV infection while also enhancing antiviral efficacy. These findings present a promising innovative approach for effectively treating patients with CHB. Furthermore, our research uncovers a novel role for MOTS-c in regulating MYH9-actin-mediated mitochondrial dynamics and contributing to mitochondrial biogenesis.
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Hepatite B Crônica , Hepatite B , Humanos , Camundongos , Animais , Vírus da Hepatite B , Actinas , Fatores de Transcrição , Antivirais/farmacologia , Antivirais/uso terapêuticoRESUMO
Intervertebral disk degeneration is a common disease with an unknown etiology. Currently, tissue engineering is considered to be an important method for intervertebral disk repair. Although transplanted stem cells may disrupt the repair process because of apoptosis caused by the oxidative microenvironment. Herein, bone marrow mesenchymal stem cell (BMSC) and Neochlorogenic acid (Ncg) were encapsulated into a GelMA hydrogel as a carrier to protect transplanted stem cells. Ncg effectively inhibited the oxidative stress process and reduced the apoptosis rate. A 5% GelMA hydrogel had a large pore size and porosity that provided an enhanced survival space for cells. An in vivo assessment showed that treatment with GelMA + BMSC + Ncg produced greater repair of degenerated intervertebral disks than that found in other model groups. Thus, this study may help contribute to improving stem cell transplantation for treating intervertebral disk degeneration.
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Ácido Clorogênico/análogos & derivados , Degeneração do Disco Intervertebral , Disco Intervertebral , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Ácido Quínico/análogos & derivados , Humanos , Degeneração do Disco Intervertebral/terapia , Hidrogéis/farmacologia , Transplante de Células-Tronco Mesenquimais/métodos , Células da Medula ÓsseaRESUMO
BACKGROUND: PM2.5, a known public health risk, is increasingly linked to intestinal disorders, however, the mechanisms of its impact are not fully understood. PURPOSE: This study aimed to explore the impact of chronic PM2.5 exposure on intestinal barrier integrity and to uncover the underlying molecular mechanisms. METHODS: C57BL/6 J mice were exposed to either concentrated ambient PM2.5 (CPM) or filtered air (FA) for six months to simulate urban pollution conditions. We evaluated intestinal barrier damage, microbial shifts, and metabolic changes through histopathology, metagenomics, and metabolomics. Analysis of the TLR signaling pathway was also conducted. RESULTS: The mean concentration of PM2.5 in the CPM exposure chamber was consistently measured at 70.9 ± 26.8 µg/m³ throughout the study period. Our findings show that chronic CPM exposure significantly compromises intestinal barrier integrity, as indicated by reduced expression of the key tight junction proteins Occludin and Tjp1/Zo-1. Metagenomic sequencing revealed significant shifts in the microbial landscape, identifying 35 differentially abundant species. Notably, there was an increase in pro-inflammatory nongastric Helicobacter species and a decrease in beneficial bacteria, such as Lactobacillus intestinalis, Lactobacillus sp. ASF360, and Eubacterium rectale. Metabolomic analysis further identified 26 significantly altered metabolites commonly associated with intestinal diseases. A strong correlation between altered bacterial species and metabolites was also observed. For example, 4 Helicobacter species all showed positive correlations with 13 metabolites, including Lactate, Bile acids, Pyruvate and Glutamate. Additionally, increased expression levels of TLR2, TLR5, Myd88, and NLRP3 proteins were noted, and their expression patterns showed a strong correlation, suggesting a possible involvement of the TLR2/5-MyD88-NLRP3 signaling pathway. CONCLUSIONS: Chronic CPM exposure induces intestinal barrier dysfunction, microbial dysbiosis, metabolic imbalance, and activation of the TLR2/5-MyD88-NLRP3 inflammasome. These findings highlight the urgent need for intervention strategies to mitigate the detrimental effects of air pollution on intestinal health and identify potential therapeutic targets.
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Disbiose , Inflamassomos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide , Proteína 3 que Contém Domínio de Pirina da Família NLR , Material Particulado , Receptor 2 Toll-Like , Receptor 5 Toll-Like , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Disbiose/induzido quimicamente , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Material Particulado/toxicidade , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Receptor 2 Toll-Like/metabolismo , Camundongos , Receptor 5 Toll-Like/metabolismo , Poluentes Atmosféricos/toxicidade , Masculino , Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Intestinos/microbiologiaRESUMO
OBJECTIVE: We verified a magnetic bead-based, simple, and fast method for circulating cell-free DNA (cfDNA) extraction from whole blood samples(CEWB) and characterised its utility in non-invasive prenatal testing (NIPT). METHOD: We extracted cfDNA from both plasma and whole blood of the patients using CEWB and compared it to that extracted using a Qiagen extraction kit; droplet digital polymerase chain reaction test was used to calculate the fragment size bias. In all, 304 samples were used for NIPT. RESULTS: The CEWB group (mean ± standard deviation [SD]: 4.34 ± 0.41 ng/ml plasma) reported less DNA weight yield than the Qiagen group (4.90 ± 0.50 ng/ml plasma). There was no significant difference between the CEWB group and the Qiagen group in the gene fragments (136 bp: p = 0.064 and 420 bp: p = 0.534). In a parallel cohort study to characterise the utility of the CEWB method in NIPT, the treatment group extracted by CEWB showed a sensitivity of 100%, a specificity of 99.65%, and a positive predictive value of 95%. CONCLUSIONS: This study demonstrated that CEWB achieves an acceptable yield of DNA without contamination from genomic DNA. Subsequent clinical experiments in a parallel cohort indicated its utility for NIPT.
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Ácidos Nucleicos Livres , Diagnóstico Pré-Natal , Ácidos Nucleicos Livres/análise , Estudos de Coortes , DNA , Feminino , Humanos , Reação em Cadeia da Polimerase/métodos , Gravidez , Diagnóstico Pré-Natal/métodosRESUMO
BACKGROUND: The purpose of this study was to explore the core and driving symptoms of posttraumatic stress disorder (PTSD) of firefighters before and after rescue. Identifying core symptoms of PTSD can help clinicians to understand what may be relevant targets for treatment. METHODS: The study recruited 334 firefighters in a firefighter military school in September 2017 (T1). They were followed up 3 months later (T2), during which time they participated in real rescue activities. The network structure of DSM-5 PTSD was using regularized partial correlation models and a Bayesian approach computing directed acyclic graphs. RESULTS: The most central symptom both in T1 and T2 was negative emotional state. Irritable or anger emerged as a key driver of other symptoms in traumatized firefighters. CONCLUSIONS: Negative emotional state and irritable or anger might represent important symptoms within PTSD symptomatology and may offer key targets in PTSD treatment for firefighters.
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Bombeiros , Transtornos de Estresse Pós-Traumáticos , Teorema de Bayes , China , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Estresse Pós-Traumáticos/terapiaRESUMO
Cellular senescence contributes to tumor regression through both cell autonomous and non-autonomous mechanisms. Drugs inducing cancer cell senescence and modulating senescence-associated secretory phenotype (SASP) render advantage to the cancer treatment. Breast cancer remains the second most cause of female cancer mortality, among which triple-negative breast cancer (TNBC) has a more aggressive clinical course. Our study showed that in TNBC cell lines including MDA-MB-231 and 4T1 cells, moderate concentrations of wogonin (5, 7-dihydroxy-8-methoxy-2-phenyl-4h-1-benzopyran-4-one) (50-100 µM) not only induced permanent proliferation inhibition, but also increased P16 expression, ß-galactosidase activity, senescence-associated heterochromatin foci and SASP, which are the typical characteristics of cellular senescence. Moreover, results showed that wogonin-induced senescence was partially attributed to the reactive oxygen species (ROS) accumulation upon wogonin treatment in MDA-MB-231 cells, since elimination of ROS by N-acetylcysteine (NAC) was able to repress wogonin-induced ß-galactosidase activity. Mechanistically, wogonin reduced the expression of TXNRD2, an important antioxidant enzyme in controlling the levels of cellular ROS, by altering the histone acetylation at its regulatory region. In addition, senescent MDA-MB-231 cells induced by wogonin exhibited activated NF-κB and suppressed STAT3, which were recognized as regulators of SASP. SASP from these senescent cells suppressed tumor cell growth, promoted macrophage M1 polarization in vitro and increased immune cell infiltration in xenografted tumors in vivo. These results reveal another mechanism for the anti-breast cancer activity of wogonin by inducing cellular senescence, which suppresses tumor progression both autonomously and non-autonomously.
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Neoplasias da Mama/tratamento farmacológico , Senescência Celular/efeitos dos fármacos , Flavanonas/farmacologia , Tiorredoxina Redutase 2/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , NF-kappa B/metabolismo , Transplante de Neoplasias , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de SinaisRESUMO
BACKGROUND Anterior cervical corpectomy and fusion (ACCF), together with anterior cervical discectomy and fusion (ACDF) are both effective clinical treatments for cervical spondylotic myelopathy (CSM). Cervical sagittal balance is critical to preserving normal alignment, and is also associated with clinical outcomes. MATERIAL AND METHODS We retrospectively reviewed patients who had suffered from CSM and had undergone 1-level ACCF or 2-level ACDF surgery between December 2016 and November 2017. Forty-eight patients were identified: 25 in the ACDF group and 23 in the ACCF group. All patients received follow-up for more than 12 months. The demographic data, radiographic parameters, and clinical efficacy were compared between and within groups, both pre- and postoperatively. RESULTS Both groups acquired good clinical efficacy; both Japanese Orthopedic Association (JOA) scores and Neck Disability Index (NDI) scores improved significantly. At the final follow-up visit, patients in the ACCF and ACDF groups did not differ significantly in C2-C7 Sagittal Vertebral Axis (cSVA), T1 Pelvic Angle (TPA), Neck Tilt (NT), Thoracic Inlet Angle (TIA), JOA, or NDI scores. However, the ACDF group had a significantly larger Cobb angle and T1 Slope (T1S) than the ACCF group. The postoperative Cobb angle increased significantly only in the ACDF group, while postoperative T1S significantly increased in both ACCF and ACDF groups. CONCLUSIONS Anterior cervical surgery may change the sagittal balance in terms of T1S or Cobb angle. No significant difference was found between ACCF and ACDF in clinical outcomes or representative global sagittal parameters. ACDF achieved more lordosis improvement than ACCF, with higher T1S. Surgeons need to pay extra attention to cervical sagittal balance, rather than focusing solely on decompression.
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Vértebras Cervicais/cirurgia , Discotomia/métodos , Doenças da Medula Espinal/cirurgia , Fusão Vertebral/métodos , Espondilose/cirurgia , Idoso , Vértebras Cervicais/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Estudos Retrospectivos , Doenças da Medula Espinal/patologia , Doenças da Medula Espinal/psicologia , Doenças da Medula Espinal/reabilitação , Espondilose/patologia , Espondilose/psicologia , Espondilose/reabilitação , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: Macrophages play vital roles in chronic liver injury, and have been tested as a tool for cytotherapy in liver fibrosis. However, macrophages possess ontogenic and functional heterogeneities. Some subsets are pro-fibrotic, whereas others are anti-fibrotic. This study aimed to clarify which macrophage subset is efficient for cytotherapy in liver fibrosis and to elucidate the underlying mechanisms. METHODS: Liver fibrosis was induced in mice by carbon tetrachloride injection or bile duct ligation. Bone-marrow-derived macrophages (BMDMs) were polarized into M0, M1, or M2 macrophages, respectively. BMDMs were infused into mice through the tail vein at different stages of fibrogenesis. Fibrosis progression, hepatic cell populations, and related molecular changes were evaluated. RESULTS: Both M0 and M1 BMDMs significantly ameliorated liver fibrosis, but M1 exhibited stronger therapeutic effects than M0. M2 macrophages were not effective on liver fibrosis. M1 macrophages reduced the number and activation of hepatic stellate cells (HSCs), which could be attributed at least partly to increased HSC apoptosis. M1 macrophages enhanced the recruitment of endogenous macrophages into fibrotic liver, which displayed the phenotype of Ly6Clo restorative macrophages and produced matrix metalloproteinases (MMPs) and hepatic growth factor (HGF) to enhance collagen degradation and hepatocyte proliferation, respectively. M1 macrophages also increased the number of total and activated natural killer (NK) cells in the fibrotic liver, which released TNF-related apoptosis-inducing ligand (TRAIL), inducing HSC apoptosis. CONCLUSIONS: M1 macrophages, which modulate the immune microenvironment to recruit and modify the activation of endogenous macrophages and NK cells, are effective for cytotherapy in experimental liver fibrosis. Lay summary: M1 Bone marrow-derived macrophages (BMDMs) exhibit a stronger therapeutic effect by modulating the hepatic microenvironment to recruit and modify the activation of endogenous macrophages and natural killer (NK) cells, which likely lead to hepatic stellate cells (HSCs) apoptosis and hampered fibrogenesis.
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Terapia Baseada em Transplante de Células e Tecidos/métodos , Cirrose Hepática/terapia , Macrófagos/imunologia , Animais , Antígenos Ly/metabolismo , Apoptose , Tetracloreto de Carbono/toxicidade , Microambiente Celular/imunologia , Modelos Animais de Doenças , Células Estreladas do Fígado/patologia , Células Matadoras Naturais/imunologia , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Ativação de Macrófagos , Macrófagos/classificação , Macrófagos/transplante , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos TransgênicosRESUMO
BACKGROUND & AIMS: Functional cure is achieved by a limited number of patients with chronic hepatitis B (CHB) after nucleotide analogue(s) and interferon treatment. It is urgent to develop therapies that can help a larger proportion of patients achieve functional cure. The present study was designed to explore the anti-hepatitis B virus (HBV) potency of interleukin-6 family cytokines and to characterize the underlying mechanisms of the cytokine displaying the highest anti-HBV potency. METHODS: HBV-infected cells were used to screened the anti-HBV potency of interleukin-6 family cytokines. The concentration of oncostatin M (OSM) in patients with chronic HBV infection was examined by enzyme-linked immunosorbent assay. The underlying mechanism of OSM anti-HBV was explored through RNA-seq. C57BL/6 mice injected with rAAV8-1.3HBV were used to explore the suppression effect of OSM on HBV in vivo. RESULTS: OSM is the most effective of the interleukin-6 family cytokines for suppression of HBV replication (percentage of average inhibition: hepatitis B surface antigen, 34.44%; hepatitis B e antigen, 32.52%; HBV DNA, 61.57%). Hepatitis B e antigen-positive CHB patients with high OSM levels had lower hepatitis B surface antigen and hepatitis B e antigen than those with low levels. OSM activated JAK-STAT signaling pathway promoting the formation of STAT1-IRF9 transcription factor complex. Following this, OSM increased the expression of various genes with known functions in innate and adaptive immunity, which was higher expression in patients with CHB in immune clearance phase than in immune tolerance phase (data from GEO: GSE65359). Interferon-induced transmembrane protein 1, one of the most differentially expressed genes, was identified as an HBV restriction factor involved in OSM-mediated anti-HBV effect. In vivo, we also found OSM significantly inhibited HBV replication and induced expression of antiviral effector interferon-induced transmembrane protein 1. CONCLUSIONS: Our study shows that OSM remodels the immune response against HBV and exerts potent anti-HBV activity, supporting its further development as a potential therapy for treating CHB.
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Vírus da Hepatite B , Hepatite B , Camundongos , Animais , Humanos , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B , Oncostatina M/farmacologia , Antígenos E da Hepatite B , Interleucina-6 , Camundongos Endogâmicos C57BL , Transdução de Sinais , Hepatite B/tratamento farmacológico , Interferons , Replicação ViralRESUMO
Objective: We aimed to investigate the association and diagnostic value of monocyte distribution width (MDW) for chronic hepatitis B (CHB), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). Methods: MDW levels were measured in 483 individuals (103 CHB, 77 LC, 153 HCC, and 150 controls). MDW was detected using UniCel Dx900 for specific cell volume parameters and the distribution of cell volumes. Results: Our findings revealed a dynamic upward change in MDW levels across different stages of chronic liver disease, from CHB to LC and HCC. In CHB, MDW levels were highest among HBeAg-positive CHB patients and exhibited a negative correlation with HBV markers while positively correlating with ALT levels. In LC, MDW showed a positive association with the pathological progression of LC, demonstrating consistency with CP scores. MDW proved to be equally effective as traditional detection for diagnosing LC. In HCC, MDW was positively correlated with HCC occurrence and development, with higher levels observed in the high MDW group, which also exhibited elevated AFP levels, MELD scores, and 90-day mortality rates. MDW surpassed predictive models in its effectiveness for diagnosing HCC, as well as CHB and LC, with respective areas under the curve of 0.882, 0.978, and 0.973. Furthermore, MDW emerged as an independent predictor of HCC. Conclusion: MDW holds significant diagnostic efficacy in identifying CHB, LC, and HCC. These findings suggest that MDW could serve as a promising biomarker for predicting the severity of liver diseases and aid in rational clinical treatment strategies.
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Carcinoma Hepatocelular , Hepatite B Crônica , Cirrose Hepática , Neoplasias Hepáticas , Monócitos , Humanos , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/sangue , Masculino , Feminino , Cirrose Hepática/diagnóstico , Cirrose Hepática/sangue , Pessoa de Meia-Idade , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/complicações , Adulto , Monócitos/imunologia , Diagnóstico Diferencial , Biomarcadores , Idoso , Curva ROC , Biomarcadores Tumorais/sangueRESUMO
BACKGROUND: Lumbar spondylolysis is a bone defect in the pars interarticularis of the lumbar vertebral, which is a common cause of low back pain in youth. Although non-surgical treatment is a mainstream option, surgery is necessary for patients with persistent symptoms. Buck technique is widely used as a classical direct repair technique, but it cannot achieve reduction of low-grade spondylolisthesis and reconstruction of lumbosacral sagittal balance. We have described a novel surgical procedure based on Buck technique with temporary intersegmental pedicle screw fixation, and report a series of clinical outcomes in 5 patients to provide a reference for the clinical treatment of young lumbar spondylolysis. METHODS: Five young patients with symptomatic lumbar spondylolysis with a mean age of 19.20 ± 5.41 years underwent surgical treatment after an average of 7.60 ± 1.52 months of failure to respond to conservative treatment, using a new surgical procedure based on Buck technique combined with temporary intersegmental pedicle screw fixation. RESULTS: Five patients were successfully operated without serious complications such as nerve and vascular injury. The average operation time was 109.00 ± 7.42 min, the interpretative average blood loss was 148.00 ± 31.14 ml, and the average fusion time was 11.20 ± 1.64 months. All patients were followed up for 2 years after surgery, and the visual analogue score (VAS) of low back pain and Oswestry disability index (ODI) scores were significantly improved compared with those before surgery, and the Henderson's evaluation were rated excellent or good. After the removal of the internal fixation, it was observed that temporary intersegmental fixation could repair the isthmus, reduce lumbar spondylolisthesis, and reconstruct the sagittal balance of the lumbosacral vertebrae while preserving lumbar motion and preventing intervertebral disc degeneration. Postoperative MRI indicated the Pfirrmann classification of the affected discs: 1 case from grade III to grade II, 3 cases from grade II to grade I, and 1 case remained grade II. CONCLUSIONS: Buck technique supplemented by temporary intersegmental pedicle screw fixation is a highly applicable and effective method for the treatment of adolescent lumbar spondylolysis. The isthmic fusion is accurate, and temporary intersegmental fixation can effectively prevent disc degeneration and reconstruct the sagittal balance of lumbosacral vertebra.
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Vértebras Lombares , Parafusos Pediculares , Espondilólise , Humanos , Espondilólise/cirurgia , Espondilólise/diagnóstico por imagem , Vértebras Lombares/cirurgia , Vértebras Lombares/diagnóstico por imagem , Adolescente , Masculino , Feminino , Adulto Jovem , Adulto , Resultado do Tratamento , Fusão Vertebral/métodos , Fusão Vertebral/instrumentação , Seguimentos , Dor Lombar/cirurgia , Dor Lombar/etiologiaRESUMO
Purpose: Peer information is now commonly used in solicitation. However, scholars have long focused on testing its effectiveness on increasing the donation amount without paying attention to its potential negative effects on donors. Thus, the current study employs high vs low peer donation amount (HPDA vs LPDA) information to explore its effect on "how-much-to-donate" decisions and the corresponding neural and psychological reactions at the same time. Participants and Methods: Student samples from a Chinese university and behavioral experiments with the event-related potential (ERP) method were used in this study. Results: The behavioral results are consistent with previous research in which HPDA was positively associated with higher donation levels. ERP results show the mechanisms behind decision-making can be summarized into a cognitive approach represented by cost-benefit analysis and an affective approach represented by reward perception. More surprisingly, in contrast to the behavioral results, LPDA elicits higher level of reward perception than HPDA. Conclusion: The results indicate that although HPDA leads to higher levels of donation, donors do not show higher levels of reward anticipation at the neurological level, indicating the increment of donation may come at the cost of donors. Theoretical and practical implications are also discussed.
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The hardened cement paste powder (HCP) powder, devoid of the hydration cementing property, can be regenerated and cemented into a test block with practical strength of almost 60 MPa via CO2 carbonization using appropriate means. This study established a kinetic model of CO2 curing of an HCP powder test block based on the degree of carbonization to study the carbonization reaction kinetic characteristics of the test block. The model was modified according to the characteristics of the evident temperature differences in the reaction kettle in the early, middle, and late stages of the carbonization process. The proposed model can be used to formulate and control the carbonization and cementation processes of HCP powder and can also be applied to describe the kinetics of the reaction processes of other similar systems.
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Density functional theory (DFT) is a powerful quantum mechanical computational tool to perform electronic structure calculations for materials. Few DFT methods can ensure accuracy and efficiency simultaneously. DFT + U + V is an alternative effective approach to overcome this drawback. However, the accuracy sensitively depends on the self-consistent estimation of the high-dimensional onsite and intersite Hubbard interaction U and V terms. We propose Bayesian optimization using a dropout (BOD) algorithm, one type of active learning method, to optimize U and V terms. The DFT + U + V with U/V obtained by BOD can produce improved electronic properties for diverse bulk materials of comparable quality to the hybrid functionals with lower computational cost compared to the linear response approach. Note that the band gaps calculated by BOD are somewhat different from that of hybrid functionals by simply applying the same U/V parameters as in the case of surface slabs and interfaces, which suggests that the transferability of U/V from the bulk models to slabs and interfaces is not as well as expected. BOD is extended to calculate the U/V parameters for slabs and interfaces and reach similar results as bulk solids. Moreover, we find that the U/V are reasonably transferable between surface slabs and interfaces with different thicknesses under various effects of quantum confinement, which contributes to fast access to the electronic properties of large-scale systems with higher accuracy.
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The fluid in the annulus is in a variable mass flow state under the lost circulation condition, significantly affecting wellbore pressure distribution and the heat transfer efficiency between wellbore and formation. Therefore, based on the hydrodynamics and energy conservation law, a coupling model of transient wellbore temperature and pressure field under lost circulation conditions is established, which fully considers the casing program, bottom hole assembly, and heat source generated in drilling, as well as the influence of the temperature and pressure coupling in wellbore on the physical parameters of drilling fluid. The calculation results of the model in this paper are in good agreement with the field measured data and the previous research results, which verifies the rationality and accuracy of the model in this paper. The effects of the loss rate and the lost circulation zone location on the wellbore temperature and pressure distribution are analyzed, and the variation rule of the physical parameters of drilling fluid under the lost circulation condition is studied. The numerical simulation results show that the density and viscosity of drilling fluid in the annulus and bottom hole pressure increase with the increase in the circulation time; the annulus temperature decreases gradually with the increase in cycle time and tends to become stable after 8 h of the cycle. The annulus temperature and bottom hole pressure decrease with the increase in loss rate and closeness of the loss zone to the well bottom. When the loss zone is in the upper open-hole section, an inflection point consistent with the location of the loss zone appears on the annular temperature difference curve between the loss circulation and the nonloss circulation, and the position of the loss zone can be judged according to the inflection point.
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With the rapid development of information and communication technology (ICT), social media-based donation platforms emerged. These platforms innovatively demonstrate peer information (e.g., number of donated peers) on the donation page, which inevitably brings the peer influence into donors' donation decision process. However, how the peer influence will affect the psychological process of donation decisions are remained unknown. This study used the number of donated peers to examine the effects of peer influence on donors' donation decisions and extracted event-related potential (ERP) from electroencephalographic data to explore the underlying psychological process. The behavioral results indicated that the number of donated peers positively influenced donors' willingness to donate. The ERP results suggested that a larger number of donated peers might indicate a higher level of conformity and greater perceived emotional rewards, as a larger P2 amplitude was observed. Following the early processing of emotional stimuli, cognitive detection of decisional risk took place, and the donors reckoned a smaller number of donated peers as a high potential risk, which was reflected by a larger N2 amplitude. In the later stage, the larger number of donated peers, which represented a higher magnitude of prospective emotional rewards, led to a higher incentive to donate, and reflected in a larger amplitude of P3. Additionally, implications and future directions were discussed.
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[This corrects the article DOI: 10.1021/acsomega.2c04185.].
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BACKGROUND: Intervertebral disc degeneration (IDD) is a natural progression of age-related processes. Associated with IDD, degenerative disc disease (DDD) is a pathologic condition implicated as a major cause of chronic lower back pain, which can have a severe impact on the quality of life of patients. As degeneration progression is associated with elevated levels of inflammatory cytokines, enhanced aggrecan and collagen degradation, and changes in the disc cell phenotype. The purpose of this study was to investigate the biological and cytological characteristics of rabbit nucleus pulposus mesenchymal stem cells (NPMSCs)-a key factor in IDD-and to determine the effect of the growth and differentiation factor-5 (GDF5) on the differentiation of rabbit NPMSCs transduced with a lentivirus vector. METHODS: An in vitro culture model of rabbit NPMSCs was established and NPMSCs were identified by flow cytometry (FCM) and quantitative real-time PCR (qRT-PCR). Subsequently, NPMSCs were randomly divided into three groups: a transfection group (the lentiviral vector carrying GDF5 gene used to transfect NPMSCs); a control virus group (the NPMSCs transfected with an ordinary lentiviral vector); and a normal group (the NPMSCs alone). FCM, qRT-PCR, and western blot (WB) were used to detect the changes in NPMSCs. RESULTS: The GDF5-transfected NPMSCs displayed an elongated shape, with decreased cell density, and significantly increased GDF5 positivity rate in the transfected group compared to the other two groups (P < 0.01). The mRNA levels of Krt8, Krt18, and Krt19 in the transfected group were significantly higher in comparison with the other two groups (P < 0.01), and the WB results were consistent with that of qRT-PCR. CONCLUSIONS: GDF5 could induce the differentiation of NPMSCs. The lentiviral vector carrying the GDF5 gene could be integrated into the chromosome genome of NPMSCs and promoted differentiation of NPMSCs into nucleus pulposus cells. Our findings advance the development of feasible and effective therapies for IDD.
Assuntos
Regulação da Expressão Gênica , Fator 5 de Diferenciação de Crescimento/genética , Infecções por Lentivirus/virologia , Lentivirus , Células-Tronco Mesenquimais/citologia , Núcleo Pulposo/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Modelos Animais de Doenças , Fator 5 de Diferenciação de Crescimento/biossíntese , Infecções por Lentivirus/metabolismo , Infecções por Lentivirus/patologia , Células-Tronco Mesenquimais/virologia , Núcleo Pulposo/patologia , Núcleo Pulposo/virologia , CoelhosRESUMO
Objective: This study was designed to compare the biomechanical properties of lumbar spondylolysis repairs using different fixation methods by using three-dimensional finite element analysis. Methods: Five finite element models (A, B, C, D, and E) of L4-S1 vertebral body were reconstructed by CT images of a male patient (A: intact model; B: spondylolysis model; C: spondylolysis model with intrasegmental direct fixation by Buck screw; D: spondylolysis model with intersegmental indirect fixation by pedicle screw system; E: spondylolysis model with hybrid internal fixation). L5-S1 level was defined as the operative level. After the intact model was verified, six physiological motion states were simulated by applying 500 N concentrated force and 10 Nm torque on the upper surface of L4. The biomechanical properties of the three different internal fixation methods were evaluated by comparing the range of motion (ROM), maximum stress, and maximum displacement. Results: Compared with Model B, the ROM and maximum displacement of Model C, D, and E decreased. The maximum stress on L5/S1 disc in models A, B, and C was much higher than that in Model D and E under extension and lateral bending conditions. Under axial rotation and lateral bending conditions, the maximum stress of interarticular muscle and internal fixation system in Model B and Model C was significantly higher than that in Model D and Model E. In contrast to Model D, the stress in Model E was distributed in two internal fixation systems. Conclusion: In several mechanical comparisons, hybrid fixation had better biomechanical properties than other fixation methods. The experimental results show that hybrid fixation can stabilize the isthmus and reduce intervertebral disc stress, which making it the preferred treatment for lumbar spondylolysis.
RESUMO
Objective: To investigate the expression and clinical significance of sperm-associated antigen 6 and NM23 proteins in human osteosarcoma. Methods: The specimens of conventional osteosarcoma with follow-up from 42 Chinese patients were analyzed in this study, and 12 cases of osteochondroma were considered controls. The expression of SPAG6 and NM23 was inspected using immunohistochemical staining, qRT-PCR, and Western blotting methods. Results: The positive expression rate of SPAG6 protein (71.43%) in 42 cases of osteosarcoma tissue was significantly higher than that (33.33%) in 12 cases of osteochondroma tissues (p < 0.05), while the positive rate of NM23 protein (35.71%) in osteosarcoma tissue was lower than that (58.33%) in osteochondroma tissue (p < 0.05). The mRNA and protein levels of SPAG6 were significantly higher than those of the adjacent normal tissues, while the expression of NM23 was lower in osteosarcoma tissues than that in the controls (p < 0.05 for all). There was a positive relationship between the expression of SPAG6 and pathological grade, metastasis, and Enneking stage (p < 0.05 for all). The overall survival rate of osteosarcoma patients with SPAG6 positive expression was significantly lower than that with SPAG6 negative expression. The relationship between the expression of NM23 and pathological grade, metastasis, and Enneking stage was negative (p < 0.05 for all). The overall survival rate of the osteosarcoma patients with NM23 positive expression was higher than that of the patients with NM23 negative expression (p < 0.05). Conclusion: Overexpression of SPAG6 and low expression of NM23 are negatively related to pathological grade, metastasis, and Enneking stage and prognosis of osteosarcoma patients. This suggested that SPAG6 and NM23 should be considered candidate prognostic biomarkers for patients with osteosarcoma.