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Oncogenic RAS-induced senescence (OIS) is an autonomous tumour suppressor mechanism associated with premalignancy1,2. Achieving this phenotype typically requires a high level of oncogenic stress, yet the phenotype provoked by lower oncogenic dosage remains unclear. Here we develop oncogenic RAS dose-escalation models in vitro and in vivo, revealing a RAS dose-driven non-linear continuum of downstream phenotypes. In a hepatocyte OIS model in vivo, ectopic expression of NRAS(G12V) does not induce tumours, in part owing to OIS-driven immune clearance3. Single-cell RNA sequencing analyses reveal distinct hepatocyte clusters with typical OIS or progenitor-like features, corresponding to high and intermediate levels of NRAS(G12V), respectively. When titred down, NRAS(G12V)-expressing hepatocytes become immune resistant and develop tumours. Time-series monitoring at single-cell resolution identifies two distinct tumour types: early-onset aggressive undifferentiated and late-onset differentiated hepatocellular carcinoma. The molecular signature of each mouse tumour type is associated with different progenitor features and enriched in distinct human hepatocellular carcinoma subclasses. Our results define the oncogenic dosage-driven OIS spectrum, reconciling the senescence and tumour initiation phenotypes in early tumorigenesis.
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Purpose: The study aims to develop a finite element model of the pelvic floor and thighs of elderly men to quantitatively assess the impact of different pelvic floor muscle trainings and the urinary and defecation control ability. Methods: A finite element model of the pelvic floor and thighs of elderly men was constructed based on MRI and CT. Material properties of pelvic floor tissues were assigned through literature review, and the relative changes in waistline, retrovesical angle (RVA) and anorectad angulation (ARA) to quantitatively verify the effectiveness of the model. By changing the material properties of muscles, the study analyzed the muscle strengthening or impairment effects of the five types of rehabilitation training for four types of urination and defecation dysfunction. The changes in four outcome indicators, including the retrovesical angle, anorectad angulation, stress, and strain, were compared. Results: This study indicates that ARA and RVA approached their normal ranges as material properties changed, indicating an enhancement in the urinary and defecation control ability, particularly through targeted exercises for the levator ani muscle, external anal sphincter, and pelvic floor muscles. This study also emphasizes the effectiveness of personalized rehabilitation programs including biofeedback, exercise training, electrical stimulation, magnetic stimulation, and vibration training and advocates for providing optimized rehabilitation training methods for elderly patients. Discussion: Based on the results of computational biomechanics, this study provides foundational scientific insights and practical recommendations for rehabilitation training of the elderly's urinary and defecation control ability, thereby improving their quality of life. In addition, this study also provides new perspectives and potential applications of finite element analysis in elderly men, particularly in evaluating and designing targeted rehabilitation training.
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Background and Objective: Colorectal cancer (CRC), a leading global malignancy, continues to challenge the medical community. Despite advancements in surgical, chemotherapeutic, radiation, targeted, and immunotherapeutic strategies, issues like resistance and side effects persist. This review illuminates the potential of ferroptosis, an emerging non-apoptotic cell death form, and graphene oxide (GO), with its distinctive physicochemical properties, in CRC therapy. Methods: The databases search included PubMed, Medline and Web of Science. Search terms focused on CRC, graphene, GO, ferroptosis, and related aspects in therapy and drug delivery. The time frame for literature retrieval was up to April 2024. Studies in languages other than English were excluded. Key Content and Findings: Ferroptosis has been recognized for its role in addressing treatment resistance, a notable hurdle in effective CRC management. This form of cell death offers a promising avenue for enhancing the effectiveness of existing treatments. However, understanding its mechanisms and clinical implications in CRC remains an area of active research, with significant progress required for its practical application. Simultaneously, GO, a versatile two-dimensional material, has demonstrated substantial potential in biomedical applications, especially in cancer therapy. Its high specific surface area and unique π-electron domains facilitate the effective binding of chemotherapy drugs, target genes, and photosensitizers. This makes GO a promising candidate in cancer diagnosis and treatment, particularly through tumor photothermal and photodynamic therapy (PDT). Despite these advancements, GO's clinical application faces challenges, including in vitro cytotoxicity and decreased biodegradability, necessitating further research. Conclusions: This review focuses on the characteristics of GO and ferroptosis, as well as their applications in tumor diagnosis and treatment, with a particular emphasis on their potential in CRC.
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Staphylococcal Enterotoxin Type B (SEB), produced by Staphylococcus aureus bacteria, is notorious for inducing severe food poisoning and toxic shock syndrome. While nanobody-based treatments hold promises for combating SEB-induced diseases, the lack of structural information between SEB and nanobodies has hindered the development of nanobody-based therapeutics. Here, we present crystal structures of SEB-Nb3, SEB-Nb6, SEB-Nb8, SEB-Nb11, and SEB-Nb20 at resolutions ranging from 1.59 Å to 2.33 Å. Crystallographic analysis revealed that Nb3, Nb8, Nb11, and Nb20 bind to SEB at the T-cell receptor (TCR) interface, while Nb6 binds at the major histocompatibility complex (MHC) interface, suggesting their potential to inhibit SEB function by disrupting interactions with TCR or MHC molecules. Molecular biological analyses confirmed the thermodynamic and kinetic parameters of Nb3, Nb5, Nb6, Nb8, Nb11, Nb15, Nb18, and Nb20 to SEB. The competitive inhibition was further confirmed by cell-based experiments demonstrating nanobody neutralization. These findings elucidate the structural basis for developing specific nanobodies to neutralize SEB threats, providing crucial insights into the underlying mechanisms and offering significant assistance for further optimization towards future therapeutic strategies.
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The effective management of moderate to severe pain often relies on the use of analgesic agents. However, the widespread utility of these medications is hindered by the occurrence of several undesirable side effects. In light of this challenge, there is growing interest in the development of κ opioid receptor (KOR) agonists, which have shown promise in mitigating these adverse effects. In this study, leveraging the structural scaffold of compound D (our previous study), we embarked on the design, synthesis, and evaluation of a series of N'-benzyl-3-chloro-N- ((1S,3R,4R)-3-((dimethylamino)methyl)-4-hydroxy-4-(3-methoxyphenyl)cyclohexyl)benzenesulfonamide derivatives. These compounds were subjected to comprehensive in vitro and in vivo test. Through systematic structure-activity relationship (SAR) exploration, we successfully identified compound 23p (Ki(KOR):1.9 nM) as a highly selective KOR ligand of new chemotype. 23p showed high clearance in vitro PK test, and abdominal contraction test showed potent antinociceptive effect. 23p and its O-demethyl metabolite 25 were both found in the plasma of mouse, 25 also showed potent affinity toward KOR (Ki(KOR): 3.1 nM), both they contribute to the analgesic effect. Moreover, 23p exhibited potent antinociceptive activity in abdominal constriction test, which was effectively abolished by pre-treatment of nor-BNI, a selective KOR antagonist.
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Benzenossulfonamidas , Receptores Opioides kappa , Sulfonamidas , Animais , Relação Estrutura-Atividade , Sulfonamidas/química , Sulfonamidas/farmacologia , Sulfonamidas/síntese química , Ligantes , Receptores Opioides kappa/metabolismo , Receptores Opioides kappa/antagonistas & inibidores , Camundongos , Masculino , Estrutura Molecular , Humanos , Descoberta de Drogas , Relação Dose-Resposta a Droga , Analgésicos/farmacologia , Analgésicos/química , Analgésicos/síntese química , RatosRESUMO
The correlation between lower psoas mass and the prognosis of osteoporotic vertebral compression fractures (OVCF) is still unclear. This study aims to investigate the impact of lower psoas mass on the prognosis of patients undergoing percutaneous vertebroplasty (PVP). One hundred and sixty-three elderly patients who underwent single-segment PVP from January 2018 to December 2021 were included. The psoas to L4 vertebral index (PLVI) via MRI were measured to assess psoas mass. Patients were divided into high PLVI (> 0.79) and low PLVI (≤ 0.79) groups based on the median PLVI in the cohort. The basic information (age, gender, body mass index (BMI) and bone mineral density (BMD)), surgical intervention-related elements (duration of operation, latency to ambulation, period of hospital stay, and surgical site), postoperative clinical outcomes (Visual Analog Scale (VAS) scores, Oswestry Disability Index (ODI) scores, Japanese Orthopaedic Association (JOA) scores), and incidence of secondary fractures) were compared. Patients showed no statistically significant differences in terms of age, gender, surgical sute, BMI, BMD and preoperative VAS, ODI, JOA scores (P > 0.05) between the two groups. However, there were significant differences in terms of latency to ambulation, period of hospital stay (P < 0.05). VAS, ODI, and JOA scores at 1, 6, and 12 months after surgery showed that the high PLVI group had significantly better outcomes than the low PLVI group (P < 0.05). Additionally, the low PLVI group had a significantly higher incidence of recurrent fracture (P < 0.05). Lower psoas mass can reduce the clinical effect of PVP in patients with osteoporotic vertebral compression fractures, and is a risk factor for recurrent vertebral fracture.
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Fraturas por Compressão , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Masculino , Feminino , Idoso , Vertebroplastia/métodos , Fraturas por Compressão/cirurgia , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Prognóstico , Idoso de 80 Anos ou mais , Músculos Psoas/diagnóstico por imagem , Resultado do Tratamento , Densidade Óssea , Estudos RetrospectivosRESUMO
Proteins and nucleic-acids are essential components of living organisms that interact in critical cellular processes. Accurate prediction of nucleic acid-binding residues in proteins can contribute to a better understanding of protein function. However, the discrepancy between protein sequence information and obtained structural and functional data renders most current computational models ineffective. Therefore, it is vital to design computational models based on protein sequence information to identify nucleic acid binding sites in proteins. Here, we implement an ensemble deep learning model-based nucleic-acid-binding residues on proteins identification method, called SOFB, which characterizes protein sequences by learning the semantics of biological dynamics contexts, and then develop an ensemble deep learning-based sequence network to learn feature representation and classification by explicitly modeling dynamic semantic information. Among them, the language learning model, which is constructed from natural language to biological language, captures the underlying relationships of protein sequences, and the ensemble deep learning-based sequence network consisting of different convolutional layers together with Bi-LSTM refines various features for optimal performance. Meanwhile, to address the imbalanced issue, we adopt ensemble learning to train multiple models and then incorporate them. Our experimental results on several DNA/RNA nucleic-acid-binding residue datasets demonstrate that our proposed model outperforms other state-of-the-art methods. In addition, we conduct an interpretability analysis of the identified nucleic acid binding residue sequences based on the attention weights of the language learning model, revealing novel insights into the dynamic semantic information that supports the identified nucleic acid binding residues. SOFB is available at https://github.com/Encryptional/SOFB and https://figshare.com/articles/online_resource/SOFB_figshare_rar/25499452 .
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Aprendizado Profundo , Sítios de Ligação , Ácidos Nucleicos/metabolismo , Ácidos Nucleicos/química , Proteínas/química , Proteínas/metabolismo , Proteínas/genética , Ligação Proteica , Biologia Computacional/métodosRESUMO
Cerebral ischemic stroke remains a leading cause of mortality and morbidity worldwide. Toll-like receptor 4 (TLR4) has been implicated in neuroinflammatory responses poststroke, particularly in the infiltration of immune cells and polarization of macrophages. This study aimed to elucidate the impact of TLR4 deficiency on neutrophil infiltration and subsequent macrophage polarization after middle cerebral artery occlusion (MCAO), exploring its role in stroke prognosis. The objective was to investigate how TLR4 deficiency influences neutrophil behavior poststroke, its role in macrophage polarization, and its impact on stroke prognosis using murine models. Wild-type and TLR4-deficient adult male mice underwent MCAO induction, followed by various analyses, including flow cytometry to assess immune cell populations, bone marrow transplantation experiments to evaluate TLR4-deficient neutrophil behaviors, and enzyme-linked immunosorbent assay and Western blot analysis for cytokine and protein expression profiling. Neurobehavioral tests and infarct volume analysis were performed to assess the functional and anatomical prognosis poststroke. TLR4-deficient mice exhibited reduced infarct volumes, increased neutrophil infiltration, and reduced M1-type macrophage polarization post-MCAO compared to wild-type mice. Moreover, the depletion of neutrophils reversed the neuroprotective effects observed in TLR4-deficient mice, suggesting the involvement of neutrophils in mediating TLR4's protective role. Additionally, N1-type neutrophils were found to promote M1 macrophage polarization via neutrophil gelatinase-associated lipocalin (NGAL) secretion, a process blocked by TLR4 deficiency. The study underscores the protective role of TLR4 deficiency in ischemic stroke, delineating its association with increased N2-type neutrophil infiltration, diminished M1 macrophage polarization, and reduced neuroinflammatory responses. Understanding the interplay between TLR4, neutrophils, and macrophages sheds light on potential therapeutic targets for stroke management, highlighting TLR4 as a promising avenue for intervention in stroke-associated neuroinflammation and tissue damage.
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Macrófagos , Infiltração de Neutrófilos , Acidente Vascular Cerebral , Receptor 4 Toll-Like , Animais , Masculino , Camundongos , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Macrófagos/metabolismo , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/metabolismo , Neutrófilos/imunologia , Prognóstico , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Receptor 4 Toll-Like/deficiência , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismoRESUMO
Temporal interference (TI) as a new neuromodulation technique can be applied to non-invasive deep brain stimulation. In order to verify its effectiveness in the regulation of motor behavior in animals, this paper uses the TI method to focus the envelope electric field to the ventral posterior lateral nucleus (VPL) of the thalamus in the deep brain of mouse to regulate left- and right-turning motor behavior. The focusability of TI in the mouse VPL was analyzed by finite element method, and the focus area and volume were obtained by numerical calculation. A stimulator was used to generate TI current to stimulate the mouse VPL to verify the effectiveness of the TI stimulation method, and the accuracy of the focus location was further determined by c-Fos immunofluorescence experiments. The results showed that the electric field generated by TI stimulation was able to focus on the VPL nuclei when the stimulation current reached 800 µA; the mouse were able to make corresponding left and right turns according to the stimulation position; and the c-Fos positive cell markers in the VPL nuclei increased significantly after stimulation. This study confirms the feasibility of TI in regulating animal motor behavior and provides a non-invasive stimulation method for brain tissue for animal robots.
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Estimulação Encefálica Profunda , Atividade Motora , Proteínas Proto-Oncogênicas c-fos , Animais , Camundongos , Estimulação Encefálica Profunda/métodos , Atividade Motora/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Comportamento Animal , Núcleos Ventrais do Tálamo/fisiologia , Análise de Elementos FinitosRESUMO
Antibiotic resistance genes (ARGs) can be emitted from wastewater to ambient air and impose unignorable inhalable hazards, which could be exacerbated in antibiotic-concentrated hospital sewage. However, whether the ARG-carrying pathogens are more likely to infect cells remains largely unknown. Here, this study investigated and analyzed the spatiotemporal distribution, interaction, and toxicity of airborne microorganisms and their hosting ARGs in a hospital sewage treatment facility. The average concentration of ARGs/MGEs in sewage of bioreaction tank (BRT-W) was 2.27 × 104 gene copies/L. In the air of bioreaction tank (BRT-A), the average concentration of ARGs/MGEs was 15.86 gene copies/m3. In the four seasons, the ARGs concentration of sewage gradually decreased over time; The concentration of ARGs in the air first decreased and then increased. In spring, the concentration of ARGs/MGEs (qacedelta1-01) in BRT-W was highest (1.05 × 105 gene copies/L); The concentration of ARGs/MGEs (strB) in BRT-A in winter was higher than other seasons (26.18 gene copies/m3). Different from the past, this study also paid attention to the pathogenic potential of ARGs/MGEs in the air. The results of cell experiments showed that the cytotoxicity of drug-resistant Escherichia coli could reach Grade V. This suggested that the longer the drug-resistant E. coli were exposed to cells, the greater the cytotoxicity. Moreover, the cytotoxicity of bacteria increased with the increase in exposure time. In spring, the toxic effect of ARGs/MGEs in sewage of BRT-W was highest. Traceability analysis proved that BRT-W was an essential source of microorganisms and ARGs/MGEs in BRT-A. Furthermore, the combined risk of people exposed to the air of BRT in spring was higher than that in other seasons.
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Genes Bacterianos , Esgotos , Humanos , Esgotos/microbiologia , Antibacterianos/análise , Escherichia coli/genética , Resistência Microbiana a Medicamentos/genética , HospitaisRESUMO
Central sarcopenia is associated with the prognosis of various orthopedic surgeries in the elderly. This study aims to investigate its impact on the outcomes of single-segment lumbar fusion surgery in elderly patients. Retrospective analysis was conducted on 314 patients aged 60 to 80 who underwent single-segment posterior lumbar fusion surgery due to degenerative lumbar diseases. Patients were categorized into high psoas and L4 vertebral index (PLVI) and low PLVI groups according to the MRI-measured PLVI for central sarcopenia. Basic patient data, surgery-related parameters, functional assessments at preoperative and postoperative 3, 6, and 12 months, and X-ray-based fusion status were compared. The basic data of the two groups showed no significant differences. Parameters including the operative segment, preoperative hemoglobin levels, surgical duration, and intraoperative blood loss exhibited no significant variances. However, notable differences were observed in postoperative initial hemoglobin levels, transfusion requirements, and length of hospital stay between the two groups. During the postoperative follow-ups at 3, 6, and 12 months, the VAS scores for lower back pain and ODI scores in the lower PLVI group were significantly higher compared to the high PLVI group. Additionally, the EuroQoL 5D scores were notably lower in the low PLVI group. There were no significant differences between the groups in terms of leg pain VAS scores at each time point and the fusion status at 12 months postoperatively. MRI-based central sarcopenia has a negative impact on the therapeutic effectiveness following single-segment lumbar fusion surgery in elderly patients.
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Sarcopenia , Fusão Vertebral , Idoso , Humanos , Estudos Retrospectivos , Sarcopenia/etiologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética , Hemoglobinas , Fusão Vertebral/efeitos adversos , Resultado do TratamentoRESUMO
During the COVID-2021 epidemic, a large number of antibiotics were used for clinical treatment in hospitals or daily prevention. Sewage from hospital sewage treatment centers (HSTC) and wastewater treatment plants (WWTP) produced a lot of antibiotic-resistance genes/mobile genetic elements (ARGs/MGEs). In this study, the sewage and bioaerosol in the biochemical tank (BT) of an HSTC and a WWTP were sampled throughout the year. The results showed that the average absolute abundance of sewage in BT of WWTP (BTW-W) was higher than sewage in BT of HSTC (BTW-H). Sewage was an important source of microorganisms and ARGs/MGEs in the air of BT. Microorganisms and MGEs were the factors affecting the differences in ARGs/MGEs. Cytotoxicity experiment proved that the cytotoxicity changed from Grade III to Grade IV with the increase in drug-resistant Escherichia coli concentration. According to the formation mechanism formula, the average generation rate of ARGs/MGEs in BT of HSTC was lower than that in WWTP. The diffusion range of ARGs/MGEs of HSTC was larger than that of WWTP. According to the above results, this study found that when people were far away from BT, the health risk of HSTC caused by the diffusion of bioaerosol was higher than WWTP; When people were close to BT, the health risk of WWTP was higher than HSTC due to the aeration of BT. This study provided a basis for public protection of ARGs. In the future, the elimination of airborne ARGs and crowd protection can be further studied in detail.
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COVID-19 , Esgotos , Humanos , Genes Bacterianos , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genéticaRESUMO
Spinal cord injury (SCI) causes neuroinflammation, neuronal death, and severe axonal connections. Alleviating neuroinflammation, protecting residual cells and promoting neuronal regeneration via endogenous neural stem cells (eNSCs) represent potential strategies for SCI treatment. Extracellular vesicles (EVs) released by mesenchymal stem cells have emerged as pathological mediators and alternatives to cell-based therapies following SCI. In the present study, EVs isolated from untreated (control, C-EVs) and TGF-ß1-treated (T-EVs) mesenchymal stem cells were injected into SCI mice to compare the therapeutic effects and explore the underlying mechanisms. Our study demonstrated for the first time that the application of T-EVs markedly enhanced the proliferation and antiapoptotic ability of NSCs in vitro. The infusion of T-EVs into SCI mice increased the shift from the M1 to M2 polarization of reactive microglia, alleviated neuroinflammation, and enhanced the neuroprotection of residual cells during the acute phase. Moreover, T-EVs increased the number of eNSCs around the epicenter. Consequently, T-EVs further promoted neurite outgrowth, increased axonal regrowth and remyelination, and facilitated locomotor recovery in the chronic stage. Furthermore, the use of T-EVs in Rictor-/- SCI mice (conditional knockout of Rictor in NSCs) showed that T-EVs failed to increase the activation of eNSCs and improve neurogenesis sufficiently, which suggested that T-EVs might induce the activation of eNSCs by targeting the mTORC2/Rictor pathway. Taken together, our findings indicate the prominent role of T-EVs in the treatment of SCI, and the therapeutic efficacy of T-EVs for SCI treatment might be optimized by enhancing the activation of eNSCs via the mTORC2/Rictor signaling pathway.
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BACKGROUND: With the successful development of modern immunotherapy, immune checkpoint inhibitors (ICIs) are currently considered potential therapeutic options for patients with cancer. However, the therapeutic potential of ICIs in human cancer is mainly limited by their systemic toxicity and low response rate, which suggests the necessity of local drug delivery with an effective vector and reshaping the immunosuppressive tumor microenvironment (TME) to enhance ICI therapy. Here, we constructed a novel double-gene recombinant oncolytic adenovirus named RCAd-LTH-shPD-L1 based on the RCAd virus platform armed with a DNA fragment encoding an anti-VEGF antibody and shRNA to inhibit PD-L1 expression. METHODS: The correct assembly of RCAd-LTH-shPD-L1 was characterized by analyzing its secretion, antigen specificity, and replication using western blotting, ELISA and quantitative PCR, respectively. The in vitro effects of RCAd-LTH-shPD-L1 on cell proliferation, vasculogenic, and cell migration were assessed. Antitumor effects and therapeutic mechanisms were evaluated in vivo using immunodeficient and humanized immune system mouse models. The TME was studied by ELISA, immunohistochemistry and flow cytometry. RESULTS: RCAd-LTH-shPD-L1 cells secreted anti-VEGF antibodies and inhibited the expression of PD-L1 in cancer cells. Moreover, RCAd-LTH-shPD-L1 exerted a specific cytotoxic effect on human cancer cells, but not on murine cancer cells or normal human cells. RCAd-LTH-shPD-L1 elicited a more potent antitumor effect in an immunodeficient mouse model and a humanized immune system mouse model than RCAd-shPD-L1, as demonstrated by the significant decrease in tumor growth. Furthermore, RCAd-LTH-shPD-L1 modulated the TME, which led to lymphocyte infiltration and alteration of their immune phenotype, as characterized by downregulation of anoxic factor HIF-1α and angiogenesis marker CD31, upregulation of cytokine such as IFN-γ, IL-6 and IL-12. CONCLUSIONS: In summary, our data demonstrated that the localized delivery of anti-VEGF antibodies and shPD-L1 by engineered RCAd-LTH-shPD-L1 is a highly effective and safe strategy for cancer immunotherapy. Moreover, the data underscore the potential of combining local virotherapy and anti-angiogenic therapy with ICIs as an effective TME therapy for poorly infiltrating tumors.
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Antígeno B7-H1 , Neoplasias , Humanos , Animais , Camundongos , Antígeno B7-H1/metabolismo , Adenoviridae/genética , Adenoviridae/metabolismo , Microambiente Tumoral , Neoplasias/terapia , Neoplasias/metabolismo , Modelos Animais de Doenças , Linfócitos/metabolismoRESUMO
Before (2019), during (2020), and after (2021) the COVID-19 outbreak, different response methods and measures were taken on campuses to control the spread of COVID-19 within schools. These response methods may have changed the outdoor bioaerosol characteristics, which may affect staff and student health. Therefore, we analyzed the bacterial concentrations, particle size distribution, microbial populations, exposure risks, and environmental influences of bioaerosols at a campus before, during, and after the COVID-19 outbreak. This study used eight-stage Andersen samplers to collect and analyze culturable bacteria in bioaerosols from various locations, high-throughput sequencing to analyze microbial species, principal component analysis to compare differences in samples, RDA to investigate the effects of environmental factors on bioaerosols, and hazard quotient (HQ) and BugBase to evaluate human health risks. The study findings revealed that average bacterial concentrations before, during, and after COVID-19 were 75 CFU m-3, 136 CFU m-3, and 78 CFU m-3, respectively. Moreover, the average percentage of bacteria attached to PM2.5 was 49.2%, 42.7%, and 29.9%, respectively. High-throughput sequencing revealed that species composition changed significantly during the three years of COVID-19. The proportion of Pantoea and Bacillus increased with the development of COVID-19 and these became the dominant strains after COVID-19, whereas Pseudomonas had the maximum proportion during COVID-19. Both risk assessment and BugBase phenotype prediction results indicated that the potential pathogenic risk was the highest in the outdoor environment of the campus during COVID-19 and that bioaerosol contamination was the most severe compared to the outdoor bioaerosol characteristics of the campus recovered after COVID-19.
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Microbiologia do Ar , COVID-19 , Humanos , Tamanho da Partícula , Monitoramento Ambiental/métodos , Fungos , COVID-19/epidemiologia , Aerossóis e Gotículas Respiratórios , China/epidemiologia , BactériasRESUMO
MicroRNAs (miRNAs) are vital in regulating gene expression through binding to specific target sites on messenger RNAs (mRNAs), a process closely tied to cancer pathogenesis. Identifying miRNA functional targets is essential but challenging, due to incomplete genome annotation and an emphasis on known miRNA-mRNA interactions, restricting predictions of unknown ones. To address those challenges, we have developed a deep learning model based on miRNA functional target identification, named miTDS, to investigate miRNA-mRNA interactions. miTDS first employs a scoring mechanism to eliminate unstable sequence pairs and then utilizes a dynamic word embedding model based on the transformer architecture, enabling a comprehensive analysis of miRNA-mRNA interaction sites by harnessing the global contextual associations of each nucleotide. On this basis, miTDS fuses extended seed alignment representations learned in the multi-scale attention mechanism module with dynamic semantic representations extracted in the RNA-based dual-path module, which can further elucidate and predict miRNA and mRNA functions and interactions. To validate the effectiveness of miTDS, we conducted a thorough comparison with state-of-the-art miRNA-mRNA functional target prediction methods. The evaluation, performed on a dataset cross-referenced with entries from MirTarbase and Diana-TarBase, revealed that miTDS surpasses current methods in accurately predicting functional targets. In addition, our model exhibited proficiency in identifying A-to-I RNA editing sites, which represents an aberrant interaction that yields valuable insights into the suppression of cancerous processes.
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Aprendizado Profundo , MicroRNAs , MicroRNAs/genética , RNA Mensageiro/genética , Nucleotídeos , Edição de RNARESUMO
Zinc alloys have demonstrated considerable potentials as implant materials for biodegradable vascular and orthopedic applications. However, the high initial release of Zn2+ can trigger intense immune responses that impede tissue healing. To address this challenge and enhance the osteogenic capacity of zinc alloys, the surface of Zn1Mg was subjected to CO2 plasma modification (Zn1Mg-PP) followed by grafting with choline phosphate chitosan (Zn1Mg-PP-PCCs). This study aims to investigate the in vitro and in vivo biocompatibility of the surface-modified Zn1Mg. The effect of the surface modification on the inflammatory response and osteogenic repair process was investigated. Compared with unmodified Zn1Mg, the degradation rate of Zn1Mg-PP-PCCs was significantly decreased, avoiding the cytotoxicity triggered by the release of large amounts of Zn2+. Moreover, PCCs significantly enhanced the cell-material adhesion, promoted the proliferation of osteoblasts (MC3T3-E1) and upregulated the expression of key osteogenic factors in vitro. Notably, the in vivo experiments revealed that the surface modification of Zn1Mg suppressed inhibited the expression of inflammatory cytokines, promoting the secretion of anti-inflammatory factors, thereby reducing inflammation and promoting bone tissue repair. Furthermore, histological analysis of tissue sections exhibited strong integration between the material and the bone, along with well-defined new bone formation and reduced osteoclast aggregation on the surface. This was attributed to the improved immune microenvironment by PCCs, which promoted osteogenic differentiation of osteoblasts. These findings highlight that the preparation of PCCs coatings on zinc alloy surfaces effectively inhibited ion release and modulated the immune environment to promote bone tissue repair. STATEMENT OF SIGNIFICANCE: Surface modification of biodegradable Zn alloys facilitates the suppression of intense immune responses caused by excessive ion release concentrations from implants. We modified the surface of Zn1Mg with choline phosphate chitosan (PCCs) and investigated the effects of surface modification on the inflammatory response and osteogenic repair process. In vitro results showed that the PCCs coating effectively reduced the degradation rate of Zn1Mg to avoid cytotoxicity caused by high Zn2+ concentration, favoring the proliferation of osteoblasts. In addition, in vivo results indicated that Zn1Mg-PP-PCCs attenuated inflammation to promote bone repair by modulating the release of inflammation-related factors. The surface-modified Zn1Mg implants demonstrated strong osseointegration, indicating that the PCCs coating effectively modulated the immune microenvironment and promoted bone healing.
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Quitosana , Osteogênese , Humanos , Quitosana/farmacologia , Fosforilcolina , Ligas/farmacologia , Inflamação , Zinco/farmacologia , Materiais Revestidos Biocompatíveis/farmacologiaRESUMO
Intelligent monitoring approaches for long-term, real-time digitalization in structural health monitoring (SHM) are currently attracting significant interest. Among these, self-sensing cementitious composites stand out due to their easy preparation, cost-effectiveness, and excellent compatibility with concrete structures. However, the current research faces challenges, such as excessive conductive filler, difficulties in filler dispersion, and insufficient stress sensitivity and instability. This study presents a novel approach to these challenges by fabricating self-sensing cementitious sensors using silver nanoparticles (AgNPs), a new type of conductive filler. The percolation threshold of AgNPs in these materials was determined to be 0.0066 wt%, marking a reduction of approximately 90% compared to traditional conductive fillers. Moreover, the absorbance test with a UV spectrophotometer showed that AgNPs were well dispersed in an aqueous solution, which is beneficial for the construction of conductive pathways. Through various cyclic loading tests, it was observed that the self-sensing cementitious sensors with AgNPs exhibited robust pressure-sensitive stability. Additionally, their stress sensitivity reached 11.736, a value significantly surpassing that of conventional fillers. Regarding the conductive mechanism, when encountering the intricate environment within the cementitious material, AgNPs can establish numerous conductive pathways, ensuring a stable response to stress due to their ample quantity. This study provides a significant contribution to addressing the existing challenges in self-sensing cementitious materials and offers a novel reference for further research in this domain.
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Objective To explore the cell subsets and characteristics related to the prognosis of osteosarcoma by analyzing the cellular composition of tumor tissue samples from different osteosarcoma patients.Methods The single-cell sequencing data and bulk sequencing data of different osteosarcoma patients were downloaded.We extracted the information of cell samples for dimensionality reduction,annotation,and cell function analysis,so as to identify the cell subsets and clarify the cell characteristics related to the prognosis of osteosarcoma.The development trajectory of macrophages with prognostic significance was analyzed,and the prognostic model of osteosarcoma was established based on the differentially expressed genes of macrophage differentiation.Results The cellular composition presented heterogeneity in the patients with osteosarcoma.The infiltration of mononuclear phagocytes in osteosarcoma had prognostic significance(P=0.003).Four macrophage subsets were associated with prognosis,and their signature transcription factors included RUNX3(+),ETS1(+),HOXD11(+),ZNF281(+),and PRRX1(+).Prog_Macro2 and Prog_Macro4 were located at the end of the developmental trajectory,and the prognostic ability of macrophage subsets increased with the progression of osteosarcoma.The prognostic model established based on the differentially expressed genes involved in macrophage differentiation can distinguish the survival rate of osteosarcoma patients with different risks(P<0.001).Conclusion Macrophage subsets are closely related to the prognosis of osteosarcoma and can be used as the key target cells for the immunotherapy of osteosarcoma.