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With the increase of antimicrobial resistance, rapid antibiotic susceptibility testing (AST) to guide precise antibiotic administration has become increasingly important. However, current gold standard AST approaches tend to take up to 24-48 h. In this work, based on the nature of catalase-positive bacteria decomposing H2O2, we developed a rapid, portable, straightforward, and cost-effective phenotypic AST approach by detecting residual H2O2 using a Pt nanoparticles-based electrochemical sensor. The pulse current of the sensor exhibited a linear increase with rising H2O2 concentration, demonstrating a high sensitivity of â¼382.2 µA cm-2 mM-1. This approach showed superb diagnostic performance, with an area under the curve of 1 for 24 clinical samples of Escherichia coli and Staphylococcus aureus, with a total detection time of 60 and 45 min, respectively. Furthermore, the performance of the sensor showed no degradation even after 100 detections, promising a substantial reduction in AST costs. Overall, the proposed approach exhibited immense potential for diagnosing bacterial antibiotic resistance.
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Antibacterianos , Técnicas Eletroquímicas , Escherichia coli , Peróxido de Hidrogênio , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Platina , Staphylococcus aureus , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Platina/química , Nanopartículas Metálicas/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/análise , Técnicas Eletroquímicas/métodos , HumanosRESUMO
Background: More and more patients with pancreatic cancer (PC) received neoadjuvant therapy (NAT) and then underwent radical pancreatectomy. However, the benefit of adjuvant chemotherapy (AC) for these patients is still controversial. This study is designed to determine the benefits of postoperative AC for patients with PC undergoing NAT and radical resection. Methods: We conducted a comprehensive search of the PubMed, Embase, Web of Science, and Cochrane Library databases, covering the period from their inception until 10 September 2023. Our analysis focused on the assessment of overall survival (OS) and recurrence-free survival (RFS) through meta-analysis. The fixed-effects model and the random-effects model were used to process the data. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were employed to determine the necessary of administering AC for patients with PC who have undergone NAT and radical resection. We retrieved 3,063 search results, of which 3,048 were excluded because of duplication or after applying our inclusion and exclusion criteria. Results: A total of 15 studies with 21,113 patients (7,794 patients in the AC group and 13,319 in the non-AC group) were included, all of which reported OS, and three studies reported disease-free survival (DFS)/tumor-specific survival (CSS)/RFS. The final results showed that AC significantly improved OS and DFS/CSS/RFS in patients with PC who underwent pancreatectomy after NAT [OS: HR = 0.80, 95% CI (0.75â¼0.86), P < 0.00001, I2 = 48%; DFS/CSS/RFS: HR = 0.53, 95% CI (0.41~0.69), P < 0.00001, I2 = 0%]. Furthermore, we performed subgroup analyses and demonstrated that AC provided a significant survival benefit for patients with PC after NAT and resection regardless of the tumor size [<2-cm subgroup: HR = 0.72, 95% CI (0.5â¼0.94), P = 0.01; ≥2-cm subgroup: HR = 0.79, 95% CI (0.65â¼0.96), P = 0.02] and the margin status [R0 subgroup: HR = 0.83, 95% CI (0.77â¼0.88), P < 0.00001; R2 subgroup: HR = 0.75, 95% CI (0.61â¼0.92), P = 0.007]. AC also benefited the patients with a stage N0 [HR = 0.79, 95% CI (0.74~0.84), P < 0.00001], N1 [HR = 0.78, 95% CI (0.72â¼0.85), P < 0.00001], or poorly/undifferentiated tumor [HR = 0.76, 95% CI (0.66â¼0.87), P < 0.0001] in survival but not in patients with a stage N2 [HR = 0.69, 95% CI (0.43â¼1.09), P = 0.11] or well/moderately differentiated tumor [HR = 0.97, 95% CI (0.66â¼1.42), P = 0.87]. Conclusions: Although AC showed survival benefit for patients with PC undergoing radical pancreatectomy after NAT, we still need to consider the lymph node stage and the degree of differentiation of the tumor when we gave AC to a patient. High-quality prospective randomized controlled studies are required to well disclose the value of AC in patients with PC undergoing radical pancreatectomy after NAT. Systematic review registration: https://www.crd.york.ac.uk/prospero/ PROSPERO, identifier CRD42023461365.
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Using metagenomic sequencing we identified equine rotavirus group B (ERVB) of ruminant origin in foal diarrhea outbreaks in the 2021 foaling season. To further investigate ERVB occurrence and determine its environmental stability, we collected mare and foal fecal samples from different farms in Central Kentucky during the 2022 foaling season. The RT-qPCR-based analyses showed that ERVB genome was detected in 16.67â¯% (42/252) of surveyed mare samples and 26.56â¯% (34/128) of foal samples. Furthermore, 94.12â¯% (16/17) of collected soil samples and 100â¯% (13/13) of water samples obtained from the ERVB-positive farm premises also tested weakly positive. In addition, ERVB genome fragments were detected in 58.33â¯% (7/12) of indoor samples collected from the equipment/barn/hospital wards during the outbreak period. Finally, the seroprevalence study showed 87â¯% (113/130) of surveyed horse serum samples were positive for ERVB antibodies. Despite unsuccessful attempts in ERVB cultivation, phylogenetic analyses showed that fecal ERVB strains representing 2022 and 2023 foal diarrhea outbreaks, like 2021 strains, were more closely related to ruminant rotavirus B than other viruses. Further sequence analyses revealed that none of the three viral capsid proteins, the primary targets of virus-neutralizing antibodies, exhibited notable mutations among ERVB strains circulated over the past three years. Our data demonstrated that ERVB was widespread in horses on affected farms with extreme stability in the farm environment. These findings continue to support the need for future surveillance of ERVB in horses and the surrounding environment, and the development of effective countermeasures to protect horses against this new viral disease.
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Background: For glioma patients, the long-term advantages of dendritic cells (DCs) immunization remain unknown. It is extremely important to develop new treatment strategies that enhance the immunotherapy effect of DC-based vaccines. DCs exposed to glioma stem cells (GSCs) are considered promising vaccines against glioma. Methods: Glioma stem cells were isolated from mouse glioma GL261 cells (GCs). Both were subjected to severe (47°C) and mild (42°C) heat shock to induce immunogenic cell death (ICD). Membrane mobilization of calreticulin (CRT) and release of heat shock proteins (HSPs) were detected by flow cytometry. Dendritic cells were then exposed to heat-inactivated cells and co-culturing of T cells tested for immunotherapeutic efficacy in vitro. In vivo, we investigated the GSC targeting effect of the GSC-DC vaccine combined with CD47 blockade. Results: Heat shock induced ICD in GCs and GSCs, as indicated by significant release of calreticulin, HSP70, and HSP90. Heat shock condition ICD lysates induce maturation and activation-associated marker expression on monocyte-derived DCs. Accordingly, DCs pulsed with GCs and GSCs inactivated reduced colony formation, sphere formation, migration, and invasion of glioma and GSCs in vitro. Glioma stem cell-DC vaccine in combination with anti-CD47 antibody significantly enhanced survival in mice with glioma, induced production of interferon (IFN)-γ, and enhanced T-cell expansion in vivo. Of note, DCs pulsed with inactivated GSCs were more effective to control tumor growth than DCs pulsed with inactive GCs. Conclusions: Severe heat shock induces ICD in vitro. These data showed that administration of anti-CD47 antibody combined with GSC-DC vaccine may represent an effective immunotherapeutic strategy for cancer patients in clinical.
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p53, a tumor suppressor protein, has a vital role in the regulation of the cell cycle, apoptosis, and DNA damage repair. The degradation of p53 is predominantly controlled by the murine double minute 2 (MDM2) protein, a ubiquitin E3 ligase. The overexpression or amplification of MDM2 is commonly observed in various human cancers bearing wild-type p53 alleles, leading to the rapid degradation of the p53 protein and the attenuation of p53 tumor suppression functions. Thus, a major effort in p53-based cancer therapy has been to research MDM2 antagonists that specifically stabilize and activate p53, leading to the suppression of tumor growth. However, despite numerous efforts to develop MDM2 antagonists, to date they have failed to reach clinical use, largely because of the cytotoxicity associated with these small molecules. This study used our newly designed structure-based virtual screening approach on a commercial compound library to identify a novel compound, CGMA-Q18, which directly binds to MDM2, leading to the activation of p53, the induction of apoptosis, and cell cycle arrest in cancer cells. Notably, CGMA-Q18 significantly inhibited tumor xenograft growth in nude mice without observable toxicity. These findings highlight our useful virtual screening protocol and CGMA-Q18 as a putative MDM2 antagonist.
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BACKGROUND: Prostate cancer is a remarkable global health concern, necessitating accurate risk stratification for optimal treatment and outcome prediction. By highlighting the potential of imaging-based approaches to improve risk assessment in prostate cancer, this research aims to evaluate the diagnostic efficacy of the Prostate Imaging Reporting and Data System (PI-RADS) v2.1 combined with apparent diffusion coefficient (ADC) values to gain increased context within the broad landscape of clinical needs and advancements in prostate cancer management. METHODS: The clinical data of 145 patients diagnosed with prostate cancer were retrospectively analysed. The patients were divided into low-moderate- and high-risk groups on the basis of Gleason scores. PI-RADS v2.1 scores were assessed by senior radiologists and ADC values were calculated by using diffusion-weighted imaging. Statistical, univariate logistic regression, and receiver operating characteristic curve analyses were employed to evaluate the diagnostic efficacy of each index and combined PI-RADS v2.1 scores and ADC values. RESULTS: This study found significant differences in PI-RADS v2.1 scores and ADC values between the low-moderate- and high-risk groups (p < 0.001). Logistic regression analysis revealed associations of various clinical indicators, PI-RADS score and ADC values with Gleason risk classification. Amongst indices, mean ADC demonstrated the highest sensitivity (0.912) and area under curve (AUC) value (0.962) and the combination of PI-RADS v2.1 with mean ADC showed high predictive value for the Gleason risk grading of prostate cancer with a high AUC value (0.966). CONCLUSIONS: This study provides valuable evidence for the potential utility of imaging-based approaches, specifically PI-RADS v2.1 combined with ADC values, in enhancing the accuracy of risk stratification in prostate cancer.
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Gradação de Tumores , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Medição de Risco , Imagem de Difusão por Ressonância Magnética/métodosRESUMO
[This corrects the article DOI: 10.34133/bmr.0064.].
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Background: The capsid inhibitor (CAI) lenacapavir (LEN) was approved for use in 2022, yet there are few reports about its drug resistance mutations (DRMs) and sensitivity. Purpose: To delineate the prevalence of CAI DRMs and drug susceptibility among HIV-1 infected individuals living in Guangdong, China. Patients and Methods: A total of 1035 individuals with HIV-1 infection, including 660 highly Active Anti-Retroviral Therapy (HAART) naive individuals and 375 hAART experienced individuals whose protease (PR)/ reverse transcriptase (RT) fragments were amplified successfully during drug resistance surveillance between October 2021 and December 2023, were randomly included in this study. The entire HIV-1 gag gene was amplified from plasma in LEN-naive individuals with or without antiretroviral therapy. The epidemiological and demographic information of the enrolled individuals were collected. The Stanford HIV Drug Resistance Database HIVdb program for Capsid was used to interpret the CAI DRMs and the LEN susceptibility. Results: Among 1035 samples, 805 gag sequences were amplified, sequenced and assembled successfully from 518 hAART drugs naive individuals and 287 hAART drugs experienced individuals. Among them, 0.50% (4/805) carried at least one CAI DRM, of which 0.19% (1/518) from HAART naive individuals and 1.05% (3/287) from HAART experienced individuals. Among the individuals with CAI DRMs, two patients carried CAI major mutations (Q67H) conferring intermediate resistance to LEN and two patients carried CAI accessory mutation (T107A) conferring low level resistance to LEN. Conclusion: Extremely low prevalence of CAI DRMs was detected among people living with HIV (PLWH) in Guangdong, China. Our observations indicate that LEN application may be promising when used in clinical practice in China. Before the administration of LEN, there is no need to consider detecting CAI mutations in PLWH through DRM examination for the time being.
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BACKGROUND: Large Hemispheric Infarction (LHI) is a devastating disease with high mortality. This study aimed to use electroencephalography (EEG) to evaluate the death risk of LHI patients and identify suitable evaluation time. METHODS: This study retrospectively collected clinical and EEG data from 73 LHI patients, dividing them into death and survival group at discharge. EEG data was classified as 1-5 days and 6-14 days after onset according to the time intervals of cerebral edema. Regression and receiver operator characteristic curve (ROC) analysis were applied to explore the impact of temporal changes in various EEG and clinical features on death. RESULTS: The areas under ROC curve (AUC) of death prediction for non-α frequency on non-infarct side at 6-14 days after onset was significantly higher than that at 1-5 days (p = 0.004). And there was no significant difference between the AUC of seizure activity for death prediction at 1-5 days and 6-14 days (p = 0.418). Multivariate regression analysis revealed that non-α frequency on non-infarct side and seizure activity at 6-14 days after onset were the independent risk factors for the death of LHI patients. Additionally, above two EEG features significantly improved the death predictive efficacy of clinical features in LHI patients with the integrated discrimination improvement index (IDI) of 0.174 (p = 0.015) and the net reclassification improvement (NRI) of 1.314 (p<0.001). CONCLUSIONS: Non-α frequency on non-infarct side and seizure activity were reliable indicators for death prediction. 6-14 days after onset was the better time window for death evaluation of LHI patients through EEG.
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Lithium (Li) metal is an attractive anode material for use in high-energy lithium-sulfur and lithium-air batteries. However, its practical application is severely impeded by excessive dendrite growth, huge volume changes, and severe side reactions. Herein, a novel Li metal anode composed of lithiophilic two dimensional (2D) conjugated microporous polymer (Li-CMP) and reduced graphene oxide (rGO) sandwiches (Li-CMP@rGO) for Li metal batteries (LiMBs) is reported. In the Li-CMP@rGO anode, the conductive rGO facilitates the charge transfer while the functionalized-CMP provides Li nucleation sites within the micropores, thereby preventing dendrite growth. As a result, the Li-CMP@rGO anode can be cycled smoothly at 6 mA cm-2 of current density with a platting capacity of 2 mAh cm-2 for 1000 h. A Coulombic efficiency of 98.4% is achieved over 350 cycles with a low overpotential of 28 mV. In a full cell with LiFePO4 cathode, the Li-CMP@rGO anode also exhibited good cycling stability compared to CMP@rGO and CMP/Super-P. As expected, the simulation results reveal that Li-CMP@rGO has a strong affinity for Li ions compared to CMP@rGO. The strategies adopted in this work can open new avenues for designing hybrid porous host materials for developing safe and stable Li metal anodes.
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Ependymal cells are arranged along the inner surfaces of the ventricles and the central canal of the spinal cord, providing anatomical, physiological and immunological barriers that maintain cerebrospinal fluid (CSF) homeostasis. Based on this, studies have found that alterations in gene expression, cell junctions, cytokine secretion and metabolic disturbances can lead to dysfunction of ependymal cells, thereby participating in the onset and progression of central nervous system (CNS) infections. Additionally, ependymal cells can exhibit proliferative and regenerative potential as well as secretory functions during CNS injury, contributing to neuroprotection and post-injury recovery. Currently, studies on ependymal cell primarily focus on the basic investigations of their morphology, function and gene expression; however, there is a notable lack of clinical translational studies examining the molecular mechanisms by which ependymal cells are involved in disease onset and progression. This limits our understanding of ependymal cells in CNS infections and the development of therapeutic applications. Therefore, this review will discuss the molecular mechanism underlying the involvement of ependymal cells in CNS infections, and explore their potential for application in clinical treatment modalities.
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Infecções do Sistema Nervoso Central , Epêndima , Humanos , Epêndima/patologia , Epêndima/metabolismo , Animais , Infecções do Sistema Nervoso Central/terapiaRESUMO
BACKGROUND: Currently, the synthesis of compounds based on microbial cell factories is rapidly advancing, yet it encounters several challenges. During the production process, engineered strains frequently encounter disturbances in the cultivation environment or the impact of their metabolites, such as high temperature, acid-base imbalances, hypertonicity, organic solvents, toxic byproducts, and mechanical damage. These stress factors can constrain the efficiency of microbial fermentation, resulting in slow cell growth, decreased production, significantly increased energy consumption, and other issues that severely limit the application of microbial cell factories. RESULTS: This study demonstrated that sterol engineering in Kluyveromyces marxianus, achieved by overexpressing or deleting the coding genes for the last five steps of ergosterol synthase (Erg2-Erg6), altered the composition and ratio of sterols in its cell membrane, and affected its multiple tolerance. The results suggest that the knockout of the Erg5 can enhance the thermotolerance of K. marxianus, while the overexpression of the Erg4 can improve its acid tolerance. Additionally, engineering strain overexpressed Erg6 improved its tolerance to elevated temperature, hypertonic, and acid. YZB453, obtained by overexpressing Erg6 in an engineering strain with high efficiency in synthesizing xylitol, produced 101.22 g/L xylitol at 45oC and 75.11 g/L xylitol at 46oC. Using corncob hydrolysate for simultaneous saccharification and fermentation (SSF) at 46oC that xylose released from corncob hydrolysate by saccharification with hemicellulase, YZB453 can produce 45.98 g/L of xylitol, saving 53.72% of the cost of hemicellulase compared to 42oC. CONCLUSIONS: This study elucidates the mechanism by which K. marxianus acquires resistance to various antifungal drugs, high temperatures, high osmolarity, acidity, and other stressors, through alterations in the composition and ratio of membrane sterols. By employing sterol engineering, the fermentation temperature of this unconventional thermotolerant K. marxianus was further elevated, ultimately providing an efficient platform for synthesizing high-value-added xylitol from biomass via the SSF process at temperatures exceeding 45 °C.
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Fermentação , Kluyveromyces , Esteróis , Xilitol , Kluyveromyces/metabolismo , Kluyveromyces/genética , Xilitol/biossíntese , Xilitol/metabolismo , Esteróis/metabolismo , Esteróis/biossíntese , Engenharia Metabólica/métodos , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genéticaRESUMO
Many Asian American cancer patients face barriers to cancer care but little is known about their navigational needs. We designed and implemented a pilot study to provide culturally- and linguistically-appropriate navigation for Asian American cancer patients. We recruited Asian American adults age 21+ years, who spoke English, Cantonese, Mandarin, or Vietnamese, with newly diagnosed, stage I-III colorectal, liver, or lung cancer in the Northern California Bay Area. Participants were assigned a language-concordant patient navigator, who provided support and resources over 6 months. Surveys were administered at baseline, 3-, and 6-months to assess sociodemographic characteristics, healthcare access, quality of life (FACT-G), and cancer care needs. Participants' mean age was 65 years (range 38-81); 62% were men, 67% spoke Chinese, and 75% reported limited English proficiency. Forty-two percent of participants had lung, 38% colorectal, and 21% liver cancer. Of 24 participants who enrolled, 67% completed the program and 75% completed standard of care cancer treatment. The average total FACT-G score was 72.6 (SD 17) at baseline, 68.0 (SD 20) at 3 months, and 69.9 (SD 22) at 6 months. All participants reported that the program was culturally appropriate and would recommend it. Asian American cancer patients in a patient navigation program reported lower quality of life compared to the general adult cancer population. Even with navigation, 75% of participants reported completing standard of care treatment. While participants were satisfied with the program, more research is needed to address the quality of cancer care Asian American cancer patients receive.
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This study investigated the possible interaction between gut flora and miRNAs and the effect of both on anxiety disorders. The model group was induced with chronic restraint stress (CRS) and each group was tested for anxiety-like behaviour by open field test and elevated plus maze test. Meanwhile, the gut flora was analysed by 16S rRNA high-throughput sequencing. The miRNAs in hippocampus were analysed by high-throughput sequencing, and the key miRNAs were obtained by using the method of bioinformatics analysis. PCR was used to verify the significantly related key miRNAs. Spearman correlation analysis was used to explore the correlation between behaviour, key miRNAs and differential gut microbiota. The 16S rRNA high-throughput sequencing result showed that the gut flora was dysregulated in the model group. In particular, Verrucomicrobia, Akkermansia, Anaerostipes, Ralstonia, Burkholderia and Anaeroplasma were correlated with behaviour. The results of miRNA high-throughput sequencing analysis and bioinformatics analysis showed that 7 key miRNAs influenced the pathogenesis of anxiety, and qRT-PCR results were consistent with the high-throughput sequencing results. Mmu-miR-543-3p and mmu-miR-26a-5p were positively correlated with Verrucomicrobia, Akkermansia and Anaerostipes. Therefore, we infer that chronic stress caused the decrease of Akkermansia abundance, which may aggravate the decrease of mmu-miR-543-3p and mmu-miR-26a-5p expression, leading to the increase of SLC1A2 expression. In conclusion, gut flora has played an important influence on anxiety with changes in miRNAs.
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Background: Recent research has found a new way of cell death: disulfidptosis. Under glucose starvation, abnormal accumulation of disulfide molecules such as Cystine in Solute Carrier Family 7 Member 11 (SLC7A11) overexpression cells induced disulfide stress to trigger cell death. The research on disulfidptosis is still in its early stages, and its role in the occurrence and development of colorectal malignancies is still unclear. Method: In this study, we employed bioinformatics methods to analyze the expression and mutation characteristics of disulfidptosis-related genes (DRGs) in colorectal cancer. Consensus clustering analysis was used to identify molecular subtypes of Colorectal Adenocarcinoma (COAD) associated with disulfidptosis. The biological behaviors between subtypes were analyzed to explore the impact of disulfidptosis on the tumor microenvironment. Constructing and validating a prognostic risk model for COAD using diverse data. The influence of key genes on prognosis was evaluated through SHapley Additive exPlanations (SHAP) analysis, and the predictive capability of the model was assessed using Overall Survival analysis, Area Under Curve and risk curves. The immunological status of different patients and the prediction of drug treatment response were determined through immune cell infiltration, TMB, MSI status, and drug sensitivity analysis. Single-cell analysis was employed to explore the expression of genes at the cellular level, and finally validated the expression of key genes in clinical samples. Result: By integrating the public data from two platforms, we identified 2 colorectal cancer subtypes related to DRGs. Ultimately, we established a prognosis risk model for COAD using 7 genes (FABA4+GIPC2+EGR3+HOXC6+CCL11+CXCL10+ITLN1). SHAP analysis can further explained the positive or negative impact of gene expression on prognosis. By dividing patients into high-risk and low-risk groups, we found that patients in the high-risk group had poorer prognosis, higher TMB, and a higher proportion of MSI-H and MSI-L statuses. We also predicted that drugs such as 5-Fluorouracil, Oxaliplatin, Gefitinib, and Sorafenib would be more effective in low-risk patients, while drugs like Luminesib and Staurosporine would be more effective in high-risk patients. Single-cell analysis revealed that these 7 genes not only differ at the level of immune cells but also in epithelial cells, fibroblasts, and myofibroblasts, among other cell types. Finally, the expression of these key genes was verified in clinical samples, with consistent results. Conclusions: Our research findings provide evidence for the role of disulfidptosis in COAD and offer new insights for personalized and precise treatment of COAD.
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Adenocarcinoma , Neoplasias Colorretais , Microambiente Tumoral , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/mortalidade , Prognóstico , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenocarcinoma/mortalidade , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Biologia Computacional/métodos , Morte CelularRESUMO
Brain organoid models serve as a powerful tool for studying human brain development and function. Mass spectrometry imaging (MSI), a cutting-edge technology, allows us to map the spatial distribution of diverse molecules such as lipids, sugars, amino acids, drugs, and their metabolites within these organoids, all without the need for specific molecular probes. High-quality MSI data hinge on meticulous sample preparation. Fixatives play a pivotal role, but conventional options such as glutaraldehyde, paraformaldehyde, and cryopreserving such as sucrose may inadvertently impact tissue metabolites. Optimal fixation entails flash freezing in liquid nitrogen. However, for small organoids, a more suitable approach involves transitioning the organoids directly from the incubator into a warmed embedding solution, followed by freezing in dry ice-cooled ethanol. Another critical step is the embedding prior to cryosectioning, which also requires materials compatible with MSI, as traditional options can interfere with matrix deposition and ionization. Here, an optimized protocol for high resolution-MALDI-MSI of human brain organoids is presented, encompassing sample preparation, sectioning, and imaging using mass spectrometry. This method showcases the molecular distribution of small metabolites, such as amino acids, with high mass accuracy and sensitivity. As such, coupled with complementary studies of brain organoids, it can assist in illuminating complex processes governing early brain development, metabolic cell fate trajectories, and distinctive metabolite signatures. Furthermore, it provides insights into the precise locations of molecules within the organoid, enriching our understanding of the spatial organization of 3D brain organoid models. As the field continues to advance, a growing number of studies leveraging MSI to delve into brain organoids and complex biological systems is anticipated, thereby deepening the understanding of the metabolic aspects of human brain function and development.
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Encéfalo , Organoides , Humanos , Organoides/metabolismo , Organoides/citologia , Encéfalo/metabolismo , Encéfalo/citologia , Imagem Molecular/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Química Encefálica/fisiologia , Espectrometria de Massas/métodosRESUMO
Metal-organic frameworks (MOFs) have emerged as promising candidates for enzyme mimics due to their abundant pore structures and adjustable active sites. The catalytic activity particularly depends on the electronic character of the organic ligand. In this study, we report an iron-based MOF nanozyme FeTDC, created by replacing the 1,4-dicarboxybenzene ligand with five-membered 2,5-thiophenedicarboxylic acid (H2TDC). In comparison with the phenyl analogue, the sulfur-based heterocyclic ligand demonstrates high electron delocalization, and a low pKa value, which are beneficial for enhancing the metal/ligand interactions. Accordingly, FeTDC can facilitate the oxidation of the benzidine substrate in the presence of H2O2, thereby exhibiting remarkable peroxidase-like activity. The generation of hydroxyl radical (â¢OH) at the Fe active sites contributes to the catalytic process. Furthermore, the smartphone-assisted colorimetric assay of pyrophosphate was developed with high sensitivity, based on its inhibitory effect. When FeTDC was utilized for the removal of benzidine dye under high-salt condition, a 90 % of removal rate was achieved due to the synergistic effect of enzyme catalysis and physical adsorption. This work presents a novel perspective of heterocyclic effect on the design of MOF nanozymes, thereby expanding their applicability in the control of pollutants.
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The key aspect of the photoelectrochemical CO2 reduction reaction (PEC CO2 RR) lies in designing cathode materials that can generate high-energy photoelectrons, enabling the activation and conversion of CO2 into high-value products. In this study, a coaxially wrapped ZnO@ZnSe array heterostructure was synthesized using a simple anion exchange strategy and metallic Bi nanoparticles (NPs) were subsequently deposited on the surface to construct a Bi/ZnO@ZnSe photocathode with high CO2 conversion capability. This array photocathode possesses a large aspect ratio, which simultaneously satisfies a low charge carrier migration path and a large specific surface area that facilitates mass transfer. Additionally, the barrier formed at the n-n heterojunction interface hinders the transfer of high-energy photoelectrons from ZnSe to lower energy levels, resulting in their rapid capture by Bi while maintaining a relatively long lifetime. These captured electrons act as active sites, efficiently converting CO2 into CO with a Faradaic efficiency above 88.9% at -0.9 V vs. RHE and demonstrating superior stability. This work provides a novel approach for synthesizing high-energy photoelectrode materials with long lifetimes.
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Chronic obstructive pulmonary disease (COPD) is an irreversible and progressive chronic inflammatory lung disease which affects millions of people worldwide. Activated fibroblasts are observed to accumulate in lung of COPD patients and promote COPD progression through aberrant extracellular matrix (ECM) deposition. In this study, we identified that miR-1307-5p expression was significantly increased in lung fibroblasts derived from COPD patients. Mechanistically, we found that upregulation of miR-1307-5p promoted TGF-ß induced lung fibroblast activation and transdifferentiation. We also identified FBXL16 as a direct target for miR-1307-5p mediated myofibroblast activation in COPD. Knockdown of FBXL16 by siRNA prominently increased the expression of myofibroblast markers in MRC-5 fibroblasts after TGF-ß administration. Ectopic expression of FBXL16 in MRC-5 counteracted miR-1307-5p agomir-induced fibroblast transdifferentiation. Furthermore, We found that miR-1307-5p promoted pulmonary fibroblast transdifferentiation through FBXL16 regulated HIF1α degradation. In general, our findings indicate that miR-1307-5p is important for COPD pathogenesis, and may serve as a potential target for COPD treatment.