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Follicular helper T (TFH) cells are a specialized subset of CD4+ T cells that essentially support germinal center responses where high-affinity and long-lived humoral immunity is generated. The regulation of TFH cell survival remains unclear. Here we report that TFH cells show intensified lipid peroxidation and altered mitochondrial morphology, resembling the features of ferroptosis, a form of programmed cell death that is driven by iron-dependent accumulation of lipid peroxidation. Glutathione peroxidase 4 (GPX4) is the major lipid peroxidation scavenger and is necessary for TFH cell survival. The deletion of GPX4 in T cells selectively abrogated TFH cells and germinal center responses in immunized mice. Selenium supplementation enhanced GPX4 expression in T cells, increased TFH cell numbers and promoted antibody responses in immunized mice and young adults after influenza vaccination. Our findings reveal the central role of the selenium-GPX4-ferroptosis axis in regulating TFH homeostasis, which can be targeted to enhance TFH cell function in infection and following vaccination.
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Ferroptose/fisiologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Selênio/farmacologia , Células T Auxiliares Foliculares/fisiologia , Adolescente , Adulto , Animais , Sobrevivência Celular/imunologia , Criança , Feminino , Centro Germinativo/citologia , Centro Germinativo/imunologia , Homeostase/efeitos dos fármacos , Homeostase/genética , Humanos , Imunidade Humoral/imunologia , Vacinas contra Influenza/imunologia , Peroxidação de Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/fisiologia , Ovalbumina , Células T Auxiliares Foliculares/imunologia , Vacinação , Adulto JovemRESUMO
Odorants are detected as smell in the nasal epithelium of mammals by two G-protein-coupled receptor families, the odorant receptors and the trace amine-associated receptors1,2 (TAARs). TAARs emerged following the divergence of jawed and jawless fish, and comprise a large monophyletic family of receptors that recognize volatile amine odorants to elicit both intraspecific and interspecific innate behaviours such as attraction and aversion3-5. Here we report cryo-electron microscopy structures of mouse TAAR9 (mTAAR9) and mTAAR9-Gs or mTAAR9-Golf trimers in complex with ß-phenylethylamine, N,N-dimethylcyclohexylamine or spermidine. The mTAAR9 structures contain a deep and tight ligand-binding pocket decorated with a conserved D3.32W6.48Y7.43 motif, which is essential for amine odorant recognition. In the mTAAR9 structure, a unique disulfide bond connecting the N terminus to ECL2 is required for agonist-induced receptor activation. We identify key structural motifs of TAAR family members for detecting monoamines and polyamines and the shared sequence of different TAAR members that are responsible for recognition of the same odour chemical. We elucidate the molecular basis of mTAAR9 coupling to Gs and Golf by structural characterization and mutational analysis. Collectively, our results provide a structural basis for odorant detection, receptor activation and Golf coupling of an amine olfactory receptor.
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Aminas Biogênicas , Odorantes , Percepção Olfatória , Poliaminas , Receptores Odorantes , Animais , Camundongos , Aminas Biogênicas/análise , Aminas Biogênicas/química , Aminas Biogênicas/metabolismo , Microscopia Crioeletrônica , Subunidades alfa Gs de Proteínas de Ligação ao GTP/química , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/ultraestrutura , Odorantes/análise , Percepção Olfatória/fisiologia , Poliaminas/análise , Poliaminas/química , Poliaminas/metabolismo , Receptores de Amina Biogênica/química , Receptores de Amina Biogênica/genética , Receptores de Amina Biogênica/metabolismo , Receptores de Amina Biogênica/ultraestrutura , Receptores Odorantes/química , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Receptores Odorantes/ultraestrutura , Olfato/fisiologia , Espermidina/análise , Espermidina/química , Espermidina/metabolismoRESUMO
An interfacial solar steam generation evaporator for seawater desalination has attracted extensive interest in recent years. Nevertheless, challenges still remain in relatively low evaporation rate, unsatisfactory energy conversion efficiency, and salt accumulation. Herein, we have demonstrated a biomimetic bilayer composite aerogel consisting of bottom hydrophilic and vertically aligned EVOH channels and an upper hydrophobic conical Fe3O4 array. Thanks to the design merits, the 3D Fe3O4/V-EVOH evaporator exhibits a high evaporation rate of â¼2.446 kg m-2 h-1 and an impressive solar energy conversion efficiency of â¼165.5% under 1 sun illumination, which is superior to those of state-of-the-art evaporators reported so far. Moreover, the asymmetrical wettability not only allows the evaporator to self-float on the water but also facilitates the salt ion diffusion in the channels; thus, the evaporator shows no salt crystals on its surface and only a 6% decrease in evaporation performance even after the salt concentration increases from 0 to 10.0 wt %.
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High temperatures impair plant growth and reduce agricultural yields, but the underlying mechanisms remain elusive. The unicellular green alga Chlamydomonas reinhardtii is an excellent model to study heat responses in photosynthetic cells due to its fast growth rate, many similarities in cellular processes to land plants, simple and sequenced genome, and ample genetic and genomics resources. Chlamydomonas grows in light by photosynthesis and with externally supplied acetate as an organic carbon source. Understanding how organic carbon sources affect heat responses is important for the algal industry but remains understudied. We cultivated wild-type Chlamydomonas under highly controlled conditions in photobioreactors at 25 °C (control), 35 °C (moderate high temperature), or 40 °C (acute high temperature) with or without constant acetate supply for 1 or 4 day. Treatment at 35 °C increased algal growth with constant acetate supply but reduced algal growth without sufficient acetate. The overlooked and dynamic effects of 35 °C could be explained by induced acetate uptake and metabolism. Heat treatment at 40 °C for more than 2 day was lethal to algal cultures with or without constant acetate supply. Our findings provide insights to understand algal heat responses and help improve thermotolerance in photosynthetic cells.
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Chlamydomonas reinhardtii , Chlamydomonas , Chlamydomonas reinhardtii/metabolismo , Temperatura , Carbono/metabolismo , Fotossíntese , Acetatos/metabolismoRESUMO
An exciting result is reported in this study where a polypropylene (PP) foam with a high open-cell content was achieved by constructing a thermally conductive network for the first time. PP and nano-graphite particles were used as substrate and filler, respectively, to prepare the PP-graphite (PP-G) composite foam by twin-screw blending, hot pressing, and supercritical CO2 foaming. The nano-graphite particles can effectively adjust the microstructure of the PP-G foam and achieve a high porosity. When the amount of nano-graphite is 10.0 wt%, the PP-G foam exhibits optimal sound absorption performance, compression resistance, heat insulation, and hydrophobic properties. In the human-sensitive frequency range of 1000-6000 Hz, the corresponding average SAC is above 0.9, and the internal tortuosity is 5.27. After 50 cycles of compression, the compressive stress is 980 kPa and the SAC loss is only 7.8%. This study also innovatively proposed a new strategy to achieve the simple and rapid preparation of open-cell PP foams by increasing the thermal conductivity of the foaming substrate.
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PURPOSE: In recent years, the use of deep learning for medical image segmentation has become a popular trend, but its development also faces some challenges. Firstly, due to the specialized nature of medical data, precise annotation is time-consuming and labor-intensive. Training neural networks effectively with limited labeled data is a significant challenge in medical image analysis. Secondly, convolutional neural networks commonly used for medical image segmentation research often focus on local features in images. However, the recognition of complex anatomical structures or irregular lesions often requires the assistance of both local and global information, which has led to a bottleneck in its development. Addressing these two issues, in this paper, we propose a novel network architecture. METHODS: We integrate a shift window mechanism to learn more comprehensive semantic information and employ a semi-supervised learning strategy by incorporating a flexible amount of unlabeled data. Specifically, a typical U-shaped encoder-decoder structure is applied to obtain rich feature maps. Each encoder is designed as a dual-branch structure, containing Swin modules equipped with windows of different size to capture features of multiple scales. To effectively utilize unlabeled data, a level set function is introduced to establish consistency between the function regression and pixel classification. RESULTS: We conducted experiments on the COVID-19 CT dataset and DRIVE dataset and compared our approach with various semi-supervised and fully supervised learning models. On the COVID-19 CT dataset, we achieved a segmentation accuracy of up to 74.56%. Our segmentation accuracy on the DRIVE dataset was 79.79%. CONCLUSIONS: The results demonstrate the outstanding performance of our method on several commonly used evaluation metrics. The high segmentation accuracy of our model demonstrates that utilizing Swin modules with different window sizes can enhance the feature extraction capability of the model, and the level set function can enable semi-supervised models to more effectively utilize unlabeled data. This provides meaningful insights for the application of deep learning in medical image segmentation. Our code will be released once the manuscript is accepted for publication.
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BACKGROUND: Intensive care unit (ICU) delirium is a common complication in older critically ill patients that has a significant impact. The Family Confusion Assessment Method (FAM-CAM) is a vital tool for assisting family members in identifying delirium; however, no study has yet been reported on the Chinese version of the scale. OBJECTIVES: The objective of this study was to translate the FAM-CAM into a Chinese version and to verify its effectiveness for delirium detection in an online patient visit setting. METHODS: This was a cross-sectional study. The FAM-CAM was translated to Chinese according to the International Society for Pharmacoeconomics and Outcomes Research guidelines. Patients and family members were recruited to participate in delirium assessments in three ICUs of one hospital. Family members then used the Chinese version of the FAM-CAM to assess for delirium via online visitation, and ICU nurses assessed patients for delirium using the Intensive Care Delirium Screening Checklist (ICDSC). Results were then compared between family members' and nurses' assessments. RESULTS: Overall, 190 critically ill patients and 190 family members were included, of whom 117 (61.6%) were assessed for delirium using the Intensive Care Delirium Screening Checklist. The Cohen's kappa coefficient between the Intensive Care Delirium Screening Checklist and FAM-CAM was 0.759 (P < 0.01). The sensitivity of the Chinese version of the FAM-CAM was 0.880, specificity was 0.890, positive predictive value was 0.928, negative predictive value was 0.823, and area under the receiver operating characteristic curve was 0.881 (95% confidence interval: 0.872-0.935, P < 0.01). CONCLUSION: The Chinese version of the FAM-CAM was shown to effectively help families detect delirium and was suggested as a crucial tool for assisting ICU nurses in the early identification of delirium. This tool may effectively be used to assess delirium during online visits.
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Delírio , Unidades de Terapia Intensiva , Humanos , Delírio/diagnóstico , Masculino , Feminino , Estudos Transversais , Idoso , Pessoa de Meia-Idade , Família/psicologia , China , Traduções , Estado Terminal , Comparação Transcultural , InternetRESUMO
The incidence of urinary calculi in children has been increasing annually,and most of the cases are upper urinary tract stones.At present,surgery is the main way to treat upper urinary tract stones in children.With the gradual development of minimally invasive techniques in surgery,percutaneous nephrolithotomy,retrograde intrarenal surgery,and extracorporeal shock wave lithotripsy have become the main methods for treating upper urinary tract stones in children.We reviewed the current progress in surgical treatment of upper urinary tract stones in children and provided prospects for future treatment options.
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Nefrolitotomia Percutânea , Humanos , Criança , Nefrolitotomia Percutânea/métodos , Litotripsia/métodos , Cálculos Urinários/cirurgia , Cálculos Urinários/terapia , Cálculos Renais/cirurgiaRESUMO
In this study, a series of enantioenriched sp3-Ge/B bimetallic modules were successfully synthesized via an enantioselective copper-catalyzed hydroboration of carbagermatrane (Ge)-containing alkenes. Orthogonal cross-coupling selectivity under different Pd-catalyzed conditions was achieved in an enantiospecific manner. Notably, the chiral secondary Ge exhibited a remarkable transmetallation ability prior to primary or secondary Bpin. The effectiveness of this Ge/B bimetallic strategy was further demonstrated through the development of new functional small molecules with Aggregation-Induced Emission (AIE) and Circularly Polarized Luminescence (CPL) performance. This represents the first successful example of synthesis of enantioenriched alkylgermanium reagents that permit enantiospecific cross-coupling reactions.
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Obstructive sleep apnea (OSA), characterized by chronic intermittent hypoxia (CIH), is a common risk factor for pulmonary arterial hypertension (PAH). As a hypoxia-induced transcription factor, differentially expressed in chondrocytes (DEC1) negatively regulates the transcription of peroxisome proliferative activated receptor-γ (PPARγ), a recognized protective factor of PAH. However, whether and how DEC1 is associated with PAH pathogenesis remains unclear. In the present study, we found that DEC1 was increased in lungs and pulmonary arterial smooth muscle cells (PASMCs) of rat models of OSA-associated PAH. Oxidative indicators and inflammatory cytokines were also elevated in the blood of the rats. Similarly, hypoxia-treated PASMCs displayed enhanced DEC1 expression and reduced PPARγ expression in vitro. Functionally, DEC1 overexpression exacerbated reactive oxygen species (ROS) production and the expression of pro-inflammatory cytokines (such as TNFα, IL-1ß, IL-6, and MCP-1) in PASMCs. Conversely, shRNA knockdown of Dec1 increased PPARγ expression but attenuated hypoxia-induced oxidative stress and inflammatory responses in PASMCs. Additionally, DEC1 overexpression promoted PASMC proliferation, which was drastically attenuated by a PPARγ agonist rosiglitazone. Collectively, these results suggest that hypoxia-induced DEC1 inhibits PPARγ, and that this is a predominant mechanism underpinning oxidative stress and inflammatory responses in PASMCs during PAH. DEC1 could be used as a potential target to treat PAH.
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Hipertensão Arterial Pulmonar , Apneia Obstrutiva do Sono , Ratos , Animais , Hipertensão Arterial Pulmonar/induzido quimicamente , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/patologia , PPAR gama/genética , PPAR gama/metabolismo , Ratos Sprague-Dawley , Apoptose , Artéria Pulmonar/metabolismo , Estresse Oxidativo , Hipóxia/complicações , Hipóxia/genética , Hipóxia/metabolismo , Inflamação/metabolismo , Citocinas/genética , Citocinas/metabolismo , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/genética , Apneia Obstrutiva do Sono/metabolismo , Proliferação de Células/genética , Miócitos de Músculo Liso/metabolismoRESUMO
BACKGROUND: The floc is a characteristic of microbial aggregate growth, displaying cloudy suspensions in water. Floc formation has been demonstrated in a series of bacteria and the floc-forming bacteria play a crucial role in activated sludge (AS) process widely used for municipal sewage and industrial wastewater treatment over a century. It has been demonstrated that some exopolysaccharide biosynthesis genes and the sigma factor (sigma54 or rpoN) were required for floc forming in some bacteria. However, the mechanism underlying the floc formation stills need to be elucidated. RESULTS: In this study, we demonstrate that a TPR (Tetratricopeptide repeats) protein-encoding gene prsT is required for floc formation of Aquincola tertiaricarbonis RN12 and an upstream PEP-CTERM gene (designated pepA), regulated by RpoN1, is involved in its floc formation but not swarming motility and biofilm formation. Overexpression of PepA could rescue the floc-forming phenotype of the rpoN1 mutant by decreasing the released soluble exopolysaccharides and increasing the bound polymers. CONCLUSION: Our results indicate that the wide-spread PEP-CTERM proteins play an important role in the self-flocculation of bacterial cells and may be a component of extracellular polymeric substances required for floc-formation.
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Burkholderiales , Esgotos , Esgotos/microbiologia , Bactérias/genética , Proteínas , FloculaçãoRESUMO
Bisphenol A (BPA) exposure may be positively associated with cardiovascular disease (CVD). For more than a past decade, exposure to bisphenol F (BPF) and bisphenol S (BPS), as substitutes for BPA, has gradually increased in the population. Whether BPF and BPS exposure are associated with CVD remains unclear. We used data from the United States National Health and Nutrition Examination Survey (NHANES) from 2013 to 2016. A total of 3,502 participants, including 368 with CVD, were enrolled in the final analysis. Associations of BPA, BPF and BPS with CVD were determined using multivariate logistic regression analysis. The highest level of urinary BPA (≥2.5 ng/ml) was significantly associated with a higher CVD prevalence (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.08-2.3) among all participants in the quartile analysis. In stratified analyses, the highest level of urinary BPA was positively associated with CVD prevalence in males (1.86, 1.1-3.13) and the elderly population (≥60 years old) (1.89, 1.2-2.97). Higher levels of urinary BPF were positively associated with CVD prevalence in females (Q2: 1.81, 1.03-3.18; Q4: 1.73, 1.07-2.79) and in the elderly population (Q3: 1.7, 1.16-2.48). No associations were found between urinary BPS levels and CVD, regardless of whether the participants were stratified by age or sex. In conclusion, exposure to BPA or BPF was positively correlated with CVD prevalence, but an association was not found for exposure to BPS. BPF may not be as safe as assumed for human health.
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Doenças Cardiovasculares , Masculino , Feminino , Humanos , Adulto , Idoso , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Inquéritos Nutricionais , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Compostos Benzidrílicos/toxicidadeRESUMO
In view of the difficulties regarding that airborne navigation equipment relies on imports and the expensive domestic high-precision navigation equipment in the manufacturing field of Chinese navigable aircraft, a dual-antenna GNSS (global navigation satellite system)/MINS (micro-inertial navigation system) integrated navigation system was developed to implement high-precision and high-reliability airborne integrated navigation equipment. First, the state equation and measurement equation of the system were established based on the classical discrete Kalman filter principle. Second, according to the characteristics of the MEMS (micro-electric-mechanical system), the IMU (inertial measurement unit) is not sensitive to Earth rotation to realize self-alignment; the magnetometer, accelerometer and dual-antenna GNSS are utilized for reliable attitude initial alignment. Finally, flight status identification was implemented by the different satellite data, accelerometer and gyroscope parameters of the aircraft in different states. The test results shown that the RMS (root mean square) of the pitch angle and roll angle error of the testing system are less than 0.05° and the heading angle error RMS is less than 0.15° under the indoor static condition. A UAV flight test was carried out to test the navigation effect of the equipment upon aircraft take-off, climbing, turning, cruising and other states, and to verify the effectiveness of the system algorithm.
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OBJECTIVE: The present study aimed to determine whether peripheral blood neural cell adhesion molecule (NCAM)/amphiphysin 1 dual-labeled exosomal proteins and microRNAs (miRs) might serve as a marker for the early diagnosis of Alzheimer's disease (AD). METHODS: This observational, retrospective, multicenter study used a two-stage design conducted in Beijing and Shanghai, China. The subjects included 76 patients with subjective cognitive decline (SCD), 80 with amnestic mild cognitive impairment (aMCI), 76 with dementia of Alzheimer's type (AD), 40 with vascular dementia (VaD), and 40 controls in the discovery stage. These results were confirmed in the verification stage. The levels of Aß42, Aß42/40, T-Tau, P-T181-tau, neurofilament light chain (NfL), and miR-29c-3p in peripheral blood amphiphysin 1 single-labeled and NCAM/amphiphysin 1 dual-labeled exosomes were captured and detected by immunoassay. RESULTS: In the discovery stage, the levels of Aß42 and miR-29c-3p in peripheral blood NCAM/amphiphysin 1 dual-labeled exosome of the SCD group were significantly higher than those in control and VaD groups (all P < 0.05). The verification stage further confirmed the results of the discovery stage. Plasma NCAM/amphiphysin 1 dual-labeled exosomal miR-29c-3p showed a good diagnostic performance. The NCAM/amphiphysin 1 dual-labeled exosomal miR-29c-3p had the highest AUC for diagnosis of SCD. The levels of Aß42, Aß42/40, Tau, P-T181-tau, and miR-29c-3p in peripheral blood exosomes were correlated to those in CSF (all P < 0.05). The combination of exosomal biomarkers had slightly higher diagnostic efficiency than the individual biomarkers and that the exosomal biomarkers had the same diagnostic power as the CSF biomarkers. CONCLUSION: The plasma NCAM/amphiphysin 1 dual-labeled exosomal miR-29c-3p had potential advantages in the diagnosis of SCD.
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Doença de Alzheimer , Disfunção Cognitiva , Demência Vascular , Exossomos , MicroRNAs , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Biomarcadores/metabolismo , China , Disfunção Cognitiva/metabolismo , Demência Vascular/metabolismo , Exossomos/metabolismo , Humanos , MicroRNAs/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Estudos RetrospectivosRESUMO
Adoptive transfer of T cell receptor (TCR)-engineered T cells targeting viral epitopes represents a promising approach for treating virus-related cancers. However, the efficient identification of epitopes for T cells and the corresponding TCR remains challenging. Here, we report a workflow permitting the rapid generation of human papillomavirus (HPV)-specific TCR-T cells. Six epitopes of viral proteins belonged to HPV16 or HPV18 were predicted to have high affinity to A11:01 according to bioinformatic analysis. Subsequently, CTL induction were performed with these six antigen peptides separately, and antigen-specific T cells were sorted by FACS. TCR clonotypes of these virus-specific T cells were determined using next-generation sequencing. To improve the efficiency of TCRαß pair validation, a lentiviral vector library containing 116 TCR constructs was generated that consisted of predominant TCRs according to TCR repertoire analysis. Later, TCR library transduced T cells were simulated with peptide pool-pulsed antigen-presenting cells, then CD137-positive cells were sorted and subjected to TCR repertoire analysis. The top-hit TCRs and corresponding antigen peptides were deduced and validated. Through this workflow, a TCR targeting the E692-101 of HPV16 was identified. These HPV16-specific TCR-T cells showed high activity towards HPV16-positive human cervical cancer cells in vitro and efficiently repressed tumor growth in a murine model. This study provides a HPV16-specific TCR fitted to the HLA-A11:01 population, and exemplifies an efficient approach that can be applied in large-scale screening of virus-specific TCRs, further encouraging researchers to exploit the therapeutic potential of the TCR-T cell technique in treating virus-related cancers.
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Linfócitos T , Neoplasias do Colo do Útero , Feminino , Humanos , Camundongos , Animais , Receptores de Antígenos de Linfócitos T , Papillomavirus Humano 16 , Neoplasias do Colo do Útero/terapia , Peptídeos , EpitoposRESUMO
Photonic crystal lasers with a high-Q factor and small mode volume are ideal light sources for on-chip nano-photonic integration. Due to the submicron size of their active region, it is usually difficult to achieve high output power and single-mode lasing at the same time. In this work, we demonstrate well-selected single-mode lasing in a line-defect photonic crystal cavity by coupling it to the high-Q modes of a short double-heterostructure photonic crystal cavity. One of the FP-like modes of the line-defect cavity can be selected to lase by thermo-optically tuning the high-Q mode of the short cavity into resonance. Six FP-like modes are successively tuned into lasing with side mode suppression ratios all exceeding 15 dB. Furthermore, we show a continuous wavelength tunability of about 10 nm from all the selected modes. The coupled cavity system provides a remarkable platform to explore the rich laser physics through the spatial modulation of vacuum electromagnetic field at submicron scale.
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BACKGROUND: Acute kidney injury (AKI) is a public health problem with no specific therapies in the clinic and the underlying pathogenesis of AKI remains obscure. Bombesin receptor-activated protein (BRAP, C6ORF89 protein) was initially discovered as a ligand for a previously orphan G-protein-coupled receptor bombesin-like receptor-3. At present, accepted biological effects of BRAP include cell cycle progression, wound repair and the activation of histone deacetylases. However, its role in kidney disease is unknown. In this study we have investigated the role of BRAP and underlying mechanisms involved in cisplatin (CP)-induced AKI. METHODS: Here we used Bc004004 (homologous of C6ORF89 in mice) knockout mice and HK2 cells to investigate the effect of BRAP on AKI in vitro and in vivo. We analyzed ChIP-Seq and RNA-Seq data to search for the upstream regulators of BRAP and downstream mediators of BRAP action in AKI. Immunostaining, real-time polymerase chain reaction (PCR), co-immunoprecipitation, a dual-luciferase reporter assay and ChIP-PCR assay were applied to reveal the upstream and downstream regulation mechanism of BRAP during cisplatin-induced AKI. RESULTS: BRAP was downregulated in mice and human kidneys with AKI. Global Bc004004 deletion alleviated tubular cell apoptosis and necroptosis in CP-induced AKI mice, whereas local overexpression of BRAP in kidneys aggravated them. Pan-caspase inhibitor Z-VAD pretreatment attenuated CP-induced blood creatinine increase and kidney injury in wild-type mice but not in BRAP -/- mice. The activation of mixed lineage kinase like-domain was magnified by Z-VAD in CP-treated mice, especially in BRAP -/- mice. The cytoprotective effect of Z-VAD was more substantial than necrostatin-1 (Nec-1, an inhibitor of necroptosis) in CP-treated human kidney proximal tubular epithelial (HK2) cells. Furthermore, Nec-1 pretreatment reduced the CP-induced cell death in BRAP overexpression HK2 cells but did not work in cells with normal BRAP levels. We determined that CP treatment activated the nuclear factor-κB subunit P65 and inhibition of P65 increased the messenger RNA (mRNA) levels of BRAP in HK2 cells. The chromatin immunoprecipitation assay and dual-luciferase reporter gene assay verified P65 binding to the C6ORF89 promoter and reduced its mRNA expression upon CP treatment. Next we found that sirtuin 2 (SIRT2) was downregulated in CP-induced AKI and BRAP levels directly impacted the protein levels of SIRT2. Our findings further confirmed that BRAP regulates the SIRT2 protein levels by affecting SIRT2's interactions with E3 ubiquitin ligase HRD1 and subsequent proteasomal degradation. CONCLUSIONS: Our results demonstrated that BRAP played an important role in tubular cell apoptosis and necroptosis during CP-induced AKI. Safe and efficient BRAP inhibitors might be effective therapeutic options for AKI.
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Injúria Renal Aguda , Cisplatino , Animais , Humanos , Camundongos , Injúria Renal Aguda/patologia , Apoptose , Bombesina/efeitos adversos , Cisplatino/toxicidade , Camundongos Endogâmicos C57BL , Receptores da Bombesina , RNA Mensageiro , Sirtuína 2RESUMO
Constructing a sterile membrane with a robust and antifouling surface is a powerful means to improve the sterile filtration efficiency of sterile membranes. In this work, a robust EVOH nanofibrous sterile membrane was facilely fabricated by the method of in situ crosslinking with glutaraldehyde and surface plasma treatment. The resultant EVOH nanofibrous sterile membrane possessed a carboxylated-crosslinked surface, with high hydrophilicity, which generated high chemical stability, high-temperature steam resistance, and an ultrahigh antifouling performance against bovine serum albumin, ribonucleic acid and nanoparticle pollutants. Moreover, the membrane also exhibited a reasonably high primary water permeance (4522.2 LMH bar-1 at 0.2 MPa), as well as an absolute interception rate (100%) of Escherichia coli, Staphylococcus aureus cells and Brevundimonas diminuta superior to the state-of-the-art sterile membrane. Moreover, the modified membrane packed syringe-driven filter presented 100% interception (LRV ≥ 7) to Brevundimonas diminuta and high permeation flux (from 10.8 to 41.8 L·h-1) in a wide operating pressure range of 0.1 MPa to 0.6 MPa, indicating its potential in real bio-separation applications. This work provides a facile strategy for the preparation of a high-performance sterile membrane for biological drug product sterilization.