RESUMO
Immunotherapy can potentially suppress the highly aggressive glioblastoma (GBM) by promoting T lymphocyte infiltration. Nevertheless, the immune privilege phenomenon, coupled with the generally low immunogenicity of vaccines, frequently hampers the presence of lymphocytes within brain tumors, particularly in brain tumors. In this study, the membrane-disrupted polymer-wrapped CuS nanoflakes that can penetrate delivery to deep brain tumors via releasing the cell-cell interactions, facilitating the near-infrared II (NIR II) photothermal therapy, and detaining dendritic cells for a self-cascading immunotherapy are developed. By convection-enhanced delivery, membrane-disrupted amphiphilic polymer micelles (poly(methoxypoly(ethylene glycol)-benzoic imine-octadecane, mPEG-b-C18) with CuS nanoflakes enhances tumor permeability and resides in deep brain tumors. Under low-power NIR II irradiation (0.8 W/cm2), the intense heat generated by well-distributed CuS nanoflakes actuates the thermolytic efficacy, facilitating cell apoptosis and the subsequent antigen release. Then, the positively charged polymer after hydrolysis of the benzoic-imine bond serves as an antigen depot, detaining autologous tumor-associated antigens and presenting them to dendritic cells, ensuring sustained immune stimulation. This self-cascading penetrative immunotherapy amplifies the immune response to postoperative brain tumors but also enhances survival outcomes through effective brain immunotherapy.
Assuntos
Neoplasias Encefálicas , Membrana Celular , Células Dendríticas , Imunoterapia , Raios Infravermelhos , Células Dendríticas/imunologia , Células Dendríticas/efeitos dos fármacos , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Animais , Camundongos , Humanos , Membrana Celular/química , Linhagem Celular Tumoral , Micelas , Nanopartículas/química , Terapia Fototérmica , Polietilenoglicóis/química , Glioblastoma/terapia , Glioblastoma/imunologia , Glioblastoma/patologia , Apoptose/efeitos dos fármacosRESUMO
Leveraging endogenous tumor-resident T-cells for immunotherapy using bispecific antibodies (BsAb) targeting CD20 and CD3 has emerged as a promising therapeutic strategy for patients with B-cell non-Hodgkin lymphomas. However, features associated with treatment response or resistance are unknown. To this end, we analyzed data from patients treated with epcoritamab-containing regimens in the EPCORE NHL-2 trial (NCT04663347). We observed downregulation of CD20 expression on B-cells following treatment initiation both in progressing patients and in patients achieving durable complete responses (CR), suggesting that CD20 downregulation does not universally predict resistance to BsAb-based therapy. Single-cell immune profiling of tumor biopsies obtained following one cycle of therapy revealed substantial clonal expansion of cytotoxic CD4+ and CD8+ T-cells in patients achieving CR, and an expansion of follicular helper and regulatory CD4+ T-cells in patients whose disease progressed. These results identify distinct tumor-resident T-cell profiles associated with response or resistance to BsAb therapy.
RESUMO
BACKGROUND: Cerebral examination via CTA is always the first choice for patients with unexpected brain injury or different types of brain lesions to detect ruptured hemangiomas, vascular infarcts, or other brain tissue lesions. OBJECTIVE: This study innovated the acrylic gauge with five eccentric circles for computed tomography angiography (CTA) analysis to optimize the spatial resolution via Taguchi's methodology. METHODS: The customized gauge was revised from the V-shaped slit gauge and transferred into five eccentric circles' slit gauge. The gauge was assembled with another six acrylic layers to simulate the human head. Taguchi's L18 orthogonal array was adopted to optimize the spatial resolution of CTA imaging quality. In doing so, six essential factors of CTA are kVp, mAs, spiral rotation pitch, FOV, rotation time of the CT and reconstruction filter, and each factor has either two or three levels to organize into eighteen combinations to simulate the full factor combination of 486 (21 × 35 = 486) times according to Taguchi's recommendation. Three well-trained radiologists ranked the gauge's 18 CTA scanned imaging qualities according to contrast, sharpness, and spatial resolution and derived the unique fish-bone-plot of six factors for further analysis. The optimal factor combination of CTA was proven by follow-up verification and ANOVA to obtain this study's dominant or minor factor. RESULTS: The optimal factor combination of CTA was A2 (120 kVp), B3 (200 mAs), C1 (Pitch 0.6), D2 (FOV 220 mm2), E1 (rotation time 0.33 s), and F3 (Brain sharp, UC). Furthermore, deriving a quantified MDD (minimum detectable difference) to imply the spatial resolution of CTA, a semiauto profile analysis program run in MATLAB and OriginPro was recommended to evaluate the MDD and to suppress the manual error in calculation. Eventually, the derived MDDs of the conventional and optimal factor combinations of CTA were 2.35 and 2.26 mm, respectively, in this study. CONCLUSION: Taguchi's methodology was found applicable for quantifying the CTA imaging quality in practical applications.
Assuntos
Angiografia por Tomografia Computadorizada , Humanos , Angiografia por Tomografia Computadorizada/métodos , Imagens de FantasmasRESUMO
BACKGROUND: The available evidence regarding the predictive value of troponins and natriuretic peptides for early postoperative outcomes in pediatrics is limited, controversial, and based on small sample sizes. The authors aimed to investigate the association of N-terminal pro B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hs-TnT) with the in-hospital adverse outcomes after congenital cardiac surgeries. METHODS: A secondary analysis based on a prospective study of pediatric congenital heart disease (CHD) patients was conducted to investigate the association of NT-proBNP and hs-TnT tested within 6 h postoperatively with in-hospital adverse events. A multivariate logistic regression analysis with a minimum P value approach was used to identify the optimal thresholds of NT-proBNP and hs-TnT for risk stratification. RESULTS: NT-proBNP and hs-TnT are positively correlated with cardiopulmonary bypass time, mechanical ventilation duration, and pediatric intensive care unit stay. The predictive performance of NT-proBNP is excellent for adverse events in both patients younger than 1 year [area under the curve (AUC): 0.771, 0.693-0.850] and those older than 1 year (AUC: 0.839, 0.757-0.922). However, hs-TnT exhibited a satisfactory predictive value solely in patients aged over 1 year. (AUC: 0.784, 0.717-0.852). NT-proBNP levels of 2000-10 000 ng/l [odds ratio (OR): 3.79, 1.47-9.76] and exceeding 10 000 ng/l (OR: 12.21, 3.66-40.80) were associated with a higher risk of postoperative adverse events in patients younger than 1 year. Patients older than 1 year, with NT-proBNP higher than 500 ng/l (OR: 15.09, 6.05-37.66) or hs-TnT higher than 1200 ng/l (OR: 5.50, 1.47-20.59), had a higher incidence of postoperative adverse events. CONCLUSIONS: NT-proBNP and hs-TnT tested within postoperative 6 h demonstrated significant predictive value for postoperative adverse events in CHD patients older than 1 year. However, among CHD patients younger than 1 year, only NT-proBNP exhibited commendable predictive performance for postoperative adverse events.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Valor Preditivo dos Testes , Troponina T , Humanos , Peptídeo Natriurético Encefálico/sangue , Feminino , Masculino , Fragmentos de Peptídeos/sangue , Cardiopatias Congênitas/cirurgia , Cardiopatias Congênitas/sangue , Lactente , Troponina T/sangue , Estudos Prospectivos , Pré-Escolar , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Biomarcadores/sangue , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/diagnóstico , Criança , Recém-NascidoRESUMO
Combination immunotherapy has emerged as a promising strategy to address the challenges associated with immune checkpoint inhibitor (ICI) therapy in breast cancer. The efficacy of combination immunotherapy hinges upon the intricate and dynamic nature of the tumor microenvironment (TME), characterized by cellular heterogeneity and molecular gradients. However, current methodologies for drug screening often fail to accurately replicate these complex conditions, resulting in limited predictive capacity for treatment outcomes. Here, a tumor-microenvironment-on-chip (TMoC), integrating a circulation system and ex vivo tissue culture with physiological oxygen and nutrient gradients, is described. This platform enables spatial infiltration of cytotoxic CD8+ T cells and their targeted attack on the tumor, while preserving the high complexity and heterogeneity of the TME. The TMoC is employed to assess the synergistic effect of five targeted therapy drugs and five chemotherapy drugs in combination with immunotherapy, demonstrating strong concordance between chip and animal model responses. The TMoC holds significant potential for advancing drug development and guiding clinical decision-making, as it offers valuable insights into the complex dynamics of the TME.
Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Animais , Microambiente Tumoral , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Resultado do TratamentoRESUMO
Selective autophagy is a defense mechanism by which foreign pathogens and abnormal substances are processed to maintain cellular homeostasis. Sequestosome 1 (SQSTM1)/p62, a vital selective autophagy receptor, recruits ubiquitinated cargo to form autophagosomes for lysosomal degradation. Nab-PTX is an albumin-bound paclitaxel nanoparticle used in clinical cancer therapy. However, the role of SQSTM1 in regulating the delivery and efficacy of nanodrugs remains unclear. Here we showed that SQSTM1 plays a crucial role in Nab-PTX drug delivery and efficacy in human lung and colorectal cancers. Nab-PTX induces SQSTM1 phosphorylation at Ser403, which facilitates its incorporation into the selective autophagy of nanoparticles, known as nanoparticulophagy. Nab-PTX increased LC3-II protein expression, which triggered autophagosome formation. SQSTM1 enhanced Nab-PTX recognition to form autophagosomes, which were delivered to lysosomes for albumin degradation, thereby releasing PTX to induce mitotic catastrophe and apoptosis. Knockout of SQSTM1 downregulated Nab-PTX-induced mitotic catastrophe, apoptosis, and tumor inhibition in vitro and in vivo and inhibited Nab-PTX-induced caspase 3 activation via a p53-independent pathway. Ectopic expression of SQSTM1 by transfection of an SQSTM1-GFP vector restored the drug efficacy of Nab-PTX. Importantly, SQSTM1 is highly expressed in advanced lung and colorectal tumors and is associated with poor overall survival in clinical patients. Targeting SQSTM1 may provide an important strategy to improve nanodrug efficacy in clinical cancer therapy. This study demonstrates the enhanced efficacy of Nab-PTX for human lung and colorectal cancers via SQSTM1-mediated nanodrug delivery.
RESUMO
Healing of large calvarial bone defects in adults is challenging. We previously showed that inducing chondrogenic differentiation of mesenchymal stem cells from bone marrow (BMSC) or adipose tissue (ASC) before implantation can switch the repair pathway and improve calvarial bone healing. Split dCas12a activator is a new CRISPR activation system comprising the amino (N) and carboxyl (C) fragments of dCas12a protein, each being fused with synthetic transcription activators at both termini. The split dCas12a activator was shown to induce programmable gene expression in cell lines. Here we exploited the split dCas12a activator to activate the expression of chondroinductive long non-coding RNA H19. We showed that co-expression of the split N- and C-fragments resulted in spontaneous dimerization, which elicited stronger activation of H19 than full-length dCas12a activator in rat BMSC and ASC. We further packaged the entire split dCas12a activator system (13.2 kb) into a hybrid baculovirus vector, which enhanced and prolonged H19 activation for at least 14 days in BMSC and ASC. The extended H19 activation elicited potent chondrogenic differentiation and inhibited adipogenesis. Consequently, the engineered BMSC promoted in vitro cartilage formation and augmented calvarial bone healing in rats. These data implicated the potentials of the split dCas12a activator for stem cell engineering and regenerative medicine.
Assuntos
Células-Tronco Mesenquimais , RNA Longo não Codificante , Animais , Ratos , Tecido Adiposo , Diferenciação Celular/genética , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , RNA Longo não Codificante/genéticaRESUMO
Hexanucleotide repeat expansions in C9ORF72 are the most common genetic cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Studies have shown that the hexanucleotide expansions cause the noncanonical translation of C9ORF72 transcripts into neurotoxic dipeptide repeat proteins (DPRs) that contribute to neurodegeneration. We show that a cell-penetrant peptide blocked the nuclear export of C9ORF72-repeat transcripts in HEK293T cells by competing with the interaction between SR-rich splicing factor 1 (SRSF1) and nuclear export factor 1 (NXF1). The cell-penetrant peptide also blocked the translation of toxic DPRs in neurons differentiated from induced neural progenitor cells (iNPCs), which were derived from individuals carrying C9ORF72-linked ALS mutations. This peptide also increased survival of iNPC-differentiated C9ORF72-ALS motor neurons cocultured with astrocytes. Oral administration of the cell-penetrant peptide reduced DPR translation and rescued locomotor deficits in a Drosophila model of mutant C9ORF72-mediated ALS/FTD. Intrathecal injection of this peptide into the brains of ALS/FTD mice carrying a C9ORF72 mutation resulted in reduced expression of DPRs in mouse brains. These findings demonstrate that disrupting the production of DPRs in cellular and animal models of ALS/FTD might be a strategy to ameliorate neurodegeneration in these diseases.
Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Humanos , Animais , Camundongos , Dipeptídeos , Proteína C9orf72 , Transporte Ativo do Núcleo Celular , Células HEK293 , Peptídeos , Neurônios Motores , RNA , Fatores de Processamento de Serina-ArgininaRESUMO
Guided bone regeneration surgery is an important dental operation used to regenerate enough bone to successfully heal dental implants. When this technique is performed on maxilla sinuses, hyaluronic acid (HLA) can be used as an auxiliary material to improve the graft material handling properties. Recent studies have indicated that low-molecular hyaluronic acid (L-HLA) provides a better regeneration ability than high-molecular-weight (H-HLA) analogues. The aim of this study was to fabricate an L-HLA-carboxymethyl cellulose (CMC) hybrid to promote bone regeneration while maintaining viscosity. The proliferation effect of fabricated L-HLA was tested using dental pulp stem cells (DPSCs). The mitogen-activated protein kinase (MAPK) pathway was examined using cells cultured with L-HLA combined with extracellular-signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 inhibitors. The bone growth promotion of fabricated L-HLA/CMC hybrids was tested using an animal model. Micro-computer tomography (Micro-CT) and histological images were evaluated quantitatively to compare the differences in the osteogenesis between the H-HLA and L-HLA. Our results show that the fabricated L-HLA can bind to CD44 on the DPSC cell membranes and affect MAPK pathways, resulting in a prompt proliferation rate increase. Micro CT images show that new bone formation in rabbit calvaria defects treated with L-HLA/CMC was almost two times higher than in defects filled with H-HLA/CMC (p < 0.05) at 4 weeks, a trend that remained at 8 weeks and was confirmed by HE-stained images. According to these findings, it is reasonable to conclude that L-HLA provides better bone healing than H-HLA, and that the L-HLA/CMC fabricated in this study is a potential candidate for improving bone healing efficiency when a guided bone regeneration surgery was performed.
RESUMO
How immune dysregulation affects recovery from COVID-19 infection in patients with cancer remains unclear. We analyzed cellular and humoral immune responses in 103 patients with prior COVID-19 infection, more than 20% of whom had delayed viral clearance. Delayed clearance was associated with loss of antibodies to nucleocapsid and spike proteins with a compensatory increase in functional T cell responses. High-dimensional analysis of peripheral blood samples demonstrated increased CD8+ effector T cell differentiation and a broad but poorly converged COVID-specific T cell receptor (TCR) repertoire in patients with prolonged disease. Conversely, patients with a CD4+ dominant immunophenotype had a lower incidence of prolonged disease and exhibited a deep and highly select COVID-associated TCR repertoire, consistent with effective viral clearance and development of T cell memory. These results highlight the importance of B cells and CD4+ T cells in promoting durable SARS-CoV-2 clearance and the significance of coordinated cellular and humoral immunity for long-term disease control.
Assuntos
COVID-19 , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Humanos , Imunidade Celular , Imunidade Humoral , Memória Imunológica , Receptores de Antígenos de Linfócitos T , SARS-CoV-2RESUMO
T lymphocyte infiltration with immunotherapy potentially suppresses most devastating brain tumors. However, local immune privilege and tumor heterogeneity usually limit the penetration of immune cells and therapeutic agents into brain tumors, leading to tumor recurrence after treatment. Here, a rabies virus glycoprotein (RVG)-camouflaged gold yarnball (RVG@GY) that can boost the targeting efficiency at a brain tumor via dual hierarchy- and RVG-mediated spinal cord transportation, facilitating the decrease of tumor heterogeneity for T cell infiltration, is developed. Upon magnetoelectric irradiation, the electron current generated on the GYs activates the electrolytic penetration of palbociclib-loaded dendrimer (Den[Pb]) deep into tumors. In addition, the high-density GYs at brain tumors also induces the disruption of cell-cell interactions and T cell infiltration. The integration of the electrolytic effects and T cell infiltration promoted by drug-loaded RVG@GYs deep in the brain tumor elicits sufficient T cell numbers and effectively prolongs the survival rate of mice with orthotopic brain tumors.
Assuntos
Neoplasias Encefálicas , Vírus da Raiva , Animais , Neoplasias Encefálicas/tratamento farmacológico , Glicoproteínas , Ouro/uso terapêutico , Camundongos , Linfócitos T/patologiaAssuntos
Colite , Transtornos Parkinsonianos , Animais , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Camundongos , Transtornos Parkinsonianos/genética , Transtornos Parkinsonianos/metabolismo , Fator de Necrose Tumoral alfa/genéticaRESUMO
BACKGROUND: Leucine-rich repeat kinase 2 (LRRK2) is a common risk gene for Parkinson's disease (PD) and inflammatory bowel disorders. However, the penetrance of the most prevalent LRRK2 mutation, G2019S, is <50%. Factors other than genetic mutations are needed in PD process. OBJECTIVES: To examine whether and how gut inflammation may act as an environmental trigger to neurodegeneration in PD. METHODS: A mild and chronic dextran sodium sulfate (DSS)-induced colitis mice model harboring LRRK2 G2019S mutation was established. The colitis severity, immune responses, locomotor function, dopaminergic neuron, and microglia integrity were compared between littermate controls, transgenic LRRK2 wild type (WT), and LRRK2 G2019S mice. RESULTS: The LRRK2 G2019S mice are more vulnerable to DSS-induced colitis than littermate controls or LRRK2 WT animals with increased intestinal expressions of pattern-recognition receptors, including toll-like receptors (TLRs), nuclear factor (NF)-κB activation, and pro-inflammatory cytokines secretion, especially tumor necrosis factor (TNF)-α. Notably, the colonic expression of α-synuclein was significantly increased in LRRK2 G2019S colitis mice. We subsequently observed more aggravated locomotor defect, microglia activation, and dopaminergic neuron loss in LRRK2 G2019S colitis mice than control animals. Treatment with anti-TNF-α monoclonal antibody, adalimumab, abrogated both gut and neuroinflammation, mitigated neurodegeneration, and improved locomotor function in LRRK2 G2019S colitis mice. Finally, we validated increased colonic expressions of LRRK2, TLRs, and NF-κB pathway proteins and elevated plasma TNF-α level in PD patients compared to controls, especially in those with LRRK2 risk variants. CONCLUSIONS: Our findings demonstrate that chronic colitis promotes parkinsonism in genetically susceptible mice and TNF-α plays a detrimental role in the gut-brain axis of PD. © 2021 International Parkinson and Movement Disorder Society.
Assuntos
Colite , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Doença de Parkinson , Transtornos Parkinsonianos , Animais , Animais Geneticamente Modificados , Colite/induzido quimicamente , Colite/complicações , Colite/genética , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Camundongos , Camundongos Transgênicos , Mutação/genética , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Transtornos Parkinsonianos/genética , Inibidores do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfaRESUMO
A five-compartmental biokinetic model of I-131 radioiodine based on in-vivo gamma camera scanning results was developed and successfully applied to nine thyroid cancer patients who were administered 1,110 MBq I-131 in capsules for the residual thyroid gland ablation. The I-131 solution activity among internal organs was analyzed via the revised biokinetic model of iodine recommended by the ICRP-30 and -56 reports. Accordingly, a five-compartmental (stomach, body fluid, thyroid, whole body, and excretion) model was established to simulate the metabolic mechanism of I-131 in thyroid cancer patients, whereas the respective four simultaneous differential equations were solved via a self-developed program run in MATLAB. This made it possible to provide a close correlation between MATLAB simulation results and empirical data. The latter data were collected through in-vivo gamma camera scans of nine patients obtained after 1, 4, 24, 48, 72, and 168 hours after radioactive I-131 administration. The average biological half-life values for the stomach, body fluid, thyroid, and whole body of thyroid cancer patients under study were 0.54±0.32, 12.6±1.8, 42.8±5.1, and 12.6±1.8 h, respectively. The corresponding branching ratios I12, I23, I25, I34, I42, and I45 as denoted in the biokinetic model of iodine were 1.0, 0.21±0.14, 0.79±0.14, 1.0, 0.1, and 0.9, respectively. The average values of the AT dimensionless index used to verify the agreement between empirical and numerical simulation results were 0.056±0.017, 0.017±0.014, 0.044±0.023, and 0.045±0.009 for the stomach, thyroid, body fluid + whole body, and total, respectively. The results obtained were considered quite instrumental in the elucidation of metabolic mechanisms in the human body, particularly in thyroid cancer patients.
Assuntos
Radioisótopos do Iodo/farmacocinética , Modelos Biológicos , Compostos Radiofarmacêuticos/farmacocinética , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/metabolismo , Adulto , Idoso , Simulação por Computador , Feminino , Câmaras gama , Meia-Vida , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Distribuição TecidualRESUMO
To explore the regulatory factor of light quality affecting exopolysaccharide (EPS) production, transcriptome analysis of Nostoc flagelliforme cells exposed to red light (R), blue light (B), and mixed light (B/R = 15:7) (BR) with white fluorescent light as control was performed. The differentially expressed genes mainly enriched in carbohydrate metabolism and energy metabolism. Significant enrichment in the oxidation-reduction process and energy metabolism indicated that intracellular redox homeostasis was disrupted. An assay of reactive oxygen species (ROS) and malondialdehyde contents demonstrated light quality induced oxidative stress. To illustrate the relationship between ROS level and EPS accumulation, the effects of the exogenous addition of ROS scavenger N-acetyl cysteine and inducer H2O2 on the oxidation-reduction level and EPS production were compared. The results revealed that light quality regulated EPS biosynthesis via the intracellular ROS level directly other than oxidative stress. Understanding such relationships might provide guidance for efficient EPS production to regulate the intracellular redox level.
Assuntos
Nostoc/metabolismo , Polissacarídeos Bacterianos/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Meios de Cultura/metabolismo , Peróxido de Hidrogênio/metabolismo , Luz , Nostoc/genética , Nostoc/crescimento & desenvolvimento , Nostoc/efeitos da radiação , Oxirredução , Estresse Oxidativo/efeitos da radiaçãoRESUMO
Nostoc flagelliforme is a pioneer organism in the desert and highly resistant to ultraviolet B (UV-B) radiation, while the involved adaptive mechanism has not been fully explored yet. To elucidate the responsive mechanism, two doses of UV-B radiation (low: 1 W/m2 and high: 5 W/m2) were irradiated for 6 h and 48 h, respectively, and their effects on global metabolism in N. flagelliforme were comprehensively investigated. In this study, we used iTRAQ-based proteomic approach to explore the proteomes of N. flagelliforme, and 151, 172, 124 and 148 differentially expressed proteins were identified under low and high UV-B doses for 6 h and 48 h, respectively. Functional classification analysis showed these proteins were mainly involved in photosynthesis, amino acid metabolism, antioxidant activity and carbohydrate metabolism. Further analysis revealed that UV-B imposed restrictions on primary metabolism including photosynthesis, Calvin cycle, and amino acid metabolism, and cells started defense mechanism through repair of DNA and protein damage, increasing antioxidant activity, and accumulating extracellular polysaccharides to minimize the damage. Moreover, high UV-B dose imposed more severe restrictions and activated stronger defense mechanism compared with low dose. The results would improve the understanding of molecular mechanisms of UV-B-stress adaption in N. flagelliforme.
Assuntos
Nostoc/metabolismo , Nostoc/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Adaptação Biológica/genética , Aminoácidos/metabolismo , Antioxidantes/metabolismo , Metabolismo dos Carboidratos , Fotossíntese , Proteoma/metabolismo , Proteômica/métodosRESUMO
Nostoc flagelliforme is a pioneer organism in the desert and exerts important ecological functions. The habitats of N. flagelliforme are characterized by intense solar radiation, while the ultraviolet B (UV-B) tolerance has not been fully explored yet. To evaluate the physiological responses of N. flagelliforme to UV-B radiation, three intensities (1 W m-2, 3 W m-2 and 5 W m-2) were used, and the changes in photosynthetic pigments, cell morphology, mycosporine-like amino acids (MAAs) synthesis and cell metabolism were comparatively investigated. Under high UV-B intensity or long term radiation, chlorophyll a, allophycocyanin and phycocyanin were greatly decreased; scanning electron microscope observations showed that cell morphology significantly changed. To reduce the damage, cells synthesized a large amount of carotenoid. Moreover, three kinds of MAAs were identified, and their concentrations varied with the changes of UV-B intensity. Under 1 W m-2 radiation, cells synthesized shinorine and porphyra-334 against UV-B, while with the increase of intensity, more shinorine turned into asterine-330. Metabolite profiling revealed the contents of some cytoprotective metabolites were greatly increased under 5 W m-2 radiation. The principal component analysis showed cells exposed to UV-B were metabolically distinct from the control sample, and the influence on metabolism was particularly dependent on intensity. The results would improve the understanding of physiological responses of N. flagelliforme to UV-B radiation and provide an important theoretical basis for applying this organism to control desertification.
RESUMO
The low-density lipoprotein receptor-related protein 1 (LRP1) gene is associated with increased levels of plasma factor VIII (FVIII). We aimed to explore eight functional genetic LRP1 variants for their potential roles in regulating FVIII levels and acute ischemic stroke (AIS). This genetic association study enrolled 192 patients with AIS and 134 controls. There were no significant differences in the genetic frequency of the eight functional single-nucleotide polymorphisms (SNPs) between the control and AIS groups. However, while analyzing the association between the eight SNPs and plasma FVIII levels, subjects with T/T genotype of rs1800137 (vs. CC+CT) were found to be associated with higher FVIII levels (23.5IU/dL; 95% confidence interval, 7.4-39.5IU/dL; P=0.0044) after adjusting for age, gender, estimated glomerular filtration rate, O blood type, inflammatory state, and body mass index. An analysis of the mRNA stability and abundance was designed and performed using minigene system transfected into HepG2 cells to assess the possible differences in mRNA stabilities between rs1800137 CC (rs1800137C) and TT (rs1800137T) genotypes. Site-directed mutagenesis revealed that rs1800137T accounts for the observed decrease in mRNA stability. The SNP rs1800137, located in exon 8, has been identified as an exon-splicing enhancer in silico. However, alternative splicing of LRP1 without inclusion of exon 8 was not identified. In transfected HepG2 cells, cycloheximide slowed down the degradation of the rs1800137T-containing minigene. These results demonstrate that synonymous SNP rs1800137 can lead to increased plasma FVIII levels due to decreased mRNA stability via translation-dependent mRNA degradation associated with codon optimality.
Assuntos
Isquemia Encefálica , Fator VIII , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Polimorfismo de Nucleotídeo Único , Estabilidade de RNA/genética , RNA Mensageiro , Acidente Vascular Cerebral , Processamento Alternativo/genética , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Fator VIII/biossíntese , Fator VIII/genética , Feminino , Células Hep G2 , Humanos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologiaRESUMO
BACKGROUND: The risk of symptomatic infarct swelling has been reported to be higher in patients treated with recombinant tissue plasminogen activator (rt-PA). The aim of this study was to evaluate the timing of symptomatic infarct swelling after rt-PA treatment. METHODS: We retrospectively analyzed 14 868 patients with acute ischemic stroke from a stroke registry databank. We recruited patients with massive middle cerebral artery (MCA) infarction and symptomatic infarct swelling and excluded those with parenchymal or symptomatic hemorrhage. Multiple linear regression and multivariate logistic regression analyses were used to estimate the impact of rt-PA on the timing of symptomatic infarct swelling. RESULTS: A total of 23 patients with rt-PA treatment and 117 patients without rt-PA treatment were included. The rt-PA treatment group had a lower rate of coronary artery disease (8.7% vs 32.5%; P = .023), lower severity of baseline National Institutes of Health Stroke Scale score (19 vs 23; P = .014), shorter duration of infarct swelling (27.6 vs 45.4 hours; P < .001), and higher rate of hemicraniectomy surgery (65.2% vs 28.2%; P =.001) than those without rt-PA treatment. After adjusting for variables in multiple linear regression analysis, rt-PA treatment and an elevated C-reactive protein level were associated with early symptomatic infarct swelling ( P = .014 and P = .041, respectively). The rt-PA treatment was an independent factor related to early symptomatic infarct swelling within 36 hours ( P = .005; odds ratio [OR]: 5.3; confidence interval [CI]: 1.65-17.0) or 48 hours ( P = .009; OR: 16.4; CI: 2.00-134). CONCLUSION: Intravenous rt-PA treatment may hasten the onset of cerebral edema and subsequent cerebral herniation in large MCA territory infarction.