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1.
Commun Biol ; 7(1): 843, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987326

RESUMO

Bcr-Abl transformation leads to chronic myeloid leukemia (CML). The acquirement of T315I mutation causes tyrosine kinase inhibitors (TKI) resistance. This study develops a compound, JMF4073, inhibiting thymidylate (TMP) and cytidylate (CMP) kinases, aiming for a new therapy against TKI-resistant CML. In vitro and in vivo treatment of JMF4073 eliminates WT-Bcr-Abl-32D CML cells. However, T315I-Bcr-Abl-32D cells are less vulnerable to JMF4073. Evidence is presented that ATF4-mediated upregulation of GSH causes T315I-Bcr-Abl-32D cells to be less sensitive to JMF4073. Reducing GSH biosynthesis generates replication stress in T315I-Bcr-Abl-32D cells that require dTTP/dCTP synthesis for survival, thus enabling JMF4073 susceptibility. It further shows that the levels of ATF4 and GSH in several human CML blast-crisis cell lines are inversely correlated with JMF4073 sensitivity, and the combinatory treatment of JMF4073 with GSH reducing agent leads to synthetic lethality in these CML blast-crisis lines. Altogether, the investigation indicates an alternative option in CML therapy.


Assuntos
Glutationa , Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Glutationa/metabolismo , Humanos , Animais , Camundongos , Inibidores de Proteínas Quinases/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas de Fusão bcr-abl/metabolismo , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/antagonistas & inibidores
2.
Chaos ; 34(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38953752

RESUMO

The synchronous meshing of the gear pair and the screw pair is a typical feature of the planetary roller screw mechanism. In order to fully derive and analyze the nonlinear dynamic characteristics of the system, this paper creatively incorporates the time-varying meshing stiffness of gear pair and the comprehensive transmission error into the research content. Combined with the thread contact force and friction force between the roller and the screw and between the roller and the nut, the nonlinear dynamic model of the planetary roller screw mechanism considering the meshing excitation of the gear pair is established. According to the time domain diagram, frequency domain diagram, phase plane diagram, Poincaré section diagram, three-dimensional spectrum diagram, and spatial phase diagram, the nonlinear behavior of the system is described in detail, and the bifurcation evolution process of the system under the excitation frequency parameters of the external load is revealed. In addition, based on the theory of multi-scale method and considering the variables such as meshing stiffness, meshing damping, and load fluctuation, the stability equation of the primary resonance of the system is derived. The analysis of the stability of the system under different working conditions shows that the parameters are selected within a reasonable range, which effectively reduces the primary common amplitude value and enhances the overall stability of the system. The research content improves the previous system dynamics modeling method and provides a theoretical basis for the nonlinear dynamics modeling method and parameter optimization design of the planetary roller screw mechanism.

4.
Nat Immunol ; 25(1): 41-53, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38036767

RESUMO

Bacille Calmette-Guérin (BCG) vaccination can confer nonspecific protection against heterologous pathogens. However, the underlying mechanisms remain mysterious. We show that mice vaccinated intravenously with BCG exhibited reduced weight loss and/or improved viral clearance when challenged with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 B.1.351) or PR8 influenza. Protection was first evident between 14 and 21 d post-vaccination and lasted ∼3 months. Notably, BCG induced a biphasic innate response and robust antigen-specific type 1 helper T cell (TH1 cell) responses in the lungs. MyD88 signaling was essential for innate and TH1 cell responses, and protection against SARS-CoV-2. Depletion of CD4+ T cells or interferon (IFN)-γ activity before infection obliterated innate activation and protection. Single-cell and spatial transcriptomics revealed CD4-dependent expression of IFN-stimulated genes in lung myeloid and epithelial cells. Notably, BCG also induced protection against weight loss after mouse-adapted SARS-CoV-2 BA.5, SARS-CoV and SHC014 coronavirus infections. Thus, BCG elicits integrated organ immunity, where CD4+ T cells feed back on tissue myeloid and epithelial cells to imprint prolonged and broad innate antiviral resistance.


Assuntos
Imunidade Adaptativa , Vacina BCG , Animais , Camundongos , Humanos , Retroalimentação , Vacinação , Redução de Peso , Antivirais , Imunidade Inata
5.
Small ; 19(45): e2303915, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37420323

RESUMO

Designing superb dielectric capacitors is valuable but challenging since achieving simultaneously large energy-storage (ES) density and high efficiency is difficult. Herein, the synergistic effect of grain refining, bandgap widening, and domain engineering is proposed to boost comprehensive ES properties by incorporating CaTiO3 into 0.92NaNbO3 -0.08BiNi0.67 Ta0.33 O3 matrix (as abbreviated NN-BNT-xCT). Apart from grain refining and bandgap widening, multiple local distortions embedded in labyrinthine submicro-domains, as indicated by diffraction-freckle splitting and ½-type superlattices, produce slush-like polar clusters for the NN-BNT-0.2CT ceramic, which should be ascribed to the coexisting P4bm, P21 ma, and Pnma2 phases. Consequently, a high recoverable ES density Wrec of ≈ 7.1 J cm-3 and a high efficiency η of ≈ 90% at 646 kV cm-1 is achieved for the NN-BNT-0.2CT ceramic. Such hierarchically polar structure is favorable to superb comprehensive ES properties, which provide a strategy for developing high-performance dielectric capacitors.

6.
Opt Express ; 30(18): 32528-32539, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36242312

RESUMO

The adaptive interferometer has been recently proposed to realize the metrology of unknown freeform surfaces with several restructured algorithms for feedback control. The adaptive moment estimation (Adam) stochastic parallel gradient descent (SPGD) algorithm is employed in this paper for fringes release. The proposed algorithm makes considerable progress in relieving conflict of the convergence rate, speed, and parameters intervention. Simulations and experiments show its 37% time saving and 99% convergence rate, with arbitrarily configured parameter increment, compared with the SPGD algorithm. It would have great potential in in-process tests in freeform surface fabrication or large-volume testing.

8.
Mol Genet Genomic Med ; 10(6): e1943, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35388601

RESUMO

BACKGROUND: Mitochondrial disease (MD) is genetically a heterogeneous group of disorders with impairment in respiratory chain complexes or pathways associated with the mitochondrial function. Nowadays, it is still a challenge for the genetic screening of MD due to heteroplasmy of mitochondrial genome and the complex model of inheritance. This study was designed to investigate the feasibility of whole exome sequencing (WES)-based testing as an alternative option for the diagnosis of MD. METHODS: A Chinese Han cohort of 48 patients with suspect MD features was tested using nanoWES, which was a self-designed WES technique that covered the complete mtDNA genome and 21,019 nuclear genes. Fourteen patients were identified with a single genetic variant and three with single deletion in mtDNA. RESULTS: The heteroplasmy levels of variants in mitochondrial genome range from 11% to 100%. NanoWES failed to identify multiple deletions in mtDNA compared with long range PCR and massively parallel sequencing (LR-PCR/MPS). However, our testing showed obvious advantages in identifying variations in nuclear DNA. Based on nanoWES, we identified two patients with nuclear DNA variation. One of them showed Xp22.33-q28 duplication, which indicated a possibility of Klinefelter syndrome. CONCLUSION: NanoWES yielded a diagnostic rate of 35.4% for MD. With the rapid advances of next generation sequencing technique and decrease in cost, we recommend the usage of nanoWES as a first-line method in clinical diagnosis.


Assuntos
DNA Mitocondrial , Doenças Mitocondriais , DNA Mitocondrial/genética , Humanos , Mitocôndrias/genética , Doenças Mitocondriais/diagnóstico , Doenças Mitocondriais/genética , Análise de Sequência de DNA/métodos , Sequenciamento do Exoma
9.
Opt Lett ; 47(21): 5449-5452, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219241

RESUMO

In addition to the concept of picometer resolution, we discuss macro displacement measurement with a vortex beam interferometer. Three factors limiting large displacement measurement are resolved. Small topological charge numbers promise both high sensitivity and large displacement measurements. With a computing visual method, a virtual moiré pointer image immune to beam misalignment is proposed to calculate displacements. Interestingly, the absolute benchmark is found for cycle counting in the moiré pointer image of fractional topological charge. The vortex beam interferometer would not stop at the tiny displacement measurement in simulations. We report experimental measurements of nanoscale to hundred millimeter displacement in a vortex beam displacement measurement interferometer (DMI) for the first time, to the best of our knowledge.

10.
Int J Mol Sci ; 22(22)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34830077

RESUMO

The CHYR (CHY ZINC-FINGER AND RING FINGER PROTEIN) proteins have been functionally characterized in iron regulation and stress response in Arabidopsis, rice and Populus. However, their roles in soybean have not yet been systematically investigated. Here, in this study, 16 GmCHYR genes with conserved Zinc_ribbon, CHY zinc finger and Ring finger domains were obtained and divided into three groups. Moreover, additional 2-3 hemerythrin domains could be found in the N terminus of Group III. Phylogenetic and homology analysis of CHYRs in green plants indicated that three groups might originate from different ancestors. Expectedly, GmCHYR genes shared similar conserved domains/motifs distribution within the same group. Gene expression analysis uncovered their special expression patterns in different soybean tissues/organs and under various abiotic stresses. Group I and II members were mainly involved in salt and alkaline stresses. The expression of Group III members was induced/repressed by dehydration, salt and alkaline stresses, indicating their diverse roles in response to abiotic stress. In conclusion, our work will benefit for further revealing the biological roles of GmCHYRs.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glycine max , Família Multigênica , Proteínas de Soja , Ubiquitina-Proteína Ligases , Estudo de Associação Genômica Ampla , Proteínas de Soja/biossíntese , Proteínas de Soja/genética , Glycine max/enzimologia , Glycine max/genética , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitina-Proteína Ligases/genética
11.
Am J Transl Res ; 13(7): 7921-7927, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34377271

RESUMO

OBJECTIVE: This study aimed to investigate the feasibility of epidural injection of ropivacaine (Rop) and dexamethasone (Dex) for labor analgesia in women with preeclampsia. METHODS: A total of 80 women with preeclampsia delivered in our hospital were enrolled, and were divided into a study group (n=41, Rop + Dex) and a control group (n=39, Rop alone). The changes in pain level, sedation, catecholamine hormone levels and vital signs were compared between the two groups after intervention. The motor blockade score and the incidence of adverse reactions after administration of anesthesia were compared in both groups. RESULTS: Pain level [visual analogue scale (VAS) score], sedation (Ramsay score), adrenaline (AD), norepinephrine (NE), heart rate (HR), and mean arterial pressure (MAP) did not differ significantly between the two groups at pre-analgesia (T0) (P>0.05), and Ramsay score in the study group was significantly higher than that in the control group at 30 min (T1), 60 min (T2), 120 min after analgesia (T3), and cessation of analgesia (T4), and VAS score, AD, NE, HR, MAP in the study group were significantly lower than those in the control group during all stages of labor. CONCLUSION: The epidural injection of Rop + Dex in women with preeclampsia can play a better analgesic and sedative effect, stabilize maternal hemodynamic index and improve postpartum motor blockade.

12.
Am J Transl Res ; 13(7): 8110-8117, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34377294

RESUMO

PURPOSE: This study aimed to investigate the effects of high-dose rocuronium bromide in general anesthesia for spinal surgery and analyze its safety. METHODS: A total of 90 patients with spine diseases who underwent elective spinal surgery in our hospital were enrolled as study subjects, and were divided into 2-fold group (intraoperative administration of 0.6 mg/kg rocuronium bromide, n=30), 3-fold group (0.9 mg/kg rocuronium bromide, n=30) and 4-fold group (1.2 mg/kg rocuronium bromide, n=30). The effects of rocuronium bromide on muscle relaxation, the operative time and the incidence of adverse reactions were compared among the three groups. RESULTS: The onset time of muscle relaxation in the 4-fold group was significantly lower than that in 2-fold and 3-fold groups. The duration of muscle relaxation and duration of action in the 4-fold group were significantly higher than those in the 2-fold and 3-fold groups (P<0.05). The satisfaction rate in the 4-fold group (100.00%) was significantly higher than that in the 2-fold group (66.67%) and the 3-fold group (86.67%) (P<0.05). The 4-fold group exhibited significantly higher intubating condition score at 1 min and significantly lower operative time than the 2-fold and 3-fold groups (P<0.05). The incidence of adverse reactions in the 4-fold group was 23.33%, slightly higher than those in the 2-fold (20.00%) and 3-fold groups (20.00%) (P>0.05). CONCLUSION: High-dose rocuronium bromide shortens the onset time of muscle relaxation in patients undergoing spinal surgery, creates better intubation conditions, has longer duration of action, and shortens the patient's operative time, without increasing adverse reactions such as skin flushing, rash, increased airway resistance and bronchospasm, laryngeal edema, etc. Meanwhile, high-dose rocuronium bromide can shorten intubation time, which is conducive to the smooth operation and reduces surgical stress injuries.

13.
BMC Genomics ; 22(1): 407, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082700

RESUMO

BACKGROUND: Next-generation sequencing (NGS) is an efficient tool used for identifying pathogenic variants that cause Mendelian disorders. However, the lack of bioinformatics training of researchers makes the interpretation of identified variants a challenge in terms of precision and efficiency. In addition, the non-standardized phenotypic description of human diseases also makes it difficult to establish an integrated analysis pathway for variant annotation and interpretation. Solutions to these bottlenecks are urgently needed. RESULTS: We develop a tool named "Cruxome" to automatically annotate and interpret single nucleotide variants (SNVs) and small insertions and deletions (InDels). Our approach greatly simplifies the current burdensome task of clinical geneticists and scientists to identify the causative pathogenic variants and build personal knowledge reference bases. The integrated architecture of Cruxome offers key advantages such as an interactive and user-friendly interface and the assimilation of electronic health records of the patient. By combining a natural language processing algorithm, Cruxome can efficiently process the clinical description of diseases to HPO standardized vocabularies. By using machine learning, in silico predictive algorithms, integrated multiple databases and supplementary tools, Cruxome can automatically process SNVs and InDels variants (trio-family or proband-only cases) and clinical diagnosis records, then annotate, score, identify and interpret pathogenic variants to finally generate a standardized clinical report following American College of Medical Genetics and Genomics/ Association for Molecular Pathology (ACMG/AMP) guidelines. Cruxome also provides supplementary tools to examine and visualize the genes or variations in historical cases, which can help to better understand the genetic basis of the disease. CONCLUSIONS: Cruxome is an efficient tool for annotation and interpretation of variations and dramatically reduces the workload for clinical geneticists and researchers to interpret NGS results, simplifying their decision-making processes. We present an online version of Cruxome, which is freely available to academics and clinical researchers. The site is accessible at http://114.251.61.49:10024/cruxome/ .


Assuntos
Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Algoritmos , Biologia Computacional , Bases de Dados Genéticas , Variação Genética , Humanos , Mutação INDEL , Software
14.
Mol Plant ; 14(8): 1343-1361, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34015460

RESUMO

Cereal endosperm comprises an outer aleurone and an inner starchy endosperm. Although these two tissues have the same developmental origin, they differ in morphology, cell fate, and storage product accumulation, with the mechanism largely unknown. Here, we report the identification and characterization of rice thick aleurone 1 (ta1) mutant that shows an increased number of aleurone cell layers and increased contents of nutritional factors including proteins, lipids, vitamins, dietary fibers, and micronutrients. We identified that the TA1 gene, which is expressed in embryo, aleurone, and subaleurone in caryopses, encodes a mitochondrion-targeted protein with single-stranded DNA-binding activity named OsmtSSB1. Cytological analyses revealed that the increased aleurone cell layers in ta1 originate from a developmental switch of subaleurone toward aleurone instead of starchy endosperm in the wild type. We found that TA1/OsmtSSB1 interacts with mitochondrial DNA recombinase RECA3 and DNA helicase TWINKLE, and downregulation of RECA3 or TWINKLE also leads to ta1-like phenotypes. We further showed that mutation in TA1/OsmtSSB1 causes elevated illegitimate recombinations in the mitochondrial genome, altered mitochondrial morphology, and compromised energy supply, suggesting that the OsmtSSB1-mediated mitochondrial function plays a critical role in subaleurone cell-fate determination in rice.


Assuntos
Proteínas de Ligação a DNA/genética , Mitocôndrias/metabolismo , Mutação/genética , Oryza/genética , Proteínas de Plantas/genética , Endosperma/genética , Regulação da Expressão Gênica de Plantas/genética , Fenótipo , Sementes/genética , Amido/genética
15.
Laryngoscope ; 131(6): E1847-E1853, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33141455

RESUMO

OBJECTIVES: The role of locoregional radiotherapy for metastatic oropharyngeal squamous cell cancer (OPSCC) is unclear. We investigated the impact of head and neck radiotherapy on survival in de novo metastatic OPSCC patients who received systemic therapy. METHODS: We queried the NCDB from 2004-2015 for metastatic OPSCC patients at diagnosis with known HPV-status who received systemic therapy. The association of head and neck radiotherapy with overall survival was analyzed using the Kaplan-Meier method, Cox proportional hazards model, and propensity score-matched analysis adjusting for demographic and disease-specific prognostic factors. RESULTS: Of the 2,139 patients with metastatic OPSCC who presented with metastases and received systemic treatment, we identified 556 patients with known HPV-status. Among these 556 patients, 49% were HPV-positive and 56% received head and neck radiotherapy. With a median follow-up of 17.5 months (IQR 6.0-163.4 months), radiotherapy was associated with significantly improved 1-year OS (67% vs 58%, log-rank P < .001) which remained significant on MVA (HR 0.78 95% CI 0.62-0.97 P = .029). In HPV-status subgroup analysis, a survival benefit was identified in HPV-positive patients (1-year OS 77% vs 67%, log-rank P < .001) but not in HPV-negative patients. Results were consistent on a propensity score-matched analysis of 212 HPV-positive matched patients (HR 0.66, 95% CI 0.49-0.83, P < .001). CONCLUSION: The survival of metastatic OPSCC remains limited. In this large series of patients with known HPV-status, head and neck radiotherapy was associated with longer survival in those with HPV-associated disease. These data could guide management of this challenging group of patients for head and neck cancer practitioners. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:E1847-E1853, 2021.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/complicações , Prognóstico , Pontuação de Propensão , Taxa de Sobrevida
16.
J Endod ; 46(9): 1256-1264, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32505637

RESUMO

INTRODUCTION: Biomaterials designed for tissue engineering should be nontoxic and nonimmunogenic and should achieve their intended functions. Treated dentin matrix (TDM), a bioactive extracellular matrix, is promising for tooth regeneration. However, the effect of sterilization on the surface properties of allogenous TDM in the animal model is unclear. METHODS: The biological characteristics and influences of dental pulp stem cells (DPSCs) with autoclaved TDM (a-TDM) were studied using scanning electron microscopy, immunofluorescence microscopy, immunohistochemistry, and reverse transcription polymerase chain reaction in vitro. In addition, a-TDM was implanted in a mouse model for 6 weeks and was a substrate with DPSCs for tooth reconstruction in a goat animal model in vivo. RESULTS: Allogenous a-TDM induced and supported DPSCs to develop new dentin pulp-like tissues, enamel dental pulp, and cementum periodontal complexes. Immunohistochemistry data showed that the markers dentin sialoprotein, ßⅢ-tubulin, dentin matrix protein 1, amelogenin, VIII factors, type I collagen, cementum-derived attachment protein, and scleraxis transcription factor were positive stained in toothlike tissue. CONCLUSIONS: Allogenous a-TDM served as an effective scaffold enabling DPSCs to proliferate and differentiate into a broad array of resident cells including odontoblasts, fibroblasts, vascular cells, and neural endings. Allogenous a-TDM with DPSCs can provide an ideal biomaterial for optimizing the regeneration of tooth material.


Assuntos
Polpa Dentária , Dentina , Animais , Diferenciação Celular , Células Cultivadas , Camundongos , Regeneração , Células-Tronco , Esterilização , Alicerces Teciduais
17.
Plant Sci ; 296: 110469, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32539999

RESUMO

Rapid and low-cost methods of detecting mutations and polymorphisms are crucial for genotyping applications including mutagenesis and gene editing. S1 family endonucleases such as T7E1, EndoV and CELI can potentially be used in enzymatic mismatch detection. Among them, CELI has been shown to be effective in detecting mutations in Targeting Induced Local Lesions IN Genomes (TILLING). However, current method of CELI purification from celery is laborious, and challenging for many non-biochemical laboratories, and the presence of post-translational modifications hinders efficient production of the enzyme in E. coli. Here, we report an efficient system for bulk production of enzymatically active CELI endonuclease through transient expression in a model plant Nicotiana benthamiana. We also optimized the reaction buffer, by additions of Mn2+ and DTT, with enhanced mismatch cleavage activity. Using the new CELI production and reaction system, we were able to routinely detect mismatches in 1/32 mixed mutant and wildtype DNA samples. We believe the newly established system has many applications in characterization of mutations occurred in natural variations, mutagenized populations and gene editing.


Assuntos
Endonucleases/metabolismo , Edição de Genes , Mutação , Nicotiana/metabolismo , Apium/enzimologia , Apium/genética , Apium/metabolismo , Expressão Gênica , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Proteínas Recombinantes , Nicotiana/enzimologia , Nicotiana/genética
18.
Bio Protoc ; 10(16): e3716, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-33659380

RESUMO

Fungal pathogen Candida albicans is one of the top leading causes of overall healthcare-associated bloodstream infections worldwide. Neutrophil is the major effector cell to clear C. albicans infection. Our study showed that mouse neutrophils utilize two independent mechanisms to kill C. albicans: one is CR3 downstream NADPH oxidase-dependent mechanism that kills opsonized C. albicans; the other one is dectin-2-mediated NADPH oxidase-independent neutrophil extracellular trap (NET) that kills unopsonized C. albicans. Neutrophil killing of opsonized C. albicans requires phagocytosing the organism and production of reactive oxygen species production (ROS). Most existing protocols that assay for neutrophil killing of C. albicans requires a washing step after allowing neutrophils to phagocytose the organism. By definition, NET kills organisms extracellularly. Therefore, it is important to skip the washing step and add an optimal ratio of neutrophils and C. albicans to the wells. To demonstrate the effect of NET, it is necessary to compare killing ability of neutrophils treated with micrococcal nuclease (MNase), an enzyme that digests NET, to that treated with heat-inactivated MNase. MNase is also applied to release NET-bound fungal elements for counting. This protocol can be applied to assay NET killing of other biofilm-forming organisms.

19.
PLoS Pathog ; 15(11): e1008096, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31693704

RESUMO

Candida albicans is one of the top leading causes of healthcare-associated bloodstream infection. Neutrophil extracellular traps (NET) are known to capture and kill pathogens. It is reported that opsonized C. albicans-triggered NETosis is NADPH oxidase-dependent. We discovered a NADPH oxidase-independent NETosis pathway in neutrophil response to unopsonized C. albicans. While CR3 engagement with opsonized C. albicans triggered NET, dectin-2 recognized unopsonized C. albicans and mediated NET formation. Engagement of dectin-2 activated the downstream Syk-Ca2+-PKCδ-protein arginine deiminase 4 (PAD4) signaling pathway which modulated nuclear translocation of neutrophil elastase (NE), histone citrullination and NETosis. In a C. albicans peritonitis model we observed Ki67+Ly6G+ NETotic cells in the peritoneal exudate and mesenteric tissues within 3 h of infection. Treatment with PAD4 inhibitor GSK484 or dectin-2 deficiency reduced % Ki67+Ly6G+ cells and the intensity of Ki67 in peritoneal neutrophils. Employing DNA digestion enzyme micrococcal nuclease, GSK484 as well as dectin-2-deficient mice, we further showed that dectin-2-mediated PAD4-dependent NET formation in vivo restrained the spread of C. albicans from the peritoneal cavity to kidney. Taken together, this study reveals that unopsonized C. albicans evokes NADPH oxidase-independent NETosis through dectin-2 and its downstream signaling pathway and dectin-2-mediated NET helps restrain fungal dissemination.


Assuntos
Candida albicans/imunologia , Candidíase/imunologia , Armadilhas Extracelulares/imunologia , Rim/imunologia , Lectinas Tipo C/metabolismo , NADPH Oxidases/metabolismo , Peritônio/imunologia , Animais , Candidíase/metabolismo , Candidíase/microbiologia , Rim/metabolismo , Lectinas Tipo C/genética , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidases/genética , Peritônio/metabolismo , Fagocitose , Espécies Reativas de Oxigênio , Transdução de Sinais
20.
BMC Plant Biol ; 19(1): 25, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30642256

RESUMO

Following publication of the original article [1], the author reported that their given name was misspelled.

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