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Mosquitoes bring global health problems by transmitting parasites and viruses such as malaria and dengue. Unfortunately, current insecticide-based control strategies are only moderately effective because of high cost and resistance. Thus, scalable, sustainable, and cost-effective strategies are needed for mosquito-borne disease control. Symbiont-based and genome engineering-based approaches provide new tools that show promise for meeting these criteria, enabling modification or suppression approaches. Symbiotic bacteria like Wolbachia are maternally inherited and manipulate mosquito host reproduction to enhance their vertical transmission. Genome engineering-based gene drive methods, in which mosquitoes are genetically altered to spread drive alleles throughout wild populations, are also proving to be a potentially powerful approach in the laboratory. Here, we review the latest developments in both symbionts and gene drive-based methods. We describe some notable similarities, as well as distinctions and obstacles, relating to these promising technologies.
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Culicidae , Tecnologia de Impulso Genético , Malária , Wolbachia , Animais , Culicidae/genética , Malária/genética , Malária/prevenção & controle , Mosquitos Vetores/genética , Wolbachia/genéticaRESUMO
Targeting cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) with specific antibody offers long-term benefits for cancer immunotherapy but can cause severe adverse effects in the heart. This study aimed to investigate the role of anti-CTLA-4 antibody in pressure overload-induced cardiac remodeling and dysfunction. Transverse aortic constriction (TAC) was used to induce cardiac hypertrophy and heart failure in mice. Two weeks after the TAC treatment, mice received anti-CTLA-4 antibody injection twice a week at a dose of 10 mg/kg body weight. The administration of anti-CTLA-4 antibody exacerbated TAC-induced decline in cardiac function, intensifying myocardial hypertrophy and fibrosis. Further investigation revealed that anti-CTLA-4 antibody significantly elevated systemic inflammatory factors levels and facilitated the differentiation of T helper 17 (Th17) cells in the peripheral blood of TAC-treated mice. Importantly, anti-CTLA-4 mediated differentiation of Th17 cells and hypertrophic phenotype in TAC mice were dramatically alleviated by the inhibition of interleukin-17A (IL-17A) by an anti-IL-17A antibody. Furthermore, the C-X-C motif chemokine receptor 4 (CXCR4) antagonist AMD3100, also reversed anti-CTLA-4-mediated cardiotoxicity in TAC mice. Overall, these results suggest that the administration of anti-CTLA-4 antibody exacerbates pressure overload-induced heart failure by activating and promoting the differentiation of Th17 cells. Targeting the CXCR4/Th17/IL-17A axis could be a potential therapeutic strategy for mitigating immune checkpoint inhibitors-induced cardiotoxicity.
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Antígeno CTLA-4 , Insuficiência Cardíaca , Camundongos Endogâmicos C57BL , Células Th17 , Animais , Células Th17/imunologia , Células Th17/metabolismo , Camundongos , Antígeno CTLA-4/metabolismo , Antígeno CTLA-4/antagonistas & inibidores , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Masculino , Interleucina-17/metabolismo , Receptores CXCR4/metabolismo , Receptores CXCR4/antagonistas & inibidores , Diferenciação Celular , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/etiologiaRESUMO
Mosquito-borne diseases, such as dengue and malaria, pose a significant burden to global health. Current control strategies with insecticides are only moderately effective. Scalable solutions are needed to reduce the transmission risk of these diseases. Symbionts and genome engineering-based mosquito control strategies have been proposed to address these problems. Bacterial, fungal, and viral symbionts affect mosquito reproduction, reduce mosquito lifespan, and block pathogen transmission. Field tests of endosymbiont Wolbachia-based methods have yielded promising results, but there are hurdles to overcome due to the large-scale rearing and accurate sex sorting required for Wolbachia-based suppression approaches and the ecological impediments to Wolbachia invasion in replacement approaches. Genome engineering-based methods, in which mosquitoes are genetically altered for the modification or suppression of wild populations, offer an additional approach for control of mosquito-borne diseases. In particular, the use of gene drive alleles that bias inheritance in their favor is a potentially powerful approach. Several drives are frequency dependent, potentially giving them broadly similar population dynamics to Wolbachia. However, public acceptance and the behavior of released drives in natural mosquito populations remain challenges. We summarize the latest developments and discuss the knowledge gaps in both symbiont- and gene drive-based methods.
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Realizing the immense clinical potential of mRNA-based drugs will require continued development of methods to safely deliver the bioactive agents with high efficiency and without triggering side effects. In this regard, lipid nanoparticles have been successfully utilized to improve mRNA delivery and protect the cargo from extracellular degradation. Encapsulation in lipid nanoparticles was an essential factor in the successful clinical application of mRNA vaccines, which conclusively demonstrated the technology's potential to yield approved medicines. In this review, we begin by describing current advances in mRNA modifications, design of novel lipids and development of lipid nanoparticle components for mRNA-based drugs. Then, we summarize key points pertaining to preclinical and clinical development of mRNA therapeutics. Finally, we cover topics related to targeted delivery systems, including endosomal escape and targeting of immune cells, tumors and organs for use with mRNA vaccines and new treatment modalities for human diseases.
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Sistemas de Liberação de Medicamentos , Nanopartículas , RNA Mensageiro , Humanos , RNA Mensageiro/genética , RNA Mensageiro/administração & dosagem , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Vacinas de mRNA , Lipídeos/química , LipossomosRESUMO
Despite numerous data on organophosphate tri-esters (tri-OPEs) in the environment, literatures on organophosphate di-esters (di-OPEs) in field environment, especially marine sediments remain scarce. This study addresses this gap by analyzing 35 abyssal sediment samples from the middle Okinawa Trough in the East China Sea. A total of 25 tri-OPEs and 10 di-OPEs were determined, but 13 tri-OPEs and 2 di-OPEs were nondetectable in any of these sediment samples. The concentrations of ∑12tri-OPE and ∑8di-OPE were 0.108-32.2 ng/g (median 1.11 ng/g) and 0.548-15.0 ng/g (median 2.74 ng/g). Chlorinated (Cl) tri-OPEs were the dominant tri-esters, accounting for 47.5 % of total tri-OPEs on average, whereas chlorinated di-OPEs represented only 19.2 % of total di-OPEs. This discrepancy between the relatively higher percentage of Cl-tri-OPEs and lower abundance of Cl-di-OPEs may be ascribed to the stronger environmental persistence of chlorinated tri-OPEs. Source assessment suggested that di-OPEs were primarily originated from the degradation of tri-OPEs rather than industrial production. Long range waterborne transport facilitated by oceanic currents was an important input pathway for OPEs in sediments from the Okinawa Trough. These findings enhance the understanding of the sources and transport of OPEs in marine sediments, particularly in the Okinawa Trough.
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Monitoramento Ambiental , Retardadores de Chama , Ésteres , Retardadores de Chama/análise , China , Organofosfatos , Sedimentos GeológicosRESUMO
The liver plays an important role in regulating lipid metabolism in animals. This study investigated the function and mechanism of lncLLM in liver lipid metabolism in hens at the peak of egg production. The effect of lncLLM on intracellular lipid content in LMH cells was evaluated by qPCR, Oil Red O staining, and detection of triglyceride (TG) and cholesterol (TC) content. The interaction between lncLLM and MYH9 was confirmed by RNA purification chromatin fractionation (CHIRP) and RNA immunoprecipitation (RIP) analysis. The results showed that lncLLM increased the intracellular content of TG and TC and promoted the expression of genes related to lipid synthesis. It was further found that lncLLM had a negative regulatory effect on the expression level of MYH9 protein in LMH cells. The intracellular TG and TC content of MYH9 knockdown cells increased, and the expression of genes related to lipid decomposition was significantly reduced. In addition, this study confirmed that the role of lncLLM is at least partly through mediating the ubiquitination of MYH9 protein to accelerate the degradation of MYH9 protein. This discovery provides a new molecular target for improving egg-laying performance in hens and treating fatty liver disease in humans.
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Galinhas , Metabolismo dos Lipídeos , Cadeias Pesadas de Miosina , RNA Longo não Codificante , Ubiquitinação , Animais , Cadeias Pesadas de Miosina/metabolismo , Cadeias Pesadas de Miosina/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Triglicerídeos/metabolismo , Colesterol/metabolismo , Linhagem Celular , Fígado/metabolismoRESUMO
The concept of reference sample was put forward in the Guidance on CMC of Traditional Chinese Medicine Compound Preparations Developed from Catalogued Ancient Classical Prescriptions(Interim). The research on reference sample is a key link in the research and development of traditional Chinese medicine(TCM) compound prescriptions from catalogued ancient classical prescriptions(known as Category 3.1 TCM). This paper discusses the content of research on reference sample by analyzing the characteristics of Category 3.1 TCM and the purpose of research on reference sample. Furthermore, suggestions on the research of reference sample are proposed according to the development and evaluation practice of Category 3.1 TCM and research achievements of TCM regulatory science, aiming to provide reference for colleagues in this industry.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/química , Humanos , Prescrições de Medicamentos , História Antiga , ChinaRESUMO
BACKGROUND: The association between M segment splicing and pathogenicity remains ambiguous in human influenza A viruses. In this study, we aimed to investigate M splicing in various human influenza A viruses and characterize its physiological roles by applying the splicing inhibitor, herboxidiene. METHODS: We examined the M splicing of human H1N1 and H3N2 viruses by comparing three H1N1 and H3N2 strains, respectively, through reverse transcriptase-polymerase chain reaction (RT-PCR) analyses. We randomly selected M sequences of human H1N1, H2N2, and H3N2 viruses isolated from 1933 to 2020 and examined their phylogenetic relationships. Next, we determined the effects of single nucleotide variations on M splicing by generating mutant viruses harboring the 55C/T variant through reverse genetics. To confirm the importance of M2 splicing in the replication of H1N1 and H3N2, we treated infected cells with splicing inhibitor herboxidiene and analyzed the viral growth using plaque assay. To explore the physiological role of the various levels of M2 protein in pathogenicity, we challenged C57BL/6 mice with the H1N1 WSN wild-type strain, mutant H1N1 (55T), and chimeric viruses including H1N1 + H3wt and H1N1 + H3mut. One-tailed paired t-test was used for virus titer calculation and multiple comparisons between groups were performed using two-way analysis of variance. RESULTS: M sequence splice site analysis revealed an evolutionarily conserved single nucleotide variant C55T in H3N2, which impaired M2 expression and was accompanied by collinear M1 and mRNA3 production. Aberrant M2 splicing resulted from splice-site selection rather than a general defect in the splicing process. The C55T substitution significantly reduced both M2 mRNA and protein levels regardless of the virus subtype. Consequently, herboxidiene treatment dramatically decreased both the H1N1 and H3N2 virus titers. However, a lower M2 expression only attenuated H1N1 virus replication and in vivo pathogenicity. This attenuated phenotype was restored by M replacement of H3N2 M in a chimeric H1N1 virus, despite low M2 levels. CONCLUSIONS: The discrepancy in M2-dependence emphasizes the importance of M2 in human influenza A virus pathogenicity, which leads to subtype-specific evolution. Our findings provide insights into virus adaptation processes in humans and highlights splicing regulation as a potential antiviral target.
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Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Influenza Humana , Animais , Camundongos , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Filogenia , Camundongos Endogâmicos C57BL , Nucleotídeos , Influenza Humana/tratamento farmacológico , Influenza Humana/genéticaRESUMO
mRNA-based drugs have tremendous potential as clinical treatments, however, a major challenge in realizing this drug class will promise to develop methods for safely delivering the bioactive agents with high efficiency and without activating the immune system. With regard to mRNA vaccines, researchers have modified the mRNA structure to enhance its stability and promote systemic tolerance of antigenic presentation in non-inflammatory contexts. Still, delivery of naked modified mRNAs is inefficient and results in low levels of antigen protein production. As such, lipid nanoparticles have been utilized to improve delivery and protect the mRNA cargo from extracellular degradation. This advance was a major milestone in the development of mRNA vaccines and dispelled skepticism about the potential of this technology to yield clinically approved medicines. Following the resounding success of mRNA vaccines for COVID-19, many other mRNA-based drugs have been proposed for the treatment of a variety of diseases. This review begins with a discussion of mRNA modifications and delivery vehicles, as well as the factors that influence administration routes. Then, we summarize the potential applications of mRNA-based drugs and discuss further key points pertaining to preclinical and clinical development of mRNA drugs targeting a wide range of diseases. Finally, we discuss the latest market trends and future applications of mRNA-based drugs.
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COVID-19 , Nanopartículas , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Tolerância a Medicamentos , RNA Mensageiro/genética , RNA Mensageiro/uso terapêutico , Vacinas de mRNA , Nanopartículas/uso terapêuticoRESUMO
BACKGROUND AND OBJECTIVES: We aim to evaluate the analgesic efficacy and safety of erector spinae plane block (ESPB) for postoperative analgesia in breast cancer surgeries. METHODS: PubMed, Web of Science, CBM, Embase, Cochrane, Wanfang, VIPP, and CNKI were searched to identify published eligible randomized controlled trials. The primary results were the postoperative 24 h morphine consumption and pain scores, while the secondary outcomes included pain scores at other times, press times of patient-controlled intravenous analgesia (PCIA), times to request for first rescue analgesia, the incidence of request for rescue analgesia, opioid-related complications, nerve blocks related complications and patient satisfaction. RESULTS: We included 20 studies meeting the inclusion criteria, which involved 1293 participants. The morphine consumption and the pain scores during 24 h postoperatively were significantly decreased in the ESPB group versus the control group (p < 0.00001). Furthermore, ESPB also reduced pain scores at other time points, press times of PCIA, and times to first rescue analgesia requirement. Meanwhile, there was a lower incidence of postoperative nausea and vomiting, and skin pruritus in the ESPB group than in the control group. CONCLUSIONS: Compared to general anesthesia alone, ESPB combined with general anesthesia can effectively reduce the postoperative pain intensity within 48 h and opioid consumption within 24 h after breast cancer surgery, and reduce the incidence of opioid and nerve blocks related complications.
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Neoplasias da Mama , Humanos , Feminino , Analgésicos Opioides , Dor Pós-Operatória , Analgesia Controlada pelo Paciente , Derivados da MorfinaRESUMO
Astroblastoma is an uncommon tumor of the central nervous system. It is variable in morphology, but the astroblastic pseudorosettes and vascular hyalinization are the most important features. Most astroblastomas occur in the cerebral hemisphere. We report a recurrent high-grade astroblastoma with MN1-BEND2 fusion in the spinal cord. Two lesions were found in the T5-7 level and T12-L1 level, and they were well defined in images. Rhabdoid and signet-ring-like cells were observed. It may be classified as a high-grade tumor due to cellularity, high mitotic count, and pleomorphism. The tumor cells were diffusely positive for GFAP, Olig-2, and S-100 protein. We found the MN1 arrangement and the loss of chromosome 1p by FISH, and further validated the BEN domain containing 2 genes (BEND2), which is the fusion partner of meningioma 1 gene (MN1), by next-generation sequencing (NGS) and Sanger sequencing. The MN1 mutation is crucial in the diagnosis and prognosis of rare astroblastoma. The spinal cord astroblastoma may have a high recurrence rate because of the residual lesion at the unique location and higher grade; the connection with the gene mutation is unclear. Regular follow-up is necessary. Further study and more cases are needed to establish evidence for diagnosis, prognosis, and treatment of astroblastoma with molecular characteristics.
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Neoplasias Encefálicas , Neoplasias Meníngeas , Meningioma , Neoplasias Neuroepiteliomatosas , Humanos , Neoplasias Encefálicas/patologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Neoplasias Neuroepiteliomatosas/genética , Neoplasias Neuroepiteliomatosas/patologia , Transativadores , Proteínas Supressoras de Tumor/genéticaRESUMO
OBJECTIVES: A consistent effect of hemodialysis (HD) on vitamin B loss has not been fully demonstrated and the effect of high-flux hemodialysis (HFHD) is also inconclusive. The aim of this study was to identify the loss of vitamin B1, B3, B5, and B6 in a single HD session and to evaluate the effect of HFHD on vitamin B removal. METHODS: Patients on maintenance HD were enrolled in this study. They were divided into low-flux hemodialysis (LFHD) group and HFHD group. Vitamin B1, B3, B5, and B6 (pyridoxal 5'-phosphate [PLP]) concentrations in blood pre- and post-HD sessions, as well as in the spent dialysate were measured. Loss of vitamin B was calculated and the difference in vitamin B loss between the 2 groups was compared. The association between HFHD and vitamin B loss was estimated using multivariable linear regression analysis. RESULTS: Seventy-six patients were included, of whom 29 were on LFHD and 47 were on HFHD. The median reduction ratio of serum vitamins B1, B3, B5, and B6 after a single HD session was 38.1%, 24.9%, 48.4%, and 44.7%, respectively. The median concentration of vitamins B1, B3, B5, and B6 in the dialysate was 0.3 µg/L, 2.9 µg/mL, 2.0 µg/L, and 0.4 ng/mL. There was no difference in either the reduction ratio of vitamin B in blood, or the concentration in dialysate between LFHD and HFHD groups. After adjusting for covariates by multivariable regression, HFHD had no effect on vitamin B1, B3, B5, or B6 removal. CONCLUSIONS: Vitamins B1, B3, B5, and B6 can be removed by HD and HFHD does not increase the loss.
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Diálise Renal , Tiamina , Humanos , Fosfato de Piridoxal , VitaminasRESUMO
OBJECTIVE: Although platelet-derived growth factor receptor (PDGFR)-ß mediates the self-renewal and multipotency of neural stem/progenitor cells (NSPCs) in vitro and in vivo, its mechanisms of activating endogenous NSPCs following ischemic stroke still remain unproven. METHODS: The exogenous NSPCs were transplanted into the ischemic striatum of PDGFR-ß conditionally neuroepithelial knockout (KO) mice at 24 h after transient middle cerebral artery occlusion (tMCAO). 5-Bromo-2'-deoxyuridine (BrdU) was intraperitoneally injected to label the newly formed endogenous NSPCs. Infarction volume was measured, and behavioral tests were performed. In the subventricular zone (SVZ), proliferation of endogenous NSPCs was tested, and synapse formation and expression of nutritional factors were measured. RESULTS: Compared with control mice, KO mice showed larger infarction volume, delayed neurological recovery, reduced numbers of BrdU positive cells, decreased expression of neurogenic factors (including neurofilament, synaptophysin, and brain-derived neurotrophic factor), and decreased synaptic regeneration in SVZ after tMCAO. Moreover, exogenous NSPC transplantation significantly alleviated neurologic dysfunction, promoted neurogenesis, increased expression of neurologic factors, and diminished synaptic deformation in SVZ of FL mice after tMCAO but had no beneficial effect in KO mice. CONCLUSION: PDGFR-ß signaling may promote activation of endogenous NSPCs after postischemic NSPC transplantation, and thus represents a novel potential regeneration-based therapeutic target.
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Células-Tronco Neurais , Camundongos , Animais , Bromodesoxiuridina/metabolismo , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/transplante , Neurogênese/fisiologia , Infarto da Artéria Cerebral Média/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transplante de Células , Proliferação de CélulasRESUMO
Silicon photonics (SiPh) are considered a promising technology for increasing interconnect speed and capacity while decreasing power consumption. Mode division multiplexing (MDM) enables signals to be transmitted in different orthogonal modes in a single waveguide core. Wideband MDM components simultaneously supporting wavelength division multiplexing (WDM) and orthogonal frequency-division multiplexing (OFDM) can significantly increase the transmission capacity for optical interconnects. In this work, we propose, fabricate and demonstrate a wideband and channel switchable MDM optical power divider on an SOI platform, supporting single, dual and triple modes. The switchable MDM power divider consists of two parts. The first part is a cascaded Mach-Zehnder interferometer (MZI) for switching the data from their original TE0, TE1 and TE2 modes to different modes among themselves. After the target modes are identified, mode up-conversion and Y-branch are utilized in the second part for the MDM power division. Here, 48 WDM wavelength channels carrying OFDM data are successfully switched and power divided. An aggregated capacity of 7.682 Tbit/s is achieved, satisfying the pre-forward error correction (pre-FEC) threshold (bit-error-rate, BER = 3.8 × 10-3). Although up to three MDM modes are presented in the proof-of-concept demonstration here, the proposed scheme can be scaled to higher order modes operation.
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Registros , Silício , Estudo de Prova de Conceito , TecnologiaRESUMO
Due to the popularity of different high bandwidth applications, it is becoming increasingly difficult to satisfy the huge data capacity requirements, since the traditional electrical interconnects suffer significantly from limited bandwidth and huge power consumption. Silicon photonics (SiPh) is one of the important technologies for increasing interconnect capacity and decreasing power consumption. Mode-division multiplexing (MDM) allows signals to be transmitted simultaneously, at different modes, in a single waveguide. Wavelength-division multiplexing (WDM), non-orthogonal multiple access (NOMA) and orthogonal-frequency-division multiplexing (OFDM) can also be utilized to further increase the optical interconnect capacity. In SiPh integrated circuits, waveguide bends are usually inevitable. However, for an MDM system with a multimode bus waveguide, the modal fields will become asymmetric when the waveguide bend is sharp. This will introduce inter-mode coupling and inter-mode crosstalk. One simple approach to achieve sharp bends in multimode bus waveguide is to use a Euler curve. Although it has been reported in the literature that sharp bends based on a Euler curve allow high performance and low inter-mode crosstalk multimode transmissions, we discover, by simulation and experiment, that the transmission performance between two Euler bends is length dependent, particularly when the bends are sharp. We investigate the length dependency of the straight multimode bus waveguide between two Euler bends. High transmission performance can be achieved by a proper design of the waveguide length, width, and bend radius. By using the optimized MDM bus waveguide length with sharp Euler bends, proof-of-concept NOMA-OFDM experimental transmissions, supporting two MDM modes and two NOMA users, are performed.
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BACKGROUND: The concept of career identity is integral to nursing practices and forms the basis of the nursing professions. Positive career identity is essential for providing high-quality care, optimizing patient outcomes, and enhancing the retention of health professionals. Therefore, there is a need to explore potential influencing variables, thereby developing effective interventions to improve career identity. OBJECTIVES: To investigate the relationship between moral distress, moral courage, and career identity, and explore the mediating role of moral courage between moral distress and career identity among nurses. DESIGN: A quantitative, cross-sectional study. METHODS: A convenient sample of 800 nurses was recruited from two tertiary care hospitals between February and March 2022. Participants were assessed using the Moral Distress Scale-revised, Nurses' Moral Courage Scale, and Nursing Career Identity Scale. This study was described in accordance with the STROBE statement. ETHICAL CONSIDERATION: Research ethics approval was obtained from the researcher's university and hospital where this study was conducted prior to data collection. FINDINGS: Moral distress is negatively associated while moral courage is positively associated with career identity among nurses. Moral courage partially mediates the relationship between moral distress and career identity (ß = -0.230 to -0.163, p < 0.01). DISCUSSION: The findings reveal a relationship between moral distress, moral courage, and career identity among nurses. CONCLUSION: By paying attention to nurses' moral distress and courage, healthcare providers can contribute to the development of effective interventions to improve career identity, and subsequently performance, among nurses.
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Coragem , Enfermeiras e Enfermeiros , Humanos , Estudos Transversais , Princípios Morais , Pessoal de Saúde , Inquéritos e QuestionáriosRESUMO
The NS1 protein of the influenza A virus plays a critical role in regulating several biological processes in cells, including the type I interferon (IFN) response. We previously profiled the cellular factors that interact with the NS1 protein of influenza A virus and found that the NS1 protein interacts with proteins involved in RNA splicing/processing, cell cycle regulation, and protein targeting processes, including 14-3-3ε. Since 14-3-3ε plays an important role in retinoic acid-inducible gene I (RIG-I) translocation to mitochondrial antiviral-signaling protein (MAVS) to activate type I IFN expression, the interaction of the NS1 and 14-3-3ε proteins may prevent the RIG-I-mediated IFN response. In this study, we confirmed that the 14-3-3ε protein interacts with the N-terminal domain of the NS1 protein and that the NS1 protein inhibits RIG-I-mediated IFN-ß promoter activation in 14-3-3ε-overexpressing cells. In addition, our results showed that knocking down 14-3-3ε can reduce IFN-ß expression elicited by influenza A virus and enhance viral replication. Furthermore, we found that threonine in the 49th amino acid position of the NS1 protein plays a role in the interaction with 14-3-3ε. Influenza A virus expressing C terminus-truncated NS1 with a T49A mutation dramatically increases IFN-ß mRNA in infected cells and causes slower replication than that of virus without the T-to-A mutation. Collectively, this study demonstrates that 14-3-3ε is involved in influenza A virus-initiated IFN-ß expression and that the interaction of the NS1 protein and 14-3-3ε may be one of the mechanisms for inhibiting type I IFN activation during influenza A virus infection. IMPORTANCE Influenza A virus is an important human pathogen causing severe respiratory disease. The virus has evolved several strategies to dysregulate the innate immune response and facilitate its replication. We demonstrate that the NS1 protein of influenza A virus interacts with the cellular chaperone protein 14-3-3ε, which plays a critical role in retinoic acid-inducible gene I (RIG-I) translocation that induces type I interferon (IFN) expression, and that NS1 protein prevents RIG-I translocation to the mitochondrial membrane. The interaction site for 14-3-3ε is the RNA-binding domain (RBD) of the NS1 protein. Therefore, this research elucidates a novel mechanism by which the NS1 RBD mediates IFN-ß suppression to facilitate influenza A viral replication. Additionally, the findings reveal the antiviral role of 14-3-3ε during influenza A virus infection.
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Proteínas 14-3-3/imunologia , Influenza Humana/imunologia , Interferon beta/metabolismo , Proteínas 14-3-3/metabolismo , Linhagem Celular Tumoral , Proteína DEAD-box 58/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata/imunologia , Vírus da Influenza A/metabolismo , Influenza Humana/metabolismo , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Interferon beta/fisiologia , Regiões Promotoras Genéticas/genética , Processamento de Proteína Pós-Traducional , RNA Viral/genética , Receptores Imunológicos/metabolismo , Proteínas não Estruturais Virais/imunologia , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/genéticaRESUMO
BACKGROUND AND AIMS: The mechanisms by which the I148M mutant variant of the patatin-like phospholipase domain-containing 3 (PNPLA3I148M ) drives development of nonalcoholic steatohepatitis (NASH) are not known. The aim of this study was to obtain insights on mechanisms underlying PNPLA3I148M -induced acceleration of NASH. APPROACH AND RESULTS: Hepatocyte-specific overexpression of empty vector (luciferase), human wild-type PNPLA3, or PNPLA3I148M was achieved using adeno-associated virus 8 in a diet-induced mouse model of nonalcoholic fatty liver disease followed by chow diet or high-fat Western diet with ad libitum administration of sugar in drinking water (WDSW) for 8 weeks. Under WDSW, PNPLA3I148M overexpression accelerated steatohepatitis with increased steatosis, inflammation ballooning, and fibrosis (P < 0.001 versus other groups for all). Silencing PNPLA3I148M after its initial overexpression abrogated these findings. PNPLA3I148M caused 22:6n3 docosahexanoic acid depletion and increased ceramides under WDSW in addition to increasing triglycerides and diglycerides, especially enriched with unsaturated fatty acids. It also increased oxidative stress and endoplasmic reticulum stress. Increased total ceramides was associated with signature of transducer and activator of transcription 3 (STAT3) activation with downstream activation of multiple immune-inflammatory pathways at a transcriptomic level by network analyses. Silencing PNPLA3I148M reversed STAT3 activation. Conditioned media from HepG2 cells overexpressing PNPLA3I148M increased procollagen mRNA expression in LX2 cells; this was abrogated by hepatocyte STAT3 inhibition. CONCLUSIONS: Under WDSW, PNPLA3I148M overexpression promotes steatosis and NASH by metabolic reprogramming characterized by increased triglycerides and diglycerides, n3 polyunsaturated fatty acid depletion, and increased ceramides with resultant STAT3 phosphorylation and downstream inflammatory pathway activation driving increased stellate cell fibrogenic activity.
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Lipase , Cirrose Hepática , Proteínas de Membrana , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica/efeitos adversos , Dieta Ocidental/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Expressão Gênica , Células Hep G2 , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Humanos , Lipase/genética , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Polimorfismo Genético , TranscriptomaRESUMO
Synovial macrophage polarization and inflammation are essential for osteoarthritis (OA) development, yet the molecular mechanisms and regulation responsible for the pathogenesis are still poorly understood. Here, we report that pseudolaric acid B (PAB) attenuated articular cartilage degeneration and synovitis during OA. PAB, a diterpene acid, specifically inhibited NF-κB signalling and reduced the production of pro-inflammatory cytokines, which further decreased M1 polarization and vessel formation. We further provide in vivo and in vitro evidences that PAB suppressed NF-κB signalling by stabilizing PPARγ. Using PPARγ antagonist could abolish anti-inflammatory effect of PAB and rescue the activation of NF-κB signalling during OA. Our findings identify a previously unrecognized role of PAB in the regulation of OA and provide mechanisms by which PAB regulates NF-κB signalling through PPARγ, which further suggest targeting synovial inflammation or inhibiting vessel formation at early stage could be an effective preventive strategy for OA.
Assuntos
Diterpenos/farmacologia , Osteoartrite/tratamento farmacológico , PPAR gama/genética , Sinovite/tratamento farmacológico , Animais , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/crescimento & desenvolvimento , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/crescimento & desenvolvimento , Cartilagem Articular/patologia , Condrócitos/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Inflamação/tratamento farmacológico , Inflamação/genética , Inflamação/parasitologia , Camundongos , NF-kappa B/genética , Osteoartrite/genética , Osteoartrite/patologia , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Sinovite/genética , Sinovite/patologia , Fator de Transcrição RelA/genéticaRESUMO
Dihydroorotase (DHOase) is the third enzyme in the de novo biosynthesis pathway of pyrimidine nucleotides and considered an attractive target for potential antimalarial, anticancer, and antipathogen chemotherapy. Whether the FDA-approved clinical drug 5-fluorouracil (5-FU) that is used to target the enzyme thymidylate synthase for anticancer therapy can also bind to DHOase remains unknown. Here, we report the crystal structures of DHOase from Saccharomyces cerevisiae (ScDHOase) complexed with malate, 5-FU, and 5-aminouracil (5-AU). ScDHOase shares structural similarity with Escherichia coli DHOase. We also characterized the binding of 5-FU and 5-AU to ScDHOase by using the fluorescence quenching method. These complexed structures revealed that residues Arg18, Asn43, Thr106, and Ala275 of ScDHOase were involved in the 5-FU (PDB entry 6L0B) and 5-AU binding (PDB entry 6L0F). Overall, these results provide structural insights that may facilitate the development of new inhibitors targeting DHOase and constitute the 5-FU and 5-AU interactomes for further clinical chemotherapies.