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S-nitrosylation, the oxidative modification of Cys residues by nitric oxide (NO) to form S-nitrosothiols (SNOs), modifies all main classes of proteins and provides a fundamental redox-based cellular signaling mechanism. However, in contrast to other post-translational protein modifications, S-nitrosylation is generally considered to be non-enzymatic, involving multiple chemical routes. We report here that endogenous protein S-nitrosylation in the model organism E. coli depends principally upon the enzymatic activity of the hybrid cluster protein Hcp, employing NO produced by nitrate reductase. Anaerobiosis on nitrate induces both Hcp and nitrate reductase, thereby resulting in the S-nitrosylation-dependent assembly of a large interactome including enzymes that generate NO (NO synthase), synthesize SNO-proteins (SNO synthase), and propagate SNO-based signaling (trans-nitrosylases) to regulate cell motility and metabolism. Thus, protein S-nitrosylation by NO in E. coli is essentially enzymatic, and the potential generality of the multiplex enzymatic mechanism that we describe may support a re-conceptualization of NO-based cellular signaling.
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Nitrosação/fisiologia , S-Nitrosotióis/metabolismo , Cisteína/metabolismo , Escherichia coli , Proteínas de Escherichia coli , Óxido Nítrico/metabolismo , Oxirredução , Processamento de Proteína Pós-Traducional/fisiologia , Proteínas/metabolismo , Proteólise , Proteômica/métodos , Transdução de SinaisRESUMO
OBJECTIVES: We aimed to characterize and investigate the safety and efficacy of Plonmarlimab, a novel anti-granulocyte-macrophage colony-stimulating factor (anti-GM-CSF) neutralizing antibody, on the treatment of macrophage activation syndrome (MAS), a life-threatening systemic inflammatory disease, in pre-clinical models. METHODS: The binding affinity was evaluated using Biacore. The neutralizing activity was measured through the blockade of ligand-receptor interaction, inhibition of STAT5 phosphorylation and suppression of TF-1 cell proliferation. The efficacy of Plonmarlimab was evaluated in a humanized MAS model, which was established by engrafting human umbilical cord blood (UCB) cells into NOG-EXL mice. Additionally, the safety profile of Plonmarlimab was investigated in cynomolgus monkeys. RESULTS: At the molecular level, Plonmarlimab showed sub-nanomolar binding affinity with human GM-CSF and effectively blocked the binding of GM-CSF to its receptor. At the cellular level, Plonmarlimab dose-dependently inhibited intracellular STAT5 phosphorylation and suppressed GM-CSF-induced TF-1 proliferation. In the UCB-engrafted NOG-EXL MAS mouse model, Plonmarlimab treatment significantly ameliorated disease progression, demonstrated by the improvements in body weight loss, anaemia and some histopathological features. Furthermore, Plonmarlimab was well tolerated up to 150 mg/kg weekly in monkeys with no reported adverse effects. CONCLUSIONS: Plonmarlimab is a highly potent GM-CSF blocking antibody and has demonstrated promising efficacy in a pre-clinical MAS model with a favourable safety profile, supporting its clinical development.
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BACKGROUND: The concentrations of linezolid, its optimal regimen and the associated side effects in elderly patients remain unclear. METHODS: In this multicentre, prospective study, elderly patients receiving linezolid at four tertiary hospitals in Beijing between May 2021 and December 2022 were included. Linezolid concentrations and haematological toxicity were monitored dynamically. Risk factors for linezolid overexposure and moderate-to-severe linezolid-induced thrombocytopenia (M/S LIT) were analysed, and a predictive model of M/S LIT was developed. RESULTS: A total of 860 linezolid concentrations were measured in 313 patients. The median trough concentrations of linezolid were 24.4 (15.3, 35.8) mg/L at 36-72â h and 26.1 (17.0, 38.1) mg/L at 5-10â days (Pâ=â0.132). Severe linezolid exposure was independently associated with age, estimated glomerular filtration rate (eGFR) and the worst SOFA score (SOFA1), and we further recommended dose regimens for elderly patients based on these findings. The incidences of linezolid-induced thrombocytopenia(LIT) and M/S LIT were 73.5% and 47.6%, respectively. M/S LIT was independently correlated with treatment duration, average trough concentration (TDMa), baseline platelet count, eGFR and baseline SOFA score (SOFA0). The developed nomogram predicted M/S LIT with an area under the curve of 0.767 (95% CI 0.715-0.820), a sensitivity of 71.1% and a specificity of 73.2%. CONCLUSIONS: Linezolid trough concentrations increased dramatically in the elderly, by about 10â mg/L in patients aged 65-80â years, followed by a further increase of 10â mg/L for every 10â years of age. Therapeutic drug monitoring is recommended in elderly patients receiving linezolid. The developed nomogram may predict M/S LIT and guide dosage adjustments of linezolid. Clinical trial registration number: ChiCTR2100045707.
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Antibacterianos , Monitoramento de Medicamentos , Linezolida , Nomogramas , Trombocitopenia , Humanos , Linezolida/efeitos adversos , Linezolida/farmacocinética , Linezolida/administração & dosagem , Idoso , Masculino , Feminino , Estudos Prospectivos , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Antibacterianos/administração & dosagem , Trombocitopenia/induzido quimicamente , Idoso de 80 Anos ou mais , Fatores de Risco , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: In this study, we describe the patterns of antibiotic prescription for neonates based on World Health Organization's (WHO) Essential Medicines List Access, Watch, and Reserve (AWaRe), and the Management of Antibiotic Classification (MAC) Guidelines in China. METHODS: One-day point-prevalence surveys (PPS) on antimicrobial prescriptions were conducted on behalf of hospitalized neonates in China from September 1 and November 30, annually from 2017 to 2019. RESULTS: Data was collected for a total of 2674 neonatal patients from 15 hospitals in 9 provinces across China of which 1520 were newborns who received at least one antibiotic agent. A total of 1943 antibiotic prescriptions were included in the analysis. The most commonly prescribed antibiotic was meropenem (11.8%). The most common reason for prescribing antibiotic to neonates was pneumonia (44.2%). There were 419 (21.6%), 1343 (69.1%) and 6 (0.3%) antibiotic prescriptions in the Access, Watch and Reserve groups, respectively. According to MAC Guidelines in China, there were 1090 (56.1%) antibiotic agents in the Restricted and 414 (21.3%) in the Special group. CONCLUSION: Broad-spectrum antibiotics included in the Watch and Special groups were likely to be overused in Chinese neonates.
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Antibacterianos , Prescrições de Medicamentos , Humanos , Recém-Nascido , Prevalência , Pesquisas sobre Atenção à Saúde , Antibacterianos/uso terapêutico , China/epidemiologiaRESUMO
The GRIN genes encoding N-methyl-D-aspartate receptor (NMDAR) subunits are remarkably intolerant to variation. Many pathogenic NMDAR variants result in their protein misfolding, inefficient assembly, reduced surface expression, and impaired function on neuronal membrane, causing neurological disorders including epilepsy and intellectual disability. Here, we investigated the proteostasis maintenance of NMDARs containing epilepsy-associated variations in the GluN2A subunit, including M705V and A727T. In the transfected HEK293T cells, we showed that the two variants were targeted to the proteasome for degradation and had reduced functional surface expression. We demonstrated that the application of BIX, a known small molecule activator of an HSP70 family chaperone BiP (binding immunoglobulin protein) in the endoplasmic reticulum (ER), dose-dependently enhanced the functional surface expression of the M705V and A727T variants in HEK293T cells. Moreover, BIX (10 µM) increased the surface protein levels of the M705V variant in human iPSC-derived neurons. We revealed that BIX promoted folding, inhibited degradation, and enhanced anterograde trafficking of the M705V variant by modest activation of the IRE1 pathway of the unfolded protein response. Our results suggest that adapting the ER proteostasis network restores the folding, trafficking, and function of pathogenic NMDAR variants, representing a potential treatment for neurological disorders resulting from NMDAR dysfunction.
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Epilepsia , Receptores de N-Metil-D-Aspartato , Humanos , Receptores de N-Metil-D-Aspartato/metabolismo , Proteostase , Células HEK293 , Epilepsia/genética , Epilepsia/metabolismo , Retículo Endoplasmático/metabolismoRESUMO
BACKGROUND: Corpus callosum glioblastoma (ccGBM) is a specific type of GBM and has worse outcomes than other non-ccGBMs. We sought to identify whether en-bloc resection of ccGBMs based on T2-FLAIR imaging contributes to clinical outcomes and can achieve a satisfactory balance between maximal resection and preservation of neurological function. METHODS: A total of 106 adult ccGBM patients (including astrocytoma, WHO grade 4, IDH mutation, and glioblastoma) were obtained from the Department of Neurosurgery in Nanfang Hospital between January 2008 and December 2018. The clinical data, including gender, age, symptoms, location of tumor, involvement of eloquent areas, extent of resection (EOR), pre- and postoperative Karnofsky Performance Status (KPS) scales, and National Institute of Health stroke scale (NIHSS) scores were collected. Propensity score matching (PSM) analysis was applied to control the confounders for analyzing the relationship between the en-bloc technique and EOR, and the change in the postoperative KPS scales and NIHSS scores. RESULTS: Applying the en-bloc technique did not negatively affect the postoperative KPS scales compared to no-en-bloc resection (P = 0.851 for PSM analysis) but had a positive effect on preserving or improving the postoperative NIHSS scores (P = 0.004 for PSM analysis). A positive correlation between EOR and the en-bloc technique was identified (r = 0.483, P < 0.001; r = 0.720, P < 0.001 for PSM analysis), indicating that applying the en-bloc technique could contribute to enlarged maximal resection. Further survival analysis confirmed that applying the en-bloc technique and achieving supramaximal resection could significantly prolong OS and PFS, and multivariate analysis suggested that tumor location, pathology, EOR and the en-bloc technique could be regarded as independent prognostic indicators for OS in patients with ccGBMs, and pathology, EOR and the en-bloc technique were independently correlated with patient's PFS. Interestingly, the en-bloc technique also provided a marked reduction in the risk of tumor recurrence compared with the no-en-bloc technique in tumors undergoing TR, indicating that the essential role of the en-bloc technique in ccGBM surgery (HR: 0.712; 95% CI: 0.535-0.947; P = 0.02). CONCLUSIONS: The en-bloc technique could contribute to achieving an enlarged maximal resection and could significantly prolong overall survival and progression-free survival in patients with ccGBMs.
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Neoplasias Encefálicas , Glioblastoma , Adulto , Humanos , Glioblastoma/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Corpo Caloso/cirurgia , Corpo Caloso/patologia , Neoplasias Encefálicas/cirurgia , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Procedimentos Neurocirúrgicos/métodosRESUMO
A novel multistatic integrated sensing and communication (ISAC) system based on macro-micro cooperation for the sixth-generation (6G) mobile network is proposed. Instead of using macrosites at both the transmitter and receiver sides, microsites are considered as receivers in cooperative sensing. This system is important since microsites can be deployed more flexibly to reduce their distances to the sensing objects, providing better coverage for sensing service. In this work, we first analyze the deployment problem of microsites, which can be deployed along the radius and azimuth angle to cover macrosite cells. The coverage area of each microsite is derived in terms of its position in the cell. Then, we describe an efficient estimating approach for obtaining the position and velocity of sensing objects in the macrosite cell. By choosing multiple microsites around the targeted sensing area, joint data processing with an efficient optimization method is also provided. Simulation results show that the multistatic ISAC system employing macro-micro cooperation can improve the position and velocity estimation accuracy of objects compared to systems employing macrosite cooperation alone, demonstrating the effectiveness and potential for implementing the proposed system in the 6G mobile network.
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BACKGROUND: Newly graduated registered nurses leaving the nursing profession in the early stages of their career have enormous financial and time implications for nursing organizations and affect the quality of nursing care. OBJECTIVE: To identify the factors influencing newly graduated registered nurses' intention to leave the nursing profession over the past 10 years. METHODS: The framework developed by Whittemore and Knafl was used to conduct this integrative review. An electronic search was conducted for English articles to identify research studies published between 2011-2022 using the following databases of PubMed, MEDLINE, CINAHL, PsycINFO, and Scopus. Eligible publications were critically reviewed and scored using the Critical Appraisal Skills Program Checklist and the Center for Evidence-Based Management appraisal. RESULTS: Twenty-one studies were analyzed. The main factors affecting newly graduated registered nurses' intention to leave the nursing profession included demographic factors (age, educational level, year of experience, professional title, employment status, health status, shift, hospital location and size), supervisor and peer support, challenges in the workplace, cognitive and affective response to work, work environment (collegial nurse-physician relations, insufficient staffing level, person-work environment fit), gender stereotypes, autonomous motivation, role models, and resilience. CONCLUSIONS: The factors affecting newly graduated registered nurses' intention to leave the nursing profession are multifaceted and should receive continuous attention from nurse managers. The findings provide more comprehensive for nurse administrators to develop intervention strategies to mitigate newly graduated registered nurses' turnover intention.
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BACKGROUND: The study aimed to investigate anatomical changes in the neck region and evaluate their impact on dose distribution in patients with nasopharyngeal carcinoma (NPC) undergoing intensity modulated radiation therapy (IMRT). Additionally, the study sought to determine the optimal time for replanning during the course of treatment. METHODS: Twenty patients diagnosed with NPC underwent IMRT, with weekly pretreatment kV fan beam computed tomography (FBCT) scans in the treatment room. Metastasized lymph nodes in the neck region and organs at risk (OARs) were redelineation using the images from the FBCT scans. Subsequently, the original treatment plan (PLAN0) was replicated to each FBCT scan to generate new plans labeled as PLAN 1-6. The dose-volume histograms (DVH) of the new plans and the original plan were compared. One-way repeated measure ANOVA was utilized to establish threshold(s) at various time points. The presence of such threshold(s) would signify significant change(s), suggesting the need for replanning. RESULTS: Progressive volume reductions were observed over time in the neck region, the gross target volume for metastatic lymph nodes (GTVnd), as well as the submandibular glands and parotids. Compared to PLAN0, the mean dose (Dmean) of GTVnd-L significantly increased in PLAN5, while the minimum dose covering 95% of the volume (D95%) of PGTVnd-L showed a significant decrease from PLAN3 to PLAN6. Similarly, the Dmean of GTVnd-R significantly increased from PLAN4 to PLAN6, whereas the D95% of PGTVnd-R exhibited a significant decrease during the same period. Furthermore, the dose of bilateral parotid glands, bilateral submandibular glands, brainstem and spinal cord was gradually increased in the middle and late period of treatment. CONCLUSION: Significant anatomical and dosimetric changes were noted in both the target volumes and OARs. Considering the thresholds identified, it is imperative to undertake replanning at approximately 20 fractions. This measure ensures the delivery of adequate doses to target volumes while mitigating the risk of overdosing on OARs.
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Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Pescoço , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/patologia , Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/diagnóstico por imagem , Pescoço/diagnóstico por imagem , Masculino , Radioterapia de Intensidade Modulada/métodos , Pessoa de Meia-Idade , Feminino , Adulto , Tomografia Computadorizada por Raios X/métodos , Carcinoma/diagnóstico por imagem , Carcinoma/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Órgãos em Risco/efeitos da radiação , Órgãos em Risco/diagnóstico por imagem , Radiometria/métodosRESUMO
In recent years, the number of premature births worldwide has been increasing, and their long-term prognoses, particularly the cardiovascular outcomes of preterm individuals in adulthood, have become a growing concern. Adults who were born prematurely are at a higher risk for cardiovascular diseases, which may be related to changes in cardiovascular structure, renal structure alterations, changes in body composition, and overactivation of the hypothalamic-pituitary-adrenal axis. To improve the outcomes for preterm individuals, long-term follow-up monitoring and effective prevention and treatment measures are necessary. This article aims to review the relevant literature, summarize the risks and mechanisms of hypertension during childhood and adulthood in those born prematurely, and enhance awareness and understanding of the risk of hypertension in adults who were born prematurely.
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Hipertensão , Nascimento Prematuro , Humanos , Hipertensão/etiologia , Hipertensão/fisiopatologia , Nascimento Prematuro/etiologia , Recém-NascidoRESUMO
Gamma-aminobutyric acid type A (GABAA) receptors are the primary inhibitory neurotransmitter-gated ion channels in the mammalian central nervous system. Maintenance of GABAA receptor protein homeostasis (proteostasis) in cells utilizing its interacting proteins is essential for the function of GABAA receptors. However, how the proteostasis network orchestrates GABAA receptor biogenesis in the endoplasmic reticulum is not well understood. Here, we employed a proteomics-based approach to systematically identify the interactomes of GABAA receptors. We carried out a quantitative immunoprecipitation-tandem mass spectrometry analysis utilizing stable isotope labeling by amino acids in cell culture. Furthermore, we performed comparative proteomics by using both WT α1 subunit and a misfolding-prone α1 subunit carrying the A322D variant as the bait proteins. We identified 125 interactors for WT α1-containing receptors, 105 proteins for α1(A322D)-containing receptors, and 54 overlapping proteins within these two interactomes. Our bioinformatics analysis identified potential GABAA receptor proteostasis network components, including chaperones, folding enzymes, trafficking factors, and degradation factors, and we assembled a model of their potential involvement in the cellular folding, degradation, and trafficking pathways for GABAA receptors. In addition, we verified endogenous interactions between α1 subunits and selected interactors by using coimmunoprecipitation in mouse brain homogenates. Moreover, we showed that TRIM21 (tripartite motif containing-21), an E3 ubiquitin ligase, positively regulated the degradation of misfolding-prone α1(A322D) subunits selectively. This study paves the way for understanding the molecular mechanisms as well as fine-tuning of GABAA receptor proteostasis to ameliorate related neurological diseases such as epilepsy.
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Proteostase , Receptores de GABA-A , Animais , Camundongos , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Ácido gama-Aminobutírico/metabolismo , Proteômica , Receptores de GABA-A/metabolismoRESUMO
Antiplatelet therapy (APT) plays an important role in the prevention of ischaemic stroke (IS). Our aim was to assess the influence of short-term single APT (SAPT) and dual APT (DAPT) on the prognosis of patients with acute IS with and without cerebral microbleeds (CMBs). We conducted a single-centre, retrospective, observational cohort study of patients with acute IS who underwent susceptibility-weighted imaging (SWI) to determine the presence of CMBs between January 2015 and December 2020. The patients were treated with either DAPT or SAPT and followed up for at least 2 years. The primary endpoint was a composite of recurrent IS and intracerebral haemorrhage (ICH), while either recurrent IS or ICH was considered as other endpoints. We computed weighted Kaplan-Meier curves and identified risk factors using the Cox proportional hazards model. Among the 581 enrolled patients, those with CMBs (n = 225; P = 0.004) had a higher risk of the primary endpoint than those without CMBs (n = 356), especially higher risk of recurrent IS (P = 0.029). In the SAPT group, the presence of CMBs increased the risk of the primary endpoint (P = 0.013), especially that of recurrent IS (P = 0.019). In the DAPT group, the occurrence of ICH was higher in patients with CMBs (P = 0.031). The CMB distribution did not influence the risk of recurrent IS or ICH. In patients with acute IS and CMBs, DAPT may offset the risk of recurrent IS due to CMBs but increase the risk of ICH.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Inibidores da Agregação Plaquetária/efeitos adversos , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Estudos Retrospectivos , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/induzido quimicamente , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/induzido quimicamente , Fatores de Risco , Imageamento por Ressonância MagnéticaRESUMO
The recombination activating gene 1 (RAG1) is essential for V(D)J recombination during T- and B-cell development. In this study, we presented a case study of a 41-day-old female infant who exhibited symptoms of generalized erythroderma, lymphadenopathy, hepatosplenomegaly, and recurrent infections including suppurative meningitis and septicemia. The patient showed a T+B-NK+ immunophenotype. We observed an impaired thymic output, as indicated by reduced levels of naive T cells and sjTRECs, coupled with a restricted TCR repertoire. Additionally, T-cell CFSE proliferation was impaired, indicating a suboptimal T-cell response. Notably, our data further revealed that T cells were in an activated state. Genetic analysis revealed a previously reported compound heterozygous mutation (c. 1186C > T, p. R396C; c. 1210C > T, p. R404W) in the RAG1 gene. Structural analysis of RAG1 suggested that the R396C mutation might lead to the loss of hydrogen bonds with neighboring amino acids. These findings contribute to our understanding of RAG1 deficiency and may have implications for the development of novel therapies for patients with this condition.
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Proteínas de Homeodomínio , Imunodeficiência Combinada Severa , Feminino , Humanos , Lactente , Genes RAG-1 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Mutação , Imunodeficiência Combinada Severa/genética , Linfócitos TRESUMO
Rabies, caused by the rabies virus (RABV), is the most fatal zoonotic disease. It is a neglected tropical disease which remains a major public health problem, causing approximately 59,000 deaths worldwide annually. Despite the existence of effective vaccines, the high incidence of human rabies is mainly linked to tedious vaccine immunisation procedures and the overall high cost of post-exposure prophylaxis. Therefore, it is necessary to develop an effective vaccine that has a simple procedure and is affordable to prevent rabies infection in humans. RABV belongs to the genus Lyssavirus and family Rhabdoviridae. Previous phylogenetic analyses have identified seven major clades of RABV in China (China I-VII), confirmed by analysing nucleotide sequences from both the G and N proteins. This study evaluated the immunogenicity and protective capacity of SYS6008, an mRNA rabies vaccine expressing rabies virus glycoprotein, in mice and cynomolgus macaques. We demonstrated that SYS6008 induced sufficient levels of rabies neutralising antibody (RVNA) in mice. In addition, SYS6008 elicited strong and durable RVNA responses in vaccinated cynomolgus macaques. In the pre-exposure prophylaxis murine model, one or two injections of SYS6008 at 1/10 or 1/30 of dosage provided protection against a challenge with a 30-fold LD50 of rabies virus (China I and II clades). We also demonstrated that in the post-exposure prophylaxis murine model, which was exposed to lethal rabies virus (China I-VII clades) before vaccination, one or two injections of SYS6008 at both 1/10 and 1/30 dosages provided better protection against rabies virus challenge than the immunization by five injections of commercial vaccines at the same dosage. In addition, we proved that SYS6008-induced RVNAs could neutralise RABV from the China I-VII clades. Finally, 1/10 of the dosage of SYS6008 was able to stimulate significant RABV-G specificity in the T cell response. Furthermore, we found that SYS6008 induced high cellular immunity, including RABV-G-specific T cell responses and memory B cells. Our results imply that the SYS6008 rabies vaccine, with a much simpler vaccination procedure, better immunogenicity, and enhanced protective capacity, could be a candidate vaccine for post-exposure prophylaxis of rabies infections.
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Vacina Antirrábica , Vírus da Raiva , Raiva , Humanos , Animais , Camundongos , Raiva/prevenção & controle , Vacina Antirrábica/genética , Vírus da Raiva/genética , Profilaxia Pós-Exposição/métodos , Modelos Animais de Doenças , Filogenia , Anticorpos Antivirais , MacacaRESUMO
BACKGROUND: Pituitary adenylate cyclase-activating polypeptide (PACAP) is a multipotent neuropeptide widely distributed in the trigeminovascular system (TVS) and higher brain regions. At present, the underlying mechanism of PACAP/PACAP type1 (PAC1) receptor in migraine generation remains unclear. METHODS: The rat model of chronic migraine (CM) was established by repeated intraperitoneal injection of nitroglycerin (NTG). Von Frey filaments and hot plate tests were used to measure the mechanical and thermal thresholds. The expression levels of c-Fos, calcitonin gene-related peptide (CGRP), PACAP, PAC1, protein kinase A (PKA) and phosphorylated extracellular signal-regulated kinase (ERK) were assessed by western blotting or immunofluorescence staining. The internalization of PAC1 receptor was visualized by fluorescence microscope and laser scanning confocal microscope. RESULTS: The results showed that c-Fos and CGRP expression significantly increased after repeated administrations of NTG or PACAP. Pitstop2 notably improved hyperalgesia in CM rats, while PACAP6-38 offered no benefit. In addition, PACAP-induced PAC1 receptor internalization, PKA and ERK pathways activation were blocked by Pitstop2 instead of PACAP6-38. CONCLUSIONS: Our results demonstrate that inhibition of PAC1 receptor internalization could effectively improve allodynia in CM rats by restraining ERK signaling pathway activation in a chronic migraine rat model. Modulation of receptor internalization may be a novel perspective to explore specific mechanisms of PACAP signaling activation in the trigeminal vascular system.
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Transtornos de Enxaqueca , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Ratos , Animais , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , MAP Quinases Reguladas por Sinal Extracelular , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Hiperalgesia , Sistema de Sinalização das MAP Quinases , Peptídeo Relacionado com Gene de Calcitonina/metabolismoRESUMO
BACKGROUND: Retinopathy of prematurity (ROP) is the leading cause of blindness in infants, and elevation of HIF-1α through the PI3K/Akt and ERK pathways is implicated in ROP pathogenesis. The mechanism of action of propranolol in ROP remains controversial. We investigated the effect of propranolol on ROP and explored its potential mechanisms of action in an oxygen-induced retinopathy (OIR) mouse model. METHODS: OIR mice were first treated with propranolol intraperitoneally, and the retina integrity was measured by FITC-dextran and hematoxylin-eosin staining. The expression of HIF-1α, VEGF, and key signaling pathway proteins was determined using real-time PCR and western blotting. RESULTS: FITC-dextran staining showed that propranolol treatment reduced damage to retinal morphology in OIR mice. Mice treated with propranolol showed a reduced number of nuclei of vascular endothelial cells penetrating the inner limiting membrane of the retina, confirming the therapeutic effect of propranolol on ROP. Further analysis showed that HIF-1α and PI3K/Akt/ERK pathway protein levels were significantly elevated in OIR mice. In contrast, propranolol treatment downregulated the expression of these proteins, indicating that the PI3K/Akt/ERK/HIF-1α axis is associated with propranolol-induced ROP alleviation. CONCLUSIONS: Propranolol has a therapeutic function against ROP, likely through the downregulation of HIF-1α via the PI3K/Akt/ERK pathway. IMPACT: Propranolol can reduce the formation of abnormal retinal neovascularization in oxygen-induced retinopathy (OIR) models, and reduce leaking, tortuous, and abnormally expanding retinal blood vessels. Propranolol possibly improves OIR by inhibiting the activated ERK and HIF-1α pathways. Furthermore, propranolol may downregulate HIF-1α via the PI3K/Akt/ERK pathway to ameliorate retinopathy of prematurity. This study elucidated that the therapeutic effect of propranolol in OIR mice does not involve the VEGFR-2 pathway.
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Neovascularização Retiniana , Retinopatia da Prematuridade , Humanos , Recém-Nascido , Animais , Camundongos , Propranolol/uso terapêutico , Retinopatia da Prematuridade/tratamento farmacológico , Retinopatia da Prematuridade/patologia , Sistema de Sinalização das MAP Quinases , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Células Endoteliais/metabolismo , Neovascularização Retiniana/metabolismo , Oxigênio/uso terapêutico , Camundongos Endogâmicos C57BL , Modelos Animais de DoençasRESUMO
Neonatal invasive candidiasis (NIC) has significant morbidity and mortality. Reports have shown a different profile of those neonates affected with NIC and of fluconazole-resistant Candida spp. isolates in low- and middle-income countries (LMICs) compared to high-income countries (HICs). We describe the epidemiology, Candida spp. distribution, treatment, and outcomes of neonates with NIC from LMICs enrolled in a global, prospective, longitudinal, observational cohort study (NeoOBS) of hospitalized infants <60 days postnatal age with sepsis (August 2018-February 2021). A total of 127 neonates from 14 hospitals in 8 countries with Candida spp. isolated from blood culture were included. Median gestational age of affected neonates was 30 weeks (IQR: 28-34), and median birth weight was 1270 gr (interquartile range [IQR]: 990-1692). Only a minority had high-risk criteria, such as being born <28 weeks, 19% (24/127), or birth weight <1000 gr, 27% (34/127). The most common Candida species were C. albicans (n = 45, 35%), C. parapsilosis (n = 38, 30%), and Candida auris (n = 18, 14%). The majority of C. albicans isolates were fluconazole susceptible, whereas 59% of C. parapsilosis isolates were fluconazole-resistant. Amphotericin B was the most common antifungal used [74% (78/105)], followed by fluconazole [22% (23/105)]. Death by day 28 post-enrollment was 22% (28/127). To our knowledge, this is the largest multi-country cohort of NIC in LMICs. Most of the neonates would not have been considered at high risk for NIC in HICs. A substantial proportion of isolates was resistant to first choice fluconazole. Understanding the burden of NIC in LMIC is essential to guide future research and treatment guidelines.
Our study describes neonates from low- and middle-income countries with neonatal invasive candidiasis (NIC). Most of them were outside the groups considered at high risk for NIC described in high-income countries. Candida spp. epidemiology was also different. The mortality was high (22%). Further research in these settings is required.
Assuntos
Candidíase Invasiva , Fluconazol , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Peso ao Nascer , Candida , Candida albicans , Candida parapsilosis , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/epidemiologia , Candidíase Invasiva/microbiologia , Candidíase Invasiva/veterinária , Países em Desenvolvimento , Farmacorresistência Fúngica , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Testes de Sensibilidade Microbiana/veterinária , Estudos Prospectivos , Humanos , Recém-Nascido , LactenteRESUMO
OBJECTIVES: This study aimed to identify the related risk factors and potential predictors of SARS-CoV-2 RNA negative conversion by describing the dynamics of viral shedding in infected children admitted to two hospitals from Shanghai during the Omicron variant outbreak. METHODS: This retrospective cohort included laboratory-confirmed cases of SARS-CoV-2 infection from Shanghai between March 28 and May 31, 2022. Clinical characteristics, personal vaccination, and household vaccination rates were collected through electronic health records and telephone interviews. RESULTS: A total of 603 paediatric patients confirmed to have COVID-19 were included in this study. Both univariate and multivariate analyses were performed to filter independent factors for the duration to viral RNA negative conversion. Data on the redetection of SARS-CoV-2 in the patients after they showed negative results on the RTâPCR test (intermittent negative status) were also analysed. The median duration of virus shedding was 12 (interquartile range, IQR: 10-14) days. The severity of clinical outcome, personal vaccination-2doses, household vaccination rates, and abnormal defecation were factors indecently affecting negative conversion of SARS-CoV-2 RNA, suggesting that patients who had abnormal defecation or with more severe conditions would have delayed virological clearance, while patients who previously had 2 doses of vaccination or had higher household vaccination rates would have accelerated virological clearance. Loss of appetite (odds ratio (OR): 5.343; 95% CI: 3.307-8.632) and abnormal defecation (OR: 2.840; 95% CI: 1.736-4.645) were significantly associated with intermittent negative status. CONCLUSION: These findings could provide clues for the early identification of paediatric patients with prolonged viral shedding and could enrich the evidence for the development of prevention and control strategies, especially vaccination policies for children and adolescents.
Assuntos
COVID-19 , Dispepsia , Adolescente , Humanos , Criança , Criança Hospitalizada , RNA Viral/genética , SARS-CoV-2/genética , Estudos Retrospectivos , China/epidemiologia , COVID-19/epidemiologiaRESUMO
Loss-of-function diseases are often caused by a mutation in a protein traversing the secretory pathway that compromises the normal balance between protein folding, trafficking, and degradation. We demonstrate that the innate cellular protein homeostasis, or proteostasis, capacity can be enhanced to fold mutated enzymes that would otherwise misfold and be degraded, using small molecule proteostasis regulators. Two proteostasis regulators are reported that alter the composition of the proteostasis network in the endoplasmic reticulum through the unfolded protein response, increasing the mutant folded protein concentration that can engage the trafficking machinery, restoring function to two nonhomologous mutant enzymes associated with distinct lysosomal storage diseases. Coapplication of a pharmacologic chaperone and a proteostasis regulator exhibits synergy because of the former's ability to further increase the concentration of trafficking-competent mutant folded enzymes. It may be possible to ameliorate loss-of-function diseases by using proteostasis regulators alone or in combination with a pharmacologic chaperone.
Assuntos
Doenças por Armazenamento dos Lisossomos/metabolismo , Dobramento de Proteína , Proteínas/metabolismo , Linhagem Celular , Fibroblastos/metabolismo , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/metabolismo , Humanos , Leupeptinas/farmacologia , Doenças por Armazenamento dos Lisossomos/tratamento farmacológico , Chaperonas Moleculares/farmacologia , Triterpenos Pentacíclicos , Doença de Tay-Sachs/tratamento farmacológico , Doença de Tay-Sachs/metabolismo , Triterpenos/farmacologiaRESUMO
Cerebral microbleeds (CMBs) are commonly detected in the brains of patients with acute ischemic stroke (AIS). With the development of neuroimaging, clinicians are paying more attention to the presence of CMBs. CMBs were found to significantly increase the risk of intracranial hemorrhagic transformation and hemorrhage in patients with AIS, especially in patients with concurrent atrial fibrillation (AF). Additionally, the presence of CMBs is thought to be a symbol of a high risk of recurrent ischemic stroke (IS). A few researchers have found that the presence of CMBs has no significant effect on the prognosis of patients with AIS. Therefore, the current views on the role of CMBs in the prognoses of patients with IS are controversial. The use of anticoagulants and other drugs has also become a dilemma due to the special influence of CMBs on the prognosis of these patients. Due to the large number of patients with AF and CMBs, many studies have been conducted on the effects of CMBs on these patients and subsequent pharmacological treatments. However, at present, there are no relevant guidelines to guide the secondary preventive treatment of patients with stroke, CMBs, and AF. In this paper, we summarized the role of CMBs in AIS combined with AF and relevant preventive measures against the recurrence of stroke and the occurrence of intracerebral hemorrhage to help clarify the specifics of drug therapies for this group of patients.