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Soil salinity results in oxidative stress and heavy losses to crop production. The S-acylated protein SALT TOLERANCE RECEPTOR-LIKE CYTOPLASMIC KINASE 1 (STRK1) phosphorylates and activates CATALASE C (CatC) to improve rice (Oryza sativa L.) salt tolerance, but the molecular mechanism underlying its S-acylation involved in salt signal transduction awaits elucidation. Here, we show that the DHHC-type zinc finger protein DHHC09 S-acylates STRK1 at Cys5, Cys10, and Cys14 and promotes salt and oxidative stress tolerance by enhancing rice H2O2-scavenging capacity. This modification determines STRK1 targeting to the plasma membrane or lipid nanodomains and is required for its function. DHHC09 promotes salt signaling from STRK1 to CatC via transphosphorylation, and its deficiency impairs salt signal transduction. Our findings demonstrate that DHHC09 S-acylates and anchors STRK1 to the plasma membrane to promote salt signaling from STRK1 to CatC, thereby regulating H2O2 homeostasis and improving salt stress tolerance in rice. Moreover, overexpression of DHHC09 in rice mitigates grain yield loss under salt stress. Together, these results shed light on the mechanism underlying the role of S-acylation in RLK/RLCK-mediated salt signal transduction and provide a strategy for breeding highly salt-tolerant rice.
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Oryza , Tolerância ao Sal , Tolerância ao Sal/genética , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Homeostase , Dedos de Zinco , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Catalase (CAT) is often phosphorylated and activated by protein kinases to maintain hydrogen peroxide (H2O2) homeostasis and protect cells against stresses, but whether and how CAT is switched off by protein phosphatases remains inconclusive. Here, we identified a manganese (Mn2+)-dependent protein phosphatase, which we named PHOSPHATASE OF CATALASE 1 (PC1), from rice (Oryza sativa L.) that negatively regulates salt and oxidative stress tolerance. PC1 specifically dephosphorylates CatC at Ser-9 to inhibit its tetramerization and thus activity in the peroxisome. PC1 overexpressing lines exhibited hypersensitivity to salt and oxidative stresses with a lower phospho-serine level of CATs. Phosphatase activity and seminal root growth assays indicated that PC1 promotes growth and plays a vital role during the transition from salt stress to normal growth conditions. Our findings demonstrate that PC1 acts as a molecular switch to dephosphorylate and deactivate CatC and negatively regulate H2O2 homeostasis and salt tolerance in rice. Moreover, knockout of PC1 not only improved H2O2-scavenging capacity and salt tolerance but also limited rice grain yield loss under salt stress conditions. Together, these results shed light on the mechanisms that switch off CAT and provide a strategy for breeding highly salt-tolerant rice.
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Oryza , Catalase/genética , Catalase/metabolismo , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Proteína Fosfatase 1/metabolismo , Tolerância ao Sal/genética , Homeostase , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
The functions of the natural dsRNA sensors TLR3 (TRIF) and RIG-I (MAVS) are crucial during viral challenge and have not been accurately clarified in adaptive immune responses to rotavirus (RV) infection. In this study, we found that RV infection caused severe pathological damage to the small intestine of TLR3-/- and TRIF-/- mice. Our data found that dendritic cells from TLR3-/- and TRIF-/- mice had impaired Ag presentation to the RV and attenuated initiation of T cells upon viral infection. These attenuated functions resulted in impaired CD4+ T and CD8+ T function in mice lacking TLR3-TRIF signaling postinfection. Additionally, attenuated proliferative capacity of T cells from TLR3-/- and TRIF-/- mice was observed. Subsequently, we observed a significant reduction in the absolute number of memory T cells in the spleen and mesenteric lymph node (MLN) of TRIF-/- recipient mice following RV infection in a bone marrow chimeric model. Furthermore, there was reduced migration of type 2 classical dendritic cells from the intestine to MLNs after RV infection in TLR3-/- and TRIF-/- mice. Notably, RV infection resulted in attenuated killing of spleen and MLN tissues in TRIF-/- and MAVS-/- mice. Finally, we demonstrated that RV infection promoted apoptosis of CD8+ T cells in TRIF-/- and TLR3-/-MAVS-/- mice. Taken together, our findings highlight an important mechanism of TLR3 signaling through TRIF in mucosal T cell responses to RV and lay the foundation for the development of a novel vaccine.
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The motor cortex controls skilled arm movement by sending temporal patterns of activity to lower motor centres1. Local cortical dynamics are thought to shape these patterns throughout movement execution2-4. External inputs have been implicated in setting the initial state of the motor cortex5,6, but they may also have a pattern-generating role. Here we dissect the contribution of local dynamics and inputs to cortical pattern generation during a prehension task in mice. Perturbing cortex to an aberrant state prevented movement initiation, but after the perturbation was released, cortex either bypassed the normal initial state and immediately generated the pattern that controls reaching or failed to generate this pattern. The difference in these two outcomes was probably a result of external inputs. We directly investigated the role of inputs by inactivating the thalamus; this perturbed cortical activity and disrupted limb kinematics at any stage of the movement. Activation of thalamocortical axon terminals at different frequencies disrupted cortical activity and arm movement in a graded manner. Simultaneous recordings revealed that both thalamic activity and the current state of cortex predicted changes in cortical activity. Thus, the pattern generator for dexterous arm movement is distributed across multiple, strongly interacting brain regions.
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Córtex Motor/fisiologia , Movimento , Animais , Comportamento Animal , Feminino , Masculino , Camundongos , Tálamo/fisiologiaRESUMO
Endogenous retroviruses (ERVs) are the relics of ancient retroviruses occupying a substantial fraction of vertebrate genomes. However, knowledge about the functional association of ERVs with cellular activities remains limited. Recently, we have identified approximately 3,315 ERVs from zebrafish at genome-wide level, among which 421 ERVs were actively expressed in response to the infection of Spring viraemia of carp virus (SVCV). These findings demonstrated the previously unrecognized activity of ERVs in zebrafish immunity, thereby making zebrafish an attractive model organism for deciphering the interplay among ERVs, exogenous invading viruses, and host immunity. In the present study, we investigated the functional role of an envelope protein (Env38) derived from an ERV-E5.1.38-DanRer element in zebrafish adaptive immunity against SVCV in view of its strong responsiveness to SVCV infection. This Env38 is a glycosylated membrane protein mainly distributed on MHC-II+ antigen-presenting cells (APCs). By performing blockade and knockdown/knockout assays, we found that the deficiency of Env38 markedly impaired the activation of SVCV-induced CD4+ T cells and thereby led to the inhibition of IgM+/IgZ+ B cell proliferation, IgM/IgZ Ab production, and zebrafish defense against SVCV challenge. Mechanistically, Env38 activates CD4+ T cells by promoting the formation of pMHC-TCR-CD4 complex via cross-linking MHC-II and CD4 molecules between APCs and CD4+ T cells, wherein the surface subunit (SU) of Env38 associates with the second immunoglobin domain of CD4 (CD4-D2) and the first α1 domain of MHC-IIα (MHC-IIα1). Notably, the expression and functionality of Env38 was strongly induced by zebrafish IFNφ1, indicating that env38 acts as an IFN-stimulating gene (ISG) regulated by IFN signaling. To the best of our knowledge, this study is the first to identify the involvement of an Env protein in host immune defense against an exogenous invading virus by promoting the initial activation of adaptive humoral immunity. It improved the current understanding of the cooperation between ERVs and host adaptive immunity.
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Retrovirus Endógenos , Doenças dos Peixes , Infecções por Rhabdoviridae , Rhabdoviridae , Animais , Peixe-Zebra , Imunidade Humoral , Imunoglobulina M , Doenças dos Peixes/genéticaRESUMO
Programmed death-ligand 1/programmed cell death 1 (PD-L1/PD-1) is one of the most important immune checkpoints in humans and other mammalian species. However, the occurrence of the PD-L1/PD-1 checkpoint in evolutionarily ancient vertebrates remains elusive because of the absence of a PD-1 homolog before its appearance in tetrapods. In this article, we identified, to our knowledge, a novel PD-L1/B and T lymphocyte attenuator (BTLA) checkpoint in zebrafish by using an Edwardsiella tarda-induced bacterial infection model. Results showed that zebrafish (Danio rerio) PD-L1 (DrPD-L1) and BTLA (DrBTLA) were differentially upregulated on MHC class II+ macrophages (MÏs) and CD8+ T cells in response to E. tarda infection. DrPD-L1 has a strong ability to interact with DrBTLA, as shown by the high affinity (KD = 5.68 nM) between DrPD-L1/DrBTLA proteins. Functionally, the breakdown of DrPD-L1/DrBTLA interaction significantly increased the cytotoxicity of CD8+BTLA+ T cells to E. tarda-infected PD-L1+ MÏ cells and reduced the immune escape of E. tarda from the target MÏ cells, thereby enhancing the antibacterial immunity of zebrafish against E. tarda infection. Similarly, the engagement of DrPD-L1 by soluble DrBTLA protein diminished the tolerization of CD8+ T cells to E. tarda infection. By contrast, DrBTLA engagement by a soluble DrPD-L1 protein drives aberrant CD8+ T cell responses. These results were finally corroborated in a DrPD-L1-deficient (PD-L1-/-) zebrafish model. This study highlighted a primordial PD-L1/BTLA coinhibitory axis that regulates CD8+ T cell activation in teleost fish and may act as an alternative to the PD-L1/PD-1 axis in mammals. It also revealed a previously unrecognized strategy for E. tarda immune evasion by inducing CD8+ T cell tolerance to target MÏ cells through eliciting the PD-L1/BTLA checkpoint pathway.
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Antígeno B7-H1 , Peixe-Zebra , Humanos , Animais , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T CD8-Positivos , Mamíferos , Receptores Imunológicos/metabolismoRESUMO
The ß-relaxation is one of the major dynamic behaviors in metallic glasses (MGs) and exhibits diverse features. Despite decades of efforts, the understanding of its structural origin and contribution to the overall dynamics of MG systems is still unclear. Here two palladium-based PdâCuâP and PdâNiâP MGs are reported with distinct different ß-relaxation behaviors and reveal the structural origins for the difference using the advanced X-ray photon correlation spectroscopy and absorption fine structure techniques together with the first-principles calculations. The pronounced ß-relaxation and fast atomic dynamics in the PdâCuâP MG mainly come from the strong mobility of Cu atoms and their locally favored structures. In contrast, the motion of Ni atoms is constrained by P atoms in the PdâNiâP MG, leading to the weakened ß-relaxation peak and sluggish dynamics. The correlation of atomic dynamics with microscopic structures provides a way to understand the structural origins of different dynamic behaviors as well as the nature of aging in disordered materials.
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OBJECTIVE: Immunotherapy-tyrosine kinase inhibitor (IO-TKI) therapy has revolutionized the treatment landscape for metastatic clear cell renal cell carcinoma (mccRCC); however, the absence of effective biomarkers poses a challenge in predicting the efficacy of these regimens. This study aims to explore the predictive and prognostic value of serum immunoglobulin A (IgA) in mccRCC patients undergoing IO-TKI therapy. METHODS: Ninety-six mccRCC patients treated with IO-TKI therapy from 2019 to 2023 were enrolled and serum IgA levels were assessed at the pretreatment baseline and after 3 months of treatment. RESULTS: Notably, baseline levels of IgA showed no correlation with the objective response rate. However, patients achieving complete or partial responses exhibited a remarkable decrease in IgA levels, while those with stable or progressive disease displayed an increase in IgA levels after 3 months of treatment. Furthermore, the dynamic alteration in IgA levels after 3 months of treatment demonstrated predictive value for both progression-free survival (PFS) and overall survival (OS). The time-dependent receiver operating characteristic curves exhibited outstanding performance in predicting PFS (AUC 0.793) and OS (AUC 0.738). CONCLUSION: Taken together, this study demonstrates that dynamic alteration of serum IgA after 3 months of treatment was significantly correlated with prognosis and therapeutic efficacy in mccRCC patients.
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Biomarcadores Tumorais , Carcinoma de Células Renais , Imunoglobulina A , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/secundário , Carcinoma de Células Renais/patologia , Masculino , Feminino , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Neoplasias Renais/sangue , Pessoa de Meia-Idade , Imunoglobulina A/sangue , Taxa de Sobrevida , Prognóstico , Idoso , Biomarcadores Tumorais/sangue , Seguimentos , Adulto , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Imunoterapia/métodos , Idoso de 80 Anos ou maisRESUMO
BACKGROUND: In recent years, with benefits from the continuous improvement of clinical technology and the advantage of fertility preservation, the application of embryo cryopreservation has been growing rapidly worldwide. However, amidst this growth, concerns about its safety persist. Numerous studies have highlighted the elevated risk of perinatal complications linked to frozen embryo transfer (FET), such as large for gestational age (LGA) and hypertensive disorders during pregnancy. Thus, it is imperative to explore the potential risk of embryo cryopreservation and its related mechanisms. METHODS: Given the strict ethical constraints on clinical samples, we employed mouse models in this study. Three experimental groups were established: the naturally conceived (NC) group, the fresh embryo transfer (Fresh-ET) group, and the FET group. Blastocyst formation rates and implantation rates were calculated post-embryo cryopreservation. The impact of FET on fetal growth was evaluated upon fetal and placental weight. Placental RNA-seq was conducted, encompassing comprehensive analyses of various comparisons (Fresh-ET vs. NC, FET vs. NC, and FET vs. Fresh-ET). RESULTS: Reduced rates of blastocyst formation and implantation were observed post-embryo cryopreservation. Fresh-ET resulted in a significant decrease in fetal weight compared to NC group, whereas FET reversed this decline. RNA-seq analysis indicated that the majority of the expression changes in FET were inherited from Fresh-ET, and alterations solely attributed to embryo cryopreservation were moderate. Unexpectedly, certain genes that showed alterations in Fresh-ET tended to be restored in FET. Further analysis suggested that this regression may underlie the improvement of fetal growth restriction in FET. The expression of imprinted genes was disrupted in both FET and Fresh-ET groups. CONCLUSION: Based on our experimental data on mouse models, the impact of embryo cryopreservation is less pronounced than other in vitro manipulations in Fresh-ET. However, the impairment of the embryonic developmental potential and the gene alterations in placenta still suggested it to be a risky operation.
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Criopreservação , Transferência Embrionária , Placenta , Criopreservação/métodos , Feminino , Gravidez , Animais , Camundongos , Transferência Embrionária/métodos , Placenta/metabolismo , Embrião de Mamíferos , Implantação do Embrião/genética , Desenvolvimento Fetal/genética , Blastocisto/metabolismoRESUMO
Teleost fish are indispensable model organisms for comparative immunology research that should lead to an improved understanding of the general principles of vertebrate immune system design. Although numerous studies on fish immunology have been conducted, knowledge about the cell types that orchestrate piscine immune systems remains limited. Here, we generated a comprehensive atlas of immune cell types in zebrafish spleen on the basis of single-cell transcriptome profiling. We identified 11 major categories from splenic leukocyte preparations, including neutrophils, natural killer cells, macrophages/myeloid cells, T cells, B cells, hematopoietic stem and progenitor cells, mast cells, remnants of endothelial cells, erythroid cells, erythroid progenitors, and a new type of serpin-secreting cells. Notably, we derived 54 potential subsets from these 11 categories. These subsets showed differential responses to spring viremia of carp virus (SVCV) infection, implying that they have diverse roles in antiviral immunity. Additionally, we landscaped the populations with the induced expression of interferons and other virus-responsive genes. We found that trained immunity can be effectively induced in the neutrophil and M1-macrophage subsets by vaccinating zebrafish with inactivated SVCV. Our findings illustrated the complexity and heterogeneity of the fish immune system, which will help establish a new paradigm for the improved understanding of fish immunology.
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Infecções por Rhabdoviridae , Peixe-Zebra , Animais , Peixe-Zebra/genética , Baço , Células Endoteliais , Perfilação da Expressão GênicaRESUMO
RESEARCH QUESTION: Does frozen embryo transfer (FET) increase the risk of allergic diseases in offspring? DESIGN: This study followed up 653 singleton children: 166 born through FET and 487 born through natural conception. Demographic characteristics, perinatal information and allergic diseases of children and their parents were collected through clinical medical systems and questionnaires. Among these 653 children, allergen-specific immunoglobulin E (IgE) testing was performed using peripheral blood samples collected from 207 children: 145 in the FET group and 62 in the natural conception group. The prevalence of allergic diseases and positive rates of allergen-specific IgE testing were compared between the two groups with adjustments for confounding factors. RESULTS: The prevalence of food allergy was significantly higher in children born through FET compared with children born through natural conception (adjusted ORâ¯=â¯3.154, 95% CI 1.895-5.250; P < 0.001). In addition, positive rates of food allergen sensitization were higher in children in the FET group compared with children in the natural conception group (adjusted ORâ¯=â¯5.769, 95% CI 2.859-11.751, P < 0.001). Children in the FET group had a higher positive sensitization rate to at least one allergen compared with children in the natural conception group (adjusted ORâ¯=â¯3.127, 95% CI 1.640-5.961, P < 0.001). No association was observed between FET and other allergic diseases, including asthma (Pâ¯=â¯0.136), atopic dermatitis (Pâ¯=â¯0.130) and allergic rhinitis (Pâ¯=â¯0.922). Allergen sensitization IgE testing indicated no differences between the two groups in terms of positive sensitization rates of other common allergens, including animal and insect allergens (Pâ¯=â¯0.627), inhaled outdoor allergens (Pâ¯=â¯0.915) and inhaled outdoor allergens (Pâ¯=â¯0.544). CONCLUSION: This study suggests that children born through FET have increased risk of developing food allergy in early childhood.
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Discus fish (Symphysodon aequifasciatus) exhibit a unique parental care behavior: adult discus produces secretion through their skin, on which the larvae live after birth. The immune components in the skin mucus of parental discus would change during different parental care. C-type lectins (CTLs) could identify and eliminate pathogenic microorganisms and play important roles in innate immunity. Studies on CTLs of discus fish especially during parental care, however, are scarce. Here, we identified 186 CTL genes that distributed in 27 linkage groups based on discus genome. Phylogenetic analysis showed that S. aequifasciatus CTL (SaCTL) members were grouped into 14 subfamilies. A total of 80 gene replication events occurred, of which 15 pairs were subjected to segmental duplication and 65 pairs underwent tandem duplication. Ka/Ks ranged from 0.11 (SaCTL25/SaCTL158) to 0.68 (SaCTL36/SaCTL69), all undergoing purifying selection. RNA-seq analysis revealed that SaCTL members, including duplicated genes, in the skin of parental discus show distinct expression patterns in different care stages and between male and female parents. The SaCTL11 was differentially expressed in most care stages and reached the maximum after eggs spawned, but the expression of its paired SaCTL14 was low in each stage. The SaCTL39 increased first and then decreased, reaching a peak in eggs spawned, while paired SaCTL48 first decreased and then increased, reaching a peak in hatched eggs. The SaCTL50 was differentially expressed only in female fish during care, but not in male fish. These results provide new insights into the evolution and potential functional differentiation of CTLs in discus fish during parental care.
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Ciclídeos , Lectinas Tipo C , Feminino , Masculino , Animais , Filogenia , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Ciclídeos/genética , Pele/metabolismo , LarvaRESUMO
The establishment of an appropriate costimulatory phenotype is crucial for dendritic cells (DCs) to maintain a homeostatic state with optimal immune surveillance and immunogenic activities. The upregulation of CD80/86 and CD40 is a hallmark costimulatory phenotypic switch of DCs from a steady state to an activated one for T cell activation. However, knowledge of the regulatory mechanisms underlying this process remains limited. In this study, we identified a Zbtb46 homolog from a zebrafish model. Zbtb46 deficiency resulted in upregulated cd80/86 and cd40 expression in kidney marrow-derived DCs (KMDCs) of zebrafish, which was accompanied with a remarkable expansion of CD4+/CD8+ T cells and accumulation of KMDCs in spleen of naive fish. Zbtb46 -/- splenic KMDCs exhibited strong stimulatory activity for CD4+ T cell activation. Chromatin immunoprecipitation-quantitative PCR and mass spectrometry assays showed that Zbtb46 was associated with promoters of cd80/86 and cd40 genes by binding to a 5'-TGACGT-3' motif in resting KMDCs, wherein it helped establish a repressive histone epigenetic modification pattern (H3K4me0/H3K9me3/H3K27me3) by organizing Mdb3/organizing nucleosome remodeling and deacetylase and Hdac3/nuclear receptor corepressor 1 corepressor complexes through the recruitment of Hdac1/2 and Hdac3. On stimulation with infection signs, Zbtb46 disassociated from the promoters via E3 ubiquitin ligase Cullin1/Fbxw11-mediated degradation, and this reaction can be triggered by the TLR9 signaling pathway. Thereafter, cd80/86 and cd40 promoters underwent epigenetic reprogramming from the repressed histone modification pattern to an activated pattern (H3K4me3/H3K9ac/H3K27ac), leading to cd80/86 and cd40 expression and DC activation. These findings revealed the essential role of Zbtb46 in maintaining DC homeostasis by suppressing cd80/86 and cd40 expression through epigenetic mechanisms.
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Linfócitos T CD8-Positivos , Peixe-Zebra , Animais , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Antígenos CD40 , Moléculas de Adesão Celular/metabolismo , Células Dendríticas , Epigênese Genética , Ativação LinfocitáriaRESUMO
Background: Radiotherapy is an effective treatment for indolent non-Hodgkin lymphoma (iNHL); however, the optimal radiotherapy dose remains to be determined. We hypothesize that a suitable dose may exist between 4 and 24 Gy. Methods: This prospective multicenter phase II trial intends to recruit 73 sites of iNHL patients, who will receive involved-site radiotherapy of 12 Gy in four fractions. The primary objective is the 6-month clinical complete response rate. Tumor tissue, blood and conjunctival specimens will be collected to identify potential predictive biomarkers. Discussion: The CLCG-iNHL-01 trial will evaluate the efficacy and toxicity of 12 Gy in patients with iNHL and provide information on a novel hypofractionation regimen of low-dose radiotherapy. Clinical Trial Registration: NCT05543070 (ClinicalTrials.gov).
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Linfoma não Hodgkin , Humanos , Estudos Prospectivos , Linfoma não Hodgkin/tratamento farmacológico , Resultado do Tratamento , Ensaios Clínicos Fase II como Assunto , Estudos Multicêntricos como AssuntoRESUMO
INTRODUCTION: With the aging of the population in China, the prevalence of atopic dermatitis (AD) is high in elderly patients. These patients usually have more comorbidities and they need more effective and safer treatments. Dupilumab is an anti-interleukin-4 (IL-4) receptor monoclonal antibody which was approved for the treatment of moderate-to-severe AD. METHODS: Elderly patients (60 years or older) with moderate-to-severe AD who treated with dupilumab were included. Eczema Area and Severity Index (EASI) score, Peak Pruritus Numerical Rating Scale (PP-NRS), EASI-50, EASI-75, and EASI-50 were evaluated. The efficacy in subgroups was also investigated. RESULTS: Fifty-eight patients were enrolled. The EASI score and PP-NRS score were significantly reduced at weeks 4, 16, 28, and 52. 91.2% and 79.4% of the patients achieved EASI-50 and EASI-75 at week 16, respectively. 95.8% and 87.5% patients achieved EASI-50 and EASI-75 at week 52, respectively. Adverse events were reported in 10 (17.2%) patients, and no severe adverse event was reported. Male, older age, and moderate AD (EASI <21) were related to better efficacy. CONCLUSIONS: This study demonstrated that dupilumab is effective and safe in elderly patients with AD.
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Anticorpos Monoclonais Humanizados , Dermatite Atópica , Índice de Gravidade de Doença , Humanos , Dermatite Atópica/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , China , Resultado do Tratamento , Idoso de 80 Anos ou mais , Prurido/tratamento farmacológico , População do Leste AsiáticoRESUMO
Metabolic engineering frequently makes use of point mutation and saturation mutation library creation. At present, sequencing is the only reliable and direct technique to detect point mutation and screen saturation mutation library. In this study, mismatch amplification mutation assay (MAMA) PCR was used to detect point mutation and screen saturation mutation library. In order to fine-tune the expression of odhA encoding 2-oxoglutarate dehydrogenase E1 component, a saturating mutant library of the RBS of odhA was created in Corynebacterium glutamicum P12 based on the CRISPR-Cas2a genome editing system, which increased the L-proline production by 81.3%. MAMA PCR was used to filter out 42% of the non-mutant transformants in the mutant library, which effectively reduced the workload of the subsequent fermentation test and the number of sequenced samples. The rapid and sensitive MAMA-PCR method established in this study provides a general strategy for detecting point mutations and improving the efficiency of mutation library screening. KEY POINTS: ⢠MAMA PCR was optimized and developed to detect point mutation. ⢠MAMA PCR greatly improves the screening efficiency of point mutation. ⢠Attenuation of odhA expression in P12 effectively improves proline production.
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Corynebacterium glutamicum , Mutação Puntual , Mutação , Sequência de Bases , Corynebacterium glutamicum/genética , Reação em Cadeia da Polimerase/métodosRESUMO
BACKGROUND: Serial excision remains the most commonly used surgical procedure for treating congenital melanocytic nevus (CMN). It is critical to remove as much of the lesion as possible with each procedure to reduce the number of procedures and to shorten the treatment duration. OBJECTIVE: To investigate the clinical efficacy of W-plasty serial excision for the repair of postoperative CMN defects. METHODS: A retrospective analysis of patients with medium CMN was conducted from April 2018 to March 2022. Treatment options were divided into elliptical serial excision (10 cases) and W-plasty serial excision (10 cases). RESULTS: Follow-up occurred over 6 months. The number of elliptical excision procedures was 2 to 4 (mean 2.9). The scar-to-lesion length ratio was 1.5 to 2.0 (mean 1.7). The mean Vancouver Scar Scale (VSS) score was 5.40 ± 0.42. The number of W-plasty excision procedures was 2 to 3 (mean 2.2). The scar-to-lesion length ratio was 1.2 to 1.5 (mean 1.4). The mean VSS score was 2.70 ± 0.26. W-plasty excision was superior to elliptical excision regarding the number of procedures and the effect on postoperative scars. CONCLUSION: W-plasty serial excision can be considered a suitable option for the excision of medium CMN, leading to excellent results.
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The heart pumps blood against the mechanical afterload from arterial resistance, and increased afterload may alter cardiac electrophysiology and contribute to life-threatening arrhythmias. However, the cellular and molecular mechanisms underlying mechanoelectric coupling in cardiomyocytes remain unclear. We developed an innovative patch-clamp-in-gel technology to embed cardiomyocytes in a three-dimensional (3D) viscoelastic hydrogel that imposes an afterload during regular myocyte contraction. Here, we investigated how afterload affects action potentials, ionic currents, intracellular Ca2+ transients, and cell contraction of adult rabbit ventricular cardiomyocytes. We found that afterload prolonged action potential duration (APD), increased transient outward K+ current, decreased inward rectifier K+ current, and increased L-type Ca2+ current. Increased Ca2+ entry caused enhanced Ca2+ transients and contractility. Moreover, elevated afterload led to discordant alternans in APD and Ca2+ transient. Ca2+ alternans persisted under action potential clamp, indicating that the alternans was Ca2+ dependent. Furthermore, all these afterload effects were significantly attenuated by inhibiting nitric oxide synthase 1 (NOS1). Taken together, our data reveal a mechano-chemo-electrotransduction (MCET) mechanism that acutely transduces afterload through NOS1-nitric oxide signaling to modulate the action potential, Ca2+ transient, and contractility. The MCET pathway provides a feedback loop in excitation-Ca2+ signaling-contraction coupling, enabling autoregulation of contractility in cardiomyocytes in response to afterload. This MCET mechanism is integral to the individual cardiomyocyte (and thus the heart) to intrinsically enhance its contractility in response to the load against which it has to do work. While this MCET is largely compensatory for physiological load changes, it may also increase susceptibility to arrhythmias under excessive pathological loading.
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Arritmias Cardíacas/fisiopatologia , Fenômenos Eletrofisiológicos , Hidrogéis , Miócitos Cardíacos/fisiologia , Potenciais de Ação/fisiologia , Animais , Fenômenos Biomecânicos , Cálcio , Sinalização do Cálcio/fisiologia , Células Cultivadas , Masculino , Contração Miocárdica/fisiologia , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Técnicas de Patch-Clamp , Coelhos , Transdução de Sinais , Substâncias ViscoelásticasRESUMO
Spinal cord injury (SCI) is a serious central nervous system disease with high disability and mortality rates and complex pathophysiologic mechanisms. MicroRNA (miRNA), as a kind of non-coding RNA, plays an important role in SCI. miRNA is involved in the regulation of inflammatory response, oxidative stress, axonal regeneration, and apoptosis after SCI, and interacts with long non-coding RNA (lncRNA) and circular RNA (circRNA) to regulate the pathophysiological process of SCI. This paper summarizes the changes in miRNA expression after SCI, and reviews the targeting mechanism of miRNA in SCI and the current research status of miRNA-targeted drugs to provide new targets and new horizons for basic and clinical research on SCI.
Assuntos
MicroRNAs , Traumatismos da Medula Espinal , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/fisiopatologia , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/fisiologia , Humanos , Animais , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Longo não Codificante/fisiologia , RNA Circular/genética , RNA Circular/fisiologia , RNA Circular/metabolismo , Estresse Oxidativo , Apoptose/genéticaRESUMO
Spring viremia of carp virus (SVCV) is a severe infectious pathogen that causes high rates of mortality in cyprinids and other fish species. Despite numerous investigations of SVCV infection, the underlying molecular mechanisms remain poorly understood. In this study, we found that the SVCV matrix protein (SVCV-M) played an inhibitory role in the host interferon (IFN) response by targeting the MAVS/TRAF3 signaling axis, thereby uncovering a previously unrecognized mechanism of SVCV escape from host innate antiviral immunity. Mechanistically, SVCV-M was located at the mitochondria independent of MAVS, which allowed SVCV-M to build an arena for competition with the MAVS platform. A microscale thermophoresis assay showed that SVCV-M had a high affinity for TRAF3, as indicated by a lower equilibrium dissociation constant (KD) value than that of MAVS with TRAF3. Therefore, the association of MAVS with TRAF3 was competitively impaired by SVCV-M in a dose-dependent manner. Accordingly, SVCV-M showed a potent ability to inhibit the K63-linked polyubiquitination of TRAF3. This inhibition was accompanied by the impairment of the IFN response, as shown by the marked decline in IFN-φ1-promoter (pro) luciferase reporter activity. By constructing truncated TRAF3 and SVCV-M proteins, the RING finger, zinc finger, and coiled-coil domains of TRAF3 and the hydrophobic-pocket-like structure formed by the α2-, α3-, and α4-helices of SVCV-M may be the major target and antagonistic modules responsible for the protein-protein interaction between the TRAF3 and SVCV-M proteins. These findings highlighted the intervention of SVCV-M in host innate immunity, thereby providing new insights into the extensive participation of viral matrix proteins in multiple biological activities. IMPORTANCE The matrix protein of SVCV (SVCV-M) is an indispensable structural element for nucleocapsid condensation and virion formation during viral morphogenesis, and it connects the core nucleocapsid particle to the outer membrane within the mature virus. Previous studies have emphasized the architectural role of SVCV-M in viral construction; however, the potential nonstructural functions of SVCV-M in viral replication and virus-host interactions remain poorly understood. In this study, we identified the inhibitory role of the SVCV-M protein in host IFN production by competitively recruiting TRAF3 from the MAVS signaling complex and impairing TRAF3 activation via inhibition of K63-linked polyubiquitination. This finding provided new insights into the regulatory role of SVCV-M in host innate immunity, which highlighted the broader functionality of rhabdovirus matrix protein apart from being a structural protein. This study also revealed a previously unrecognized mechanism underlying SVCV immune evasion by inhibiting the IFN response by targeting the MAVS/TRAF3 signaling axis.