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Csm, a type III-A CRISPR-Cas interference complex, is a CRISPR RNA (crRNA)-guided RNase that also possesses target RNA-dependent DNase and cyclic oligoadenylate (cOA) synthetase activities. However, the structural features allowing target RNA-binding-dependent activation of DNA cleavage and cOA generation remain unknown. Here, we report the structure of Csm in complex with crRNA together with structures of cognate or non-cognate target RNA bound Csm complexes. We show that depending on complementarity with the 5' tag of crRNA, the 3' anti-tag region of target RNA binds at two distinct sites of the Csm complex. Importantly, the interaction between the non-complementary anti-tag region of cognate target RNA and Csm1 induces a conformational change at the Csm1 subunit that allosterically activates DNA cleavage and cOA generation. Together, our structural studies provide crucial insights into the mechanistic processes required for crRNA-meditated sequence-specific RNA cleavage, RNA target-dependent non-specific DNA cleavage, and cOA generation.
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Proteínas Associadas a CRISPR/ultraestrutura , Sistemas CRISPR-Cas/fisiologia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/fisiologia , Proteínas de Bactérias , Proteínas Associadas a CRISPR/química , DNA/química , Desoxirribonucleases/metabolismo , Endorribonucleases/metabolismo , Modelos Moleculares , RNA/química , RNA Bacteriano/química , RNA Guia de Cinetoplastídeos/química , Ribonucleases/metabolismoRESUMO
Although the use of Doxorubicin (Dox) is extensive in the treatment of malignant tumor, the toxic effects of Dox on the heart can cause myocardial injury. Therefore, it is necessary to find an alternative drug to alleviate the Dox-induced cardiotoxicity. Dihydroartemisinin (DHA) is a semisynthetic derivative of artemisinin, which is an active ingredient of Artemisia annua. The study investigates the effects of DHA on doxorubicin-induced cardiotoxicity and ferroptosis, which are related to the activation of Nrf2 and the regulation of autophagy. Different concentrations of DHA were administered by gavage for 4 weeks in mice. H9c2 cells were pretreated with different concentrations of DHA for 24 h in vitro. The mechanism of DHA treatment was explored through echocardiography, biochemical analysis, real-time quantitative PCR, western blotting analysis, ROS/DHE staining, immunohistochemistry, and immunofluorescence. In vivo, DHA markedly relieved Dox-induced cardiac dysfunction, attenuated oxidative stress, alleviated cardiomyocyte ferroptosis, activated Nrf2, promoted autophagy, and improved the function of lysosomes. In vitro, DHA attenuated oxidative stress and cardiomyocyte ferroptosis, activated Nrf2, promoted clearance of autophagosomes, and reduced lysosomal destruction. The changes of ferroptosis and Nrf2 depend on selective degradation of keap1 and recovery of lysosome. We found for the first time that DHA could protect the heart from the toxic effects of Dox-induced cardiotoxicity. In addition, DHA significantly alleviates Dox-induced ferroptosis through the clearance of autophagosomes, including the selective degradation of keap1 and the recovery of lysosomes.
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Artemisininas , Autofagia , Cardiotoxicidade , Doxorrubicina , Ferroptose , Miócitos Cardíacos , Fator 2 Relacionado a NF-E2 , Artemisininas/farmacologia , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Autofagia/efeitos dos fármacos , Doxorrubicina/efeitos adversos , Doxorrubicina/toxicidade , Camundongos , Ferroptose/efeitos dos fármacos , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Cardiotoxicidade/metabolismo , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Linhagem Celular , RatosRESUMO
Antimony selenide (Sb2 Se3 ) is a highly promising photovoltaic material thanks to its outstanding optoelectronic properties, as well as its cost-effective and eco-friendly merits. However, toxic CdS is widely used as an electron transport layer (ETL) in efficient Sb2 Se3 solar cells, which largely limit their development toward market commercialization. Herein, an effective green Cd-free ETL of SnOx is introduced and deposited by atomic layer deposition method. Additionally, an important post-annealing treatment is designed to further optimize the functional layers and the heterojunction interface properties. Such engineering strategy can optimize SnOx ETL with higher nano-crystallinity, higher carrier density, and less defect groups, modify Sb2 Se3 /SnOx heterojunction with better interface performance and much desirable "spike-like" band alignment, and also improve the Sb2 Se3 light absorber layer quality with passivated bulk defects and prolonged carrier lifetime, and therefore to enhance carrier separation and transport while suppressing non-radiative recombination. Finally, the as-fabricated Cd-free Mo/Sb2 Se3 /SnOx /ITO/Ag thin-film solar cell exhibits a stimulating efficiency of 7.39%, contributing a record value for Cd-free substrate structured Sb2 Se3 solar cells reported to date. This work provides a viable strategy for developing and broadening practical applications of environmental-friendly Sb2 Se3 photovoltaic devices.
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Halocins are antimicrobial peptides secreted by haloarchaea capable of inhibiting the growth of other haloarchaea or bacteria. Halocin H4 (HalH4) is secreted by the model halophilic archaeon Haloferax mediterranei ATCC 33500. Despite attempts to express halH4 heterologously in Escherichia coli and subsequent careful renaturation procedures commonly employed for haloarchaeal proteins, no active halocin was obtained. However, it was discovered that the antihaloarchaeal activity of this halocin could be activated through cleavage by halolysin R4 (HlyR4), a serine protease also secreted by Hfx. mediterranei ATCC 33500. Replacement of the cysteine at the number 115 amino acid with glycine and deletion of the internal trans-membrane region (15 aa) markedly abolished HalH4's antihaloarchaeal activity. Compared to the N-terminus, the C-terminal amino acid sequence was found to be more crucial for HalH4 to exert its antihaloarchaeal activity. Mass spectrometry analysis revealed that the biologically active antihaloarchaeal peptide produced after hydrolytic cleavage by HlyR4 was the C-terminus of HalH4, suggesting a potential mechanism of action involving pore formation within competitor species' cell membranes. Taken together, this study offers novel insights into the interplay between halocins and secreted proteases, as well as their contribution to antagonistic interaction within haloarchaea. IMPORTANCE: The antihaloarchaeal function of halocin H4 (HalH4) can be activated by extracellular proteases from haloarchaea, as demonstrated in this study. Notably, we report the first instance of halocin activation through proteolytic cleavage, highlighting its significance in the field. The C-terminus of HalH4 (CTH4) has been identified as the antihaloarchaeal peptide present in hydrolysates generated by HlyR4. The CTH4 exhibited inhibitory activity against a range of haloarchaeal species (Haloarchaeobius spp., Haloarcula spp., Haloferax spp., Halorubellus spp., and Halorubrum spp.), as well as selected bacterial species (Aliifodinibius spp. and Salicola spp.), indicating its broad-spectrum inhibitory potential across domains. The encoding gene of halocin HalH4, halH4, from the model halophilic archaeon Haloferax mediterranei ATCC 33500 can be expressed in Escherichia coli without codon optimization.
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Haloferax mediterranei , Haloferax , Serina Endopeptidases/metabolismo , Peptídeos/metabolismo , Haloferax/metabolismo , Escherichia coli/genéticaRESUMO
Klebsiella pneumoniae (K. pneumoniae) is a gram-negative conditionally pathogenic bacterium that causes disease primarily in immunocompromised individuals. Recently, highly virulent K. pneumoniae strains have caused severe disease in healthy individuals, posing significant challenges to global infection control. Capsular polysaccharide (CPS), a major virulence determinant of K. pneumoniae, protects the bacteria from being killed by the host immune system, suggesting an urgent need for the development of drugs to prevent or treat K. pneumoniae infections. In this study, BY3 compounded traditional Chinese medicine residue (TCMR) was carried out using Lactobacillus rhamnosus as a fermentation strain, and BY3 compounded TCMR fermentation broth (BY3 fermentation broth) was obtained. The transcription of K. pneumoniae CPS-related biosynthesis genes after treatment with BY3 fermentation broth was detected using quantitative real-time polymerase chain reaction. The effects of BY3 fermentation broth on K. pneumoniae serum killing, macrophage phagocytosis, complement deposition and human ß-defensin transcription were investigated. The therapeutic effect of BY3 fermentation broth on K. pneumoniae-infected mice was also observed, and the major active components of BY3 fermentation broth were analysed via LCâMS analysis, network pharmacology, and molecular docking. The results showed that BY3 fermentation broth inhibited K. pneumoniae CPS production and downregulated transcription of CPS-related biosynthesis genes, which weakened bacterial resistance to serum killing and phagocytosis, while promoting bacterial surface complement C3 deposition and human ß-defensin expression. BY3 fermentation broth demonstrated safety and therapeutic effects in vivo and in vitro, restoring body weight and visceral indices, significantly reducing the organ bacterial load and serum cytokine levels, and alleviating pathological organ damage in mice. In addition, three natural compounds-oleanolic acid, quercetin, and palmitoleic acid-were identified as the major active components in the BY3 fermentation broth. Therefore, BY3 fermentation broth may be a promising strategy for the prevention or treatment of K. pneumoniae infections.
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BACKGROUND: Leucine, a branched-chain amino acid, participates in the regulation of lipid metabolism and the composition of the intestinal microbiota. However, the related mechanism remains unclear. OBJECTIVES: Here, we aimed to reveal the potential mechanisms by which hepatic CYP7A1 (a rate-limiting enzyme for bile acid [BA] synthesis) and gut microbiota coregulate BA synthesis under leucine deprivation. METHODS: To this end, 8-wk-old C57BL/6J mice were fed with either regular diets or leucine-free diets for 1 wk. Then, we investigated whether secondary BAs were synthesized by Turicibacter sanguinis in 7-wk-old C57BL/6J germ-free mice gavaged with T. sanguinis for 2 wk by determining BA concentrations in the plasma, liver, and cecum contents using liquid chromatography-tandem mass spectrometry. RESULTS: The results showed that leucine deprivation resulted in a significant increase in total BA concentration in the plasma and an increase in the liver, but no difference in total BA was observed in the cecum contents before and after leucine deprivation. Furthermore, leucine deprivation significantly altered BA profiles such as taurocholic acid and ω-muricholic acid in the plasma, liver, and cecum contents. CYP7A1 expression was significantly upregulated in the liver under leucine deprivation. Leucine deprivation also regulated the composition of the gut microbiota; specifically, it significantly upregulated the relative abundance of T. sanguinis, thus enhancing the conversion of primary BAs into secondary BAs by intestinal T. sanguinis in mice. CONCLUSIONS: Overall, leucine deprivation regulated BA profiles in enterohepatic circulation by upregulating hepatic CYP7A1 expression and increasing intestinal T. sanguinis abundance. Our findings reveal the contribution of gut microbiota to BA metabolism under dietary leucine deprivation.
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Ácidos e Sais Biliares , Colesterol 7-alfa-Hidroxilase , Microbioma Gastrointestinal , Leucina , Fígado , Camundongos Endogâmicos C57BL , Regulação para Cima , Animais , Colesterol 7-alfa-Hidroxilase/metabolismo , Colesterol 7-alfa-Hidroxilase/genética , Ácidos e Sais Biliares/metabolismo , Leucina/metabolismo , Fígado/metabolismo , Camundongos , Masculino , Actinobacteria/metabolismo , MultiômicaRESUMO
OBJECTIVES: To evaluate the prognostic value of radiomics features based on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) images in patients with cardiac amyloidosis (CA). METHODS: This retrospective study included 120 CA patients undergoing CMR at three institutions. Radiomics features were extracted from global and three different segments (base, mid-ventricular, and apex) of left ventricular (LV) on short-axis LGE images. Primary endpoint was all-cause mortality. The predictive performance of the radiomics features and semi-quantitative and quantitative LGE parameters were compared by ROC. The AUC was used to observe whether Rad-score had an incremental value for clinical stage. The Kaplan-Meier curve was used to further stratify the risk of CA patients. RESULTS: During a median follow-up of 12.9 months, 30% (40/120) patients died. There was no significant difference in the predictive performance of the radiomics model in different LV sections in the validation set (AUCs of the global, basal, middle, and apical radiomics model were 0.75, 0.77, 0.76, and 0.77, respectively; all p > 0.05). The predictive performance of the Rad-score of the base-LV was better than that of the LGE total enhancement mass (AUC:0.77 vs. 0.54, p < 0.001) and LGE extent (AUC: 0.77 vs. 0.53, p = 0.004). Rad-score combined with Mayo stage had better predictive performance than Mayo stage alone (AUC: 0.86 vs. 0.81, p = 0.03). Rad-score (≥ 0.66) contributed to the risk stratification of all-cause mortality in CA. CONCLUSIONS: Compared to quantitative LGE parameters, radiomics can better predict all-cause mortality in CA, while the combination of radiomics and Mayo stage could provide higher predictive accuracy. CLINICAL RELEVANCE STATEMENT: Radiomics analysis provides incremental value and improved risk stratification for all-cause mortality in patients with cardiac amyloidosis. KEY POINTS: ⢠Radiomics in LV-base was superior to LGE semi-quantitative and quantitative parameters for predicting all-cause mortality in CA. ⢠Rad-score combined with Mayo stage had better predictive performance than Mayo stage alone or radiomics alone. ⢠Rad-score ≥ 0.66 was associated with a significantly increased risk of all-cause mortality in CA patients.
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Amiloidose , Gadolínio , Humanos , Gadolínio/farmacologia , Meios de Contraste/farmacologia , Estudos Retrospectivos , Radiômica , Amiloidose/diagnóstico por imagem , Prognóstico , Valor Preditivo dos Testes , Imagem Cinética por Ressonância Magnética/métodos , Função Ventricular EsquerdaRESUMO
A novel cyclooxygenase-2 (COX-2) targeted H2S-activated cancer-specific fluorescent probe, namely, COX2-H2S, was designed and synthesized, with naphthalimide as the fluorophore and indomethacin as the targeting group. This H2S-sensing probe was developed to differentiate tumor cells from normal cells and was tested in living cells, Caenorhabditis elegans (C. elegans), and zebrafish. The probe could successfully be used for imaging endogenous and exogenous H2S in living cells, demonstrating high sensitivity and specificity and strong anti-interference. COX2-H2S had the ability to not only discern cancer cells from normal cells but also specifically recognize 9L/lacZ cells from other glioblastoma cells (U87-MG and LN229). It could also be successfully applied for the fluorescent live imaging of H2S in both C. elegans and zebrafish.
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Sulfeto de Hidrogênio , Neoplasias , Animais , Humanos , Caenorhabditis elegans , Ciclo-Oxigenase 2 , Corantes Fluorescentes , Sulfeto de Hidrogênio/análise , Neoplasias/diagnóstico por imagem , Imagem Óptica/métodos , Peixe-Zebra , Linhagem Celular TumoralRESUMO
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a type of polyhydroxyalkanoates (PHA) that exhibits numerous outstanding properties and is naturally synthesized and elaborately regulated in various microorganisms. However, the regulatory mechanism involving the specific regulator PhaR in Haloferax mediterranei, a major PHBV production model among Haloarchaea, is not well understood. In our previous study, we showed that deletion of the phosphoenolpyruvate (PEP) synthetase-like (pps-like) gene activates the cryptic phaC genes in H. mediterranei, resulting in enhanced PHBV accumulation. In this study, we demonstrated the specific function of the PPS-like protein as a negative regulator of phaR gene expression and PHBV synthesis. Chromatin immunoprecipitation (ChIP), in situ fluorescence reporting system, and in vitro electrophoretic mobility shift assay (EMSA) showed that the PPS-like protein can bind to the promoter region of phaRP. Computational modeling revealed a high structural similarity between the rifampin phosphotransferase (RPH) protein and the PPS-like protein, which has a conserved ATP-binding domain, a His domain, and a predicted DNA-binding domain. Key residues within this unique DNA-binding domain were subsequently validated through point mutation and functional evaluations. Based on these findings, we concluded that PPS-like protein, which we now renamed as PspR, has evolved into a repressor capable of regulating the key regulator PhaR, and thereby modulating PHBV synthesis. This regulatory network (PspR-PhaR) for PHA biosynthesis is likely widespread among haloarchaea, providing a novel approach to manipulate haloarchaea as a production platform for high-yielding PHA. KEY POINTS: ⢠The repressive mechanism of a novel inhibitor PspR in the PHBV biosynthesis was demonstrated ⢠PspR is widespread among the PHA accumulating haloarchaea ⢠It is the first report of functional conversion from an enzyme to a trans-acting regulator in haloarchaea.
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Poli-Hidroxialcanoatos , Poli-Hidroxialcanoatos/metabolismo , Hidroxibutiratos , DNA , Poliésteres/metabolismoRESUMO
Hydroxyectoine is an important compatible solute that holds potential for development into a high-value chemical with broad applications. However, the traditional high-salt fermentation for hydroxyectoine production presents challenges in treating the high-salt wastewater. Here, we report the rational engineering of Halomonas salifodinae to improve the bioproduction of hydroxyectoine under lower-salt conditions. The comparative transcriptomic analysis suggested that the increased expression of ectD gene encoding ectoine hydroxylase (EctD) and the decreased expressions of genes responsible for tricarboxylic acid (TCA) cycle contributed to the increased hydroxyectoine production in H. salifodinae IM328 grown under high-salt conditions. By blocking the degradation pathway of ectoine and hydroxyectoine, enhancing the expression of ectD, and increasing the supply of 2-oxoglutarate, the engineered H. salifodinae strain HS328-YNP15 (ΔdoeA::PUP119-ectD p-gdh) produced 8.3-fold higher hydroxyectoine production than the wild-type strain and finally achieved a hydroxyectoine titer of 4.9 g/L in fed-batch fermentation without any detailed process optimization. This study shows the potential to integrate hydroxyectoine production into open unsterile fermentation process that operates under low-salinity and high-alkalinity conditions, paving the way for next-generation industrial biotechnology. KEY POINTS: ⢠Hydroxyectoine production in H. salifodinae correlates with the salinity of medium ⢠Transcriptomic analysis reveals the limiting factors for hydroxyectoine production ⢠The engineered strain produced 8.3-fold more hydroxyectoine than the wild type.
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Diamino Aminoácidos , Fermentação , Halomonas , Engenharia Metabólica , Halomonas/genética , Halomonas/metabolismo , Engenharia Metabólica/métodos , Diamino Aminoácidos/biossíntese , Diamino Aminoácidos/metabolismo , Diamino Aminoácidos/genética , Ciclo do Ácido Cítrico/genética , Perfilação da Expressão Gênica , Cloreto de Sódio/metabolismo , Salinidade , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Ácidos Cetoglutáricos/metabolismoRESUMO
Recent discovery of ectopic repeats (outside CRISPR arrays) provided unprecedented insights into the nondefense roles of CRISPR-Cas. A striking example is the addiction module CreTA (CRISPR-regulated toxin-antitoxins), where one or two (in most cases) ectopic repeats produce CRISPR-resembling antitoxic (CreA) RNAs that direct the CRISPR effector Cascade to transcriptionally repress a toxic RNA (CreT). Here, we demonstrated that CreTA repeats are extensively degenerated in sequence, with the first repeat (ψR1) being more diverged than the second one (ψR2). As a result, such addiction modules become highly specific to their physically-linked CRISPR-Cas loci, and in most cases, CreA could not harness a heterologous CRISPR-Cas to suppress its cognate toxin. We further disclosed that this specificity primarily derives from the degeneration of ψR1, and could generally be altered by modifying this repeat element. We also showed that the degenerated repeats of CreTA were insusceptible to recombination and thus more stable compared to a typical CRISPR array, which could be exploited to develop highly stable CRISPR-based tools. These data illustrated that repeat degeneration (a common feature of ectopic repeats) improves the stability and specificity of CreTA in protecting CRISPR-Cas, which could have contributed to the widespread occurrence and deep diversification of CRISPR systems.
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Antitoxinas , RNA , Sistemas CRISPR-Cas , Antitoxinas/genéticaRESUMO
As a high reactive oxygen species (ROS) and a reactive nitrogen species (RNS), peroxynitrite anion (ONOO- ) is widely present in organisms and plays influential roles in physiological and pathological processes. It is of great significance to develop effective fluorescent probes for imaging peroxynitrite variation in living systems. Herein we present a novel fluorescent probe TQC0 for monitoring ONOO- based on the iminocoumarin platform, and this probe was synthesized by the knoevenagel condensation between a dihydropyridine-salicylaldehyde derivative and 2-benzothiazole-acetonitrile, and subsequently masked with the boronate moiety. The obtained probe TQC0 exhibited a high signal-to-noise ratio (206-fold) and a quick 'turn-on' response (about 10 min) with great selectivity and sensitivity. Furthermore, the probe TQC0 was successfully applied for imaging ONOO- in living cells with low cytotoxicity.
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Corantes Fluorescentes , Ácido Peroxinitroso , Razão Sinal-Ruído , Espécies Reativas de Nitrogênio , Imagem ÓpticaRESUMO
BACKGROUND: The role of carbohydrate antigen 19-9 (CA 19-9) in response assessment among patients with intrahepatic cholangiocarcinoma (iCCA) remains unknown. The authors studied the association of the CA 19-9 response (defined as a reduction >50% from baseline) with the radiologic response and the outcome in patients with unresectable iCCA. METHODS: A prospective cohort of 422 patients who were initially diagnosed with unresectable iCCA, had baseline CA 19-9 levels ≥100 U/mL, and received treatment with systemic therapies at the authors' institution between January 2017 and December 2021 were enrolled in this study. The radiologic response was assessed using the Response Evaluation Criteria in Solid Tumors version 1.1. A landmark assessment of the CA 19-9 response and the radiologic response was performed. The associations between CA 19-9 response and imaging response, progression-free survival (PFS), and overall survival (OS) were analyzed. RESULTS: Two hundred sixty-seven patients (63.3%) had a CA 19-9 response. A CA 19-9 response was observed in 123 of 132 (93.2%) radiologic responders and in 144 of 290 (49.7%) radiologic nonresponders (p < .001). CA 19-9 responders outperformed nonresponders in median PFS (10.6 vs. 3.6 months; hazard ratio [HR], 4.8 months; 95% confidence interval [CI], 3.8-6.0 months; p < .001) and OS (21.4 vs. 6.3 months; HR, 5.3 months; 95% CI, 4.2-6.7 months; p < .001). The common independent predictors of both OS and PFS included metastasis, CA 19-9 nonresponder status, and radiologic nonresponder status in multivariable analysis. CONCLUSIONS: CA 19-9 response is a valuable addition to assess tumor response and is associated with improved outcomes in patients with iCCA. Achieving a CA 19-9 response should be one of the therapeutic objectives of patients with iCCA after systemic therapies. PLAIN LANGUAGE SUMMARY: A decline in carbohydrate antigen 19-9 levels from elevated baseline levels should be one of the therapeutic aims of patients with intrahepatic cholangiocarcinoma who are managed with systemic therapies.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Estudos Prospectivos , Colangiocarcinoma/tratamento farmacológico , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/patologia , Carboidratos/uso terapêutico , Estudos RetrospectivosRESUMO
INTRODUCTION: The UK National Haemophilia Database (NHD) collects data from all UK persons with haemophilia A with inhibitors (PwHA-I). It is well-placed to investigate patient selection, clinical outcomes, drug safety and other issues not addressed in clinical trials of emicizumab. AIMS: To determine safety, bleeding outcomes and early effects on joint health of emicizumab prophylaxis in a large, unselected cohort using national registry and patient reported Haemtrack (HT) data between 01 January 2018 and 30 September 2021. METHODS: Prospectively collected bleeding outcomes were analysed in people with ≥6 months emicizumab HT data and compared with previous treatment if available. Change in paired Haemophilia Joint Health Scores (HJHS) were analysed in a subgroup. Adverse events (AEs) reports were collected and adjudicated centrally. RESULTS: This analysis includes 117 PwHA-I. Mean annualised bleeding rate (ABR) was .32 (95% CI, .18; .39) over a median 42 months treatment with emicizumab. Within-person comparison (n = 74) demonstrated an 89% reduction in ABR after switching to emicizumab and an increase in zero treated bleed rate from 45 to 88% (p < .01). In a subgroup of 37 people, total HJHS improved in 36%, remained stable in 46% and deteriorated in 18%, with a median (IQR) within-person change of -2.0 (-9, 1.5) (p = .04). Three arterial thrombotic events were reported, two possibly drug related. Other AEs were generally non-severe and usually limited to early treatment, included cutaneous reactions (3.6%), headaches (1.4%), nausea (2.8%) and arthralgia (1.4%). CONCLUSIONS: Emicizumab prophylaxis is associated with sustained low bleeding rates and was generally well-tolerated in people with haemophilia A and inhibitors.
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Anticorpos Biespecíficos , Hemofilia A , Humanos , Hemofilia A/complicações , Hemofilia A/tratamento farmacológico , Seguimentos , Anticorpos Biespecíficos/efeitos adversos , Hemorragia/complicações , Reino Unido , Fator VIII/uso terapêuticoRESUMO
Autophagy contributes to bone homeostasis and development under physiological conditions. Although previous studies have demonstrated the induction of the autophagy machinery by endogenous glucocorticoids (GCs), the precise mechanisms involved have not yet been clarified. The current study aimed to explore the effect of a low dose of GC (10-8 M dexamethasone, Dex) on autophagy in mouse embryonic osteoblastic precursor cells (MC3T3-E1 cells) and the potential mechanisms. The results showed that 10-8 M Dex induced significant time-dependent increases in the expression and activation of serum- and glucocorticoid-induced kinase-1 (SGK1) in MC3T3-E1 cells and that these effects were accompanied by increased cell viability and decreased apoptosis. The autophagy inhibitor 3-MA significantly inhibited Dex-mediated promotion of viability. Moreover, Dex increased LC3II and Beclin-1 levels and decreased SQSTM/p62 levels in a time-dependent manner, and these effects were attenuated by pretreatment with 3-MA. Transfection of Dex-treated MC3T3-E1 cells with shRNA-SGK1 resulted in a significant reduction in cell viability and an increase in apoptosis. 3-MA further exacerbated these effects of SGK1 inhibition. Knocking down SGK1 before Dex exposure significantly reduced the phosphorylated forkhead box O3a (p-FOXO3a)/FOXO3 ratio, suppressed LC3II and Beclin-1 levels, and increased SQSTM/p62 levels in MC3T3-E1 cells, and these effects were amplified by 3-MA. In conclusion, the results revealed that low-dose GC treatment increased osteoblast viability by activating autophagy via the SGK1/FOXO3a pathway.
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Dexametasona , Glucocorticoides , Animais , Camundongos , Glucocorticoides/farmacologia , Glucocorticoides/metabolismo , Dexametasona/farmacologia , Proteína Beclina-1/metabolismo , Linhagem Celular , Transdução de Sinais , Autofagia , Osteoblastos/metabolismo , ApoptoseRESUMO
BACKGROUND. Thermal ablation combined with systemic therapy is an accepted treatment of colorectal liver oligometastases (CLOM). Consensus is lacking regarding the optimal timing of thermal ablation relative to systemic therapy. OBJECTIVE. The purpose of our study was to compare delayed and up-front thermal ablation in terms of efficacy and safety in the treatment of patients with CLOM. METHODS. This retrospective multicenter study included 440 patients (316 men, 124 women; mean age, 57.1 ± 11.1 [SD] years) with CLOM from nine hospitals between October 2009 and December 2020. Patients underwent delayed (n = 322) or up-front (n = 118) thermal ablation in combination with systemic therapy. Analyses included all patients using crude data, all patients using inverse probability treatment weighting (IPTW), and a subset of patients using propensity score matching (PSM) at a 1:1 ratio to balance baseline variables (108 matched patients for each group [i.e., delayed ablation and up-front ablation]). Patients were classified as having a low or high tumor burden score (TBS) on the basis of the number and size of the liver metastases. The primary outcome was progression-free survival (PFS); secondary outcomes included overall survival (OS), complications from ablation, and adverse events (AEs) from systemic therapy. Survival analysis used the Kaplan-Meier method. RESULTS. The median follow-up was 2.9 years. The 5-year PFS was 17.1% for delayed ablation versus 33.6% for up-front ablation in all patients and 17.9% versus 34.7% after PSM. Delayed ablation was associated with worse PFS in the crude analysis (HR = 0.62), IPTW analysis (HR = 0.66), and PSM analysis (HR = 0.62) (all p < .05). No analysis showed a significant difference in OS between delayed and up-front ablation. Crude, IPTW, and PSM analyses showed better PFS for up-front compared with delayed ablation in patients with a low TBS (HR = 0.62-0.67; all p < .05); none of these analyses showed significant difference in PFS in patients with a high TBS. Delayed ablation and up-front ablation groups showed no difference in frequency of grade III or IV ablation complications (4.7% vs 6.8%, p = .38) or grade III or IV systemic therapy AEs (12.4% vs 10.2%, p = .53). CONCLUSION. In patients with CLOM, up-front ablation achieved better PFS compared with delayed ablation, although only among patients with a low TBS. CLINICAL IMPACT. These findings could help optimize clinical implementation of thermal ablation in patients who are not candidates for surgical resection.
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Neoplasias Colorretais , Neoplasias Hepáticas , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Resultado do Tratamento , Pontuação de Propensão , Neoplasias Hepáticas/patologia , Neoplasias Colorretais/patologia , Fígado/patologiaRESUMO
Chalcogenide glasses in the Na2S-GeS2-Ga2S3 pseudoternary system were synthesized using a combination route of melt-quenching and mechanical-milling methods. First, a glass rich in germanium (90GeS2-10Ga2S3) is synthesized by melt-quenching synthesis in a silica tube sealed under vacuum. This glass is used as a precursor for the second step of mechanochemistry to explore the Na2S-GeS2-Ga2S3 pseudoternary system. By using this synthesis route, the glass-forming ability is improved as the vitreous domain is enlarged, especially for Na- and Ga-rich compositions. The as-obtained amorphous powders are characterized by Raman spectroscopy, differential scanning calorimetry, X-ray total scattering, and pair distribution function (PDF) analysis. The evolution of the Raman features observed is reproduced using density functional theory calculations. Impedance spectroscopy was performed to determine the conductivity of the new glasses. The addition of germanium sulfide to the Na2S-Ga2S3 pseudobinary system enables one to increase the conductivity by 1 order of magnitude. The highest room-temperature ionic conductivity, as measured by impedance spectroscopy, is 1.8 × 10-5 S·cm-1.
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AIMS: Activation mapping of premature atrial complexes (PACs) proves challenging due to interference by mechanical bumping and non-targeted ectopies. This study aims to compare the mapping efficacy, instant success, and long-term recurrence of catheter ablation for PACs with non-pulmonary vein (PV) and non-superior vena cava (SVC) origins between the novel dual-reference approach (DRA) and the routine single-reference approach (SRA) of mapping. METHODS AND RESULTS: Patients with symptomatic, drug-refractory PACs, or frequent residual PACs after atrial tachyarrhythmia ablation were enrolled. During activation mapping, the coronary sinus (CS) catheter was used as the only timing reference in the SRA group. In the DRA group, another catheter, which was spatially separated from the CS catheter, was used as the second reference. The timing difference between the two references was used to discriminate the targeted PACs from the uninterested rhythms. Procedural parameters and long-term recurrence were compared. A total of 188 patients (109 in SRA and 79 in DRA) were enrolled. The baseline characteristics were similar. Compared with the SRA group, the DRA group had less repeated mapping (1.2 ± 0.4 vs. 1.4 ± 0.5, P = 0.004), shorter mapping (15 ± 6 vs. 23 ± 7 min, P < 0.001) and procedural time (119 ± 28 vs. 132 ± 22 min, P = 0.001), similar procedural complication rates (3.6 vs. 3.8%, P > 0.999), higher instant success (96.2 vs. 87.2%, P = 0.039), and lower recurrence rate (15.2 vs. 29.3%, hazard ratio 1.943, P = 0.033) during a 24-month follow-up. CONCLUSION: As a novel strategy, the DRA shortens the procedural time and improves both instant and long-term success of PAC ablation, serving as a promising approach in mapping PACs with non-PV and non-SVC origins.
Assuntos
Fibrilação Atrial , Complexos Atriais Prematuros , Ablação por Cateter , Veias Pulmonares , Humanos , Fibrilação Atrial/cirurgia , Resultado do Tratamento , Veias Pulmonares/cirurgia , Complexos Atriais Prematuros/diagnóstico , Complexos Atriais Prematuros/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , RecidivaRESUMO
Bruton's tyrosine kinase (BTK) is a promising drug target for the treatment of B-cell related malignancies. Irreversible inhibition of BTK by a covalent inhibitor has been proved to be a clinically effective therapy. However, most irreversible BTK inhibitors also inhibit other kinases including JAK3 and EGFR, leading to some adverse events. Herein, we reported the structure-based design and optimization of a series of irreversible BTK inhibitors bearing the 6-amino-1,3,5-triazine scaffold. Most of the synthesized compounds demonstrated considerable BTK inhibition and improved anti-proliferative activity against Raji and Ramos cells. Among them, compound C11 exhibited potent BTK inhibition (BTK IC50 = 17.0 nM) and a desirable selectivity profile especially over EGFR. Moreover, C11 effectively blocked activation of BTK and downstream signaling, arrested the cell cycle in G0/G1 phase and induced apoptosis in Raji cells. Its irreversible binding mode was further investigated by both molecular modeling and a washout experiment. Collectively, C11 is a novel selective irreversible BTK inhibitor worthy of further in-depth research.
Assuntos
Inibidores de Proteínas Quinases , Triazinas , Inibidores de Proteínas Quinases/química , Estrutura Molecular , Relação Dose-Resposta a Droga , Tirosina Quinase da Agamaglobulinemia , Relação Estrutura-Atividade , Triazinas/farmacologia , Receptores ErbB/metabolismoRESUMO
Both estrogen receptor α (ERα) and histone deacetylases (HDACs) are valid therapeutic targets for anticancer drug development. Combination therapies using diverse ERα antagonists or degraders and HDAC inhibitors have been proven effective in endocrine-resistant ER + breast cancers based on the crosstalk between ERα and HDAC pathway. In this study, we reported the optimization of a series of methoxyphenyl- or pyridinyl- substituted tetrahydroisoquinoline-hydroxamates, which were optimized from 31, a dual ERα degrader/HDAC inhibitor previously reported by our group. Most of the synthesized compounds displayed potent ERα degradation efficacy and antiproliferative activity. Among them, A04 demonstrated the best anti-proliferation activity (MCF-7 IC50 = 1.96 µM) and HDAC6 inhibitory activity (HDAC6 IC50 = 25.96 nM), which is slightly more potent than the lead compound 31 (MCF-7 IC50 = 4.38 µM, HDAC6 IC50 = 63.03 nM). In addition, compound A04 exerted ERα-independent HDAC6-inhibiting effect without agonistic activity in endometrial cells. These results demonstrated that A04 is a novel and promising dual ERα degrader/HDAC inhibitor worthy of further development.