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Autophagy is implicated in the pathogenesis of pulmonary arterial hypertension (PAH). We aimed to investigate whether the p62-Keap1-Nrf2 pathway affects the development of PAH by mediating autophagy. A PAH rat model was established using monocrotaline (MCT). Pulmonary artery smooth muscle cells (PASMCs) were extracted, and the changes in proliferation, migration, autophagy, and oxidative stress were analyzed following overexpression or knockdown of p62. The impact of p62 on the symptoms of PAH rats was assessed by the injection of an adenovirus overexpressing p62. We found that the knockdown of p62 increased the proliferation and migration of PASMCs, elevating the oxidative stress of PASMCs and upregulating gene expression of NADPH oxidases. Co-IP assay results demonstrated that p62 interacted with Keap1. p62 knockdown enhanced Keap1 protein stability and Nrf2 ubiquitination. LC3II/I and ATG5 were expressed more often when p62 was knocked down. Treating with an inhibitor of autophagy reversed the impact of p62 knockdown on PASMCs. Nrf2 inhibitor treatment reduced the expression of Nrf2 and p62, while increasing the expression of Keap1, LC3II/I, and ATG5 in PASMCs. However, overexpressing p62 diminished mRVP, SPAP, and Fulton index in PAH rats and attenuated pulmonary vascular wall thickening. Overexpression of p62 also decreased the expression of Keap1, LC3II/I, and ATG5 and increased the nuclear expression of Nrf2 in PAH rats. Importantly, overexpression of p62 reduced oxidative stress and the NADPH oxidase expression in PAH rats. Overall, activation of the p62-Keap1-Nrf2 positive feedback signaling axis reduces the proliferation and migration of PASMCs and alleviates PAH by inhibiting autophagy and oxidative stress.
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Hipertensão Arterial Pulmonar , Animais , Ratos , Autofagia/fisiologia , Proliferação de Células , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Monocrotalina , Miócitos de Músculo Liso/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Hipertensão Arterial Pulmonar/patologia , Artéria Pulmonar/metabolismoRESUMO
BACKGROUND: Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy. METHODS: This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18-65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2-T3 vs T4), and recurrent nodal stage (N0 vs N1-N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506. FINDINGS: Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3-53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 [34%] of 68 patients) versus the standard fractionation group (39 [57%] of 68 patients; between-group difference -23% [95% CI -39 to -7]; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% [95% CI 64·4 to 84·8] vs 55·0% [43·4 to 66·6]; hazard ratio for death 0·54 [95% CI 0·33 to 0·88]; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five [7%] nasal haemorrhage) than in the standard fractionation group (16 [24%], including two [3%] nasopharyngeal necrosis, 11 [16%] nasal haemorrhage, and three [4%] temporal lobe necrosis). INTERPRETATION: Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients. FUNDING: Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.
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Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Masculino , Humanos , Feminino , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Recidiva Local de Neoplasia/radioterapia , Neoplasias Nasofaríngeas/radioterapia , HemorragiaRESUMO
Plasmonic materials are fundamental photosensitizer materials for photocatalytic reactions. Various structures, including core-shell types, satellite types, and distribution types, have been designed and prepared for the optimization of photocatalytic reactions. However, understanding the profound enhancement mechanism of various structures is still challenging. Thus, the plasmonic coverage is considered to be an index for analyzing the influence mechanism. Here, Au@Ni-MOF core-shell flower sphere-like photocatalysts are prepared, and the size of the flower sphere can be precisely regulated by varying the amount of Au. Thus, different plasmonic coverages are realized through the tuning of spheres of different sizes. The high plasmonic coverage of catalysts can enhance visible light absorption, facilitate the generation of photogenerated electron-hole pairs, and shorten the photogenerated carrier transport distance. Moreover, the exponential relationship between the photocatalytic hydrogen production performance and the plasmonic coverage can also be used as a guide for material design. As a result, a photocatalytic hydrogen production rate of 3389 µmol·g-1·h-1 is achieved in the Au@Ni-MOF sample with high plasmonic coverage, which will advance the plasmonic application in photocatalytic reactions.
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The NHC-catalyzed enantioselective [4 + 2] annulation of 9H-fluorene-1-carbaldenydes with cyclic imines was successfully developed. A series of optically enriched polycyclic dihydroisoquinolinones were synthesized in moderate to excellent yields with good to excellent enantioselectivities. In addition, this efficient method could also be amenable to the synthesis of spirocyclic compounds by using isatin-derived ketimines as the electrophiles.
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Rapid construction of functionalized aza-anthraquinones has been successfully developed via NHC-catalyzed formal [3 + 3] annulation of 2-aminoquinones with enals. This reaction features several advantages, such as readily available starting materials, mild reaction conditions, and flexible product transformations. The study on the atroposelective version of this strategy was also carried out, and several C-N axial chiral aza-anthraquinones were synthesized in moderate yields with moderate to good enantioselectivities.
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The escalating obesity epidemic and aging population have propelled metabolic dysfunction-associated steatohepatitis (MASH) to the forefront of public health concerns. The activation of FXR shows promise to combat MASH and its detrimental consequences. However, the specific alterations within the MASH-related transcriptional network remain elusive, hindering the development of more precise and effective therapeutic strategies. Through a comprehensive analysis of liver RNA-seq data from human and mouse MASH samples, we identified central perturbations within the MASH-associated transcriptional network, including disrupted cellular metabolism and mitochondrial function, decreased tissue repair capability, and increased inflammation and fibrosis. By employing integrated transcriptome profiling of diverse FXR agonists-treated mice, FXR liver-specific knockout mice, and open-source human datasets, we determined that hepatic FXR activation effectively ameliorated MASH by reversing the dysregulated metabolic and inflammatory networks implicated in MASH pathogenesis. This mitigation encompassed resolving fibrosis and reducing immune infiltration. By understanding the core regulatory network of FXR, which is directly correlated with disease severity and treatment response, we identified approximately one-third of the patients who could potentially benefit from FXR agonist therapy. A similar analysis involving intestinal RNA-seq data from FXR agonists-treated mice and FXR intestine-specific knockout mice revealed that intestinal FXR activation attenuates intestinal inflammation, and has promise in attenuating hepatic inflammation and fibrosis. Collectively, our study uncovers the intricate pathophysiological features of MASH at a transcriptional level and highlights the complex interplay between FXR activation and both MASH progression and regression. These findings contribute to precise drug development, utilization, and efficacy evaluation, ultimately aiming to improve patient outcomes.
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Fígado , Camundongos Knockout , Receptores Citoplasmáticos e Nucleares , Animais , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Humanos , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Masculino , Fígado Gorduroso/metabolismo , Fígado Gorduroso/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/patologia , TranscriptomaRESUMO
Three new polyhydroxylated spirostanol steroidal saponins, dulongenosides B-D (2-4), along with 14 known compounds, dulongenoside A (1), padelaoside B (5), parisyunnanoside G (6), polyphyllin D (7), ophiopogonin C' (8), formosanin C (9), dioscin (10), paris saponin VII (11), paris H (12), parisyunnanoside I (13), protodioscin (14), proprotogracillin (15), crustecdysone (16), and stigmasterol-3-O-ß-d-glucopyranoside (17), were isolated from the rhizomes of Paris dulongensis (Melanthiaceae). Their chemical structures were elucidated based on extensive analyses of NMR and MS data and acidic hydrolyses. The isolates were evaluated for their cytotoxicity to five human cancer cell lines (HL-60, SW480, MDA-MB-231, A549, and A549/Taxol) and the normal human bronchial epithelial cell line BEAS-2B by the MTS test. Compounds 7-12 and 14 showed cytotoxic activity, with IC50 values ranging from 0.20 to 4.35â µM. Proprotogracillin selectively inhibited A549 (IC50=0.58â µM) and A549/Taxol (IC50=0.74â µM) cells, with no significant cytotoxic activity against HL-60, SW480, MDA-MB-231, or BEAS-2B cells, with IC50 values greater than 40â µM.
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Antineoplásicos Fitogênicos , Ensaios de Seleção de Medicamentos Antitumorais , Melanthiaceae , Rizoma , Saponinas , Espirostanos , Humanos , Saponinas/isolamento & purificação , Saponinas/farmacologia , Saponinas/química , Rizoma/química , Melanthiaceae/química , Espirostanos/química , Espirostanos/isolamento & purificação , Espirostanos/farmacologia , Linhagem Celular Tumoral , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Relação Estrutura-Atividade , Sobrevivência Celular/efeitos dos fármacos , Estrutura Molecular , Conformação Molecular , Relação Dose-Resposta a DrogaRESUMO
Cladosporium spp. are known to be mycoparasites and inhibit phytopathogenic fungi. However, so far, little information is available on the impact of Cladosporium spp. on powdery mildews. Based on the morphological characteristics and molecular analysis, C. sphaerospermum was identified as a mycoparasite on the wheat powdery mildew fungus Blumeria graminis f. sp. tritici (Bgt), recently named B. graminis s. str. C. sphaerospermum was capable of preventing colony formation and conidial distribution of Bgt. The biomasses of Bgt notably decreased by 1.3, 2.2, 3.6, and 3.8 times at 2, 4, 6, and 8 days postinoculation (dpi), respectively. In addition, biomasses of C. sphaerospermum at 2, 4, 6, and 8 dpi significantly increased to 5.6, 13.9, 18.2, and 67.3 times, respectively. In vitro, C. sphaerospermum exudates significantly impaired appressorial formation of Bgt. Thus, C. sphaerospermum acts as a potential biological control agent by suppressing the formation, distribution, and development of Bgt conidia and is a viable alternative for managing the wheat powdery mildew. These results suggest that C. sphaerospermum is an antagonistic parasite of the wheat powdery mildew fungus and, hence, provide new knowledge about the biological control of phytopathogenic fungi.
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Ascomicetos , Cladosporium , Doenças das Plantas , Triticum , Ascomicetos/fisiologia , Cladosporium/fisiologia , Triticum/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Esporos Fúngicos/fisiologia , Controle Biológico de Vetores , BiomassaRESUMO
Astragaloside IV (AST) has been confirmed to have antiasthmatic effects. However, the underline mechanism is unclear. The study aimed to explore the treatment mechanism of AST based on autophagy of memory T cells. AST treatment significantly decreased the number of T effector cells in asthma mice blood and the nude mice that received AST-treated TCMs had relieved inflammation compared with the untreated group; meanwhile, we found that AST significantly decreased the autophagy level and inhibited OX40/OX40L signal pathway of lymphocytes. The results highlighted that AST regulated autophagy to inhibit differentiation of effector T-cell phenotype.
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Asma , Autofagia , Inflamação , Saponinas , Linfócitos T , Triterpenos , Animais , Saponinas/farmacologia , Asma/tratamento farmacológico , Triterpenos/farmacologia , Triterpenos/química , Camundongos , Autofagia/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Inflamação/tratamento farmacológico , Camundongos Nus , Estrutura Molecular , Transdução de Sinais/efeitos dos fármacos , Camundongos Endogâmicos BALB CRESUMO
The organic anion transporter 3 (OAT3), an important renal uptake transporter, is associated with drug-induced acute kidney injury (AKI). Screening and identifying potent OAT3 inhibitors with little toxicity in natural products, especially flavonoids, in reducing OAT3-mediated AKI is of great value. The five strongest OAT3 inhibitors from the 97 flavonoids markedly decreased aristolochic acid I-induced cytotoxicity and alleviated methotrexate-induced nephrotoxicity. The pharmacophore model clarified hydrogen bond acceptors and hydrophobic groups are the critical pharmacophores. These findings would provide valuable information in predicting the potential risks of flavonoid-containing food/herb-drug interactions and optimizing flavonoid structure to alleviate OAT3-related AKI.
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Injúria Renal Aguda , Flavonoides , Transportadores de Ânions Orgânicos Sódio-Independentes , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Transporte Biológico , Flavonoides/farmacologia , Flavonoides/química , Transportadores de Ânions Orgânicos/efeitos dos fármacos , Transportadores de Ânions Orgânicos/metabolismo , Relação Estrutura-Atividade , Transportadores de Ânions Orgânicos Sódio-Independentes/efeitos dos fármacos , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismoRESUMO
The stem bark of Aquilaria sinensis(Thymelaeaceae), with the local name of "Li-Wa-Zi-Xing", is used in traditional Yi medicine for treating chronic gastritis and other diseases. However, its active ingredients remain currently unknown. In this study, Helicobacter pylori(Hp) is used in anti-bacterial experiments to test the active compounds derived from A. sinensis stem bark. Nineteen compounds were isolated from the stem bark of A. sinensis by column chromatography, high-performance liquid chromatography, recrystallization, etc. Aquilaridiester(1) is a new lignan. The other eighteen compounds were reported before, including docosyl caffeate(2), 6-hydroxy-2-[2-(4-methoxyphenyl)ethyl]-4H-1-benzopyran-4-one(3), qinanone A(4), 6-hydroxy-2-(2-phenylethyl)chromone(5), 6-hydroxy-2-[2-(3-hydroxy-4-methoxyphenyl)ethyl]-4H-1-benzopyran-4-one(6), 6-hydroxy-2-[2-(3-methoxy-4-hydroxyphenyl)ethyl]-4H-1-benzopyran-4-one(7), 6-hydroxy-2-[2-(3,4-dimethoxyphenyl)ethyl]chromone(8), 6-hydroxy-2-[(1E)-2-(4-hydroxy-3-methoxyphenyl)ethenyl]-4H-1-benzopyran-4-one(9), genkwanin(10), 5-hydroxy-2-(4-hydroxy-3,5-dimethoxyphenyl)-7-methoxy-4H-1-benzopyran-4-one(11), 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone(12),(+)-syringaresinol(13), zhebeiresinol(14), aquilarin A(15), caruilignan D(16),(-)-ficusal(17), pistaciamide(18), and protocatechuic acid(19). The anti-bacterial results show that compounds 2-7, 10-11, and 13 have inhibitory activity against Hp. Among them, 6-hydroxy-2-(2-phenylethyl)chromone(5) and 6-hydroxy-2-[2-(3-methoxy-4-hydroxyphenyl)ethyl]-4H-benzopyran-4-one(7) have superior inhibitory effects on Hp to others, with the same minimum inhibitory concentration(MIC) of 6.25 µmol·L~(-1). The 2-(2-phenylethyl)chromones are the major active ingredients in A. sinensis stem bark.
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Antibacterianos , Helicobacter pylori , Testes de Sensibilidade Microbiana , Casca de Planta , Thymelaeaceae , Helicobacter pylori/efeitos dos fármacos , Casca de Planta/química , Antibacterianos/farmacologia , Antibacterianos/química , Thymelaeaceae/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Estrutura Molecular , Caules de Planta/químicaRESUMO
The stability of platinum-based alloy catalysts is crucial for the future development of proton exchange membrane fuel cells, considering the potential dissolution of transition metals under complex operating conditions. Here, we report on a Rh-doped Pt3Co alloy that exhibits strong interatomic interactions, thereby enhancing the durability of fuel cells. The Rh-Pt3Co/C catalyst demonstrates exceptional catalytic activity for oxygen reduction reactions (ORR) (1.31â A mgPt -1 at 0.9â V vs. the reversible hydrogen electrode (RHE) and maintaining 92 % of its mass activity after 170,000 potential cycles). Long-term testing has shown direct inhibition of Co dissolution in Rh-Pt3Co/C. Furthermore, tests on proton exchange membrane fuel cells (PEMFC) have shown excellent performance and long-term durability with low Pt loading. After 50,000â cycles, there was no voltage loss at 0.8â A cm-2 for Rh-Pt3Co/C, while Pt3Co/C experienced a loss of 200â mV. Theoretical calculations suggest that introducing transition metal atoms through doping creates a stronger compressive strain, which in turn leads to increased catalytic activity. Additionally, Rh doping increases the energy barrier for Co diffusion in the bulk phase, while also raising the vacancy formation energy of the surface Pt. This ensures the long-term stability of the alloy over the course of the cycle.
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OBJECTIVES: To summarize the clinical characteristics and genetic variations in children with cystic fibrosis (CF) primarily presenting with pseudo-Bartter syndrome (CF-PBS), with the aim to enhance understanding of this disorder. METHODS: A retrospective analysis was performed on the clinical data of three children who were diagnosed with CF-PBS in Hunan Children's Hospital from January 2018 to August 2023, and a literature review was performed. RESULTS: All three children had the onset of the disease in infancy. Tests after admission showed hyponatremia, hypokalemia, hypochloremia, and metabolic alkalosis, and genetic testing showed the presence of compound heterozygous mutation in the CFTR gene. All three children were diagnosed with CF. Literature review obtained 33 Chinese children with CF-PBS, with an age of onset of 1-36 months and an age of diagnosis of 3-144 months. Among these children, there were 29 children with recurrent respiratory infection or persistent pneumonia (88%), 26 with malnutrition (79%), 23 with developmental retardation (70%), and 18 with pancreatitis or extrapancreatic insufficiency (55%). Genetic testing showed that c.2909G>A was the most common mutation site of the CFTR gene, with a frequency of allelic variation of 23% (15/66). CONCLUSIONS: CF may have no typical respiratory symptoms in the early stage. The possibility of CF-PBS should be considered for infants with recurrent hyponatremia, hypokalemia, hypochloremia, and metabolic alkalosis, especially those with malnutrition and developmental retardation. CFTR genetic testing should be performed as soon as possible to help with the diagnosis of CF.
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Síndrome de Bartter , Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Mutação , Humanos , Fibrose Cística/genética , Fibrose Cística/complicações , Masculino , Feminino , Lactente , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Síndrome de Bartter/genética , Síndrome de Bartter/diagnóstico , Síndrome de Bartter/complicações , Pré-Escolar , Criança , Estudos RetrospectivosRESUMO
Upconversion (UC) is a fascinating anti-Stokes-like optical process with promising applications in diverse fields. However, known UC mechanisms are mainly based on direct energy transfer between metal ions, which constrains the designability and tunability of the structures and properties. Here, we synthesize two types of Ln8L12-type (Ln for lanthanide ion; L for organic ligand L1 or L2R/S) lanthanide-organic complexes with assembly induced excited-multimer states. The Yb8(L2R/S)12 assembly exhibits upconverted multimer green fluorescence under 980 nm excitation through a cooperative sensitization process. Furthermore, upconverted red emission from Eu3+ on the heterometallic (Yb/Eu)8L12 assemblies is also realized via excited-multimer mediated energy relay. Our findings demonstrate a new strategy for designing UC materials, which is crucial for exploiting photofunctions of multicomponent lanthanide-organic complexes.
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The combination of immunotherapy and antiangiogenic agents for the treatment of refractory solid tumor has not been well investigated. Thus, our study aimed to evaluate the efficacy and safety of a new regimen of anlotinib plus PD-1 inhibitor to treat refractory solid tumor. APICAL-RST is an investigator-initiated, open-label, single-arm, phase II trial in patients with heavily treated, refractory, metastatic solid tumor. Eligible patients experienced disease progression during prior therapy without further effective regimen. All patients received anlotinib and PD-1 inhibitor. The primary endpoints were objective response and disease control rates. The secondary endpoints included the ratio of progression-free survival 2 (PFS2)/PFS1, overall survival (OS) and safety. Forty-one patients were recruited in our study; 9 patients achieved a confirmed partial response and 21 patients had stable disease. Objective response rate and disease control rate were 22.0% and 73.2% in the intention-to-treat cohort, and 24.3% and 81.1% in the efficacy-evaluable cohort, respectively. A total of 63.4% (95% confidence interval [CI]: 46.9%-77.4%) of the patients (26/41) presented PFS2/PFS1 >1.3. The median OS was 16.8 months (range: 8.23-24.4), and the 12- and 36-month OS rates were 62.8% and 28.9%, respectively. No significant association was observed between concomitant mutation and efficacy. Thirty-one (75.6%) patients experienced at least one treatment-related adverse event. The most common adverse events were hypothyroidism, hand-foot syndrome and malaise. This phase II trial showed that anlotinib plus PD-1 inhibitor exhibits favorable efficacy and tolerability in patients with refractory solid tumor.
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Neoplasias , Quinolinas , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias/tratamento farmacológico , Indóis/efeitos adversos , Quinolinas/efeitos adversosRESUMO
The vigorous development of efficient platinum group metal-free catalysts is considerably important to facilitate the universal application of proton exchange membrane fuel cells. Although nitrogen-coordinated atomic iron intercalated in carbon matrix (Fe-N-C) catalysts exhibit promising catalytic activity, the performance in fuel cells, especially the short lifetime, remains an obstacle. Herein, a highly-active Fe-N-C catalyst with a power density of >1 w cm-2 and prolonged discharge stability with a current density of 357 mA cm-2 after 40 h of constant voltage discharge at 0.7 V in H2 -O2 fuel cells using a controllable and efficient N-C coating strategy is developed. It is clarified that a thicker N-C coating may be more favorable to enhance the stability of Fe-N-C catalysts at the expense of their catalytic activity. The stability enhancement mechanism of the N-C coating strategy is proven to be the synergistic effect of reduced carbon corrosion and iron loss. It is believed that these findings can contribute to the development of Fe-N-C catalysts with high activity and long lifetimes.
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OBJECTIVES: The genus Streptococcus contains species of important zoonotic pathogens such as those that cause bovine mastitis. Unfortunately, many Streptococcus species have developed antibiotic resistance. Phage lysins are considered promising alternatives to antibiotics because it is difficult for bacteria to develop lysin resistance. However, there remains a lack of phage lysin resources for the treatment of streptococci-induced mastitis. METHODS: We identified the prophage lysin Lys0859 from the genome of the Streptococcus suis SS0859 strain. Lys0859 was subsequently characterized to determine its host range, MIC, bactericidal activity in milk, and ability to clear biofilms in vitro. Finally, to determine the effects of Lys0859 on the treatment of both bovine mastitis and S. suis infection in vivo, we established models of Streptococcus agalactiae ATCC 13813-induced mastitis and S. suis serotype 2 SC19 systemic infection. RESULTS: Our results demonstrate that Lys0859 possesses broad-spectrum lytic activity against Streptococcus and Staphylococcus species isolated from animals with bovine mastitis and 15 serotypes of S. suis isolated from swine. Intramammary and intramuscular injection of Lys0859 reduced the number of bacteria in mammary tissue by 3.75 and 1.45 logs compared with the PBS group, respectively. Furthermore, 100 µg/mouse of Lys0859 administered intraperitoneally at 1 h post-infection protected 83.3% (5/6) of mice from a lethal dose of S. suis infection. CONCLUSIONS: Overall, our results enhance the understanding and development of new strategies to combat both streptococci-induced mastitis and S. suis infection.
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Bacteriófagos , Mastite Bovina , Infecções Estreptocócicas , Fagos de Streptococcus , Streptococcus suis , Feminino , Bovinos , Animais , Suínos , Camundongos , Humanos , Prófagos/genética , Mastite Bovina/tratamento farmacológico , Antibacterianos/farmacologia , Infecções Estreptocócicas/microbiologiaRESUMO
Patterns of hepatitis B virus reactivation (HBV-R) in HBsAg (-)/HBcAb (+) patients with B-cell non-Hodgkin lymphoma (NHL) receiving rituximab based immunochemotherapy have not been well described. The retrospective study included 222 HBsAg (-)/HBcAb (+) NHL patients as training cohort and 127 cases as validation cohort. The incidence of HBV-R in HBsAg (-)/HBcAb (+) B-cell NHL patients was 6.3% (14/222), of which that in HBsAg (-)/HBsAb (-)/HBeAg (-)/HBeAb (+)/HBcAb (+) population was 23.7% (9/38). Multivariate analysis showed that HBsAg (-)/HBsAb (-)/HBeAg (-)/HBeAb (+)/HBcAb (+) correlated with a high risk of HBV-R in B-cell lymphoma patients (training phase hazard ratio [HR], 10.123; 95% confidence interval [CI], 3.389-30.239; p < 0.001; validation phase HR, 18.619; 95% CI, 1.684-205.906; p = 0.017; combined HR, 12.264; 95% CI, 4.529-33.207; p < 0.001). In the training cohort, the mortality rate of HBsAg (-)/HBcAb (+) B-cell NHL caused by HBV-R was 14.3% (2/14) while that for HBV reactivated HBsAg (-)/HBsAb (-)/HBeAg (-)/HBeAb (+)/HBcAb (+) population was up to 44.4% (4/9). As a high incidence of HBV-R and high mortality after HBV-R was found in HBsAg (-)/HBsAb (-)/HBcAb (+)/HBeAg (-)/HBeAb (+) patients with B-cell NHL receiving rituximab based immunochemotherapy, prophylactic antiviral therapy is recommended for these patients.
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Hepatite B , Linfoma de Células B , Humanos , Rituximab/uso terapêutico , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Estudos Retrospectivos , Ativação Viral , Hepatite B/epidemiologia , Vírus da Hepatite B , Anticorpos Anti-Hepatite B , Linfoma de Células B/induzido quimicamente , Linfoma de Células B/tratamento farmacológicoRESUMO
O3-type Fe/Mn-based layered oxide cathode materials with abundant reserves have a promising prospect in sodium-ion batteries. However, the electrochemical reversibility of most O3-type Fe/Mn-based oxide cathode materials is still not high enough. Herein, the effect of different Cu contents on the electrochemical properties of O3-NaFe0.50 Mn0.50 O2 materials is systematically investigated. The as-prepared NaFe0.30 Mn0.50 Cu0.20 O2 cathode achieves the synergistic optimization of the interface and bulk phase. It shows superior electrochemical performance, with an initial discharge specific capacity of 114â mAh g-1 at 0.1â C, a capacity retention rate of 94 % after 100â cycles at 0.5â C, and excellent chemical stability in air and water. In addition, the sodium ion full battery based on NaFe0.30 Mn0.50 Cu0.20 O2 cathode and hard carbon anode has a capacity retention rate of 81 % after 100â cycles. This research provides a useful approach for the preparation of low-cost and high-performance O3-type layered cathode materials.
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The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) dramatically improve the clinical outcomes of non-small cell lung cancer (NSCLC) patients harboring EGFR -sensitive mutations. Despite the remarkable efficacy of first-and second-generation EGFR TKIs, disease relapse is inevitable. EGFR T790M mutation is a primary contributor to the acquired resistance to first- and second-generation EGFR TKIs. Osimertinib, which is an irreversible third-generation EGFR TKI, was designed for EGFR -activating mutations as well as the EGFR T790M mutation in patients with advanced NSCLC and has demonstrated a convincing efficacy. However, acquired resistance to osimertinib after treatment inevitably occurs. The acquired resistance mechanisms to osimertinib are highly complicated and not fully understood, encompassing EGFR -dependent as well as EGFR -independent mechanisms. Treatment approaches for patients progressing from osimertinib have not been established. We present a case of a stage IV lung adenocarcinoma patient harboring EGFR L858R, acquired T790M after treatment with first-line gefitinib. She then acquired a new EML4-ALK gene fusion after treatment with osimertinib. A combination targeted therapy of osimertinib plus alectinib was initiated, with a progression-free survival of 5 months without any serious adverse reaction. After disease progression, EGFR C797S in cis was detected with a loss of the EML4-ALK fusion by targeted next-generation sequencing. Then therapy was changed to pemetrexed combined with bevacizumab plus camrelizumab, but no obvious effect was observed. The patient had achieved an overall survival of 31 months. As far as we know, this was the first reported case that an EGFR -mutant NSCLC patient-acquired ALK fusion mediating resistance to osimertinib, and sequential EGFR C797S mutation mediating resistance to combined targeted therapy with osimertinib and alectinib. Our case shows that EML4-ALK fusion is a rare but critical resistance mechanism to osimertinib, and C797S mutation in cis may be an underlying mechanism of acquired resistance mutation in double TKIs therapy. Furthermore, molecular detection and rebiopsy play important roles in the selection of therapeutic strategies when the disease progresses.