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BACKGROUND: Previous studies implied that local M2 polarization of macrophage promoted mucosal edema and exacerbated TH2 type inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP). However, the specific pathogenic role of M2 macrophages and the intrinsic regulators in the development of CRS remains elusive. OBJECTIVE: We sought to investigate the regulatory role of SIRT5 in the polarization of M2 macrophages and its potential contribution to the development of CRSwNP. METHODS: Real-time reverse transcription-quantitative PCR and Western blot analyses were performed to examine the expression levels of SIRT5 and markers of M2 macrophages in sinonasal mucosa samples obtained from both CRS and control groups. Wild-type and Sirt5-knockout mice were used to establish a nasal polyp model with TH2 inflammation and to investigate the effects of SIRT5 in macrophage on disease development. Furthermore, in vitro experiments were conducted to elucidate the regulatory role of SIRT5 in polarization of M2 macrophages. RESULTS: Clinical investigations showed that SIRT5 was highly expressed and positively correlated with M2 macrophage markers in eosinophilic polyps. The expression of SIRT5 in M2 macrophages was found to contribute to the development of the disease, which was impaired in Sirt5-deficient mice. Mechanistically, SIRT5 was shown to enhance the alternative polarization of macrophages by promoting glutaminolysis. CONCLUSIONS: SIRT5 plays a crucial role in promoting the development of CRSwNP by supporting alternative polarization of macrophages, thus providing a potential target for CRSwNP interventions.
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The Coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains a global threat, exacerbated by the emergence of viral variants. Two variants of SARS-CoV-2, Omicron BA.2.75 and BA.5, led to global infection peaks between May 2022 and May 2023, yet their precise characteristics in pathogenesis are not well understood. In this study, we compared these two Omicron sublineages with the previously dominant Delta variant using a human angiotensin-converting enzyme 2 knock-in mouse model. As expected, Delta exhibited higher viral replication in the lung and brain than both Omicron sublineages which induced less severe lung damage and immune activation. In contrast, the Omicron variants especially BA.5.2 showed a propensity for cellular proliferation and developmental pathways. Both Delta and BA.5.2 variants, but not BA.2.75, led to decreased pulmonary lymphocytes, indicating differential adaptive immune response. Neuroinvasiveness was shared with all strains, accompanied by vascular abnormalities, synaptic injury, and loss of astrocytes. However, Immunostaining assays and transcriptomic analysis showed that BA.5.2 displayed stronger immune suppression and neurodegeneration, while BA.2.75 exhibited more similar characteristics to Delta in the cortex. Such differentially infectious features could be partially attributed to the weakened interaction between Omicron Spike protein and host proteomes decoded via co-immunoprecipitation followed by mass spectrometry in neuronal cells. Our present study supports attenuated replication and pathogenicity of Omicron variants but also highlights their newly infectious characteristics in the lung and brain, especially with BA.5.2 demonstrating enhanced immune evasion and neural damage that could exacerbate neurological sequelae.
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COVID-19 , Enfermedades Transmisibles , Enfermedades del Sistema Nervioso , Animales , Ratones , Humanos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genéticaRESUMEN
Single-crystal membranes (SCMs) show great promise in the fields of sensors, light-emitting diodes, and photodetection. However, the growth of a large-area single-crystal membranes is challenging. We report a new organic-inorganic SCMs [HCMA]2CuBr4 (HCMA = cyclohexanemethylamine) crystallized at the gas-liquid interface. It also has low-temperature ferromagnetic order, high-temperature dielectric anomalies, and narrow band gap indirect semiconductor properties. Specifically, the reversible phase transition of the compound occurs at 350/341 K on cooling/heating and exhibits dielectric anomalies and stable switching performance near the phase transition temperature. The ferromagnetic exchange interaction in the inorganic octahedra and the organic layer enables ferromagnetic ordering at low-temperature 10 K. Finally, the single crystal exhibits an indirect semiconducting property with a narrow band gap of 0.99 eV. Such rich multichannel physical properties make it a potential application in photodetection, information storage and sensors.
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A K-Eu bimetallic ammonium metal-nitrate three-dimensional (3D) framework incorporating R-N-methyl-3-hydroxyquinuclidine, (RM3HQ)2KEu(NO3)6 (RM3HQ = R-N-methyl-3-hydroxyquinuclidine, 1), was characterized and reported. Distinguishing from the former hybrid rare-earth double perovskites, 1 adopts a mixed corner- and face-sharing K+/Eu3+-centered polyhedral connectivity to form a 3D inorganic framework, showing a rare (6, 6)-connected ion topology with a 66 framework. Notably, 1 exhibits clear phase transition, and the switchable thermodynamic behavior is confirmed by variable-temperature dielectric measurements and second-harmonic generation response. Moreover, 1 also shows photoluminescence properties. The activator Eu3+ plays a crucial role in this process, leading to a significant narrow emission at 592 nm with a photoluminescence quantum yield (PLQY) of 20.76%. The fluorescence lifetime (FLT) of 1 is 4.32 ms. This finding enriches the bimetallic hybrid system for potential electronic and/or luminescence applications.
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OBJECTIVE: This review aims to summarize existing evidence on the adverse pregnancy outcomes and seizure control effects of using lamotrigine (LTG) monotherapy in pregnancy women with epilepsy (WWE) during pregnancy. METHODS: A comprehensive search was conducted in various databases including Cochrane, Web of Science, CBM, PubMed, Embase, CNKI, and Pregnancy Registration Center databases to identify relevant studies. The search was concluded up to January 2024. Studies comparing LTG with other antiseizure medications (ASMs) for treating epilepsy in pregnant women were included, with no language or regional restrictions. RESULTS: A total of 19 studies were included for analysis, with 16 studies reporting adverse pregnancy outcomes and 6 studies reporting seizure control outcomes. Meta-analysis showed that compared to monotherapy with carbamazepine (CBZ), sodium valproate (VPA), and levetiracetam (LEV), LTG monotherapy had a slightly weaker ability to control seizures during pregnancy, with ORs and 95 %CIs of 0.65 (0.57-0.75; CBZ), 0.50 (0.32-0.79; VPA), and 0.55 (0.36-0.84; LEV). Regarding adverse pregnancy outcomes, the occurrence rate of LTG monotherapy was significantly lower than that of CBZ, VPA, phenytoin (PHT), and phenobarbital (PHB), with ORs and 95 %CIs ranging from 0.30 (0.25-0.35; VPA) to 0.68 (0.56-0.81; CBZ). CONCLUSION: Based on meta-analysis, LTG and LEV appear to be preferred medications for controlling seizures during pregnancy. This review provides further support for the use of LTG monotherapy in pregnant WWE, building upon existing evidence for clinical practitioners.
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Anticonvulsivantes , Epilepsia , Lamotrigina , Complicaciones del Embarazo , Convulsiones , Humanos , Embarazo , Femenino , Anticonvulsivantes/efectos adversos , Anticonvulsivantes/uso terapéutico , Lamotrigina/uso terapéutico , Lamotrigina/efectos adversos , Complicaciones del Embarazo/tratamiento farmacológico , Convulsiones/tratamiento farmacológico , Convulsiones/inducido químicamente , Epilepsia/tratamiento farmacológico , Resultado del Embarazo/epidemiologíaRESUMEN
Seven new 4-hydroxy-6-phenyl-2H-pyran-2-one (HPPO) derived meroterpenoids, 1-methyl-12a,12b-epoxyarisugacin M (1), 1-methyl-4a,12b-epoxyarisugacin M (2), 2,3-dihydroxy-3,4a-epoxy-12a-dehydroxyisoterreulactone A (3), 2-hydroxy-12a-dehydroxyisoterreulactone A (4), 3'-demethoxyterritrems B' (5), 4a-hydroxyarisugacin P (6), and 1-epi-arisugacin H (7), together with two known analogues (8 and 9), were isolated from the marine-derived fungal strain Penicillium sp. SCSIO 41691. Their structures were elucidated by spectroscopic methods, and the absolute configurations of compounds 1 and 3 were determined by single-crystal X-ray diffraction. Among them, 1 and 2 had a unique methyl migration in the basic meroterpenoid skeleton with a 12a,12b-epoxy or 4a,12b-epoxy group, and 3 was a highly oxygenated HPPO-derived meroterpenoid featuring a rare 6/5/6/6/6/6 hexacyclic system with a 3,4a-epoxy group. Biologically, 5 exhibited inhibitory activity against lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells with an IC50 value of 21 µM, more potent than the positive control indomethacin.
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Penicillium , Terpenos , Penicillium/química , Terpenos/farmacología , Terpenos/química , Terpenos/aislamiento & purificación , Estructura Molecular , Animales , Ratones , Células RAW 264.7 , Óxido Nítrico/biosíntesis , Cristalografía por Rayos X , Biología Marina , Lipopolisacáridos/farmacologíaRESUMEN
BACKGROUND: This study aimed to analyze the effect of proximal neck angulation on the biomechanical indices of abdominal aortic aneurysms (AAA) and to investigate its impact on the risk of AAA rupture. METHODS: CT angiography (CTA) data of patients with AAA from January 2015 to January 2022 were collected. Patients were divided into three groups based on the angle of the proximal neck: Group A (â ß ≤ 30°), Group B (30°<â ß ≤ 60°), and Group C (â ß > 60°). Biomechanical indices related to the rupture risk of AAA were analyzed using computational fluid dynamics modeling (CFD-Post) based on the collected data. RESULTS: Group A showed slight turbulence in the AAA lumen with a mixed laminar flow pattern. Group B had a regular low-speed eddy line characterized by cross-flow dominated by lumen blood flow and turbulence. In Group C, a few turbulent lines appeared at the proximal neck, accompanied by eddy currents in the lumen expansion area following the AAA shape. Significant differences were found in peak wall stress, shear stress, and the maximum blood flow velocity impact among the three groups. The maximum blood flow velocity at the angle of the proximal neck impact indicated the influence of the proximal neck angle on the blood flow state in the lumen. CONCLUSION: As the angle of the proximal neck increased, it caused stronger eddy currents and turbulent blood flow due to a high-speed area near the neck. The region with the largest diameter in the abdominal aortic aneurysm was prone to the highest stress, indicating a higher risk of rupture. The corner of the proximal neck experienced the greatest shear stress, potentially leading to endothelial injury and further enlargement of the aneurysm.
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BACKGROUND: The dysfunction of complement factor H (CFH), the main soluble complement negative regulator, potentiates various complement-induced renal injuries. However, insights into the underlying mechanism of CFH dysfunction remain limited. In this study, we investigated whether extracellular protease-mediated degradation accounts for CFH dysfunction in complement-mediated renal injuries. METHODS: An unbiased interactome of lupus mice kidneys identified CFH-binding protease. In vitro cleavage assay clarified CFH degradation. Pristane-induced SLE or renal ischemia-reperfusion (I/R) injury models were used in wild-type and ADAMTS7-/- mice. RESULTS: We identified the metalloprotease ADAMTS7 as a CFH-binding protein in lupus kidneys. Moreover, the upregulation of ADAMTS7 correlated with CFH reduction in both lupus mice and patients. Mechanistically, ADAMTS7 is directly bound to CFH complement control protein (CCP) 1-4 domain and degraded CCP 1-7 domain through multiple cleavages. In mice with lupus nephritis or renal I/R injury, ADAMTS7 deficiency alleviated complement activation and related renal pathologies, but without affecting complement-mediated bactericidal activity. Adeno-associated virus-mediated CFH silencing compromised these protective effects of ADAMTS7 knockout against complement-mediated renal injuries in vivo. CONCLUSION: ADAMTS7-mediated CFH degradation potentiates complement activation and related renal injuries. ADAMTS7 would be a promising anticomplement therapeutic target that does not increase bacterial infection risk.
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Factor H de Complemento , Nefritis Lúpica , Ratones , Animales , Proteína ADAMTS7 , Factor H de Complemento/metabolismo , Riñón/metabolismo , Activación de ComplementoRESUMEN
OBJECTIVE: Turner syndrome (TS) has an increased predisposition to ischaemic heart disease and the status of coronary microcirculation in TS is largely unknown. This study aims to evaluate myocardial microvascular function in TS using first-pass magnetic resonance perfusion imaging and determine significant risk factors contributing to microvascular dysfunction in the early stage. DESIGN: Perspective cohort study. PATIENTS: The study cohort consisted of 67 children and youth with TS and 32 age- and gender-matched controls. Measurements Clinical characteristics, left ventricle (LV) volume and function and cardiovascular magnetic resonance-derived myocardial perfusion parameters were assessed. Univariable and multivariable linear regression analyses were performed to assess the potential risk factors for microvascular dysfunction. RESULT: Microvascular perfusion decreased in TS in global and segmented myocardium as reflected in the lower upslopecor and maximum signal intensity (MaxSI) of LV myocardium compared to controls. Multivariable linear regression analysis indicated that age (ß = -0.107, 95% confidence interval [CI] = -0.201 to -0.013, p = .026) and being overweight/obese (ß = -1.155, CI = -2.134 to -0.176, p = .021) were independent impact factors of microvascular dysfunction. Subgroup analysis showed the upslopecor of older patients with TS decreased more significantly compared with that of normal controls. Upslopecor and MaxSI were lower in overweight/obese patients with TS than in patients with normal body mass index (BMI) and controls. CONCLUSION: Myocardial microvascular dysfunction can occur in children and youth patients with TS. Age and overweight/obesity were the independent risk factors of microvascular dysfunction, which imply the importance of lowering BMI for the prevention of coronary heart disease in young TS population.
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Isquemia Miocárdica , Imagen de Perfusión Miocárdica , Síndrome de Turner , Humanos , Adolescente , Niño , Imagen de Perfusión Miocárdica/métodos , Sobrepeso , Estudios de Cohortes , Circulación Coronaria , Imagen por Resonancia Magnética , Factores de Riesgo , Obesidad , Valor Predictivo de las Pruebas , Espectroscopía de Resonancia MagnéticaRESUMEN
Colorectal cancer (CRC) is one of the main malignancies that seriously threaten human health. Considering the high mortality and morbidity associated with this disease, even surgical resection and chemotherapy may not be sufficient in certain cases. This study aimed to explore the molecular mechanisms of miR-138-5p in regulating CRC progression. Quantitative reverse transcriptase polymerase chain reaction and western blot were performed to assess the levels of mRNA and proteins, including miR-138-5p, leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5), SP1, ß-catenin, cyclin D1, and c-myc. The bioactivities of LoVo and HCT116 cells were assessed via MTT assay, flow cytometry, and transwell assay. StarBase was used to identify the downstream targets of genes. Double luciferase reporter and RIP assays revealed the direct binding of miR-138-5p to SP1 and of SP1 to LGR5. Our results illustrated that miR-138-5p was downregulated in CRC and its knockdown accelerated CRC progression. Conversely, SP1 was upregulated in CRC and its knockdown inhibited CRC progression. SP1 is also targeted by miR-138-5p and binds to LGR5. This study showed that miR-138-5p inhibits LoVo and HCT116 cell proliferation, migration, and invasion. Overall, miR-138-5p regulates CRC progression and promotes apoptosis via the SP1/LGR5 axis. This study indicates that miR-138-5p is involved in regulating CRC progression.
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Neoplasias Colorrectales , MicroARNs , Humanos , Western Blotting , Línea Celular Tumoral , Proliferación Celular/genética , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica , Células HCT116 , MicroARNs/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Factor de Transcripción Sp1/genética , Factor de Transcripción Sp1/metabolismoRESUMEN
Millepachine, a bioactive natural product isolated from the seeds of Millettia pachycarpa, is reported to display potential antitumor activity. In this study, novel indole-containing hybrids derived from millepachine were designed, synthesized and evaluated for their antitumor activities. Among all the compounds, compound 14b exhibited the most potent cytotoxic activity against five kinds of human cancer cell lines, with IC50 values ranging from 0.022 to 0.074 µM, making it almost 100 times more active than millepachine. Valuable structure-activity relationships (SARs) were obtained. Furthermore, the mechanism studies showed that compound 14b induced cell-cycle arrest at the G2/M phase by inhibiting tubulin polymerization and further induced cell apoptosis through reactive oxygen species (ROS) accumulation and mitochondrial membrane potential (MMP) collapse. In addition, the low cytotoxicity toward normal human cells and equivalent sensitivity towards drug-resistant cells of compound 14b highlighted its potential for the development of antitumor drugs.
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Antineoplásicos , Chalconas , Humanos , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Chalconas/farmacología , Antineoplásicos/farmacología , Relación Estructura-Actividad , Apoptosis , Indoles/farmacología , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacología , Línea Celular TumoralRESUMEN
BACKGROUND: Rezvilutamide, a novel androgen-receptor inhibitor with low blood-brain barrier penetration, has shown potent antitumour activity against metastatic castration-resistant prostate cancer. In this study, we aimed to evaluate the efficacy and safety of rezvilutamide versus bicalutamide in combination with androgen-deprivation therapy (ADT) for high-volume, metastatic, hormone-sensitive prostate cancer. METHODS: CHART is a randomised, open-label, phase 3 study done at 72 hospitals in China, Poland, Czech Republic, and Bulgaria. Eligible patients were aged 18 years or older, had an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and had high-volume metastatic, hormone-sensitive prostate cancer. Previous chemotherapy or other localised treatment for prostate cancer were not allowed. Patients were randomly assigned (1:1) to receive ADT plus either rezvilutamide (240 mg) or bicalutamide (50 mg) orally once daily. Randomisation was done via an interactive response technology system (block size of four) and stratified according to ECOG performance status and presence of visceral metastasis (excluding lymph nodes). Herein, we present the results of the preplanned interim analyses for the two co-primary endpoints of radiographic progression-free survival assessed by a blinded independent review committee and overall survival in the intention-to-treat population. Safety was assessed in all patients who received at least one dose of study medication. This study is ongoing, but is closed to recruitment. This trial is registered with ClinicalTrials.gov, NCT03520478. FINDINGS: Between June 28, 2018, and Aug 6, 2020, 792 patients were screened and 654 patients were randomly assigned to receive rezvilutamide plus ADT (n=326) or bicalutamide plus ADT (n=328). At the preplanned interim analysis for radiographic progression-free survival (data cutoff May 16, 2021), the median follow-up duration was 21·2 months (IQR 16·6-25·8). Rezvilutamide significantly improved radiographic progression-free survival compared with bicalutamide (median radiographic progression-free survival not reached [95% CI not reached-not reached] vs 25·1 months [95% CI 15·7-not reached]; hazard ratio [HR] 0·44 [95% CI 0·33-0·58]; p<0·0001). At the preplanned interim analysis for overall survival (data cutoff Feb 28, 2022), the median follow-up duration was 29·3 months (IQR 21·0-33·3). Rezvilutamide significantly improved overall survival compared with bicalutamide (HR 0·58 [95% CI 0·44-0·77]; p=0·0001; median overall survival was not reached [95% CI not reached-not reached] vs not reached [36·2-not reached]). The most common grade 3 or worse adverse events of any cause in the safety population were hypertension (26 [8%] of 323 patients in the rezvilutamide group vs 24 [7%] of 324 patients in the bicalutamide group), hypertriglyceridaemia (24 [7%] vs seven [2%]), increased weight (20 [6%] vs 12 [4%]), anaemia (12 [4%] vs 16 [5%]), and hypokalaemia (11 [3%] vs four [1%]). Serious adverse events were reported in 90 (28%) of 323 patients in the rezvilutamide group and 69 (21%) of 324 patients in the bicalutamide group. No treatment-related deaths occurred in patients in the rezvilutamide group; one treatment-related death of unknown specific cause (<1%) occurred in the bicalutamide group. INTERPRETATION: In the two interim analyses, rezvilutamide plus ADT significantly improved radiographic progression-free survival and overall survival compared with bicalutamide plus ADT in patients with high-volume, metastatic, hormone-sensitive prostate cancer, with a tolerable safety profile. FUNDING: Jiangsu Hengrui Pharmaceuticals.
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Antagonistas de Andrógenos , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Próstata , Antagonistas de Andrógenos/efectos adversos , Andrógenos , Anilidas , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Supervivencia sin Enfermedad , Humanos , Masculino , Nitrilos , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Compuestos de TosiloRESUMEN
BACKGROUND: Antagonizing the androgen-receptor (AR) pathway is an effective treatment strategy for patients with metastatic castration-resistant prostate cancer (CRPC). Here, we report the results of a first-in-human phase 1/2 study which assessed the safety, pharmacokinetics, and activity of SHR3680 (a novel AR antagonist) in patients with metastatic CRPC. METHODS: This phase 1/2 study enrolled patients with progressive metastatic CRPC who had not been previously treated with novel AR-targeted agents. In the phase 1 dose-escalation portion, patients received oral SHR3680 at a starting daily dose of 40 mg, which was subsequently escalated to 80 mg, 160 mg, 240 mg, 360 mg, and 480 mg per day. In phase 2 dose-expansion portion, patients were randomized to receive daily dose of 80 mg, 160 mg, or 240 mg of SHR3680. The primary endpoint in phase 1 was safety and tolerability and in phase 2 was the proportion of patients with a prostate-specific antigen (PSA) response (≥ 50% decrease of PSA level) at week 12. RESULTS: A total of 197 eligible patients were enrolled and received SHR3680 treatment, including 18 patients in phase 1 and 179 patients in phase 2. No dose-limiting toxicities were reported and the maximum tolerated dose was not reached. Treatment-related adverse events (TRAEs) occurred in 116 (58.9%) patients, with the most common one being proteinuria (13.7%). TRAEs of grade ≥ 3 occurred in only 23 (11.7%) patients, and no treatment-related deaths occurred. Antitumor activities were evident at all doses, including PSA response at week 12 in 134 (68.0%; 95% CI, 61.0-74.5) patients, stabilized bone disease at week 12 in 174 (88.3%; 95% CI, 87.2-95.5) patients, and responses in soft tissue lesions in 21 (34.4%, 95% CI, 22.7-47.7) of 61 patients. CONCLUSION: SHR3680 was well tolerated and safe, with promising anti-tumor activity across all doses tested in patients with metastatic CRPC. The dose of 240 mg daily was recommended for further phase 3 study. TRIAL REGISTRATION: Clinical trials.gov NCT02691975; registered February 25, 2016.
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Neoplasias de la Próstata Resistentes a la Castración , Antagonistas de Andrógenos/farmacocinética , Antagonistas de Andrógenos/uso terapéutico , Antagonistas de Receptores Androgénicos/uso terapéutico , Humanos , Masculino , Dosis Máxima Tolerada , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/patologíaRESUMEN
Acinetobacter baumannii is a successful pathogen that can acquire various antibiotic resistance in a short time. However, little is known about how it can evolve from an antibiotic sensitive to a resistant phenotype. In this study, we investigated the roles of the type VI secretion system (T6SS) in the acquisition of antibiotic resistance of A. baumannii. T6SS gene cluster was found to be present in 51 of 77 A. baumannii clinical isolates, of which, it was found in 62% (8/13) of the multiple drug resistant (MDR) isolates, 90% (36/40) of the extensively drug-resistant (XDR) isolates and 26% (6/23) of the antibiotic sensitive isolates. There is a close relationship between the antimicrobial resistance and the presence of T6SS. Besides, T6SS + isolates showed lower biofilm formation activity and higher survival ability in the presence of normal human serum than T6SS- isolates. A. baumannii A152 with complete T6SS can outcompete E.coli effectively and can acquire the antibiotic resistance plasmids released by E.coli. In contrast, the T6SS core gene mutant A152Δhcp showed significantly decreased ability to acquire antimicrobial resistance plasmids from the prey bacteria. These results suggest that T6SS mediated bacterial competition plays important roles in the antimicrobial resistance of A. baumannii, which points out a new direction for us to study the antimicrobial resistance of A. baumannii.
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Acinetobacter baumannii , Sistemas de Secreción Tipo VI , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Bacteriana Múltiple/genética , Escherichia coli/genética , Humanos , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Sistemas de Secreción Tipo VI/genéticaRESUMEN
The incidence of multidrug-resistant Acinetobacter baumannii has posed a major challenge for clinical treatment. There is still a significant gap in understanding the mechanism causing multi-drug resistance (MDR). In this study, the genomes of 10 drug sensitive and 10 multi-drug resistant A.baumannii strains isolated from a hospital in China were sequenced and compared. The antibiotic resistance genes, virulence factors were determined and CRIPSR-Cas system along with prophages were detected. The results showed that MDR strains are significantly different from the drug sensitive strains in the CARD entries, patterns of sequences matching up to plasmids, VFDB entries and CRISPR-Cas system. MDR strains contain unique CARD items related to antibiotic resistance which are absent in sensitive strains. Furthermore, sequences from genomes of MDR strains can match up with plasmids from more diversified bacteria genera compared to drug sensitive strains. MDR strains also contain a lower level of CRISPR genes and larger amount of prophages, along with higher levels of spacer sequences. These findings provide new experimental evidences for the study of the antibiotic resistance mechanism of A. baumannii.
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Acinetobacter baumannii , Antibacterianos/farmacología , Resistencia a Múltiples Medicamentos , Farmacorresistencia Bacteriana Múltiple/genética , Genómica , Pruebas de Sensibilidad Microbiana , Plásmidos/genéticaRESUMEN
Invited for the cover of this issue is the group of Yu Wang, Feipeng Wang, and co-workers at Chongqing University. The image depicts how activated single-crystal Ti4 O7 nanosheets loaded with precious metals can be used as highly efficient and stable materials to make fuel-cell electrodes for intermittent renewable energy storage in power grids. Read the full text of the article at 10.1002/chem.202202580.
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The oxygen reduction reaction (ORR) is central to modern energy storage and conversion technologies for grids such as fuel cells and electrolyzers, but challenges remain due to the lack of reliable, economic, and durable electrocatalysts. Here, we develop single-crystal conductive black titanium (Ti4 O7 ) nanosheets (NSs) as a new precious metal carrier based on sacrificial hard templates and ultrasonic-assisted peeling, and deposit Pt clusters on Ti4 O7 NSs induced by wetness impregnation under the irradiation of visible light (VI; 650â nm). Pt/Ti4 O7 NSs provide Ti3+ , Pt2+ , and Pt0+ continuous active sites for the ORR multielectron process, achieving synergy among them. The assistance of visible light not only makes a more uniform and smaller distribution of Pt nanoclusters, but also strengthens the charge transfer, thereby constructing a strong metal-support interaction interface. VI-Pt/Ti4 O7 NSs show superior initial oxidation potential and a mass activity of 1.61â A mg-1 Pt at a E1/2 =0.91â V, which is nine times higher than that of commercial Pt/C. This work provides an effective strategy for achieving high-value applications of titanium sub-oxides and further explores the enhanced interface in metals Tin O2n-1 by light radiation.
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Chlorophyll a fluorescence induction kinetics (CFI) is an important tool that reflects the photosynthetic function of leaves, but it remains unclear whether it is affected by leaf structure. Therefore, in this study, the leaf structure and CFI curves of sunflower and sorghum seedlings were analyzed. Results revealed that there was a significant difference between the structures of palisade and spongy tissues in sunflower leaves. Their CFI curves, measured on both the adaxial and abaxial sides, also differed significantly. However, the differences in the leaf structures and CFI curves between both sides of sorghum leaves were not significant. Further analysis revealed that the differences in the CFI curves between the adaxial and abaxial sides of sunflower leaves almost disappeared due to reduced incident light scattering and refraction in the leaf tissues; more importantly, changes in the CFI curves of the abaxial side were greater than the adaxial side. Compared to leaves grown under full sunlight, weak light led to decreased differences in the CFI curves between the adaxial and abaxial sides of sunflower leaves; of these, changes in the CFI curves and palisade tissue structure on the adaxial side were more obvious than on the abaxial side. Therefore, it appears that large differences in sunflower leaf structures may affect the shape of CFI curves. These findings lay a foundation for enhancing our understanding of CFI from a new perspective.
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Helianthus , Clorofila A/análisis , Hojas de la Planta/química , Fotosíntesis , Fluorescencia , Clorofila/análisisRESUMEN
A leaf structure with high porosity is beneficial for lateral CO2 diffusion inside the leaves. However, the leaf structure of maize is compact, and it has long been considered that lateral CO2 diffusion is restricted. Moreover, lateral CO2 diffusion is closely related to CO2 pressure differences (ΔCO2). Therefore, we speculated that enlarging the ΔCO2 between the adjacent regions inside maize leaves may result in lateral diffusion when the diffusion resistance is kept constant. Thus, the leaf structure and gas exchange of maize (C4), cotton (C3), and other species were explored. The results showed that maize and sorghum leaves had a lower mesophyll porosity than cotton and cucumber leaves. Similar to cotton, the local photosynthetic induction resulted in an increase in the ΔCO2 between the local illuminated and the adjacent unilluminated regions, which significantly reduced the respiration rate of the adjacent unilluminated region. Further analysis showed that when the adjacent region in the maize leaves was maintained under a steady high light, the photosynthesis induction in the local regions not only gradually reduced the ΔCO2 between them but also progressively increased the steady photosynthetic rate in the adjacent region. Under field conditions, the ΔCO2, respiration, and photosynthetic rate of the adjacent region were also markedly changed by fluctuating light in local regions in the maize leaves. Consequently, we proposed that enlarging the ΔCO2 between the adjacent regions inside the maize leaves results in the lateral CO2 diffusion and supports photosynthesis in adjacent regions to a certain extent under fluctuating light.
Asunto(s)
Dióxido de Carbono , Zea mays , Dióxido de Carbono/farmacología , Luz , Fotosíntesis , Hojas de la Planta , DifusiónRESUMEN
Tislelizumab, an anti-programmed death protein-1 (PD-1) monoclonal antibody, was engineered to minimize binding to the FcγR on macrophages to abrogate antibody-dependent phagocytosis, a mechanism of T-cell clearance and potential resistance to anti-PD-1 therapy. This single-arm phase 2 trial (NCT04004221/CTR20170071) assessed the safety, tolerability, and efficacy of tislelizumab in patients with PD-L1-positive urothelial carcinoma who progressed during/following platinum-containing therapy and had no prior PD-(L)1 inhibitor treatment. Patients were considered PD-L1 positive if ≥ 25% of tumor/immune cells expressed PD-L1 when using the VENTANA™ PD-L1 (SP263) assay. The primary endpoint was objective response rate by independent review committee. As of September 16, 2019, 113 patients had a median study follow-up time of 9.4 mo. Most patients (76%) had visceral metastases, including 24% with liver and 23% with bone metastases. Among 104 efficacy-evaluable patients, confirmed objective response rate was 24% (95% confidence interval, 16, 33), including 10 complete and 15 partial responses. Median duration of response was not reached. Among 25 responders, 17/25 (68%) had ongoing responses. Median progression-free survival and overall survival times were 2.1 and 9.8 mo, respectively. The most common treatment-related adverse events were anemia (27%) and pyrexia (19%). Anemia (7%) and hyponatremia (5%) were the only grade 3-4 treatment-related adverse events and occurred in ≥ 5% of patients. Three investigator-assessed deaths were considered to be possibly related to study treatment (hepatic failure, n = 2; respiratory arrest, n = 1). Tislelizumab demonstrated meaningful clinical benefits in patients with previously treated locally advanced or metastatic PD-L1-positive urothelial carcinoma and had a manageable safety profile.