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Exercise confers protection against obesity, type 2 diabetes and other cardiometabolic diseases1-5. However, the molecular and cellular mechanisms that mediate the metabolic benefits of physical activity remain unclear6. Here we show that exercise stimulates the production of N-lactoyl-phenylalanine (Lac-Phe), a blood-borne signalling metabolite that suppresses feeding and obesity. The biosynthesis of Lac-Phe from lactate and phenylalanine occurs in CNDP2+ cells, including macrophages, monocytes and other immune and epithelial cells localized to diverse organs. In diet-induced obese mice, pharmacological-mediated increases in Lac-Phe reduces food intake without affecting movement or energy expenditure. Chronic administration of Lac-Phe decreases adiposity and body weight and improves glucose homeostasis. Conversely, genetic ablation of Lac-Phe biosynthesis in mice increases food intake and obesity following exercise training. Last, large activity-inducible increases in circulating Lac-Phe are also observed in humans and racehorses, establishing this metabolite as a molecular effector associated with physical activity across multiple activity modalities and mammalian species. These data define a conserved exercise-inducible metabolite that controls food intake and influences systemic energy balance.
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Ingestión de Alimentos , Conducta Alimentaria , Obesidad , Fenilalanina , Condicionamiento Físico Animal , Adiposidad/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Tipo 2 , Modelos Animales de Enfermedad , Ingestión de Alimentos/fisiología , Metabolismo Energético , Conducta Alimentaria/fisiología , Glucosa/metabolismo , Ácido Láctico/metabolismo , Ratones , Obesidad/metabolismo , Obesidad/prevención & control , Fenilalanina/administración & dosificación , Fenilalanina/análogos & derivados , Fenilalanina/metabolismo , Fenilalanina/farmacología , Condicionamiento Físico Animal/fisiologíaRESUMEN
The design of temperature-adaptive Zn-air batteries (ZABs) with long life spans and high energy efficiencies is challenging owing to sluggish oxygen reduction reaction (ORR) kinetics and an unstable Zn/electrolyte interface. Herein, a quasi-solid-state ZAB is designed by combining atomically dispersed Fe-N-C catalysts containing pyridinic N vacancies (FeNC-VN) with a polarized organo-hydrogel electrolyte. First-principles calculation predicts that adjacent VN sites effectively enhance the covalency of Fe-Nx moieties and moderately weaken *OH binding energies, significantly boosting the ORR kinetics and stability. In situ Raman spectra reveal the dynamic evolution of *O2- and *OOH on the FeNC-VN cathode in the aqueous ZAB, proving that the 4e- associative mechanism is dominant. Moreover, the ethylene glycol-modulated organo-hydrogel electrolyte forms a zincophilic protective layer on the Zn anode surface and tailors the [Zn(H2O)6]2+ solvation sheath, effectively guiding epitaxial deposition of Zn2+ on the Zn (002) plane and suppressing side reactions. The assembled quasi-solid-state ZAB demonstrates a long life span of over 1076 h at 2 mA cm-2 at -20 °C, outperforming most reported ZABs.
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Highly pathogenic avian influenza H5N6 and H5N1 viruses of clade 2.3.4.4b were simultaneously introduced into South Korea at the end of 2023. An outbreak at a broiler duck farm consisted of concurrent infection by both viruses. Sharing genetic information and international surveillance of such viruses in wild birds and poultry is critical.
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Brotes de Enfermedades , Subtipo H5N1 del Virus de la Influenza A , Gripe Aviar , Filogenia , Gripe Aviar/virología , Gripe Aviar/epidemiología , República de Corea/epidemiología , Animales , Subtipo H5N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Patos/virología , Virus de la Influenza A/genética , Virus de la Influenza A/clasificación , Coinfección/virología , Coinfección/epidemiología , Historia del Siglo XXI , Enfermedades de las Aves de Corral/virología , Enfermedades de las Aves de Corral/epidemiologíaRESUMEN
Catalytic therapy has shown great potential for clinical application. However, conventional catalytic therapies rely on reactive oxygen species (ROS) as "therapeutic drugs," which have limitations in effectively inhibiting tumor recurrence and metastasis. Here, a biomimetic heterojunction catalyst is developed that can actively target orthotopic rectal cancer after oral administration. The heterojunction catalyst is composed of quatrefoil star-shaped BiVO4 (BVO) and ZnIn2S4 (ZIS) nanosheets through an in situ direct growth technique. Poly-norepinephrine and macrophage membrane coatings afford the biomimetic heterojunction catalyst (BVO/ZIS@M), which has high rectal cancer targeting and retention abilities. The coupled optical fiber intervention technology activates the multicenter coordination of five catalytic reactions of heterojunction catalysts, including two reduction reactions (O2â·O2 - and CO2âCO) and three oxidation reactions (H2Oâ·OH, GSHâGSSG, and LAâPA). These catalytic reactions not only induce immunogenic death in tumor cells through the efficient generation of ROS/CO and the consumption of GSH but also specifically lead to the use of lactic acid (LA) as an electron donor to improve catalytic activity and disrupt the LA-mediated immunosuppressive microenvironment, mediating synergistic catalysis and immunotherapy for orthotopic rectal cancer. Therefore, this optical fiber intervention triggered the combination of heterojunction catalytic therapy and immunotherapy, which exhibits prominent antitumor effects.
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BACKGROUND: SETDB1 (SET domain bifurcated-1) is a histone H3-lysine 9 (H3K9)-specific methyltransferase that mediates heterochromatin formation and repression of target genes. Despite the assumed functional link between DNA methylation and SETDB1-mediated H3K9 trimethylations, several studies have shown that SETDB1 operates autonomously of DNA methylation in a region- and cell-specific manner. This study analyzes SETDB1-null HAP1 cells through a linked methylome and transcriptome analysis, intending to explore genes controlled by SETDB1-involved DNA methylation. METHODS AND RESULTS: We investigated SETDB1-mediated regulation of DNA methylation and gene transcription in human HAP1 cells using reduced-representation bisulfite sequencing (RRBS) and RNA sequencing. While two-thirds of differentially methylated CpGs (DMCs) in genic regions were hypomethylated in SETDB1-null cells, we detected a plethora of C2H2-type zinc-finger protein genes (C2H2-ZFP, 223 of 749) among the DMC-associated genes. Most C2H2-ZFPs with DMCs in their promoters were found hypomethylated in SETDB1-KO cells, while other non-ZFP genes with promoter DMCs were not. These C2H2-ZFPs with DMCs in their promoters were significantly upregulated in SETDB1-KO cells. Similarly, C2H2-ZFP genes were upregulated in SETDB1-null 293T cells, suggesting that SETDB1's function in ZFP gene repression is widespread. There are several C2H2-ZFP gene clusters on chromosome 19, which were selectively hypomethylated in SETDB1-KO cells. CONCLUSIONS: SETDB1 collectively and specifically represses a substantial fraction of the C2H2-ZFP gene family. Through the en-bloc silencing of a set of ZFP genes, SETDB1 may help establish a panel of ZFP proteins that are expressed cell-type specifically and thereby can serve as signature proteins for cellular identity.
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Metilación de ADN , N-Metiltransferasa de Histona-Lisina , Dedos de Zinc , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Dedos de Zinc/genética , Metilación de ADN/genética , Regiones Promotoras Genéticas/genética , Regulación hacia Arriba/genética , Desmetilación del ADN , Línea Celular , Islas de CpG/genética , Eliminación de Gen , Histonas/metabolismo , Histonas/genéticaRESUMEN
Ten novel hydrophobic dicationic ionic liquids (DILs) were synthesized and applied for the extraction of heavy metals in aqueous solutions. Their physicochemical properties were measured at ambient temperature, and the leaching behaviors of the as-prepared DILs in water were assessed by TOC analysis. Metal extraction experiments were carried out to evaluate the extraction performances of the DILs. It was found that the extraction rates of up to 0.45 and 0.53 mg·(g·min)-1 were achieved with 100 mg DILs for 5 mL of 5 mg/L Cd2+ and Pb2+ solutions. Besides, the extraction efficiencies of Cd2+ and Pb2+ were respectively up to 95.48% and 98.46%, when the volumes of the simulated wastewater were expanded by a factor of 20 at a constant extraction phase ratio (1000 mg DILs for 50 mL of 5 mg/L Cd2+ or Pb2+ solutions). The reusability of the novel DILs was successfully proved by the back-extraction experiments with 0.5 M HNO3. Finally, taking Cd2+ extraction as an example, the extraction mechanism based on FTIR analysis and quantum chemical calculations showed that both S and O atoms in the anions of DILs had physical and quasi-chemical interactions with Cd2+, which were stronger than the electrostatic attraction.
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Líquidos Iónicos , Metales Pesados , Líquidos Iónicos/química , Cadmio , Agua , Plomo , Metales Pesados/químicaRESUMEN
BACKGROUND: This study aimed to assess the radiological and clinical outcomes of treatment using the ankle dislocation method for posterior malleolar malunion. METHOD: Thirty-one patients with posterior malleolar malunion who underwent treatment using the ankle dislocation method from May 2015 to October 2021 were retrospectively analyzed. Key outcome measures were radiographic parameters (articular step-off, tibiofibular clear space, fibular length, tibial lateral surface angle, and ankle osteoarthritis), clinical scores (American Orthopaedic Foot and Ankle Society ankle-hindfoot scale and Visual Analogue Scale), and patient satisfaction rate. RESULT: Preoperative computed tomography revealed that Bartoní cek types 3 and 4 accounted for 64.5 % (n = 20) of total cases. Most posterior malleolar malunions were accompanied by depressed intercalary fragments (61.2 % [n = 19]). At the final follow-up, radiographic parameters and clinical scores showed significant improvements postoperatively (P < 0.05), with a high patient satisfaction rate of 77.4 %. Subgroup analysis revealed that the posterior malleolar fracture morphology significantly affected postoperative pain, particularly in more complex fractures (P < 0.001). CONCLUSION: The ankle dislocation method effectively exposes the distal tibial articular surface and facilitates the anatomical restoration of joint congruity under direct vision. This approach substantially improves the clinical and imaging outcomes in patients with complex posterior malleolar malunion. LEVELS OF EVIDENCE: Level IV, retrospective case series.
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It is clear that humans can extract statistical information from streams of visual input, yet how our brain processes sequential images into the abstract representation of the mean feature value remains poorly explored. Using multivariate pattern analyses of electroencephalography recorded while human observers viewed 10 sequentially presented Gabors of different orientations to estimate their mean orientation at the end, we investigated sequential averaging mechanism by tracking the quality of individual and mean orientation as a function of sequential position. Critically, we varied the sequential variance of Gabor orientations to understand the neural basis of perceptual mean errors occurring during a sequential averaging task. We found that the mean-orientation representation emerged at specific delays from each sequential stimulus onset and became increasingly accurate as additional Gabors were viewed. Especially in frontocentral electrodes, the neural representation of mean orientation improved more rapidly and to a greater degree in less volatile environments, whereas individual orientation information was encoded precisely regardless of environmental volatility. The computational analysis of behavioral data also showed that perceptual mean errors arise from the cumulative construction of the mean orientation rather than the low-level encoding of individual stimulus orientation. Thus, our findings provide neural mechanisms to differentially accumulate increasingly abstract features from a concrete piece of information across the cortical hierarchy depending on environmental volatility.SIGNIFICANCE STATEMENT The visual system extracts behaviorally relevant summary statistical representation by exploiting statistical regularity of the visual stream over time. However, how the neural representation of the abstract mean feature value develops in a temporally changing environment remains poorly identified. Here, we directly recover the mean orientation information of sequentially delivered Gabor stimuli with different orientations as a function of their positions in time. The mean orientation representation, which is regularly updated, becomes increasingly accurate with increasing sequential position especially in the frontocentral region. Further, perceptual mean errors arise from the cumulative process rather than the low-level stimulus encoding. Overall, our study reveals a role of higher cortical areas in integrating stimulus-specific information into increasingly abstract task-oriented information.
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Encéfalo/fisiología , Percepción Visual/fisiología , Electroencefalografía , Femenino , Humanos , Masculino , Orientación/fisiología , Estimulación LuminosaRESUMEN
Lithium-oxygen batteries have the potential to become the most eminent solution for future energy storage with their theoretical energy density exceeding all existing batteries. However, the insulating and insoluble discharge product (lithium peroxide; Li2O2) impairs practical application. Conventional catalyst designs based on the electronic structure and interfacial charge transfer descriptors have not been able to overcome these limitations due to Li2O2. Herein, we revisit the role of heterogeneous catalysts as substrates to regulate Li2O2 growth and the formation of solid/solid reaction interfaces. We demonstrate that controlled solid/solid interfacial structure design is a critical performance parameter beyond the inherent electronic structure. In particular, the Cu2O substrate in this study induces a homogeneous deposition of Pd atoms, which leads to well-controlled growth of Li2O2 resolving mass and charge transport limits (i.e., the bottleneck of oxygen reduction/evolution reactions), thus improving reversibility, capacity, and durability of the cells by dissipating electrochemical and mechanical stress. We thus verified the essential role of solid/solid interfaces to regulate the nucleation and growth process of Li2O2 in lithium-oxygen batteries.
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Reflection phase microscopy is a valuable tool for acquiring three-dimensional (3D) images of objects due to its capability of optical sectioning. The conventional method of constructing a 3D map is capturing 2D images at each depth with a mechanical scanning finer than the optical sectioning. This not only compromises sample stability but also slows down the acquisition process, imposing limitations on its practical applications. In this study, we utilized a reflection phase microscope to acquire 2D images at depth locations significantly spaced apart, far beyond the range of optical sectioning. By employing a numerical propagation, we successfully filled the information gap between the acquisition layers, and then constructed complete 3D maps of objects with substantially reduced number of axial scans. Our experimental results also demonstrated the effectiveness of this approach in enhancing imaging speed while maintaining the accuracy of the reconstructed 3D structures. This technique has the potential to improve the applicability of reflection phase microscopy in diverse fields such as bioimaging and material science.
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Aggressive pancreatic cancer is typically treated using chemotherapeutics to reduce the tumor pre-operatively and prevent metastasis post-operatively, as well as surgical approaches. In the present study, we synthesized a hydroxyl group-introduced chalcone derivative (1, IC50 = 32.1 µM) and investigated its potential as an anticancer drug candidate by evaluating its apoptosis-promoting effects on BXPC-3 cancer cells. The viability of BXPC-3 cells treated with 1 was measured using the water-soluble tetrazolium 1 reagent. BXPC-3 cells induced by 1 were stained with diverse probes or antibodies, such as ethidium homodimer-1, Hoechst, anti-Ki67, and MitoTracker. Protein expression was measured using an immunoblotting assay, and mRNA expression was determined using real-time polymerase chain reaction. Apoptotic molecular features, such as lipid accumulation and protein degradation, were monitored directly using stimulated Raman scattering microspectroscopy. Through incubation time- and concentration-dependent studies of 1, we found that it significantly reduced the proliferation and increased the number of apoptotic BXPC-3 cells. Compound 1 induced mitochondrial dysfunction, phosphorylation of p38, and caspase 3 cleavage. These results indicate that 1 is a potential therapeutic agent for pancreatic cancer, providing valuable insights into the development of new anticancer drug candidates.
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Chalcona , Chalconas , Neoplasias Pancreáticas , Humanos , Chalconas/farmacología , Neoplasias Pancreáticas/tratamiento farmacológico , Apoptosis , Páncreas , Chalcona/farmacología , Neoplasias PancreáticasRESUMEN
89Zr-iPET has been widely used for preclinical and clinical immunotherapy studies to predict patient stratification or evaluate therapeutic efficacy. In this study, we prepared and evaluated 89Zr-DFO-anti-PD-L1-mAb tracers with varying chelator-to-antibody ratios (CARs), including 89Zr-DFO-anti-PD-L1-mAb_3X (tracer_3X), 89Zr-DFO-anti-PD-L1-mAb_10X (tracer_10X), and 89Zr-DFO-anti-PD-L1-mAb_20X (tracer_20X). The DFO-anti-PD-L1-mAb conjugates with varying CARs were prepared using a random conjugation method and then subjected to quality control. The conjugates were radiolabeled with 89Zr and evaluated in a PD-L1-expressing CT26 tumor-bearing mouse model. Next, iPET imaging, biodistribution, pharmacokinetics, and ex vivo pathological and immunohistochemical examinations were conducted. LC-MS analysis revealed that DFO-anti-PD-L1-mAb conjugates were prepared with CARs ranging from 0.4 to 2.0. Radiochemical purity for all tracer groups was >99% after purification. The specific activity levels of tracer_3X, tracer_10X, and tracer_20X were 2.2 ± 0.6, 8.2 ± 0.6, and 10.5 ± 1.6 µCi/µg, respectively. 89Zr-iPET imaging showed evident tumor uptake in all tracer groups and reached the maximum uptake value at 24 h postinjection (p.i.). Biodistribution data at 168 h p.i. revealed that the tumor-to-liver, tumor-to-muscle, and tumor-to-blood uptake ratios for tracer_3X, tracer_10X, and tracer_20X were 0.46 ± 0.14, 0.58 ± 0.33, and 1.54 ± 0.51; 4.7 ± 1.3, 7.1 ± 3.9, and 14.7 ± 1.1; and 13.1 ± 5.8, 19.4 ± 13.8, and 41.3 ± 10.6, respectively. Significant differences were observed between tracer_3X and tracer_20X in the aforementioned uptake ratios at 168 h p.i. The mean residence time and elimination half-life for tracer_3X, tracer_10X, and tracer_20X were 25.4 ± 4.9, 24.2 ± 6.1, and 25.8 ± 3.3 h and 11.8 ± 0.5, 11.1 ± 0.7, and 11.7 ± 0.6 h, respectively. No statistical differences were found between-tracer in the aforementioned pharmacokinetic parameters. In conclusion, 89Zr-DFO-anti-PD-L1-mAb tracers with a CAR of 1.4-2.0 may be better at imaging PD-L1 expression in tumors than are traditional low-CAR 89Zr-iPET tracers.
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Quelantes , Neoplasias , Humanos , Ratones , Animales , Quelantes/uso terapéutico , Radioisótopos/uso terapéutico , Tomografía de Emisión de Positrones/métodos , Anticuerpos Monoclonales/uso terapéutico , Distribución Tisular , Antígeno B7-H1 , Deferoxamina/uso terapéutico , Neoplasias/tratamiento farmacológico , Circonio/farmacocinética , Línea Celular TumoralRESUMEN
Polydeoxyribonucleotide (PDRN) has the ability to regenerate skin cells and improve the skin barrier and wound healing. This study investigated the possibility of replacing animal-derived PDRN with plant-derived PDRN. To test this, the adventitious roots of Korean ginseng (Panax ginseng C.A. Meyer), which is commonly used to treat various diseases, were suspension-cultivated through tissue culture; subsequently, PDRN was purified using microfluidization, an ultra-high-pressure physical grinding method. The results showed that purified Panax PDRN was effective in healing skin wounds and enhancing the skin barrier. Panax PDRN promoted the proliferation of keratinocytes and fibroblasts by increasing the expression of fibronectin, filaggrin, Ki-67, Bcl-2, inhibin beta A, and Cyclin D1. It also acted as an agonist of the adenosine A2A receptor and induced the phosphorylation of focal adhesion kinase, adenosine triphosphate-dependent tyrosine kinase, and mitogen-activated protein kinase. This activated signal transduction, thereby regenerating skin cells and strengthening the barrier. These results were not only observed in skin cells but also in an artificial skin model (KeraSkinTM). The use of plant-derived PDRN instead of animal-derived PDRN can promote animal welfare and environmental sustainability. Furthermore, Panax PDRN can potentially be a new plant-derived PDRN (PhytoPDRN) that may be utilized in the treatment of various skin diseases.
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Panax , Polidesoxirribonucleótidos , Animales , Polidesoxirribonucleótidos/farmacología , Piel , Cicatrización de Heridas , QueratinocitosRESUMEN
INTRODUCTION: Data from acute ischemic stroke patients throughout 2021 from one district of an archipelago city of China were collected and analyzed retrospectively to determine the management difference due to time lags from onset of symptoms to the arrival at the stroke center (FMCT) of two regions: main island (MI) and outer islets (OIs). METHODS: All patients information from 1 January to 31 December 2021 was retrieved through the electronic medical records system of the only stroke center in MI. After screening and exclusion, each patient's medical record was reviewed by two neurologists separately. Before OI patients were allocated to a group, their residential addresses at onset of the stroke were confirmed by telephone. Comparisons were analyzed between the two regions for gender, age, pre-stroke risk factors and peri-admission management parameters. RESULTS: A total of 326 patients met the inclusion criteria: 300 from the MI group and 26 for the OI group. Intergroup comparisons for gender, age and most of the risk factors showed no significant difference. FMCT were shown to be significantly distinct (p<0.001). Hospitalization expenses also showed significant difference. The odds ratio of the definite treatment IV thrombolysis was 0.131 (OI group to MI group range: 0.017-0.987, p=0.021). CONCLUSION: The diagnosis and treatment of acute ischemic stroke patients from OIs was significantly postponed compared to those from MI. Therefore, new effective and efficient solutions are urgently needed.
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Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/terapia , Estudios Retrospectivos , Accidente Cerebrovascular/terapia , Factores de Riesgo , ChinaRESUMEN
Tumor-associated macrophages (TAMs) play a critical role in the immunosuppressive solid tumor microenvironment (TME), yet in situ engineering of TAMs for enhanced tumor immunotherapy remains a significant challenge in translational immuno-oncology. Here, we report an innovative nanodrug-delivering-drug (STNSP@ELE) strategy that leverages two-dimensional (2D) stanene-based nanosheets (STNSP) and ß-Elemene (ELE), a small-molecule anticancer drug, to overcome TAM-mediated immunosuppression and improve chemo-immunotherapy. Our results demonstrate that both STNSP and ELE are capable of polarizing the tumor-supportive M2-like TAMs into a tumor-suppressive M1-like phenotype, which acts with the ELE chemotherapeutic to boost antitumor responses. In vivo mouse studies demonstrate that STNSP@ELE treatment can reprogram the immunosuppressive TME by significantly increasing the intratumoral ratio of M1/M2-like TAMs, enhancing the population of CD4+ and CD8+ T lymphocytes and mature dendritic cells, and elevating the expression of immunostimulatory cytokines in B16F10 melanomas, thereby promoting a robust antitumor response. Our study not only demonstrates that the STNSP@ELE chemo-immunotherapeutic nanoplatform has immune-modulatory capabilities that can overcome TAM-mediated immunosuppression in solid tumors, but also highlights the promise of this nanodrug-delivering-drug strategy in developing other nano-immunotherapeutics and treating various types of immunosuppressive tumors.
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Melanoma , Nanopartículas , Neoplasias , Ratones , Animales , Macrófagos Asociados a Tumores , Macrófagos/metabolismo , Inmunoterapia/métodos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Melanoma/patología , Nanopartículas/uso terapéutico , Microambiente TumoralRESUMEN
The Jahn-Teller effect (JTE) is one of the most important determinators of how much stress layered cathode materials undergo during charge and discharge; however, many reports have shown that traces of superstructure exist in pristine layered materials and irreversible phase transitions occur even after eliminating the JTE. A careful consideration of the energy of cationic distortion using a Taylor expansion indicated that second-order JTE (pseudo-JTE) is more widespread than the aforementioned JTE because of the various bonding states that occur between bonding and antibonding molecular orbitals in transition-metal octahedra. As a model case, a P2-type Mn-rich cathode (Na3/4MnO2) was investigated in detail. MnO6 octahedra are well known to undergo either elongation or contraction in a specific direction due to JTE. Here, the substitution of Li for Mn (Na3/4(Li1/4Mn3/4)O2) helped to oxidize Mn3+ to Mn4+ suppressing JTE; however, the MnO6 octahedra remained asymmetric with a clear trace of the superstructure. With various advanced analyses, we disclose the pseudo-JTE as a general reason for the asymmetric distortions of the MnO6 octahedra. These distortions lead to the significant electrochemical degradation of Na3/4Li1/4Mn3/4O2. The suppression of the pseudo-JTE modulates phase transition behaviors during Na intercalation/deintercalation and thereby improves all of the electrochemical properties. The insight obtained by coupling a theoretical background for the pseudo-JTE with verified layered cathode material lattice changes implies that many previous approaches can be rationalized by regulating pseudo-JTE. This suggests that the pseudo-JTE should be thought more important than the well-known JTE for layered cathode materials.
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As a result of the long-term battle of bacteria and archaea against invaders such as viruses and genetic mobile elements, they have developed CRISPR-Cas systems for self-defense, which allows them to remove the viral genetic material introduced into host cells via infection. To fight against this bacterial immune system, however, viruses have also evolved to produce multiple anti-CRISPR proteins that can inhibit the bacterial CRISPR-Cas system. In this study, we introduced a tentative inhibitory activity against a type I-C CRISPR-Cas system by determining the crystal structure of AcrIC5 from Pseudomonas delhiensis. Structural analysis revealed that AcrIC5 was composed of noble folds comprising two antiparallel sheets and three helices. Although AcrIC5 did not directly interact with either the type I-C cascade from Neisseria lactamia or the type I-F cascade from Pseudomonas aeruginosa in our analysis, a highly acidic surface feature indicated that AcrIC5 may be DNA mimic Acrs that directly binds to the target DNA binding site in type I-C cascade and inhibits the recruitment of the target DNA to this cascade.
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Proteínas Asociadas a CRISPR , Sistemas CRISPR-Cas , Archaea , Bacterias/genética , Proteínas Asociadas a CRISPR/química , Pseudomonas aeruginosa/metabolismoRESUMEN
The microRNA (miRNA) gene cluster on chromosome 19, C19MC, is the largest primate-specific miRNA gene cluster. The 46 homologous miRNA genes in C19MC are highly expressed in the placenta, but repressed in other tissues by DNA methylation. Here, we found that the SET domain bifurcated 1(SETDB1), a histone H3-lysine 9 (H3K9)-specific methyltransferase 1, transcriptionally controls C19MC miRNA genes in a coordinated manner in human HAP1 cells. SETDB1 knockout (KO) resulted in the overexpression of C19MC miRNA genes, which was accompanied by a reduction of H3K9 trimethylation (H3K9me3) in the cluster. We found that SETDB1 specifically binds to and modifies the upstream promoter locus of C19MC with H3K9me3, suggesting its role as a C19MC repressor. Overexpression of C19MC miRNA genes was not related to DNA methylation because cytosine methylation levels were not altered in the C19MC of SETDB1 KO cells, indicating that SETDB1 KO does not cause DNA demethylation in the C19MC promoter and body regions. In conclusion, our results suggest that SETDB1 binding and H3K9 methylation at the C19MC promoter and body regions are responsible for the coordinated regulation of miRNA genes in the cluster.
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N-Metiltransferasa de Histona-Lisina , Histonas , MicroARNs , Humanos , Metilación de ADN , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Regiones Promotoras GenéticasRESUMEN
Despite advancements in synthetic chemistry, nature remains the primary source of drug discovery, and this never-ending task of finding novel and active drug molecules will continue. Flavonoids have been shown to possess highly significant therapeutic activities such as anti-inflammatory, anti-oxidant, anti-viral, anti-diabetic, anti-cancer, anti-aging, neuroprotective, and cardioprotective, etc., However, it has been found that orally administered flavonoids have a critical absorption disorder and, therefore, have low bioavailability and show fluctuating pharmacokinetic and pharmacodynamic responses. A detailed investigation is required to assess and analyze the variation in the bioavailability of flavonoids due to interactions with the intestinal barrier. This review will emphasize on the bioavailability and the pharmacological applications of flavonoids, key factors affecting their bioavailability, and strategies for enhancing bioavailability, which may lead to deeper understanding of the extent of flavonoids as a treatment and/or prevention for different diseases in clinics.
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Descubrimiento de Drogas , Flavonoides , Administración Oral , Antioxidantes , Disponibilidad Biológica , Flavonoides/farmacología , Preparaciones FarmacéuticasRESUMEN
BACKGROUND: We evaluated the long-term efficacy and surgical outcomes of Ahmed glaucoma valve (AGV) implantation in patients with refractory glaucoma by glaucoma type. METHODS: In total, 135 eyes of 135 patients diagnosed with refractory glaucoma and underwent AGV implantation between 2002 and 2018 were reviewed retrospectively. The best-corrected visual acuity (BCVA), intraocular pressure (IOP), and number of antiglaucoma medications were investigated at baseline and follow-up. The cumulative probability of qualified success according to the glaucoma type was evaluated at 12, 24, 36, and 60 months postoperatively. RESULTS: The mean IOP of all patients was 35.7 ± 11.7 mmHg, which was significantly reduced 12.7 ± 7.0 mmHg at 1 week, 16.2 ± 7.5 mmHg at 2 weeks, 17.6 ± 6.8 mmHg at 1 month, 17.5 ± 6.4 mmHg at 3 months, 16.1 ± 6.0 mmHg at 6 months, 16.7 ± 8.0 mmHg at 12 months, 16.4 ± 6.6 mmHg at 24 months, 15.6 ± 5.0 mmHg at 36 months, and 15.6 ± 5.6 mmHg at 60 months after surgery (p < 0.001, respectively). The mean number of antiglaucoma medications was 3.7 ± 1.3, which significantly decreased to 0.4 ± 0.9 at 1 week, 0.3 ± 0.8 at 2 weeks, 0.7 ± 0.9 at 1 month, 1.1 ± 1.1 at 3 months, 1.4 ± 1.0 at 6 months, 1.5 ± 1.1 at 12 months, 1.6 ± 1.2 at 24 months, 1.7 ± 1.2 at 36 months, and 1.8 ± 1.3 at 60 months after surgery (p < 0.001, respectively). The mean BCVA significantly improved from postoperative 2 weeks. Although 71 (52.6%) eyes had postoperative complications, the cumulative probability of surgical success was 72.6% at 12 months, 66.7% at 24 months, and 63.7% at 36 and 60 months. According to the glaucoma type, the success rate of AGV implantation was more than 50% even after 60 months follow-up, except subgroup of neovascular glaucoma (NVG) due to retinal vein occlusion (RVO). CONCLUSIONS: AGV implantation in patients with refractory glaucoma was, after long-term follow-up, successful overall. Therefore, AGV implantation can be an effective surgical option to reduce the IOP and number of antiglaucoma medications and to improve visual acuity for various glaucoma types.