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1.
Nat Immunol ; 22(2): 154-165, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33398185

RESUMEN

Inflammatory caspase sensing of cytosolic lipopolysaccharide (LPS) triggers pyroptosis and the concurrent release of damage-associated molecular patterns (DAMPs). Collectively, DAMPs are key determinants that shape the aftermath of inflammatory cell death. However, the identity and function of the individual DAMPs released are poorly defined. Our proteomics study revealed that cytosolic LPS sensing triggered the release of galectin-1, a ß-galactoside-binding lectin. Galectin-1 release is a common feature of inflammatory cell death, including necroptosis. In vivo studies using galectin-1-deficient mice, recombinant galectin-1 and galectin-1-neutralizing antibody showed that galectin-1 promotes inflammation and plays a detrimental role in LPS-induced lethality. Mechanistically, galectin-1 inhibition of CD45 (Ptprc) underlies its unfavorable role in endotoxin shock. Finally, we found increased galectin-1 in sera from human patients with sepsis. Overall, we uncovered galectin-1 as a bona fide DAMP released as a consequence of cytosolic LPS sensing, identifying a new outcome of inflammatory cell death.


Asunto(s)
Alarminas/metabolismo , Endotoxemia/inmunología , Galectina 1/metabolismo , Mediadores de Inflamación/metabolismo , Inflamación/inmunología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Macrófagos/metabolismo , Proteínas de Unión a Fosfato/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Alarminas/deficiencia , Alarminas/genética , Animales , Estudios de Casos y Controles , Modelos Animales de Enfermedad , Endotoxemia/inducido químicamente , Endotoxemia/metabolismo , Endotoxemia/patología , Femenino , Galectina 1/sangre , Galectina 1/deficiencia , Galectina 1/genética , Células HeLa , Humanos , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Péptidos y Proteínas de Señalización Intracelular/genética , Antígenos Comunes de Leucocito/metabolismo , Lipopolisacáridos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Necroptosis , Proteínas de Unión a Fosfato/deficiencia , Proteínas de Unión a Fosfato/genética , Células RAW 264.7 , Sepsis/sangre , Sepsis/diagnóstico , Transducción de Señal , Regulación hacia Arriba
2.
Nature ; 616(7957): 590-597, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36991122

RESUMEN

Gasdermins (GSDMs) are pore-forming proteins that play critical roles in host defence through pyroptosis1,2. Among GSDMs, GSDMB is unique owing to its distinct lipid-binding profile and a lack of consensus on its pyroptotic potential3-7. Recently, GSDMB was shown to exhibit direct bactericidal activity through its pore-forming activity4. Shigella, an intracellular, human-adapted enteropathogen, evades this GSDMB-mediated host defence by secreting IpaH7.8, a virulence effector that triggers ubiquitination-dependent proteasomal degradation of GSDMB4. Here, we report the cryogenic electron microscopy structures of human GSDMB in complex with Shigella IpaH7.8 and the GSDMB pore. The structure of the GSDMB-IpaH7.8 complex identifies a motif of three negatively charged residues in GSDMB as the structural determinant recognized by IpaH7.8. Human, but not mouse, GSDMD contains this conserved motif, explaining the species specificity of IpaH7.8. The GSDMB pore structure shows the alternative splicing-regulated interdomain linker in GSDMB as a regulator of GSDMB pore formation. GSDMB isoforms with a canonical interdomain linker exhibit normal pyroptotic activity whereas other isoforms exhibit attenuated or no pyroptotic activity. Overall, this work sheds light on the molecular mechanisms of Shigella IpaH7.8 recognition and targeting of GSDMs and shows a structural determinant in GSDMB critical for its pyroptotic activity.


Asunto(s)
Proteínas Bacterianas , Gasderminas , Proteínas Citotóxicas Formadoras de Poros , Animales , Humanos , Ratones , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/ultraestructura , Sitios de Unión , Secuencia Conservada , Microscopía por Crioelectrón , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Proteínas Citotóxicas Formadoras de Poros/ultraestructura , Dominios Proteicos , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/ultraestructura , Piroptosis , Shigella , Especificidad de la Especie , Gasderminas/química , Gasderminas/metabolismo , Gasderminas/ultraestructura
3.
Proc Natl Acad Sci U S A ; 121(5): e2316212121, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38252842

RESUMEN

Fluoro-substitution solvents have achieved great success in electrolyte engineering for high-energy lithium metal batteries, which, however, is beset by low solvating power, thermal and chemical instability, and possible battery swelling. Instead, we herein introduce cyanogen as the electron-withdrawing group to enhance the oxidative stability of ether solvents, in which cyanogen and ether oxygen form the chelating structure with Li+ not notably undermining the solvating power. Cyano-group strongly bonds with transition metals (TMs) of NCM811 cathode to attenuate the catalytic reactivity of TMs toward bulk electrolytes. Besides, a stable and uniform cathode-electrolyte interphase (CEI) inhibits the violent oxidation decomposition of electrolytes and guarantees the structural integrity of the NCM811 cathode. Also, a N-containing and LiF-rich solid-electrolyte interphase (SEI) in our electrolyte facilitates fast Li+ migration and dense Li deposition. Accordingly, our electrolyte enables a stable cycle of Li metal anode with Coulombic efficiency of 98.4% within 100 cycles. 81.8% capacity of 4.3 V NCM811 cathode remains after 200 cycles. Anode-free pouch cells with a capacity of 125 mAh maintain 76% capacity after 100 cycles, corresponding to an energy density of 397.5 Wh kg-1.

4.
PLoS Biol ; 21(5): e3002103, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37141191

RESUMEN

The gasdermins are a family of pore-forming proteins involved in various cellular processes such as cell death and inflammation. A new study in PLOS Biology explores the evolutionary history of gasdermins across metazoans, highlighting the conservation and divergence of gasdermin E.


Asunto(s)
Anfioxos , Piroptosis , Animales , Piroptosis/fisiología , Anfioxos/metabolismo , Gasderminas , Proteínas de Neoplasias/metabolismo , Mecanismos de Defensa
5.
Plant J ; 113(5): 1080-1094, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36625794

RESUMEN

Seed longevity is an important trait for agriculture and the conservation of genetic resources. ß-1,3-Glucanases were first recognized as pathogenesis-related proteins involved in plant defense, but their roles in seeds are largely unknown. Here, we report a glycosylphosphatidylinositol-anchored ß-1,3-glucanase, BG14, that degrades callose in seed embryos and functions in seed longevity and dormancy in Arabidopsis. The loss of function of BG14 significantly decreased seed longevity, whereas functional reversion (RE) and overexpression (OE) lines reversed and increased the impaired phenotype, respectively. The loss of function of BG14 enhanced callose deposition in the embryos of mature seeds, confirmed by quantitative determination and the decreased callose degrading ability in bg14. The drop-and-see (DANS) assay revealed that the fluorescence signal in bg14 was significantly lower than that observed in the other three genotypes. BG14 is located on the periphery of the cell wall and can completely merge with callose at the plasmodesmata of epidermal cells. BG14 was highly expressed in developing seeds and was induced by aging and abscisic acid (ABA). The loss of function of BG14 led to a variety of phenotypes related to ABA, including reduced seed dormancy and reduced responses to treatment with ABA or pacolblltrazol, whereas OE lines showed the opposite phenotype. The reduced ABA response is because of the decreased level of ABA and the lowered expression of ABA synthesis genes in bg14. Taken together, this study demonstrated that BG14 is a bona fide BG that mediates callose degradation in the plasmodesmata of embryo cells, transcriptionally influences ABA synthesis genes in developing seeds, and positively affects seed longevity and dormancy in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Latencia en las Plantas/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Longevidad , Germinación/genética , Ácido Abscísico/metabolismo , Semillas/metabolismo , Regulación de la Expresión Génica de las Plantas
6.
Anal Chem ; 96(28): 11479-11487, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-38943570

RESUMEN

Accurate orientations and stable conformations of membrane receptor immobilization are particularly imperative for accurate drug screening and ligand-protein affinity analysis. However, there remain challenges associated with (1) traditional recombination, purification, and immobilization of membrane receptors, which are time-consuming and labor-intensive; (2) the orientations on the stationary phase are not easily controlled. Herein, a novel one-step synthesis and oriented-immobilization membrane-receptor affinity chromatography (oSOMAC) method was developed to realize high-throughput and accurate drug screening targeting specific domains of membrane receptors. We employed Strep-tag II as a noncovalent immobilization tag fused into platelet-derived growth factor receptor ß (PDGFRß) through CFPS, and meanwhile, the Strep-Tactin-modified monolithic columns are prepared in batches. The advantages of oSOMAC are as follows: (1) targeted membrane receptors can be expressed independent of living cell within 1-2 h; (2) orientation of membrane receptors can be flexibly controlled and active sites can expose accurately; and (3) targeted membrane receptors can be synthesized, purified, and orientation-immobilized on monolithic columns in one step. Accordingly, three potential PDGFRß intracellular domain targeted ligands: tanshinone IIA (Tan IIA), hydroxytanshinone IIA, and dehydrotanshinone IIA were successfully screened out from Salvia miltiorrhiza extract through oSOMAC. Pharmacological experiments and molecular docking further demonstrated that Tan IIA could attenuate hepatic stellate cells activation by targeting the protein kinase domain of PDGFRß with a KD value of 9.7 µM. Ultimately, the novel oSOMAC method provides an original insight for accurate drug screening and interaction analysis which can be applied in other membrane receptors.


Asunto(s)
Receptor beta de Factor de Crecimiento Derivado de Plaquetas , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Ligandos , Humanos , Cromatografía de Afinidad , Evaluación Preclínica de Medicamentos , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/genética , Oligopéptidos/química
7.
J Immunol ; 209(8): 1574-1585, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-36165184

RESUMEN

Neutrophils are critical for mediating inflammatory responses. Inhibiting neutrophil recruitment is an attractive approach for preventing inflammatory injuries, including myocardial ischemia-reperfusion (I/R) injury, which exacerbates cardiomyocyte death after primary percutaneous coronary intervention in acute myocardial infarction. In this study, we found out that a neutrophil exocytosis inhibitor Nexinhib20 inhibits not only exocytosis but also neutrophil adhesion by limiting ß2 integrin activation. Using a microfluidic chamber, we found that Nexinhib20 inhibited IL-8-induced ß2 integrin-dependent human neutrophil adhesion under flow. Using a dynamic flow cytometry assay, we discovered that Nexinhib20 suppresses intracellular calcium flux and ß2 integrin activation after IL-8 stimulation. Western blots of Ras-related C3 botulinum toxin substrate 1 (Rac-1)-GTP pull-down assays confirmed that Nexinhib20 inhibited Rac-1 activation in leukocytes. An in vitro competition assay showed that Nexinhib20 antagonized the binding of Rac-1 and GTP. Using a mouse model of myocardial I/R injury, Nexinhib20 administration after ischemia and before reperfusion significantly decreased neutrophil recruitment and infarct size. Our results highlight the translational potential of Nexinhib20 as a dual-functional neutrophil inhibitory drug to prevent myocardial I/R injury.


Asunto(s)
Antígenos CD18 , Neutrófilos , Animales , Antígenos CD18/metabolismo , Calcio/metabolismo , Adhesión Celular , Guanosina , Guanosina Trifosfato/metabolismo , Humanos , Interleucina-8/metabolismo , Ratones , Ratones Endogámicos C57BL , Neutrófilos/metabolismo , Polifosfatos , Proteína de Unión al GTP rac1/metabolismo
8.
Macromol Rapid Commun ; 45(7): e2300645, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38227948

RESUMEN

In this work, hyperbranched polycarbonate-poly(ethylene oxide) (PEO)-based solid polymer electrolytes (HBPC-SEs) are successfully synthesized via a straightforward organo-catalyzed "A1"+"B2"-ring-opening polymerization approach. The temperature-dependent ionic conductivity of HBPC-SEs, composed of different polycarbonate linkages and various LiTFSI concentrations, is investigated. The results demonstrate that HBPC-SE with an ether-carbonate alternating structure exhibits superior ionic conductivity, attributed to the solubility of Li salts in the polymer matrix and the mobility of the polymer segments. The HBPC1-SE with 30 wt% LiTFSI presents the highest ionic conductivities of 2.15  × 10-5, 1.78 × 10-4, and 6.07 × 10-4 Scm-1 at 30, 60, and 80 °C, respectively. Compared to traditional PEO-based electrolytes, the incorporation of polycarbonate segments significantly enhances the electrochemical stability window (5 V) and Li+ transference number (0.53) of HBPC-SEs. Furthermore, the LiFePO4/HBPC1-SE-3/Li cell exhibits exceptional rate capability and long-cycling performance, maintaining a discharge capacity of 130 mAh g-1 at 0.5C with a capacity retention of 95% after 300 cycles.


Asunto(s)
Litio , Cemento de Policarboxilato , Polímeros , Electrólitos , Metales , Carbonatos
9.
Angew Chem Int Ed Engl ; 63(5): e202317393, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38062863

RESUMEN

Organic electrode materials have attracted a lot interest in batteries in recent years. However, most of them still suffer from low performance such as low electrode potential, slow reaction kinetics, and short cycle life. In this work, we report a strategy of fabricating donor-acceptor (D-A) conjugated polymers for facilitating the charge transfer and therefore accelerating the reaction kinetics by using the copolymer (p-TTPZ) of dihydrophenazine (PZ) and thianthrene (TT) as a proof-of-concept. The D-A conjugated polymer as p-type cathode could store anions and exhibited high discharge voltages (two plateaus at 3.82 V, 3.16 V respectively), a reversible capacity of 152 mAh g-1 at 0.1 A g-1 , excellent rate performance with a high capacity of 124.2 mAh g-1 at 10 A g-1 (≈50 C) and remarkable cyclability. The performance, especially the rate capability was much higher than that of its counterpart homopolymers without D-A structure. As a result, the p-TTPZ//graphite full cells showed a high output voltage (3.26 V), a discharge specific capacity of 139.1 mAh g-1 at 0.05 A g-1 and excellent rate performance. This work provides a novel strategy for developing high performance organic electrode materials through molecular design and will pave a way towards high energy density organic batteries.

10.
Angew Chem Int Ed Engl ; : e202412173, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39205422

RESUMEN

Aqueous Zn-ion batteries (AZIBs) are promising for the next-generation large-scale energy storage. However, the Zn anode remains facing challenges. Here, we report a cyclodextrin polymer (P-CD) to construct quasi-single ion conductor for coating and protecting Zn anodes. The P-CD coating layer inhibited the corrosion of Zn anode and prevented the side reaction of metal anodes. More important is that the cyclodextrin units enabled the trapping of anions through host-guest interactions and hydrogen bonds, forming a quasi-single ion conductor that elevated the Zn ion transference number (from 0.31 to 0.68), suppressed the formation of space charge regions and hence stabilized the plating/striping of Zn ions. As a result, the Zn//Zn symmetric cells coated with P-CD achieved a 70.6 times improvement in cycle life at high current densities of 10 mA cm-2 with 10 mAh cm-2. Importantly, the Zn//K1.1V3O8 (KVO) full-cells with high mass loading of cathode materials and low N/P ratio of 1.46 reached the capacity retention of 94.5% after 1000 cycles at 10 A g-1; while the cell without coating failed only after 230 cycles. These results provide novel perspective into the control of solid-electrolyte interfaces for stabilizing Zn anode and offer a practical strategy to improve AZIBs.

11.
J Am Chem Soc ; 145(23): 12682-12690, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37204114

RESUMEN

Conjugated coordination polymers (CCPs), which possess long-range planar π-d conjugation, are fascinating for various applications because they inherit the merits of both metal-organic frameworks (MOFs) and conducting polymers. However, only one-dimensional (1D) and two-dimensional (2D) CCPs have been reported so far. The synthesis of three-dimensional (3D) CCPs is challenging and even seems theoretically infeasible because conjugation implies 1D or 2D structure. Besides, the redox activity of the conjugated ligands and the π-d conjugation makes the synthesis of CCPs very complicated, and hence, single crystals of CCPs are rarely achieved. Herein, we reported the first 3D CCP and its single crystals with atomically precise structures. The synthesis process involves complicated in situ dimerization, deprotonation of ligands, oxidation/reduction of both ligands and metal ions, and precise coordination between them. The crystals contain in-plane 1D π-d conjugated chains and close π-π interactions between the adjacent chains that are bridged by another column of stacked chains, thus forming 3D CCP with high conductivity (400 S m-1 at room temperature and 3100 S m-1 at 423 K) and potential applications as cathodes in sodium-ion batteries with high capacity, rate capability, and cyclability.

12.
Chemistry ; 29(70): e202303005, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-37823842

RESUMEN

Environmental issues are becoming more and more prominent, and bio-based polymers are essential to alleviate environmental degradation by replacing traditional polymers. With this context, a new family of functional isosorbide-based polyesters and polyamides with high glass transition temperature are prepared via Passerini-Three component polymerization (P-3CP). To optimize the P-3CP conditions, the influence of the polymerization solvent, temperature, feed ratio on the molar mass of final polymers are investigated. The higher molar mass (up to 10100 g/mol) and yield (>70 %) are achieved under very mild conditions (30 °C, standard atmosphere). Functional side groups, such as alkenyl, alkynyl and methyl ester, were introduced into polymer structure via P-3CP by using functional isocyanides. The obtained polyesters and polyamides are characterized by nuclear magnetic resonance (NMR) and infrared (IR) spectroscopies, differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). All polymers are thermal stable and amorphous with variable glass transition temperatures (Tg ). The obtained polyester has Tg up to 87.5 °C, while the Tg of polyamides (ISPA-2) is detected to be 97.5 °C depending on the amide bonds in the polymer backbone and the benzene ring side groups. The cytotoxicity is investigated by the CCK-8 assay against mBMSC cells to confirm the biological safety. Overall, this novel strategy provides an efficient approach to produce functional isosorbide-based polyesters and polyamides, which are promising prospect for being applied to biodegradable materials.

13.
BMC Med Inform Decis Mak ; 23(1): 13, 2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658545

RESUMEN

BACKGROUND: Visual electrophysiology is an objective visual function examination widely used in clinical work and medical identification that can objectively evaluate visual function and locate lesions according to waveform changes. However, in visual electrophysiological examinations, the flash visual evoked potential (FVEP) varies greatly among individuals, resulting in different waveforms in different normal subjects. Moreover, most of the FVEP wave labelling is performed automatically by a machine, and manually corrected by professional clinical technicians. These labels may have biases due to the individual variations in subjects, incomplete clinical examination data, different professional skills, personal habits and other factors. Through the retrospective study of big data, an artificial intelligence algorithm is used to maintain high generalization abilities in complex situations and improve the accuracy of prescreening. METHODS: A novel multi-input neural network based on convolution and confidence branching (MCAC-Net) for retinitis pigmentosa RP recognition and out-of-distribution detection is proposed. The MCAC-Net with global and local feature extraction is designed for the FVEP signal that has different local and global information, and a confidence branch is added for out-of-distribution sample detection. For the proposed manual features,a new input layer is added. RESULTS: The model is verified by a clinically collected FVEP dataset, and an accuracy of 90.7% is achieved in the classification task and 93.3% in the out-of-distribution detection task. CONCLUSION: We built a deep learning-based FVEP classification algorithm that promises to be an excellent tool for screening RP diseases by using FVEP signals.


Asunto(s)
Aprendizaje Profundo , Potenciales Evocados Visuales , Humanos , Estudios Retrospectivos , Inteligencia Artificial , Examen Neurológico
14.
Laterality ; 28(1): 32-47, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36859828

RESUMEN

The golden snub-nosed monkey (Rhinopithecus roxellana) is a typical arboreal group-living Old World primate. While limb preference has been extensively studied in this species, limb preference consistency has not yet been explored. Here, based on 26 R. roxellana adults, we investigated whether individuals exhibit consistent motor biases in manual- (e.g., unimanual feeding and social grooming) and foot-related (e.g., bipedal locomotion) tasks and whether limb preference consistency is influenced by increased social interactions during social grooming. Results showed no consistency in the direction or strength of limb preference among tasks, except for lateral strength in handedness for unimanual feeding and footedness in the initiation of locomotion. Population-level foot preference was only found among right-handers. Marked lateral bias was found in unimanual feeding, indicating that it may be a sensitive behavioural measure for assessing manual preference, especially for provisioned populations. This study not only improves our understanding of the relationship between hand and foot preference in R. roxellana but also reveals potential differential hemispheric regulation of limb preference and the influence of increased social interaction on handedness consistency.


Asunto(s)
Presbytini , Animales , Aseo Animal , Lateralidad Funcional , Locomoción
15.
Angew Chem Int Ed Engl ; 62(27): e202302539, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-36988031

RESUMEN

Redox organic electrode materials (OEMs) have attracted extensive attention for batteries due to the possibility to be designed with high performance. However, the practical application of OEMs requires rigor criteria such as low cost, recyclability, scalability and high performance etc. and hence seems still far away. Here, we demonstrate an OEM for high performance aqueous organic batteries. Quantification of the charge storage confirmed the storage of protons with fast reaction kinetics, thereby enabling the high performance at high mass loading. As a result, the laminated pouch cells delivered Ampere-hour-scale capacity with excellent cycling performance. Benefited from the small molecular nature and the stable both charged and discharged states, the electrodes can be recycled at any states of charge with high yields (more than 90 %). This work provides a substantial step in the practical applications of OEMs for the future sustainable batteries.

16.
Macromol Rapid Commun ; 43(18): e2200198, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35445475

RESUMEN

The electrochemical performance of rechargeable Mg batteries (RMBs) is primarily determined by the cathodes. However, the strong interaction between highly polarized Mg2+ and the host lattice is a big challenge for inorganic cathode materials. While endowed with weak interaction with Mg2+ , organic polymers are capable of fast reaction kinetics. Besides, with the advantages of light weight, abundance, low cost, and recyclability, polymers are deemed as ideal cathode materials for RMBs. Although polymer cathodes have remarkably progressed in recent years, there are still significant challenges to overcome before reaching practical application. In this perspective, the challenges faced by polymer cathodes are critically focused, followed by the retrospection of efforts devoted to design polymers. Some feasible strategies are proposed to explore new structures and chemistries for the practical application of polymer cathodes in RMBs.

17.
Cell Mol Life Sci ; 78(1): 373-384, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32318758

RESUMEN

Faithful chromosome segregation during mitosis requires the correct assembly of kinetochore on the centromere. CENP-A is a variant of histone H3, which specializes the centromere region on chromatin and mediates the kinetochore assembly. The Mis18 complex plays a critical role in initiating the centromere loading of the newly-synthesized CENP-A. However, it remains unclear how Mis18 complex (spMis18, spMis16 and spMis19) is located to the centromere to license the recruitment of Cnp1CENP-A in Schizosaccharomyces pombe. We found that spMis18 directly binds to nucleosomal DNA through its extreme C-terminus and interacts with H2A-H2B dimer via the acidic region on the surface of its Yippee-like domain. Live-cell imaging confirmed that mutation of the acidic region and deletion of the extreme C-terminus significantly impairs the localization of spMis18 and Cnp1 to the centromere and delays chromosome segregation during mitosis. Our findings illustrate that the interaction of spMis18 with histone H2A-H2B and DNA plays important roles in the recruitment of spMis18 and Cnp1 to the centromere in fission yeast.


Asunto(s)
Proteínas Portadoras/metabolismo , ADN/metabolismo , Histonas/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/metabolismo , Proteínas Portadoras/química , Proteínas Portadoras/genética , Centrómero/metabolismo , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Segregación Cromosómica , Cristalografía por Rayos X , ADN/química , Dimerización , Histonas/genética , Microscopía Fluorescente , Mitosis , Simulación de Dinámica Molecular , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Mutagénesis , Unión Proteica , Dominios Proteicos , Estructura Terciaria de Proteína , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/química , Proteínas de Schizosaccharomyces pombe/genética , Imagen de Lapso de Tiempo
18.
Bull Entomol Res ; 112(1): 110-118, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34384510

RESUMEN

In recent decades, the oriental armyworm, Mythimna separata (Walker), has caused severe damage to staple grains in China. However, little is known about when M. separata begin their first migration and the role of males in reproduction and migration. Here, the migratory benefits and reproductive costs of flight frequency were examined in adults under laboratory conditions. We found that flying males had a positive effect on ovarian and reproductive development in females who flew for 1-2 nights by comparing two treatment groups (flying and nonflying male groups). Moreover, flying males decreased the flight capacity and flight propensity of females. In contrast, flight for more than two nights by males significantly inhibited ovarian and reproductive development in adult females. Compared with the controls (0 night), male flight for 1-2 nights significantly shortened the preoviposition period but significantly increased ovarian and reproductive development in females. However, male flight for more than three nights significantly inhibited female reproduction and flight capacity. These results indicate that M. separata begin their first migration within 2 days after emergence and fly for two nights. Prolonged flight times can result in significant reproductive costs. Females initiated their first migration earlier than males due to a stronger flight capacity. These observed findings will be useful for forecasting and monitoring population dynamics to prevent outbreaks of M. separata and reduce crop losses.


Asunto(s)
Mariposas Nocturnas , Oviposición , Animales , China , Femenino , Masculino , Dinámica Poblacional , Reproducción
19.
BMC Med Inform Decis Mak ; 22(1): 27, 2022 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-35101003

RESUMEN

BACKGROUND: Early prediction of noninvasive ventilation failure is of great significance for critically ill ICU patients to escalate or change treatment. Because clinically collected data are highly time-series correlated and have imbalanced classes, it is difficult to accurately predict the efficacy of noninvasive ventilation for severe patients. This paper aims to precisely predict the failure probability of noninvasive ventilation before or in the early stage (1-2 h) of using it on patients and to explain the correlation of the predicted results. METHODS: In this paper, we proposed a SMSN model (stacking and modified SMOTE algorithm of prediction of noninvasive ventilation failure). In the feature generation stage, we used an autoencoder algorithm based on long short-term memory (LSTM) to automatically extract time series features. In the modelling stage, we adopted a modified SMOTE algorithm to address imbalanced classes, and three classifiers (logistic regression, random forests, and Catboost) were combined with the stacking ensemble algorithm to achieve high prediction accuracy. RESULTS: Data from 2495 patients were used to train the SMSN model. Among them, 80% of 2495 patients (1996 patients) were randomly selected as the training set, and 20% of these patients (499 patients) were chosen as the testing set. The F1 of the proposed SMSN model was 79.4%, and the accuracy was 88.2%. Compared with the traditional logistic regression algorithm, the F1 and accuracy were improved by 4.7% and 1.3%, respectively. CONCLUSIONS: Through SHAP analysis, oxygenation index, pH and H1FIO2 collected after 1 h of noninvasive ventilation were the most relevant features affecting the prediction.


Asunto(s)
Ventilación no Invasiva , Algoritmos , Enfermedad Crítica , Humanos , Modelos Logísticos
20.
BMC Med Inform Decis Mak ; 22(1): 59, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-35246122

RESUMEN

BACKGROUND: Venous thromboembolism (VTE) risk assessment in surgical patients is important for the appropriate diagnosis and treatment of patients. The commonly used Caprini model is limited by its inadequate ability to discriminate between risk stratums on the surgical population in southwest China and lengthy risk factors. The purpose of this study was to establish an improved VTE risk assessment model that is accurate and simple. METHODS: This study is based on the clinical data from 81,505 surgical patients hospitalized in the Southwest Hospital of China between January 1, 2019 and June 18, 2021. Among the population, 559 patients developed VTE. An improved VTE risk assessment model, SW-model, was established through Logistic Regression, with comparisons to both Caprini and Random Forest. RESULTS: The SW-model incorporated eight risk factors. The area under the curve (AUC) of SW-model (0.807 [0.758, 0.853], 0.804 [0.765, 0.840]), are significantly superior (p = 0.001 and p = 0.044) to those of the Caprini (0.705 [0.652, 0.757], 0.758 [0.719, 0795]) on two test sets, but inferior (p < 0.001 and p = 0.002) to Random Forest (0.854 [0.814, 0.890], 0.839 [0.806, 0.868]). In decision curve analysis, within threshold range from 0.015 to 0.04, the DCA curves of the SW-model are superior to Caprini and two default strategies. CONCLUSIONS: The SW-model demonstrated a higher discriminative capability to distinguish VTE positive in surgical patients compared with the Caprini model. Compared to Random Forest, Logistic Regression based SW-model provided interpretability which is essential in guarantee the procedure of risk assessment transparent to clinicians.


Asunto(s)
Tromboembolia Venosa , Hospitalización , Humanos , Estudios Retrospectivos , Medición de Riesgo/métodos , Factores de Riesgo , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología
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