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In the quest to enhance Zn–air batteries (ZABs) for operating across a wide spectrum of temperatures, synthesizing robust oxygen electrocatalysts is paramount. Conventional strategies focusing on orbital hybridization of d–d and p‐d aim to moderate the excessive interaction between the d‐band of the transition metal active site and oxygen intermediate, yet often yield suboptimal performance. Herein, an innovative s‐block metal modulation is reported to refine the electronic structure and catalytic behavior of Co─NC catalysts. Employing density functional theory (DFT) calculations, it is revealed that incorporating Mg markedly depresses the d‐band center of Co sites, thereby fine‐tuning the adsorption energy of the oxygen reduction reaction (ORR) intermediate. Consequently, the Mg‐modified Co─NC catalyst (MgCo─NC) unveils remarkable intrinsic ORR activity with a significantly reduced activation energy (Ea) of 10.0 kJ mol−1, outstripping the performance of both Co─NC (17.6 kJ mol−1), benchmark Pt/C (15.9 kJ mol−1), and many recent reports. Moreover, ZABs outfitted with the finely tuned Mg0.1Co0.9─NC realize a formidable power density of 157.0 mW cm−2, paired with an extremely long cycle life of 1700 h, and an exceptionally minimal voltage gap decay rate of 0.006 mV h−1. Further, the Mg0.1Co0.9─NC‐based flexible ZAB presents a mere 2% specific capacity degradation when the temperature fluctuates from 25 to −20 °C, underscoring its robustness and suitability for practical deployment in diverse environmental conditions. [ABSTRACT FROM AUTHOR]

Ferredoxins (Fds) are crucial in various essential plant metabolic processes, including photosynthesis, fermentation and aerobic nitrogen fixation, due to their role in electron transport rate (ETR). However, the full scope of ferredoxin's function across prokaryotes and eukaryotic plants remains less understood. This study investigated the effect of MtFd from Methanothermobacter thermoautotrophicus on rice photosynthetic efficiency. We found that MtFd was localized in the chloroplasts of rice protoplasts. Transgenic analysis showed that MtFd significantly enhanced the photosynthetic capacity compared to the wild‐type plants. This enhancement was evident through increased ETR, NADPH content and net photosynthetic rates, as well as decreased non‐photochemical quenching (NPQ). Despite similar biomass to wild type plants, MtFd transgenic plants exhibited a marked increase in grain size and the 1000‐grian weight. The elevated ETR and surplus free electrons in transgenic plants result in a considerable rise in cellular ROS content, which in turn enhances the enzymatic activity of the antioxidant system. In summary, our findings suggest that introducing the Fd protein from M. thermoautotrophicus into transgenic rice improves photosynthetic efficiency by accelerating ETR, which triggers the cellular oxidative stress response. [ABSTRACT FROM AUTHOR]

Introduction: Neuromyelitis optica spectrum disorders (NMOSD) is a rare inflammatory demyelinating disease of the central nervous system. NMOSD pathogenesis is mainly mediated by antibodies directed against aquaporin4 (AQP4 antibody). Immunoadsorption (IA) could specifically remove pathogenic antibody to alleviate the disease. Until now, prospective studies concerning the efficacy of IA on NMOSD are scarce. This study aims to prospectively evaluate the efficacy and safety of IA in the treatment of NMOSD. Patients and Methods: We included patients with AQP4 antibody‐positive NMOSD who were hospitalized from September 2019 to September 2020, with no significant improvement in symptoms after 1 week of high‐dose intravenous steroid therapy. Tryptophan IA therapy was initiated with five sessions on alternate days. Expanded Disability Status Scale (EDSS), visual acuity, and laboratory values were measured before and after IA, with a follow‐up of 6 months. Spinal magnetic resonance imaging (MRI) characteristics were collected. Related side effects were recorded. Results: Seven patients were enrolled in the present study. After five IA, the patients' EDSS decreased from 5.71 ± 2.04 to 4.64 ± 2.29, P =.006. The visual acuity of the three visually impaired patients was improved. AQP4‐IgG decreased significantly from 80.00 (interquartile range [IQR], 21.00‐80.00) (U/mL) to 9.72 (IQR, 5.21‐55.57) (U/mL) (P =.018). MRI of the spinal cord showed the scope of the myelopathy was narrowed and no significant enhancement was observed on postcontrast T1‐weighted image at 90 days after treatment. Only one patient had transient hypotension. Conclusions: Tryptophan IA therapy effectively and safely improved neurological function and visual acuity, and reduced the AQP4 antibody concentration in patients with NMOSD. [ABSTRACT FROM AUTHOR]

The Markov chain Monte Carlo (MCMC) algorithm has been used for retrieving ice cloud microphysical properties in this paper. The retrieval data include effective radius (re), ice water content (IWC), number density (N0), and distribution width parameter (w). First we examine the algorithm feasibility using simulated W‐band radar reflectivity. The retrievals locate in a solution space around the exact results. Two methods are applied to produce a unique solution with maximum likelihood function, that is, the mean value of all acceptable sets of parameters in the chain and the first convergence sample. The results of the second method have a better performance compared with that of the first method. The algorithm has better performance when one particle size distribution (PSD) parameter is known than that when three PSD parameters are unknown. Then we apply the algorithm for CloudSat Cloud Profiling Radar (CPR) observations. Four habits, including column, plate, bullet rosette and sphere, are considered to analyze the influence on the retrieval accuracy. The averaged deviation of res and IWCs obtained from MCMC algorithm among different habit assumptions has a maximum of about 10% and 5%, respectively. It appears clearly that the MCMC algorithm retrieval for short hexagonal column (HEXS) are the closest to that of the official products (2B‐CWC‐RO), while thick hexagonal plate (HEXF) has the largest bias. Retrieved re, IWC, N0, and w from radar reflectivity are in reasonable agreement with 2B‐CWC‐RO product, which indicate that the MCMC algorithm can produce reliable cloud properties from radar observations. Plain Language Summary: Ice clouds are globally widespread and their microphysical properties play an important role in the radiative balance of Earth, which are still not well understood and poorly represented. Thus, the algorithm that drive the microphysical properties of ice clouds precisely from radar observations is necessary. Here, we address this issue using Markov chain Monte Carlo algorithm for deriving ice cloud microphysical properties. The feasibility of Markov chain Monte Carlo (MCMC) algorithm has been tested using simulated W‐band radar reflectivity and CloudSat Cloud Profiling Radar observations. The retrievals are in reasonable agreement with CloudSat 2B‐CWC‐RO product. The study will be very useful for analyzing the role that ice clouds play in climate. Key Points: The Markov chain Monte Carlo algorithm has been validated with simulated W‐band radar reflectivity and CloudSat Cloud Profiling Radar (CPR) observationsRetrieved ice cloud microphysical properties are in reasonable agreement with CloudSat 2B‐CWC‐RO productThe crystal habit assumption has significant influence on the accuracy of retrievals [ABSTRACT FROM AUTHOR]

The outcome of nucleos(t)ide analogues (NAs) discontinuation and retreatment is still uncertain. We evaluated hepatitis B surface antigen (HBsAg) kinetics after NAs discontinuation and during retreatment due to off‐treatment clinical relapse among non‐cirrhotic HBeAg‐positive CHB patients. Four groups were studied: 129 HBeAg‐positive patients from a prospective cohort who stopped NAs therapy after achieving sustained response (Group A), 39 patients who received retreatment after off‐treatment clinical relapse in the discontinuation group (Group B), 214 patients who maintained treatment after achieving sustained response (Group C) and 291 patients who firstly initiated antiviral treatment (Group D). During a 5‐year follow‐up, the cumulative incidence of HBsAg loss was significantly higher in Group A than Group C (22.3% vs. 1.6%, p <.001). The quantitative HBsAg (qHBsAg) level at enrolment and NAs discontinuation were independently associated with HBsAg loss. Additionally, patients in Group B showed significantly greater HBsAg loss than those in the Groups C and D, with 5‐year cumulative incidences of 9.0%, 1.6% (p =.040) and 0.6% (p <.001), respectively. Moreover, patients in the Group B exhibited better virologic response (100% vs. 98.8%, p <.001) and HBeAg seroconversion (92.6% vs. 69.8%, p <.001) than those in Group D at year 5. Propensity score‐matched analysis also showed the similar trend of HBsAg decline. NAs discontinuation with or without subsequent retreatment resulted in a more profound reduction of HBsAg in non‐cirrhotic HBeAg‐positive patients, suggesting that discontinuation may be a potential cure strategy for those with sustained virological suppression. [ABSTRACT FROM AUTHOR]

Three six‐coordinate DyIII single‐molecule magnets (SMMs) [Dy(OtBu)2(L)4]+ with local D4h symmetry are obtained by optimizing the equatorial ligands. One of the compounds with L=4‐phenylpyridine shows an energy barrier (Ueff) of 2075(11) K, which is the third largest Ueff, and the first Ueff>2000 K for SMMs with axial‐type symmetry so far. Ab initio analysis indicates that the exceptional uniaxial magnetic anisotropy is deeply related to the axially compressed octahedral geometry. This work provides a new insight into the local D4h symmetry for high‐performance SMMs. [ABSTRACT FROM AUTHOR]

A novel magnetically recoverable copper complex catalyst based on Fe3O4 nanoparticles as a magnetic carrier was successfully synthesized. The catalyst was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, and alternating gradient magnetometry (AGM). The Henry reaction catalyzed by this prepared magnetically recoverable copper complex catalyst proceeded in high yield (97 %) and with high conversion (94 %). The prepared catalyst possesses superparamagnetic properties and can be recycled very conveniently using an external magnetic field. The self‐prepared catalyst has excellent catalytic selectivity and good reusability, making this method a clean and energy‐efficient process. [ABSTRACT FROM AUTHOR]

Summary: D1‐cytoplasmic male sterility (CMS) rice is a sporophytic cytoplasmic male‐sterile rice developed from Dongxiang wild rice that exhibits a no‐pollen‐grain phenotype. A mitochondrial chimeric gene (orf182) was detected by mitochondrial genome sequencing and a comparative analysis. Orf182 is composed of three recombinant fragments, the largest of which is homologous to Sorghum bicolor mitochondrial sequences. In addition, orf182 was found only in wild rice species collected from China. Northern blot analysis showed that orf182 transcripts were affected by Rf genes in the isocytoplasmic restorer line DR7. Western blot analysis showed that the ORF182 product was localized in the mitochondria of the CMS line. An expression cassette containing orf182 fused to a mitochondrial transit peptide induced the maintainer line of male sterility, which lacked pollen grains in the anthers. Furthermore, the in vivo expression of orf182 also inhibited the growth of Escherichia coli, with lower respiration rate, excess accumulation of reactive oxygen species and decreased ATP levels. We conclude that the mitochondrial chimeric gene orf182 possesses a unique structure and origin differing from other identified mitochondrial CMS genes, and this gene is connected to non‐pollen type of sporophytic male sterility in D1‐CMS rice. [ABSTRACT FROM AUTHOR]

Uveal melanoma ( UM) is the most common primary intraocular tumour in adults and has a high incidence. Nearly 50% of patients with UM develop metastases after diagnosis. Long noncoding RNAs (lncRNAs) are involved in both oncogenic and tumour suppression pathways. We show that lnc RNA PAUPAR is present at low levels in UM tissues and cell lines and modulates the tumourigenesis of UM in vitro and in vivo. The ectopic expression of PAUPAR in UM cells revealed that PAUPAR acts as a necessary UM suppressor and induces the silencing of HES1 expression, which significantly reduces tumour metastasis. Mechanistically, PAUPAR modulates HES1 expression by inhibiting histone H3K4 methylation. These data support a role of this lnc RNA as a novel therapeutic target in cancer prevention and treatment. [ABSTRACT FROM AUTHOR]

Epithelial-mesenchymal transition ( EMT) is an important mechanism of cancer invasion and metastasis. Although p53 binding protein 1 ( 53 BP1) has been implicated in several biological processes, its function in EMT of human cancers has not yet been reported. Here, we show that 53 BP1 negatively regulated EMT by modulating ZEB1 through targeting micro RNA (miR)-200b and miR-429. Furthermore, 53 BP1 promoted ZEB1-mediated upregulation of E-cadherin and also inhibited the expressions of mesenchymal markers, leading to increased migration and invasion in MDA- MB-231 breast cancer cells. Consistently, in MCF-7 breast cancer cells, low 53 BP1 expression reduced E-cadherin expression, resulting in increased migration and invasion. These effects were reversed by miR-200b and miR-429 inhibition or overexpression. Sections of tumor xenograft model showed increased ZEB1 expression and decreased E-cadherin expression with the downregulation of 53 BP1. In 18 clinical tissue samples, expression of 53 BP1 was positively correlated with miR-200b and mir-429 and negatively correlated with ZEB1. It was also found that 53 BP1 was associated with lymph node metastasis. Taken together, these results suggest that 53 BP1 functioned as a tumor suppressor gene by its novel negative control of EMT through regulating the expression of miR-200b/429 and their target gene ZEB1. [ABSTRACT FROM AUTHOR]

Channels formed by the canonical transient receptor potential (TRPC) subfamily of proteins are Ca [ABSTRACT FROM AUTHOR]

Abstract: Syntaxin and Munc18 are essential for regulated exocytosis in all eukaryotes. It was shown that Munc18 inhibition of neuronal syntaxin 1 can be overcome by CDK5 phosphorylation, indicating that structural change disrupts the syntaxin–Munc18 interaction. Here, we show that this phosphorylation promotes the assembly of Munc18b–syntaxin 3–SNAP25 tripartite complex and membrane fusion machinery SNARE. Using siRNAs to screen for genes required for regulated epithelial secretion, we identified the requirements of CDK5 and Munc18b in cAMP-dependent gastric acid secretion. Biochemical characterization revealed that Munc18b bears a syntaxin 3-selective binding site located at its most C-terminal 53 amino acids. Significantly, the phosphorylation of Thr572 by CDK5 attenuates Munc18b–syntaxin 3 interaction and promotes formation of Munc18b–syntaxin 3–SNAP25 tripartite complex, leading to an assembly of functional Munc18b–syntaxin 3–SNAP25–VAMP2 membrane fusion machinery. Thus, our studies suggest a novel regulatory mechanism in which phosphorylation of Munc18b operates vesicle docking and fusion in regulated exocytosis. [Copyright &y& Elsevier]

Abstract: Ezrin–radixin–moesin protein family provides a regulated link between the cortical actin cytoskeleton and the plasma membrane. Phosphorylation of ezrin has been functionally linked to membrane dynamics and plasticity. Our recent study demonstrated that phosphorylation of the conserved T567 residue of ezrin alters the physiology of gastric parietal cells. However, the molecular mechanism of phosphorylation-induced ezrin activation has remained elusive. Here we use atomic force microscopy (AFM) to probe phosphorylation-mediated activation of ezrin in single molecules. The phospho-mimicking and non-phosphorylatable mutant ezrin proteins were generated and purified to homogeneity. Comparative analyses of two ezrin mutants by AFM demonstrate the unfolding of the N- and C-terminal domains upon the phospho-activation. To measure the physical force underlying the inter-domain contact during mechanical unfolding, we probed the defined region of ezrin using the N-terminal ezrin coated onto the AFM tip. Comparative force measurements indicate that T567 phosphorylation-induced unfolding of ezrin favors the inter-molecular association. Taken together, these results provide molecular illustration of phosphorylation elicited functional activation of ERM proteins and indicate that stimulus-induced protein conformational change can be used as a signaling mechanism orchestrating cellular dynamics. [Copyright &y& Elsevier]

Chromosome segregation in mitosis is orchestrated by the kinetochore and spindle microtubules stemming from two centrosomes. Our recent studies demonstrated the importance of Nek2A in faithful chromosome segregation during mitosis. Here, we report that Nek2A regulates the function of numatrin in mitosis. The biochemical interaction between Nek2A and numatrin in mitotic cells was revealed by a set of reciprocal immunoprecipitation experiments using Nek2A and numatrin antibodies, respectively. The interaction is validated by a pull-down assay using recombinant Nek2A and numatrin proteins. Moreover, our immunofluorescence studies demonstrate that numatrin becomes centrosome-associated as the cell enters into mitosis and depart from the centrosome after sister chromatid separation in anaphase. The co-localization of numatrin and Nek2A to the centrosome suggests their interaction with and involvement in centrosome function. Indeed, elimination of Nek2A kinase by siRNA diminished its association with the centrosome. Furthermore, we show that numatrin is phosphorylated by wild type but not kinase-death Nek2A. Our studies suggest that the Nek2A kinase cascade is essential for the localization of numatrin to the centrosome. [Copyright &y& Elsevier]

Chromosome segregation in mitosis is orchestrated by dynamic interaction between spindle microtubule and the kinetochore. Our recent ultrastructural studies demonstrated a dynamic distribution of TTK, from the kinetochore to the centrosome, as cell enters into anaphase. Here, we show that a centrosomal protein TACC2 is phosphorylated in mitosis by TTK signaling pathway. TACC2 was pulled down by wild type TTK but not kinase death mutant, suggesting the potential phosphorylation-mediated interaction between these two proteins. Our immunofluorescence studies revealed that both TTK and TACC2 are located to the centrosome. Interestingly, expression of kinase death mutant of TTK eliminated the centrosomal localization of TACC2 but not other centrosomal proteins such as γ-tubulin and NuMA, a phenotype seen in TTK-depleted cells. In these centrosomal TACC2-liberated cells, chromosomes were lagging and mis-aligned. In addition, the distance between two centrosomes was markedly reduced, suggesting that centrosomal TACC2 is required for mitotic spindle maintenance. The inter-relationship between TTK and TACC2 established here provides new avenue to study centrosome and spindle dynamics underlying cell divisional control. [Copyright &y& Elsevier]

The growth of all methanogens is limited to a specific temperature range. However, Methanothermobacter thermautotrophicus can be found in a variety of natural and artificial environments, the temperatures of which sometimes even exceed the temperature growth ranges of thermophiles. As a result, the extent to which methane production and survival are affected by temperature remains unclear. To investigate the mechanisms of methanogenesis that Archaea have evolved to cope with drastic temperature shifts, the responses of Methanothermobacter thermautotrophicus to temperature were investigated under a high temperature growth (71°C) and cold shock (4°C) using Isobaric tags for relative and absolute quantitation (iTRAQ). The results showed that methane formation is decreased and that protein folding and degradation are increased in both high- and low-temperature treatments. In addition, proteins predicted to be involved in processing environmental information processing and in cell membrane/wall/envelope biogenesis may play key roles in affecting methane formation and enhancing the response of M. thermautotrophicus to temperature stress. Analysis of the genomic locations of the genes corresponding to these temperature-dependent proteins predicted that 77 of the genes likely to form 32 gene clusters. Here, we assess the response of M. thermautotrophicus to different temperatures and provide a new level of understanding of methane formation and cellular putative adaptive responses., (© 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)