The catalytic triad of rice NARROW LEAF1 involves H234.

NARROW LEAF1 (NAL1) exerts a multifaceted influence on leaf morphology and crop yield. Recent crystal study proposed that histidine 233 (H233) is part of the catalytic triad. Here we report that unlike suggested previously, H234 instead of H233 is a component of the catalytic triad alongside residues D291 and S385 in NAL1. Remarkably, residue 233 unexpectedly plays a pivotal role in regulating NAL1's proteolytic activity. These findings establish a strong foundation for utilizing NAL1 in breeding programs aimed at improving crop yield.

Endoplasmic reticulum stress-related protein GRP78 and CHOP levels in synovial fluid correlate with disease progression of primary knee osteoarthritis: A cross-sectional study.

BACKGROUND: Endoplasmic reticulum (ER) stress has been shown to play an important role in osteoarthritis (OA). OBJECTIVE: This study was aimed at assessing the relationship of endoplasmic reticulum (ER) stress-related glucose-regulated protein 78 (GRP78) and CCAAT/enhancer-binding protein homologous protein (CHOP) concentrations in the serum/synovial fluid (SF) with disease severity of primary knee osteoarthritis (pkOA). METHODS: Patients with pkOA together with healthy individuals were consecutively recruited from our hospital. The levels of GRP78 and CHOP in serum / SF were detected using enzyme-linked immunosorbent assay. The levels of IL-6 and MMP-3 were also examined. Radiographic progression of pkOA was evaluated based on Kellgren-Lawrence (K-L) grades. Receiver Operating Characteristic (ROC) curves were used to assess the diagnostic value of GRP78/CHOP levels with regard to K-L grades. The assessment of clinical severity was conducted using the visual analogue scale (VAS), Oxford knee score (OKS), and Lequesne algofunctional index (LAI). RESULTS: A total of 140 pkOA patients and 140 healthy individuals were included. Serum GRP78 and CHOP levels in pkOA patients were not significantly different from those in healthy individuals. The SF GRP78 and CHOP levels in healthy controls were not detected due to ethical reasons. Compared to those with K-L grade 2 and 3, the pkOA patients with K-L grade 4 had higher GRP78 and CHOP levels in the SF with statistical significance. In addition, the pkOA patients with K-L grade 3 exhibited drastically upregulated GRP78 and CHOP concentrations in the SF compared to those with K-L grade 2. Positive correlations of GRP78 and CHOP levels with K-L grades, IL-6, and MMP-3 levels in the SF were observed. ROC curve analysis indicated that both GRP78 and CHOP levels may act as decent indicators with regard to OA. GRP78 and CHOP concentrations in the SF were positively correlated with VAS/LAI score and negatively associated with OKS score. CONCLUSION: The study indicated that GRP78 and CHOP levels in the SF but not the serum were positively correlated with disease severity of pkOA.

Structural insights into the N-terminal APHB domain of HrpA: mediating canonical and i-motif recognition.

RNA helicases function as versatile enzymes primarily responsible for remodeling RNA secondary structures and organizing ribonucleoprotein complexes. In our study, we conducted a systematic analysis of the helicase-related activities of Escherichia coli HrpA and presented the structures of both its apo form and its complex bound with both conventional and non-canonical DNAs. Our findings reveal that HrpA exhibits NTP hydrolysis activity and binds to ssDNA and ssRNA in distinct sequence-dependent manners. While the helicase core plays an essential role in unwinding RNA/RNA and RNA/DNA duplexes, the N-terminal extension in HrpA, consisting of three helices referred to as the APHB domain, is crucial for ssDNA binding and RNA/DNA duplex unwinding. Importantly, the APHB domain is implicated in binding to non-canonical DNA structures such as G-quadruplex and i-motif, and this report presents the first solved i-motif-helicase complex. This research not only provides comprehensive insights into the multifaceted roles of HrpA as an RNA helicase but also establishes a foundation for further investigations into the recognition and functional implications of i-motif DNA structures in various biological processes.

Stimulation of ATP Hydrolysis by ssDNA Provides the Necessary Mechanochemical Energy for G4 Unfolding.

The G-quadruplex (G4) is a distinct geometric and electrophysical structure compared to classical double-stranded DNA, and its stability can impede essential cellular processes such as replication, transcription, and translation. This study focuses on the BsPif1 helicase, revealing its ability to bind independently to both single-stranded DNA (ssDNA) and G4 structures. The unfolding activity of BsPif1 on G4 relies on the presence of a single tail chain, and the covalent continuity between the single tail chain and the G4's main chain is necessary for efficient G4 unwinding. This suggests that ATP hydrolysis-driven ssDNA translocation exerts a pull force on G4 unwinding. Molecular dynamics simulations identified a specific region within BsPif1 that contains five crucial amino acid sites responsible for G4 binding and unwinding. A "molecular wire stripper" model is proposed to explain BsPif1's mechanism of G4 unwinding. These findings provide a new theoretical foundation for further exploration of the G4 development mechanism in Pif1 family helicases.

Epstein-Barr virus-associated poorly differentiated nasopharyngeal adenocarcinoma: a case report and literature review.

Primary Epstein-Barr virus (EBV)-associated poorly differentiated nasopharyngeal adenocarcinoma (NAC) is an extremely rare tumor. In this study, we report a case of EBV-associated poorly differentiated NAC in a 35-year-old man who presented with a clogging sensation in the right ear for 1 month. The first biopsy of the nasopharynx was suggestive of nonkeratinizing carcinoma with weak positivity for CK5/6 and p63. Based on magnetic resonance imaging of the nasopharynx and neck, chest computed tomography, abdominal ultrasound, and whole-body bone scan, the patient was diagnosed with T3N2M0 disease. After the patient received neoadjuvant chemotherapy, concurrent chemoradiotherapy, and adjuvant chemotherapy, partial remission was observed. However, reassessment after 7 months of treatment revealed tumor enlargement. Transnasal endoscopic resection was performed to remove the nasopharyngeal tumor. The postoperative immunostaining results were as follows: CK5/6 (-), p63 (-), MOC31 (+), and Ber-EP4 (+). Meanwhile, EBV-encoded RNA in situ hybridization was positive. A final diagnosis of EBV-associated poorly differentiated NAC was made. Then, the patient received chemotherapy and irradiation but died several months later because of disease progression. Our patient presented with highly malignant EBV-associated poorly differentiated NAC insensitive to chemoradiotherapy with a short survival time of 27 months.

Self-Supporting Co/CeO2 Heterostructures for Ampere-Level Current Density Alkaline Water Electrolysis.

Remodeling the active surface through fabricating heterostructures can substantially enhance alkaline water electrolysis driven by renewable electrical energy. However, there are still great challenges in the synthesis of highly reactive and robust heterostructures to achieve both ampere-level current density hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we report a new Co/CeO2 heterojunction self-supported electrode for sustainable overall water splitting. The self-supporting Co/CeO2 heterostructures required only low overpotentials of 31.9 ± 2.2, 253.3 ± 2.7, and 316.7 ± 3 mV for HER and 214.1 ± 1.4, 362.3 ± 1.9, and 400.3 ± 3.7 mV for OER at 0.01, 0.5, and 1.0 A·cm-2, respectively, being one of the best Co-based bifunctional electrodes. Electrolyzer constructed from this electrode acting as an anode and cathode merely required cell voltages of 1.92 ± 0.02 V at 1.0 A·cm-2 for overall water splitting. Multiple characterization techniques combined with density functional theory calculations disclosed the different active sites on the anode and cathode, and the charge redistributions on the heterointerfaces that can optimize the adsorption of H and oxygen-containing intermediates, respectively. This study presents the tremendous prospective of self-supporting heterostructures for effective and economical overall water splitting.

Molecule-Enhanced Electrocatalysis of Sustainable Oxygen Evolution Using Organoselenium Functionalized Metal-Organic Nanosheets.

Remolding the reactivity of metal active sites is critical to facilitate renewable electricity-powered water electrolysis. Doping heteroatoms, such as Se, into a metal crystal lattice has been considered an effective approach, yet usually suffers from loss of functional heteroatoms during harsh electrocatalytic conditions, thus leading to the gradual inactivation of the catalysts. Here, we report a new heteroatom-containing molecule-enhanced strategy toward sustainable oxygen evolution improvement. An organoselenium ligand, bis(3,5-dimethyl-1H-pyrazol-4-yl)selenide containing robust C-Se-C covalent bonds equipped in the precatalyst of ultrathin metal-organic nanosheets Co-SeMON, is revealed to significantly enhance the catalytic mass activity of the cobalt site by 25 times, as well as extend the catalyst operation time in alkaline conditions by 1 or 2 orders of magnitude compared with these reported metal selenides. A combination of various in situ/ex situ spectroscopic techniques, ab initio molecular dynamics, and density functional theory calculations unveiled the organoselenium intensified mechanism, in which the nonclassical bonding of Se to O-containing intermediates endows adsorption-energy regulation beyond the conventional scaling relationship. Our results showcase the great potential of molecule-enhanced catalysts for highly efficient and economical water oxidation.

Structural mechanism underpinning Thermus oshimai Pif1-mediated G-quadruplex unfolding.

G-quadruplexes (G4s) are unusual stable DNA structures that cause genomic instability. To overcome the potential barriers formed by G4s, cells have evolved different families of proteins that unfold G4s. Pif1 is a DNA helicase from superfamily 1 (SF1) conserved from bacteria to humans with high G4-unwinding activity. Here, we present the first X-ray crystal structure of the Thermus oshimai Pif1 (ToPif1) complexed with a G4. Our structure reveals that ToPif1 recognizes the entire native G4 via a cluster of amino acids at domains 1B/2B which constitute a G4-Recognizing Surface (GRS). The overall structure of the G4 maintains its three-layered propeller-type G4 topology, without significant reorganization of G-tetrads upon protein binding. The three G-tetrads in G4 are recognized by GRS residues mainly through electrostatic, ionic interactions, and hydrogen bonds formed between the GRS residues and the ribose-phosphate backbone. Compared with previously solved structures of SF2 helicases in complex with G4, our structure reveals how helicases from distinct superfamilies adopt different strategies for recognizing and unfolding G4s.

Small extracellular vesicles from mesenchymal stem cells: A potential Weapon for chronic non-healing wound treatment.

Chronic non-healing wounds have posed a severe threat to patients mentally and physically. Behavior dysregulation of remaining cells at wound sites is recognized as the chief culprit to destroy healing process and hinders wound healing. Therefore, regulating and restoring normal cellular behavior is the core of chronic non-healing wound treatment. In recent years, the therapy with mesenchymal stem cells (MSCs) has become a promising option for chronic wound healing and the efficacy has increasingly been attributed to their exocrine functions. Small extracellular vesicles derived from MSCs (MSC-sEVs) are reported to benefit almost all stages of wound healing by regulating the cellular behavior to participate in the process of inflammatory response, angiogenesis, re-epithelization, and scarless healing. Here, we describe the characteristics of MSC-sEVs and discuss their therapeutic potential in chronic wound treatment. Additionally, we also provide an overview of the application avenues of MSC-sEVs in wound treatment. Finally, we summarize strategies for large-scale production and engineering of MSC-sEVs. This review may possibly provide meaningful guidance for chronic wound treatment with MSC-sEVs.

An Efficient Strategy for Reinforcing Flexible Ceramic Membranes.

Herein, we present a facile reinforcement method for the large-scale fabrication of highly flexible, mechanically stable, temperature-resistant ceramic lightweight membranes based on the cross-linked assembly of zirconia-silica (ZrO2-SiO2) nanofibrous and montmorillonite (MMT) nanosheets through electrospinning and a subsequent calcination process. The resulting MMT@ZrO2-SiO2 membranes exhibit high flexibility with a bending rigidity of 0.2 cN mm-1, robust mechanical performance with a tensile strength of up to 1.83 MPa, robust fire resistance, and temperature-invariant mechanical stability from -196 to 1000 °C. The thermal superinsulation with a thermal conductivity as low as 0.026 W m-1 K-1 and the improved mechanical strength can be attributed to the cross-linked interfacial interaction between the ZrO2-SiO2 nanofibers and the MMT nanosheets. Additionally, a firefighter uniform with MMT@ZrO2-SiO2 membranes inside features a superior thermal protective property up to the A2 level (combined flame and radiant exposure) and an excellent fire resistance of up to 1000 °C, which is ideal for next-generation firefighter uniform manufacturing.

Effect of suspension training on neuromuscular function, postural control, and knee kinematics in anterior cruciate ligament reconstruction patients.

BACKGROUND: Suspension training (SET) is a method of neuromuscular training that enables the body to carry out active training under unstable support through a suspension therapy system. However, there have been few reports in the literature on the application of SET to anterior cruciate ligament reconstruction (ACLR) patients. It is not clear what aspects of the patient's function are improved after SET. AIM: To investigate the effect of SET on the neuromuscular function, postural control, and knee kinematics of patients after ACLR surgery. METHODS: Forty participants were randomized to an SET group or a control group. The SET group subjects participated in a SET protocol over 6 wk. The control group subjects participated in a traditional training protocol over 6 wk. Isokinetic muscle strength of the quadriceps and hamstrings, static and dynamic posture stability test, and relative translation of the injured knee were assessed before and after training. RESULTS: The relative peak torque of the quadriceps and hamstrings in both groups increased significantly (P < 0.001), and the SET group increased by a higher percentage than those in the control group (quadriceps: P = 0.004; hamstrings: P = 0.011). After training, both groups showed significant improvements in static and dynamic posture stability (P < 0.01), and the SET group had a greater change than the control group (P < 0.05). No significant improvement on the relative translation of the injured knee was observed after training in either group (P > 0.05). CONCLUSION: Our findings show that SET promotes great responses in quadriceps and hamstring muscle strength and balance function in ACLR patients.

Multifunctional Textiles/Metal-Organic Frameworks Composites for Efficient Ultraviolet Radiation Blocking and Noise Reduction.

Ultraviolet radiation (UVR) and noise are the ubiquitous environmental hazards with considerable detrimental effects on the physiological and psychological health of humans. Exploiting efficient protective materials that can be extensively used in daily life for simultaneous anti-UVR and noise mitigation will be of crucial importance, but it is still a significant challenge in materials design. Herein, we developed a series of protective textiles for efficient anti-UVR and noise reduction via MOFs nanocrystal-modified cotton textiles. The formation of MOFs@cotton textiles was confirmed by using electron microscopy, X-ray diffraction, infrared spectroscopy, and X-ray photoelectron spectroscopy. The fabricated MOFs@cotton textiles exhibited substantial improvement in the UVR blocking and acoustic absorption properties compared to blank cotton textiles. Therefore, this work provides a good strategy for designing and preparing multifunctional protective textiles.

Dynamics of Staphylococcus aureus Cas9 in DNA target Association and Dissociation.

Staphylococcus aureus Cas9 (SaCas9) is an RNA-guided endonuclease that targets complementary DNA adjacent to a protospacer adjacent motif (PAM) for cleavage. Its small size facilitates in vivo delivery for genome editing in various organisms. Herein, using single-molecule and ensemble approaches, we systemically study the mechanism of SaCas9 underlying its interplay with DNA. We find that the DNA binding and cleavage of SaCas9 require complementarities of 6- and 18-bp of PAM-proximal DNA with guide RNA, respectively. These activities are mediated by two steady interactions among the ternary complex, one of which is located approximately 6 bp from the PAM and beyond the apparent footprint of SaCas9 on DNA. Notably, the other interaction within the protospacer is significantly strong and thus poses DNA-bound SaCas9 a persistent block to DNA-tracking motors. Intriguingly, after cleavage, SaCas9 autonomously releases the PAM-distal DNA while retaining binding to the PAM. This partial DNA release immediately abolishes its strong interaction with the protospacer DNA and consequently promotes its subsequent dissociation from the PAM. Overall, these data provide a dynamic understanding of SaCas9 and instruct its effective applications.

[Characteristics of Phosphorus Adsorption in Aqueous Solution By Ca/Mg-Loaded Biogas Residue Biochar].

In this study, we synthesized Ca/Mg biochar sorbents (CMZZs) by pyrolysis of biogas residue (ZZs) impregnated with calcium chloride and magnesium chloride and investigated their potential to adsorb P from water. The results showed that the content of calcium and magnesium in the modified biochar was 1.3 and 15.4 times, respectively, what they were before the modification. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) patterns showed that the type of chemical functional groups on the surface of biochar had not changed, but several new peaks appeared, indicating that Mg (OH)2 and MgO might be present on the surface of the CMZZs. The biochar equilibrium data were well described by the Freundlich model, and the adsorption reached equilibrium after 100 min. The adsorption kinetics followed a pseudo-second-order model, and the maximum adsorption capacity of the CMZZs was 76.92 mg·g-1 when the pH was 9 and the temperature 303 K. The results revealed that a soaking method can effectively load Ca2+ and Mg2+ onto the surface of ZZ, and CMZZs offer a promising adsorbent for P removal with a high adsorption capacity for P from wastewater.

Bacterial degradation of anthraquinone dyes.

Anthraquinone dyes, which contain anthraquinone chromophore groups, are the second largest class of dyes after azo dyes and are used extensively in textile industries. The majority of these dyes are resistant to degradation because of their complex and stable structures; consequently, a large number of anthraquinone dyes find their way into the environment causing serious pollution. At present, the microbiological approach to treating printing and dyeing wastewater is considered to be an economical and feasible method, and reports regarding the bacterial degradation of anthraquinone dyes are increasing. This paper reviews the classification and structures of anthraquinone dyes, summarizes the types of degradative bacteria, and explores the possible mechanisms and influencing factors of bacterial anthraquinone dye degradation. Present research progress and existing problems are further discussed. Finally, future research directions and key points are presented.

Association analysis of polymorphisms of G protein-coupled receptor 54 gene exons with reproductive traits in Jiaxing Black sows.

OBJECTIVE: The aim of this study was to detect single nucleotide polymorphisms (SNP) of G protein-coupled receptor 54 (GPR54) gene and explore association of this candidate gene with reproductive traits in Jiaxing Black sows. METHODS: Six pairs of primers of the gene were designed to amplify all exons thus sequences of which were detected by means of direct sequencing and then SNP loci were scanned. The effects of SNPs on total number of piglets born (TNB), number of piglets born alive (NBA), number of still born piglets (NSB), and litter weight at birth (LWB) of Jiaxing Black sows were analyzed. RESULTS: Three SNP loci, including T3739C, C3878T and T6789C, were identified via comparison of sequencing and two genotypes (AB, BB) at each SNP site were observed. T3739C resulted in the change of amino acid (Leu→Pro) in corresponding protein, and C3878T resulted in synonymous mutation (Ile→Ile). Statistical results demonstrated that allele B was the preponderant allele at the three SNP loci and Genotype BB was the preponderant genotype. Meanwhile, Chi-Square test of these three SNPs indicated that all mutation sites fitted in Hardy-Weinberg equilibrium (p>0.05). For GPR54-T3739C locus, Jiaxing Black sows with genotype BB had 1.23 TNB and 1.28 NBA (p<0.01) that were more than those with genotype AB, respectively. Jiaxing Black sows that had the first two parities with genotype BB had additional 2.23 TNB, 2.27 NBA (p<0.01), and 1.94 LWB (p<0.05) compared to those with genotype AB, respectively. However, for other two loci, no significant difference was found between TNB, NBA, NSB, and LWB, and different genotypes of Jiaxing Black sows. CONCLUSION: In conclusion, the polymorphisms of GPR54-T3739C locus were significantly associated to TNB, NBA, and LWB and could be used as a potential genetic marker to improve reproductive function of Jiaxing black sows.

Evaluation of the four breeds in synthetic line of Jiaxing Black Pigs and Berkshire for meat quality traits, carcass characteristics, and flavor substances.

To investigate breed characteristics and the effect of hybridization of Jiaxing Black Pig (JBP) with Western breeds, the carcass and meat quality traits and flavor substances such as inosinic acids (IMP), intramuscular fat (IMF) in longissimus muscle (LM) from five breeds including JBP, Berkshire, Berkshire × JBP (BJBP), Duroc × Berkshire × JBP (DBJBP), Duroc × Landrace × JBP (DLJBP) were compared in this study. It was found that water holding capacity (WHC) of LM in JBP was significantly higher than that in the other strains (p < 0.01). Dressing out percentage and lean percentage of JBP were both significantly lower than those in the others (p < 0.01) in connection with their lighter carcass weight and higher subcutaneous fat percentage (p < 0.01). Heterosis was realized in DJBP, DBJBP, and DLJBP since their carcass weight, lean percentage, and loin eye muscle area (LEMA) were markedly higher when compared to JBP, whereas lower than those in Berkshire. Among the breeds, the content of IMF and IMP in the LM of JBP were the highest. These traits were also palpably improved in the crossbreds, especially for DBJBP, of which pork was considered outstanding for containing the most abundant essential amino acids (EAA) and total amino acids (TAA).

Attenuated levels of ghrelin in synovial fluid is related to the disease severity of ankle post-traumatic osteoarthritis.

Post-traumatic osteoarthritis (PTOA) of ankle joints results in pain and reduced joint function. Ghrelin, a 28-amino-acid polypeptide, has been previously identified as the first cognate natural ligand that binds to the growth hormone secretagogue receptor. In the present study, ghrelin has been validated to exert cartilage-protective and anti-inflammatory effects. The current study was aimed at investigating the potential role of the levels of serum and synovial fluid (SF) ghrelin on the severity of disease in patients suffering from ankle PTOA. Ninety-seven patients with ankle osteoarthritis who received an arthroscopical examination and debridement or replacement of the ankle joint were included in the study cohort. Meanwhile, 95 healthy individuals (whose age and sex were matched) who received periodic body checkups were enrolled as healthy controls. Enzyme-linked immunosorbent assay (ELISA) was used to analyze the ghrelin levels in serum and SF. SF was also probed for cartilage degradation enzyme matrix metalloproteinases-3 (MMP-3) and tumor necrosis factor alpha (TNF-α), which is a known pro-inflammatory cytokine. The clinical evaluation was carried out using the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot rating scale and visual analogue scale (VAS). The radiographic severity was evaluated using the modified Kellgren-Lawrence (K-L) grading system. We scored for the modified Mankin's score to depict histopathological changes due to cartilage lesions. The diagnostic relevance of the ghrelin concentrations in the prediction of the radiographic grading (in comparison with MMP-3 and TNF-α) was evaluated by calculating the area under the curve of the receiver operating characteristic (ROC) curve. The serum abundance of ghrelin was not significantly altered between ankle PTOA patients and healthy controls. SF ghrelin was negatively correlated with radiographic progression determined by modified ankle K-L grades. In addition SF ghrelin concentrations were negatively related to VAS scores, and positively associated with AOFAS ankle-hindfoot rating. Moreover, SF ghrelin was inversely proportional to the expressions of MMP-3 and TNF-α. ROC analysis curve demonstrated that ghrelin serves as a favorable marker for the diagnosis of radiographic severity by modified ankle K-L grade. The ghrelin concentration in SF is negatively proportional to disease progression in patients suffering from ankle PTOA. Local administration of ghrelin may function as a decent adjuvant therapy to delay the progress of ankle PTOA. © 2019 BioFactors, 45(3):463-470, 2019.