Comparative proteomic discovery of salt stress response in alfalfa roots and overexpression of MsANN2 confers salt tolerance.

Soil salinity constrains growth, development and yield of alfalfa (Medicago sativa L.). To illustrate the molecular mechanisms responsible for salt tolerance, a comparative proteome analysis was explored to characterize protein profiles of alfalfa seedling roots exposed to 100 and 200 mM NaCl for three weeks. There were 52 differentially expressed proteins identified, among which the mRNA expressions of 12 were verified by Real-Time-PCR analysis. The results showed increase in abundance of ascorbate peroxidase, POD, CBS protein and PR-10 in salt-stressed alfalfa, suggesting an effectively antioxidant and defense systems. Alfalfa enhanced protein quality control system to refold or degrade abnormal proteins induced by salt stress through upregulation of unfolded protein response (UPR) marker PDIs and molecular chaperones (eg. HSP70, TCP-1, and GroES) as well as the ubiquitin-proteasome system (UPS) including ubiquitin ligase enzyme (E3) and proteasome subunits. Upregulation of proteins responsible for calcium signal transduction including calmodulin and annexin helped alfalfa adapt to salt stress. Specifically, annexin (MsANN2), a key Ca2+-binding protein, was selected for further characterization. The heterologous of the MsANN2 in Arabidopsis conferred salt tolerance. These results provide detailed information for salt-responsive root proteins and highlight the importance of MsANN2 in adapting to salt stress in alfalfa.

Optimizing Pollen Germination and Subcellular Dynamics in Pollen Tube of Torreya grandis.

Torreya grandis, a dioecious Taxaceae species of significant economic value in southeast China, presents challenges for natural pollination due to asynchronous maturation of its sex organs and low pollen vitality. In order to enhance fertilization success through artificial pollination of T. grandis, this study investigated the optimal conditions for in vitro pollen germination and pollen tube growth of T. grandis. The optimal in vitro growth medium was found to contain 29mM sucrose, 0.8mM H3BO3, 0.72mM CaCl2, and 0.32mM MgSO4, supplemented with 4µM NAA, 2µM GA3, and 5µM 2,4-D at pH=5.6. Under these conditions, we achieved a maximum pollen germination ratio of 69.99 ± 5.17% and a pollen tube length of 34.38 ± 6.04µm after 6 days germination at 28°C. FM4-64 dye and Mitotracker Red staining revealed highly dynamics of vesicles and mitochondria during germination, which were accumulated at the tip of pollen tube and exhibited biphasic movement patterns. The total number, motion rate, and movement velocity of vesicles as well as mitochondria showed an initially increase followed by a gradual decrease pattern. The presence of sucrose in the medium significantly increased the dynamics and metabolic activity of both vesicles and mitochondria, which may relate with higher pollen germination ratio and faster pollen tube growth compared to sucrose-depleted conditions. Thus, these findings shed light on the physiological characteristics of Torreya pollen germination and provide scientific information for improving Torreya fruit yield through artificial pollination.

Prognostic and predictive value of interstitial lung abnormalities and EGFR mutation status in patients with non-small cell lung cancer.

BACKGROUND: To determine the predictive value of interstitial lung abnormalities (ILA) for epidermal growth factor receptor (EGFR) mutation status and assess the prognostic significance of EGFR and ILA in patients with non-small cell lung cancer (NSCLC). METHODS: We reviewed 797 consecutive patients with a histologically proven diagnosis of primary NSCLC from January 2013 to October 2018. Of these, 109 patients with NSCLC were found to have concomitant ILA. Multivariate logistic regression analysis was used to identify the significant clinical and computed tomography (CT) findings in predicting EGFR mutations. Cox proportional hazard models were used to identify significant prognostic factors. RESULTS: EGFR mutations were identified in 22 of 109 tumors (20.2%). Multivariate analysis showed that the models incorporating clinical, tumor CT and ILA CT features yielded areas under the receiver operating characteristic curve (AUC) values of 0.749, 0.838, and 0.849, respectively. When combining the three models, the independent predictive factors for EGFR mutations were non-fibrotic ILA, female sex, and small tumor size, with an AUC value of 0.920 (95% confidence interval[CI]: 0.861-0.978, p < 0.001). In the multivariate Cox model, EGFR mutations (hazard ratio = 0.169, 95% CI = 0.042-0.675, p = 0.012; 692 days vs. 301 days) were independently associated with extended overall survival compared to the wild-type. CONCLUSION: Non-fibrotic ILA independently predicts the presence of EGFR mutations, and the presence of EGFR mutations rather than non-fibrotic ILA serves as an independent good prognostic factor for patients with NSCLC.

Phosphorus availability regulates nitrogen fixation rate through a key diazotrophic assembly: Evidence from a subtropical Moso bamboo forest subjected to nitrogen application.

Biological N fixation (BNF) is an important N input process for terrestrial ecosystems. Long-term N application increases the availability of N, but may also lead to phosphorus (P) deficiency or an imbalance between N and P. Here, we performed a 5-year N application experiment in a subtropical Phyllostachys heterocycla forest in site and a P application experiment in vitro to investigate the effect of N application on the BNF rate and its regulatory factor. The BNF rate, nifH gene, free-living diazotrophic community composition and plant properties were measured. We found that N application suppressed the BNF rate and nifH gene abundance, whereas the BNF rate in soils with added P was significantly higher overall than that in soils without added P. Moreover, we identified a key diazotrophic assembly (Mod#2), primarily comprising Bradyrhizobium, Geobacter, Desulfovibrio, Anaeromyxobacter, and Pseudodesulfovibrio, which explained 77 % of the BNF rate variation. There was a significant positive correlation between the Mod#2 abundance and soil available P, and the random forest results showed that soil available P is the most important factor affecting the Mod#2 abundance. Our findings highlight the importance of soil P availability in regulating the activities of key diazotrophs, and thus increasing P supply may help to promote N accumulation and primary productivity through facilitating the BNF process in forest ecosystems.

The characteristics of chest HRCT and pulmonary function tests in lung-onset primary sjogren's syndrome.

INTRODUCTION: Interstitial lung disease (ILD) can manifest before the diagnosis of primary Sjögren's syndrome (pSS), however, the underlying mechanisms remain unclear. The aim of this study is to investigate the characteristics of lung-onset pSS using chest high-resolution computerized tomography (HRCT) and pulmonary function tests (PFTs). METHODS: The data of 102 patients with pSS-ILD were retrospectively analyzed. The patients were divided into two groups: lung-onset group and the nonlung-onset group. The chest HRCT, PFTs, and clinical and laboratory data were evaluated and compared. RESULTS: Among the 102 patients with pSS-ILD, 59 (57.8%) were lung-onset and 43 (42.2%) were nonlung-onset. Chest HRCT in the lung-onset group showed higher percentage of usual interstitial pneumonia and nonspecific interstitial pneumonia, the difference did not reach statistical significance. The total HRCT score was higher in the lung-onset group, compared with the nonlung-onset group (2 [2, 3], vs. 2 [1, 2], p = .014). Total lung capacity (TLC) (%pred) [(75.4 ± 16.2) versus (82.8 ± 19.4), p = .049] and forced vital capacity (FVC) (%pred) [(82.2 ± 19.9) versus (91.6 ± 28.3), p = .050] were significantly lower in the lung-onset group, compared with the nonlung-onset group. Residual volume (RV)/TLC (%) significantly increased more than 40% in the lung-onset group (p = .015). Restricted ventilation disorder, small airway obstruction and reduced diffusing capacity of the lung for carbon monoxide/alveolar volume (%Pred) were more common in the lung-onset group (p = .038, p = .050, and p = .050, respectively). Correlation analysis showed that HRCT score was positively correlated with the interval between the onset of pulmonary symptoms and the diagnosis of ILD, serum CA125, and serum CEA. TCL (%pred), VC (%pred), FVC (%pred) were negatively correlated with serum CA125. CONCLUSION: Lung-onset is common in pSS patients with more severe lung function impairments. Serum biomarkers, such CA125, CEA, and ALB, were associated with the severity of lung damage.

Ag10Cu16 nanoclusters with triple-ligand protection: total structure and electronic structure analysis.

Illustrating the molecular structure of metal nanoclusters with the protection of multiple ligands is a prerequisite to understand structure-property relationships of nano or bulk materials with hybrid interfaces. Reported herein is the synthesis, total structure and electronic structure analysis of a new Ag/Cu alloy nanocluster with triple-ligand protection. The cluster with the formula of Ag10Cu16(C8H9S)16(PPh3)4(CF3CO2)8 has been attained in one-pot in a simple way. X-ray single crystal analysis displays its unique metal framework and more importantly rich interface structures. The ligands of phosphine, thioate and carboxylic acid are coordinated to the surface of the cluster in distinctive modes. The electronic structure of the cluster has been revealed by density functional theory, showing that it is a 2-electron superatom with jellium configurations of 1S2. In good accordance with the closure of the geometric and electronic structures, the cluster exhibits moderate stability, which makes it a candidate for further application in many fields.

Lipid droplets proteome reveals dynamic changes of lipid droplets protein during embryonic development of Carya cathayensis nuts.

Lipid droplets (LD) is an important intracellular organelle for triacylglycerols (TAGs) storage. A variety of proteins on the surface of LD coordinately control the contents, size, stability and biogenesis of LD. However, the LD proteins in Chinese hickory (Carya cathayensis) nuts, which is rich in oil and composed of unsaturated fatty acids, have not been identified and their roles in LD formation still remain largely unknown. In present study, LD fractions from three developmental stages of Chinese hickory seed were enriched and the LD fraction accumulated proteins were then isolated and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Protein compositions throughout the various developmental phases were calculated using label-free intensity-based absolute quantification (iBAQ) algorithm. The dynamic proportion of high abundance lipid droplets proteins such as oleosins 2 (OLE2), caleosins 1 (CLO1) and steroleosin 5 (HSD5) increased parallelly with the embryo development. For low abundance lipid droplets proteins, seed LD protein 2 (SLDP2), sterol methyltransferase 1 (SMT1) and LD-associated protein 1 (LDAP1) were the predominant proteins. Moreover, 14 low abundance OB proteins such as oil body-associated protein 2 A (OBAP2A) were selected for future investigation that may associate with embryo development. Overall, 62 differentially expressed proteins (DEPs) were determined by label free quantification (LFQ) algorithms and may involve in LD biogenesis. Furthermore, the subcellular localization validation indicated that selected LD proteins were targeted to the lipid droplets, confirming the promising of proteome data. Taken together, this comparative study may shed light on further study to understand the lipid droplets function in the seed, which contains high oil content.

Newly diagnosed non-small cell lung cancer with interstitial lung abnormality: Prevalence, characteristics, and prognosis.

BACKGROUND: Along with the improvement of lung cancer screening implementation, the identification of interstitial lung abnormality (ILA) is increasing. Currently, there is a limited description of the oncogenic status and ILA subtypes among newly diagnosed non-small cell lung cancer (NSCLC) patients with ILA in the Chinese population. This study aimed to investigate the prevalence, characteristics, oncogenic status and factors associated with overall survival (OS) among NSCLC patients with ILA. METHODS: A total of 765 newly diagnosed NSCLC cases at our hospital were reviewed and ILA was diagnosed according to the criteria of the Fleischner Society. The characteristics, clinical pathological features and OS of NSCLC patients with ILA were retrospectively analyzed. RESULTS: Of the 765 patients included in the study, 101 (13.2%) cases experienced ILA at the time of NSCLC diagnosis. Multivariate analysis revealed that ILA was more likely to be detected in NSCLC patients who were age ≥60 (OR 2.404, p = 0.001), male gender (OR 2.476, p = 0.004), and EGFR wild-type (OR 2.035, p = 0.007). Additionally, according to the multivariate Cox model, the presence of ILA in NSCLC patients was significantly associated with a shorter OS period than those without ILA (751 days vs. 445 days, HR 0.6, p = 0.001). Following analysis, it was determined that OS in patients with usual interstitial pneumonia (UIP) was shorter than in those without UIP (HR 1.82, p = 0.037). CONCLUSION: ILA is a common comorbidity among newly diagnosed NSCLC patients. We found that patients with EGFR wild-type NSCLC were more likely to develop ILA. The presence of ILA, especially UIP, was significantly associated with poor NSCLC prognosis.

Pericholecystic varices as the predominant manifestation in cryptogenic portal hypertension: A case report.

BACKGROUND: Portal hypertension has various manifestations, and varices are a common manifestation. Varices can appear in any vein in the body associated with the portal venous system. CASE PRESENTATION: Herein, we report a case of portal hypertension with gallbladder varices as the main manifestation, which was confirmed by abdominal contrast-enhanced CT with three-dimensional reconstruction and color Doppler ultrasonography. The patient had concomitant liver cirrhosis and portal vein thrombosis. Various auxiliary examinations and biochemical indicators of the patient confirmed liver cirrhosis, portal vein thrombosis, and portal hypertension, all of which were mild and did not reach the decompensation stage. CONCLUSION: As illustrated by this case, when there is an embolism in certain parts of the portal system, portal hypertension can appear during the compensatory period and transition into severe varices in the thrombotic part during the de-compensatory period.

Optimization design of the sound absorbing structure of double-layer porous metal material with air layer based on genetic algorithm.

An acoustic absorption structure of a double-layer porous metal material with air layers is proposed. The Johnson-Champoux-Allard (JCA) model combined with the transfer matrix method (TMM) was used to establish the theoretical calculation model of the sound absorption coefficient (SAC). Meanwhile, the SAC between 500 and 6300 Hz were measured with an impedance tube. The errors between the theoretical and experimental values were compared to illustrate the good predictability of the theoretical model within the inverse estimations of the transport properties. The effects of the material placement order, material thickness, and cavity depth on the sound absorption performance from 200 to 5000 Hz were analyzed using the theoretical model. Further, a multi-objective function genetic algorithm was used to optimize the porous material's thickness and SAC to obtain an acoustic structure with a smaller thickness and higher sound absorption. A series of optimal solutions were obtained for acoustic structures with a total thickness of less than 70 mm. When the total thickness of the foam metal was 33.57 mm, the average SAC reached 0.853, which was significantly lower than the total thickness of the previous experiments. The multi-objective function genetic algorithm can provide a reliable solution for the optimal design of most sound-absorbing structures.

Characteristics of Chest HRCT and pulmonary function tests in elderly-onset primary Sjögren syndrome with interstitial lung disease.

To investigate the characteristics of elderly-onset primary Sjögren syndrome (pSS) using chest high-resolution computed tomography and pulmonary function tests (PFTs). The data of 102 patients with pSS with interstitial lung disease were retrospectively analyzed. The chest high-resolution computed tomography, PFTs, and clinical and laboratory data were evaluated based on the age of onset: elderly-onset pSS (EopSS) (≥65 years) versus adult-onset pSS (AopSS) (<65 years). Among the 102 patients with pSS-interstitial lung disease, there were 34 of EopSS and 68 of AopSS. EopSS patients presented a significantly higher incidence of usual interstitial pneumonia (EopSS [38.2%] vs AopSS [11.8%], P = .005) and a significantly lower incidence of nonspecific interstitial pneumonia (EopSS [8.8%] vs AopSS [25%], P = .042). Unlike the AopSS group, the significant decreases in the vital capacity (VC) (the percentage of the predicted value of each parameter [%pred]) and the forced VC (%pred), PFTs showed that VC (%pred) and forced VC (%pred) were >80% in the EopSS group. Forced expiratory volume in 1 second significantly decreased and residual volume significantly increased in the EopSS group (P = .001). The percentage of small airway disease was significantly higher in the EopSS group (P = .021). Diffusing capacity of the lung for carbon monoxide/alveolar volume (%pred) was <80% in both groups with a lower percentage in the AopSS group. Usual interstitial pneumonia is more common in the EopSS group. Although there is no significant difference in ventilation dysfunction between the EopSS and AopSS groups, small airway disease is more common in the EopSS group, while restrictive ventilatory dysfunction is more common in the AopSS group. Therefore, the EopSS group has its own characteristics and it is worth studying and noting.

Multiplex polymerase spiral reaction for simultaneous detection of Salmonella typhimurium and Staphylococcus aureus.

Salmonella typhimurium (S. typhimurium) and Staphylococcus aureus (S. aureus) are common food-borne pahogens that cause food poisoning in humans. In this study, we developed a method for the simultaneous determination of S. typhimurium and S. aureus based on multiplex polymerase spiral reaction (m-PSR) and melting curve analysis. Two pairs of primers were designed specifically to target the conserved invA gene of S. typhimurium and nuc gene of S. aureus, and the nucleic acid amplification reaction was achieved under isothermal conditions in the same reaction tube for 40 min at 61 °C, melting curve analysis of the amplification product was carried out. The distinct mean melting temperature allowed simultaneous differentiation of the two target bacteria in the m-PSR assay. The limit of detection of S. typhimurium and S. aureus that could be detected simultaneously was 4.1 × 10-4 ng genomic DNA and 2 × 101 CFU/mL pure bacterial culture. Based on this method, analysis of artificially contaminated samples showed excellent sensitivity and specificity consistent with those of pure bacterial cultures. This method is rapid, simultaneous and promises to be a useful tool for the detection of food-borne pathogens in the food industry.

Fabrication of Robust Waterborne Superamphiphobic Coatings with Antifouling, Heat Insulation, and Anticorrosion.

Water-based superamphiphobic coatings that are environmentally friendly have attracted tremendous attention recently, but their performances are severely limited by dispersibility and mechanical durability. Herein, a dispersion of poly(tetrafluoroethylene)/SiO2@cetyltrimethoxysilane&sodium silicate-modified aluminum tripolyphosphate (PTFE/SiO2@CTMS&Na2SiO3-ATP) superamphiphobic coatings was formed by mechanical dispersion of poly(tetrafluoroethylene) emulsion (PTFE), modified silica emulsion (SiO2@CTMS), sodium silicate (Na2SiO3), and modified aluminum tripolyphosphate (modified ATP). The four kinds of emulsions were mixed together to effectively solve the dispersity of waterborne superamphiphobic coatings. Robust waterborne superamphiphobic coatings were successfully obtained by one-step spraying and curing at 310 °C for 15 min, showing strong adhesive ability (grade 1 according to the GB/T9286), high hardness (6H), superior antifouling performance, excellent impact resistance, high-temperature resistance (<415 °C), anticorrosion (immersion of strong acid and alkali for 120 h), and heat insulation. Remarkably, the prepared coating surface showed superior wear resistance, which can undergo more than 140 abrasion cycles. Moreover, the composite coating with 35.53 wt % SiO2@CTMS possesses superamphiphobic properties, with contact angles of 160 and 156° toward water and glycerol, respectively. The preparation method of superamphiphobic coatings may be expected to present a strategy for the preparation of multifunctional waterborne superamphiphobic coatings with excellent properties and a simple method.

An atomically precise Ag18Cu8 nanocluster with rich alkynyl-metal coordination structures and unique SbF6- assembling modes.

Elucidating the coordination structures and assembling modes of atomically precise metal nanoclusters (NCs) remains a hot topic as it gives answers to the underlying mechanism of nanomaterials and bulk materials in terms of structure-property relationships. Here we report a novel silver-copper alloy NC featuring rich alkynyl-metal coordination modes and unique SbF6- assembling structures. The NC, with the composition of [Ag18Cu8(dppp)4(tBu-C6H4CC)22](SbF6)4 (dppp = 1,3-bis(diphenylphosphino)-propane), was prepared by a stepwise synthetic approach. Single-crystal X-ray diffraction analysis revealed that such a NC featured a staircase-like Ag18Cu8 kernel, which was protected by hybrid alkynyl and dppp ligands in diverse coordination structures and multiple environments. The structural analysis also revealed the unique function of SbF6- in inducing the assembly of cluster moieties, highlighting the importance of counterions in assembling nanomolecules. The diverse coordination structures of the protective ligands with metal ions and the indispensable roles of counterions in assembling the cluster moieties have also been supported by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS) studies, making it a model system to showcase the uniqueness of atomically precise metal NCs in illustrating the coordination chemistry of nanomaterials and bulk materials at the molecular level.

Amelioration effects of the soybean lecithin-gallic acid complex on iron-overload-induced oxidative stress and liver damage in C57BL/6J mice.

CONTEXT: Gallic acid (GA) and lecithin showed important roles in antioxidant and drug delivery, respectively. A complex synthesized from GA and soybean lecithin (SL-GAC), significantly improved bioavailability of GA and pharmacological activities. However, the antioxidant activity of SL-GAC and its effect on iron-overload-induced liver injury remains unexplored. OBJECTIVE: This study investigates the antioxidant properties of SL-GAC in vitro and in mice, and its remediating effects against liver injury by iron-overloaded. MATERIALS AND METHODS: In vitro, free radical scavenging activity, lipid peroxidation inhibition, and ferric reducing power of SL-GAC were measured by absorbance photometry. In vivo, C57BL/6J mice were randomized into 4 groups: control, iron-overloaded, iron-overloaded + deferoxamine, and iron-overloaded + SL-GAC. Treatments with deferoxamine (150 mg/kg/intraperitioneally) and SL-GAC (200 mg/kg/orally) were given to the desired groups for 12 weeks, daily. Iron levels, oxidative stress, and biochemical parameters were determined by histopathological examination and molecular biological techniques. RESULTS: In vitro, SL-GAC showed DPPH and ABTS free radicals scavenging activity with IC50 values equal to 24.92 and 128.36 µg/mL, respectively. In C57BL/6J mice, SL-GAC significantly reduced the levels of serum iron (22.82%), liver iron (50.29%), aspartate transaminase (25.97%), alanine transaminase (38.07%), gamma glutamyl transferase (42.11%), malondialdehyde (19.82%), total cholesterol (45.96%), triglyceride (34.90%), ferritin light chain (18.51%) and transferrin receptor (27.39%), while up-regulated the levels of superoxide dismutase (24.69%), and glutathione (11.91%). CONCLUSIONS: These findings encourage the use of SL-GAC to treat liver injury induced by iron-overloaded. Further in vivo and in vitro studies are needed to validate its potential in clinical medicine.

An alkynyl-protected Ag13-xCu6+x nanocluster for catalytic hydrogenation.

A novel alkynyl-stabilized silver-copper alloy nanocluster with the composition of [Ag13-xCu6+x(tBuC6H4CC)14(PPh3)6](SbF6)3 was prepared by the (PPh3)2CuBH4-mediated reduction approach. The nanocluster features a centred disordered-octahedral Ag7Cu6 kernel, which is protected by hybrid alkynyl and triphenylphosphine ligands. Structural comparison of this two-electron nanocluster with other alkynyl-capped Ag/Cu ones suggested that the structure of alkynyl ligands played an important role in dictating the structures of the resulting nanoclusters. The title cluster showed high performance in the catalytic hydrogenation of 4-nitrophenol, indicative of the bright future of cluster-based catalysts.

Prediction of the Sound Absorption Coefficient of Three-Layer Aluminum Foam by Hybrid Neural Network Optimization Algorithm.

The combination of multilayer aluminum foam can have high sound absorption coefficients (SAC) at low and medium frequencies, and predicting its absorption coefficient can help the optimal structural design. In this study, a hybrid EO-GRNN model was proposed for predicting the sound absorption coefficient of the three-layer composite structure of the aluminum foam. The generalized regression neural network (GRNN) model was used to predict the sound absorption coefficient of three-layer composite structural aluminum foam due to its outstanding nonlinear problem-handling capability. An equilibrium optimization (EO) algorithm was used to determine the parameters in the neuronal network. The prediction results show that this method has good accuracy and high precision. The calculation result shows that this proposed hybrid model outperforms the single GRNN model, the GRNN model optimized by PSO (PSO-GRNN), and the GRNN model optimized by FOA(FOA-GRNN). The prediction results are expressed in terms of root mean square error (RMSE), absolute error, and relative error, and this method performs well with an average RMSE of only 0.011.

Dual-Role of Cholesterol-25-Hydroxylase in Regulating Hepatitis B Virus Infection and Replication.

Hepatitis B virus (HBV)-related diseases are among the major diseases that affect millions of people worldwide. These diseases are difficult to eradicate and thus pose a serious global health challenge. There is an urgent need to understand the cross talk mechanism between HBV and the host. Cholesterol-25-hydroxylase (CH25H) and its enzymatic product, 25-hydroxycholesterol (25HC), were previously shown to exhibit effective broad-spectrum antiviral activity. However, the role of CH25H in the regulation of HBV infection and replication remains unclear. The present study reported increased expression of CH25H in HBV-infected patients compared to healthy subjects. Importantly, higher expression of CH25H expression was found to be associated with low HBV replication. Additionally, the present study aimed to identify CH25H mutants, which would lack hydroxylase activity but retain antiviral activity toward HBV infection and replication. Interestingly, it was observed that both CH25H and its mutants interacted with HBx protein and inhibited nuclear translocation of HBx. In particular, CH25H interacted with the C-terminal region of HBx, while transmembrane region 3 of CH25H was found to be critical for CH25H-HBx interaction and inhibition of HBV replication. The study results suggested that 25HC promoted HBV infection but not HBV replication. Thus, the results of the present study suggested the involvement of a dual mechanism in CH25H-mediated regulation of HBV replication. The study clearly demonstrated cross talk between HBV and the host through CH25H-HBx axis. IMPORTANCE The enzymatic product of CH25H, 25-hydroxycholesterol (25HC), has been previously shown to play a critical role in the blockage of the cell-virus fusion in response to viral infection. However, our study indicates a dual role of CH25H in regulating HBV. We find the CH25H-mediated inhibition of HBV replication is independent on its enzyme activity and CH25H binds to HBx and inhibits HBx nucleus translocation. We are interested to find out 25HC promotes HBV infection.

Co-ligand triphenylphosphine/alkynyl-stabilized undecagold nanocluster with a capped crown structure.

We report the synthesis and crystal structure of novel co-ligand phosphine/alkynyl protected Au nanoclusters, with composition [Au11(PPh3)8(C[triple bond, length as m-dash]CPh-CF3)2](SbF6) (1). The gold atoms in the cluster as a capped crown structure subtend C 3v symmetry with one deriving from a central icosahedron and 10 peripheral Au atoms, and all alkynides are exclusively σ coordination bonding. The mean core diameter is about 5.1 Å and the overall van der Waals diameter can be estimated to be 20.5 Å. The optical absorbance of 1 in solution reveals characteristic peaks at 384 and 426 nm and a shoulder between 450 and 550 nm.

Three-Dimensional Supramolecular Architectures with MnII Ions Assembled from Hydrogen Bonding Interactions: Crystal Structures and Antiferromagnetic Properties.

Two novel cocrystal MnII compounds were successfully synthesized. The composition of two kinds crystals correspond to [Mn(hfac)2La 2·Mn(hfac)2La(H2O)·Mn(hfac)2(H2O)2] (1) and [Mn(hfac)2Lb 2·Mn(hfac)2(H2O)2·0.5(C6H14)] (2) [La = 1,3-bis(1'-oxyl-3'-oxido-4',4',5',5'-tetramethyl-4,5-dihydro-1H-imidazol-2-y1)benzene; Lb = 1-(1'-oxyl-4',4',5',5'-tetramethylimidazolin-2-yl)-3-(1'-oxyl-3'-oxo-4',4',5',5'-tetramethylimidazolin-2-yl)benzene; hfac = hexafluoroacetylacetonato). Surprisingly, the compounds were not polymeric or clusters but, more interestingly, different ratio biradical-metal coordination compound cocrystals. The extensive intramolecular H-bonds are the cause of formation of the cocrystal structures by assembly in the two manganese(II) derivatives; and another factor is the halogen bonds between CF3 of hfac groups. Furthermore, three-dimensional supramolecular architectures were formed. The magnetic susceptibility of both compounds showed strong antiferromagnetic interactions involving the coordinated radical unit and the metal and lesser contribution from ferromagnetic interactions between the radical units. For compound 1, a good fit was obtained for g Mn = 2.08, g rad = 2.00 (fixed), J 1 = -294.3 cm-1, J 2 = 6.2 cm-1 and J 3 = 10.8 cm-1. A reasonable fit for compound 2 was obtained for g Mn = 2.04, g rad = 2.00 (fixed), J 1' = -273.4 cm-1 and J 2' = 8.6 cm-1.