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We propose a new consistency test for the $\Lambda$CDM cosmology using baryonic acoustic oscillations (BAO) and redshift space distortion (RSD) measurements from galaxy redshift surveys. Specifically, we determine the peak position of $f\sigma_8(z)$ in redshift $z$ offered by a RSD measurement, and compare it to the one predicted by the BAO observables assuming a flat $\Lambda$CDM cosmology. We demonstrate this new test using the simulated data for the DESI galaxy survey, and argue that this test complements those using the background observables alone, and is less subject to systematics in the RSD analysis, compared to traditional methods using values of $f\sigma_8(z)$ directly., Comment: 9 pages, 6 figures; accepted to Research in Astronomy and Astrophysics (RAA)

Protein lysine monomethylation is an important post-translational modification participated in regulating many biological processes. There is growing interest in identifying these methylation events. However, the introduction of one methyl group on lysine residues has negligible effect on changing the physical and chemical properties of proteins or peptides, making enriching and identifying monomethylated lysine (Kme1) proteins or peptides extraordinarily challenging. In this study, we proposed an antibody-free chemical proteomics approach to capture Kme1 peptides from complex protein digest. By exploiting reductive glutaraldehydation, 5-aldehyde-pentanyl modified Kme1 residues and piperidine modified primary amines were generated at the same time. The peptides with aldehyde modified Kme1 residues were then enriched by solid-phase hydrazide chemistry. This chemical proteomics approach was validated by using several synthetic peptides. It was demonstrated that it can enrich and detect Kme1 peptide from peptide mixture containing 5000-fold more bovine serum albumin tryptic digest. Besides, we extended our approach to profile Kme1 using heavy methyl stable isotope labeling by amino acids in cell culture (hmSILAC) labeled Jurkat T cells and Hela cells. Totally, 29 Kme1 sites on 25 proteins were identified with high confidence and 11 Kme1 sites were identified in both two types cells. This is the first antibody-free chemical proteomics approach to enrich Kme1 peptides from complex protein digest, and it provides a potential avenue for the analysis of methylome.

An ultra-long (5 m) open tubular capillary liquid chromatographic column was prepared by incorporating Metal Organic Framework (MOF), zeolitic imidazolate framework-8 (ZIF-8), directly into polymer coating, which was synthesized by the copolymerization of 4-vinylbenzyl chloride and divinylbenzene, on the capillary inner surface. The prepared ZIF-8 incorporate polymeric open tubular capillary column (denoted as ZIF-8-p(VBC/DVB) OTCC) was evaluated with thiourea, alkylbenzenes and polycyclic aromatic hydrocarbons as probe molecules. The results showed that the ultra-long column achieved absolute column efficiency of 130,000 plates for thiourea, and the incorporation of ZIF-8 effectively improved the chromatography performance of the OTCC. Baseline separation of aromatic compounds and position isomers was achieved based on multiple interactions provided by the zeolitic imidazolate framework and polymer, including hydrophobic interaction, π-π stacking interaction and the coordination effect. The RSD values (run-to-run, day-to-day, column-to-column, n = 3) of retention time of phenylenediamine isomers and propylbenzene isomers were less than 0.7%, 1.2% and 4.0% respectively, suggesting excellent repeatability. Finally, the prepared ZIF-8-p(VBC/DVB) OTCC was applied to the separation of hydroxyacetophenone isomers with satisfied results.

Background Infection with Salmonella enterica usually results in diarrhea, fever, and abdominal cramps, but some people become asymptomatic or chronic carrier as a source of infection for others. This study aimed to analyze the difference in serotype, antimicrobial resistance, and genetic profiles between Salmonella strains isolated from patients and those from asymptomatic people in Nantong city, China. Methods A total of 88 Salmonella strains were collected from patients and asymptomatic people from 2017 to 2018. Serotyping, antimicrobial susceptibility testing, and PFGE analysis were performed to analyze the characteristics of these strains. Results Twenty serotypes belonging to 8 serogroups were identified in the 88 Salmonella strains. S. Typhimurium remained to be the predominant serotype in strains from both patients and asymptomatic people. Among the 27 strains from patients, S. Enteritidis and S. Rissen were shown as the other two major serotypes, while S. London, S. Derby, and S. Meleagridis were demonstrated as the other significant serotypes among the 61 strains from asymptomatic people. Antimicrobial resistance testing revealed that 84.1% of strains from both resources were multi-drug resistant. PFGE displayed a highly discriminative ability to differentiate strains belonging to S. Derby, S. Typhimurium, etc., but could not efficiently differentiate serotypes like S. Enteritidis. Conclusions This study’s results demonstrated that S. Typhimurium could cause human infection in both symptomatic and asymptomatic state; S. London, S. Derby, and S. Meleagridis usually cause asymptomatic infection, while S. Enteritidis infection mainly results in human diseases. The high multi-drug resistance rate detected in the antimicrobial resistance and diverse PFGE profiles of these strains implied that the strains were isolated from different sources, and the increased surveillance of Salmonella from both patients and asymptomatic people should be taken to control the disease.

In this work, a dual-functionalized magnetic bimetallic metal-organic framework composite denoted as Fe3O4@SiO2@(Zr–Ti-MOF)10-NH2 was ingeniously designed and fabricated by a facial layer-by-layer assembly technique. The composite not only exhibited strong affinity for phosphopeptide due to the coexistence of Zr–O clusters and Ti–O clusters, but also owned great hydrophilicity for glycopeptides relying on abundant hydrophilic NH2 groups, meeting the demand for simultaneously enrichment and sequential elution of phosphopeptides and glycopeptides. As expected, the synthesized composite showed great selectivity (1:2000 M ratio of β-casein:BSA; 1:50 M ratio of IgG:BSA), good sensitivity (1 fmol μL−1 for both α-casein and IgG), and good capacity (80 mg g−1 for α-casein and 200 mg g−1 for IgG). By using sequential elution strategy, 29 phosphopeptides and 24 glycopeptides from α-casein and IgG digests mixture could be simultaneously enriched and respectively detected through a single-step enrichment and sequential elution method. Furthermore, the composite was successfully applied to the analysis of intricate biological samples. 4 endogenous phosphopeptides and 20 phosphopeptides were trapped from human serum and non-fat milk tryptic digest respectively. From 0.5 mg of tryptic digest of rat brain, 141 N-linked glycopeptides corresponding to 127 glycoproteins and 918 phosphopeptides corresponding to 397 phosphoproteins were enriched simultaneously and identified respectively, proving the Fe3O4@SiO2@(Zr–Ti-MOF)10-NH2 to be a dependable candidate for the simultaneously enrichment of trace phosphopeptides and glycopeptides in intricate biological samples.

Zhao, Gong-Bo, et al., We perform a joint BAO and RSD analysis using the eBOSS DR16 LRG and ELG samples in the redshift range of z [0.6, 1.1], and detect an RSD signal from the cross-power spectrum at a ∼4σ confidence level, i.e., fσ8 = 0.317 ± 0.080 at zeff = 0.77. Based on the chained power spectrum, which is a new development in this work to mitigate the angular systematics, we measure the BAO distances and growth rate simultaneously at two effective redshifts, namely, DM/rd (z = 0.70) = 17.96 ± 0.51, DH/rd (z = 0.70) = 21.22 ± 1.20, fσ8 (z = 0.70) = 0.43 ± 0.05, and DM/rd (z = 0.845) = 18.90 ± 0.78, DH/rd (z = 0.845) = 20.91 ± 2.86, fσ8 (z = 0.845) = 0.30 ± 0.08. Combined with BAO measurements including those from the eBOSS DR16 QSO and Lyman-α sample, our measurement has raised the significance level of a non-zero ωΛ to ∼11σ. The data product of this work is publicly available at https://github.com/icosmology/eBOSS_DR16_LRGxELG and https://www.sdss.org/science/final-bao-and-rsd-measurements/., GBZ is supported by the National Key Basic Research and Development Program of China (No. 2018YFA0404503), and a grant of CAS Interdisciplinary Innovation Team. GBZ, YW, and WBZ are supported by NSFC Grants 11925303, 11720101004, 11673025, and 11890691. YW is also supported by the Nebula Talents Program of NAOC and by the Youth Innovation Promotion Association CAS. EMM has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (grant agreement no. 693024).

The complex 4f and 5d orbits of lanthanide oxide clusters increases the complexity and difficulty in both theoretical and experimental research. Combining the photoelectron imaging spectroscopy and ab initio calculations, the structural and electronic properties of HoO

Four naphthalimide-based compounds (NHA, NHB, NHC and NHD) bearing carbazide or semi-carbazide at different positions were designed and synthesized for the detection of cooper ions. The presence of copper ions caused different spectral changes of the four compounds: the fluorescence of NHA and NHB were enhanced, while that of NHC was quenched, and little spectral changes of NHD were observed. The mechanism studies reveal that: copper ions promoted the hydrolysis of the probe containing semi-carbazide group (NHA), leading to evident fluorescence enhancement with clear red-shift; while it formed complex with the probes bearing carbazide (NHB and NHC), resulting in fluorescence “turn-on” or “turn-off”. The substituted position of carbazide group in naphthalimide affected the fluorescence significantly: strong photoinduced electron transfer occurred as it at 4-position (NHB), whereas the PET process was not easy to happen as the group at imine-N (NHC). Copper ions increased the fluorescence of NHB by blocking the PET process, while it could initiate a d-PET process and quenched the fluorescence of NHC. Fluorescence bio-imaging experiments demonstrate that both NHB and NHC exhibit good cell permeability and can monitor Cu2+ as well as thiols in living cells.

A challenge for shotgun proteomics is the identification of low abundance proteins, which is always hampered owing to the extreme complexity of protein digests and highly dynamic concentration range of proteins. To reduce the complexity of the peptide mixture, we developed a novel method to selectively enrich N-terminal proline peptides via hydrazide chemistry. This method consisted of ortho-phthalaldehyde (OPA) blocking of primary amines in peptides, reductive glutaraldehydation of N-terminal proline and solid phase hydrazide chemistry enrichment of aldehyde-modified N-terminal proline peptide. After enrichment, the number of detected peptides containing N-terminal proline increased from 1304 to 4039 and the ratio of N-terminal proline peptides jumped from 4.4% to 93.7%, showing good enrichment specificity towards N-terminal proline peptides. Besides, the ratio of identified peptides to proteins was decreased from 7.8 (29751/3811) to 1.5 (4347/2821), indicating that sample complexity was drastically reduced through this method. As a result, this novel approach for enriching N-terminal proline peptides is effective in identification of low abundance protein owing to the reduction of sample complexity.

Osteoarthritis (OA) is the most prevalent chronic degenerative disease that affects the health of the elderly. The present study aimed to identify significant genes involved in OA via bioinformatics analysis. A gene expression dataset (GSE104793) was downloaded from the Gene Expression Omnibus. Bioinformatics analysis was then performed in order to identify differentially expressed genes (DEGs) between untreated chondrocytes and chondrocytes cultured with interleukin-1β (IL-1β) for 24 h. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using Metascape. A protein-protein interaction network of DEGs was constructed using the Search Tool for the Retrieval of Interacting Genes. Gene set enrichment analysis (GSEA) was performed using GSEA software. Furthermore, chondrocytes were extracted and treated with IL-1β (10 ng/ml) for 24 h, and reverse-transcription quantitative PCR was used to confirm differential expression of hub genes. Patient samples were also collected to verify the bioinformatic analysis results. Based on the cut-off criteria used for determination of the DEGs, a total of 844 DEGs, including 498 upregulated and 346 downregulated DEGs, were identified. The DEGs were mainly enriched in the GO terms and KEGG pathways 'inflammatory response', 'negative regulation of cell proliferation', 'ossification', 'taxis', 'blood vessel morphogenesis', 'extracellular structure organization', 'mitotic cell cycle process' and 'TNF signaling pathway'. The majority of the PCR results, namely the differential expression of kininogen 2, complement C3, cyclin B1, cell division cycle 20, cyclin A2, 1-phosphatidylinositol 4-kinase, BUB1 mitotic checkpoint serine/threonine kinase, kinesin family member 11, cyclin B2 and BUB1 mitotic checkpoint serine/threonine kinase B were consistent with the bioinformatics results. Collectively, the present observations provided a regulation network of IL-1β-stimulated chondrocytes, which may provide potential targets of OA therapy.

In this study, a new molecularly imprinted material, MIP@UiO-66-NH2, was synthesized with glutathione (GSH) as template and mesoporous metal organic framework (UiO-66-NH2) as matrix. The molecularly imprinted polymer was modified on the surface and into the pores of the UiO-66-NH2 by surface molecular imprinting method with thin polymer layer. Based on high specific surface area (1091.93 m2 g−1) and appropriate pore size (35 nm) of the ordered mesoporous UiO-66-NH2, the adsorption capacity for GSH reached 94.43 mg g−1, and the adsorption equilibrium could be achieved within 30 min. The adsorption isotherm data of MIP@UiO-66-NH2 could be described well by Freundlich model and the kinetic data complied well with pseudo-second-order model. In addition, the MIP@UiO-66-NH2 showed low adsorption capacity to GSH structural analogs (QL-cys = 6.51 mg g−1), suggesting great selectivity for GSH recognition. Finally, the MIP@UiO-66-NH2 was successfully applied for selective separation of GSH from BSA, skim milk and egg white tryptic digest.

Osteocytes sense extracellular mechanical stimuli and transduce them into biochemical signals to regulate bone remodeling. The function is also evidenced in orthodontic tooth movement. But the underlying mechanisms haven't been clarified. Autophagy is an evolutionarily conserved cellular catabolic process which affects cellular secretory capabilities. We hypothesized that mechanical force activated osteocyte autophagy through TFE3-related signaling and further promoted osteocyte-mediated osteoclastogenesis. In the present study, we demonstrated that osteocyte autophagy was activated under mechanical compressive force using murine orthodontic tooth movement model since the number of LC3B-positive osteocytes increased by 3-fold in the compression side. In addition, both in vitro mechanical compression and chemical autophagy agonist increased the secretion of RANKL in osteocytes by 3-fold and 4-fold respectively, which is a crucial cytokine for osteoclastogenesis. Lastly, conditioned medium collected from compressed osteocytes promoted the development of osteoclasts. These results suggest that osteocytes could promote osteoclastogenesis via autophagy-mediated RANKL secretion under mechanical compressive force. Our research might provide evidence for exploring methods to accelerate tooth movement in clinic.

Highly selective and efficient enrichment of trace phosphorylated proteins or peptides from complex biological samples is of profound significance for the discovery of disease biomarkers in biological systems. In this study, a novel immobilized metal affinity chromatography (IMAC) material has been synthesized to improve the enrichment specificity and sensitivity for phosphopeptides by introducing a titanium phosphate moiety on a multilayer polysaccharide (hyaluronate (HA) and chitosan (CS)) coated Fe

Doushen, a traditional Chinese fermented soybean product, may be spiced or spicy depending on whether pepper powder is added. While numerous studies have investigated the microbial communities of other fermented foods, little is known on the fungal diversity of Doushen. Therefore, in this study, we investigated the fungal community and diversity in both spiced and spicy Doushen. Our results revealed that fungal species richness significantly differed between the samples with different flavors. A total of nine phyla and 188 fungal genera were identified, and Ascomycota and Aspergillus were predominant in all samples. Based on linear discriminant analysis, a total of 57 OTUs were significantly different between the two samples. Results of non-metric multidimensional scaling and unweighted pair-group analysis suggested that the presence of pepper powder affects the microbial community in Doushen. Network analysis showed that microbial interactions between fungal communities in Doushen with different flavors were significantly different. The results on the enumeration and identification of fungi were consistent with the composition of the dominant genera in the samples with different flavors. This study provides a theoretical basis for future research on food ecology in Doushen.

Two fluorescent probes were designed by connecting indomethacin to coumarin through different linkers. The introduction of indomethacin quenched the fluorescence of coumarin-based probes with apparent red-shifts in the absorption and emission maxima, probably due to the photoinduced electron transfer (PET) from the indomethacin to the fluorophore and the formation of folding conformation. The addition of human serum albumin (HSA) triggered about 40-fold fluorescence enhancements of ADC-IMC-2 and ADC-IMC-6 with 85 nm blue-shifts. The probe with longer spacer ADC-IMC-6 exhibited ratiometric fluorescent response toward HSA, and that with shorter linker showed “off-on” fluorescence response to HSA. However, insignificant spectral changes of the reference compounds (ADC-6 and ADC-2) initiated by HSA implied that indomethacin played critical role in the identification of HSA. The competitive assays and molecular docking results reveal that the indomethacin in ADC-IMC-6 could tightly combine at drug site I of HSA. Fluorescence bio-imaging experiments show that both probes could distinguish cancer cells from normal cells.

The construction of the great canals of China enjoys a long history. It started from the excavation of canals between adjacent watersheds, and finally formed nowadays national water transport network with the Beijing-Hangzhou Great Canal as the backbone to connect all the major water systems in China. The emergence and development of the great canals of China not only manifests the world-leading achievements in hydraulic science and technology made by ancient China, but also relates to its national historical development, always producing a significant impact on the development of the country.

The lymphatic system plays a crucial role in the maintenance of tissue fluid homeostasis and the immunological response to inflammation. The effects of lymphatic drainage dysfunction on periodontitis have not been well studied. Here we show that lymphatic vessel endothelial receptor 1 (LYVE1)+ /podoplanin (PDPN)+ lymphatic vessels (LVs) are increased in the periodontal tissues, with accumulation close to the alveolar bone surface, in two murine periodontitis models: rheumatoid arthritis (RA)-associated periodontitis and ligature-induced periodontitis. Further, PDPN+ /alpha-smooth muscle actin (αSMA)- lymphatic capillaries are increased, whereas PDPN+ /αSMA+ collecting LVs are decreased significantly in the inflamed periodontal tissues. Both mouse models of periodontitis have delayed lymph flow in periodontal tissues, increased TRAP-positive osteoclasts, and significant alveolar bone loss. Importantly, the local administration of adeno-associated virus for vascular endothelial growth factor C, the major growth factor that promotes lymphangiogenesis, increases the area and number of PDPN+ /αSMA+ collecting LVs, promotes local lymphatic drainage, and reduces alveolar bone loss in both models of periodontitis. Lastly, LYVE1+ /αSMA- lymphatic capillaries are increased, whereas LYVE1+ /αSMA+ collecting LVs are decreased significantly in gingival tissues of patients with chronic periodontitis compared with those of clinically healthy controls. Thus, our findings reveal an important role of local lymphatic drainage in periodontal inflammation-mediated alveolar bone loss. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Herein, new near-infrared (NIR) luminescent ruthenium complexes were prepared for detecting Cu2+ ions. Then, ruthenium complex hybrid nanomaterials (Ru–LPMSNs) were fabricated successfully by imbedding the ruthenium complex into mesoporous silica nanoparticles. Benefiting from the novel large-pore mesoporous structure and good adsorbility of LPMSNs, Ru–LPMSN hybrid materials showed a significantly enhanced fluorescence intensity and stability. NIR fluorescence of Ru–LPMSNs was rapidly quenched by Cu2+ ions. Ru–LPMSNs also showed high Cu2+ ion selectivity and sensitivity as a sensor. The detection limit of Cu2+ ions was 10 nM with a wide linear relationship between the fluorescence intensity of Ru–LPMSNs and the concentration of Cu2+ ions. The mechanism of fluorescence quenching might be that the combination of the ruthenium complex and Cu2+ ions constrained the photoinduced electron-transfer process. Furthermore, Ru–LPMSNs dramatically increased the fluorescence signals in cells and achieved Cu2+-ion dete...

In this work, an open-tubular capillary liquid-phase column was prepared by modifying chain polymer on the inner surface of capillary and chemical bonding of metal organic frameworks, NH2 -UiO-66, to the brushes of chain polymer (poly(glycidyl methacrylate)). Besides advantages of facial preparation and good permeability, the chain polymer effectively increases the modification amount of NH2 -UiO-66 nanoparticles to increase the phase ratio of open-tubular capillary column and enhance the interactions with analytes. The results of scanning electron microscope energy-dispersive X-ray spectra indicated that NH2 -UiO-66 nanoparticles were successfully bonded to the chain polymer. Because of the hydrophobic interaction and hydrogen bonding interaction between the analytes and the ligand of NH2 -UiO-66, different analytes were well separated on the NH2 -UiO-66-modified poly(glycidyl methacrylate) capillary (1.12 m × 25 μm id × 365 μm od) with the high absolute column efficiency reaching 121 477 plates, benefiting from an open-tubular column and low mass transfer resistance provided by polymer brush and metal-organic framework crystal. The relative standard deviations of the retention time for run-to-run, day-to-day, and column-to-column (n = 3) runs are below 4.28%, exhibiting good repeatability. Finally, the column was successfully applied to separation of flavonoids in licorice.

Based on density differences of different subpopulations of exosomes, two kinds of micro-vesicles with different densities were captured from urine by a modified sucrose density gradient ultracentrifuge separation method. Verified by transmission electron microscope (TEM) and western blot, the results showed these two kinds of micro-vesicles were all exosomes. And these two kinds of exosomes were analyzed by TEM, 2D electrophoresis (2DE), and capillary zone electrophoresis (CZE), respectively. The results of TEM showed these two exosomes with different densities have different morphological characteristics, and some tiny proteomic differences were shown in the results of 2DE of these two exosomes. At the same time, the CZE results displayed these two kinds of exosomes possessed different retention times, indicated that they may have different electrification property and particle weight. These results may attribute to their different origins. This work may provide a preliminary experience for the origin-tracking study for urinary exosomes, and would be more useful for future targeted biomarker discovery.

Background Adipose-derived stem cells (ADSCs) are an attractive cell source for bone tissue engineering and have great potential for bone regeneration and defect repair. The transcriptional coactivator with PDZ-binding motif (TAZ) has been demonstrated to modulate osteogenic and adipogenic differentiation of mesenchymal stem cells. However, its roles during ADSC differentiation and therapeutic potentials for bone regeneration have as yet not been well established. Methods TAZ expression was measured during osteogenic differentiation of ADSCs in vitro. Both loss-of-function and gain-of-function approaches by TAZ knockdown or enforced overexpression were utilized to determine its functions during osteogenic differentiation of ADSCs. TM-25659, a chemical activator of TAZ, was used to determine whether pharmacological activation of TAZ in ADSCs enhanced osteogenic differentiation in vitro and bone formation in animal models. The molecular mechanisms underlying TAZ in promoting osteogenesis of ADSCs were also explored. Results Increased TAZ expression was observed during osteogenic differentiation of human ADSCs. TAZ knockdown resulted in compromised osteogenic differentiation and enhanced adipogenic differentiation of ADSCs. In contrast, enforced TAZ overexpression yielded increased osteogenic differentiation and bone regeneration in vivo, and impaired adipogenic differentiation of ADSCs. Pharmacological activation of TAZ by its chemical activator TM-25659 facilitated osteogenic differentiation of ADSCs. Noticeably, transient treatment of ADSCs with TM-25659 or intraperitoneal injection of TM-25659 significantly enhanced bone regeneration of ADSCs loaded with porous β-TCP in vivo. Mechanistically, TM-25659 exposure significantly promoted TAZ phosphorylation and nuclear translocation, and potentiated the assembly of the TAZ-Runx2 complex. Subsequently, the TAZ-Runx2 complex was further recruited to the promoter of osteocalcin and in turn enhanced its transcription. Conclusions Our findings indicate that TAZ is a key mediator that promotes ADSC commitment to the osteoblast lineage. Pharmacological activation of TAZ in ADSCs might become a feasible and promising approach to enhance bone regeneration and repair. Electronic supplementary material The online version of this article (10.1186/s13287-018-0799-z) contains supplementary material, which is available to authorized users.

Surface-enhanced Raman scattering (SERS) has wide applications because of its high sensitivity, convenience, rapid detection and numerous vibrational spectroscopic fingerprints. In this study, silver nanoparticle-incorporated ultralong hydroxyapatite nanowires (HAPNWs) as SERS substrates were used for highly sensitive SERS detection. HAPNWs were used to prepare AgNPs in situ using an aqueous solution containing AgNO3 under sunlight at room temperature without adding a reducing agent. The as-prepared highly flexible HAP nanowires were adopted for the fabrication of free-standing paper-like materials. The as-prepared ultralong HAP nanowires loaded with AgNPs not only possessed the merits of high flexibility and a porous network structure, but also exhibited unique characteristics of an SERS substrate including stability, convenience, and simple and environmentally friendly preparation. We discussed the fabrication, physical characterization and SERS activity of our SERS paper by measuring the Raman signals for a variety of model analytes. The SERS substrate was found to be highly sensitive and amiable to several different target analytes. The substrate also showed high stability and reproducibility. Subsequently, the potential practical application of the SERS paper was evaluated by quantitative analysis of an organic pollutant benzidine with an internal reference in environmental samples. Good linearity was demonstrated between 0.4 and 6.0 μM for benzidine with a correlation coefficient of 0.9919, and the limit of detection was 0.2 μM. The recovery ranged from 117% to 140% for benzidine in environmental water. These results indicated promising potential of the HAPNWs@AgNP paper as the SERS substrate for trace environmental pollutant detection.

The structural regularity, atomically precise design, high surface area and adsorption affinity make covalent-organic frameworks (COFs) attractive as novel stationary phases in chromatography. In this paper, an in situ growth strategy was developed to synthesize a COF–silica composite (SiO2@COF5 microspheres) by modifying COF5 onto silica particles (5 μm) as the stationary phase for HPLC separation. The COF5 shell was constructed from benzene-1,4-diboric acid and 2,3,6,7,10,11-hexahydroxytriphenylene. The in situ growth of the COF5 shell not only on the particle surface but also inside the pore of the SiO2 particles overcomes the shortcomings of the irregular morphology of the COF and high back pressure from the sub-micrometer size of the COF, facilitating its application in HPLC. The enthalpy change and entropy change of analytes (alkyl benzenes and polycyclic aromatic hydrocarbons) during the separation with SiO2@COF5 as the stationary phase were first measured by varying the column temperature to investigate the retention mechanism. The enthalpy change and entropy change were found different from commercial C18 columns, suggesting the contribution of the three-dimensional structure of SiO2@COF5 microspheres. The SiO2@COF5 packed column (150 mm × 2.1 mm i.d.) showed excellent selectivity for alkyl benzenes, polycyclic aromatic hydrocarbons, anilines, acetophenones, benzaldehydes and isomers of hydroxyacetophenone. The SiO2@COF5 packed column also showed good repeatability with relative standard deviations of retention time and peak height below 5%.

Protein glycosylation has been demonstrated to be associated with numerous diseases. Taking into consideration of low abundance of N-linked glycans, the pretreatment of a biological sample is a key problem. In this study, a highly ordered mesoporous carbon material was prepared using SBA-15 as a hard template and poly-dopamine as a carbon source. The material showed ordered mesoporous structure, high specific area (1223 m2 g−1) with a pore size of 2.67 nm, high selectivity for glycans from glycoprotein, and good chemical inertness and mechanical strength. Based on the specific interaction between the carbon material and glycans and the size-exclusive mechanism, 25 N-linked glycans from OVA digest were efficiently captured. In addition, 30 N-linked glycans were selectively captured from human serum, which indicated that the prepared material is a promising tool in protein glycosylation research.

In this work, recyclable trypsin immobilized magnetic nanoparticles based on hydrophilic branched polyethylenimine (PEI) modification were synthesized under mild conditions. The amount of the immobilized enzyme was increased greatly by introducing branched PEI onto poly(methacrylic acid) (PMAA) modified Fe3O4 microspheres (denoted as Fe3O4@PMAA@PEI). Trypsin, a model enzyme for this study, was immobilized by Cu2+ with metal chelation to Fe3O4@PMAA@PEI. Compared with Fe3O4@PMAA nanoparticles, the abundant amino groups of the PEI layer not only increased the amount of the immobilized enzyme, but also improved the hydrophilicity of the material to avoid nonspecific protein adsorption. The performance of this material was evaluated by digesting bovine serum albumin (BSA), myoglobin and cytochrome C, followed by MALDI-TOF-MS analysis. Compared with in-solution digestion, not only the sequence coverage was improved (70.0 ± 3.1% vs. 40.0 ± 2.3% for BSA, 92.0 ± 2.4% vs. 81.0 ± 0.8% for myoglobin and 90.0 ± 3.0% vs. 56.0 ± 1.8% for cytochrome C), but also the digestion time was decreased from 24 h to 10 min. Furthermore, the relative standard deviation values (RSDs) of the sequence coverage of BSA were 3.0% for five consecutive digestions and 2.2% for particles from different batches (n = 3), showing good reproducibility. The Fe3O4@PMAA@PEI-trypsin can endure at least 7 times usage and still maintain good digestion performance after being stored at 4 °C for 25 days. When applied to complex samples, more proteins were identified from the extract of a rat liver than in-solution based digestion (582 vs. 496), with a shorter reaction time of 10 min.

Previous in vivo and in vitro studies have linked perfluorinated compound (PFC) exposure with metabolic interruption, but the inter-species difference and high treatment doses usually make the results difficult to be extrapolated to humans directly. The best strategy for identifying the metabolic interruption may be to establish the direct correlations between monitored PFCs data and metabolic data on human samples. In this study, serum metabolome data and PFC concentrations were acquired for a Chinese adult male cohort. The most abundant PFCs are PFOA and PFOS with concentration medians 7.56 and 12.78 nM, respectively; in together they count around 81.6% of the total PFCs. PFC concentration-related serum metabolic profile changes and the related metabolic biomarkers were explored by using partial least squares-discriminant analysis (PLS-DA). Respectively taking PFOS, PFOA and total PFC as the classifiers, serum metabolome can be differentiated between the lowest dose group (1st quartile PFCs) and the highest PFC dose group (4th quartile PFCs). Ten potential PFC biomarkers were identified, mainly involving in pollutant detoxification, antioxidation and nitric oxide (NO) signal pathways. These suggested that low-level environmental PFC exposure has significantly adverse impacts on glutathione (GSH) cycle, Krebs cycle, nitric oxide (NO) generation and purine oxidation in humans. To the best of our knowledge, this is the first report investigating the association of environmental PFC exposure with human serum metabolome alteration. Given the important biological functions of the identified biomarkers, we suggest that PFC could increase the metabolism syndromes risk including diabetes and cardiovascular diseases.

Two kinds of fluorescent nano-probes (pH-A and pH-B) with different diameters for the determination of H+ concentration, based on photo-induced electron transfer mechanism, were synthesized through click reaction. In which 1,8-naphthalimide was employed as the fluorophore and N,N-dimethylethylenediamine as the receptor. The effects of particle size and linker length on the photophysical properties of the probe were studied. The results revealed that the nano-probes were more sensitive toward pH with increasing particle size. The fluorescence intensity at 529 nm (I529) of the nano-probe pH-A of 120 nm exhibited good linear relationship with solution’s pH in the range of 6–8. The probe pH-A displayed excellent selectivity and competition toward proton over other possible coexisted ions, and it could be applied to detect pH in realistic samples (river water, urine).

Protein methylation as one of the most important post-translational modifications has been under the spotlight due to its essential role in many biological processes. Development of methods for large-scale analysis of protein methylation greatly accelerates the related researches. To date, antibody-based enrichment strategy is the most common approach for methylproteomics analysis. However, it is still lacking of a pan-specific antibody to enrich peptides or proteins carrying all kinds of lysine and arginine methylation forms. Herein, an online basic strong cation exchange chromatography was developed to enrich methylated peptides from protein digests prepared by two complementary methods, including direct multiple enzymes digestion and carboxylic amidation followed by multiple enzymes digestion. After enrichment, the majority of identifications were obtained from direct multiple enzymes digested sample. The enrichment specificity of methylated peptides was up to 28.5%, and 445 methylation forms corresponding to 376 methylation sites were identified on 194 proteins in one LC-MS/MS run using only 100 μg of digests. This method has great potential in studying protein methylation mediated biological processes.

Single-molecule magnets in cobalt clusters is much less well known than it is in manganese(II)/(III)/(IV) clusters. To explore new types of cobalt clusters and their potential applications, a new mixed valence coordination polymer ([Co(III)3Co(II)2(mba)6(Hdtba) (H2O)4]n, H2dtba=2,2’-dithiodibenzoic acid, H2mba=2-mercaptobenzoic acid) (1) is constructed by employing cobalt chloride hexahydrate and H2mba as starting reactants under hydrothermal conditions. Single-crystal XRD studies indicate that 1 consists of a trinuclear cobalt(III)-sulfur cluster moiety and two discrete cobalt(II) nodes, which result in the formation of a covalent three-dimensional complex network. Similarly, the cobalt(III) cluster moiety acts as a building unit in this infinite coordination polymer 1 instead of the discrete and tiara-like clusters previously reported in the literature. Magnetic studies show its slow magnetic relaxation in the absence of an applied dc field, which is characteristic behavior of single-ion magnets, caused by the individual Co(II) ions.

A fluorescent probe NFP-G, with β- d -galactose as the targeted unit and hydrazine as the recognition group for formaldehyde (FA), was designed and synthesized for specifically detecting endogenous FA in HepG-2 cells via asialoglycoprotein receptor-mediated endocytosis. The experimental results show that probes NFP-G/NFP-A exhibited highly fluorescent responses toward FA, which could be ascribed to the restriction of the photoinduced electron transfer (PET) process by the formation of hydrazone. Good selectivity and competition of NFP-G toward FA over potentially interfering species ensure it an appropriate candidate for FA detection. The sensing mechanism of the probes toward FA was studied by theoretical calculation, high performance liquid chromatography and mass spectrum. The confocal bioimaging results reveal that NFP-G could selectively visualize the endogenous FA in asialoglycoprotein receptor overexpressed HepG-2 cells over other cells. Pretreated with β-galactosidase made both asialoglycoprotein receptor positive and negative cells display strong green fluorescence, revealing β- d -galactose is essential in targeting HepG-2 cells.

•Perfect vortex beams are generated by using novel phase holograms based on Bessel function.•Perfect vortex beams are transmitted effectively for a certain distance.•Perfect vortex beams are applied to the field of free space optical communication.

Airborne fine particulate matter (PM2.5) pollution is a serious environmental problem, thus it is very important to study the toxicity effect and mechanism of PM2.5. In this study, liquid chromatography-mass spectrometry (LC-MS)-based metabolomics technique was used to investigate the metabolic disruption effect and reproductive toxicity mechanism of PM2.5 on rat testis. The profile of aqueous and organic testis metabolic extracts were acquired, and then analyzed by partial least square-discriminant analysis and nonparametric test. The results showed that control group and treatment group were clearly discriminated in the scoring plot of partial least squares discriminant analysis (PLS-DA) models, indicating PM2.5 treatment induced significant difference in testis metabolome, a total of 56 differential metabolites were identified, and further pathway analysis suggested that PM2.5 exposure induced amino acid and nucleotide metabolism disorder, steroid hormone metabolism imbalance and abnormal lipid metabolism. These important pathways may be the key molecular evens in the PM2.5 reproductive toxicity.

For in-depth analysis of phosphorylated proteomics, the highly sensitive and selective capture of phosphopeptides from intricate biological samples is extremely significant. In this work, a late-model immobilized metal ion affinity chromatography (IMAC) material was fabricated and applied to enriching phosphopeptides from biological samples by abundant Ti4+ ions, which were chelated to crosslinked chitosan (CS) loaded on the surface of magnetic graphene oxide (GO) (denoted as mag GO–CS–Ti4+). The high amount of crosslinked CS endowed the IMAC material with highly hydrophilic properties and abundant active sites for Ti4+ ions on the surface. These characteristics ensure the great performance of mag GO–CS–Ti4+ in the selective enrichment of phosphopeptides from the tryptic digest of β-casein with high selectivity (phosphopeptides to non-phosphopeptides at a molar ratio of 1 : 400), high sensitivity (0.5 fmol), large enrichment capacity (66.6 mg g−1), prominent phosphopeptide recovery (93.11%), and excellent reusability. What's more, mag GO–CS–Ti4+ was applied to capturing phosphopeptides from real biological samples, human serum from both healthy people and patients and nonfat milk. The results successfully manifested that the mag GO–CS–Ti4+ could be a great affinity material for the enrichment of low-abundant phosphopeptides from biological samples.

A fluorescence "off-on" probe CBF, constructed by incorporating a dioxaborine unit into a microenvironment-sensitive fluorophore, was developed for serum albumin (SA). Upon binding to SA, the dioxaborine group in CBF was hydrolyzed into β-diketonate, which triggered dramatic fluorescence enhancement (over 1000-fold) along with a remarkable blue-shift (∼100 nm). The bioimaging results suggested that more SA were taken in by cancer cells.

A C18-sulfonic group dual modification chromatographic stationary phase was prepared by one-pot reaction to modify the surface of silica with two modifier of octadecyltrichlorosilane (OTS) and trimethoxysilylpropanethiol (MPS), and then oxidize the thiol group. Under the optimized reaction conditions, the stationary phase with a mole ratio of 3:7 between C18 and sulfonic group was obtained. The morphology and feature of the stationary phase were characterized by scanning electronic microscopy, elemental analysis and infrared spectra. The chromatographic properties of the prepared stationary phase were systematically investigated in different separation modes. Five alkyl benzenes and three nucleosides were separated successfully by reversed phase chromatography and hydrophilic interaction chromatography, respectively. The bovine serum albumin digest was also well separated on the stationary phase. The results indicated that the prepared mixed-mode stationary phase could provide multiple separation mechanism and had potential advantages in separating complex samples and adjusting the selectivity.

In consideration of the close connection between glycopeptides and human diseases, the efficient method to separate and enrich glycopeptides from complex biological samples is urgently required. In the work, we developed a magnetic zwitterionic-hydrophilic material for highly effective separation and analysis of glycopeptides from complex samples. The Fe3O4 particles were covered with a thick layer of polymer by one-step reflux-precipitation polymerization (RPP), subsequently decorated by Au nanoparticles (Au NPs) through in situ reduction and finally modified with zwitterionic groups. The abundant zwitterionic sites facilitate the selective enrichment of glycopeptides. Besides, the prepared Fe3O4@PGMA@Au-l-cys showed high detection sensitivity (5 fmol IgG digest), approving enrichment capacity (75mgg-1), satisfactory enrichment recovery (89.8%), and great performance in the analysis and profiling of low-abundance N-linked glycopeptides. Furthermore, the prepared material was employed in the enrichment of glycopeptides in intricate biological samples, and 774 unique N-glycosylation sites from 411 N-glycosylated proteins were reliably identified in three replicate analyses of a 75μg protein sample extracted from mouse liver, suggesting wide application prospect in glycoproteomics.

Magnetic mesoporous carbon composites incorporating hydrophilic metallic nanoparticles were synthesized from resol, ZrO(NO3)2, ferric acetylacetonate, and triblock copolymer F127. The method involves a multi-component co-assembly strategy associated with direct carbonization. The resulting carbon material is shown to be useful as a metal oxide affinity chromatography (MOAC) material for enrichment of phosphopeptides owing to its large mesoporous (4.8 nm) surface area (442 m2 g−1), large pore volume (0.37 cm3 g−1) and excellent hydrophilicity. The metallic iron and ferric oxide particles modified on the mesoporous carbon exert a magnetic force and, in combination with the metallic zirconia, is a viable MOAC material for enrichment of low-abundance phosphopeptides. Because of metal chelation between metallic nanoparticles and the phosphate groups of phosphopeptides, the zirconia/magnetic mesoporous carbon displays high selectivity even at a phosphopeptide/nonphosphopeptide molar ratio of 1:500. As little as 1.5 fmol of phosphopeptides become detectable. The MOAC was successfully applied to the identification by MALDI-TOF MS of phosphopeptides in human serum and nonfat milk.

The bottom up strategy has drawn much attention due to the high accuracy, reliability, and reproducibility in protein identification in which proteins are digested into peptides. However, conventional solution-based digestion and enzymatic reactor with one protease immobilized cannot satisfy high throughput proteolysis of complex samples. Application of consecutive hydrolysis by enzymatic reactor can be a new strategy for high throughput proteolysis of complex samples by adjusting immobilization amount of the enzymes, enzyme ratio, as well as hydrolysis order of two enzymes. In this work, we propose immobilized enzymatic reactor for consecutive digestion with two enzymes by combining two enzyme reactors with trypsin and chymotrypsin immobilized, respectively. Each reactor was prepared individually by immobilizing only one protease (trypsin or chymotrypsin) to hybrid monolith with SBA-15 particles embedded. Proteolysis conditions including hydrolysis order and trypsin to chymotrypsin ratio etc. were studied using standard proteins. Best digestion performance was obtained when the proteins were digested by trypsin first with trypsin to chymotrypsin ratio of 1:1. When applying them to digestion of rat liver proteins, total 1651 proteins and 11011 peptides were identified by combining four enzymolysis strategies with two enzymes including proteolytic digestion in two consecutive enzymatic reactors, synergy enzymolysis with two enzymes in one immobilized enzymatic reactor and consecutive hydrolysis with two enzymes in-solution digestion respectively, in which consecutive enzymolysis in enzymatic reactors gave the best results with 1091 proteins and 5071 peptides identified. The reactors showed good digestion capability for proteins with different hydrophobicity and molecular weights, and will play an important role in high efficient and high throughput proteomics research.

A polarity-sensitive fluorescent probe MNP was rationally designed and synthesized with naphthalimide as the fluorophore and maleimide as the receptor for thiols. MNP is weakly fluorescent due to the photoinduced electron-transfer (PET) from the fluorophore to the receptor, and it displays evidently solvatochromic UV–vis and fluorescence spectra: the emission shifted from 495 nm in n -hexane to 545 nm in phosphate buffer solution. Michael addition reaction between thiols and the maleimide in MNP inhibited the PET process, which led to about eight-fold fluorescence enhancement. In addition, MNP showed highly sensitivity to mercapto-containing proteins and it could detect as low as 20.4 μg/mL of BSA in PBS. MNP has potential in fluorescent imaging of thiols in living cells.

Highly sensitive and selective enrichment of endogenous peptides or proteins from complex bio-system takes a significant important place to the proteomic. In this work, a unique Fe 3 O 4 @2SiO 2 @mSiO 2 -C nanomaterial was synthesized, contributing to the separation and enrichment of low concentration peptides from complex mixture. The highly ordered mesoporous carbon structure render the nanospheres with unique properties of strongly connected pore channels, strong hydrophobic properties, high specific surface area (254.90 m 2 /g), uniform pore size (3.61 nm). Which made it a promising candidates for the efficient enrichment of peptides through hydrophobic-hydrophobic interaction with low detection limit (0.2 fmol), superb size-exclusion of high molecular weight proteins, highly selectivity for BSA digest (molar ratio of BSA tryptic digests/BSA, 1:400), ideal peptides recovery (about 87.5%), wonderful repeatability (RSD less than 25%). Moreover, the as-prepared Fe 3 O 4 @2SiO 2 @mSiO 2 -C nanoparticles were successfully enriched 2198 endogenous peptides from human serum, which fully indicated that the mesoporous carbon nanoparticles was a promising candidate for isolating proteins or peptides from complex biologicals.

In this study, a standard addition–isotope dilution mass spectrometry (SA-IDMS) method for quantification of endogenous progesterone in milk has been described. The method validation results, linearity, limits of detection and quantification, recovery and uncertainty were fit for the purpose of assigning reference mass fractions to proficiency testing schemes. The developed technique was compared to the isotope dilution mass spectrometry (IDMS) method already existing in the laboratory. Analytical results of two milk samples were (1.377 ± 0.048) μg/kg and (4.457 ± 0.155) μg/kg by SA-ID-LC/MS method, while the results were (1.355 ± 0.019) μg/kg and (4.359 ± 0.059) μg/kg by ID-LC/MS, respectively. Since SA-IDMS was an effective quantitative method that overcame matrix effect, similar quantitative results from IDMS and SA-IDMS indicated that the quantification of progesterone in milk was barely influenced by matrix. Both IDMS and SA-IDMS could be used to assign reference mass fractions to progesterone in milk inter-laboratory proficiency testing schemes.

Objective: This study aims to evaluate the pharyngeal airway dimensions among Chinese adults in relation to Class I and Class II facial skeletal patterns using three-dimensional cone-beam computed tomography (CBCT) images. Materials and Methods: A total of 156 initial CBCT images were evaluated, which were classified into skeletal Class I and Class II according to ANB angle with mean (SD) age being 22.56 ± 4.0 years and 22.32 ± 3.6 years. The pharyngeal airway volume, airway area, minimum cross-sectional area (MCA) and the distance from uvula (tip of the soft palate) to mental spine (U-MS distance) were assessed with Dolphin imaging software. Results: Compared with Class I group, Class II group displayed significantly smaller pharyngeal airway volume, airway area and MCA (P

Mechanical force across sutures is able to promote suture osteogenesis. Orthodontic clinics often use this biological characteristic of sutures to treat congenital cranio-maxillofacial malformations. However, the underlying mechanisms still remain poorly understood. Craniofacial sutures provide a special growth source and support primary sites of osteogenesis. Here, we isolated rat sagittal suture cells (rSAGs), which had mesenchymal stem cell characteristics and differentiating abilities. Cells were then subjected to mechanical tension (5% elongation, 0.5 Hz; sinusoidal waveforms) showing that mechanical tension could enhance osteogenic differentiation but hardly affect proliferation of rSAGs. Besides, mechanical tension could increase Rho-associated kinase (ROCK) expression and enhance transcriptional coactivator with PDZ-binding motif (TAZ) nuclear translocation. Inhibiting ROCK expression could suppress tension-induced osteogenesis and block tension-induced upregulation of nuclear TAZ. In addition, our results indicated that TAZ had direct combination sites with runt-related transcription factor 2 (Runx2) in rSAGs, and knock-downed TAZ simultaneously decreased the expression of Runx2 no matter with or without mechanical tension. In summary, our findings demonstrated that the multipotency of rSAGs in vitro could give rise to early osteogenic differentiation under mechanical tension, which was mediated by ROCK-TAZ signal axis.

We report here high-level ab initio calculations for [LnO], Ln=Tb, Dy, Ho, which show that divalent lanthanides can exhibit equally strong magnetic anisotropy and magnetization blocking barriers.

Free-flow isoelectric focusing (FFIEF) has the merits of mild separation conditions, high recovery and resolution, but suffers from the issues of ampholytes interference and high cost due to expensive carrier ampholytes. In this paper, a home-made carrier ampholyte-free FFIEF system was constructed via orientated migration of H+ and OH- provided by electrode solutions. When applying an electric field, a linear pH gradient from pH 4 to 9 (R2 = 0.994) was automatically formed by the electromigration of protons and hydroxyl ions in the separation chamber. The carrier ampholyte-free FFIEF system not only avoids interference of ampholyte to detection but also guarantees high separation resolution by establishing stable pH gradient. The separation selectivity was conveniently adjusted by controlling operating voltage and optimizing the composition, concentration and flow rate of the carrier buffer. The constructed system was applied to separation of proteins in egg white, followed by MADLI-TOF-MS identification. Three major proteins, ovomucoid, ovalbumin and ovotransferrin, were successfully separated according to their pI values with 15 mmol/L Tris-acetic acid (pH = 6.5) as carrier buffer at a flow rate of 12.9 mL/min.