Search

Since December 2019, the coronavirus disease 2019 (COVID-19) has become a global pandemic. Currently, the COVID-19 pandemic is still ongoing. What changes have taken place in the obesity and obesity-related lifestyle behaviours of adolescents during the first year of the COVID-19 pandemic?This study aims at analysing the changes in obesity and lifestyle behaviours of Chinese adolescents before and 1 year after the outbreak of the COVID-19 pandemic, providing evidence for the global strategies to respond to the impact of the COVID-19 pandemic on adolescent obesity.Physical examinations and student health and influencing factors questionnaires were conducted among 6047 adolescents aged 11-16 years by health professionals in Shanghai, China, before the COVID-19 pandemic (September-November of 2019) and 1 year after the outbreak of the COVID-19 pandemic (September-November of 2020). Paired1 year after the outbreak of the COVID-19 pandemic, the obesity prevalence of Chinese adolescents rose from 14.2% to 15.4% (p 0.01), mainly because of the increase in boys. And the average BMI increased from 20.3 to 21.2 kg/mThis study found that 1 year after the outbreak of the COVID-19 pandemic, the BMI and obesity prevalence of Chinese adolescents increased and obesity-related lifestyle behaviours have also changed.

SiC fiber-reinforced SiC ceramic matrix composites (SiCf/SiC CMCs) are being increasingly used in the hot sections of gas turbines because of their light weight and mechanical properties at high temperatures. The objective of this investigation was the development of a thermal/environmental barrier coating (T/EBC) composite coating system consisting of an environmental barrier coating (EBC) to protect the ceramic matrix composites from chemical attack and a thermal barrier coating (TBC) that insulates and reduces the ceramic matrix composites substrate temperature for increased lifetime. In this paper, a plasma spray-physical vapor deposition (PS-PVD) method was used to prepare multilayer Si–HfO2/Yb2Si2O7/Yb2SiO5/Gd2Zr2O7 composite coatings on the surface of SiCf/SiC ceramic matrix composites. The purpose of this study is to develop a coating with resistance to high temperatures and chemical attack. Different process parameters are adopted, and their influence on the microstructure characteristics of the coating is discussed. The water quenching thermal cycle of the coating at high temperatures was tested. The results show that the structure of the thermal/environmental barrier composite coating changes after water quenching because point defects and dislocations appear in the Gd2Zr2O7 and Yb2SiO5 coatings. A phase transition was found to occur in the Yb2SiO5 and Yb2Si2O7 coatings. The failure mechanism of the T/EBC composite coating is mainly spalling when the top layer penetrates cracks and cracking occurs in the interface of the Si–HfO2/Yb2Si2O7 coating.

Semi-transparent solar cells can be used for spectral beam splitting (SBS) in which short-wavelength photons are converted to electricity and long-wavelength photons are transmitted to thermal absorbers. However, these thermal absorbers can only produce low-grade thermal energy because the semi-transparent solar cell cannot concentrate long-wavelength photons. In this study, based on the idea of regulating the radiation field to match the energy conversion on-demand, the strategy to use a single piece of photovoltaic (PV) to regulate the photon capture of the full solar spectrum for realizing the co-generation of electricity and high-grade thermal energy is proposed. A semi-transparent solar cell with a serrated groove structure at the bottom is designed and fabricated. The cell can convert 400–800 nm wavelength photons to electricity, and focus 800–2500 nm wavelength photons to a small spot to produce high-temperature thermal energy. A novel α-Si thin-film semi-transparent solar cell-based SBS hybrid photovoltaic/concentrated solar thermal system is established. The feasibility of the system is validated through indoor and outdoor experiments. The utilization efficiency of the full-spectrum solar energy can reach 77%. The high average concentrated irradiance of up to 4.31 KW/m2 transmitted through the semi-transparent solar cells is sufficient for high-temperature thermal utilization.

Pancreatic cancer is among the deadliest malignancies; however, the genetic events that lead to pancreatic carcinogenesis in adults remain unclear. In vivo models in which these genetic alterations occur in adult animals may more accurately reflect the features of human cancer. In this study, we demonstrate that inactivation of Cdkn2b (p15ink4b) is necessary for induction of pancreatic cancer by oncogenic KRASG12D expression and inactivation of Tp53 and Cdkn2a in adult mouse pancreatic ductal cells (P60 or older). KRASG12D overexpression in these cells activated transforming growth factor-β signaling and expression of CDKN2B, which, along with CDKN2A, led to cellular senescence and protected cells from KRAS-mediated transformation via inhibition of retinoblastoma phosphorylation. These results show a critical role of CDKN2B inactivation in pancreatic carcinogenesis, and provide a useful adult animal model by genetic engineering via lentiviral delivery.

The persistence of cholesterol-engorged macrophages (foam cells) in the artery wall fuels the development of atherosclerosis. However, the mechanism that regulates the formation of macrophage foam cells and impedes their emigration out of inflamed plaques is still elusive. Here, we report that adhesion receptor CD146 controls the formation of macrophage foam cells and their retention within the plaque during atherosclerosis exacerbation. CD146 is expressed on the macrophages in human and mouse atheroma and can be upregulated by oxidized low-density lipoprotein (oxLDL). CD146 triggers macrophage activation by driving the internalization of scavenger receptor CD36 during lipid uptake. In response to oxLDL, macrophages show reduced migratory capacity toward chemokines CCL19 and CCL21; this capacity can be restored by blocking CD146. Genetic deletion of macrophagic CD146 or targeting of CD146 with an antibody result in much less complex plaques in high-fat diet-fed ApoE−/− mice by causing lipid-loaded macrophages to leave plaques. Collectively, our findings identify CD146 as a novel retention signal that traps macrophages within the artery wall, and a promising therapeutic target in atherosclerosis treatment.

Magneto-rheological fluid has controllable rheological properties, as a result, the compliant joint of robots based on it has active variable stiffness transmission characteristics. Magneto-rheological compliant joint coupler is a key transmission component of the compliant joint of robots which designed based on magneto-rheological fluid shear transmission mode. Due to inherent nonlinear characteristics such as time-varying parameters, hysteresis and magnetization saturation, it is of great difficulties to establish an accurate mathematical model. A magneto-rheological compliant joint coupler torque control method based on fuzzy adaptive PID algorithm was proposed, a smooth joint coupler drive system experimental platform was established, a torque control interface of compliant joint coupler transmission system designed on NI LabVIEW was developed, the torque control experiments based on fuzzy adaptive PID algorithm and conventional PID algorithm were done respectively. The consequence reveals that compared with the conventional PID algorithm, the conventional PID algorithm has more excellent velocity of response trait and more stabilized peculiarity, and the control effect also shows better.

Nanobodies consist of a single domain variable fragment of a camelid heavy-chain antibody. Nanobodies have potential applications in biomedical fields because of their simple production procedures and low cost. Occasionally, nanobody clones of interest exhibit low affinities for their target antigens, which, together with their short half-life limit bioanalytical or therapeutic applications. Here, we developed a novel platform we named fenobody, in which a nanobody developed against H5N1 virus is displayed on the surface of ferritin in the form of a 24mer. We constructed a fenobody by substituting the fifth helix of ferritin with the nanobody. TEM analysis showed that nanobodies were displayed on the surface of ferritin in the form of 6 × 4 bundles, and that these clustered nanobodies are flexible for antigen binding in spatial structure. Comparing fenobodies with conventional nanobodies currently used revealed that the antigen binding apparent affinity of anti-H5N1 fenobody was dramatically increased (∼360-fold). Crucially, their half-life extension in a murine model was 10-fold longer than anti-H5N1 nanobody. In addition, we found that our fenobodies are highly expressed in Escherichia coli, and are both soluble and thermo-stable nanocages that self-assemble as 24-polymers. In conclusion, our results demonstrate that fenobodies have unique advantages over currently available systems for apparent affinity enhancement and half-life extension of nanobodies. Our fenobody system presents a suitable platform for various large-scale biotechnological processes and should greatly facilitate the application of nanobody technology in these areas.

The apical–basal (AB) polarity and planar cell polarity (PCP) provide an animal cell population with different phenotypes during morphogenesis. However, how cells couple these two patterning systems remains unclear. Here we provide in vivo evidence that melanoma cell adhesion molecule (MCAM) coordinates AB polarity-driven lumenogenesis and c-Jun N-terminal kinase (JNK)/PCP-dependent ciliogenesis. We identify that MCAM is an independent receptor of fibroblast growth factor 4 (FGF4), a membrane anchor of phospholipase C-γ (PLC-γ), an immediate upstream receptor of nuclear factor of activated T-cells (NFAT) and a constitutive activator of JNK. We find that MCAM-mediated vesicular trafficking towards FGF4, while generating a priority-grade transcriptional response of NFAT determines lumenogenesis. We demonstrate that MCAM plays indispensable roles in ciliogenesis through activating JNK independently of FGF signals. Furthermore, mcam-deficient zebrafish and Xenopus exhibit a global defect in left-right (LR) asymmetric establishment as a result of morphogenetic failure of their LR organizers. Therefore, MCAM coordination of AB polarity and PCP provides insight into the general mechanisms of morphogenesis., It is unclear if there is an interaction between apical-basal (AB) polarity and planar cell polarity (PCP) pathways during morphogenesis. Here, the authors define a role for the melanoma cell adhesion molecule (MCAM), known to regulate PCP, in AB polarity via FGF signalling in vitro and in zebrafish.

Background Busulfan/cyclophosphamide (Bu/Cy) is commonly used as a standard conditioning regimen without total body irradiation for patients with hematological myeloid malignancies undergoing hematopoietic stem cell transplantation (HSCT). Objective To develop a new myeloablative conditioning regimen incorporating fludarabine (Flu) and cytarabine (Ara-c). Setting A tertiary blood disease hospital in Tianjin, China. Methods A Bu/Cy preparative regimen was used, modified by Flu 90 mg/m2 and Ara-c 6 g/m2 in 57 unselected patients (median age 37 years) with hematological myeloid malignancies. The patients were to receive allogeneic hematopoietic stem cell transplantation (allo-HSCT). Thirteen patients had high-risk leukemia, fifty patients had HLA matched sibling donors while seven patients had HLA mismatched sibling donors. Cy was given 50 mg/kg/day for 2 days while Bu was given 3.2 mg/kg/day intravenously for 3 days. Main outcome measure Post-transplant donor chimerism, relapse tendency and minimal residual disease. Results Extramedullar toxicity was relatively limited; the incidence of treatment-related mortality (TRM) within 100 days was 3.5 %. The incidence of grade II–IV, grade III–IV acute graft versus host disease (GVHD) and chronic GVHD of the evaluable patients were 21.1, 8.8 and 36.4 %, respectively. With a median follow up of 59 (13–96.5) months, TRM and relapse rate (RR) at eight years were 24.1 ± 5.8 and 14.7 ± 4.8 %, respectively. Disease free survival at eight years was 67.9 ± 6.2 % for the entire group, 60.0 ± 8.9 % for patients with AML, 77.3 ± 8.9 % for patients with CML, 70.0 ± 6.5 and 42.9 ± 18.7 % or matched sibling and mismatched sibling HSCT respectively. Conclusion The new regimen was associated with a low relapse rate, low incidence and severity of graft versus host disease and satisfactory survival for patients with myeloid malignancies.

The cell adhesion molecule CD146 is a novel inducer of epithelial–mesenchymal transition (EMT), which was associated with triple-negative breast cancer (TNBC). To gain insights into the complex networks that mediate CD146-induced EMT in breast cancers, we conducted a triple Stable Isotope Labeling with Amino Acids in Cell Culture (SILAC), to analyze whole cell protein profiles of MCF-7 cells that had undergone gradual EMT upon CD146 expression from moderate to high levels. In this study, we identified 2293 proteins in total, of which 103 exhibited changes in protein abundance that correlated with CD146 expression levels, revealing extensive morphological and biochemical changes associated with EMT. Ingenuity Pathway Analysis (IPA) showed that estrogen receptor (ER) was the most significantly inhibited transcription regulator during CD146-induced EMT. Functional assays further revealed that ER-α expression was repressed in cells undergoing CD146-induced EMT, whereas re-expression of ER-α abolished their migratory and invasive behavior. Lastly, we found that ER-α mediated its effects on CD146-induced EMT via repression of the key EMT transcriptional factor Slug. Our study revealed the molecular details of the complex signaling networks during CD146-induced EMT, and provided important clues for future exploration of the mechanisms underlying the association between CD146 and TNBC as observed in the clinic. Biological significance This study used a proteomics screen to reveal molecular changes mediated by CD146-induced epithelial–mesenchymal transition (EMT) in breast cancer cells. Estrogen receptor (ER) was found to be the most significantly inhibited transcription regulator, which mediated its effects on CD146-induced EMT via repression of the transcriptional factor Slug. Elucidation of protein interaction networks and signal networks generated from 103 significantly changed proteins would facilitate future investigation into the mechanisms underlying CD146 induced-EMT in breast cancers.

FXYD6, FXYD domain containing ion transport regulator 6, has been reported to affect the activity of Na+/K+-ATPase and be associated with mental diseases. Here, we demonstrate that FXYD6 is up-regulated in hepatocellular carcinoma (HCC) and enhances the migration and proliferation of HCC cells. Up-regulation of FXYD6 not only positively correlates with the increase of Na+/K+-ATPase but also coordinates with the activation of its downstream Src-ERK signaling pathway. More importantly, blocking FXYD6 by its functional antibody significantly inhibits the growth potential of the xenografted HCC tumors in mice, indicating that FXYD6 represents a potential therapeutic target toward HCC. Altogether, our results establish a critical role of FXYD6 in HCC progression and suggest that the therapy targeting FXYD6 can benefit the clinical treatment toward HCC patients. Electronic supplementary material The online version of this article (doi:10.1007/s13238-014-0045-0) contains supplementary material, which is available to authorized users.

CD146, an endothelial biomarker, has been shown to be aberrantly upregulated during pathological angiogenesis and functions as a coreceptor for vascular endothelial growth factor receptor 2 (VEGFR-2) to promote disease progression. However, the regulatory mechanisms of CD146 expression during angiogenesis remain unclear. Using a microRNA screening approach, we identified a novel negative regulator of angiogenesis, microRNA 329 (miR-329), that directly targeted CD146 and inhibited CD146-mediated angiogenesis in vitro and in vivo. Endogenous miR-329 expression was downregulated by VEGF and tumor necrosis factor alpha (TNF-α), resulting in the elevation of CD146 in endothelial cells. Upregulation of CD146 facilitated an endothelial response to VEGF-induced SRC kinase family (SKF)/p38 mitogen-activated protein kinase (MAPK)/NF-κB activation and consequently promoted endothelial cell migration and tube formation. Our animal experiments showed that treatment with miR-329 repressed excessive CD146 expression on blood vessels and significantly attenuated neovascularization in a mouse model of pathological angiogenesis. Our findings provide the first evidence that CD146 expression in angiogenesis is regulated by miR-329 and suggest that miR-329 could present a potential therapeutic tool for the treatment of angiogenic diseases.

The soluble form of CD146 has been reported to be present in various inflammatory diseases and displays pro-inflammatory properties. However, little is known about sCD146 in multiple sclerosis (MS). Here we show that sCD146 is significantly elevated in the cerebrospinal fluid of patients with active MS compared with that of inactive MS or patients with non-demyelinating diseases. Moreover, abnormally increased sCD146 in the CSF of active MS patients correlated with albumin quotient, MBP antibody and MOG antibody from both CSF and sera. Importantly, the level of CSF sCD146 is correlated with levels of inflammatory factors, such as TNFα, IFNγ, IL-2, and IL-17A in the CSF. We also found that CSF sCD146 might originate from membrane-bound CD146 on inflamed blood-brain barrier (BBB) endothelial cells. In addition, sCD146 promotes leukocyte transmigration in vitro, at least in part by stimulating the expression of ICAM-1 and VCAM-1 on endothelial cells. Our findings suggest that CSF levels of sCD146 may provide a potential marker for monitoring disease activity in MS patients.

Despite efforts, a decline in breastfeeding rates has been documented in China recently. This study explored the awareness of the World Health Organization (WHO) guidelines for breastfeeding and intention to breastfeed among first-time mothers and identified the gap between mothers' needs and perinatal care provision regarding breastfeeding promotion.In total, 653 women at 5-22 gestational weeks were recruited from four community health centers in Shanghai, China. They completed a self-administered questionnaire at recruitment. Two focus group discussions were held among third-trimester pregnant women who had received prenatal education. Twenty-four in-depth interviews were conducted among postpartum mothers.During early pregnancy, a substantial proportion of mothers were not aware of the nutritional value of breastmilk (40%) or the value of exclusive breastfeeding for 6 months (80%) or any breastfeeding for 24 months (98%). The awareness of the WHO guidelines for breastfeeding was associated with intention to breastfeed (adjusted odds ratio [OR] 2.67, 95% confidence interval [CI] 1.88, 3.78) or intention to breastfeed exclusively (adjusted OR 3.31, 95% CI 1.81, 6.06). In late pregnancy and postpartum, most mothers were still not fully aware of the breastfeeding recommendations and nutritional value of breastmilk. Limited communications with healthcare providers and lack of support for dealing with breastfeeding difficulties were reported.Low awareness of the WHO breastfeeding guidelines was found among first-time mothers in Shanghai. Awareness of breastfeeding guidelines was independently associated with mothers' intention to breastfeed and intention to breastfeed exclusively. The health benefits of breastfeeding and the recommended duration of breastfeeding should be emphasized in prenatal education programs.

Experiments were carried out with juvenile Amur sturgeon (Acipenser schrenckii Brandt) including two size classes [small sized (SS) and large sized (LS)] to study the effect of stocking density on the growth when reared in indoor tanks. In the first trial (SS), the juveniles (8.70 +/- 0.90 cm total length) were reared at five relatively high initial stocking densities (120, 240, 360, 480, and 600 individuals m(-3)), whereas in the second trial (LS), the larger-sized juveniles (17.31 +/- 2.05 cm total length) were reared at five relatively lower stocking densities (50, 100, 150, 200, and 250 individuals m(-3)). Thus, the density differences refer to numbers rather than biomass. Each experimental trial lasted for about 30 days. The results showed that under the same experimental conditions, the growth rate of the fish decreased with increasing stocking density. By contrast, the feed conversion rate increased gradually with increasing stocking density. There was no significant difference (P > 0.05) in the average survival rates of the fish in each group in both trials, except Group 5 in SSS (P < 0.05).

A nanoparticle-based immunoassay was developed for the rapid and sensitive detection of avian influenza virus (AIV). In this method, AIV-specific pentabody (pVHH3B) was conjugated to magnetic nanoparticles (MNPs) and used to capture AIV. Gold nanoparticles (GNPs), labelled with the anti-AIV mouse monoclonal antibody 3C8, were used as a detector. In the presence of target samples, the pentabody pVHH3B enriched AIV on the MNPs. Thereafter, mAb 3C8-labelled GNPs (GNPs-mAb3C8) bound to MNPs via AIV and were separated using a magnetic field. GNPs in the complex catalyzed the oxidation of hydroquinone to quinone, and the OD value of quinone was measured. The developed assay displayed substantial signal change after incubation in an AIV sample in a concentration-dependent manner. The detection limit was 10 ng/ml, which is 10 times more sensitive than conventional double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). In conclusion, by combining MNPs and a novel pentabody pVHH3B, this study provided a sensitive influenza viral detection assay that has the potential to become a rapid, sensitive and inexpensive diagnostic tool for infectious diseases.

Background: Cell adhesion molecules have been implicated to be up-regulated in systemic vasculitis and could be potentially used as clinical diagnostic biomarkers. As a newly identified adhesion molecule, the expression level of CD146 in vasculitis has never been determined. Methods: Clinical samples were collected and levels of soluble CD146 were measured in sera using sandwich ELISA and neutrophil CD146 using FACS analysis in 59 patients with active systemic vasculitis and 34 healthy controls. Results: Expression of CD146 was significantly elevated in circulating neutrophils of patients with active small-vessel vasculitis (WG and MPA), but not in patients with large-vessel vasculitis (TA), compared with samples from healthy controls. Interestingly, elevated levels of neutrophil CD146 were dramatically decreased after treatment with immunosuppressive drugs. Moreover, a significantly increased level of soluble CD146 was found in sera from patients with MPA and vasculitis-induced renal failure. Conclusion: The clinical study indicated that CD146 expression was elevated in active vasculitis and correlated with its pathological progression and post-treatment remission.

Researches on modified Fenton reactions applied in phenol degradation have been focused on reducing secondary pollution and enhancing catalytic efficiency. Newly developed methods utilizing carriers, such as Resin and Nafion, to immobilize Fe(2+) could avoid iron ion leakage. However, the requirement of high temperature and the limited reaction efficiency still restrained them from broad application. Based on a recently discovered "hidden talent" of ferromagnetic nanoparticles (MNPs), we established a MNP-catalyzed phenol removal assay, which could overcome these limitations. Our results showed that the MNPs removed over 85% phenol from aqueous solution within 3h even at 16 °C. The catalytic condition was extensively optimized among a range of pH, temperature as well as initial concentration of phenol and H(2)O(2). TOC and GC/MS analysis revealed that about 30% phenol was mineralized while the rest became small molecular organic acids. Moreover the MNPs were thermo-stable and could be regenerated for at least five rounds. Thus, our findings open up a wide spectrum of environmental friendly applications of MNPs showing several attractive features, such as easy preparation, low cost, thermo-stability and reusability.

We evaluated the inhibitory effect of 3,7-dinitrodibenzobromonium salts (cBr) on the proliferation of human chronic myelogenous leukemia K562 cell by trypan blue exclusion test and MTT colorimetric assay. The degree of DNA damage in K562 cells treated with cBr, was detected by isotopic tracer method (3H-TdR). The morphological changes of these K562 cells were examined by fluorescence and electron microscopy. Biochemical characteristics of K562 cells were detected by flow cytometry and 3H-thymidine incorporation assay. Findings indicated that cBr could significantly inhibit cell proliferation and result in DNA damage of K562 cells. cBr is a new type of immunostimulant and can induce cell apoptosis.

Our previous study showed that the adhesion molecule CD146 as a biomarker is over-expressed on activated endothelium during angiogenesis, which was induced by tumor conditional medium and inhibited by anti-CD146 monoclonal antibody (mAb AA98). However, the CD146 molecular organization on the cells is unknown. Here, using immunoprecipitation, we found that the dimerization of CD146 occurs in both normal and tumor cells. However, the dimer/monomer ratio was higher in tumor cells than in normal cells. Moreover, we found that CD146 dimerization was up-regulated by tumor conditional medium through the NF-kappa B pathway and down-regulated by mAb AA98. To further confirm that CD146 dimerization occurs in living cells, we used fluorescence resonance energy transfer (FRET) with melanoma Mel888 cells co-expressing CFP/YFP-tagged CD146 fusion proteins. By acceptor photobleaching, we observed a strong FRET signal produced by these two fluorescence-tagged proteins. The FRET efficiency reached 20.1%. Our data provide the first evidence that CD146 dimerization occurs in living cells and is regulated within the tumor microenvironment, implying that dimerization of CD146 may be associated with malignancy.

Our previous study showed that an anti-CD146 monoclonal antibody (mAb), AA98, which was raised against the vascular endothelial cells stimulated by a conditioned medium from hepatocarcinoma SMMC 7721 cells (SMMC 7721-CM), inhibited cell migration, angiogenesis, and tumor growth. However, the underlying mechanism was not elucidated. The objective of this study was to understand the mechanism by which mAb AA98 inhibits the endothelial cell migration and angiogenesis that is induced by SMMC 7721-CM. Using confocal imaging and biochemical studies, we found that SMMC 7721-CM induced nuclear factor κB (NF-κB) activation through the upstream p38 mitogen-activated protein kinase pathway, leading to the up-regulation of matrix metalloproteinase 9 and intercellular adhesion molecule 1 expression. Interestingly, all these activities stimulated by SMMC 7721-CM could be effectively inhibited by mAb AA98 in a dose- and time-dependent manner. Our data showed that the engagement of mAb AA98 with membrane protein CD146 inhibited p38 mitogen-activated protein kinase phosphorylation, suppressed NF-κB activation, and down-regulated matrix metalloproteinase 9 and intercellular adhesion molecule 1 expression, suggesting that the suppression of NF-κB is a critical point for the inhibitory function of mAb AA98 on endothelial cell migration, angiogenesis, and tumor metastasis. These results will provide clues for a better understanding of the mechanisms underlying tumor angiogenesis as well as antiangiogenesis therapy. [Mol Cancer Ther 2006;5(11):2872–8]

The monoclonal antibody T2-2 was originally raised against the colorectal carcinoma cell line LS174T and was found to bind to several other human carcinomas, including hepatoma and ovarian cancer. The goal of this study was to investigate the antitumor activity of mAb T2-2 in human tumor models and further characterize the antigen. mAb T2-2 inhibited the growth of human hepatocellular cell line SMMC 7721 in vivo and in vitro. Western blot analysis revealed that this mAb recognizes an unique Mr 45,000 band from tissue extracts of human hepatocellular carcinoma (HCC), which localizes to the cell periphery. In vitro cell assays indicate that T2-2 decreases cell adhesion to laminin, implying the functional role of T2-2 antigen in cell-matrix interaction and cell migration.

An immune antibody phage-display library was constructed from B cells of SARS convalescent patients. More than 80 clones were selected from the library by using the whole inactivated SARS-CoV virions as target. One human scFv, B1, was characterized extensively. The B1 recognized SARS pseudovirus in vivo and competed with SARS sera for binding to SARS-CoV with high affinity (equilibrium dissociation constant, Kd = 105 nM). The B1 also has potent neutralizing activities against infection by pseudovirus expressing SARS-CoV S protein in vitro. Finally, we found that the B1 recognized an epitope on S2 protein, especially within amino acids 1023–1189 of S2 protein. This study not only first made a human neutralizing antibody, which recognized an epitope on S2 protein like natural antibody in sera, but also may help us to better understand the immunological characteristics of SARS protein and SARS vaccine design.

An ideal nanocarrier for efficient drug delivery must be able to target specific cells and carry high doses of therapeutic drugs and should also exhibit optimized physicochemical properties and biocompatibility. However, it is a tremendous challenge to engineer all of the above characteristics into a single carrier particle. Here, we show that natural H-ferritin (HFn) nanocages can carry high doses of doxorubicin (Dox) for tumor-specific targeting and killing without any targeting ligand functionalization or property modulation. Dox-loaded HFn (HFn-Dox) specifically bound and subsequently internalized into tumor cells via interaction with overexpressed transferrin receptor 1 and released Dox in the lysosomes. In vivo in the mouse, HFn-Dox exhibited more than 10-fold higher intratumoral drug concentration than free Dox and significantly inhibited tumor growth after a single-dose injection. Importantly, HFn-Dox displayed an excellent safety profile that significantly reduced healthy organ drug exposure and improved the maximum tolerated dose by fourfold compared with free Dox. Moreover, because the HFn nanocarrier has well-defined morphology and does not need any ligand modification or property modulation it can be easily produced with high purity and yield, which are requirements for drugs used in clinical trials. Thus, these unique properties make the HFn nanocage an ideal vehicle for efficient anticancer drug delivery.

Dysregulation of Wnt signalling leads to developmental defects and diseases. Non-canonical Wnt signalling via planar cell polarity proteins regulates cell migration and convergent extension; however, the underlying mechanisms are poorly understood. Here we report that Wnt5a uses CD146 as a receptor to regulate cell migration and zebrafish embryonic convergent extension. CD146 binds to Wnt5a with the high affinity required for Wnt5a-induced activation of Dishevelled (Dvl) and c-jun amino-terminal kinase (JNK). The interaction between CD146 and Dvl2 is enhanced on Wnt5a treatment. Mutation of the Dvl2-binding region impairs its ability to activate JNK, promote cell migration and facilitate the formation of cell protrusions. Knockdown of Dvls impairs CD146-induced cell migration. Interestingly, CD146 inhibits canonical Wnt signalling by promoting β-catenin degradation. Our results suggest a model in which CD146 acts as a functional Wnt5a receptor in regulating cell migration and convergent extension, turning off the canonical Wnt signalling branch.

Using antibody phage display technique, a human single chain antibody to vascular endothelial growth factor (VEGF) has been cloned. The antibody expression reached 45% of the total bacterial proteins. The purification and refolding of the antibody were completed in one step by using gel filtration chromatograph. ELISA analysis showed that the antibody not only specifically bound to human VEGF, but also competitively inhibited VEGF reacting with its receptors. In order to raise the affinity of the single chain antibody, its heavy chain variable region was randomly mutated using error-prone PCR and an antibody mutant library was constructed, from which a mutant with higher affinity was screened out. The three-dimensional structure and binding affinity of wild type and mutant antibody were compared. Our study provided a potential reagent for tumor angiogenic therapy and a significant model for antibody high-level expression and affinity maturation.

Determining the concentration of hydrogen peroxide (H2O2) is of great importance in food, pharmaceutical, environmental and clinical analyses. Horseradish peroxidase (HRP), an enzyme specifically catalyzing the oxidative reaction of H2O2 to develop color reaction, has been widely used for measuring H2O2 concentration. However, owing to the instability and high cost of this enzyme, discovering efficient mimics of peroxidase has been important to conquer these disadvantages of protein catalyst. Recently we have found that Fe3O4 magnetic nanoparticles (Fe3O4 MNPs) possess intrinsic peroxidase-like activity, which can catalyze oxidation of various peroxidase substrates in the presence of H2O2. Based on this finding, we developed a spectrometric method using Fe3O4 MNPs as a catalyst to determine H2O2 in rainwater. Our data show that the Fe3O4 MNPs are efficient catalysts to determine H2O2 in rainwater. Compared to HRP, the Fe3O4 MNPs are reusable and economical and these characteristics make the particles a board range of applications in determining H2O2 in the rainwater.

Recently, enhanced CD146 expression was reported on endothelial cells in intestinal biopsies from patients with inflammatory bowel disease. However, the underlying mechanism remains unknown. Here, we found that overexpressed endothelial CD146 promoted the inflammatory responses in inflammatory bowel disease, which further potentiated the occurrence of colitis-associated colorectal carcinogenesis. Eliminating endothelial CD146 by conditional knockout significantly ameliorated the severity of inflammation in two different murine models of colitis, and decreased tumor incidence and tumor progression in a murine model of colitis-associated colorectal carcinogenesis. Mechanistic study showed that cytokine tumor necrosis factor-α (TNF-α) up-regulated the expression of endothelial CD146 through NF-κB transactivation. In turn, the enhanced endothelial CD146 expression promoted both angiogenesis and proinflammatory leukocyte extravasations, contributing to inflammation. Using an anti-CD146 antibody, AA98, alone or together with an anti–TNF-α antibody significantly attenuated colitis and prevented colitis-associated colorectal carcinogenesis in mice. Our study provides the first evidence that CD146 plays a dual role on endothelium, facilitating leukocyte extravasations and angiogenesis, thus promoting inflammation. This finding not only reveals the function and regulating mechanism of CD146 in inflammatory bowel disease, but also provides a promising therapeutic strategy for treating inflammatory bowel disease and preventing colitis-associated colorectal carcinogenesis.

The ability to selectively block the entry of leukocytes into the central nervous system (CNS) without compromising the immune system is an attractive therapeutic approach for treating multiple sclerosis (MS). Using endothelial CD146-deficienct mice as a MS model, we found that endothelial CD146 plays an active role in the CNS-directed extravasation of encephalitogenic T cells, including CD146(+) TH1 and TH17 lymphocytes. Moreover, treating both active and passive MS models with the anti-CD146 antibody AA98 significantly decreased the infiltrated lymphocytes in the CNS and decreased neuroinflammation. Interestingly, the ability of AA98 to inhibit the migration of CD146(+) lymphocytes was dependent on targeting endothelial CD146, but not lymphocytic CD146. These results suggest a key molecular target located on the blood-brain barrier endothelium that mediates the extravasation of inflammatory cells into the CNS. In addition, our data suggest that the AA98 is a promising candidate for treating MS and other CNS autoimmune diseases.

A novel ‘pipeline’ system for the preparation of therapeutic monoclonal antibodies (mAb) in a non-GMP compliant environment has been developed. We used sterile silica-gel pipes to connect individual process units, in order to form a fully-enclosed and seamlessly connected system. This ‘pipeline’ system was used to implement downstream preparation processes for a humanized anti-CD146 mAb, huAA98, which is a therapeutic mAb generated to inhibit cancer-related angiogenesis. The quality assessment of the huAA98 end-product indicated that endotoxin levels were 0.016 EU/ml, protein A levels were 1.08 ng/ml and host cell protein (HCP) was undetectable. Thus, all measures were below the clinical criteria set by the Chinese Pharmacopoeia (Edition 2010). Having passed our proof-of-concept test, this ‘pipeline’ system can be used as a universal platform for the preparation of mAbs suitable for pre-clinical studies, in a non-GMP compliant laboratory environment.

Cell adhesion molecules (CAMs) are crucial effectors for the development and maintenance of the nervous system. Mutations in human CAM genes are linked to brain disorders and psychological diseases, and CAM knockout mice always exhibit similar behavioral abnormalities. CD146 is a CAM of the immunoglobulin superfamily that interacts with Neurite Outgrowth Factor and involved in neurite extension in vitro. However, little is known about its in vivo function in the nervous system. In this study, we used a murine CD146 nervous system knockout (CD146(ns-ko)) model. We found that the brains of some CD146(ns-ko) mice were malformed with small olfactory bulbs. CD146(ns-ko) mice exhibited lower body weights and smaller food intake when compared with wild type littermates. Importantly, behavior tests revealed that CD146(ns-ko) mice exhibited significant decreased locomotor activity and impaired capacity for spatial learning and memory. Our results demonstrate that CD146 is important for mammalian nervous system development and proper behavior patterns.

Summary: The aim of this study is to raise tumor-suppressing monoclonal antibodies (mAbs) against colorectal carcinomas. Here, we generated a novel mAb 3P9, targeted a cancer-associated carbohydrate antigen sialyl-Tn (sTn), which showed significant inhibitory effect on proliferation and migration of sTn + cells and tumor growth by inducing apoptosis. We also demonstrated that mAb 3P9 showed higher sensitivity and specificity in immunohistochemistry assay on colonic adenocarcinoma than the broadly used commercial anti-sTn antibody B72.3. These results provide the first evidence that mAb 3P9 has potential applications, not only for diagnosis but also for antibody-based tumor therapy.

Rapid and sensitive detection methods are in urgent demand for the screening of extensively used organophosphorus pesticides and highly toxic nerve agents for their neurotoxicity. In this study, we developed a novel Fe(3)O(4) magnetic nanoparticle (MNP) peroxidase mimetic-based colorimetric method for the rapid detection of organophosphorus pesticides and nerve agents. The detection assay is composed of MNPs, acetylcholinesterase (AChE), and choline oxidase (CHO). The enzymes AChE and CHO catalyze the formation of H(2)O(2) in the presence of acetylcholine, which then activates MNPs to catalyze the oxidation of colorimetric substrates to produce a color reaction. After incubation with the organophosphorus neurotoxins, the enzymatic activity of AChE was inhibited and produced less H(2)O(2), resulting in a decreased catalytic oxidation of colorimetric substrates over MNP peroxidase mimetics, accompanied by a drop in color intensity. Three organophosphorus compounds were tested on the assay: acephate and methyl-paraoxon as representative organophosphorus pesticides and the nerve agent Sarin. The novel assay displayed substantial color change after incubation in organophosphorus neurotoxins in a concentration-dependent manner. As low as 1 nM Sarin, 10 nM methyl-paraoxon, and 5 μM acephate are easily detected by the novel assay. In conclusion, by employing the peroxidase-mimicking activity of MNPs, the developed colorimetric assay has the potential of becoming a screening tool for the rapid and sensitive assessment of the neurotoxicity of an overwhelming number of organophosphate compounds.

CD146 is a novel endothelial biomarker and plays an essential role in angiogenesis; however, its role in the molecular mechanism underlying angiogenesis remains poorly understood. In the present study, we show that CD146 interacts directly with VEGFR-2 on endothelial cells and at the molecular level and identify the structural basis of CD146 binding to VEGFR-2. In addition, we show that CD146 is required in VEGF-induced VEGFR-2 phosphorylation, AKT/p38 MAPKs/NF-κB activation, and thus promotion of endothelial cell migration and microvascular formation. Furthermore, we show that anti-CD146 AA98 or CD146 siRNA abrogates all VEGFR-2 activation induced by VEGF. An in vivo angiogenesis assay showed that VEGF-promoted microvascular formation was impaired in the endothelial conditional knockout of CD146 (CD146EC-KO). Our animal experiments demonstrated that anti-CD146 (AA98) and anti-VEGF (bevacizumab) have an additive inhibitory effect on xenografted human pancreatic and melanoma tumors. The results of the present study suggest that CD146 is a new coreceptor for VEGFR-2 and is therefore a promising target for blocking tumor-related angiogenesis.

Iron oxide magnetic nanoparticles (MNPs) are widely used as diagnostic and therapeutic agents for biomedical applications. Quantitatively analyzing biodistribution, pharmacokinetics and organ clearance of MNPs in mouse models is important for understanding their in vivo behavior. In this study, we developed a novel histochemical method for visualizing unlabeled MNPs in mouse tissues by employing their intrinsic peroxidase-mimicking activity, regarding which we reported previously that MNPs could catalyze the oxidation of peroxidase substrates to produce a color reaction at the site of MNPs (Gao et al. Nat. Nanotechnol.2007, 2, 577-583). Based on this MNPs-peroxidase approach, we determined the biodistribution and organ clearance of MNPs by visualizing and quantifying the localization of MNPs within the main organs. Compared to traditional Prussian blue assay, this novel MNPs-peroxidase approach has higher sensitivity. In conclusion, the developed MNPs-peroxidase approach based on intrinsic peroxidase activity of iron oxide nanoparticles was used effectively for quantitative detection of MNPs in mice by histochemical staining. Presumably, other nanoparticles having intrinsic peroxidase activity could also be considered.