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The carbon forms made from sucrose and microcapsules have successfully fabricated using gel-casting method. The structure, density, compressive strength and thermal conductivity were characterized. Carbon foams have porous structure of open cells and closed cells. The density of carbon foams is regulated in the range of 0.29-0.65 g/cm3, whereas the compressive strength is in the range of 1.03-20.25 MPa. The thermal conductivity at room temperature of carbon foams can be as low as 0.11 W/m·K. Therefore, these carbon foams have potential for use as the thermal insulator. [ABSTRACT FROM AUTHOR]

The hollow spherical nano-TiO2 was successfully synthesized by carbon spheres as the template and Ti-bearing blast furnace slag as the Ti source. The SEM and TEM results showed that the as-synthesized TiO2 consist of uniform separated hollow spheres, and the sphere wall was composed of nanoparticles. The XRD result showed that the crystallized phase was rutile. Almost complete extraction of Ti from slag was achieved in NaOH-NaF molten salt. The kinetic analysis indicated that the slag decomposition was applied to control of chemical reaction of the reactionless core-shrinking model, and the apparent activation energy was39.54 kJ mol-1. [ABSTRACT FROM AUTHOR]

Using stainless steel slag and iron tailings as main raw materials, the CaO-MgO-Al2O3-SiO2 (CMAS) glass-ceramics with a solid waste utilization rate exceeding 70 % was prepared, and the effects of Cr2O3 content on the nucleation and crystallization of glass-ceramics were investigated by X-Ray diffraction (XRD). Research indicates that the main crystalline phases of CMAS are all pyroxene, and the content of Cr2O3 increases in a certain range, which promote the crystallization ability of crystals in glass. Besides, the increase of Cr2O3 content within a certain rangepromotes the crystal crystallization in glass. [ABSTRACT FROM AUTHOR]

Based on the invention and widely application of the Czochralski pulling method, vanadate crystals have been grown and commercialized in recent decades. In this paper, the growth and characterization of a series of neodymium doped vanadate crystals have been reviewed, including Nd:YVO4, Nd:GdVO4, and Nd:LuVO4. The excellent thermal-mechanical and laser property make them to be used in many respects. [ABSTRACT FROM AUTHOR]

Hollow spheres structures of La0,7Sr0,2Ca0,1Co0,9Fe0,1O3-d (LSCCT) have been synthesized via hydrothermal method using carbon spheres as template. The structure and electrical conductivity of obtained samples are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and direct current (DC) four-probe method respectively. The results show that hollow spheres structures of LSCCT with the mean particle size of 0,9 - 1,2 µm is single perovskite. The electrical conductivity of the samples is higher than 100 S/ cm from 600 to 800 °C and can meet the demand of the electrical properties for the cathode materials. [ABSTRACT FROM AUTHOR]

The titanium dioxide(TiO2) was prepared by efficient decomposition of titanium- bearing blast furnace slag (TBBFS) in molten salt system. The as-prepared TiO2 were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Almost complete leaching of Ti was achieved when TBBFS was carried out at 500 °C for about 3 h with NaOH/TBBFS mass ratio of 3:1 and NaOH to NaF molar ratio of 3:1. The XRD pattern showed that the containing titanium product obtained under optimal conditions was Na2 TiO3. The average size of the rutile TiO2 obtained was about 1.0μm and the content was up to 99,23 %. [ABSTRACT FROM AUTHOR]

Our purpose was to determine whether numbers of CD4+CD25+ T [T regulatory (Treg)] cells and mRNA expression of functional molecules of Treg are related to airway allergy and disease severity in 51 paediatric patients with allergic rhinitis or bronchial asthma and 47 healthy controls. Surface markers were evaluated with flow cytometry, and mRNA was determined with real-time polymerase chain reaction. Children with allergic disease had fewer CD4+CD25+ T cells (8·49% ± 2·41% versus 9·58% ± 2·43%, P < 0·05) and CD4+CD25hi T cells (1·32% ± 0·68% versus 1·70% ± 0·68%, P < 0·01) than control subjects. Numbers of CD4+CD25+ and CD4+CD25hi T lymphocytes were higher in children with persistent allergic rhinitis and/or moderate–severe bronchial asthma than in those with respective milder disease. The number of Treg cells was correlated positively with total immunoglobulin E level. The mRNA expression of forkhead box P3 (FoxP3) was increased in moderate–severe versus mild asthma (2·93 ± 0·38 versus 1·60 ± 0·31, P < 0·01). Patients with moderate–severe bronchial asthma also had increased mRNA expression of interleukin (IL)-10 compared with patients with mild asthma (15·24 ± 4·07 versus 3·77 ± 2·18, P < 0·01). The suppressive function of Treg cells from patients with more severe asthma was competent in vitro. On average, decreased numbers of Treg cells in children with allergic airway disease might represent a defect of the Treg population. With increased expression of FoxP3 and IL-10 in Treg from patients with relatively severe allergic disease, adaptive and functional Treg might be generated in response to aggravated atopy and disease severity. [ABSTRACT FROM AUTHOR]

Dentin bonding is a dynamic process that involves the penetration of adhesive resin monomers into the extrafibrillar and intrafibrillar demineralized collagen matrix using a wet-bonding technique. However, adhesive resin monomers lack the capacity to infiltrate the intrafibrillar space, and the excess water that is introduced by the wet-bonding technique remains at the bonding interface. This imperfectly bonded interface is inclined to hydrolytic degradation, severely jeopardizing the longevity of bonded clinical restorations. The present study introduces a dentin bonding scheme based on a dry-bonding technique, combined with the use of extrafibrillar demineralization and a collagen-reactive monomer (CRM)-based adhesive (CBA). Selective extrafibrillar demineralization was achieved using 1-wt% high-molecular weight (MW) carboxymethyl chitosan (CMCS) within a clinically acceptable timeframe to create a less aggressive bonding substance for dentin bonding due to its selectively extrafibrillar demineralization capacity. CMCS demineralization decreased the activation of in situ collagenase, improved the shrinking resistance of demineralized collagen, and thus provided stronger and more durable bonding than traditional phosphoric acid etching. The new dentin bonding scheme that contained CMCS and CBA and used a dry-bonding technique achieved an encouraging dentin bonding strength and durability with low technical sensitivity. This bonding scheme can be used to improve the stability of the resin-dentin interface and foster the longevity of bonded clinical restorations., Competing Interests: The authors declare no competing interest., (© 2021 The Authors.)

Background: Bone metastases occur frequently in patients with advanced cancer and are a serious complication of cancer. The decision to treat is often individualized, based on each patient's clinical presentation, life expectancy, and quality of life., Methods: We reviewed the current literature pertaining to management of metastatic disease to bone, and the medical, radiotherapeutic, and surgical treatment options for management of bone metastasis are discussed., Results: Current management of skeletal metastasis includes analgesia, systemic therapy, radiation therapy, and surgery. We propose treatment algorithms for management of vertebral and nonvertebral bone metastases and suggest individualized interventions based on clinical presentation., Conclusions: Management of bone metastases is complex and requires a multidisciplinary approach. The goal of treatment is often palliative, and intervention and treatment regimens should be individualized based on the specific clinical presentation of each patient.

Background: Radiation therapy is a common and effective treatment modality in the management of skeletal metastases. Recent advances in technology permitting delivery of an ablative radiation dose with an image-guided stereotactic approach improve the therapeutic threshold., Methods: The authors reviewed the literature on conventional external-beam radiation therapy and summarized the emerging data about image-guided stereotactic body radiation therapy (SBRT) for vertebral oligometastasis., Results: Pain control can be achieved effectively with conventional external-beam radiation therapy and may be further improved with image-guided spinal SBRT. Image-guided SBRT allows delivery of an ablative radiation dose with minimal toxicity, may potentially improve local tumor control, and may enhance clinical outcomes for histologies that are considered radioresistant. However, further understanding of long-term normal tissue toxicity is lacking., Conclusions: Radiotherapy options are expanding for patients with skeletal metastases. Image-guided spinal SBRT can deliver a safe ablative radiation dose to improve pain control and potentially local tumor control. Randomized clinical trials are ongoing to assess clinical benefits and outcome with spinal SBRT.

EphB2 is a receptor tyrosine kinase of the Eph family and ephrin-B1 is one of its transmembrane ligands. In the embryo, EphB2 and ephrin-B1 participate in neuronal axon guidance, neural crest cell migration, the formation of blood vessels, and the development of facial structures and the inner ear. Interestingly, EphB2 and ephrin-B1 can both signal through their cytoplasmic domains and become tyrosine-phosphorylated when bound to each other. Tyrosine phosphorylation regulates EphB2 signaling and likely also ephrin-B1 signaling. Embryonic retina is a tissue that highly expresses both ephrin-B1 and EphB2. Although the expression patterns of EphB2 and ephrin-B1 in the retina are different, they partially overlap, and both proteins are substantially tyrosine-phosphorylated. To understand the role of ephrin-B1 phosphorylation, we have identified three tyrosines of ephrin-B1 as in vivo phosphorylation sites in transfected 293 cells stimulated with soluble EphB2 by using mass spectrometry and site-directed mutagenesis. These tyrosines are also physiologically phosphorylated in the embryonic retina, although the extent of phosphorylation at each site may differ. Furthermore, many of the tyrosines of EphB2 previously identified as phosphorylation sites in 293 cells (Kalo, M. S., and Pasquale, E. B. (1999) Biochemistry 38, 14396-14408) are also phosphorylated in retinal tissue. Our data underline the complexity of ephrin-Eph bidirectional signaling by implicating many tyrosine phosphorylation sites of the ligand-receptor complex.

The Eph family of receptor tyrosine kinases and the Abl family of non-receptor tyrosine kinases have both been implicated in tissue morphogenesis. They regulate the organization of the actin cytoskeleton in the developing nervous system and participate in signaling pathways involved in axon growth. Both Eph receptors and Abl are localized in the neuronal growth cone, suggesting that they play a role in axon pathfinding. Two-hybrid screens identified regions of Abl and Arg that bind to the EphB2 and EphA4 receptors, suggesting a novel signaling connection involving the two kinase families. The association of full-length Abl and Arg with EphB2 was confirmed by co-immunoprecipitation and found to involve several distinct protein interactions. The SH2 domains of Abl and Arg bind to tyrosine-phosphorylated motifs in the juxtamembrane region of EphB2. A second, phosphorylation-independent interaction with EphB2 involves non-conserved sequences in the C-terminal tails of Abl and Arg. A third interaction between Abl and EphB2 is probably mediated by an intermediary protein because it requires tyrosine phosphorylation of EphB2, but not the binding sites for the Abl SH2 domain. The connection between EphB2 and Abl/Arg appears to be reciprocal. Activated EphB2 causes tyrosine phosphorylation of Abl and Arg, and vice versa. Interestingly, treatment of COS cells and B35 neuronal-like cells with ephrin-B1 to activate endogenous EphB2 decreased the kinase activity of endogenous Abl. These data are consistent with the opposite effects that Eph receptors and Abl have on neurite ougrowth and suggest that Eph receptors and Abl family kinases have shared signaling activities.

Semaphorins comprise a large family of phylogenetically conserved secreted and transmembrane glycoproteins, many of which have been implicated in repulsive axon guidance events. The transmembrane semaphorin Sema-1a in Drosophila is expressed on motor axons and is required for the generation of neuromuscular connectivity. Sema-1a can function as an axonal repellent and mediates motor axon defasciculation. Here, by manipulating the levels of Sema-1a and the cell adhesion molecules fasciclin II (Fas II) and connectin (Conn) on motor axons, we provide further evidence that Sema-1a mediates axonal defasciculation events by acting as an axonally localized repellent and that correct motor axon guidance results from a balance between attractive and repulsive guidance cues expressed on motor neurons.

The enteric peptides, guanylin and uroguanylin, are local regulators of intestinal secretion by activation of receptor-guanylate cyclase (R-GC) signaling molecules that produce cyclic GMP (cGMP) and stimulate the cystic fibrosis transmembrane conductance regulator-dependent secretion of Cl- and HCO3-. Our experiments demonstrate that mRNA transcripts for guanylin and uroguanylin are markedly reduced in colon polyps and adenocarcinomas. In contrast, a specific uroguanylin-R-GC, R-GCC, is expressed in polyps and adenocarcinomas at levels comparable with normal colon mucosa. Activation of R-GCC by uroguanylin in vitro inhibits the proliferation of T84 colon cells and elicits profound apoptosis in human colon cancer cells, T84. Therefore, down-regulation of gene expression and loss of the peptides may interfere with renewal and/or removal of the epithelial cells resulting in the formation of polyps, which can progress to malignant cancers of the colon and rectum. Oral replacement therapy with human uroguanylin was used to evaluate its effects on the formation of intestinal polyps in the Min/+ mouse model for colorectal cancer. Uroguanylin significantly reduces the number of polyps found in the intestine of Min/+ mice by approximately 50% of control. Our findings suggest that uroguanylin and guanylin regulate the turnover of epithelial cells within the intestinal mucosa via activation of a cGMP signaling mechanism that elicits apoptosis of target enterocytes. The intestinal R-GC signaling molecules for guanylin regulatory peptides are promising targets for prevention and/or therapeutic treatment of intestinal polyps and cancers by oral administration of human uroguanylin.

Background: Hyperhomocysteinemia has been associated with coronary atherosclerosis in many, but not all, prospective and retrospective studies. Some on these inconsistencies may be attributed to methodological variabilities., Methods: In the present study, three newly commercially available assays and one in-house HPLC assay for total homocysteine (tHcy) were utilized in 99 subjects with angiographically documented atherosclerosis and in 91 community controls matched by age, gender, and smoking history. The in-house assay, a modified Fortin and Genest HPLC method, was compared with the Bio-Rad HPLC assay, the Abbott IMx((R)) fluorescence polarization immunoassay, and a Bio-Rad enzyme-linked immunoassay (EIA) microtiter method., Results: Correlation coefficient values between the in-house HPLC assay and the Bio-Rad HPLC, the Abbott IMx, and the Bio-Rad EIA assays were 0.95, 0.96 and 0.90, respectively. Although tHcy concentrations were higher in cases compared with controls by all four methods, the difference reached statistical significance only with the in-house HPLC procedure (median, 13.5 +/- 6.7 micromol/L in cases vs 10.9 +/- 4.8 micromol/L in controls; P <0. 01, adjusting for covariates), where it was an independent predictor of case or control status, along with hypertension, total cholesterol, and triglycerides. The tHcy distributions in cases and controls demonstrated significant overlap. The number of atherosclerotic major coronary vessels was associated with significantly higher tHcy (P <0.01 for trend) in all four methods., Conclusions: The three commercial assays for tHcy differed in analytical and clinical performance. Analytically, the Abbott IMx method showed the best comparability with the in-house assay, but clinically, the three commercial methods were similar and did not distinguish cases from controls.

Exercise is associated with changes in lipids that may protect against coronary heart disease (CHD). In this study of 28 triathletes, we analyzed acute changes in serum lipid and lipoprotein concentrations after completion of the 1995 World Championship Hawaii Ironman Triathlon. With standard laboratory assays, we demonstrate significant decreases in total cholesterol, VLDL cholesterol, ApoB100, and Lp(a). Total HDL cholesterol increased significantly immediately after the race. With a novel proton NMR spectroscopy assay, we demonstrate that smaller diameter LDL particles, corresponding to small, dense LDL, declined by 62%. Moreover, larger HDL subclasses, whose levels are inversely associated with CHD, increased significantly by 11%. Smaller HDL subclasses, which have been directly associated with CHD in some studies, acutely decreased by 16%. Therefore, exercise not only acutely induces changes in lipoprotein concentrations among the standard species in a manner that favorably affects CHD risk, but also induces favorable changes in specific lipoprotein subclass size distribution that also may alter CHD risk independently of the total lipoprotein serum concentration.

The semaphorins comprise a large family of conserved glycoproteins, several members of which have been shown to function in repulsive neuronal growth cone guidance. We show here that Drosophila Semaphorin I (Sema I), a transmembrane semaphorin expressed on embryonic motor and CNS axons, is required for correct guidance of motor axons and for the formation of CNS pathways. In mutant embryos lacking Sema I, motor axons stall and fail to defasciculate at specific choice points where normally they would project to their muscle targets. In addition, a specific CNS fascicle fails to form correctly in these embryos. Rescue and ectopic expression experiments show that Sema I is required in neurons to mediate axon guidance decisions. These studies further suggest that like secreted semaphorins, transmembrane semaphorins can function as repulsive guidance cues for specific axon guidance events during neurodevelopment.