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Fungal lectin can bind specific carbohydrate structures of the host and work in recognition and adhesion or as a toxic factor. AofleA, as a fucose-specific lectin from widely studied nematode predatory fungus Arthrobotrys oligospora, possibly plays a key role in the event of capturing nematodes, but the mechanism remains unknown. Here we report the crystal structure of AofleA, which exists as a homodimer with each subunit folds as a six-bladed β-propeller. Our structural and biological results revealed that three of the six putative binding sites of AofleA had fucose-binding abilities. In addition, we found that AofleA could bind to the pharynx and intestine of the nematode in a fucose-binding-dependent manner. Our results facilitate the understanding of the mechanism that fucose-specific lectin mediates fungi-nematodes interaction, and provide structural information for the development of potential applications of AofleA.

Lectins are the primary recognition macromolecules for various types of fucosylation, a common eukaryotic post-translational modification. In this study, we report the heterologous expression and molecular binding properties of a fucose-specific lectin, AofleA, isolated from Arthrobotrys oligospora. This is the first reported fucose-specific lectin found in nematophagous fungi. The recombinant AofleA (r-AofleA) was expressed in Escherichia coli with high efficiency, yielding at least 500 mg of soluble and functional r-AofleA per liter of broth. Using hemagglutination inhibition assay and glycan microarray analysis, r-AofleA was found to be broadly specific for fucosylated glycans or oligosaccharides including Fucα(1–2), Fucα(1–3), Fucα(1–4) and Fucα(1–6) linkages, similar to Aleuria aurantia lectin (AAL). Frontal affinity chromatography showed that r-AofleA has high affinity towards PA-L-fucose with an average Kd value of 15 nM. These findings provide a basis for improved understanding of the structure and functions of AofleA during recognition and capture of prey nematodes by nematophagous fungus A. oligospora.

Pichia kudriavzevii was one of the important aroma-producing fungi in the solid-state fermentation of Baijiu, and immobilization was an effective strategy for improving microbial performance. Herein, P. kudriavzevii cells were immobilized in a gel network that crosslinked by chitosan and sodium alginate to form sodium alginate/chitosan-P. kudriavzevii microspheres (SA/CS-PMs). Their structural characteristics and formation processes were characterized by SEM and FT-IR. The effect of synthesis conditions on the performance of microspheres were determined by single-factor experiments. Under the optimal conditions, the SA/CS-PMs could increase the amylase activity of the fermentation broth by 57.18%, the esterase activity by 66.13%, the content of ester by 67.04%, and could be reused at least three times. Further research results indicated that the content of ester could be increased significantly in Baijiu solid-state fermentation with the SA/CS-PMs. In conclusion, the SA/CS-PMs could improve the ester production ability of P. kudriavzevii by increasing the esterase activity, which was a valuable exploration of directional biosynthesis and a feasible strategy to improve solid-state fermentation quality.

Bronchial asthma (BA) is a chronic inflammatory disease of the airway. Previous research has shown that Yanghe Pingchuan granules (YPGs) exert a precise therapeutic effect on BA. In our previous work, we showed that YPGs improved inflammation of the airways in rat models of BA. Other studies have shown that the pathogenesis of BA is closely related to pyroptosis and that the TOLL-like receptor pathway plays a key role in the mediation of pyroptosis. Therefore, in the present study, we established a rat model of BA by applying the concept of pyroptosis and used the TLR4/NF-κB/NRLP3 signaling pathway as the target and YPGs as the treatment method. We evaluated the effects of YPGs on airway inflammation and pyroptosis in the model rats by HE staining, Masson’s staining, AP-PAS staining, western blotting, and real-time quantitative PCR. The results showed that Yanghe Pingchuan granules could significantly improve the inflammatory response of bronchial tissue in BA rats, reduce the content of inflammatory factors IL-1β and IL-18, and inhibit the expression of pyroptosis factor. Meanwhile, YPG can block the TLR4/NF-κB signaling pathway. These findings suggest that YPG may be an effective drug for the treatment of BA by blocking the TLR4/NF-κB signaling pathway and inhibiting pyroptosis.

In this work, a multiwalled carbon nanotubes@reduced graphene oxide nanoribbons core-shell heterostructure (MWCNT@rGONR)-modified glassy carbon electrode (MWCNT@rGONR/GCE) was employed to electrochemically detect glutathione (GSH). The morphologies and microstructures of the as-prepared MWCNT@rGONR heterostructure were examined by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy spectrum (FT-IR), respectively. The electrochemical characteristics and catalytic behaviors of the fabricated sensor for determination of GSH were systematically investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV), and amperometry (i–t). Under optimum conditions, the MWCNT@rGONR heterostructure modified electrode possesses the ability of strong electrocatalytic for GSH with high selectivity and sensitivity, fast response, wide linear range, low detection limit (39 nM) and outstanding reproducibility. Its further application for the quantification of GSH concentration in human serum samples was also demonstrated with satisfactory accuracy. These features indicate that the prepared core-shell MWCNT@rGONR heterostructure with unique electronic structure offers an excellent biosensing platform for sensitive and selective detection of glutathione.

Ethylene signaling converges on the ETHYLENE-INSENSITIVE3 (EIN3)/EIN3-like (EIL) transcription factors to regulate a wide range of developmental processes in plants. EBF1/2 (EIN3-binding F-box protein 1 and 2) negatively regulate the ethylene signaling pathway by mediating the degradation of EIN3/EIL proteins. We uncovered previously that SlEBF1 and SlEBF2 are involved in ethylene response, plant senescence, and fruit ripening in tomato. The present study reports on the identification of a novel tomato F-box gene, designated as SlEBF2-like due that its encoded protein is greater similarity to SlEBF2. The SlEBF2-like promoter region contains three ethylene-response elements (EREs). SlEBF2-like is upregulated by ethylene and downregulated by ethylene inhibitors in tomato seedlings. It is dynamically expressed in flowers during bud-to-anthesis and anthesis-to-post-anthesis transitions, and at the onset of fruit ripening, suggesting its role in these situations where ethylene is required for flower opening and fruit ripening. SlEBF2-like overexpression leaded to fruit elongation, caused ripening and color change to start from fruit bottom and expand gradually to the pedicel, and strongly delayed fruit development and ripening in tomato. Our study indicates that the novel EBF gene, SlEBF2-like, is involved in fruit development and ripening via regulating the ethylene response in tomato.

In this article, we study positive solutions to the system { A α u ( x ) = C n , α P V ∫ R n a 1 ( x - y ) ( u ( x ) - u ( y ) ) | x - y | n + α d y = f ( u ( x ) , υ ( x ) ) , B β υ ( x ) = C n , β P V ∫ R n a 2 ( x - y ) ( υ ( x ) - υ ( y ) ) | x - y | n + β d y = g ( u ( x ) , υ ( x ) ) . To reach our aim, by using the method of moving planes, we prove a narrow region principle and a {decay at infinity} by the iteration method. On the basis of these results, we conclude radial symmetry and monotonicity of positive solutions for the problems involving the weighted fractional system on an unit ball and the whole space. Furthermore, non-existence of nonnegative solutions on a half space is given.

Arabinoglactan protein (AGP)-rich nanoparticles obtained from the sticky exudates of Hedera helix (English ivy), have shown promising potential to be used in nanomedicine owing to their excellent aqueous solubility, low intrinsic viscosity, biocompatibility, and biodegradability. In this study, the feasibilities of utilizing ivy nanoparticles (INPs) as nano-carriers for delivering chemotherapeutic drugs in cancer therapy and as nano-fillers to develop novel scaffolds for tissue engineering in regenerative medicine are evaluated. Via electrostatic and hydrophobic interactions, pH-responsive nanoconjugates are formed between the INPs and the doxorubicin (DOX) with an entrapment ratio of 77.9 ± 3.9%. While the INPs show minimal cytotoxicity, the formed INP-DOX conjugates exhibit substantially stronger cytotoxic activity than free DOX against multiple cancer cell lines, suggesting a synergistic effect is established upon conjugation. The anti-cancer effects of the INP-DOX conjugates are further evaluated via in vivo xenograft assays by subcutaneously implanting DOX resistant cell line, SW620/Ad-300, into nude mice. The tumor volumes in mice treated with the INP-DOX conjugates are significantly less than those of the mice treated with free DOX. In addition, the INPs are further exploited as nano-fillers to develop fibrous scaffolds with collagen, via mimicking the porous matrix where the INPs are embedded under natural condition. Enhanced adhesion of smooth muscle cells (SMCs) and accelerated proliferation of mouse aortic SMCs are observed in this newly constructed scaffold. Overall, the results obtained from the present study suggest great potential of the INPs to be used as biocompatible nanomaterials in nanomedicine. The AGP-rich INP renders a glycoprotein architecture that is amenable for modification according to the functional designs, capable of being developed as versatile nanomaterials for extensive biomedical applications. Statement of Significance Naturally occurring organic nanomaterials have drawn increasing interest for their potential biomedical applications in recent years. In this study, a new type of naturally occurring nanoparticles obtained from the sticky exudates on the adventitious roots of English ivy ( H. helix ), was explored for its potential biomedical application. In particular, the feasibilities of utilizing ivy nanoparticles (INPs) as nano-carriers for delivering chemotherapeutic drugs in cancer therapy and as nano-fillers to develop novel scaffolds for tissue engineering in regenerative medicine were evaluated both in vitro and in vivo . Overall, the results obtained from the present study suggest the great potential of the INPs to be used as biocompatible nanomaterials in nanomedicine. This study may open a totally new frontier for exploring the biomedical application of naturally occurring nanomaterials.

Although many studies have investigated archaeal distribution in various environments, studies regarding the archaeal community structure in intertidal mudflat sediments in coastal areas are not enough. In addition, the response of archaea to bivalves bioturbation has not been reported before, nevertheless, bioturbation effects on microbes are key to many aspects of ecosystem function. In this paper, clone library construction, Restriction Fragment Length Polymorphism (RFLP) and Denaturing Gradient Gel Electrophoresis DGGE (DGGE) were used to study the archaeal community structure in two typical intertidal mudflats in Southeast coast of China: the one mainly used for aquaculture in a semi-enclosed Bay (Sansha Bay), and the other one mainly used for recreation in a developed city (Xiamen). In addition, the potential influence of sampling time and the in situ bioremediation by artificially introducing bivalve ark shell (Tegillarca granosa) to mudflat sediments on archaeal communities were also investigated. A total of 283 clones were randomly selected from four clone libraries and were divided into 42 RFLP patterns. All the cloned sequences fell into three phyla: the Thaumarchaeota (group MGI), Crenarchaeota (group MCG) and Euryarchaeota (groups MBG-D, MBG-E, VAL III and DHVE 6), in which Thaumarchaeota MGI was dominant, occupying 75.6% of total clones. Crenarchaeota MCG and Euryarchaeota accounted for 15.2% and 9.2% respectively. The archaeal diversity in Xiamen intertidal sediment was lower than that of Sansha Bay. Introducing ark shell seemed to increase archaeal diversity and the proportion of MCG and decrease the proportion of MGI in the clone library. DGGE profiles showed that most of the archaea populations were metabolically active, and the fingerprint clustering results were basically consistent with the results from clone libraries.

A carnivorous fungus, Arthrobotrys oligospora, has been shown to secrete nanoparticles. In the present work, the potential of two charge-selective fractions of fungal nanoparticles (FNPs) as bioactive nanocarriers in cancer therapy is explored by investigating their immunostimulatory activities, cytotoxic mechanisms and in vitro immunochemotherapeutic effects. A surface charge-selective fractionation procedure to purify crude FNPs has been established, and two FNP fractions (i.e. FNP1 and FNP2), with different surface charges and similarly reduced diameters of 100–200 nm, are obtained. Both FNP fractions enhance the secretion of multiple proinflammatory cytokines and chemokines from macrophages and splenocytes. However, FNP2 has stronger cytotoxicity than FNP1. It is FNP2 not FNP1 that could clearly inhibit cell proliferation by inducing apoptosis and arresting cells at the sub G0/G1 phase. Both the FNP fractions can form pH-responsive nanocomplexes with doxorubicin (DOX) via electrostatic interactions. For direct cytotoxicity, DOX–FNP2 complexes demonstrate higher activity than DOX against multiple tumor cells, while DOX–FNP1 complexes show weaker activity than DOX. Interestingly, in a co-culture experiment where splenocytes are co-cultured with tumor cells, both DOX–FNP complexes demonstrate higher cytotoxicity than DOX. In conclusion, this work proposes a combined therapeutics for cancer treatment using charge-selective fractions of FNPs as bioactive nanocarriers.

In this paper, we discuss a class of parabolic equations with variable exponents. By using the Steklov average and Young’s inequality, we establish energy estimates for solutions to these equations. Then based on measure theoretical arguments, we derive intrinsic Harnack inequalities for solutions from functions and cylinders constructed here.

A mixed Pluronic micelle for delivery of paclitaxel (PTX) with Pluronic P105 and L101 was capable of sensitizing resistant SKOV-3/PTX tumor cells. A significant inhibition of P-gp efflux system was observed in the range of monomer or micelle concentrations of the mixed Pluronics in the resistant tumor cells. Importantly, the mixed micellar PTX also showed enhanced apoptotic effect, and drastically changed the pharmacogenomic responses to free PTX. It was found that some important genes for apoptosis induction, such as BCL-2 antagonist and death domain receptor, displayed elevated levels; some cell cycle-arresting genes, such as cyclins, cyclin-dependent kinase regulator, cullin and forhead box M, showed significant down-regulated levels; and some clinical prognostic genes for resistance to chemotherapy and metabolism, such as drug efflux pump and cytochrome P450, were also down-regulated. It is concluded that inhibition of P-gp efflux system, enhanced induction of apoptosis, and significant changes of expression profiles of apoptosis, resistance and cell cycle arresting-related genes were responsible for PTX-resistance reversal by the mixed Pluronic P105/L101 micelles in the SKOV-3/PTX tumor cells.

In this paper, we prove that local weak solutions for doubly degenerate parabolic systems with singular weights are locally bounded.

Three poly(caprolactone)-modified Pluronic P105 polymers (P105/PCLs) were synthesized using commercially available ε-caprolactone monomers and Pluronic P105 copolymers. The chemical structures, compositions and molecular weights of the P105/PCLs were confirmed by FT-IR, (1)H NMR and GPC measurements. Three paclitaxel (PTX)-loaded P105/PCL polymeric micelles were then prepared, and they showed average diameters in the range of 30-150 nm, drug-loading coefficients of 0.15%-5.43%, and encapsulation ratios of 2.1%-76.53%. The in vitro cytotoxicity assay demonstrated that three PTX-loaded P105/PCL micelles were able to sensitize the resistant SKOV-3/PTX tumor cells. The PTX-loaded P105/PCL(50) micelle was then selected for an in vivo antitumor efficacy study. The tumor volumes in nude mice bearing s.c. resistant SKOV-3/PTX carcinoma treated with this micellar PTX were significantly less than the control group treated with Taxol. It was demonstrated that three PCL-modified P105 monomers and micelles inhibited P-gP efflux activity in the resistant SKOV-3/PTX cells via at least three intracellular events: 1) inhibition of ATPase of P-gP, 2) decrease of membrane microviscosity and 3) a loss of mitochondrial membrane potential and subsequent decrease of ATP levels at the concentration of monomers (0.001%) and/or micelles (0.01-1.0%). Considering other favorable characteristics, such as sustained PTX release in vitro, long-circulating time in vivo and increased PTX concentration in the tissues of ovaries and uterus in mice, the PCL-modified Pluronic P105 polymeric micelle system could have important clinical implications for delivery of paclitaxel and treatment of the resistant ovarian tumors.

A self-assembled micelle drug delivery system was constructed with an oxidized phospholipid for anthracycline anti-cancer drug delivery. An oxidized phospholipid, 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazPC), was chosen to fabricate micelles via both electrostatic and hydrophobic interactions for delivery of doxorubicin (DOX) and idarubicin (IDA). The formation of ion–pair complexes between PazPC and DOX was first investigated under different pH conditions. Drug-loaded PazPC micelles at a 5:1 molar ratio of lipid/drug at pH 7.0 were then prepared by the solvent evaporation method. The empty and drug-loaded PazPC micelles exhibited a small particle size (∼10 nm) and high encapsulation efficiency. In vitro stability and release profile indicated that the micelles were stable at physiological conditions, but exhibited pH-sensitive behavior with accelerated release of DOX or IDA in an acidic endosome environment. Finally, in vitro uptake and cytotoxicity were evaluated for leukemia P388 and its resistant subline P388/ADR. The drug-loaded PazPC micelles enhanced drug uptake and exhibited higher cytotoxicity in both leukemia cells in comparison to free drugs. In conclusion, we developed a novel pH sensitive oxidized phospholipid-based micellar formulation which could potentially be useful in delivering anthracycline anti-cancer drugs and provide a novel strategy for increasing the therapeutic index while overcoming multidrug resistance for leukemia treatment.

In this paper, based on measure theoretical arguments, we establish Harnack estimates and Holder continuity of nonnegative weak solutions for a degenerate parabolic equation with a singular weight. We transform the equation by performing the change of function. The energy estimates, the upper boundedness, the lower boundedness and the expansion of positivity for the solutions to the transformed equation are obtained. Then our aim is reached.

Deposited with different oxygen partial pressures and substrate temperatures, MgxZn1−xO thin films were prepared using a Mg0.6Zn0.4O ceramic target by magnetron sputtering. The structural and optical properties of the prepared thin films were investigated. The X-ray diffraction spectra reveal that all the films on quartz substrate are grown along (2 0 0) orientation with cubic structure. The lattice constant decreases and the crystallite size increases with the increase of substrate temperature. Both energy dispersive X-ray spectroscopy and calculated results suggest the ratio of Mg/Zn increases with increasing substrate temperature. The thin film deposited with Ts = 500 °C has a minimal rms roughness of 7.37 nm. The transmittance of all the films is higher than 85% in the visual region. The optical band gap is not sensitive to the oxygen partial pressure, while it increases from 5.63 eV for Ts = 100 °C to 5.95 eV for Ts = 700 °C. In addition, the refractive indices calculated from transmission spectra are sensitive to the substrate temperature. The photoluminescence spectra of MgxZn1−xO thin films excited by 330 nm ultraviolet light indicate that the peak intensity of the spectra is influenced by the oxygen partial pressure and substrate temperature.

In this paper, we consider nonnegative weak solutions for a class of degenerate parabolic equations. Using Moser’s method, we get the local boundedness of solutions to equations of this class. Then we prove that the solutions are locally Holder continuous.

In this paper, we give the complete descriptions for the PS-sequences of the energy functionals associated with the singular quasilinear elliptic problems involving critical Sobolev exponents on a bounded smooth domain invariant under the action of a group of orthogonal transformations and the whole space, respectively. As applications, we prove the existence of positive and nodal solutions for the singular quasilinear elliptic problem involving critical Sobolev exponents.

A novel visible light (VL) active photocatalyst (TiO 2 /D-PVA) was prepared in one portion of polyvinyl alcohol (PVA) and Ti(OH) 4 by means of hydrothermal method, and the relationship between the prepared conditions and VL photocatalytic activity was investigated. The synthesized photocatalyst was characterized by XRD, UV–vis, XPS, FTIR and EPR. The results show that PVA was dehydrated to produce conjugated unsaturated D-PVA. The VL photocatalytic activity was attributed to the interaction between D-PVA and TiO 2 . The TiO 2 /D-PVA, synthesized with the 1:10 feed ratio of PVA to TiO 2 at 180 °C, exhibited a significant VL activity for the Methyl orange (MO) degradation. The degradation rate fit the characteristic of apparent first-order kinetics. The mechanism of MO degradation was also proposed.

A novel nonviral gene transfer vector was developed by modifying nanostructured lipid carrier (NLC) with cetylated polyethylenimine (PEI). Polycation nanostructured lipid carrier (PNLC) was prepared using the emulsion-solvent evaporation method. Its in vitro gene transfer properties were evaluated in the human lung adenocarcinoma cell line SPC-A1 and Chinese Hamster Ovary (CHO) cells. Enhanced transfection efficiency of PNLC was observed after the addition of triolein to the PNLC formulation and the transfection efficiency of the optimized PNLC was comparable to that of Lipofectamine 2000. In the presence of 10% serum the transfection efficiency of the optimal PNLC was not significantly changed in either cell line, whereas that of Lipofectamine 2000 was greatly decreased in both. Thus, PNLC is an effective nonviral gene transfer vector and the gene delivery activity of PNLC was enhanced after triolein was included into the PNLC formulation.

Designing biomaterial scaffolds remains a major challenge in tissue engineering. Key to this challenge is improved understanding of the relationships between the scaffold properties and its degradation kinetics, as well as the cell interactions and the promotion of new matrix deposition. Here we present the use of non-linear spectroscopic imaging as a non-invasive method to characterize not only morphological, but also structural aspects of silkworm silk fibroin-based biomaterials, relying entirely on endogenous optical contrast. We demonstrate that two photon excited fluorescence and second harmonic generation are sensitive to the hydration, overall beta sheet content and molecular orientation of the sample. Thus, the functional content and high resolution afforded by these non-invasive approaches offer promise for identifying important connections between biomaterial design and functional engineered tissue development. The strategies described also have broader implications for understanding and tracking the remodeling of degradable biomaterials under dynamic conditions both in vitro and in vivo.

Knowledge of the natural course after an ST-elevation myocardial infarction (STEMI) treated according to guidelines is limited because comprehensive serial magnetic resonance imaging (MRI) of systolic left ventricular function, edema, perfusion, and infarct size after STEMI has not been undertaken. The aim of this study was to evaluate effects of therapy for STEMI on left ventricular function and perfusion and to test the hypothesis that myocardial perfusion by MRI predicts recovery of left ventricular function.Cine MRI, edema, first-pass perfusion, and late enhancement imaging were performed in 58 patients at day 2 and at 1 and 6 months after successful primary percutaneous coronary stent intervention for STEMI.Ejection fraction increased 6.3% during the first month (P.001) and 1.9% from 1 to 6 months (P.06), indicating a maximal recovery very early after the infarction. The systolic wall thickening in the infarct area almost doubled (P.001), the perfusion of infarcted myocardium increased approximately 50% (P = .02), and perfusion improved in 72% of patients. Edema decreased with a mean of 2 segments (P.001) during the first month and another 2.5 segments from 1 to 6 months (P.001). Infarct size decreased to 1 month (P = .01) and was unchanged from 1 to 6 months (P = .5). Baseline perfusion did not predict improvement in ejection fraction (r = 0.2, P = .2) but did predict regional systolic function (P = .03).Left ventricular function, perfusion, and infarct mass recovered substantially after STEMI, with the main part of the change within the first month. First-pass perfusion at rest appeared to predict regional ventricular recovery.

Objective The influence of treatment with granulocyte-colony stimulating factor (G-CSF) on the development of in-stent intimal hyperplasia is not known. We aimed to study this phenomenon in patients who had stents implanted in the course of an acute ST-elevation infarction and successively were treated with G-CSF. Method We performed angiography and intracoronary ultrasound follow-up after 5 months in 41 consecutive patients in the STEMMI trial, which is a randomized double-blind placebo-controlled study on the effect of G-CSF injections on the myocardial function following acute myocardial infarction in patients treated with primary percutaneous coronary stent implantation. The intracoronary ultrasound images were analyzed by a blinded and independent core laboratory. Results There were no differences in in-stent neo-intimal hyperplasia determined by intracoronary ultrasound between patients treated with G-CSF compared to patients treated with placebo. Neo-intimal hyperplasia per mm of stent was 1.87 (±1.41) and 1.89 (±1.39), respectively ( p =0.97). Angiographic in-segment restenosis (>50% diameter stenosis) was found in 28% of patients (24% in the G-CSF group and 33% in the placebo group; p =0.55). Conclusion G-CSF treatment following coronary stent implantation in primary PCI treated AMI patients does not increase in-stent restenosis excessively and it does not seem warranted to limit further study of effects of G-CSF for that reason.

In human body ascorbic acid plays an essential role in the synthesis and function of skeletal tissues and immune system factors. Ascorbic acid is also a major physiological antioxidant, repairing oxidatively damaged biomolecules, preventing the formation of excessive reactive oxygen species or scavenging these species. We recently reported the synthesis of ascorbic acid-functionalized polymers in which the antioxidant features of the pendant ascorbic acid groups was preserved. In the present work we demonstrate that ascorbic acid-functionalized poly(methyl methacrylate) (AA-PMMA) can modulate the proliferation and osteogenic differentiation of early and late-passage bone marrow-derived human mesenchymal stem cells (MSCs). The covalently coupled ascorbic acid impacted MSCs differently than when ascorbic acid was presented to the cells in soluble form. At optimal concentration, the covalently coupled ascorbic acid and soluble ascorbic acid synergistically promoted and retained the ability of MSCs to respond to osteogenic stimulation over extensive cell expansions in vitro. In the presence of soluble ascorbic acid, AA-PMMA films prepared at optimal concentrations (0.1 mg/ml in the present study) showed a significant promotive effect over other concentrations and tissue culture plastic (TCP) with respect to osteogenic differentiation of both EP (young) and LP (old) MSCs. These results suggest that the coupled ascorbic acid is acting mainly at the extracellular level and, at optimal concentrations, the immobilized extracellular ascorbic acid and soluble ascorbic acid synergistically promote osteogenic differentiation of MSCs. Importantly, the covalently coupled ascorbic acid on the films of optimal concentration was able to preserve the capacity of MSCs to undergo osteogenic differentiation in vitro. These results suggest an important role for functionalized biomaterials with antioxidant features in control of cell physiology and cell aging phenomena.

Adult cartilage tissue has limited self-repair capacity, especially in the case of severe damages caused by developmental abnormalities, trauma, or aging-related degeneration like osteoarthritis. Adult mesenchymal stem cells (MSCs) have the potential to differentiate into cells of different lineages including bone, cartilage, and fat. In vitro cartilage tissue engineering using autologous MSCs and three-dimensional (3-D) porous scaffolds has the potential for the successful repair of severe cartilage damage. Ideally, scaffolds designed for cartilage tissue engineering should have optimal structural and mechanical properties, excellent biocompatibility, controlled degradation rate, and good handling characteristics. In the present work, a novel, highly porous silk scaffold was developed by an aqueous process according to these criteria and subsequently combined with MSCs for in vitro cartilage tissue engineering. Chondrogenesis of MSCs in the silk scaffold was evident by real-time RT-PCR analysis for cartilage-specific ECM gene markers, histological and immunohistochemical evaluations of cartilage-specific ECM components. Dexamethasone and TGF-beta3 were essential for the survival, proliferation and chondrogenesis of MSCs in the silk scaffolds. The attachment, proliferation, and differentiation of MSCs in the silk scaffold showed unique characteristics. After 3 weeks of cultivation, the spatial cell arrangement and the collagen type-II distribution in the MSCs-silk scaffold constructs resembles those in native articular cartilage tissue, suggesting promise for these novel 3-D degradable silk-based scaffolds in MSC-based cartilage repair. Further in vivo evaluation is necessary to fully recognize the clinical relevance of these observations.

A significant need exists for long-term degradable biomaterials which can slowly and predictably transfer a load-bearing burden to developing biological tissue. In this study Bombyx mori silk fibroin yarns were incubated in 1mg/ml Protease XIV at 37 degrees C to create an in vitro model system of proteolytic degradation. Samples were harvested at designated time points up to 12 weeks and (1) prepared for scanning electron microscopy (SEM), (2) lyophilized and weighed, (3) mechanical properties determined using a servohydraulic Instron 8511, (4) dissolved and run on a SDS-PAGE gel, and (5) characterized with Fourier transform infrared spectroscopy. Control samples were incubated in phosphate-buffered saline. Fibroin was shown to proteolytically degrade with predictable rates of change in fibroin diameter, failure strength, cycles to failure, and mass. SEM indicated increasing fragmentation of individual fibroin filaments from protease-digested samples with time of exposure to the enzyme; particulate debris was present within 7 days of incubation. Gel electrophoresis indicated a decreasing amount of the silk 25 kDa light chain and a shift in the molecular weight of the heavy chain with increasing incubation time in protease. Results support that silk is a mechanically robust biomaterial with predictable long-term degradation characteristics.

Objectives A phase I safety and efficacy study with granulocyte colony stimulating factor (G-CSF) mobilization of bone marrow stem cells to induce vasculogenesis in patients with severe ischemic heart disease (IHD) was conducted. Design, patients and results 29 patients with IHD participated in the study. Thirteen patients were treated with G-CSF for 6 days and 16 patients served as controls. G-CSF treatment was without any serious adverse events. Four patients were "poor mobilizers" with a maximal increase in CD34+ cells to 5,000±700/mL blood (mean±S.D.) compared to 28,900±5,100/mL blood in "mobilizers". At the follow-up, G-CSF treated had improved in CCS classification, NTG consumption and angina attacks, but the controls only in CCS classification. No difference was seen between the two groups. The decline in NTG consumption tended to be significant in "mobilizers" compared to controls. Myocardial perfusion was unchanged at adenosine stress single photon emission computerized tomography (SPECT) or magnetic resonance images (MRI). Left ventricular ejection fraction decreased from 57% to 52% ( p p =0.07, SPECT) in G-CSF treated, but was unchanged measured with echocardiography. Conclusions Treatment by G-CSF improved symptoms but not signs of myocardial ischemia in patients with severe IHD. The effects seemed related to mobilization of stem cells. An adverse effect on ejection fraction could not be excluded.

For magnetic materials with exchange interaction, A=A1+A2 (A1>0, A2 |A2|, there is the coexistence of FM and SG; when |A2|>A1, there is the coexistence of AFM and SG. The phase diagram has been derived based on the ratio of A1/|A2| for the ferromagnetism, antiferromagnetism and spin glass.

Sperm quality of the sea urchin, Anthocidaris crassispina, after exposure to environmentally realistic UV-B irradiances, was assessed by changes in sperm motility (measured by the computer-assisted sperm analysis (CASA) system), and related to subsequent fertilization success. Percentage motile sperm of A. crassispina declined significantly after exposure to a UV-B dose of 16.2 kJ m(-2), while sperm motion velocity as measured by curvilinear velocity (VCL), straight line velocity (VSL), and average path velocity (VAP) showed significant reduction after exposure to a UV-B dose of 5.4 kJ m(-2). A parallel study showed that fertilization success was significantly reduced after sperm were exposed to UV-B doses > or = 5.4 kJ m(-2). Notably, the four sperm motility parameters were strongly correlated with fertilization success (P < 0.001), followed the increasing order: VSL (r = 0.8) < % motile sperm (r = 0.804) < VCL (r = 0.912) < VAP (r = 0.928). Fertilization success is best predicted by VAP using the exponential model: y = 8.678 + 90.202/[1 + exp(82.83 - x)/10.27)] (r(2) = 0.95). Thus, impairment of sperm motility of sea urchin, as measured by the CASA method, can be used to predict reproductive success and ecological effects.

II–VI wide band-gap semiconductor ternary Mg x Zn 1− x O nanocrystalline films have been successfully formed on conductive glass from ZnO powder by electrophoresis deposition (EDP). In comparison with ZnO powder, the Mg x Zn 1− x O films presented a more preferential crystalline orientation. Room temperature (RT) PL spectra of Mg x Zn 1− x O films revealed a stronger band-edge ultraviolet (UV) emission and a narrower FWMH of 13 nm than that of ZnO powder. The UV emission peak of Mg x Zn 1− x O film is located at the range of 375–381 nm with a small blue shift from that of ZnO powder. In addition, the ratio of PL peak intensity of band-edge emission to the deep-level emission in Mg x Zn 1− x O films reached as high as 135:1 while compared with 23:1 of ZnO powder under the same He–Cd laser excitation level. Consequently, these electrophoretic deposition (EPD) Mg x Zn 1− x O films exhibited a good quality for excitonic emission at RT.

Experimental results of thermoelectric power (TEP) measurements in MgB 2 from 80 to 320 K are presented. The TEP is positive and about 7.6 μV/K at room temperature. It varies with temperature linearly in temperature regions below 190 K and above 240 K, but with different slope. The results imply a multiple band contribution to the transport properties.