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Abstract  The interaction between two (1+1)-dimensional dipole solitons in a weak modulation lattice is studied numerically. Two unstable dipole solitons can form the bound state, and their propagation can be stabilized due to their mutual interaction. The propagation patterns with the interaction are dependent on the interval, relative phase, and input energy of the two dipole solitons. The two poles of the dipole soliton exchanges their energy after the interaction. Under the proper conditions, the interaction force between the two dipole solitons exhibits some properties similar to those between two molecules. [ABSTRACT FROM AUTHOR]

The goal of this study was to implement and validate a noninvasive, quantitative ultrasonic technique for accurate and reproducible measurement of normal-tissue toxicity in radiation therapy. The authors adapted an existing ultrasonic tissue characterization (UTC) technique that used a calibrated 1D spectrum based on region-of-interest analysis. They modified the calibration procedure by using a reference phantom instead of a planar reflector. This UTC method utilized ultrasonic radio-frequency echo signals to generate spectral parameters related to the physical properties (e.g., size, shape, and relative acoustic impedance) of tissue microstructures. Three spectral parameters were investigated for quantification of normal-tissue injury: Spectral slope, intercept, and midband fit. They conducted a tissue-mimicking phantom study to verify the reproducibility of UTC measurements and initiated a clinical study of radiation-induced breast-tissue toxicity. Spectral parameter values from measurements on two phantoms were reproducible within 1% of each other. Eleven postradiation breast-cancer patients were studied and significant differences between the irradiated and untreated (contralateral) breasts were observed for spectral intercept (p=0.003) and midband fit (p<0.001) but not for slope (p=0.14). In comparison to the untreated breast, the average difference in the spectral intercept was 2.99±0.75 dB and the average difference in the midband fit was 3.99±0.65 dB. The preliminary clinical study demonstrated the feasibility of using the quantitative ultrasonic method to evaluate normal-tissue toxicity in radiation therapy. [ABSTRACT FROM AUTHOR]

The layout design of a satellite module belongs to a three-dimensional (3D) packing problem with mutual-conflicting performance constraints. Taking the layout design of a simplified commercial communication satellite as a background, based on the cooperative coevolutionary framework, this paper presents a coevolutionary method with heuristic rules for the optimal layout design of a satellite module. First, a whole satellite module layout problem is decomposed into several sublayout problems according to the multisubphysical structure of a satellite module. Second, a relaxation model is adopted to distribute all objects among subspaces. Third, a coevolutionary genetic algorithm is adopted to solve the detailed layout design within the subspaces. Finally, a heuristic combination-rotation (CR) method is adopted to adjust the constraints to obtain the final whole layout scheme. Compared with the coevolutionary approach and the all-at-once optimization approaches, computational results show that the CR method can improve the computational accuracy of solutions and the proposed heuristic coevolutionary method can produces better solutions within short running times. [ABSTRACT FROM AUTHOR]

The pattern and frequency of insertions that enable transposable elements to remain active in a population are poorly understood. The retrotransposable element R2 exclusively inserts into the 28S rRNA genes where it establishes long-term, stable relationships with its animal hosts. Previous studies with laboratory stocks of Drosophila simulans have suggested that control over R2 retrotransposition resides within the rDNA loci. In this report, we sampled 180 rDNA loci of animals collected from two natural populations of D. simulans. The two populations were found to have similar patterns of R2 activity. About half of the rDNA loci supported no or very low levels of R2 transcripts with no evidence of R2 retrotransposition. The remaining half of the rDNA loci had levels of R2 transcripts that varied in a continuous manner over almost a 100-fold range and did support new retrotransposition events. Structural analysis of the rDNA loci in 18 lines that spanned the range of R2 transcript levels in these populations revealed that R2 number and rDNA locus size varied 2-fold; however, R2 activity was not readily correlated with either of these parameters. Instead R2 activity was best correlated with the distribution of elements within the rDNA locus. Loci with no activity had larger contiguous blocks of rDNA units free of R2-insertions. These data suggest a model in which frequent recombination within the rDNA locus continually redistributes R2-inserted units resulting in changing levels of R2 activity within individual loci and persistent R2 activity within the population. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) linear model for digital breast tomosynthesis (DBT) was developed to investigate the effects of different imaging system parameters on the reconstructed image quality. In the present work, experimental validation of the model was performed on a prototype DBT system equipped with an amorphous selenium (a-Se) digital mammography detector and filtered backprojection (FBP) reconstruction methods. The detector can be operated in either full resolution with 85 μm pixel size or 2×1 pixel binning mode to reduce acquisition time. Twenty-five projection images were acquired with a nominal angular range of ±20°. The images were reconstructed using a slice thickness of 1 mm with 0.085×0.085 mm in-plane pixel dimension. The imaging performance was characterized by spatial frequency-dependent parameters including a 3D noise power spectrum (NPS) and in-plane modulation transfer function (MTF). Scatter-free uniform x-ray images were acquired at four different exposure levels for noise analysis. An aluminum (Al) edge phantom with 0.2 mm thickness was imaged to measure the in-plane presampling MTF. The measured in-plane MTF and 3D NPS were both in good agreement with the model. The dependence of DBT image quality on reconstruction filters was investigated. It was found that the slice thickness (ST) filter, a Hanning window to limit the high-frequency components in the slice thickness direction, reduces noise aliasing and improves 3D DQE. An ACR phantom was imaged to investigate the effects of angular range and detector operational modes on reconstructed image quality. It was found that increasing the angular range improves the MTF at low frequencies, resulting in better detection of large-area, low-contrast mass lesions in the phantom. There is a trade-off between noise and resolution for pixel binning and full resolution modes, and the choice of detector mode will depend on radiation dose and the targeted lesion. [ABSTRACT FROM AUTHOR]

During meiosis, cohesin and meiosis-specific proteins organize chromatin into an axis-loop architecture, coordinating homologous synapsis, recombination, and ordered chromosome segregation. However, how the meiotic chromosome axis is assembled and differentiated with meiotic progression remains elusive. Here, we explore the dynamic recruitment of two long arms of the bivalent proteins, LAB-1 and LAB-2, in Caenorhabditis elegans. LAB proteins directly interact with the axis core HORMA complexes and weak interactions contribute to their recruitment. LAB proteins phase separate in vitro, and this capacity is promoted by HORMA complexes. During early prophase, synapsis oppositely regulates the axis enrichment of LAB proteins. After the pachytene exit, LAB proteins switch from a reciprocal localization pattern to a colocalization pattern, and the normal dynamic pattern of LAB proteins is altered in meiotic mutants. We propose that LAB recruitment senses axis differentiation, and phase separation of meiotic structures helps subdomain establishment and accurate segregation of the chromosomes. [ABSTRACT FROM AUTHOR]

The exponential growth of China's economy, coupled with the surge in online commerce, has led to a significant expansion of the logistics industry. In 2022, China's express delivery industry generated approximately 9 million tons of waste paper and 1.8 million tons of plastic. This study analyzed the current composition and utilization of logistics waste in China, with suggestions for recycling. Logistics waste can be defined as the packaging waste generated in the logistics industry. Corrugated paper and plastic waste were chosen as the objects for utilization. Due to its high cellulose content, corrugated paper can be utilized along with other paper waste for biomass resourcing. Biodegradable plastics can also be converted into biomass resources through the action of specific microorganisms. These polymers can be enzymatically depolymerized by certain bacteria and fungi, yielding valuable organic products. In general, logistics wastes all have potential for biomass resource recovery. By adopting appropriate recovery and conversion technologies, these waste streams can be transformed into high-value bio-based products, such as biofuels, biochemicals, and biopolymers, thus contributing to the development of a circular and sustainable economy. [ABSTRACT FROM AUTHOR]

Abstract  A mono-nuclear copper (II) complex 1, formulated {[Cu(phen)2(CO3)]·7H2O} has been synthesized and characterized by X-ray diffraction studies, FTIR, and thermogravimetric (TG) analysis. However, there is a self-assembly structure of (H2O)38 cluster in this complex 1, and it is worth reporting. The adjacent (H2O)38 clusters connect together resulting in an infinite 2D water layer structure. The water morphology is stable at room temperature, but upon thermal decomposition, the water loss is irreversible. Graphical Abstract  A mono-nuclear copper (II) complex 1, formulated {[Cu(phen)2(CO3)].7H2O} has been synthesized and characterized by X-ray diffraction studies, FTIR, and thermogravimetric (TG) analysis. However, there is a self-assembly structure of (H2O)38 water cluster in this complex 1, and it is worth reporting. The discrete (H2O)38 cluster connects together resulting in an infinite 2D water layer structure. The alternate arrangement of the complex 1 and the 2D water layer produce infinite through-channels along a axis direction, and the part moieties of complex 1 are located inside these channels. The water rings are stable at room temperature, and when thermally decomposes the water loss is irreversible. [ABSTRACT FROM AUTHOR]

We have used site-directed mutagenesis and functional analysis to identify positively charged amino acid residues in the cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel that interact with extracellular anions. Mutation of two positively charged arginine residues in the first extracellular loop (ECL) of CFTR, R104, and R117, as well as lysine residue K335 in the sixth transmembrane region, leads to inward rectification of the current–voltage relationship and decreased single channel conductance. These effects are dependent on the charge of the substituted side chain and on the Cl− concentration, suggesting that these positive charges normally act to concentrate extracellular Cl− ions near the outer mouth of the pore. Side chain charge-dependent effects are mimicked by manipulating charge in situ by mutating these amino acids to cysteine followed by covalent modification with charged cysteine-reactive reagents, confirming the location of these side chains within the pore outer vestibule. State-independent modification of R104C and R117C suggests that these residues are located at the outermost part of the pore. We suggest that ECL1 contributes to the CFTR pore external vestibule and that positively charged amino acid side chains in this region act to attract Cl− ions into the pore. In contrast, we find no evidence that fixed positive charges in other ECLs contribute to the permeation properties of the pore. [ABSTRACT FROM AUTHOR]

Using a two-end bonded ZnO piezoelectric-fine-wire (PFW) (nanowire, microwire) on a flexible polymer substrate, the strain-induced change in I− Vtransport characteristic from symmetric to diode-type has been observed. This phenomenon is attributed to the asymmetric change in Schottky-barrier heights at both source and drain electrodes as caused by the strain-induced piezoelectric potential-drop along the PFW, which have been quantified using the thermionic emission−diffusion theory. A new piezotronic switch device with an “on” and “off” ratio of ∼120 has been demonstrated. This work demonstrates a novel approach for fabricating diodes and switches that rely on a strain governed piezoelectric-semiconductor coupling process. [ABSTRACT FROM AUTHOR]

In this article, we report an all-fiber master oscillator power amplifier (MOPA) system, which can provide high repetition rate and nanosecond pulse with diffraction-limit. The system was constructed using a (2 + 1) × 1 multimode combiner. The Q-Switched, LD pumped Nd:YVO4 solid-state laser was used as master oscillator. The 976-nm fiber-coupled module is used as pump source. A 10-m long China-made Yb3+-doped D-shape double-clad large-mode-area fiber was used as amplifier fiber. The MOPA produced as much as 20-W average power with nanosecond pulse and near diffraction limited. The pulse duration is maintained at about 15 ns during 50–175 kHz. The system employs a simple and compact architecture and is therefore suitable for the use in practical applications such as scientific and military airborne LIDAR and imaging. Based on this system, the amplification performances of the all-fiber amplifier is investigated. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2546–2549, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23770 [ABSTRACT FROM AUTHOR]

Alzheimer’s disease (AD) is a neurodegenerative disease resulting in progressive cognitive decline. Amyloid plaque deposits consisting specifically of β-amyloid peptides that have formed fibrils displaying β-pleated sheet conformation are associated with activated microglia and astrocytes, are colocalized with C1q and other complement activation products, and appear at the time of cognitive decline in AD. Amyloid precursor protein (APP) transgenic mouse models of AD that lack the ability to activate the classical complement pathway display less neuropathology than do the APPQ+/+ mice, consistent with the hypothesis that complement activation and the resultant inflammation may play a role in the pathogenesis of AD. Further investigation of the presence of complement proteins C3 and C4 in the brain of these mice demonstrate that both C3 and C4 deposition increase with age in APPQ+/+ transgenic mice, as expected with the age-dependent increase in fibrillar β-amyloid deposition. In addition, while C4 is predominantly localized on the plaques and/or associated with oligodendrocytes in APPQ+/+ mice, little C4 is detected in APPQ−/− brains consistent with a lack of classical complement pathway activation because of the absence of C1q in these mice. In contrast, plaque and cell associated C3 immunoreactivity is seen in both animal models and, surprisingly, is higher in APPQ−/− than in APPQ+/+ mice, providing evidence for alternative pathway activation. The unexpected increase in C3 levels in the APPQ−/− mice coincident with decreased neuropathology provides support for the hypothesis that complement can mediate protective events as well as detrimental events in this disease. Finally, induced expression of C3 in a subset of astrocytes suggests the existence of differential activation states of these cells. [ABSTRACT FROM AUTHOR]

Strain sensors based on individual ZnO piezoelectric fine-wires (PFWs; nanowires, microwires) have been fabricated by a simple, reliable, and cost-effective technique. The electromechanical sensor device consists of a single electrically connected PFW that is placed on the outer surface of a flexible polystyrene (PS) substrate and bonded at its two ends. The entire device is fully packaged by a polydimethylsiloxane (PDMS) thin layer. The PFW has Schottky contacts at its two ends but with distinctly different barrier heights. The I− Vcharacteristic is highly sensitive to strain mainly due to the change in Schottky barrier height (SBH), which scales linear with strain. The change in SBH is suggested owing to the strain induced band structure change and piezoelectric effect. The experimental data can be well-described by the thermionic emission−diffusion model. A gauge factor of as high as 1250 has been demonstrated, which is 25% higher than the best gauge factor demonstrated for carbon nanotubes. The strain sensor developed here has applications in strain and stress measurements in cell biology, biomedical sciences, MEMS devices, structure monitoring, and more. [ABSTRACT FROM AUTHOR]

We demonstrate a mechanical−electrical trigger using a ZnO piezoelectric fine-wire (PFW) (microwire, nanowire). Once subjected to mechanical impact, a bent PFW creates a voltage drop across its width, with the tensile and compressive surfaces showing positive and negative voltages, respectively. The voltage and current created by the piezoelectric effect could trigger an external electronic system, thus, the impact force/pressure can be detected. The response time of the trigger/sensor is ∼10 ms. The piezoelectric potential across the PFW has a lifetime of ∼100 s, which is long enough for effectively “gating” the transport current along the wire; thus a piezoelectric field effect transistor is possible based on the piezotronic effect. [ABSTRACT FROM AUTHOR]

Abstract  A study on the diversity, phylogeny, and host specificity of soybean (Glycine max L.) and peanut (Arachis hypogaea L.) bradyrhizobia was conducted based on the 16S ribosomal RNA (rRNA) restriction fragment length polymorphisms (RFLPs), 16S rRNA sequencing, and 16S–23S rRNA intergenetic spacer (IGS) RFLP assays. Based on 16S rRNA RFLP assay, tested bradyrhizobia were divided into five genotypes, which could be further clustered into five groups by IGS RFLP assays. According to the 16S rRNA sequencing, strains of IGS-II, IV, and V were phylogenetically related to Bradyrhizobium liaoningense, Bradyrhizobium japonicum, and Bradyrhizobium elkanii, while strains of IGS-Ic and IGS-III related to Bradyrhizobium yuanmingense and Bradyrhizobium canariense, respectively. All isolates could crossly nodulate Phaseolus vulgaris, forming small white nodules. Strains of IGS-II originally isolated from peanut could efficiently nodulate Glycine soja, and two strains isolated from soybean could also nodulate peanut. [ABSTRACT FROM AUTHOR]

I K,slow1 and I K,slow2 are two important voltage-gated potassium (K+) currents expressed in mouse ventricular myocytes. However, their properties at the single-channel level have not been characterized. In this paper, we report two new single K+ channels, mK1 and mK2, in myocytes isolated from mouse ventricles and their possible correlation with the macroscopic currents I K,slow1 and I K,slow2. The conductance of mK1 and mK2 was 24 and 17 pS, respectively. Ensemble-averaged current demonstrated an inactivation time constant of 400 to 500 ms for mK1 compared with 1,300 to 2,000 ms for mK2. The mK1 channel was more sensitive than the MK2 channel to the K channel blocker 4-AP. In myocytes isolated from Kv1DN mice with functional knock out of the Kv1.5 channel, mK1 was not detectable but mK2 was present. Our data suggest that the newly characterized K+ channels, mK1 and mK2, likely correspond to the macroscopic currents of I K,slow1 and I K,slow2, respectively. [ABSTRACT FROM AUTHOR]

ABSTRACTSingle-stranded oligonucleotide (SSO)-mediated gene modification is a newly developed tool for site-specific gene repair in mammalian cells; however, the corrected cells always show G2/M arrest and cannot divide to form colonies. This phenomenon and the unclear mechanism seriously challenge the future application of this technique. In this study, we developed an efficient SSO-mediated DNA repair system based on double-stranded break (DSB) induction. We generated a mutant EGFPgene with insertions of 24 bp to 1.6 kb in length as a reporter integrated in mammalian cell lines. SSOs were successfully used to delete the insertion fragments upon DSB induction at a site near the insertion. We demonstrated that this process is dependent on the ATM/ATR pathway. Importantly, repaired cell clones were viable. Effects of deletion length, SSO length, strand bias, and SSO modification on gene repair frequency were also investigated. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is an adaptor/scaffold protein that mediates several important signaling pathways, including the tumor necrosis factor-R:NF-κB pathway, involved in immune surveillance, inflammation, etc. Because most studies of TRAF6 function have focused primarily on its role as an adaptor molecule in signaling pathways in the cytoplasm, the potential functions of TRAF6 in other cellular compartments has not been previously investigated. Here, we demonstrate that TRAF6 resides not only in the cellular cytoplasm but is also found in the nuclei of both normal and malignant B lymphocytes. TRAF6 does not possess a nuclear localization signal but enters the nucleus through the nuclear pore complex containing RanGap1. Chromatin immunoprecipitation cloning experiments demonstrated that nuclear TRAF6 associates with c-Myb within the 5′-end of the c-Myb promoter. Further analysis showed that nuclear TRAF6 is modified by small ubiquitin-related modifier-1, interacts with histone deacetylase 1, and represses c-Myb-mediated transactivation. Thus, TRAF6 negatively regulates c-Myb through a novel repressor function in the nuclei of both normal and malignant B-lymphocytes that could represent a novel control mechanism that maintains cell homeostasis and immune surveillance. [ABSTRACT FROM AUTHOR]

The dispersion of microgels with two interpenetrating polymer networks of poly( N-isopropylacrylamide) and poly(acrylic acid) (PNIPAM-IPN-PAAc) has been studied for its viscoelastic behavior, biocompatibility, and in vivo release properties. The IPN microgels in water had an average hydrodynamic radius of about 85 nm at 21 °C, measured by dynamic light scattering method. The atomic force microscope image showed that the particles were much smaller after they were dried but remained spherical shape. The storage and loss moduli ( G′ and G′′) of dispersions of IPN microgels were measured in the linear stress regime as functions of temperature and frequency at various polymer concentrations using a stress-controlled rheometer. For dispersions with polymer concentrations of 3.0 and 6.0 wt % above 33 °C, the samples behave as viscoelastic solids and the storage modulus was larger than the loss modulus over the entire frequency range. The loss tangent was measured at various frequencies as a function of temperature. The gelation temperature was determined to be 33 °C at the point where a frequency-independent value of the loss tangent was first observed. At pH 2.5, when heated above the gelation temperature, IPN microgels flocculate by pumping a large amount of water from the gel. When the pH value was adjusted to neutral, deprotonation of −COOH groups on PAAc made the microgel keep water even above the gelation temperature. Using an animal implantation model, the biocompatibility and drug release properties of the IPN microgel dispersion were evaluated. Fluorescein as a model drug was mixed into an aqueous microgel dispersion at ambient temperature. This drug-loaded liquid was then injected subcutaneously in Balb/C mice from Taconic Farms. The test results have shown that the IPN microgels did not adversely promote foreign body reactions in this acute implantation model and the presence of gelled microgel dispersion substantially slowed the release of fluorescein. [ABSTRACT FROM AUTHOR]

Current image processing and pattern recognition algorithms are not robust enough to make automated remote sensing image interpretation feasible. For this reason, we need to develop image interpretation systems that rely on human guidance. In this paper, we tackle the problem of semiautomatic road tracking in aerial photos. We propose an online learning approach that naturally integrates inputs from human experts with computational algorithms to learn road tracking. Human inputs provide the online learner with training examples to generate road predictors. An ensemble of road predictors is learned incrementally and used to automatically track roads. When novel situations are encountered, control is returned back to the human expert to initialize a new training and tracking iteration. Our approach is computationally efficient, and it can rapidly adapt to dynamic situations where the image feature distributions change. Experimental results confirm that our approach is effective and superior to existing methods. [ABSTRACT FROM AUTHOR]

New species with molecular formula Si2NS, not yet observed experimentally, are described theoretically for the first time. Various levels of calculations are applied to obtain the structures, energies, dipole moments, vibrational spectra, rotational constants, and isomerization of Si2NS species. A total of 15 minima which are connected by 21 interconversion transition states on the potential energy surface are located at the DFT/B3LYP/6-311G(d) level of theory. And at the higher (single point) CCSD(T)/6-311+G(2d)//QCISD/6-311G(2d)+ZPVE level of theory, the global state of 1 (at 0.0 kcal/mol) corresponds to a nonlinear SiNSiS with a 2A′ electronic state. The next most stable isomer of 2 (only 3.7 kcal/mol higher 1) possesses a rhomboidal-type structure similar to the global state of Si2NO. This is followed by another local minimum of 6 (at 43.8 kcal/mol above 1) which is a nonlinear SiNSSi form with a 2A′ electronic state. Note that both 1 and 6 have the important Si≡N triple bonding. Too, the analog of (NCCS) NSiSiS is unstable due to the higher energy of its own. The bonding natures of the relevant species are also discussed. An analysis of the bonding properties and structural similarities and differences between C2NO, C2NS, SiCNO, and Si2NO is also carried out. [ABSTRACT FROM AUTHOR]

Human hepatocellular carcinoma (HCC) is one of the most mortal tumor. In a previous study, we had constructed glycoprotein expression profiles and glycoprotein databases of three human liver cancer cell lines with diverse metastasis potential. In order to discover vital glycoproteins related to pathogenesis and metastasis of HCC, in this study we analyzed previous data with bioinformatic approach. We took previous data to draw the protein–protein interaction (PPI) networks of liver cell lines by searching IntACT database and then using Pajeck software. Further more, we compared the differences between the three PPI networks by drawing the PPI networks of differential glycoproteins and by naming differential display PPI networks. Large numbers of proliferation and apoptosis-relative proteins interact with the differential glycoproteins, and among the differential glycoproteins there are many interactions. We conclude that neither single nor several proteins cause malignant proliferation of liver cells. “Molecule groups” concept should be introduced into diagnosis and metastasis prediction of the HCC. [ABSTRACT FROM AUTHOR]

Abstract  We report molecular cloning and single nucleotide polymorphism detection of the buffalo DGAT1 gene. Diacylglycerol acyltransferase (DGAT1) is considered the key enzyme in controlling the rate of synthesis of triglycerides. The DGAT1 gene was recently identified as a strong functional candidate gene affecting milk yield and composition in cattle. A full-length buffalo DGAT1 genomic DNA was amplified by iterative PCR based on homolog cloning. The buffalo DGAT1 gene comprises 17 exons and spans approximately 8.3 kb. The genomic structures of DGAT1 are highly conserved among mammal species. The deduced protein of buffalo DGAT1 contains 489 amino acids, showing high-sequence similarity with mammal homologs. Through PCR-SSCP analysis and sequencing, seven polymorphic positions were detected in the complete genomic region of buffalo DGAT1, and their frequencies were observed from a collection of 117 buffalo. The SNP (C/T) detected at position 11785 in exon 17 creates a substitution change for the amino acid sequence, resulting in an Ala residue (GCG) transition to a Val residue (GTG) in position 484 of buffalo DGAT1 protein. Information provided in this study will be useful in further studies to determine the role DGAT1 plays in the regulation of milk fat synthesis and quality improvement for milk in buffalo. [ABSTRACT FROM AUTHOR]

Abstract  Light-pulse propagation in one-dimensional photonic crystals is studied by a finite-difference time-domain method. The effect of the group-velocity dispersion is connected with the center frequency of the light pulse: when it is close to the edge of the photonic band gap, the light pulse undergoes a large group-velocity dispersion. If a nonlinearity is introduced into the photonic-crystal material, a soliton-like pulse can occur. The velocity of the light pulse inside the photonic crystal is calculated. [ABSTRACT FROM AUTHOR]

To extensively investigate the glycoproteins of normal human liver tissue, constructing the glycoprotein profile and database of the normal human liver tissue. The total proteins were extracted from the normal human liver tissue and then subjected to two-dimensional electrophoresis (2-DE). Finally, 2-DE gels were stained according to the methods of multiplexed proteomics (MP) technology. Glycoprotein spots were excised from 2-DE gel and then characterized by matrix assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS). The PDQuest software detected 1,011 glycoprotein spots and 1,923 total protein spots in the 2-DE gels of sample from the normal human liver tissue. Furthermore, 116 species of glycoproteins were successfully identified via peptide mass profiling using MALDI-TOF-MS/MS and annotated to our databases. In addition, we also applied bioinformatics softwares to predict N- or O-glycosylation sites of identified glycoproteins. This study demonstrates the feasibility of a novel technological platform to contruct glycoprotein databases. These results lay the foundation for future physiological and pathological studies of the human liver. [ABSTRACT FROM AUTHOR]

The cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel pore is thought to contain multiple binding sites for permeant and impermeant anions. Here, we investigate the effects of mutation of different positively charged residues in the pore on current inhibition by impermeant Pt(NO2) and suramin anions. We show that mutations that remove positive charges (K95, R303) influence interactions with intracellular, but not extracellular, Pt(NO2) ions, consistent with these residues being situated within the pore inner vestibule. In contrast, mutation of R334, supposedly located in the outer vestibule of the pore, affects block by both extracellular and intracellular Pt(NO2). Inhibition by extracellular Pt(NO2) requires a positive charge at position 334, consistent with a direct electrostatic interaction resulting in either open channel block or surface charge screening. In contrast, inhibition by intracellular Pt(NO2) is weakened in all R334-mutant forms of the channel studied, inconsistent with a direct interaction. Furthermore, mutation of R334 had similar effects on block by intracellular suramin, a large organic molecule that is apparently unable to enter deeply into the channel pore. Mutation of R334 altered interactions between intracellular Pt(NO2) and extracellular Cl− but not those between intracellular Pt(NO2) and extracellular Pt(NO2). We propose that while the positive charge of R334 interacts directly with extracellular anions, mutation of this residue also alters interactions with intracellular anions by an indirect mechanism, due to mutation-induced conformational changes in the protein that are propagated some distance from the site of the mutation in the outer mouth of the pore. [ABSTRACT FROM AUTHOR]

Controllability of linear continuous-time periodic systems is dealt with via a harmonic analysis approach for the first time in this paper. This approach reveals that controllability of continuous-time periodic systems can be connected to necessary and sufficient conditions expressed explicitly with Fourier coefficients of the system matrices, which can be interpreted in a way similar to what we have seen in linear time-invariant cases. These controllability conditions shed new light upon structural characteristics of continuous-time periodic systems that are hard to know by means of existing time-domain controllability criteria in the literature. Controllability canonical decomposition of linear continuous-time periodic systems is revisited through state coordinate transforms of strong analytic features. The results are heuristic and significant for examining structural characteristics of continuous-time periodic systems and extending controllability-related techniques that are widely employed in linear time-invariant systems to linear continuous-time periodic systems. [ABSTRACT FROM AUTHOR]

Objective To investigate whether the effect of E. coli on U937 cell lines apoptosis is mediated via p38 mitogen-activated protein kinase (MAPK) activation. Methods The U937 cell lines were treated with E. coli at different time or together with SB203580, an inhibitor for p38. Cell apoptosis was analyzed by flow cytometry. p38 activities were detected by Western blotting. Results E. coli induced apoptosis in cultured U937 cell lines in a time-dependent manner. The phosphorylation of p38 was induced after 10 minutes infection, reached the peak after 20 minutes, and started to decline after 30 minutes. In contrast, the level of total p38 protein was not changed in whole experimental period. Inhibition of p38 with SB203580 significantly inhibited E. coli induced apoptosis in U937 cells. Conclusion The activation of the p38 MAPK in U937 cell lines by E. coli is a major pathway to mediate the apoptosis. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the pharmacokinetics of mycophenolic acid (MPA) in Chinese adult renal allograft recipients, and to generate the validated model equations for estimation of the MPA area under the plasma concentration-time curve from 0 to 12 hours (AUC12) with a limited sampling strategy. Patients and methods: The pharmacokinetics in 75 Chinese renal allograft recipients treated with mycophenolate mofetil 2 g/day in combination with ciclosporin and corticosteroids were determined. The MPA concentration was assayed by high-performance liquid chromatography at pre-dose (Co) and at 0.5 (Co.s), 1 (C1), 1.5 (C1.5), 2 (C2), 4 (C4), 6(C6), 8 (C8), 10(C10) and 12 (C12) hours after dosing on day 14 post-transplant. Patients were randomly divided into: (i) a model group (n = 50) to generate the model equations by multiple stepwise regression analysis for estimation of the MPA AUC by a limited sampling strategy; and (ii) a validation group (n = 25) to evaluate the predictive performance of the model equations. Results: The mean MPA AUCI2 was 52.97 ± 15.09 mg • h/L, ranging from 24.0 to 102.3 mg • h/L. The patient's age and serum albumin level had a significant impact on the MPA AUC12. The correlation between the pre-dose MPA trough level (Cci) and the MPA AUCI2 was poor (r2 = 0.02, p = 0.33). Model equations 7 (MPA AUC12 = 14.81 + 0.80 • C0.5 + 1.56 • C2 + 4.80 • C4, r2 = 0.70) and 11 (MPA AUC12 = 11.29 + 0.51 .Co.5 + 2.13 •C2 + 8.15•C8, r2 0.88) were selected for MPA AUC calculation in Chinese patients, resulting in good agreements between the estimated MPA AUC12 and the full MPA 12, with a mean prediction error of ±10.1 and ±6.9 mg • h/L, respectively. Conclusion: In Chinese renal allograft recipients, MPA pharmacokinetics manifest substantial interindividual variability, and the MPA AUC12 tends to be higher than that in Caucasian patients receiving the same dose of mycophenolate mofetil. Two validated model equations with three sampling timepoints are recommended for MPA AUC estimation in Chinese patients. [ABSTRACT FROM AUTHOR]

The Bumo gold deposit is a low-sulfide quartz vein type deposit, situated in the west of Hainan Island, approximately 25 km southeast of Dongfang City (termed Basuo in alias). Tectonically, the SW-NE-oriented Gezhen Ductile-Shearing Zone was largely attenuated in Bumo. It is hosted by gneisses and schists of Proterozoic age (locally called the Baoban Group), but the radiometric age of ores mainly is Jurassic–Cretaceous, being coeval to the regional metallogenesis along the Eurasian margin. The affinity with the Phanerozoic orogenic gold deposits is indicated by low salinity (2.4 wt% NaCl–10.3 wt% NaCl), intermediate temperature (150–300°C) and appropriate δ18O value (approximately 7–11‰). The gold metal tonnage, proved previously, within an area smaller than 1.0 km2 in the gold belt II amounted to 11.59 t, with the average gold grades for the major Au quartz veins (7 and 8) in this belt of 52.7 and 71.1 g/t, respectively. This shows significant enrichment of gold and an unusual “nugget effect”. A ring structure, mainly represented by ridges, valleys, dikes, big bull quartz veins and lithological borders or pertinent faults, marks the gold field, and its origin was linked to a possible magmatic diapir. It was viewed as macroscopic evidence that the dip angles of strata tend to decline gradually from deeper ones in the center area to nearly horizontal in the outskirts, and certain intrusion-affiliated elements such as Bi, As and W are considerably abundant in soil samples. Two areas, namely the area A (3.06 km2) in the outskirts of the ring structure or in northeastern Bumo and the area B (1.32 km2) in the field center or to the west of the gold belts I and II, were selected for the geochemical survey in a 50 × 50-m sampling grid. The analytical results of the samples from horizon C and in a −80 mesh size showed that the average contents of Bi, As and W amounted to 0.55, 19.3 and 3.67 ppm in the area A (1225 samples) and to 0.79, 68.3 and 4.14 ppm in the area B (529 samples), respectively. This geochemical exploration led to the discovery of several Au quartz veins in both areas A and B, which also manifested an Au nugget effect (the average Au grades between 50 and 100 g/t) in spite of their limited scales (from a couple of centimeters to 50 cm wide and from several meters to 15 m long). A mylonite zone in area A was also found by this study. An intimate spatial correlation between a lithological border (gneiss and schist or pegmatite) or the mylonite zone and Au anomalies indicates an important prospect for further gold exploration. [ABSTRACT FROM AUTHOR]

In breast tomosynthesis there is a compromise between resolution, noise, and acquisition speed for a given glandular dose. The purpose of the present work is to develop a simulation platform to investigate the potential imaging performance for the many possible tomosynthesis system configurations. The simulation platform was used to investigate the dependence of image blur and signal difference to noise ratio (SDNR) for several different tomosynthesis acquisition configurations. Simulated projections of a slanted thin tungsten wire placed in different object planes were modified according to the detector’s modulation transfer function (MTF), with or without pixel binning. In addition, the focal spot blur (FSB), which depends on the location of the wire, the system geometry, the source-detector movement speed, and the exposure time, was also incorporated into the projections. Both expectation maximization (EM) and filtered back projection (FBP) based algorithms were used for 3D image reconstruction. The in-plane MTF was calculated from the reconstructed image of the wire. To evaluate the noise performance, simulated noiseless projections of calcification and tumor in uniform breast tissue were modified with the noise power spectrum (NPS) calculated from a cascaded linear system model for the detector for a given x-ray dose. The SDNR of the reconstructed images was calculated with different tomosynthesis configurations, e.g., pixel binning, view number, and angular range. Our results showed that for a source-to-imager distance (SID) of 66 cm, pixel binning (2×2) caused more degradation to the in-plane MTF than the blur caused by the moving focal spot and reconstruction. The in-depth resolution can be improved by increasing the angular range. [ABSTRACT FROM AUTHOR]

Utilizing the coupled piezoelectric and semiconducting dual properties of ZnO, we demonstrate a piezoelectric field effect transistor (PE-FET) that is composed of a ZnO nanowire (NW) (or nanobelt) bridging across two Ohmic contacts, in which the source to drain current is controlled by the bending of the NW. A possible mechanism for the PE-FET is suggested to be associated with the carrier trapping effect and the creation of a charge depletion zone under elastic deformatioin. This PE-FET has been applied as a force/pressure sensor for measuring forces in the nanonewton range and even smaller with the use of smaller NWs. An almost linear relationship between the bending force and the conductance was found at small bending regions, demonstrating the principle of nanowire-based nanoforce and nanopressure sensors. [ABSTRACT FROM AUTHOR]

The article discusses the concept of reactive compatibility of nano-silca particles with polypropylene (PP) composites. The particles were grafted chemically with polyglycidly metacrylate that has reactive epoxide groups. The grafted particles are melt with PP and amine functionalized PP. The amine group serves as the reactive compatibilizer. The formation of chemical bonds shows the efficiency of reactive compatibilization in providing mechanical performance of nano-silca particles/PP.

The article cites an experiment on the fracture toughness for polymethyl methacrylate (PMMA) using the Brazilian disk specimen. This will determine the effect of notch shape and the relative notch length on the measurement of mode-I fracture toughness. The Shimadzu-500 testing machine was loaded into the Brazilian disk. The results showed that the critical stress intensity factor measured from sharp-notched specimen can be considered as the fracture toughness of PMMA material.

This paper presents the experimental observation of piezoelectric generation from a single ZnO wire/belt for illustrating a fundamental process of converting mechanical energy into electricity at nanoscale. By deflecting a wire/belt using a conductive atomic force microscope tip in contact mode, the energy is first created by the deflection force and stored by piezoelectric potential, and later converts into piezoelectric energy. The mechanism of the generator is a result of coupled semiconducting and piezoelectric properties of ZnO. A piezoelectric effect is required to create electric potential of ionic charges from elastic deformation; semiconducting property is necessary to separate and maintain the charges and then release the potential via the rectifying behavior of the Schottky barrier at the metal−ZnO interface, which serves as a switch in the entire process. The good conductivity of ZnO is rather unique because it makes the current flow possible. This paper demonstrates a principle for harvesting energy from the environment. The technology has the potential of converting mechanical movement energy (such as body movement, muscle stretching, blood pressure), vibration energy (such as acoustic/ultrasonic wave), and hydraulic energy (such as flow of body fluid, blood flow, contraction of blood vessels) into electric energy that may be sufficient for self-powering nanodevices and nanosystems in applications such as in situ, real-time, and implantable biosensing, biomedical monitoring, and biodetection. [ABSTRACT FROM AUTHOR]

Poly(vinyl pyrrolidone)-capped multiple twinned gold (Au) particles withdecahedral shape have been synthesized by a simple and convenient solvothermalwet chemical method. In the process, hydrogen tetrachloroauric acid(HAuCl43H2O) was reduced by ethylene glycol (EG) to form the multiple twinned Aunanocrystals in the presence of poly(vinyl pyrrolidone) (PVP) molecules at200 C under the extra condition of autogenous pressure. The decahedral nanoparticlestake up about 10% of the total amount and have the usual size distribution fromseveral tens to hundreds of nanometres. Some larger microsized five-twinned Auparticles with perfect decahedral shape have also been observed in the final product.Furthermore, x-ray photoelectron spectroscopy (XPS) measurements verified thatPVP molecules are adsorbed on the surface of the Au particles. Based on theexperimental results, a growth mechanism has been suggested to elucidate theformation of the small decahedral Au nanoparticles as well as their evolutioninto perfect large decahedral Au particles with the size of several micrometres. [ABSTRACT FROM AUTHOR]

The pathogenesis of acute promyelocytic leukemia involves the transcriptional repression of master genes of myeloid differentiation by the promyelocytic leukemia-retinoic acid receptor α (PML/RARA) oncogene. PML-enforced RARA homodimerization allows the tighter binding of corepressors, silencing RARA target genes. In addition, homodimerization dramatically extends the spectrum of DNA-binding sites of the fusion protein compared with those of normal RARA. Yet, any contribution of these two properties of PML/RARA to differentiation arrest and immortalization of primary mouse hematopoietic progenitors was unknown. We demonstrate that dimerization-induced silencing mediator of retinoid and thyroid receptors (SMRT)-enhanced binding and relaxed DNA-binding site specificity are both required for efficient immortalization. Thus, enforced RARA dimerization is critical not only for triggering transcriptional repression but also for extending the repertoire of target genes. Our studies exemplify how dimerization-induced gain of functions converts an unessential transcription factor into a dominant oncogenic protein. [ABSTRACT FROM AUTHOR]

Large-area aligned Mo nanowires have been grown on stainless steel substrates by high-temperature chemical vapor deposition with the use of Mo metal. The detailed physical and chemical growth processes regarding the formation of the nanowires have been investigated using mass spectroscopy, thermogravimetry, and differential scanning calorimetry analysis, as well as structure analysis by electron microscopy. In reference to Gibbs energy calculation, our study reveals that the growth relies on the decomposition of MoO2vapors through condensation of its vapor at high substrate temperatures. The aligned growth is a result of competing growth with the nanowires normal to the substrate surface reaching the final growth front. The field emission measurement and the vacuum luminescent tube study show that the Mo nanowires have potential application as electron emitters. [ABSTRACT FROM AUTHOR]

The properties of binary blazed grating were theoretically analyzed with finite-difference time -domain (FDTD) method. The diffraction efficiencies and diffraction angles of -1, 0, and +1 order for the grating varying with wavelength, grating structure, and the etch depth were studied when the incident angle was 30°. The numerical simulations revealed that the binary blazed grating presented high stability of diffraction efficiencies with wavelength shift. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of hepatocyte growth factor(HGF) on vascular endothelial cells apoptosis induced by advanced glycation end products(AGEs) and its possible mechanism. Methods Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and intervened by different concentrations of AGEs and HGF. The cell inhibitory rates of each group with different culture time( 12, 24, 48, and 72 hours)were measured by methyl thiazolyl tetrazolium(MTT) assay. The early stage apoptosis was detected by flow cytometry with Annexin V-FITC/PI double staining, morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the expression of apoptosis-associated genes Bax and Bcl-2 were determined by Western blotting. The activity of caspase-3 was detected by enzyme-linked immunosorbent assay (ELISA). Results Morphological observation indicated that high concentration of AGEs induced characteristic apoptotic changes in HUVECs. Within a certain concentration range, HUVECs apoptosis inducing rates by AGEs were in both dose- and time-dependent manners. HGF significantly inhibited the apoptosis of HUVECs induced by AGEs (P < 0.05 ). AGEs significantly promoted expression of Bax protein, but not Bcl-2. Whereas HGF significantly promoted the expression of Bcl-2 ( P < 0.01 ) and decreased the activity of caspase-3 ( P < 0. 05 ) without affecting Bax level. Conclusions AGEs can induce the apoptosis of endothelial cells in vitro. HGF may effectively attenuate AGEs-induced endothelial cells apoptosis through upregulating Bcl-2 gene expression and inhibiting caspase-3 activation. [ABSTRACT FROM AUTHOR]

Dihydroartemisinin (DHA), a more water-soluble active metabolite of artemisinin derivatives, is safe and the most effective antimalarial analog of artemisinin. In the present investigation, we assessed the effect of DHA on vascular endothelial growth factor (VEGF) expression and apoptosis in chronic myeloid leukemia (CML) K562 cells. The results demonstrated that in addition to its antiproliferation effect on CML cells, DHA was also found to induce K562 cells apoptosis. The percentage of apoptotic cells was increased to 6.9 and 15.8% after being treated with 5 and 10 μmol/l DHA for 48 h, respectively (P<0.001). In order to analyze the effect of DHA on VEGF expression in K562 cells, we assessed the level of VEGF expression by western blot; detected the form of VEGF mRNA by RT-PCR and examined the level of VEGF secreted in conditioned media (CM) by ELISA assay. All these experiments suggested that DHA could inhibit the VEGF expression and secretion effectively in K562 cells, even at a lower concentration (2 μmol/l, P<0.05). Moreover, we further assessed the stimulating angiogenic activity of CM from K562 cells on CAM model. The angiogenic activity was decreased in response to the CM from K562 cells pretreated with DHA in a dose-dependent manner. Taken together, these results from our study together with its known low toxicity make it possible that DHA might present potential antileukemia effect as a treatment for CML therapy, or as an adjunct to standard chemotherapeutic regimens. [ABSTRACT FROM AUTHOR]

First, by using the 2-regularized determinant technique for Hilbert--Schmidt operators, the computation formula, infinite-product convergence, and analyticity of the 2-regularized determinant of the modified harmonic state operator in finite-dimensional linear continuous-time periodic (FDLCP) systems are derived in this paper. Second, based on these results, a 2-regularized Nyquist criterion is established for asymptotic stability analysis of a class of FDLCP systems for the first time. Third, a numeric implementation algorithm for the 2-regularized Nyquist criterion is also proposed via the staircase truncation on the harmonic transfer operator of the FDLCP system concerned. Finally, to illustrate the results of this paper, asymptotic stability of the lossy Mathieu differential equation is investigated. [ABSTRACT FROM AUTHOR]

Long-term potentiation (LTP) of C-fiber-evoked field potentials in spinal dorsal horn may be relevant to pathological pain. Our previous work has shown that the late phase of the spinal LTP is protein synthesis-dependent. Considerable evidence has accumulated that dopamine D1/D5 receptors are important for late-phase LTP in hippocampus. In this study, the role of D1/D5 receptors in LTP of C-fiber-evoked field potentials in spinal dorsal horn was evaluated in urethan-anesthetized Sprague-Dawley rats. We found the following. 1) Spinal application of SKF 38393, a D1/D5 receptor agonist, induced a slowly developed LTP of C-fiber-evoked field potentials, lasting for >10 h, and the effect was blocked by the D1/D5 antagonist SCH 23390, whereas a D2 receptor agonist (quinpirole) induced depression of C-fiber responses, lasting for 2 h. 2) The potentiation produced by D1/D5 receptor agonist occluded the late phase but not the early phase of the spinal LTP produced by tetanic stimulation. 3) SCH 23390 selectively depressed the late-phase LTP, when applied 40 min before tetanic stimulation. 4) The D1/D5 agonist-induced potentiation is blocked by the protein synthesis inhibitor anisomycin. 5) Activation of protein kinase A by spinal application of 8-Br-cAMP also induced spinal LTP, and the action occluded the potentiation induced by the D1/D5 receptor agonist. These results suggest that the spinal D1/D5 receptors participate in the protein synthesis-dependent late-phase LTP of C-fiber-evoked field potentials in spinal dorsal horn through the cAMP signaling pathway. [ABSTRACT FROM AUTHOR]

Since the 1980s, dozens of Chinese government documents on teacher education reform have been published. These documents have influenced the direction of teacher education change in China and will continue to do so in the years ahead. The first wave of documents focused on recovering the teacher education system. A second wave centered on building a mechanism of quality assurance for teaching as a profession. A third wave concentrated on raising the quality of teacher education. This paper summarizes the implementation of these documents and comments on the benefits and challenges of the major components of the three waves of reform as they relate to teacher education. [ABSTRACT FROM AUTHOR]

Drug resistance, in particular multidrug resistance, is a serious problem that impedes the effectiveness of chemotherapy. Multidrug resistance results mainly from an enhanced efflux of drugs by drug pumps located on the cell membrane such as P-glycoprotein. In the study reported here we showed that EM012, a microtubule-interfering agent, is a weak substrate for P-glycoprotein and inhibited the proliferation of A2780/ADR human ovarian cancer cells, which possess multidrug resistance due to P-glycoprotein overexpression. A2780/ADR cells treated with EM012 exhibited pronounced mitotic arrest, developed large multilobed nuclei, and eventually died through the initiation of apoptosis. Intraperitoneal treatment of A2780/ADR xenograft tumors in athymic nude mice with EM012 significantly inhibited tumor progression through triggering apoptosis and conferred an apparent survival advantage. Furthermore, EM012 treatment did not cause detectable toxicity to normal tissues. These findings suggest that EM012 may serve as a novel chemotherapeutic agent for the treatment of multidrug-resistant human ovarian cancer. [ABSTRACT FROM AUTHOR]

Heat stress can alert innate immunity by inducing stress proteins such as heat-shock proteins (HSPs). However, it remains unclear whether heat stress affects the activation of antigen-presenting cell (APC) in response to pathogen-associated molecule patterns (PAMPs) by directly regulating pathogen recognition receptors (PRRs). As an important kind of PRRs, Toll-like receptors (TLRs) play critical roles in the activation of immune system. In this study, we demonstrated that heat shock up-regulated the expression of HSP70 as well as TLR2 and TLR4 in monocytes. The induction of TLRs was prior to that of HSP70, which suggesting the up-regulation of TLR2 and TLR4 might be independent of the induction of HSP70. Heat shock activated p38 kinase, extracellular signal-related kinase (ERK) and nuclear factor-kappa B (NF-κB) signal pathways in monocytes. Pretreatment with specific inhibitor of p38 kinase, but not those of ERK and NF-κB, inhibited heat shock-induced up-regulation of TLR2 and TLR4. This indicates that p38 pathway takes part in heat shock-induced up-regulation of TLR2 and TLR4. Heat shock also increased lipoteichoic acid- or lipopolysaccharide-induced interleukin-6 production by monocytes. These results suggest that the p38 kinase-mediated up-regulation of TLR2 and TLR4 might be involved in the enhanced response to PAMP in human monocytes induced by heat shock. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease, a common dementia of the elder, is characterized by accumulation of protein amyloid deposits in the brain. Immunization to prevent this accumulation has been proposed as a therapeutic possibility, although adverse inflammatory reactions in human trials indicate the need for novel vaccination strategies. Method: Here vaccination with novel amyloid peptide immunogens was assessed in a transgenic mouse model displaying age-related accumulation of fibrillar plaques. Results: Immunization with any conformation of the amyloid peptide initiated at 12 months of age (at which time fibrillar amyloid has just begun to accumulate) showed significant decrease in total and fibrillar amyloid deposits and in glial reactivity relative to control transgenic animals. In contrast, there was no significant decrease in amyloid deposition or glial activation in mice in which vaccination was initiated at 16 months of age, despite the presence of similar levels anti-Aβ antibodies in young and old animals vaccinated with a given immunogen. Interestingly, immunization with an oligomeric conformation of Aβ was equally as effective as other amyloid peptides at reducing plaque accumulation. However, the antibodies generated by immunization with the oligomeric conformation of Aβ have more limited epitope reactivity than those generated by fAβ, and the microglial response was significantly less robust. Conclusion: These results suggest that a more specific immunogen such as oligomeric Aβ can be designed that achieves the goal of depleting amyloid while reducing potential detrimental inflammatory reactions. In addition, the data show that active immunization of older Tg2576 mice with any amyloid conformation is not as efficient at reducing amyloid accumulation and related pathology as immunization of younger mice, and that serum anti-amyloid antibody levels are not quantitatively related to reduced amyloid-associated pathology. [ABSTRACT FROM AUTHOR]

Background: During infection and inflammation, circulating blood monocytes migrate from the intravascular compartments to the extravascular compartments, where they mature into tissue macrophages. The maturation process prepares the cells to actively participate in the inflammatory and immune responses, and many factors have been reported to be involved in the process. We found in our study that CD147 played a very important role in this process. Results: By using PMA-differentiated human monocyte cells line THP-1, we found that CD147 mediated matrix metalloproteinases (MMPs) expression of the leukemic THP-1 cells and thus enhanced the invasiveness of THP-1 cells. After 24 hours of PMA-induced monocyte differentiation, the mean fluorescence intensity of CD147 in differentiated THP-1 cells (289.61 ± 31.63) was higher than that of the undifferentiated THP-1 cells (205.1 ± 19.25). There was a significant increase of the levels of proMMP-2, proMMP-9 and their activated forms in the differentiated THP-1 cells. Invasion assays using reconstituted basement membrane showed a good correlation between the invasiveness of THP-1 cells and the production of MMP-2 and MMP-9. The difference in the MMPs expression and the invasive ability was significantly blocked by HAb18G/CD147 antagonistic peptide AP-9. The inhibitory rate of the secretion of proMMP-9 in the undifferentiated THP-1 cells was 45.07%. The inhibitory rate of the secretion of proMMP-9, the activated MMP-9 and proMMP-2 in the differentiated THP-1 cells was 52.90%, 53.79% and 47.80%, respectively. The inhibitory rate of invasive potential in the undifferentiated cells and the differentiated THP-1 cells was 41.82 % and 25.15%, respectively. Conclusion: The results suggest that the expression of CD147 is upregulated during the differentiation of monocyte THP-1 cells to macrophage cells, and CD147 induces the secretion and activation of MMP-2 and MMP-9 and enhances the invasive ability of THP-1 cells. The matured monocytes / macrophages, via their high expression of CD147, may play an important role in promoting the tissue repair or tissue damage during their inflammatory response. [ABSTRACT FROM AUTHOR]

—Thermally-responsive hydrogel nanoparticles of poly(N-isopropylacrylamide) (PNIPAM) and hydroxypropyl cellulose (HPC) have been synthesized. The particle size has been correlated to surfactant concentration and polymer concentration using dynamic laser light scattering techniques. The tissue compatibility of these hydrogel nanoparticles has been evaluated by comparing with poly-L-lactic acid and polystyrene nanoparticles using a mouse implantation model. Our results suggested that both PNIPAM and HPC nanoparticles triggered lesser inflammatory and fibrotic responses among all nanoparticles tested. It is likely that these hydrogel nanoparticles may be suitable for tissue augmentation or drug-delivery devices. [ABSTRACT FROM AUTHOR]