Differences in the stimulation of cyclic electron flow in two tropical ferns under water stress are related to leaf anatomy

Cyclic electron flow (CEF) plays an important role in photoprotection for angiosperms under environmental stresses. However, ferns are more sensitive to drought and their water transport systems are not as efficient as those of angiosperms, it is unclear whether CEF also contributes to photoprotection in these plants. Using Microsorum punctatum and Paraleptochillus decurrens, we studied the electron fluxes through both photosystem I (PSI) and photosystem II (PSII) under water stress and their leaf anatomies. Our goal was to determine if CEF functions in the photoprotection of these ferns and, if so, whether CEF stimulation is related to leaf anatomy. Compared with P. decurrens, M. punctatum had thicker leaves and cuticles and higher water storage capacity, but lower stomatal density and slower rate of water loss. During induced drought, the decrease in leaf water potential (Ψ(leaf) ) was more pronounced in P. decurrens than in M. punctatum. For both species, the decline in Ψ(leaf) was associated with a lower effective PSII quantum yield, photochemical quantum yield of PSI and electron transport rate (ETR), whereas increases were found in the quantum yield of regulated energy dissipation, CEF and CEF/ETR(II) ratio. Values for CEF and the CEF/ETR(II) ratio peaked in M. punctatum at a light intensity of 500-600 µmol m(-2) s(-1) vs only 150-200 µmol m(-2) s(-1) in P. decurrens. Therefore, our results indicate that the stimulation of CEF in tropical ferns contributes to their photoprotection under water stress, and is related to their respective drought tolerance and leaf anatomy.

Less stress, more success? Oncological implications of surgery-induced oxidative stress

Reactive oxygen species (ROS) possess important cell signalling properties. This contradicts traditional thought which associated ROS activity with cell death. Emerging evidence clearly demonstrates that ROS signalling acts as a key regulator in tumour cell survival and in the cellular processes required for tumour cells to successfully metastasise and proliferate. The discovery of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) family of enzymes in the last decade has unravelled much of the mystery surrounding how ROS are generated. Tumour cells are now known to express Nox enzymes which produce ROS required for cellular signalling. Activation of Nox enzymes occurs via interaction with proinflammatory cytokines and growth factors, all of which are released following surgical trauma. As our understanding of the signalling capabilities of ROS grows, the oncological implications of ROS activity are gradually being revealed. Nox-derived ROS are known to play a central role in each step of the metastatic cascade including invasion, adhesion, angiogenesis and proliferation. This article describes how surgery creates a ROS-rich environment, which facilitates redox signalling, and also examines the role played by Nox enzymes in this process. The authors then explore current knowledge of the oncological implications of surgery-induced redox signalling, and discuss current and future therapeutic strategies targeted at ROS and Nox enzymes in cancer patients.

Characterization of the interaction between astrocytes and encephalitogenic lymphocytes during the development of experimental autoimmune encephalitomyelitis (EAE) in mice

The nature of pathogenic mechanisms associated with the development of multiple sclerosis (MS) have long been debated. However, limited research was conducted to define the interplay between infiltrating lymphocytes and resident cells of the central nervous system (CNS). Data presented in this report describe a novel role for astrocyte-mediated alterations to myelin oligodendrocyte glycoprotein (MOG)(35-55) -specific lymphocyte responses, elicited during the development of experimental autoimmune encephalitomyelitis (EAE). In-vitro studies demonstrated that astrocytes inhibited the proliferation and interferon (IFN)-γ, interleukin (IL)-4, IL-17 and transforming growth factor (TGF)-β secretion levels of MOG(35-55) -specific lymphocytes, an effect that could be ameliorated by astrocyte IL-27 neutralization. However, when astrocytes were pretreated with IFN-γ, they could promote the proliferation and secretion levels of MOG(35-55) -specific lymphocytes, coinciding with apparent expression of major histocompatibility complex (MHC)-II on astrocytes themselves. Quantitative polymerase chain reaction (qPCR) demonstrated that production of IL-27 in the spinal cord was at its highest during the initial phases. Conversely, production of IFN-γ in the spinal cord was highest during the peak phase. Quantitative analysis of MHC-II expression in the spinal cord showed that there was a positive correlation between MHC-II expression and IFN-γ production. In addition, astrocyte MHC-II expression levels correlated positively with IFN-γ production in the spinal cord. These findings suggested that astrocytes might function as both inhibitors and promoters of EAE. Astrocytes prevented MOG(35-55) -specific lymphocyte function by secreting IL-27 during the initial phases of EAE. Then, in the presence of higher IFN-γ levels in the spinal cord, astrocytes were converted into antigen-presenting cells. This conversion might promote the progression of pathological damage and result in a peak of EAE severity.

[Research on the quantitative determination of lime in wheat flour by near-infrared spectroscopy]

The safety of wheat flour is always focused by all quarters of society. Based on comparing the feature of NIR spectra of calcium oxide, calcium hydroxide and calcium carbonate in this research, the diffuse reflection NIR spectra of the wheat flour samples with different content of calcium oxide, calcium hydroxide and calcium carbonate mixed in were collected. The calibration models of lime and calcium carbonate were developed by partial least square algorithm, with the validation method of cross validation. The result indicated that the determination coefficients (R2) of lime and calcium carbonate are 99.80% and 96.98% respectively, the root mean square errors of calibration set are 0.19 and 0.34 respectively; the root mean square errors of cross validation set are 0.26 and 0.75 respectively; the root mean square errors of prediction set are 0.63 and 0.44 respectively; the ratio performance deviations (RPD) are 8.57 and 5.24 respectively, which indicated that the calibration models were precise enough to adapt to the on-site rapid determination of lime in wheat flour. The result of F-test indicated that a very remarkable correlation exists between the estimated and specified values of the calibration sets and the external validation sets. This research, to some extent, will provide some reference methods for the rapid determination of wheat flour for quality safety, which is important for the quality control of wheat flour.

[Hyperspectral estimation of leaf water content for winter wheat based on grey relational analysis (GRA)]

The objective of the present study was to compare two methods for the precision of estimating leaf water content (LWC) in winter wheat by combining stepwise regression method and partial least squares (SRM-PLS) or PLS based on the relational degree of grey relational analysis (GRA) between water vegetation indexes (WVIs) and LWC. Firstly, data utilized to analyze the grey relationships between LWC and the selected typical WVIs were used to determine the sensitivity of different WVIs to LWC. Secondly, the two methods of estimating LWC in winter wheat were compared, one was to directly use PLS and the other was to combine SRM and PLS, and then the method with the highest determination coefficient (R2) and lowest root mean square error (RMSE) was selected to estimate LWC in winter wheat. The results showed that the relationships between the first five WVI and LWC were stable by using GRA, and then LWC was estimated by using PLS and SRM-PLS at the whole stages with the R2 and RMSEs being 0.605 and 0.575, 4.75% and 7.35%, respectively. The results indicated that the estimation accuracy of LWC could be improved by using GRA firstly and then by using PLS and SRM-PLS.

[Sorption and desorption of 17alpha-ethinyl estradiol and 4-n-nonylphenol in soil]

The sorption kinetics and sorption/desorption isotherms of two endocrine disrupting chemicals (EDCs) including 17alpha-ethinyl estradiol (EE2) and 4-n-nonylphenol (NP) on three natural soils with different physicochemical properties were investigated. Results showed that two-compartment first-order model performed better than one-compartment first-order model in description of EDCs' kinetic sorption. The fast sorption compartment was dominant in the initial stage, and then contribution from slow sorption compartment increased gradually with time until equilibrium. The adsorption rate of EE2 was 2.0-4.7 times as that of NP. For adsorption isotherms, both Freundlich and Dubinin-Ashtakhov (DA) models provided good fit, though DA model was more appropriate. The saturated sorption capacity (Q0) was in a positive correlation to the content of soil organic matter, and higher Q0 was found for NP (10.47-110.15 microg x g(-1)) than EE2 (0.85-7.67 microg x g(-1)). The calculated free energy of sorption indicated that physical process dominated sorption of EE2 and NP in soil. The desorption hysteresis occurred in sorption/desorption experiments of EE2 and NP, especially in soils with the high organic matter fraction and large specific surface, indicating EDCs' potential environmental risk in soil.

Fundamental denitrification kinetic studies with Pseudomonas denitrificans

Fundamental kinetic studies on the reduction of nitrate, nitrite, and their mixtures were performed with a strain of Pseudomonas denitrificans (ATCC 13867). Methanol served as the carbon source and was supplied in excess (2:1 mole ratio relative to nitrate and/or nitrite). Nitrate and nitrite served as terminal electron acceptors as well as sources of nitrogen for biomass synthesis. The results were explained under the assumption that respiration is a growth-associated process. It was found that the sequence of complete reduction of nitrate to nitrogen gas is via nitrite and nitrous oxide.It was found that the specific growth rate of the biomass on either nitrate or nitrite follows Andrews inhibitory kinetics and nitrite is more inhibitory than nitrate. It was also found that the culture has severe maintenance requirements which can be described by Herbert's model, i.e., by self-oxidation of portions of the biomass. The specific maintenance rates at 30 degrees C and pH 7.1 were found to be equal to about 28% of the maximum specific growth rate on nitrate and 23% of the maximum specific growth rate on nitrite. Nitrate and nitrite were found to be involved in a cross-inhibitory noncompetitive kinetic interaction. The extent of this interaction is negligible when the presence of nitrite is low but is considerable when nitrite is present at levels above 15 mg/L.Studies on the effect of temperature have shown that the culture cannot grow at temperatures above 40 degrees C. The optimal temperature for nitrate or nitrite reduction was found to be about 38 degrees C. Using an Arrhenius expression to describe the effect of temperature on the specific growth rates, it was found that the activation energy for the use of nitrate by the culture is 8.6 kcal/mol and 7.21 kcal/mol for nitrite. Arrhenius-type expressions were also used in describing the effect of temperature on each of the parameters appearing in the specific growth rate expressions. Studies on the effect of pH at 30 degrees C have shown that the culture reduces nitrate optimally at a pH between 7.4 and 7.6, and nitrite at a pH between 7.2 and 7.3. (c) 1995 John Wiley & Sons, Inc.

[Laser-induced fluorescence spectroscopy characterization of farmland soil moisture content]

Online measurement of soil moisture is significant for agricultural production. The abundance and deficiency of leaf water shortage has been able to effect measured by fluorescence, but the research of correlation between soil moisture and laser-induced fluorescence spectroscopy has not been carried out yet. In this paper, the relationship between laser-induced plant chlorophyll fluorescence and soil moisture was studied. In the experiment with rice as the research object, the chlorophyll fluorescence induced by a 450 nm LED light source was measured by a Y-shaped fiber probe, and the soil moisture was obtained by TDR sensors. The changes in the peak intensity near 743 nm of chlorophyll fluorescence under continuous water stress and intermittent water stress were studied. The result showed that the intensity decreased with the soil moisture content. Finally, the model between the soil water content and the intensity of chlorophyll fluorescence under continuous water stress was created by using Lorentzian equation, and the coefficient of determination (R2) of the model was high. The result indicated that the method mentioned in paper can be applied to measure soil moisture in agricultural production.

Serum prolactin levels and the acute-phase efficacy in drug-naïve schizophrenia treated with ziprasidone and olanzapine (translated version)

OBJECTIVES. To study the efficacy and associated serum prolactin levels of ziprasidone and olanzapine treatment in drug-naïve schizophrenia patients. METHODS. All 78 inpatients with drug-naïve schizophrenia were recruited from the Department of Psychology, The Third Affiliated Hospital of Sun Yat-sen University. They were divided into either olanzapine group (n = 49 [24 men, 25 women]; mean [standard deviation] age, 24 [6] years) or ziprasidone group (n = 29 [14 men, 15 women]; mean [standard deviation] age, 23 [7] years), all of whom were treated for 4 weeks. The serum prolactin level, the Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression-Severity (CGI-S), and Clinical Global Impression-Improvement scores were measured before and at the end of treatment. RESULTS. In the olanzapine group, the respective mean (standard deviation) PANSS and CGI-S scores after the treatment (62 ± 15 and 3 ± 1) were significantly lower than those before the treatment (104 ± 14 and 6 ± 1) [p < 0.01]. In the ziprasidone group, the corresponding scores after the treatment (75 ± 20 and 4 ± 1) were also significantly lower than those before the treatment (104 ± 17 and 6 ± 1) [p < 0.01]. The decreases in mean (standard deviation) PANSS total (42 ± 17) and PANSS positive scores (12 ± 6) in the olanzapine group were significantly higher than those in the ziprasidone group (29 ± 12 and 6 ± 4, respectively) [p < 0.01]. The increase of serum prolactin in the ziprasidone female group (47 ± 51 µg/L) was significantly higher than that in the ziprasidone male group (17 ± 11 µg/L), the olanzapine male group (5 ± 16 µg/L), and the olanzapine female group (21 ± 34 µg/L) [p < 0.05]. CONCLUSIONS. Both ziprasidone and olanzapine are effective for treating drug-naïve acute schizophrenia, but olanzapine was superior to ziprasidone in terms of positive and general psychopathological symptoms. In women, ziprasidone was associated with greater changes in prolactin level than olanzapine.

QM/MM studies on the catalytic mechanism of phenylethanolamine N-methyltransferase

Epinephrine is a naturally occurring adrenomedullary hormone that transduces environmental stressors into cardiovascular actions. As the only route in the catecholamine biosynthetic pathway, Phenylethanolamine N-methyltransferase (PNMT) catalyzes the synthesis of epinephrine. To elucidate the detailed mechanism of enzymatic catalysis of PNMT, combined quantum-mechanical/molecular-mechanical (QM/MM) calculations were performed. The calculation results reveal that this catalysis contains three elementary steps: the deprotonation of protonated norepinphrine, the methyl transferring step and deprotonation of the methylated norepinphrine. The methyl transferring step was proved to be the rate-determining step undergoing a SN2 mechanism with an energy barrier of 16.4kcal/mol. During the whole catalysis, two glutamic acids Glu185 and Glu219 were proved to be loaded with different effects according to the calculations results of the mutants. These calculation results can be used to explain the experimental observations and make a good complementarity for the previous QM study.

Fabrication of large scale nanostructures based on a modified atomic force microscope nanomechanical machining system

The atomic force microscope (AFM) tip-based nanomechanical machining has been demonstrated to be a powerful tool for fabricating complex 2D∕3D nanostructures. But the machining scale is very small, which holds back this technique severely. How to enlarge the machining scale is always a major concern for the researches. In the present study, a modified AFM tip-based nanomechanical machining system is established through combination of a high precision X-Y stage with the moving range of 100 mm × 100 mm and a commercial AFM in order to enlarge the machining scale. It is found that the tracing property of the AFM system is feasible for large scale machining by controlling the constant normal load. Effects of the machining parameters including the machining direction and the tip geometry on the uniform machined depth with a large scale are evaluated. Consequently, a new tip trace and an increasing load scheme are presented to achieve a uniform machined depth. Finally, a polymer nanoline array with the dimensions of 1 mm × 0.7 mm, the line density of 1000 lines/mm and the average machined depth of 150 nm, and a 20 × 20 polymer square holes array with the scale of 380 μm × 380 μm and the average machined depth of 250 nm are machined successfully. The uniform of the machined depths for all the nanostructures is acceptable. Therefore, it is verified that the AFM tip-based nanomechanical machining method can be used to machine millimeter scale nanostructures.

In vitro rumen fermentation and methane production are influenced by active components of essential oils combined with fumarate

Two trials were conducted to identify the optimal levels of essential oil active components (EOAC) and their combination with fumarate on in vitro rumen fermentation. In trial 1, eugenol, carvacrol, citral and cinnamaldehyde were mixed at ratios of 1:2:3:4, 2:1:4:3, 3:4:1:2, 4:3:2:1 and 1:1:1:1 to make up five combinations (EOAC1, EOAC2, EOAC3, EOAC4 and EOAC5 respectively). The mixtures were supplied at levels of 0, 50, 200 or 500 mg/l to identify the optimal combination for methane reduction. Methane production and ammonia nitrogen were decreased by adding EOAC, irrespective of component compounds, but the production of gas and total volatile fatty acids (VFA) were also decreased. Hydrogen balance analysis indicated that the ratio of hydrogen consumed via methane to hydrogen consumed via VFA was lowest at 200 mg/l of EOAC5 treatment, from which the proportional change in methane was more than the change in VFA, with 31.5% of methane reduction and 12.9% of VFA reduction. In trial 2, 200 mg/l of EOAC5 was added with 0, 5, 10 and 15 mm monosodium fumarate to see whether fumarate had a further effect on rumen fermentation. The addition of fumarate had no influence on gas production, but it further decreased methane and increased the total VFA in comparison with EOAC added solely, with the greatest decrease occurring in methane (78.1%) from 10 mm of fumarate. Quantification of the microbial populations in rumen fluids by RT-PCR showed that methanogen, protozoa, fungi, Fibrobacter succinogenes and Ruminococcus flavefaciens populations were significantly decreased by EOAC5, but were not influenced by fumarate. In summary, the addition of EOAC had consistent effects on rumen fermentation parameters, but high levels of EOAC would induce the inhibition of rumen fermentation. Adding fumarate can enhance the methane-inhibiting effect of EOAC, and the decrease was higher than that calculated stoichiometrically.

Receptor-based QSAR study for a series of 3,3-disubstituted-5-aryl oxindoles and 6-aryl benzimidazol-2-ones derivatives as progesterone receptor inhibitors

Receptor-based comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were performed on a series of 54 progesterone receptor (PR) inhibitors. The established CoMFA model from the training set gives statistically significant results with the cross-validated q (2) of 0.534 and non-cross-validated [Formula: see text] of 0.947. The best CoMSIA model was derived by the combination of steric field and hydrophobic field with a q (2) of 0.615 and [Formula: see text] of 0.954. A test set of 18 compounds was used to validate the predictive ability of the two models. The predicted correlation coefficients [Formula: see text] are 0.681 and 0.677 for CoMFA and CoMSIA models, respectively. Based on the CoMFA maps, the key structural characters of progesterone receptor inhibitors are identified. Moreover, the binding modes of oxindoles and benzimidazol-2-ones are also given by the quantum mechanical/molecular mechanical (QM/MM) calculations. This may provide useful information for drug design.

An integrative method for identifying the over-annotated protein-coding genes in microbial genomes

The falsely annotated protein-coding genes have been deemed one of the major causes accounting for the annotating errors in public databases. Although many filtering approaches have been designed for the over-annotated protein-coding genes, some are questionable due to the resultant increase in false negative. Furthermore, there is no webserver or software specifically devised for the problem of over-annotation. In this study, we propose an integrative algorithm for detecting the over-annotated protein-coding genes in microorganisms. Overall, an average accuracy of 99.94% is achieved over 61 microbial genomes. The extremely high accuracy indicates that the presented algorithm is efficient to differentiate the protein-coding genes from the non-coding open reading frames. Abundant analyses show that the predicting results are reliable and the integrative algorithm is robust and convenient. Our analysis also indicates that the over-annotated protein-coding genes can cause the false positive of horizontal gene transfers detection. The webserver of the proposed algorithm can be freely accessible from www.cbi.seu.edu.cn/RPGM.

[FTIR microspectroscopy and its progress in application]

FTIR microspectroscopy technique was born in the mid-nineties. The research on this technique has just began abroad, and this technology has not yet been widely recognized in China. It is a rapid, nondestructive testing technology, has the advantages of microdomain, visualization, high precision and high sensitivity. In the present study, the composition, operational principle and working mode of FTIR microspectroscopy were summarized. The progress in application of FTIR microspectroscopy technique was investigated in some fields, including biomedicine, microbiology, forensic science, materials science, nutrition and feed science and agricultural products. The difficulty of FTIR microspectroscopy research and the prospects of this technique were also discussed.

[Comparative research on the NIR and MIR micro-imaging of two similar plastic materials]

The NIR/MIR micro-imaging can supply not only the information of spectra, but also the information of spacial distribution of the sample, which is superior to the traditional NIR/MIR spectroscopy analysis. In the present paper, polyethylene and parafilm, with similar appearances, were regarded as the research objects, of which the NIR/MIR micro-imaging was collected. Chemical imaging (CI) and compare correlation imaging were carried out for the two materials respectively to discuss the imaging methods of the two materials. The result indicated that the differentiation of the CI values of the two materials in the NIR/MIR CI for material II was 0.004 8 and 0.254 8 respectively, while those in the NIR/MIR CI for material I were 0.002 6 and 0.326 5, respectively. Clear CI was acquired, and the two materials could be differentiated. The result of the compare correlation imagings indicated that the compare correlation imagings, in which the NIR/MIR spectra of the two materials were regarded as reference spectra respectively, can differentiate the two materials remarkably with clear imagings. In the compare correlation imagings of MIR micro-imaging, the difference of the correlation coefficients between the two materials' MIR spectra and the reference spectrum was more than 0.12, which showed a better imaging result; while a tiny difference of the correlation coefficients between the two materials' NIR spectra and the reference spectrum could be employed to show a clear imaging result for NIR compare correlation imaging so as to differentiate the two materials. This thesis, to some extent, can supply the reference to not only the rapid discrimination of the safety of the packaging material for agri-food, but also the imaging methods for NIR/MIR micro-imaging to differentiate the different materials.

Local characteristics of cross-unit contamination around high-rise building due to wind effect: mean concentration and infection risk assessment

In this present work, the characteristics of hazardous gas dispersion and possible cross-unit contamination around a complex-shaped high-rise residential building due to wind effect are thoroughly studied using physical modeling method. Experiments were performed in a boundary layer wind tunnel for a 1:30 scale model that represented a 10-story residential building in prototype. Tracer gas, simulating exhausted room air, was continuously released from different floor levels, and its concentrations on the adjacent envelope surfaces were measured using fast flame ionization detectors. The mean concentration fields were reported and analyzed under different configurations during the experiment to consider the effects on pollutant dispersion behavior due to changes in source position and approaching wind condition, with the main emphasis on the differences between open-window and closed-window conditions. In particular, the measured concentration fields were further examined from a practical point of view, with respect to hazard assessment. Understanding these hazardous plume dispersion features is useful for employing effective intervention strategies in modern residential building environment in case of hazardous substance release. The study on this physical process is not only helpful to reduce the hazardous effect of routine release of harmful pollutant near the building, but also useful for the purpose of prevention and control of accidental infectious diseases outbreak.

Local characteristics of cross-unit contamination around high-rise building due to wind effect: mean concentration and infection risk assessment

In this present work, the characteristics of hazardous gas dispersion and possible cross-unit contamination around a complex-shaped high-rise residential building due to wind effect are thoroughly studied using physical modeling method. Experiments were performed in a boundary layer wind tunnel for a 1:30 scale model that represented a 10-story residential building in prototype. Tracer gas, simulating exhausted room air, was continuously released from different floor levels, and its concentrations on the adjacent envelope surfaces were measured using fast flame ionization detectors. The mean concentration fields were reported and analyzed under different configurations during the experiment to consider the effects on pollutant dispersion behavior due to changes in source position and approaching wind condition, with the main emphasis on the differences between open-window and closed-window conditions. In particular, the measured concentration fields were further examined from a practical point of view, with respect to hazard assessment. Understanding these hazardous plume dispersion features is useful for employing effective intervention strategies in modern residential building environment in case of hazardous substance release. The study on this physical process is not only helpful to reduce the hazardous effect of routine release of harmful pollutant near the building, but also useful for the purpose of prevention and control of accidental infectious diseases outbreak.

[Investigation of the hyperspectral image characteristics of wheat leaves under different stress]

The diagnosis of growing status and vigor of crops under various stresses is an important step in precision agriculture. Hyperspectral imaging technology has the advantage of providing both spectral and spatial information simultaneously, and has become a research hot spot. In the present study, auto-development of the pushbroom imaging spectrometer (PIS) was utilized to collect hyperspectral images of wheat leaves which suffer from shortage of nutrient, pest and disease stress. The hyperspectral cube was processed by the method of pixel average step by step to highlight the spectral characteristics, which facilitate the analysis based on the differences of leaves reflectance. The results showed that the hyperspectra of leaves from different layers can display nutrient differences, and recognize intuitively different stress extent by imaging figures. With the 2 nanometer spectral resolution and millimeter level spatial resolution of PIS, the number of disease spot can be qualitatively calculated when crop is infected with diseases, and, the area of plant disease could also be quantitatively analyzed; when crop suffered from pest and insect, the spectral information of leaves with single aphid and aphids can be detected by PIS, which provides a new means to quantitatively detect the aphid destroying of wheat leaf. The present study demonstrated that hyperspecral imaging has a great potential in quantitative and qualitative analysis of crop growth.

A novel sheep vertebral bone defect model for injectable bioactive vertebral augmentation materials

New injectable bone substitutes have been developed that are, unlike polymethylmethacrylate, biologically active and have an osteogenic effect leading to osteogenesis and bone remodeling for vertebroplasty or kyphoplasty. In this study, we developed a sheep vertebral bone defect model to evaluate the new bioactive materials and assessed the feasibility of the model in vivo. Bone voids were experimentally created on lumbar vertebrae L2-L5 with L1 and L6 left intact as a normal control in mature sheep. The defect vertebrae L2-L5 in each sheep were randomized to receive augmentation with calcium phosphate cement (CPC) or sham. Vertebrae (L1-L6) were collected after 2 and 24 weeks of the cement augmentation and their strength and stiffness, as well as osseointegration activity and biodegradability, were evaluated. Finally, CPC significantly improved the strength and stiffness of vertebrae but did not yet restore it to the normal level at 24 weeks. Osteogenesis occurred at a substantially high level after 24 weeks of CPC augmentation or sham. Therefore, the sheep vertebral model with one void, 6.0 mm in diameter and 15.0 mm in depth, is replicable and can be used for evaluating the new injectable bioactive materials in vertebral augmentation or reconstruction.

[Study on relationship between new characteristic parameters of spectral curve and chlorophyll content for rice]

It is of significance to monitor chlorophyll content with hyperspectral data for crop growth diagnosis in field. In the study, with the point of view that spectral curve shapes display "tall, low, fat and thin" morphological changes, we proposed some new characteristic parameters from spectral curve such as the ascensive or degressive velocities of segments composing peak or valley shapes in spectral curve, and angles formed by the lines fitting the segments of two sides of peak or valley curves, and used the normalized spectra to analyze correlation between these parameters and rice chlorophyll content. The result shows that (1) there is a good negative correlation between rice chlorophyll content and normalized reflectance spectra from 520-740 nm; (2) characteristic parameters from green peak region of spectral curve display better correlation with rice chlorophyll content, which makes it possible to utilize the parameters to monitor crop chlorophyll content, and will provide new ideas and methods for carrying out crop growth diagnosis with hyperspectral data.

Effect of different rumen-inert fatty acids supplemented with a dietary antioxidant on performance and antioxidative status of early-lactation cows

The objective of the study was to evaluate the effect of diets supplemented with fatty acids of different degrees of saturation, in the absence or presence of an antioxidant (AOX; Agrado Plus, Novus International Inc., St. Charles, MO), on dairy cow lactation performance. Calcium salts of long-chain fatty acids were supplemented as a source of lower saturation fatty acid, and a palm acid product was supplemented as the higher saturation fatty acid source. Sixty early-lactation Chinese Holstein cows (100+/-23 d in milk) were randomly allocated to 4 dietary treatments in a 2 x 2 factorial design: (1) lower saturation fatty acid (LS), (2) LS and AOX, (3) higher saturation fatty acid (HS), and (4) HS and AOX. The Ca salts of long-chain fatty acids and palm acid product were supplied at 1.8 and 1.5% on a dry matter basis, respectively, to form isoenergetic diets. The AOX was added at 0.025% in the ration. The experiment lasted 9 wk, including 1 wk for adaptation. Lactation performance was recorded and milk was sampled and analyzed weekly. Blood samples were taken from the coccygeal vein to determine metabolism parameters on d 16, 36, and 56 during the experiment. Neither fatty acid type nor AOX supplementation showed a significant effect on dry matter intake during the study. Milk yield was lower in the LS-fed cows compared with the cows fed HS. Milk fat and milk protein concentrations were not affected by fatty acid type or AOX supplementation. Adding AOX increased the yield of milk in the LS-fed cows, but did not affect those fed HS. Activity of plasma superoxide dismutase was significantly lower, plasma glucose tended to be lower, and plasma malondialdehyde was higher in the LS-fed animals compared with those fed HS. Addition of AOX decreased both plasma nonesterified fatty acids and hydrogen peroxide contents and increased total antioxidant capacity across the fatty acid types. Plasma beta-hydroxybutyrate was not affected by fatty acid type or AOX treatment. Cows fed LS had higher cis-9C(18:1) and trans-10, cis-12C(18:2) in milk at the expense of C(18:0), whereas AOX addition increased milk cis-9C(18:1) at the expense of milk C(12:0), C(16:0), and trans-10, cis-12C(18:2). It is inferred that feeding LS resulted in inferior lactation performance, whereas addition of antioxidant partially alleviated these negative effects.

First Report of Phytophthora Blight of Lily Caused by Phytophthora nicotianae in China

Lily (Lilium spp.) is an economically important cut flower in China. In August 2009, 30 to 40% of plants of lily cv. Siberia in a greenhouse for cut flower production in Yunnan, China were severely diseased. Infected plants developed water-soaked lesions and soft rot on the base of stems and leaves near the soil surface. As the disease progressed, stems bent and plants collapsed. Soft rot symptoms were observed on some bulbs and roots of severely diseased plants. Small, diseased tissue fragments (approximately 3 mm) were surface disinfected with 0.5% NaOCl and then plated to Phytophthora selective medium (10% V8 juice agar) (4). Inoculated dishes were incubated at 25°C in the dark. After 5 days, white colonies with abundant aerial mycelia developed from all plated tissue samples. The fungus had aseptate hyphae. Sporangia were papillate, both caducous and noncaducous, and the shape ranged from ovoid to spherical. The dimensions of sporangia were 30 to 62 × 21 to 46 μm. On the basis of morphological features, isolates were identified as Phytophthora nicotianae Breda de Haan. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS1/ITS4 and sequenced. BLAST analysis of the 835-bp fragment showed a 99% homology with the sequence of P. nicotianae AY833527. The nucleotide sequence has been assigned GenBank No. GU299778. PCR amplification of genomic DNAs using the P. nicotianae-specific primer pair ITS3-PNIC1 generated a 455-bp sequence (3). The result further confirmed the identity of P. nicotianae. Pathogenicity tests were conducted in the greenhouse on lily cv. Siberia grown in pots. Ten 3-month-old plantlets were inoculated by watering the wounded stem bases and soil surface with 30 ml of zoospore suspensions (10⁵ spores per ml). Five uninoculated plantlets were used as controls. All plantlets were covered with plastic bags and incubated at room temperature (22 to 26°C) for 48 h. Inoculated plants developed initial symptoms of slight chlorosis and wilting of lower leaves. Within a 3-week period, all plants died due to soft rot of stem bases and leaves. The pathogen was reisolated from inoculated plants but not from control plants that were symptomless. P. nicotianae has been reported as the causal agent of Phytophthora blight on lily in Korea, Japan, and Hungary (1,2). To our knowledge, this is the first report of Phytophthora blight of lily in China. References: (1) J. Bakonyi et al. Plant Pathol. 50:795, 2001. (2) H. J. Jee and W. G. Kim. Plant Pathol. J. 14:452, 1998. (3) P. W. Tooley et al. Appl. Environ. Microbiol. 63:1467, 1997. (4) X. B. Zheng. Phytophthora and Its Research Technology. Beijing. China Agriculture Press, Beijing, 1997.

[Monitoring of winter wheat stripe rust based on the spectral knowledge base for TM images]

In most cases, the reversion model for monitoring the severity degree of stripe rust based on the hyperspectral information can not be directly applied by the satellite images with relatively broad bandwidth, while the airborne hyperspectral images can not be applied for large-scale monitoring either, due to the scale limitation of its data and high cost. For resolving this dilemma, we developed a monitoring method based on PHI images, which relies on the construction of spectral knowledge base of winter wheat stripe rust. Three PHI images corresponding to the winter wheat experimental field that included different severity degree of stripe rust were used as a medium to establish the spectral knowledge base of relationships between disease index (DI) and the simulated reflectance of TM bands by using the empirical reversion model of DI(%) and the relative spectral response (RSR) function of TM-5 sensor. Based on this, we can monitor and identify the winter wheat stripe rust by matching the spectral information of an untested pixel to the spectral knowledge base via Mahalanobis distance or spectral angle mapping (SAM). The precision of monitoring was validated by simulated TM pixels, while the effectiveness of identification was tested by pixels from TM images. The results showed that the method can provide high precision for monitoring and reasonable accuracy for identification in some certain growth stages of winter wheat. Based on the simulated TM pixels, the model performed best in the pustulation period, yielded a coefficient of determination R2 = 0.93, while the precision of estimates dropped in the milk stage, and performed worst in the jointing stage, which is basically inappropriate for monitoring. Moreover, by using the pixels from TM images, the infected pixels could be identified accurately in pustulation and milk stages, while failed to be identified in jointing stage. For matching algorithms, the Mahalanobis distance method produced a slightly better result than SAM method.

First Report of Neofusicoccum parvum Causing Dieback Disease of Chinese Weeping Cypress in China

Cupressus funebris Endl. (Chinese weeping cypress) is native to southwestern and central China. In June 2008, blighted shoots of Chinese weeping cypress trees were observed in Yunnan Province (southwestern China). Symptomatic trees were located in an ornamental planting established approximately 8 to 12 years ago. Additional samples were collected from 11 locations in the provinces of Sichuan, Yunnan, Guizhou, and Chongqing. Disease symptoms included yellowing and wilting of leaves on several branches, followed by sudden death within 6 to 8 weeks. Cross sections on trunks and branches revealed darkened zones. Tissue from diseased samples was plated on potato dextrose agar (PDA) and incubated at 25°C. Fungal isolates developed copious, white, aerial mycelium that became dark gray after 4 to 6 days and formed black pycnidia after 25 days. Conidia were hyaline, ellipsoidal to fusiform, externally smooth, thin walled, nonseptate, and measured 12.5 to 18.5 × 4.0 to 6.5 μm. Identity was confirmed by analysis of the rDNA internal transcribed spacer region (ITSI-5.8S-ITS2) and the translation elongation factor 1-alpha (EF1-α). BLAST searches at GenBank showed a high identity with reference sequences (ITS: >99%; EF1-α: 100%). Representative sequences of both regions were deposited in GenBank (ITS: Accession No. FJ842960 and FJ842961; EF1-α: Accession No. GU811148). Morphological and molecular results confirmed this species as Neofusicoccum parvum, reported as the anamorph of Botryosphaeria parva. Pathogenicity tests were conducted by stem inoculation of 2-year-old C. funebris seedlings. Mycelial plugs (4 mm in diameter) of N. parvum from actively growing colonies were applied to same-size bark wounds on the middle point of the stems. Control seedlings were inoculated with sterile PDA plugs. Inoculated and control seedlings (five each) were kept in a greenhouse and watered as needed. After 5 weeks, all C. funebris seedlings showed leaf wilting and dark vascular stem tissue. N. parvum was reisolated from all inoculated, symptomatic tissues, fulfilling Koch's postulates; no symptoms were visible in the control seedlings. N. parvum has previously been reported to cause canker and dieback disease of avocado (3), mango (2), and magenta cherry (Syzygium paniculatum) (1). To our knowledge, this is the first report of N. parvum causing dieback of C. funebris in China. References: (1) R. C. Ploetz et al. Plant Pathol. 58:801, 2009. (2) B. Slippers et al. Mycologia 97:99, 2005. (3) T. Zea-Bonilla et al. Plant Dis. 91:1052, 2007.

rtE218G, a novel hepatitis B virus mutation with resistance to adefovir dipivoxil in patients with chronic hepatitis B

Antiviral therapy is a potentially successful approach for the treatment of patients with Hepatitis B virus (HBV) infection. One antiviral agent is the nucleoside analogue adefovir dipivoxil (ADV). Its efficiency is compromised by the emergence of drug-resistant HBV mutants. Although three major ADV-resistant mutations of HBV are known, rtA181T/V and rtN236T, HBV mutations associated with ADV resistance have not been fully identified. We analyzed DNA sequences that covered a 244 base pair region of the HBV polymerase gene from patients with clinical manifestations of ADV resistance. A novel pattern of amino acid substitutions in HBV polymerase was detected in 26 out of 86 patients. This mutant exhibited a substitution of glycine for glutamic acid at residue 218 (rtE218G). Transient transfection of the HBV replication-competent construct including the rtE218G mutation was performed in HepG2 cells in order to determine the relevance of this mutation to ADV resistance. Phenotypic analyses demonstrated that the rtE218G mutation could independently confer resistance to ADV in vitro, with a 50% inhibitory concentration (IC(50)) 5.5-fold higher than wild-type HBV. RtE218G-mutated HBV also showed a decreased replication capacity in vitro, equal to 87% of wild-type HBV. The present study showed that the rtE218G mutation may be a novel ADV-resistant mutation. Further work will focus on resistance surveillance and cross-resistance analyses, and the molecular mechanisms involved.

Regulatory T cells in chronic hepatitis B patients affect the immunopathogenesis of hepatocellular carcinoma by suppressing the anti-tumour immune responses

Chronic hepatitis B (CHB) virus hepatitis B virus (HBV) infection is the key cause of hepatocellular carcinoma (HCC) in Asians. Recent studies have shown that levels of CD4(+)CD25(+) regulatory T cells (Tregs) were increased and were linked to an impaired immune response in patients with CHB. Evaluating whether Tregs are involved in the progression of CHB to HCC will provide insight into the immunopathogenesis of HCC. In the present study, we showed that circulating and liver-residing Tregs increased in CHB (n = 15) and HCC (n = 49) patients, particularly in the peripheral blood of HCC patients with HBV infection (n = 29). The increased Tregs in CHB patients suppressed the specific immune response induced by not only HBV antigen, but also by HCC tumour antigen. When peripheral blood mononuclear cells (PBMC) were co-cultured with human hepatoma cell lines that are stably transfected with HBV (HepG2.2.15), CD4(+)CD25(+) Treg populations increased and upregulated the expression of forkhead box P3 transcriptional regulator (FoxP3), cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and glucocorticoid-induced tumour necrosis factor (TNF) receptor family gene (GITR). In contrast, PBMCs co-cultured with HepG2 cells (the parental cell line of HepG2.2.15) did not. CD4(+)CD25(+) Tregs isolated from PBMCs that were co-cultured with HepG2.2.15 cells also had a greater suppressive ability with respect to the tumour antigen-specific immune response induced by NY-ESO-1 or MAGE-A3 compared with CD4(+)CD25(+) Tregs isolated from PBMCs co-cultured with HepG2 cells. The results offer evidence that the expansion of CD4(+)CD25(+) Tregs and the enhancement of the suppressor function of CD4(+)CD25(+) Tregs induced by HBV infection-related factors could suppress the anti-tumour immune response to HCC tumour antigen and inhibit tumour immuno-surveillance against HCC, which may be involved in the immunopathogenesis from CHB to HCC.

[New index for crop canopy fresh biomass estimation]

The objective of the present study is to propose a new vegetation index for corn canopy fresh biomass estimation, which improves the ability to accurately estimate high biomass levels by remote sensing technology. For this purpose, hyperspectral reflectance data of corn canopies were collected using a ground-based spectroradiometer during different field campaigns in a region of Quebec (Canada), from 2004 to 2008. Corresponding fresh biomass values were obtained by destructive measurements, and a hyperspectral image was also acquired using the Compact Airborne Spectrographic Imager (CASI) in 2005. A new biomass index named red-edge triangular vegetation index (RTVI) was designed and compared to existing indices used for fresh biomass estimation. The results showed that RTVI was the best vegetation index for predicting canopy fresh biomass, with sustained sensitivity at high fresh biomass levels. The best regression model between RTVI and canopy fresh biomass was the power fit, with determination coefficient (R2) of 0.96. With the validation by CASI imagery in 2005, good results were obtained. The relationship between CASI predicted biomass and actual biomass was 0.58 (R2), with the RMSE of 0.44 kg x m(-2).

First Report of Pyricularia grisea Causing Gray Leaf Spot on Lily in Korea

Lily is an economically important ornamental crop in Korea. In August 2008, severe leaf spot symptoms were observed on an oriental Lily 'Action' in a plant nursery in Daegu, Korea. Disease incidence was 20 to 30%. Initial symptoms were olive green-to-brown lesions on the leaf that developed into tan, elliptical, necrotic lesions. On severely infected leaves, lesions coalesced and killed the entire leaf blade. Infected leaves were surface disinfested with 70% ethanol for 30 s and 2% chlorox for 15 min before plating 1 cm² sections onto potato dextrose agar. Hyphae appeared 5 days after inoculation and pure culture. Conidia were hyaline, transversely septate with one to three septa; most had two. Conidia were obpyriform and measured 29 to 46 μm long and 7 to 17 μm wide. Mycelia morphology and conidia production were consistent with that described previously for Pyricularia grisea (1). Koch's postulates were fulfilled by spraying five, healthy, vegetative-stage plants with 2 × 10⁵ conidia per ml of sterile distilled water plus 0.05% Tween 20. As a control, five similar plants were sprayed with sterile water plus 0.05% Tween 20 only. Plants were placed inside plastic bags to maintain high relative humidity and incubated in a growth chamber at 25°C under fluorescent light for 14 h and at 20°C in darkness for 10 h. After 3 days, the plastic bags were removed and plants were maintained under the same conditions. Initial symptoms were observed 7 days after inoculation. Ten days after inoculation, disease symptoms on inoculated plants were similar to those previously described in the nursery. Control plants did not show any symptoms. Fungi isolated from these lesions had the same morphological characteristics as the ones isolated previously from plants in the nursery. To our knowledge, this is the first report of gray leaf spot on lily caused by P. grisea in Korea. References: (1) M. B. Ellis. Dematiaceous Hyphomycetes. CMI, Kew, Surrey, UK, 1971.

Pharmacological studies on the sedative-hypnotic effect of Semen Ziziphi spinosae (Suanzaoren) and Radix et Rhizoma Salviae miltiorrhizae (Danshen) extracts and the synergistic effect of their combinations

Semen Ziziphi spinosae (Suanzaoren in China) and Radix et Rhizoma Salviae miltiorrhizae (Danshen in China) are conventional herbal drugs in traditional Chinese medicine and have been used widely for the treatment of insomnia. In the present study, the sedative-hypnotic activity of the active fractions extracted from Suanzaoren and Danshen were studied using the method of pentobarbital-induced sleep in the mouse model. Qualitative analysis of the standardized extracts was carried out by HPLC-DAD. The results showed that the water extract of Suanzaoren (SWE) (400 and 800 mg/kg body wt.) and the ether extract of Danshen (DTT) (300 and 600 mg/kg body wt.) can shorten sleep latency significantly, increase sleeping time and prolong movement convalescence time induced by sodium pentobarbital (55 mg/kg body wt.) administration in mice. Furthermore, the combination of SWE and DTT showed significant synergistic effect (p<0.05) in decreasing sleep latency and increasing sleeping time, but not in prolonging the movement convalescence time, which might be helpful for energy recovery in the treatment of insomnia. The results suggest that SWE, DTT, and the combination of SWE and DTT possess significant sedative-hypnotic activity, which supports the popular use of Suanzaoren and Danshen for treatment of insomnia and provide the basis for new drug discovery. Furthermore, the results demonstrate that the combination of SWE and DTT may be preferable for the treatment of insomnia.

[Hyperspectral inversion models on verticillium wilt severity of cotton leaf]

The correlation of cotton leaf verticillium wilt severity level with raw hyperspectral reflectance, first derivative hyperspectral reflectance, and hyperspectral characteristic parameters was analyzed. Using linear and nonlinear regression methods, the hyperspectral remote sensing retrieval models of verticillium wilt severity level with remote sensing parameters as independent variables were constructed and validated. The result showed that spectral reflectance increased significantly in visible and short infrared wave band with the increase in the severity level, and this is especially significant in visible band. The raw spectral reflectance has the maximum coefficient of determination at 694 nm (R2 = 0.461 6) with severity level and the logarithm model constructed with reflectance at this point is the better one as compared to linear model. By the precision evaluation of retrieval models, the linear model with the first derivative reflectance at 717 nm as independent variable was proved to be the best, with R2 = 0.488 9, RMSE = 0.257 1, and relative error = 12.74%, for the estimation of verticllium wilt severity level of cotton leaf. The results provide a good basis for further studying monitoring mechanism of cotton verticillium wilt by remote sensing data, and have an important application in acquiring cotton disease information using hyperspectral remote sensing.

Intra- and inter-observer reproducibility of volume measurement of knee cartilage segmented from the OAI MR image set using a novel semi-automated segmentation method

OBJECTIVE

We developed a semi-automated method based on a graph-cuts algorithm for segmentation and volumetric measurements of the cartilage from high-resolution knee magnetic resonance (MR) images from the Osteoarthritis Initiative (OAI) database and assessed the intra- and inter-observer reproducibility of measurements obtained via this method.

DESIGN

MR image sets from 20 subjects of varying Kellgren-Lawrence (KL) grades (from 0 to IV) on fixed flexion knee radiographs were selected from the baseline double-echo and steady-state (DESS) knee MR images in the OAI database (0.B.1 Imaging Data set). Two trained radiologists independently performed the segmentation of knee cartilage twice using the semi-automated method. The volumes of segmented cartilage were computed and compared. The intra- and inter-observer reproducibility were determined by means of the coefficient of variation (CV%) of repeated cartilage segmented volume measurements. The subjects were also divided into the low- (0, I or II) and high-KL (III or IV) groups. The differences in cartilage volume measurements and CV% within and between the observers were tested with t tests.

RESULTS

The mean (+/-SD) intra-observer CV% for the 20 cases was 1.29 (+/-1.05)% for observer 1 and 1.67 (+/-1.14)% for observer 2, while the mean (+/-SD) inter-observer CV% was 1.31 (+/-1.26)% for session 1 and 1.79 (+/-1.72)% for session 2. There was no significant difference between the two intra-observer CV%'s (P=0.272) and between the two inter-observer CV%'s (P=0.353). The mean intra-observer CV% of the low-KL group was significantly smaller than that for the high-KL group for observer 1 (0.83 vs 1.86%: P=0.025). The segmentation processing times used by the two observers were significantly different (observer 1 vs 2): (mean 49+/-12 vs 33+/-6min) for session 1 and (49+/-8 vs 32+/-8min) for session 2.

CONCLUSION

The semi-automated graph-cuts method allowed us to segment and measure cartilage from high-resolution 3T MR images of the knee with high intra- and inter-observer reproducibility in subjects with varying severity of OA.

Pulmonary edema in the transurethral resection syndrome induced with mannitol 5%

Two patients developed the transurethral resection (TUR) syndrome after having absorbed mannitol 5% during TUR of the prostate. Both developed pulmonary edema and became severely hypoatremic (lowest serum sodium 99 and 97 mmol/l, respectively). Hypertonic saline was infused to raise the serum sodium level and plasma volume expansion used to combat hypotension. One patient also required positive-pressure ventilation and intravenous administration of norepinephrine. Both patients recovered completely.

TN curve: a novel 3D graphical representation of DNA sequence based on trinucleotides and its applications

In this paper, a novel 3D graphical representation of DNA sequence based on trinucleotides is proposed. This representation allows direct inspection of composition as well as distribution of trinucleotides in DNA sequence for the first time and avoids loss of information, from which one can obtain more information. Based on this novel model, six numerical descriptors of DNA sequence are deduced without complicated calculations, and the applications in similarities/dissimilarities analysis of coding sequences and conserved genes discrimination illustrate their utilities. In addition, two simple methods for similarities/dissimilarities analysis of coding sequences among different species are exploited by using two vectors composed of 64 and six components, respectively, which can provide convenient sequence alignment tools for both computational scientists and molecular biologists.

Clinical features of convulsive status epilepticus: a study of 220 cases in western China

BACKGROUND AND PURPOSE

Convulsive status epilepticus (CSE) is the most common and life-threatening form of status epilepticus (SE). The aim of this study was to describe the clinical features of CSE in western China.

METHODS

Convulsive status epilepticus patients hospitalized from January 1996 to October 2007 were prospectively observed. Logistic regression was used to identify predictors of prognosis.

RESULTS

The average age of CSE patients (n = 220) was 37.5 years (SD 20.31), 50% of the patients had a history of epilepsy. The primary cause of CSE was central nervous system infection (32.7%), followed by discontinuation or reduction of antiepileptic drugs (AEDs; 15.5%). The median duration of CSE was 5 h and median duration of seizures before treatment was 2 h; both were longer in rural patients than in urban patients (P < 0.05). The fatality rate on discharge was 15.9%. Logistic regression analysis showed the duration of CSE [odds ratio (OR) 1.05, 95% confidence interval (CI) 1.03-1.07], a history of epilepsy (OR 0.35, 95% CI 0.14-0.89), and respiratory depression (OR 5.96, 95% CI 2.49-14.24) were independent predictors of CSE prognosis.

DISCUSSION

Central nervous system infection and AEDs withdrawal in epilepsy patients were the most important causes of CSE. There is a large gap between antiepileptic therapy in China and European Status Epilepticus guidelines.

Bacterial endotoxin enhances colorectal cancer cell adhesion and invasion through TLR-4 and NF-kappaB-dependent activation of the urokinase plasminogen activator system

Perioperative exposure to lipopolysaccharide (LPS) is associated with accelerated metastatic colorectal tumour growth. LPS directly affects cells through Toll-like receptor 4 (TLR-4) and the transcription factor NF-κB. The urokinase plasminogen activator (u-PA) system is intimately implicated in tumour cell extracellular matrix (ECM) interactions fundamental to tumour progression. Thus we sought to determine if LPS directly induces accelerated tumour cell ECM adhesion and invasion through activation of the u-PA system and to elucidate the cellular pathways involved. Human colorectal tumour cell lines were stimulated with LPS. u-PA concentration, u-PA activity, active u-PA, surface urokinase plasminogen activator receptor (u-PAR) and TLR-4 expression were assessed by ELISA, colorimetric assay, western blot analysis and flow cytometry respectively. In vitro tumour cell vitronectin adhesion and ECM invasion were analysed by vitronectin adhesion assay and ECM invasion chambers. u-PA and u-PAR function was inhibited with anti u-PA antibodies or the selective u-PA inhibitors amiloride or WXC-340, TLR-4 by TLR-4-blocking antibodies and NF-κB by the selective NF-κB inhibitor SN-50. LPS upregulates u-PA and u-PAR in a dose-dependent manner, enhancing in vitro tumour cell vitronectin adhesion and ECM invasion by >40% (P<0.01). These effects were ameliorated by u-PA and u-PAR inhibition. LPS activates NF-κB through TLR-4. TLR-4 and NF-κB inhibition ameliorated LPS-enhanced u-PA and u-PAR expression, tumour cell vitronectin adhesion and ECM invasion. LPS promotes tumour cell ECM adhesion and invasion through activation of the u-PA system in a TLR-4- and NF-κB-dependent manner.

Analysis of differential gene expression in colorectal cancer and stroma using fluorescence-activated cell sorting purification

Tumour stroma gene expression in biopsy specimens may obscure the expression of tumour parenchyma, hampering the predictive power of microarrays. We aimed to assess the utility of fluorescence-activated cell sorting (FACS) for generating cell populations for gene expression analysis and to compare the gene expression of FACS-purified tumour parenchyma to that of whole tumour biopsies. Single cell suspensions were generated from colorectal tumour biopsies and tumour parenchyma was separated using FACS. Fluorescence-activated cell sorting allowed reliable estimation and purification of cell populations, generating parenchymal purity above 90%. RNA from FACS-purified and corresponding whole tumour biopsies was hybridised to Affymetrix oligonucleotide microarrays. Whole tumour and parenchymal samples demonstrated differential gene expression, with 289 genes significantly overexpressed in the whole tumour, many of which were consistent with stromal gene expression (e.g., COL6A3, COL1A2, POSTN, TIMP2). Genes characteristic of colorectal carcinoma were overexpressed in the FACS-purified cells (e.g., HOX2D and RHOB). We found FACS to be a robust method for generating samples for gene expression analysis, allowing simultaneous assessment of parenchymal and stromal compartments. Gross stromal contamination may affect the interpretation of cancer gene expression microarray experiments, with implications for hypotheses generation and the stability of expression signatures used for predicting clinical outcomes.

First Report of Ranunculus mild mosaic virus on Ranunculus asiaticus in Yunnan Province, China

In June 2007, a new viral disease occurred in commercial fields of Ranunculus asiaticus in the Yunnan Province of China. Infected plants exhibited mosaic symptoms and growth abnormalities. Viral disease incidence for this ornamental crop host in the Yunnan Province was estimated to range from 10 to 20%. Electron microscopic examination of negatively stained leaf-dip preparations from symptomatic plants identified long, flexuous linear particles (approximately 800 nm). The samples were tested using indirect antigen-coated plate (ACP)-ELISA. ACP-ELISA results showed that the leaf samples from symptomatic plants reacted positively to the potyvirus group antibody (Agdia Inc., Eklhart, IN). Total nucleic acid extracted from symptomatic plants was tested using reverse transcription (RT)-PCR with primers (S 5'-GGNAAAAYAGYGGNCARCC-3'; M4: 5'-GTTTTCCCAGTCACGAC-3' [N = A, G, C, or T; Y = C or T; and R = A or G]) designed to amplify the 3' terminal region of genomic RNA of the genus Potyvirus (1). RT-PCR produced a 1,650-bp amplification product that was cloned and sequenced (GenBank Accession No. EU684747). The sequenced portion showed 90 and 99% identity with the Ranunculus mild mosaic virus (RMMV) isolates (GenBank Accession Nos. DQ152191 and EF445546) from Italy and Israel, respectively (2). To our knowledge, this is the first report of RMMV in China. Infection from this virus may cause losses for cut-flower production of Ranunculus asiaticu and it is also a potential threat for international trade of Ranunculus germplasm. References: (1) J. Chen and J. P. Chen. Chin. J. Virol. 18:371, 2002. (2) M. Turina et al. Phytopathology 96:560, 2006.

Does isoflurane enhance rhinovirus replication and virus-induced cytokine secretion in airway epithelial cells?

BACKGROUND

There have been no previous studies regarding the effect of volatile anesthetics on human rhinovirus (RV) infection in airway epithelial cells of patients with an upper respiratory infection (URI). We have therefore evaluated in vitro the effect of isoflurane on RV infection in airway epithelial cells.

METHODS

A549 cells and RV-infected A549 cells were treated with isoflurane for 2 or 4 h. Surface expression of intercellular adhesion molecule-1 (ICAM-1) was assessed by flow cytometry, and effects on the secretion of interleukin (IL)-6 and IL-8 were measured by ELISA. The effect on RV replication in the cells was determined by viral titer.

RESULTS

Isoflurane treatment for 2 or 4 h had no significant effect on ICAM-1 expression and secretion of IL-6 and IL-8 in control cells. Isoflurane also had no significant additional effect on RV-induced ICAM-1 expression and secretion of IL-6 and IL-8. Viral titers were not significantly influenced by isoflurane.

CONCLUSION

Isoflurane treatment showed no additional effects with RV on ICAM-1 expression, secretion of IL-6 and IL-8, and viral titer in A549 cells. These results suggest that isoflurane itself may not increase further RV infections, inflammations, and viral replication in patients with a viral URI.

Online learning vector quantization: a harmonic competition approach based on conservation network

This paper presents a self-creating neural network in which a conservation principle is incorporated with the competitive learning algorithm to harmonize equi-probable and equi-distortion criteria. Each node is associated with a measure of vitality which is updated after each input presentation. The total amount of vitality in the network at any time is 1, hence the name conservation. Competitive learning based on a vitality conservation principle is near-optimum, in the sense that problem of trapping in a local minimum is alleviated by adding perturbations to the learning rate during node generation processes. Combined with a procedure that redistributes the learning rate variables after generation and removal of nodes, the competitive conservation strategy provides a novel approach to the problem of harmonizing equi-error and equi-probable criteria. The training process is smooth and incremental, it not only achieves the biologically plausible learning property, but also facilitates systematic derivations for training parameters. Comparison studies on learning vector quantization involving stationary and nonstationary, structured and nonstructured inputs demonstrate that the proposed network outperforms other competitive networks in terms of quantization error, learning speed, and codeword search efficiency.

Toward optimizing a self-creating neural network

This paper optimizes the performance of the growing cell structures (GCS) model in learning topology and vector quantization. Each node in GCS is attached with a resource counter. During the competitive learning process, the counter of the best-matching node is increased by a defined resource measure after each input presentation, and then all resource counters are decayed by a factor alpha. We show that the summation of all resource counters conserves. This conservation principle provides useful clues for exploring important characteristics of GCS, which in turn provide an insight into how the GCS can be optimized. In the context of information entropy, we show that performance of GCS in learning topology and vector quantization can be optimized by using alpha=0 incorporated with a threshold-free node-removal scheme, regardless of input data being stationary or nonstationary. The meaning of optimization is twofold: (1) for learning topology, the information entropy is maximized in terms of equiprobable criterion and (2) for leaning vector quantization, the use is minimized in terms of equi-error criterion.

[Real-time analysis of soil N and P with near infrared diffuse reflectance spectroscopy]

Improving the efficiency of fertilization is an effective method of enhancing income for farmers, but it depends on measuring the soil nutrients accurately and rapidly. Near infrared reflectance spectroscopy (NIRS) is a fast method to detect the soil nutrients. In order to evaluate the feasibility of using NIRS to determine the soil N and P contents, the soil samples were collected from different LULC (land use and land cover) types in Daxing district, Beijing, and their biochemical parameters were determined by traditional chemical method. Then, the near infrared reflectance spectra of the samples were acquired, and NIRS models were built using partial least square regression (PLS) and Fourier transform technology for the total N and total P. The determination coefficients of cross validation for the total N and total P were 0.862 6 and 0.668 5 respectively. Ten samples were used to test the performance of the models. The coefficients of correlation between the chemically determined value and the NIRS predicted one were 0.969 8(N) and 0.830 7(P) respectively. The root mean standard error of prediction for N and P were 0.009 5(%) and 0.008 6(%), respectively. The ratios of RMSEP to SD(RPD) were 3.78(N) and 1.69(P). The results showed that the NIRS could be used to evaluate the soil N accurately and the soil P roughly.

Statins attenuate polymethylmethacrylate-mediated monocyte activation

BACKGROUND

Periprosthetic osteolysis precipitates aseptic loosening of components, increases the risk of periprosthetic fracture and, through massive bone loss, complicates revision surgery and ultimately is the primary cause for failure of joint arthroplasty. The anti-inflammatory properties of HMG-CoA reductase inhibitors belonging to the statin family are well recognized. We investigated a possible role for status in initiating the first stage of the osteolytic cycle, namely monocytic activation.

METHODS

We used an in vitro model of the human monocyte/macrophage inflammatory response to poly-methylmethacrylate (PMMA) particles after pretreat-ing cells with cerivastatin, a potent member of the statin family. Cell activation based upon production of TNF-alpha and MCP-1 cytokines was analyzed and the intracellular Raf-MEK-ERK signal transduction pathway was evaluated using western blot analysis, to identify its role in cell activation and in any cerivastatin effects observed.

RESULTS

We found that pretreatment with cerivastatin significantly abrogates the production of inflammatory cytokines TNF-alpha and MCP-1 by human monocytes in response to polymethylmethacrylate particle activation. This inflammatory activation and attenuation appear to be mediated through the intracellular Raf-MEK-ERK pathway.

INTERPRETATION

We propose that by intervening at the upstream activation stage, subsequent osteoclast activation and osteolysis can be suppressed. We believe that the anti-inflammatory properties of statins may potentially play a prophylactic role in the setting of aseptic loosening, and in so doing increase implant longevity.

Detection of human parvovirus B19 in papillary thyroid carcinoma

To evaluate whether parvovirus B19, a common human pathogen, was also involved in papillary thyroid carcinoma (PTC), 112 paraffin-embedded thyroid specimens of benign nodules, papillary, medullary and follicular carcinomas, and normal controls were examined for B19 DNA and capsid protein by nested PCR, in situ hybridisation (ISH) and immunohistochemistry (IHC). The expression of the nuclear factor-κB (NF-κB) was investigated by IHC. The results showed B19 DNA commonly exists in human thyroid tissues; however, there were significant differences between PTC group and normal controls, and between PTC and nonneoplastic adjacent tissues (P<0.001). The presence of viral DNA in PTC neoplastic epithelium was confirmed by laser-capture microdissection and sequencing of nested PCR products. B19 capsid protein in PTC group was significantly higher than that of all the control groups and nonneoplastic adjacent tissues (P⩽0.001). Compared with control groups, the activation of NF-κB in PTC group was significantly increased (P⩽0.02), except for medullary carcinomas, and the activation of NF-κB was correlated with the viral protein presence (P=0.002). Moreover, NF-κB was colocalised with B19 DNA in the neoplastic epithelium of PTC by double staining of IHC and ISH. These results indicate for the first time a possible role of B19 in pathogenesis of PTC.