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Little is known about the responses of soil fungal communities to revegetation of mine wastelands, representing a major gap in the knowledge needed to improve the performances of revegetation schemes for mine wastelands. To shed some light on this matter, we reestablished 4000 m2of vegetation on an extremely acidic (pH 2.5) copper mine tailings pond and collected soil samples from three different types of habitats: amended layer of the reclaimed tailings (ALRT), unamended layer of the reclaimed tailings (ULRT), and unreclaimed tailings (UT). Soil fungal communities in the 120 samples collected in two consecutive years were characterized via high-throughput sequencing. The fungal diversities at ALRTand ULRT were found to be significantly higher than those at UT. Ascomycota whose relative abundance ranged from 74.5% to 98.4% was the most predominant phylum across all habitats, exhibiting the lowest predominance at ALRT. Two acidophilic fungal genera, Acidomycesand Acidiella, dominated UT with relative abundances being as high as 37.8% and 15.2%, respectively. In contrast, three genera with plant growth-promoting species (Talaromyces, Trichodermaand Penicillium) were abundant at ULRT and ALRT. Remarkably, their relative abundances at ULRT could be up to 29.0%, 26.9% and 9.7%, respectively. The three types of habitats differed considerably in the overall soil fungal community composition at species level, which became more pronounced as time progressed. The abovementioned differences between habitats in soil fungal community features were related to the reduced availability of soil copper and zinc. These results improved our understanding of fungal ecology of mine wastelands.

In this paper, we systematically designed vdW heterostructures by stacking the GaN and Janus-WSSe monolayer and chose the structure that has potential to be used as photocatalysts of water splitting for further investigation. By applying a biaxial strain, the electronic, optical and photocatalytic properties of this heterostructure were investigated to explore whether it is suitable for photocatalyst of water splitting. Results show the heterostructure show a type II band alignment under a − 2% strain, and the band gap is 2.26 eV which is fit to absorb solar light. The band edge of it straddles the water redox potentials at pH = 7. And the absorption coefficient in the visible and UV light region is large, especially for ultraviolet light. In a word, this GaN/Janus-WSSe vdW heterostructure under a − 2% biaxial external strain is a potential solar photocatalyst for water splitting at pH = 7.

Mining is among the human activities with widest environmental impacts, and mining-impacted environments are characterized by high levels of metals that can co-select for antibiotic resistance genes (ARGs) in microorganisms. However, ARGs in mining-impacted environments are still poorly understood. Here, we conducted a comprehensive study of ARGs in such environments worldwide, taking advantage of 272 metagenomes generated from a global-scale data collection and two national sampling efforts in China. The average total abundance of the ARGs in globally distributed studied mine sites was 1572 times per gigabase, being rivaling that of urban sewage but much higher than that of freshwater sediments. Multidrug resistance genes accounted for 40% of the total ARG abundance, tended to co-occur with multimetal resistance genes, and were highly mobile (e.g. on average 16% occurring on plasmids). Among the 1848 high-quality metagenome-assembled genomes (MAGs), 85% carried at least one multidrug resistance gene plus one multimetal resistance gene. These high-quality ARG-carrying MAGs considerably expanded the phylogenetic diversity of ARG hosts, providing the first representatives of ARG-carrying MAGs for the Archaea domain and three bacterial phyla. Moreover, 54 high-quality ARG-carrying MAGs were identified as potential pathogens. Our findings suggest that mining-impacted environments worldwide are underexplored hotspots of multidrug resistance genes.

Cretaceous is the key exploration target layer in the eastern depression of North Yellow Sea basin, which has a good prospect for oil and gas exploration. Its huge oil and gas resource potential has attracted great attention from petroleum geologists. In this study, the main rock types, reservoir space types, petrophysical characteristics and main controlling factors of Cretaceous reservoir are studied through core observation, thin section identification, petrophysical analysis and scanning electron microscope observation. The results indicate that the main rock types of Cretaceous reservoir in the eastern depression of North Yellow Sea basin are lithic arkose, feldspar lithic sandstone, some feldspar sandstone and a small amount of lithic sandstone. The average porosity is 6.9%, and the average permeability is 0.46 × 10−3μm, so Cretaceous reservoir in the study area has poor petrophysical characteristics and belongs to low porosity and low permeability reservoir. Cretaceous reservoirs in the study area mainly develop in secondary pores, which are dominated by dissolution pores (including intragranular pores, intercrystalline pores and cleavage pores), followed by fractures. The main factors affecting petrophysical characteristics of Cretaceous reservoir in the study area are provenance properties, sedimentation, diagenesis (including compaction, cementation and dissolution) and tectonism. The provenance properties and sedimentation are the prerequisite conditions affecting petrophysical characteristics. Petrophysical characteristics of feldspar sandstone of Cretaceous reservoir in the study area and lithic arkose are better than that of feldspar lithic sandstone. Both compaction and cementation reduce the porosity and permeability of Cretaceous reservoir in the study area and make petrophysical characteristics become poor, whereas the dissolution and tectonism play an important role in improving petrophysical characteristics of Cretaceous reservoir.

Cyclopropane is a prevalent structural unit in natural products and bioactive compounds. While the transition metal-catalyzed alkene cyclopropanation of functionalized compounds such as α-diazocarbonyl derivatives has been well established and provides straightforward access to cyclopropanes, cyclopropanation directly from the more stable and simpler methylene compounds has remained an unsolved challenge despite the highly desirable benefits of minimal prefunctionalization and increased operational safety. Herein we report an electrocatalytic strategy for the cyclopropanation of active methylene compounds, employing an organic catalyst. The method shows a broad substrate scope and excellent scalability, requires no metal catalyst or external chemical oxidant, and provides convenient access to several types of cyclopropane-fused heterocyclic and carbocyclic compounds. Mechanistic investigations suggest that the reactions proceed through a radical–polar crossover process to form the two new carbon–carbon bonds in the nascent cyclopropane ring.

Mining is among the human activities with widest environmental impacts, and mining-impacted environments are characterized by high levels of metals that can co-select for antibiotic resistance genes (ARGs) in microorganisms. However, ARGs in mining-impacted environments are still poorly understood. Here, we conducted a comprehensive study of ARGs in such environments worldwide, taking advantage of 272 metagenomes generated from a global-scale data collection and two national sampling efforts in China. The average total abundance of the ARGs in globally distributed studied mine sites was 1572 times per gigabase, being rivaling that of urban sewage but much higher than that of freshwater sediments. Multidrug resistance genes accounted for 40% of the total ARG abundance, tended to co-occur with multimetal resistance genes, and were highly mobile (e.g. on average 16% occurring on plasmids). Among the 1848 high-quality metagenome-assembled genomes (MAGs), 85% carried at least one multidrug resistance gene plus one multimetal resistance gene. These high-quality ARG-carrying MAGs considerably expanded the phylogenetic diversity of ARG hosts, providing the first representatives of ARG-carrying MAGs for the Archaea domain and three bacterial phyla. Moreover, 54 high-quality ARG-carrying MAGs were identified as potential pathogens. Our findings suggest that mining-impacted environments worldwide are underexplored hotspots of multidrug resistance genes.

Little is known about the changes in soil microbial phosphorus (P) cycling potential during terrestrial ecosystem management and restoration, although much research aims to enhance soil P cycling. Here, we used metagenomic sequencing to analyse 18 soil microbial communities at a P-deficient degraded mine site in southern China where ecological restoration was implemented using two soil ameliorants and eight plant species. Our results show that the relative abundances of key genes governing soil microbial P-cycling potential were higher at the restored site than at the unrestored site, indicating enhancement of soil P cycling following restoration. The gcdgene, encoding an enzyme that mediates inorganic P solubilization, was predominant across soil samples and was a major determinant of bioavailable soil P. We reconstructed 39 near-complete bacterial genomes harboring gcd, which represented diverse novel phosphate-solubilizing microbial taxa. Strong correlations were found between the relative abundance of these genomes and bioavailable soil P, suggesting their contributions to the enhancement of soil P cycling. Moreover, 84 mobile genetic elements were detected in the scaffolds containing gcdin the 39 genomes, providing evidence for the role of phage-related horizontal gene transfer in assisting soil microbes to acquire new metabolic potential related to P cycling.

Little is known about the changes in soil microbial phosphorus (P) cycling potential during terrestrial ecosystem management and restoration, although much research aims to enhance soil P cycling. Here, we used metagenomic sequencing to analyse 18 soil microbial communities at a P-deficient degraded mine site in southern China where ecological restoration was implemented using two soil ameliorants and eight plant species. Our results show that the relative abundances of key genes governing soil microbial P-cycling potential were higher at the restored site than at the unrestored site, indicating enhancement of soil P cycling following restoration. The gcdgene, encoding an enzyme that mediates inorganic P solubilization, was predominant across soil samples and was a major determinant of bioavailable soil P. We reconstructed 39 near-complete bacterial genomes harboring gcd, which represented diverse novel phosphate-solubilizing microbial taxa. Strong correlations were found between the relative abundance of these genomes and bioavailable soil P, suggesting their contributions to the enhancement of soil P cycling. Moreover, 84 mobile genetic elements were detected in the scaffolds containing gcdin the 39 genomes, providing evidence for the role of phage-related horizontal gene transfer in assisting soil microbes to acquire new metabolic potential related to P cycling.

Plastic marine debris is known to harbor a unique microbiome (termed the “plastisphere”) that can be important in marine biogeochemical cycles. However, the temporal dynamics in the plastisphere and their implications for marine biogeochemistry remain poorly understood. Here, we characterized the temporal dynamics of nitrifying communities in the plastisphere of plastic ropes exposed to a mangrove intertidal zone. The 39-month colonization experiment revealed that the relative abundances of Nitrospiraand CandidatusNitrosocosmicus representatives increased over time according to 16S rRNA gene amplicon sequencing analysis. The relative abundances of amoAgenes in metagenomes implied that comammox Nitrospirawere the dominant ammonia oxidizers in the plastisphere, and their dominance increased over time. The relative abundances of two metagenome-assembled genomes of comammox Nitrospiraalso increased with time and positively correlated with extracellular polymeric substances content of the plastisphere but negatively correlated with NH4+concentration in seawater, indicating the long-term succession of these two parameters significantly influenced the ammonia-oxidizing community in the coastal plastisphere. At the end of the colonization experiment, the plastisphere exhibited high nitrification activity, leading to the release of N2O (2.52 ng N2O N g−1) in a 3-day nitrification experiment. The predicted relative contribution of comammox Nitrospirato N2O production (17.9%) was higher than that of ammonia-oxidizing bacteria (4.8%) but lower than that of ammonia-oxidizing archaea (21.4%). These results provide evidence that from a long-term perspective, some coastal plastispheres will become dominated by comammox Nitrospiraand thereby act as hotspots of ammonia oxidation and N2O production.Graphical Abstract

In the field of catalytic asymmetric synthesis, the less-treated path lies in oxidative catalytic asymmetric transformations. The hurdles of pinpointing the appropriate chemical oxidants and addressing their compatibility issues with catalysts and functionalities present significant challenges. Organic electrochemistry, employing traceless electrons for redox reactions, is underscored as a promising solution. However, the commonly used electrolysis in batch cells introduces its own set of challenges, hindering the advancement of electrochemical asymmetric catalysis. Here we introduce a microfluidic electrochemistry platform with single-pass continuous flow reactors that exhibits a wide-ranging applicability to various oxidative asymmetric catalytic transformations. This is exemplified through the sulfenylation of 1,3-dicarbonyls, dehydrogenative C–C coupling, and dehydrogenative alkene annulation processes. The unique properties of microfluidic electrochemical reactors not only eliminate the need for chemical oxidants but also enhance reaction efficiency and reduce the use of additives and electrolytes. These salient features of microfluidic electrochemistry expedite the discovery and development of oxidative asymmetric transformations. In addition, the continuous production facilitated by parallel single-pass reactors ensures straightforward reaction upscaling, removing the necessity for reoptimization across various scales, as evidenced by direct translation from milligram screening to hectogram asymmetric synthesis.

Lower back pain (LBP) is the most common disease in orthopedic clinics world-wide. A classic Fangji of traditional Chinese medicine, Duhuo Jisheng Decoction (DHJSD), has been proven clinically effective for LBP but its therapeutic mechanisms remain unclear. We hypothesized that DHJSD might relieve LBP through inhibiting the exaggerated proinflammatory cytokines and extracellular matrix (ECM) degradation. Thus, we studied the effects of DHJSD on stromal cell-derived factor-1 (SDF-1)-induced inflammation and ECM degradation in human nucleus pulposus cells (hNPCs). The primary hNPCs were isolated from either degenerated human intervertebral disc (HID) of LBP patients or normal HID of lumbar vertebral fracture patients, and cultured in vitro. The cells were treated with SDF-1 (10 ng/mL) and subsequently with different concentrations (100–500 μg/mL) of DHJSD for 24 h, respectively. We found that application of DHJSD significantly antagonized the SDF-1-induced production of proinflammatory cytokines and reduction of aggrecan and type II collagen in the hNPCs. DHJSD also markedly reduced the SDF-1-induced increase of CXCR4 and p-p65 and inhibited the nuclear translocation of p65 in the hNPCs. DHJSD, CXCR4-siRNA, and NF-κB inhibitor (BAY11-7082) caused the same inhibition of exaggerated proinflammatory cytokines in the SDF-1-treated hNPCs. These results provided compelling evidence that DHJSD may inhibit the generation of proinflammatory mediators and ECM degradation of HID through an orchestrated targeting at multiple molecules in the SDF-1/CXCR4/NF-κB pathway, thus offered novel mechanistic insights into the clinical effectiveness of DHJSD on LBP.

The difficulty of releasing nutrients from soils in karst areas limits the yield of local crops and leads to poverty. In this study, two strains of plant growth-promoting rhizobacteria (PGPR) were isolated from the rhizosphere soil of typical plants in karst areas, which were both identified as Bacillussp. and named GS1 and N1. And two isolates were used to construct a composite PGPR named MC1. These three strains of PGPR were used for soil inoculation in the pot experiment and field trial and their capacity to promote rice development was assessed. The results showed that MC1 inoculation exhibited notable rice growth-promoting ability in pot experiments, and, respectively, had an increment of 16.96, 18.74, and 11.50% in shoot biomass, total biomass, and rice height compared with control. This is largely attributed to PGPR’s capacity to secrete phytohormones and soil enzymes, particularly urease (UE) in GS1, whose secreted UE content was significantly higher by 12.18% compared to the control. When applied to the field, MC1 inoculation not only increased rice yield by 8.52% and the available nutrient content in rice rhizosphere soil, such as available phosphorus (AP) and exchangeable magnesium (EMg); but also improved the abundance of beneficial rhizobacteria and the diversity of microbial communities in rice rhizosphere soil. Results in this study revealed that inoculated PGPR played a major role in promoting rice growth and development, and a new strategy for facilitating the growth of rice crops in agriculture was elucidated.

The annular discharge orifice is a key parameter for the design of a shock transmission unit (STU). The proper dimension of the annular discharge orifice can make the stiffness difference of STU maximum in different conditions. Making use of three laws of fluid mechanics, the mathematical model for designing annular discharge orifice was developed. The STUs were subjected to the slow movement test, the fast movement test and the simulated dynamic test. During the slow movement test, the resistance force does not exceed 10% of the nominal rated force; during the simulated dynamic test, the deflection between the point of zero load and the point of maximum load does not exceed 12 mm, and the deflection during the sustained load portion of the test does not exceed 12 mm; during the fast movement test, the force can maintain the nominal rated force. The validity of the mathematical model is verified by these testing, and the mathematical model can instruct the design of annular discharge orifice of STU.

With the development of game industry, the requirements of game AI are also increasing. Recently a planning formalism called HTN (Hierarchical Task Network) was used to design AI behaviors. In this paper we describe how to implement an anytime planner based on HTN to handle a dynamic environment, which is the key feature of computer game worlds. This planner allows agent to interrupt its sequence of actions at anytime based on the changes of environment meanwhile return a valid replacement plan. We use Unreal Tournament 2004 which is a famous first-person shooter game as the platform and test our anytime planner.

In this paper, a review of developments in the dynamic characteristics of traditional and inflatable solar array is presented. Three major aspects that affect the dynamic behavior of solar array are reviewed: component flexibility, joint clearance and thermally induced vibration. Important results and methods of exploring the dynamic characteristics of inflatable solar array are discussed. Future research areas in dynamic characteristics of solar array are identified as damping mechanism of inflatable structure, the relationship between pressurization level and damping ratio, application of more advanced contact model, dynamic characteristics of solar array made of new materials and consideration of deformation in multiple dimensions.

Space manipulator is an important tool for spacecraft to complete a variety of tasks in space. The trajectory precision of the manipulator determines whether the mechanism performs normally. Nowadays the harmonic drive is widely used as the reducer in the space manipulator, which may influence the dynamical properties of the flexible space manipulator. This paper establishes the dynamical models of space manipulator considering the harmonic hysteresis phenomenon derived from the harmonic reducer. A numerical simulation is proposed to analyze the nonlinear dynamic characteristics of flexible space manipulator with harmonic drive. The results of angular velocities reveal that non-linear and high-frequency disturbance detected in the output dynamical property is caused by flexibility of the space manipulator. Moreover, the observed hysteresis phenomenon in the dynamic behavior is not only determined by the flexibility of manipulator but the transmission feature embedded the harmonic drive.

Less of edge and texture information existed in traditional visual attention model in target detection due to extract only the color, brightness, directional characteristics, as well as direct sum fusion rule ignoring the difference in each characteristic. A improved model is proposed by introduced the edge, texture and the weights in fusion rules in visual computing model. First of all, DOG is employed in extracting the edge information on the basis of obtained brightness feature with multi-scale pyramid using the ITTI visual computing model; the second, the non-linear classification is processing in the six parameters of the mean and standard deviation of the gray contrast, relativity and entropy based on the GLCM; finally, the fusion rule of global enhancement is employed for combination of multi-feature saliency maps. The comparison experimental results on variegated natural scene display, relative to the ITTI calculation model, there is more effective with the application of the model in this paper, the interested area and the order to shift the focus are more in line with the human visual perception, the ability of target detection is strengthening in variegated natural scene. Further shows that the proposed edge and texture features introduced in the primary visual features to be effective, the introduction of each feature significant weighting factor is reasonable in the feature map integration phase.

The multi-sensor image fusion is the effective practices to increase the image information, highlight the detection superiority, reduce fuzzy understanding and to reduce data redundancy. Image fusion based on wavelet transform, the image wavelet decomposition processing only exists in the low-frequency, when the image contains high-frequency information, such as a large number of small edge or texture, which can not extract the feature information of the image, so resulting in the fusion is ineffective. In response to these problems, the use of image fusion algorithm based on wavelet packet transform, continue to break down, while the low-frequency further decomposition of the high-frequency of the image, extracts image feature information more effectively. In the same conditions of wavelet function, decomposition level, the fusion policy, comparative analysis has been researched on wavelet transform and wavelet packet transform on the same parameters of the information entropy, average gradient, standard deviation, spatial frequency, the results show that, image fusion of the algorithm based on wavelet packet transform are the highest and the better. In the other hand, in order to investigate the fusion effectiveness of the decomposition level on the same wavelet function conditions, fusion image parameters, such as entropy, average gradient, standard deviation, and spatial frequency, have been calculated using the db3 wavelet function corresponding to the decomposition level 1-5. The results show that the fusion effectiveness should achieve the best with wavelet decomposition level of 3 or 2.

The article introduces the vibrating test of gear box in the engineroom of 1.25MW wind turbine in wind farm in Inner Mongolia province, and obtains the detailed structure form and parameters of the wind turbine, and has real-time monitoring on four wind turbines of four typical areas in the wind farm, and gets time domain response of wind turbine. The on-line condition monitoring was applied on full power test platform that uses 1.25MW wind turbine, vibrating test was used for key parts in the engineroom of wind turbine, spindle, gearbox, generator ,generator underframe and so on, and the natural frequency of generator underframe and time and frequency domain response of gearbox, ring gear, generator and generator underframe are obtained. Through two tests, the vibration characteristic in the engineroom is obtained.

Poly vinyl pyrrolidone (PVP(K30)) / Bisphenol A Dicyanate ester (BADCy) blends were fabricated to increase the toughness of BADCy by blending processing in this paper. Curing parameters were determined by gelation time curves and differential scanning calorimetry (DSC) of the systems. Fourier transform infrared spectrometry (FTIR) and DSC data were employed to show the curing behavior and kinetics of the systems. Mechanical properties of the cured resin had been improved rapidly with the increasing of PVP(K30) at low mass fraction, but would decrease when mass fractions of PVP(K30) were higher than 15%. Scanning electron micrograph (SEM) was applied to show the microstructures of the cured matrixes. Based on the thermogravimetric analysis (TGA) curves, water absorption curves, SEM images and dielectric properties of the blends, it can be concluded that the addition of PVP(K30) can improve the toughness of BADCy greatly with little loss of other properties.

Zein is a biocompatible and biodegradable corn protein with promising properties for biomedical applications. It is hydrophobic with the ability to self-assemble in an aqueous medium. It can also form a gel in hydroalcoholic solvents at higher concentrations. Few studies have investigated the biomedical significance of zein gels. Herein, we exploited the injectability and water-responsive increase in stiffness of zein gel to achieve hemostasis by physical blockage of the wound and clot formation. The release of components from the gel further aided blood clotting and gave a higher clot strength than a natural clot, which can prevent rebleeding. Rabbit aortic injury and swine femoral artery injury models were used to evaluate the hemostatic efficacy of the zein gel. Zein gel was effective in both hemostatic models without applying external compression due to an in situincrease in stiffness, while the control (Celox™ Gauze) required external compression at the wound site. The zein gel was easily removed after hemostasis due to hydrophobic self-assembly. Overall, zein gel is proposed as an effective hemostatic product for any wound shape owing to its good shape adaptability and rapid in situblood-responsive stiffness increase.

The chitosan scaffold we prepared have a high porosity of about 90% with pore sizes from 50 to 200[removed info]m. Lactose was conjugated onto the inner surface of the highly porous chitosan scaffold. It was used as substrate for rat hepatocytes culture. The cell attachment ratio was much higher than on monolayer membrane and non-modified porous scaffold. Metabolic activities of the cells were evaluated in terms of albumin secretion and urea synthesis. It was found that hepatocytes cultured on the modified scaffolds showed an increase in albumin secretion during the first 4 days and were more stable than that on non-modified scaffold. The results showed that the microstructure of porous scaffolds provides large surface for cells to adhere and facilitates nutrient and oxygen transportation. Such lactose modified scaffold has a potential application in bioartificial liver support system.

The water‐based polyacrylate microemulsion for ultrahigh molecular weight polyethylene (UHMWPE) fibers adhesive coating was synthesized by the emulsion polymerization of methyl methacrylate (MMA), butyl acrylate (BA), acrylic acid (AA), and hydroxyethyl acrylate (HEA) in the presence of a composite of sodium lauryl sulfate (SLS), OP‐10, and n‐octyl alcohol (NOA) as the emulsifier. The effects of the mass fraction of emulsifier and the reaction time on the properties of emulsion and its membrane were investigated. When m(BA) : m(MMA) : m(AA) : m(HEA) was 50 : 50 : 3 : 10 (wt ratio) and the mass fraction of emulsifier was 13 wt % and the reaction time was 3 h at 80°C, the latex particle diameter was 30 nm tested by transmission electron microscope (TEM). The Fourier transform infrared (FTIR) spectrometer and differential scanning calorimeter (DSC) were used to characterize the chemical structure and the glass transition temperature (Tg) of microemulsion membrane. The application results showed that this microemulsion was an ideal adhesive coating for UHMWPE fibers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006

Cisplatin resistant (CP-r) cells often show decreased uptake of cisplatin in association with reduced cell surface proteins and decreased endocytosis. In this report, two major [(14)C]carboplatin-binding proteins were identified as filamin and actin by photoaffinity labeling and mass spectrometry. Decreased expression of these two proteins was found in two different human CP-r cell lines (KB-CP20 and 7404-CP20), in comparison with their parental cell lines (KB-3-1 and BEL-7404), respectively. Disorganization of beta-actin and filamin 250 and 90 was also detected in these CP-r cells by confocal microscopy. Transfection of a wild-type actin-enhanced green fluorescent protein (EGFP) expression vector into 7404-CP20 cells resulted in a nonfilamentous actin-EGFP distribution compared with a normal distribution in the cisplatin-sensitive BEL-7404 cells, suggesting that cytoskeletal organization is disturbed in the CP-r cells. The identification of actin and filamin as [(14)C]carboplatin-binding proteins and decreased expression and disorganization of several cytoskeletal proteins in CP-r cells provide a molecular and cellular basis for the known defect in endocytosis in these cells.

Resistance to cisplatin, one of the most widely used anticancer chemotherapeutic agents, is a major clinical problem. There is no effective way to predict development of cisplatin resistance in cancers. As determined by reverse transcription-polymerase chain reaction and Western blotting, the expression of gamma-catenin, an adherens junction protein, was decreased in KB-CP20 and 7404-CP20 cells compared with parental-sensitive cells. Short-term treatment with cisplatin of the parental cells resulted in proteolysis of gamma-catenin as evaluated in membrane pellet preparations, and the extent of cleavage increased as cisplatin concentration was raised from 1 to 5 microg/ml during 1 h of treatment. Uncleaved cytoplasmic gamma-catenin increased under the same conditions. These biochemical results were supported by confocal microscopy, which showed a loss of gamma-catenin from adherens plaques after cisplatin treatment. Cleavage of gamma-catenin was specific to cisplatin treatment in that cleavage did not occur after treatment with doxorubicin and cytosine arabinoside. Pretreatment of KB and 7404 cells with cisplatin for 1 h resulted in reduced uptake of [(14)C]carboplatin, suggesting that the biochemical changes induced by cisplatin treatment, including cleavage of gamma-catenin, could affect the ability of cells to internalize platinum compounds. Cells transfected with the gamma-catenin gene are sensitive to cisplatin compared with cells transfected with a control vector. Our data suggest that proteolysis and altered localization of gamma-catenin are early markers for the response of cells to cisplatin, and reduced levels of gamma-catenin in resistant cells may indicate an important role for gamma-catenin in mediating or modulating the toxicity of cisplatin in cancer cells.

Objective: To observe the relationship of deep-slow respiratory pattern and respiratory impedance(RI) in patients with chronic obstructive pulmonary disease (COPD).Methods: RI under normal respiration and during deep-slow respiration was measured one after the other with impulse oscillometry for 8 patients with COPD and for 9 healthy volunteers as control.Results: When respiration was changed from normal pattern to the deep-slow pattern, the tidal volume increased and respiratory frequency significantly decreased in both groups (P< 0. 01), the total respiratory impedance (Z respir) showed a decreasing trend in COPD group, but with no obvious change in the control group. No change in the resonant frequency (fres) was found in both groups, and the respiratory viscous resistance obviously decreased in the COPD group(R5: P=0.0168; R20: P=0.0498; R5-R20: P=0.0388), though in the control group it was unchanged.Conclusion: IOS detection could reflect the response heterogeneity of different compartments of respiratory system during tidal breathing. During deep-slow respiration, the viscous resistance in both central airway and peripheral airway was decreased in patients with COPD. RI measurement by impulse oscillometry may be a convenient pathophysiological method for studying the application of breathing exercise in patients with COPD.