The chlorophyll fluorescence parameters of Kobresia humilis Serg. and Polygonum viviparum L. grown at two different altitudes (3?200 m, 3?980 m) were measured and the ultrastructure of chloroplasts were observ...The chlorophyll fluorescence parameters of Kobresia humilis Serg. and Polygonum viviparum L. grown at two different altitudes (3?200 m, 3?980 m) were measured and the ultrastructure of chloroplasts were observed for studying the photosynthetic adaptability of plants to the influences of stress conditions in alpine environment. Rfd _values, the vitality index, in leaves of K. humilis and P.viviparum grown at 3?980 m were higher than those at 3?200 m. The higher ratio of F v/F o and F v/F m in leaves of K. humilis and P.viviparum indicated that the rate of photosynthetic conversion of light energy increased at higher altitude. Ratios of F v/F o and F v/F m and Rfd _values in K.humilis were higher than that in P.viviparum grown at the same altitude. There were more irregular chloroplasts in leaves of both species grown at higher altitude. Many irregular chloroplasts such as swollen thylakoid, deformed chloroplast envelope, were observed in P.viviparum grown at 3?980 m, but few in K. humilis . These results were discussed in relation to the photosynthetic adaptability of alpine plants and the different adaptive competence between K.humilis and P.viviparum .展开更多
Wheat ( Triticum aestivum L.) plants were grown under ambient and doubled_CO 2(plus 350 μL/L) concentration in cylindrical open_top chamber to examine their effects on the ultrastructure, supramolecular architect...Wheat ( Triticum aestivum L.) plants were grown under ambient and doubled_CO 2(plus 350 μL/L) concentration in cylindrical open_top chamber to examine their effects on the ultrastructure, supramolecular architecture, absorption spectrum and low temperature (77 K) fluorescence emission spectrum of the chloroplasts from wheat leaves. The results were briefly summarized as follows: (1) The wheat leaves possessed normally developed chloroplasts with intact grana and stroma thylakoid membranes; The grana intertwined with stroma thylakoid membranes and increased slightly in stacking degree and the width of granum, in spite of more accumulated starch grains within the chloroplasts than those in control; (2) The particle density in the stacked region of the endoplasmic fracture face (EFs) and protoplasmic fracture face (PFs) and in the unstacked region the endoplasmic fracture face (EFu) and the protoplasmic fracture face (PFu) was significantly higher than that of control. Furthermore, in some cases many more particles on EFs faces of thylakoid membranes appeared as a paracrystalline particle array; (3) The variations in the structure of chloroplasts were consistent with the absorption spectra and the low temperature (77 K) fluorescence emission spectra of the chloroplasts developed under the doubled_CO 2 concentration. Results indicate that the capability of light energy absorption of chloroplasts and regulative capability of excitation energy distribution between PSⅡ and PSⅠ were raised by doubled_CO 2 concentration. This is very favorable for final productivity of wheat.展开更多
The ultrastructural distribution and active location of ATPase and the ultrastructural variations were investigated in mesophyll cells of Cyclocarya paliurus seedlings after iso-osmotic salt/water treatments in combin...The ultrastructural distribution and active location of ATPase and the ultrastructural variations were investigated in mesophyll cells of Cyclocarya paliurus seedlings after iso-osmotic salt/water treatments in combination with calcium regulation. C. paliurus seed- lings were treated with five groups (control, 85 mM NaCl, 85 mM NaCl+ 12 mM Ca(NO3)2, PEG iso-osmotic to 85 mM NaCl and PEG iso-osmotic to 85 mM NaCl+12 mM Ca(NO))2) in a hydroponic system in a phytotron. Results show that under normal growth conditions the ATPase activity was low and the enzyme was primarily located on the nucleus. After 12 days of iso-osmotic salt/water treatments, ATPase activity on the tonoptast increased. Osmiophilic globules for iso-osmotic water treatment were greater than that for iso-osmotie salt treatments. The ATPase activity increased and was mostly transferred onto the nucleus for calcium regulation treatment under iso- osmotic salt/water stresses, and the osmiophilic globules significantly decreased under iso-osmotic water stress with calcium regulation. The ATPase located on the nucleus indicated that the degree of salt/drought damage that seedlings suffered was slighter, while the amount of the enzyme located on the tonoplast showed that the degree of salt/drought damage there was more serious. After 4 and 20 days of iso- osmotic treatments, the injury suffered by the leaf ultrastructures of C. paliurus seedlings for iso-osmotic treatment with calcium regula- tion was lower than those without calcium regulation, especially for the iso-osmotic water treatments. Preliminary analysis suggests that the iniury suffered by C. paliurus seedlings was lower for iso-osmotic salt treatments than for iso-osmotic water treatments, while the effect of calcium regulation under iso-osmotic water stress was greater than that of the iso-osmotic salt stress.展开更多
With the development of the multicellular nodules in the leaves of Hypericum per plastids increased both in number and volume, and some plastids degenerated and were surrounded by dark tubular elements and vesicles. S...With the development of the multicellular nodules in the leaves of Hypericum per plastids increased both in number and volume, and some plastids degenerated and were surrounded by dark tubular elements and vesicles. Some vesicles fused with vacuoles and secreted substances into vacuoles. There are many multivesicles, multimembrane structures and osmiophilic droplets in vacuoles of nodule cells. Meanwhile, dictyosome secreted vesicles into the vacuoles. However, there is a large central vacuole completely filled with secretory materials (hypericin) in matured multicellular nodules. This suggests that the osmiophilic droplets may be a precursor of hypericin originated from the degenerated plastids. There were abundant endoplasmic reticulums and dictyosomes between the plastids and osmiophilic droplets, suggesting that they may be involved in the synthesis and/or transport of the precursor of hypericin.展开更多
The authors have studied the spectroscopic characteristics and the fluorescence lifetime for the chloroplasts from spinach (Spinacia oleracea L.) and water hyacinth (Eichhornia crassipes (Mart) Solms.) plant leaves by...The authors have studied the spectroscopic characteristics and the fluorescence lifetime for the chloroplasts from spinach (Spinacia oleracea L.) and water hyacinth (Eichhornia crassipes (Mart) Solms.) plant leaves by absorption spectra, low temperature steady_state fluorescence spectroscopy and single photon counting measurement under the same conditions. The absorption spectra at room temperature for the spinach and water hyacinth chloroplasts are similar, which show that different plants can efficiently absorb light of same wavelength. The low temperature steady_state fluorescence spectroscopy for the water hyacinth chloroplast reveals a poor balance of photon quantum between two photosystems. The fluorescence decays in PSⅡ measured at the natural Q A state for the chloroplasts have been fitted by a three_exponential kinetic model. The slow lifetime fluorescence component is assigned to a collection of associated light harvesting Chl a/b proteins, the fast lifetime component to the reaction center of PSⅡ and the middle lifetime component to the delay fluorescence of recombination of P + 680 and Pheo -. The excited energy conversion efficiency (η) in PSⅡ RC is 87% and 91% respectively for the water hyacinth and spinach chloroplasts calculated on the 20 ps model. This interesting result is not consistent with what is assumed that the efficiency is 100% in PSⅡ RC. The results in this paper also present a support for the 20 ps electron transfer time constant in PSⅡ RC. On the viewpoint of excitation energy conversion efficiency, the growing rate for the water hyacinth plan is smaller than that for the spinach plant. But, authors' results show those plants can perform highly efficient transfer of photo_excitation energy from the light_harvesting pigment system to the reaction center (approximately 100%).展开更多
Highly biocompatible superparamagnetic Fe3O4 nanoparticles were synthesized by amide of folic acid (FA) ligands and the NH2-group onto the surface of Fe3O4 nanoparticles. The as-synthesized folate-conjugated Fe3O4 n...Highly biocompatible superparamagnetic Fe3O4 nanoparticles were synthesized by amide of folic acid (FA) ligands and the NH2-group onto the surface of Fe3O4 nanoparticles. The as-synthesized folate-conjugated Fe3O4 nanoparticles were characterized by X-ray diffraction diffractometer, transmission electron microscope, FT-IR spectrometer, vibrating sample magnetometer, and dynamic light scattering instrument. The in vivo labeling effect of folate-conjugated Fe3O4 nanoparticles on the hepatoma cells was investigated in tumor-bearing rat. The results demonstrate that the as-prepared nanoparticles have cubic structure of Fe3O4 with a particle size of about 8 nm and hydrated diameter of 25.7 nm at a saturation magnetization of 51 A·m2/kg. These nanoparticles possess good physiological stability, low cytotoxicity on human skin fibroblasts and negligible effect on Wistar rats at the concentration as high as 3 mg/kg body mass. The folate-conjugated Fe3O4 nanoparticles could be effectively mediated into the human hepatoma Bel 7402 cells through the binding of folate and folic acid receptor, enhancing the signal contrast of tumor tissue and surrounding normal tissue in MRI imaging. It is in favor of the tumor cells labeling, tracing, magnetic resonance imaging (MRI) target detection and magnetic hyperthermia.展开更多
[Objective] This study aimed to investigate the mechanism of innovative montmorillonite for diarrhea treatment. [Method] Thirty healthy weanling piglets (Duroc x Landrace x Yorkshire) were randomly divided into five...[Objective] This study aimed to investigate the mechanism of innovative montmorillonite for diarrhea treatment. [Method] Thirty healthy weanling piglets (Duroc x Landrace x Yorkshire) were randomly divided into five groups and fed with basal diet, basal diet + 1 g/kg innovative montmorillonite, basal diet + 3 g/kg innovative montmorillonite, basal diet + 5 g/kg innovative montmorillonite and basal diet + 3 g/kg Bacillus subtilis microecologic agent, respectively. After four weeks, blood samples were collected via precaval vein, to detect the content of TFF3, NO and SOD in serum by ELISA kits. [Result] Compared with blank control group, the content of TFF3, NO and SOD in high-dose innovative montmorillonite group was extremely significantly increased, extremely significantly reduced and significantly in- creased, respectively; the content of TFF3 and NO in middle-dose innovative mont- morillonite group was significantly increased and significantly reduced, respectively. [Conclusion] Innovative montmorillonite may exert beneficial therapeutic actions on diarrhea by increasing TFF3 and SOD levels and decreasing NO level.展开更多
AIM: To characterise expression of known E-cadherin repressors; Snail, Slug and Twist in the development of esophageal adenocarcinoma. METHODS: E-cadherin, Slug, Snail and Twist mRNA expression in Barrett's metapl...AIM: To characterise expression of known E-cadherin repressors; Snail, Slug and Twist in the development of esophageal adenocarcinoma. METHODS: E-cadherin, Slug, Snail and Twist mRNA expression in Barrett's metaplasia and esophageal adenocarcinoma specimens was examined by real-time reverse transcription-polymerase chain reaction (RT-PCR). Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels. The effect of Slug on epithelial mesenchymal transition (EMT) markers was examined by transfection of Slug into an adenocarcinoma line OE33.RESULTS: Cellular localisation of Slug in Barrett's metaplasia was largely cytoplasmic whilst in adenocarcinoma it was nuclear. Semi-quantitative analysis indicated that Slug was more abundant in adenocarcinoma compared to matched Barrett's metaplastic specimens. Snail and Twist were expressed in adenocarcinoma but were cytoplasmic in location and not induced compared to Barrett's mucosa. These observations were supported by mRNA studies where only Slug mRNA was shown to be over-expressed in adenocarcinoma and inversely correlated to E-cadherin expression. Overexpression of Slug in OE33 mediated E-cadherin repression and induced the mesenchymal markers vimentin and fibronectin.CONCLUSION: Progression to adenocarcinoma is associated with increased Slug expression and this may represent a mechanism of E-cadherin silencing.展开更多
Objective: Chilling tolerance of salicylic acid (SA) in banana seedlings (Musa acuminata cv., Williams 8818) was investigated by changes in ultrastructure in this study. Methods: Light and electron microscope ob...Objective: Chilling tolerance of salicylic acid (SA) in banana seedlings (Musa acuminata cv., Williams 8818) was investigated by changes in ultrastructure in this study. Methods: Light and electron microscope observation. Results: Pretreatment with 0.5 mmol/L SA under normal growth conditions (30/22 ℃) by foliar spray and root irrigation resulted in many changes in ultrastructure of banana cells, such as cells separation from palisade parenchymas, the appearance of crevices in cell walls, the swelling of grana and stromal thylakoids, and a reduction in the number of starch granules. These results implied that SA treatment at 30/22 ℃ could be a type of stress. During 3 d of exposure to 7 ℃ chilling stress under low light, however, cell ultrastructure of SA-pretreated banana seedlings showed less deterioration than those of control seedlings (distilled water-pretreated). Conclusion: SA could provide some protection for cell structure of chilling-stressed banana seedling.展开更多
A three-dimensional cyclic symmetry finite element model of titanium-matrix composites(TMCs) ring was developed to investigate the stress distribution and burst failure. The effects of fiber volume fractions, reinfo...A three-dimensional cyclic symmetry finite element model of titanium-matrix composites(TMCs) ring was developed to investigate the stress distribution and burst failure. The effects of fiber volume fractions, reinforced areas, thermal residual stresses and two different temperatures on stress distribution were studied. The burst speed was obtained through analyzing the hoop tensile stresses under a series of rotating speeds. The results indicate that at the two different temperatures, the influences of fiber volume fractions and reinforced areas on stress level and distribution are different. Some proposals are provided for the structure design of the TMCs ring. With regard to thermal residual stresses, a larger reinforced area is an advisable choice for design of the ring at higher temperature.展开更多
Two contrasting cultivars of barley (Horderm vykgare L.): Kepin No. 7 (salt sensitive), and Jian 4 (salt tolerant) were grown in a hydroponics system with 2 NaCl levels: 60 mmol NaCl L-1 and 120 mmol NaCl L-1, and 3 S...Two contrasting cultivars of barley (Horderm vykgare L.): Kepin No. 7 (salt sensitive), and Jian 4 (salt tolerant) were grown in a hydroponics system with 2 NaCl levels: 60 mmol NaCl L-1 and 120 mmol NaCl L-1, and 3 Si levels: 0 mmol Si L-1, 0.5 mmol Si L-1 and 1.0 mmol Si L-1 (as silicic acid). Compared with the plants treated with 60 mmol NaCl L-1 alone, the leaf chlorophyll contents of plants treated with salt and Si increased significantly for salt-sensitive cultivar at tillering stage, but for salt-tolerant cultivar,the addition of Si resulted in an obvious increase in the leaf chlorophyll content of plants exposed to 120 mmol NaCl L-1. However, this Si-enhancement of leaf chlorophyll content was also observed in the salttolerant plants at jointing stage, but not in the salt-sensitive plants. Moreover, leaf chlorophyll content was consistently higher for the salt-tolerant cultivar than for the salt-sensitive cultivar irrespective of salt and/or Si treatment. Compared with the plants treated with salt alone, net CO2 assimilation rate in plant leaves increased significantly for both cultivars when trested with salt and Si. The addition of Si to the salt treatment was found to improve the cell ultrastructure of leaves. Under salt stress condition, the double membranes of chloroplasts disappeared, but membrane integrity was markedly improved in the salt treatment supplemented with Si. Silicon was also found to ameliorate the damage to the ultrastructure of chloroplast granae which appeared to be disintegrated and vague in salt treatments without added Si. The results support previous work which showed that Si decreases the permeability of plasma membranes of salt-stressed barley, thus mitigating salt damage.展开更多
Lutein was nano-encapsuled with hydroxypropylmethyl cellulose phthalate (HPMCP) to maintain its bioactivity and to avoid thermal/light degradation. Supercritical antisolvent precipitation was applied to prepare lute...Lutein was nano-encapsuled with hydroxypropylmethyl cellulose phthalate (HPMCP) to maintain its bioactivity and to avoid thermal/light degradation. Supercritical antisolvent precipitation was applied to prepare lutein/HPMCP nano-capsule. The effects of several operating parameters on the yield, lutein loading, encapsulation efficiency, particle size and particle size distribution of the nanocapsule were investigated. The mean diameter of nanocapsules ranged from 163 nm to 219 nm under appropriate experimental conditions. The result of scanning electron microscope showed that the nanocapsules were nearly spherical. The highest yield reached 95.35% when the initial concentration of lutein was saturated. The highest lutein loading of 15.80% and encapsulation efficiency of 88,41% were obtained under the conditions of 11 MPa, 40℃ and CHPMCP: Clutein= 5:1. The results may promote the application of lutein in food industry.展开更多
To extract vegetation pigment concentration and physiological status has been studied in two test areas covered with swamp and flourish vegetation using pushbroom hyperspectral imager (PHI) data which flied in Septemb...To extract vegetation pigment concentration and physiological status has been studied in two test areas covered with swamp and flourish vegetation using pushbroom hyperspectral imager (PHI) data which flied in September of 2000 at Daxing'anling district of Heilongjiang Province, China. The ratio analysis of reflectance spectra (RARS) indices, which were put forward by Chappelle et al (1992), are chosen in this paper owing to their effect and simpleness against both comparison with various methods and techniques for exploration of pigment concentration and characteristics of PHI data. The correlation coefficients between RARS indices and pigment concentration of vegetation were up to 0.8. The new RARS indices modes are established in the two test areas using both PHI data and spectra of different vegetations measured in the field. The indices' parameter images of chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids (Cars) of the test areas covered with swamp and flourish vegetation are acquired by the new RARS indices modes. Furthermore, the regional concentration of Chl a and Chl b are extracted and quantified using regression equations between RARS indices and pigment concentrations, which were built by Blackburn (1998). The results showed the physiological status and variety clearly, and are in good agreement with the distribution of vegetation in the field.展开更多
In order to investigate the eutrophication degree of Yuqiao Reservoir, a hybrid method, combining principal component regression (PCR) and artificial neural network (ANN), was adopted to predict chlorophyll-a concentr...In order to investigate the eutrophication degree of Yuqiao Reservoir, a hybrid method, combining principal component regression (PCR) and artificial neural network (ANN), was adopted to predict chlorophyll-a concentration of Yuqiao Reservoir’s outflow. The data were obtained from two sampling sites, site 1 in the reservoir, and site 2 near the dam. Seven water variables, namely chlorophyll-a concentration of site 2 at time t and that of both sites 10 days before t, total phosphorus(TP), total nitrogen(TN),...展开更多
AIM: To evaluate the value of endoscopic ultrasonography (EUS) in the choice of endoscopic therapy strategies for mesenchymal tumors of the upper gastrointestinal tract. METHODS: From July 2004 to September 2010, 1050...AIM: To evaluate the value of endoscopic ultrasonography (EUS) in the choice of endoscopic therapy strategies for mesenchymal tumors of the upper gastrointestinal tract. METHODS: From July 2004 to September 2010, 1050 patients with upper gastrointestinal mesenchymal tumors (GIMTs) were diagnosed using EUS. Among them, 201 patients underwent different endoscopic therapies based on the deriving layers, growth patterns and lesion sizes. RESULTS: Using EUS, we found 543 leiomyomas and 507 stromal tumors. One hundred and thirty-three leiomyomas and 24 stromal tumors were treated by snare electrosection, 6 leiomyomas and 20 stromal tumorswere treated by endoloop, 10 stromal tumors were treated by endoscopic mucosal resection and 8 stromal tumors were treated by endoscopic submucosal dissection. Complete resection of the lesion was achieved in all cases. Of the mesenchymal tumors, 90.38% diagnosed by EUS were also identified by pathohistology. All wounds were closed up nicely and no recurrence was found in the follow-up after 2 mo. CONCLUSION: EUS is an effective means of diagnosis for upper GIMTs and is an important tool in choosing the endoscopic therapy for GIMTs, by which the lesions can be treated safely and effectively.展开更多
AIM: To review 11 patients with parasitic cysts of the liver, who were treated by hepatic Iobectomy using the liver hanging maneuver (LHM).METHODS: Between January 2003 and June 2006, we retrospectively analyzed p...AIM: To review 11 patients with parasitic cysts of the liver, who were treated by hepatic Iobectomy using the liver hanging maneuver (LHM).METHODS: Between January 2003 and June 2006, we retrospectively analyzed patients who underwent surgical treatment due to parasitic cysts of the liver, at the Ege University School of Medicine, Department of General Surgery. Of these, the patients who underwent hepatic lobectomy using the LHM were reviewed and evaluated for surgical treatment outcome.RESULTS: Over a three-year period, there were 102 patients who underwent surgical treatment for parasitic cysts of the liver. Of these, 11 (10%) patients with parasitic cysts of the liver underwent hepatic Iobectomy using the LHM. Presenting symptoms were abdominal pain, dyspepsia, and cholangitis. Cyst locations were as follows: right lobe filled with cyst, 7 (63%); segmental location, 2 (18%); and multiple locations, 2 patients (18%). All patients underwent hepatic Iobectomy with an anterior approach using the LHM. The intraoperative blood transfusion requirement was one unit for 3 patients and two units for one patient. Postoperative complications included pulmonary atelectasy (2, 18%) and pleural effusion (2, 18%). No significant morbidity or mortality was observed.CONCLUSION: We concluded that hepatic Iobectomy using the LHM should be considered, not only for hepatic tumors or donor hepatectomy, but also to treat parasitic cysts of the liver.展开更多
We propose a theoretical scheme for realizing the general conditional phase shift gate of charge qubits situated in a high-Q superconducting transmission line resonator. The phase shifting angle can be tuned from 0 to...We propose a theoretical scheme for realizing the general conditional phase shift gate of charge qubits situated in a high-Q superconducting transmission line resonator. The phase shifting angle can be tuned from 0 to 27r by simply adjusting the qubit-resonator detuning and the interaction time. Based on this gate proposal, we give a detailed procedure to implement the three-qubit quantum Fourier transform with circuit quantum eleetrodynamics (QED). A careful analysis of the decoherence sources shows that the algorithm can be achieved with a high fidelity using current circuit QED techniques.展开更多
文摘The chlorophyll fluorescence parameters of Kobresia humilis Serg. and Polygonum viviparum L. grown at two different altitudes (3?200 m, 3?980 m) were measured and the ultrastructure of chloroplasts were observed for studying the photosynthetic adaptability of plants to the influences of stress conditions in alpine environment. Rfd _values, the vitality index, in leaves of K. humilis and P.viviparum grown at 3?980 m were higher than those at 3?200 m. The higher ratio of F v/F o and F v/F m in leaves of K. humilis and P.viviparum indicated that the rate of photosynthetic conversion of light energy increased at higher altitude. Ratios of F v/F o and F v/F m and Rfd _values in K.humilis were higher than that in P.viviparum grown at the same altitude. There were more irregular chloroplasts in leaves of both species grown at higher altitude. Many irregular chloroplasts such as swollen thylakoid, deformed chloroplast envelope, were observed in P.viviparum grown at 3?980 m, but few in K. humilis . These results were discussed in relation to the photosynthetic adaptability of alpine plants and the different adaptive competence between K.humilis and P.viviparum .
文摘Wheat ( Triticum aestivum L.) plants were grown under ambient and doubled_CO 2(plus 350 μL/L) concentration in cylindrical open_top chamber to examine their effects on the ultrastructure, supramolecular architecture, absorption spectrum and low temperature (77 K) fluorescence emission spectrum of the chloroplasts from wheat leaves. The results were briefly summarized as follows: (1) The wheat leaves possessed normally developed chloroplasts with intact grana and stroma thylakoid membranes; The grana intertwined with stroma thylakoid membranes and increased slightly in stacking degree and the width of granum, in spite of more accumulated starch grains within the chloroplasts than those in control; (2) The particle density in the stacked region of the endoplasmic fracture face (EFs) and protoplasmic fracture face (PFs) and in the unstacked region the endoplasmic fracture face (EFu) and the protoplasmic fracture face (PFu) was significantly higher than that of control. Furthermore, in some cases many more particles on EFs faces of thylakoid membranes appeared as a paracrystalline particle array; (3) The variations in the structure of chloroplasts were consistent with the absorption spectra and the low temperature (77 K) fluorescence emission spectra of the chloroplasts developed under the doubled_CO 2 concentration. Results indicate that the capability of light energy absorption of chloroplasts and regulative capability of excitation energy distribution between PSⅡ and PSⅠ were raised by doubled_CO 2 concentration. This is very favorable for final productivity of wheat.
基金supported by the National Natural Science Foundation of China (Project No: 30371156)Research Foundation of Jiangsu Province (Project No: BG2006314)
文摘The ultrastructural distribution and active location of ATPase and the ultrastructural variations were investigated in mesophyll cells of Cyclocarya paliurus seedlings after iso-osmotic salt/water treatments in combination with calcium regulation. C. paliurus seed- lings were treated with five groups (control, 85 mM NaCl, 85 mM NaCl+ 12 mM Ca(NO3)2, PEG iso-osmotic to 85 mM NaCl and PEG iso-osmotic to 85 mM NaCl+12 mM Ca(NO))2) in a hydroponic system in a phytotron. Results show that under normal growth conditions the ATPase activity was low and the enzyme was primarily located on the nucleus. After 12 days of iso-osmotic salt/water treatments, ATPase activity on the tonoptast increased. Osmiophilic globules for iso-osmotic water treatment were greater than that for iso-osmotie salt treatments. The ATPase activity increased and was mostly transferred onto the nucleus for calcium regulation treatment under iso- osmotic salt/water stresses, and the osmiophilic globules significantly decreased under iso-osmotic water stress with calcium regulation. The ATPase located on the nucleus indicated that the degree of salt/drought damage that seedlings suffered was slighter, while the amount of the enzyme located on the tonoplast showed that the degree of salt/drought damage there was more serious. After 4 and 20 days of iso- osmotic treatments, the injury suffered by the leaf ultrastructures of C. paliurus seedlings for iso-osmotic treatment with calcium regula- tion was lower than those without calcium regulation, especially for the iso-osmotic water treatments. Preliminary analysis suggests that the iniury suffered by C. paliurus seedlings was lower for iso-osmotic salt treatments than for iso-osmotic water treatments, while the effect of calcium regulation under iso-osmotic water stress was greater than that of the iso-osmotic salt stress.
文摘With the development of the multicellular nodules in the leaves of Hypericum per plastids increased both in number and volume, and some plastids degenerated and were surrounded by dark tubular elements and vesicles. Some vesicles fused with vacuoles and secreted substances into vacuoles. There are many multivesicles, multimembrane structures and osmiophilic droplets in vacuoles of nodule cells. Meanwhile, dictyosome secreted vesicles into the vacuoles. However, there is a large central vacuole completely filled with secretory materials (hypericin) in matured multicellular nodules. This suggests that the osmiophilic droplets may be a precursor of hypericin originated from the degenerated plastids. There were abundant endoplasmic reticulums and dictyosomes between the plastids and osmiophilic droplets, suggesting that they may be involved in the synthesis and/or transport of the precursor of hypericin.
文摘The authors have studied the spectroscopic characteristics and the fluorescence lifetime for the chloroplasts from spinach (Spinacia oleracea L.) and water hyacinth (Eichhornia crassipes (Mart) Solms.) plant leaves by absorption spectra, low temperature steady_state fluorescence spectroscopy and single photon counting measurement under the same conditions. The absorption spectra at room temperature for the spinach and water hyacinth chloroplasts are similar, which show that different plants can efficiently absorb light of same wavelength. The low temperature steady_state fluorescence spectroscopy for the water hyacinth chloroplast reveals a poor balance of photon quantum between two photosystems. The fluorescence decays in PSⅡ measured at the natural Q A state for the chloroplasts have been fitted by a three_exponential kinetic model. The slow lifetime fluorescence component is assigned to a collection of associated light harvesting Chl a/b proteins, the fast lifetime component to the reaction center of PSⅡ and the middle lifetime component to the delay fluorescence of recombination of P + 680 and Pheo -. The excited energy conversion efficiency (η) in PSⅡ RC is 87% and 91% respectively for the water hyacinth and spinach chloroplasts calculated on the 20 ps model. This interesting result is not consistent with what is assumed that the efficiency is 100% in PSⅡ RC. The results in this paper also present a support for the 20 ps electron transfer time constant in PSⅡ RC. On the viewpoint of excitation energy conversion efficiency, the growing rate for the water hyacinth plan is smaller than that for the spinach plant. But, authors' results show those plants can perform highly efficient transfer of photo_excitation energy from the light_harvesting pigment system to the reaction center (approximately 100%).
基金Project(2011JQ028)supported by the Fundamental Research Funds for the Central Universities,ChinaProjects(2008SK3114,2010SK3113)supported by Hunan Provincial Science&Technology Plan,China+2 种基金Project(B2007086)supported by Science&Research Funds of Hunan Health Department,ChinaProject(12JJ5057)supported by Natural Science Foundation of Hunan Province,ChinaProjects(XCX1119,XCX12073)supported by University Students Innovative Experiment Plan Project of Hunan Agricultural University,China
文摘Highly biocompatible superparamagnetic Fe3O4 nanoparticles were synthesized by amide of folic acid (FA) ligands and the NH2-group onto the surface of Fe3O4 nanoparticles. The as-synthesized folate-conjugated Fe3O4 nanoparticles were characterized by X-ray diffraction diffractometer, transmission electron microscope, FT-IR spectrometer, vibrating sample magnetometer, and dynamic light scattering instrument. The in vivo labeling effect of folate-conjugated Fe3O4 nanoparticles on the hepatoma cells was investigated in tumor-bearing rat. The results demonstrate that the as-prepared nanoparticles have cubic structure of Fe3O4 with a particle size of about 8 nm and hydrated diameter of 25.7 nm at a saturation magnetization of 51 A·m2/kg. These nanoparticles possess good physiological stability, low cytotoxicity on human skin fibroblasts and negligible effect on Wistar rats at the concentration as high as 3 mg/kg body mass. The folate-conjugated Fe3O4 nanoparticles could be effectively mediated into the human hepatoma Bel 7402 cells through the binding of folate and folic acid receptor, enhancing the signal contrast of tumor tissue and surrounding normal tissue in MRI imaging. It is in favor of the tumor cells labeling, tracing, magnetic resonance imaging (MRI) target detection and magnetic hyperthermia.
基金Supported by Agricultural Science and Technology Independent Innovation Fund of Jiangsu Province(CX(13)5030)~~
文摘[Objective] This study aimed to investigate the mechanism of innovative montmorillonite for diarrhea treatment. [Method] Thirty healthy weanling piglets (Duroc x Landrace x Yorkshire) were randomly divided into five groups and fed with basal diet, basal diet + 1 g/kg innovative montmorillonite, basal diet + 3 g/kg innovative montmorillonite, basal diet + 5 g/kg innovative montmorillonite and basal diet + 3 g/kg Bacillus subtilis microecologic agent, respectively. After four weeks, blood samples were collected via precaval vein, to detect the content of TFF3, NO and SOD in serum by ELISA kits. [Result] Compared with blank control group, the content of TFF3, NO and SOD in high-dose innovative montmorillonite group was extremely significantly increased, extremely significantly reduced and significantly in- creased, respectively; the content of TFF3 and NO in middle-dose innovative mont- morillonite group was significantly increased and significantly reduced, respectively. [Conclusion] Innovative montmorillonite may exert beneficial therapeutic actions on diarrhea by increasing TFF3 and SOD levels and decreasing NO level.
基金Supported by City Hospital Trust Fundthe University of Birmingham Scientific Project Grant
文摘AIM: To characterise expression of known E-cadherin repressors; Snail, Slug and Twist in the development of esophageal adenocarcinoma. METHODS: E-cadherin, Slug, Snail and Twist mRNA expression in Barrett's metaplasia and esophageal adenocarcinoma specimens was examined by real-time reverse transcription-polymerase chain reaction (RT-PCR). Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels. The effect of Slug on epithelial mesenchymal transition (EMT) markers was examined by transfection of Slug into an adenocarcinoma line OE33.RESULTS: Cellular localisation of Slug in Barrett's metaplasia was largely cytoplasmic whilst in adenocarcinoma it was nuclear. Semi-quantitative analysis indicated that Slug was more abundant in adenocarcinoma compared to matched Barrett's metaplastic specimens. Snail and Twist were expressed in adenocarcinoma but were cytoplasmic in location and not induced compared to Barrett's mucosa. These observations were supported by mRNA studies where only Slug mRNA was shown to be over-expressed in adenocarcinoma and inversely correlated to E-cadherin expression. Overexpression of Slug in OE33 mediated E-cadherin repression and induced the mesenchymal markers vimentin and fibronectin.CONCLUSION: Progression to adenocarcinoma is associated with increased Slug expression and this may represent a mechanism of E-cadherin silencing.
基金Project (No. 30471112) supported by the National Natural Science Foundation of China
文摘Objective: Chilling tolerance of salicylic acid (SA) in banana seedlings (Musa acuminata cv., Williams 8818) was investigated by changes in ultrastructure in this study. Methods: Light and electron microscope observation. Results: Pretreatment with 0.5 mmol/L SA under normal growth conditions (30/22 ℃) by foliar spray and root irrigation resulted in many changes in ultrastructure of banana cells, such as cells separation from palisade parenchymas, the appearance of crevices in cell walls, the swelling of grana and stromal thylakoids, and a reduction in the number of starch granules. These results implied that SA treatment at 30/22 ℃ could be a type of stress. During 3 d of exposure to 7 ℃ chilling stress under low light, however, cell ultrastructure of SA-pretreated banana seedlings showed less deterioration than those of control seedlings (distilled water-pretreated). Conclusion: SA could provide some protection for cell structure of chilling-stressed banana seedling.
基金Projects(51071122,51271147,51201134)supported by the National Natural Science Foundation of ChinaProject(3102014JCQ01023)supported by the Fundamental Research Funds for the Central UniversitiesProject(115-QP-2014)supported by the Research Fund of the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University,China
文摘A three-dimensional cyclic symmetry finite element model of titanium-matrix composites(TMCs) ring was developed to investigate the stress distribution and burst failure. The effects of fiber volume fractions, reinforced areas, thermal residual stresses and two different temperatures on stress distribution were studied. The burst speed was obtained through analyzing the hoop tensile stresses under a series of rotating speeds. The results indicate that at the two different temperatures, the influences of fiber volume fractions and reinforced areas on stress level and distribution are different. Some proposals are provided for the structure design of the TMCs ring. With regard to thermal residual stresses, a larger reinforced area is an advisable choice for design of the ring at higher temperature.
文摘Two contrasting cultivars of barley (Horderm vykgare L.): Kepin No. 7 (salt sensitive), and Jian 4 (salt tolerant) were grown in a hydroponics system with 2 NaCl levels: 60 mmol NaCl L-1 and 120 mmol NaCl L-1, and 3 Si levels: 0 mmol Si L-1, 0.5 mmol Si L-1 and 1.0 mmol Si L-1 (as silicic acid). Compared with the plants treated with 60 mmol NaCl L-1 alone, the leaf chlorophyll contents of plants treated with salt and Si increased significantly for salt-sensitive cultivar at tillering stage, but for salt-tolerant cultivar,the addition of Si resulted in an obvious increase in the leaf chlorophyll content of plants exposed to 120 mmol NaCl L-1. However, this Si-enhancement of leaf chlorophyll content was also observed in the salttolerant plants at jointing stage, but not in the salt-sensitive plants. Moreover, leaf chlorophyll content was consistently higher for the salt-tolerant cultivar than for the salt-sensitive cultivar irrespective of salt and/or Si treatment. Compared with the plants treated with salt alone, net CO2 assimilation rate in plant leaves increased significantly for both cultivars when trested with salt and Si. The addition of Si to the salt treatment was found to improve the cell ultrastructure of leaves. Under salt stress condition, the double membranes of chloroplasts disappeared, but membrane integrity was markedly improved in the salt treatment supplemented with Si. Silicon was also found to ameliorate the damage to the ultrastructure of chloroplast granae which appeared to be disintegrated and vague in salt treatments without added Si. The results support previous work which showed that Si decreases the permeability of plasma membranes of salt-stressed barley, thus mitigating salt damage.
基金Supported by the National High Technology Research and Development Program of China(2007AA10Z350)
文摘Lutein was nano-encapsuled with hydroxypropylmethyl cellulose phthalate (HPMCP) to maintain its bioactivity and to avoid thermal/light degradation. Supercritical antisolvent precipitation was applied to prepare lutein/HPMCP nano-capsule. The effects of several operating parameters on the yield, lutein loading, encapsulation efficiency, particle size and particle size distribution of the nanocapsule were investigated. The mean diameter of nanocapsules ranged from 163 nm to 219 nm under appropriate experimental conditions. The result of scanning electron microscope showed that the nanocapsules were nearly spherical. The highest yield reached 95.35% when the initial concentration of lutein was saturated. The highest lutein loading of 15.80% and encapsulation efficiency of 88,41% were obtained under the conditions of 11 MPa, 40℃ and CHPMCP: Clutein= 5:1. The results may promote the application of lutein in food industry.
文摘To extract vegetation pigment concentration and physiological status has been studied in two test areas covered with swamp and flourish vegetation using pushbroom hyperspectral imager (PHI) data which flied in September of 2000 at Daxing'anling district of Heilongjiang Province, China. The ratio analysis of reflectance spectra (RARS) indices, which were put forward by Chappelle et al (1992), are chosen in this paper owing to their effect and simpleness against both comparison with various methods and techniques for exploration of pigment concentration and characteristics of PHI data. The correlation coefficients between RARS indices and pigment concentration of vegetation were up to 0.8. The new RARS indices modes are established in the two test areas using both PHI data and spectra of different vegetations measured in the field. The indices' parameter images of chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids (Cars) of the test areas covered with swamp and flourish vegetation are acquired by the new RARS indices modes. Furthermore, the regional concentration of Chl a and Chl b are extracted and quantified using regression equations between RARS indices and pigment concentrations, which were built by Blackburn (1998). The results showed the physiological status and variety clearly, and are in good agreement with the distribution of vegetation in the field.
文摘In order to investigate the eutrophication degree of Yuqiao Reservoir, a hybrid method, combining principal component regression (PCR) and artificial neural network (ANN), was adopted to predict chlorophyll-a concentration of Yuqiao Reservoir’s outflow. The data were obtained from two sampling sites, site 1 in the reservoir, and site 2 near the dam. Seven water variables, namely chlorophyll-a concentration of site 2 at time t and that of both sites 10 days before t, total phosphorus(TP), total nitrogen(TN),...
文摘AIM: To evaluate the value of endoscopic ultrasonography (EUS) in the choice of endoscopic therapy strategies for mesenchymal tumors of the upper gastrointestinal tract. METHODS: From July 2004 to September 2010, 1050 patients with upper gastrointestinal mesenchymal tumors (GIMTs) were diagnosed using EUS. Among them, 201 patients underwent different endoscopic therapies based on the deriving layers, growth patterns and lesion sizes. RESULTS: Using EUS, we found 543 leiomyomas and 507 stromal tumors. One hundred and thirty-three leiomyomas and 24 stromal tumors were treated by snare electrosection, 6 leiomyomas and 20 stromal tumorswere treated by endoloop, 10 stromal tumors were treated by endoscopic mucosal resection and 8 stromal tumors were treated by endoscopic submucosal dissection. Complete resection of the lesion was achieved in all cases. Of the mesenchymal tumors, 90.38% diagnosed by EUS were also identified by pathohistology. All wounds were closed up nicely and no recurrence was found in the follow-up after 2 mo. CONCLUSION: EUS is an effective means of diagnosis for upper GIMTs and is an important tool in choosing the endoscopic therapy for GIMTs, by which the lesions can be treated safely and effectively.
文摘AIM: To review 11 patients with parasitic cysts of the liver, who were treated by hepatic Iobectomy using the liver hanging maneuver (LHM).METHODS: Between January 2003 and June 2006, we retrospectively analyzed patients who underwent surgical treatment due to parasitic cysts of the liver, at the Ege University School of Medicine, Department of General Surgery. Of these, the patients who underwent hepatic lobectomy using the LHM were reviewed and evaluated for surgical treatment outcome.RESULTS: Over a three-year period, there were 102 patients who underwent surgical treatment for parasitic cysts of the liver. Of these, 11 (10%) patients with parasitic cysts of the liver underwent hepatic Iobectomy using the LHM. Presenting symptoms were abdominal pain, dyspepsia, and cholangitis. Cyst locations were as follows: right lobe filled with cyst, 7 (63%); segmental location, 2 (18%); and multiple locations, 2 patients (18%). All patients underwent hepatic Iobectomy with an anterior approach using the LHM. The intraoperative blood transfusion requirement was one unit for 3 patients and two units for one patient. Postoperative complications included pulmonary atelectasy (2, 18%) and pleural effusion (2, 18%). No significant morbidity or mortality was observed.CONCLUSION: We concluded that hepatic Iobectomy using the LHM should be considered, not only for hepatic tumors or donor hepatectomy, but also to treat parasitic cysts of the liver.
基金Supported by the Foundation for the Author of National Excellent Doctoral Dissertation of China under Grant No. 200524the Program for New Century Excellent Talents of China under Grant No. 06-0920
文摘We propose a theoretical scheme for realizing the general conditional phase shift gate of charge qubits situated in a high-Q superconducting transmission line resonator. The phase shifting angle can be tuned from 0 to 27r by simply adjusting the qubit-resonator detuning and the interaction time. Based on this gate proposal, we give a detailed procedure to implement the three-qubit quantum Fourier transform with circuit quantum eleetrodynamics (QED). A careful analysis of the decoherence sources shows that the algorithm can be achieved with a high fidelity using current circuit QED techniques.