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ABSTRACT: Vascular hyporeactivity played an important role in many critical illness including shock or sepsis, but the mechanisms are incompletely understood. The objective of the present study was to investigate the roles of major mitogen-activated protein kinases (MAPKs extracellular signal-regulated kinase [ERK], p38 MAPK, and jun NH2-terminal kinase [JNK]) on vascular reactivity and the mechanisms.
With superior mesenteric arteries from hemorrhagic shock rats, the role of p38 MAPK, ERK, and JNK in the regulation of vascular reactivity following shock and their relationship to myosin light chain (MLC20) phosphorylation-dependent pathway was observed.
ERK, p38 MAPK, and JNK activities in superior mesenteric arteries were increased at early shock and decreased at late shock. Stimulation of MAPKs with angiotensin II (AngII) increased the vascular reactivity, calcium sensitivity, and MLC20 phosphorylation. The increasing effect of AngII on vascular reactivity was antagonized by ERK, p38 MAPK, and JNK inhibitors, while the effect of AngII on calcium sensitivity was only blocked by ERK and p38 MAPK inhibitor, but not by JNK inhibitor. AngII increased the activity of protein kinase C-dependent phosphatase inhibitor of 17-kD (CPI17), integrin-linked kinase (ILK), and zipper-interacting protein kinase (ZIPK), The effect of AngII on CPI17 was blocked by ERK and p38 MAPK inhibitor, while the effect of AngII on ILK and ZIPK was only blocked by ERK inhibitor.
MAPKs participated in the regulation of vascular reactivity during shock. ERK and p38 MAPK is mainly through ILK, ZIPK, and CPI17-mediated MLC20 phosphorylation-dependent pathway, while JNK may be involved in the regulation of vascular reactivity by other mechanisms.
The journal of trauma and acute care surgery. 04/2013; 74(4):1033-43.
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ABSTRACT: A novel aroA gene encoding 5-enolpyruvylshikimate-3-phosphate synthase from Bacillus cereus was identified and overexpressed by genomic library construction and complementary screening. The enzyme was then purified to homogeneity. We also transformed the aroA ( B. cereus ) gene into Arabidopsis thaliana by a floral dip method, and demonstrated that transgenic A. thaliana plants exhibited significant glyphosate resistance compared with the wild type. These results strongly suggested that the strategy was highly efficient and advantageous for rapidly cloning aroA genes from microorganisms in natural environments.
MIRCEN Journal of Applied Microbiology and Biotechnology 11/2012; · 1.08 Impact Factor
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ABSTRACT: Nanosized copper particles (nano-Cu), one of the representative metal nanometer materials, were used in several domains, and the potential toxicity was raised more and more attention. In order to investigate the cytotoxicity induced by nano-Cu in podocytes, which was the key player of the glomerular filtration barrier, podocytes were treated with different concentrations of nano-Cu. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to measure the cell viability. Hoechst 33342 staining assay and Annexin V/PI double labeling assay were used to identify whether the cytotoxicity induced by nano-Cu was due to apoptosis or necrosis. The oxidative stress induced by nano-Cu and its mechanism were studied in relation to the generation of reactive oxygen species (ROS), superoxide dismutase (SOD) and malondialdehyde (MDA). As a result, while podocytes were treated with nano-Cu, the cell viability was significantly decreased and the apoptosis was significantly increased in podocytes. Results showed that nano-Cu affected the oxidant-antioxidant balance and had cytotoxicity in podocytes, resulting in the enhanced generation of ROS and MDA. Meanwhile, pretreatment with N-(2-mercaptopropionyl)-glycine (N-MPG), a type of ROS scavenger, could inhibit podocyte apoptosis induced by nano-Cu. Results suggested that the increased oxidative stress was a key mechanism in the podocyte apoptosis induced by nano-Cu, which could provide evidence for further research on the toxicity of nano-Cu.
Journal of hazardous materials 09/2012; · 4.14 Impact Factor
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ABSTRACT: Nanosized copper oxide (nano-CuO) has been widely used in many fields. Recent studies have shown that nano-CuO has toxic effects on various organs, but the effects of nano-CuO on kidney remain unclear. The aim of this study was to assess whether nano-CuO can induce the apoptosis of podocytes. The result of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay indicated that nano-CuO decreased podocyte viability in a concentration-dependent and time-dependent manner. The apoptotic assay by flow cytometry showed that nano-CuO induced podocyte apoptosis significantly. Meanwhile, the result of flow cytometric assay gave a clear indication that nano-CuO increased reactive oxygen species (ROS) level. The measurement of superoxide dismutase (SOD) and malondialdehyde (MDA) showed that nano-CuO decreased SOD and increased MDA levels in podocytes. These results may provide basic information for the safe application of nano-CuO in the future.
Archive für Toxikologie 08/2012; · 4.67 Impact Factor
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Hyo-Sang Lee,
Hong Ma,
Rita Cervera Juanes,
Masahito Tachibana,
Michelle Sparman,
Joy Woodward,
Cathy Ramsey, Jing Xu,
Eun-Ju Kang,
Paula Amato,
Georg Mair,
Ralf Steinborn,
Shoukhrat Mitalipov
[show abstract]
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ABSTRACT: The timing and mechanisms of mitochondrial DNA (mtDNA) segregation and transmission in mammals are poorly understood. Genetic bottleneck in female germ cells has been proposed as the main phenomenon responsible for rapid intergenerational segregation of heteroplasmic mtDNA. We demonstrate here that mtDNA segregation occurs during primate preimplantation embryogenesis resulting in partitioning of mtDNA variants between daughter blastomeres. A substantial shift toward homoplasmy occurred in fetuses and embryonic stem cells (ESCs) derived from these heteroplasmic embryos. We also observed a wide range of heteroplasmic mtDNA variants distributed in individual oocytes recovered from these fetuses. Thus, we present here evidence for a previously unknown mtDNA segregation and bottleneck during preimplantation embryo development, suggesting that return to the homoplasmic condition can occur during development of an individual organism from the zygote to birth, without a passage through the germline.
Cell reports. 05/2012; 1(5):506-15.
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ABSTRACT: Carbon free LiFe1−x
Mn
x
PO4 (x=0, 0.05, 0.1, 0.2, 0.4) cathode materials were prepared by a direct-hydrothermal process at 170°C for 10h. The structural
and electrochemical properties of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy
(SEM), charge–discharge experiments, cyclic voltammetry (CV) and alternating current (AC) impedance spectroscopy. The electrochemical
performance of LiFePO4 prepared in this manner showed to be positively affected by Mn2+-substitution. Among the Mn2+-substitution samples, the LiFe0.9Mn0.1PO4 exhibited an initial discharge capacity of 141.4mAhg−1 at 0.1 C, and the capacity fading is only 2.7% after 50 cycles.
KeywordsLiFePO4
-Hydrothermal process-Mn2+ substitution
Journal of Applied Electrochemistry 05/2012; 40(3):575-580. · 1.75 Impact Factor
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ABSTRACT: Seedlings of Camellia sinensis (L.) were grown hydroponically to study the effect of aluminium (Al) on leaf antioxidant defence system and cell ultrastructure.
We found that malondialdehyde (MDA) content decreased at 0–0.32mM Al, but increased significantly at 0.53mM Al. Like MDA,
hydrogen peroxide (H2O2) content increased at 0.53mM Al; however, no differences were observed at 0–0.32mM Al. Superoxide dismutase (SOD, EC1.15.1.1)
activity remained practically constant at 0–0.32mM Al, but increased sharply at 0.53mM Al; catalase (CAT, EC1.11.1.6) and
guaiacol peroxidase (GPX, EC1.11.1.7) activities decreased following an initial increase, reaching their peaks at 0.32mM
Al. Ascorbate peroxidase (APX, EC 1.11.1.11) activity increased and glutathione (GR, EC 1.6.4.2) level fluctuated with increasing
Al concentrations. Transmission electron microscope analysis of Al-treated leaves showed that although cell ultrastructural
integrity was maintained at 0–0.32mM, significant membrane damage was observed at 0.53mM. Our results suggest that at low
Al concentrations, the leaf antioxidant defence system can scavenge reactive oxygen species and sufficiently protect cells
from free radical injury. However, at higher Al concentrations (0.53mM), the balance between formation and detoxification
of ROS is lost, resulting in the destruction of cell ultrastructure.
KeywordsAluminium–Antioxidant enzymes–
Camellia sinensis (L.)–Leaf ultrastructure–Reactive oxygen species
Acta Physiologiae Plantarum 05/2012; 33(3):973-978. · 1.64 Impact Factor
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ABSTRACT: The aging mechanism of SBS modified asphalt during its aging process was studied. The characterizations of base asphalt, SBS
polymer and its modified asphalt were determined in different aging time by Fourier transform infrared spectrum (FTIR). FTIR
shows that oxidative dehydrogenation reaction occurs in asphalt, and unsaturated carbon bond is generated under short-term
thermal aging condition. Additionally, SBS polymer was aged significantly under that condition, the speed of which was faster
than that of base asphalt. The aging laws of both asphalt and SBS polymer during the aging process of SBS modified asphalt
were similar to their aging laws respectively. Due to the protective effect between asphalt and SBS polymer, the aging degrees
of asphalt and SBS polymer were lower than those aged independently.
Key wordsSBS polymer modified asphalt-aging-FTIR
Journal of Wuhan University of Technology-Mater Sci Ed 05/2012; 25(6):1047-1052. · 0.35 Impact Factor
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ABSTRACT: The influence of male age on female mate preference and reproductive performance in the cabbage beetle, Colaphellus bowringi was examined, using male and female adults of varying ages (young, middle-aged and old) after a single mating. In a simultaneous
choice test, females of all age class preferentially mated with middle-aged males. Mating duration was positively related
to male age. Longevity of females was not significantly affected by male age. Young females paired to middle-aged males had
significantly higher egg production than those paired to old males, and the eggs of females paired to middle-aged males exhibited
significantly higher hatching success than the eggs of females mated to young or old males. These results suggest that middle-aged
males are more advantageous for female fitness than young and old males.
KeywordsMale age–
Colaphellus bowringi
–female mate preference–mating duration–longevity–fecundity–fertility
Journal of Insect Behavior 04/2012; 24(2):83-93. · 0.96 Impact Factor
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ABSTRACT: The effect of hydroxamic acid starch (HAS) and hydroxamic acid polyacrylamide (HPAM) on the flotation of diaspore and kaolinite
was investigated by flotation test. It is found that HAS depresses diaspore but activates kaolinite in acidic pulp, while
HPAM activates both diaspore and kaolinite in the pH range of 2.0–10.5. The measurement of zeta potential shows that both
HAS and HPAM can increase zeta potential of negatively charged diaspore, which indicates the existence of chemical bonding
or hydrogen bonding between the reagents and diaspore. By covering the collector dodecyl amine (DDA) on diaspore surface,
HAS increases the hydrophilicity of minerals and depresses the flotation of diaspore, however HPAM activates the flotation
of diaspore by increasing the adsorption of DDA on diaspore surface.
Journal of Central South University of Technology 04/2012; 11(3):291-294. · 0.36 Impact Factor
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ABSTRACT: The behavior of a new type of secondary anode material made of carbon fiber reinforced cement used for cathodic protection
of steel in concrete was studied. The mechanical, electrical and electrochemical properties of this conductive mortar were
investigated. Results indicate that the addition of carbon fiber enhances the strength and ductility of the mortar, as well
as the electrical property. The anodic polarization behavior was tested on specimens immersed in aqueous solutions of saturated
Ca(OH)2 in the presence or absence of 3% NaCl. Based on impedance measurements the electrochemical parameters of conductive mortar
were calculated. It is shown that the investigated conductive mortar can be used in cathodic protection of reinforced concrete.
The study also shows that the optimum fiber content in mortar should be in the range from 0.5 vol% to 0.7 vol%.
Key wordsreinforced concrete-cathodic protection-EIS-electrochemical property
Journal of Wuhan University of Technology-Mater Sci Ed 04/2012; 25(5):883-888. · 0.35 Impact Factor
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ABSTRACT: To overcome the peak band broadening and to increase the peak capacity and separation efficiency of a two-dimensional liquid
chromatographic system, a high-temperature normal phase liquid chromatography (HTNPLC) was used as the first dimension (1st-D), and a RPLC was used as the second dimension (2nd-D). The sample was first separated on the 1st-D CN column and the primary eluent stored in the sampling-loop system alternatively (in HTNPLC×RPLC mode) or selectively
(in HTNPLC/RPLC mode) and was then transferred to 2nd-D C18 column for further separation. The resolution and separation efficiency of the systems were greatly improved. The systems
were evaluated by analyzing several polycyclic aromatic hydrocarbons and Glycyrrhiza uralensis extract.
Frontiers of Chemistry in China 04/2012; 4(2):196-201.
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ABSTRACT: The vascular reactivity and calcium sensitivity were decreased following hemorrhagic shock. Arginine vasopressin (AVP) was
beneficial to endotoxic, infectious/spetic and hemorrhagic shock. Our previous studies found that Rho kinase played an important
role in the occurrence of calcium desensitization following shock. It was reported that AVP was with stimulation effect of
Rho kinase. So we hypothesized that AVP might have beneficial effect on shock via activation of Rho kinase to regulate the
calcium sensitivity and vascular reactivity. Hemorrhagic shock (40 mmHg for 2 h) Wistar rats in vivo were adopted to observe the effects of small dose of AVP on hemodynamics, 24-h survival rate, the pressor effect of norepinephrine
(NE) and the contractility of superior mesenteric artery (SMA). Isolated SMAs from hemorrhagic shock rats were adopted to
observe the effects of AVP on vascular reactivity and calcium sensitivity and its relationship to Rho kinase with an isolated
organ perfusion system. The results show that AVP at the concentration of 0.1 U/kg and 0.4 U/kg significantly improved the
hemodynamic parameters and the 24-h survival rate of hemorrhagic shock rats. Meanwhile, these dosages of AVP significantly
increased the pressor effect of NE and the contractile response of SMA to NE. Y-27632 (3 μg/kg), a Rho kinase specific inhibitor,
abolished the beneficial effects of AVP. In vitro, the calcium sensitivity and vascular reactivity of SMA to calcium and NE were significantly decreased following hemorrhagic
shock. AVP at the concentration of 0.5 nmol/L and 5 nmol/L significantly increased the calcium sensitivity and vascular reactivity.
These effects of AVP were abolished by Y-27632 (10 μmol/L). Taken together, the results suggest that AVP at 0.1 U/kg and 0.4
U/kg is beneficial to hemorrhagic shock by improving the vascular reactivity, which involves activation of Rho kinase.
Frontiers of Medicine in China 04/2012; 2(3):248-254.
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ABSTRACT: The R2R3-Myb proteins comprise a large family of plant transcription factors that regulate the expression of multiple drought-responsive
and cold-responsive genes by binding special cis-elements at the promoter. There have been previous studies in transgenic
plant over-expression of the myb protein. In this article, we analyzed the function of MdMYB6, an R2R3-type Myb transcription factor from apples (Malus × domestica), in transgenic Arabidopsis plants. In contrast to
wild type plants, these transgenic lines accumulated less anthocyanin. Equimolar concentrations of sorbitol did not alter
the anthocyanin accumulation. Real-time polymerase chain reaction (PCR) indicated that MdMYB6 over-expression suppressed enzymes involved in anthocyanin biosynthesis and some Arabidopsis basic helix-loop-helix (bHLH)
genes. The MdMYB6 transcription faction may be an important repressor of anthocyanin biosynthesis in plants.
Keywords
MdMYB6
–Anthocyanins–BHLH–Sucrose–MYB
Plant Cell Tissue and Organ Culture 04/2012; 106(2):235-242. · 3.09 Impact Factor
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ABSTRACT: A biocomposite film for sensing hydrogen peroxide (HP) is described that is based on nanospheres made from hemoglobin (Hb),
graphene, and zinc oxide. The composition, morphology and size of the film were studied by transmission electron microscopy.
UV-vis spectroscopy revealed that the Hb entrapped in the graphene and ZnO nanosphere retains its native structure. A pair
of stable and well-defined quasi-reversible redox peaks of Hb was obtained, with a formal potential of −30mV at pH 6.5. Hb
exhibits excellent long-term bioelectrocatalytic activity towards HP. The apparent heterogeneous electron transfer rate constant
is 1.0s−1, indicating that the presence of graphene in the composite film facilitates the electron transfer between matrix and the
electroactive center of Hb. The sensor responds linearly to HP in the range from 1.8μM to 2.3mM, with a detection limit
of 0.6μM (at S/N = 3). The apparent Michaelis-Menten constant is 1.46mM. The biosensor displays high sensitivity, good reproducibility,
and long-term stability.
FigureTEM images of graphene insert: graphene-ZnO nanosphere
KeywordsGraphene–ZnO nanosphere–Biosensor–Direct electron transfer–Hemoglobin
Microchimica Acta 04/2012; 172(3):425-430. · 3.03 Impact Factor
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ABSTRACT: We applied invitro mutagenesis and colony screening, using the wild type phyI1s gene from Aspergillus niger 113 as the template, and obtained two mutant phyI1s (gene products) after one round of screening. The two mutants had mutations
at two nucleic acid sites, resulting in changes in two amino acids: K41E, E121F. None of the amino acid substitutions in the
two mutants was in a position reported to be important for catalysis or substrate binding. Kinetic analysis of the phytase
activity of the two mutants indicated that the substitutions gave rise to 2.5- and 3.1-fold increased specific activity, and
a 1.78- and 3.24-fold reduced affinity for sodium phytate. In addition, the overall catalytic efficiency (k
cat/K
m) of the two mutants was changed by 0.52-fold and 0.68-fold compared to that of the wild type. Such mutants will be instrumental
for the structure–function study of the enzyme and for industrial application.
KeywordsEnzyme activity-
phyI1s gene-Phytase-Structure–function analysis
World Journal of Microbiology and Biotechnology 04/2012; 26(5):903-907. · 1.53 Impact Factor
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ABSTRACT: Carbon fiber-reinforced cement is a multifunctional composite material owing to its conductive behavior. This article presents
a model for quantitative analysis of the conductive mechanism. The model is based on the concept that the electronic conduction
dominates when the composite is in dry state and is a combination of ohmic continuum conduction and tunnel transmission conduction.
Therefore, Ohm’s law and tunneling effect theory are employed in the modeling process. Validity of the model has been confirmed
by comparison of the calculated and measured results. Furthermore, the model is applied in simulating the strain sensing characteristics.
Numerical results are shown and compared with measured data obtained under compressive loading. The agreement between theoretical
and experimental results provides further support to the model.
Journal of Materials Science 04/2012; 45(13):3538-3546. · 2.02 Impact Factor
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ABSTRACT: Transparent electronics has attracted great research efforts in recent years due to its potential to make significant impact
in many area, such as next generation displays, ultraviolet (UV) detectors, solar cells, charge-coupled devices (CCDs), and
so on. Central to the realization of transparent electronics is the development of high performance fully transparent thin-film
transistors (TFTs). One-dimensional (1-D) nanostructures have been the focus of current researches due to their unique physical
properties and potential applications in nanoscale electronics and optoelectronics. Among 1-D nanostructures, transparent
metal oxide nanowires are one of the best candidates to make fully transparent TFTs. We provide in this paper the most recent
development on the fabrication of fully transparent TFT using metal oxide nanowires as the device elements. First, the review
article gives a general introduction about the development of transparent electronics using different kinds of materials as
the devices elements, including organic semiconductors, metal oxide thin films, and metal oxide nanowires. Second, the growth
of metal oxide nanowires using vapor phase methods governed by two different growth mechanisms: vaporsolid mechanism and vapor-liquid-solid
mechanism, respectively, are described. Third, the fabrication of transparent and flexible TFTs using different metal oxides
nanowires is comprehensively described. In conclusion, the challenges and prospects for the future are discussed.
Keywordsthin-film transistor (TFT)-field-effect transistor (FET)-transparent electronics-nanowires-metal oxide
Frontiers of Optoelectronics in China 04/2012; 3(3):217-227.
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WeiHua Li,
Meng Meng,
FangYang He,
YuPing Wan,
HuYin Xue,
Wei Liu,
WeiWei Yin, Jing Xu,
CaiWei Feng,
ShanLiang Wang,
Xiao Lu,
JinTing Liu,
RiMo Xi
[show abstract]
[hide abstract]
ABSTRACT: Based on the preparation of an anti-diethylstilbestrol (DES) monoclonal antibody, a simple and convenient indirect competitive
enzyme-linked immunosorbent assay (ELISA) method for DES detection has been developed. The monoclonal antibody demonstrated
high sensitivity to DES with an IC50 value of 275 pg mL−1 and detection limit (LOD) of 90 pg mL−1. The specificity of the assay was studied by measuring cross-reactivity of the antibody with structurally related compounds
of ethinyl estradiol (<7%), estrone (<0.1%), estriol (<0.1%), and diethylstilbestrol benzoate (<0.1%). Chicken, fish, shrimp,
urine and bile spiked with different concentration of DES were detected by the developed method, and the recovery rates were
greater than 79.5%. Intra- and inter-assay variations were about 6%. This method exhibited high stability with a coefficient
of variation less than 10% in buffer and in real samples. The LODs in fish/shrimp, liver, feed and urine spiked with DES were
600, 600, 4800 and 600 pg mL−1, respectively. These results confirmed that the antibody to DES was successfully produced and could be used to establish
ELISA methods for DES detection in food producing animals.
Keywordsdiethylstilbestrol–ELISA–monoclonal antibody–drug residue
Chinese Science Bulletin 04/2012; 56(8):749-754. · 1.32 Impact Factor
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ABSTRACT: Laparoscopic pancreaticoduodenectomy (LPD) is a challenging operation to general surgeon. Up to date, only about 135 cases
have been reported, 16 cases in China, 119 cases outside China. The reconstruction of alimentary system is a key procedure
to ensure success of the whole surgery. It is worth investigating the methods of reconstruction in LPD. A retrospective study
is made to investigate the methods of reconstruction in LPD. We analyze 13 cases of LPD performed in our center. Child’s or
modified Child’s method was used to make the reconstruction in our practice. We tried three methods to make the anastomosis
of pancreaticojejunostomy, including end-to-end dunking binding pancreaticojejunostomy in two cases, end-to-end dunking pancreaticojejunostomy
using interrupted suture in two cases, and duct-to-jejunal end-to-side embedding pancreaticojejunostomy in nine cases. The
clinical data was collected and analyzed. Three of four patients, who underwent end-to-end pancreaticojejunostomy, had a little
pancreatic leakage, especially in the first case. None of other nine patients, who underwent duct-to-jejunal end-to-side embedding
pancreaticojejunostomy, was detected to have pancreatic leakage, and the operating time of these nine cases was less than
other four cases. Duct-to-jejunal end-to-side embedding pancreaticojejunostomy is a safe and efficient method of reconstruction
in LPD.
Frontiers of Medicine in China 04/2012; 1(4):369-372.
