Reactive oxygen species (ROS) attack guanine bases in DNA easily and form 8-hydroxydeoxyguanosine (8-OHdG), which can bind to thymidine rather than cytosine, based on which, the level of 8-OHdG is gen- erally rega...Reactive oxygen species (ROS) attack guanine bases in DNA easily and form 8-hydroxydeoxyguanosine (8-OHdG), which can bind to thymidine rather than cytosine, based on which, the level of 8-OHdG is gen- erally regarded as a biomarker of mutagenesis conse- quent to oxidative stress. For example, higher levels of 8-OHdG are noted in Helicobacter pylori-associated chronic atrophic gastritis as well as gastric cancer. However, we have found that exogenous 8-OHdG can paradoxically reduce ROS production, attenuate the nuclear factor-KB signaling pathway, and ameliorate the expression of proinflammatory mediators such as interleukin (IL)-I, IL-6, cyclo-oxygenase-2, and induc- ible nitric oxide synthase in addition to expression of nicotinamide adenine dinucleotide phosphate oxidase (NOX)-I, NOX organizer-1 and NOX activator-1 in vari- ous conditions of inflammation-based gastrointestinal (GI) diseases including gastritis, inflammatory bowel disease, pancreatitis, and even colitis-associated carci- nogenesis. Our recent finding that exogenous 8-OHdG was very effective in either inflammation-based or oxidative-stress-associated diseases of stress-related mucosal damage has inspired the hope that synthetic 8-OHdG can be a potential candidate for the treatment of inflammation-based GI diseases, as well as the pre- vention of inflammation-associated GI cancer. In this editorial review, the novel fact that exogenous 8-OHdG can be a functional molecule regulating oxidative- stress-induced gastritis through either antagonizing Rac-guanosine triphosphate binding or blocking the signals responsible for gastric inflammatory cascade is introduced.展开更多
AIM:To evaluate gastric motility using electrical bioimpedance(EBI) and gastric changes as a result of stress induced by psychological tests.METHODS:A group of 57 healthy women,aged 40-60 years,was recruited,and a cli...AIM:To evaluate gastric motility using electrical bioimpedance(EBI) and gastric changes as a result of stress induced by psychological tests.METHODS:A group of 57 healthy women,aged 40-60 years,was recruited,and a clinical history and physical examination were performed.The women were free from severe anxiety,chronic or acute stress,severe depression,mental diseases and conditions that affect gastric activity.The women were evaluated under fasting conditions,and using a four-electrode configuration,the gastric signals were obtained through a BIOPAC MP-150 system.The volunteers were evaluated using the following paradigm:basal state,recording during the Stroop Test,intermediate resting period,recording during the Raven Test,and a final resting period.We analyzed the relative areas of the frequency spectrum:A1(1-2 cpm),A2(2-4 cpm),A3(4-8 cpm),and A4(8-12 cpm),as well as the median of area A2 + A3.The data were analyzed by an autoregressive method using a Butterworth filter with MatLab and Origin.Analysis of variance(ANOVA) and Friedman ANOVA(for nonparametric variables) were performed;in addition,pairs of groups were compared using the T dependent and Wilcoxon T tests.RESULTS:The results of the main values of area A2 were not significantly different comparing the five steps of the experimental paradigm.Nevertheless,there was a tendency of this A2 region to decrease during the stress tests,with recuperation at the final resting step.When an extended gastric region was considered(1-4 cpm),significant differences with the psychological stress tests were present(F = 3.85,P = 0.005).The A3 region also showed significant changes when the stress psychological tests were administered(F = 7.25,P < 0.001).These differences were influenced by the changes in the adjacent gastric region of A2.The parameter that we proposed in previous studies for the evaluation of gastric motility by electrical bio-impedance(EBI) was the median of the area under the region from 2 to 8 cpm(A2 + A3).The mean values of these frequencies(median of the A2 + A3 area) with the stress test showed significant changes(F = 5.5,P < 0.001).The results of the WilcoxonT test for the A4 area parameter,which is influenced by the breathing response,changed significantly during the Raven stress test(P < 0.05).CONCLUSION:We confirm that the gastric response to acute psychological stress can be evaluated by short-term EBI.展开更多
AIM:To investigate the role of p53 antibodies (p53Abs),metallothioneins (MTs) and oxidative stress markers in the early detection of dysplasia in chronic ulcerative colitis (UC).METHODS:The study included 30 UC patien...AIM:To investigate the role of p53 antibodies (p53Abs),metallothioneins (MTs) and oxidative stress markers in the early detection of dysplasia in chronic ulcerative colitis (UC).METHODS:The study included 30 UC patients,15 without dysplasia (group Ⅱ) and 15 with dysplasia (group Ⅲ),in addition to 15 healthy volunteers (group Ⅰ,control subjects).The enzyme-linked immunosorbent assay technique was used to measure serum p53Abs and MTs,while advanced oxidation protein products (AOPPs),and reduced glutathione (GSH) levels were measured by spectrophotometric method in all subjects.RESULTS:In group Ⅱ and group Ⅲ compared to group Ⅰ,there were significant increases in serum levels of AOPPs (145.94 ± 29.86 μmol/L and 192.21 ± 46.71 μmol/L vs 128.95 ± 3.06 μmol/L,P < 0.002 and P <0.001,respectively),MTs (8.18 ± 0.35 μg/mL and 9.20 ± 0.58 μg/mL vs 6.12 ± 0.25 μg/mL,P < 0.05 and P < 0.05,respectively),and p53Abs (20.19 ± 3.20 U/mL and 34.66 ± 1.34 U/mL vs 9.42 ± 1.64 U/mL,P < 0.001 and P < 0.001,respectively).There were significantly higher levels of AOPPs (P < 0.05) and p53Abs (P < 0.001) in UC patients with dysplasia compared to those without dysplasia,while MTs showed no significant difference between the 2 groups (P > 0.096).In contrast,GSH levels showed a significant decrease in both patients' groups (1.87 ± 0.02 μmol/mL and 1.37 ± 0.09 μmol/mL vs 2.49 ± 0.10 μmol/mL,P < 0.05 and P < 0.05 in groups Ⅱ and Ⅲ,respectively) compared with group Ⅰ,and the levels were significantly lower in group Ⅲ than group Ⅱ (P < 0.05).There was a positive correlation between AOPPs and both MTs (r=0.678,P < 0.001) and p53Abs (r=0.547,P < 0.001),and also between p53Abs and MTs (r=0.739,P < 0.001).There was a negative correlation between AOPPs and GSH (r =-0.385,P < 0.001),and also between GSH and both MTs (r=-0.662,P < 0.001) and p53Abs (r=-0.923,P < 0.001).CONCLUSION:Oxidative stress and oxidative cellular damage play an important role in the pathogenesis of chronic UC and the associated carcinogenetic process.p53Abs levels could help in early detection of dysplasia in these conditions.展开更多
The coil-to-globule transition of thermally sensitive linear poly(N-isopropylacrylamide) (PNIPAM) labeled with dansyl group is induced by 1.54 μm laser pulses (widths10 ns). The dansyl group is used to follow t...The coil-to-globule transition of thermally sensitive linear poly(N-isopropylacrylamide) (PNIPAM) labeled with dansyl group is induced by 1.54 μm laser pulses (widths10 ns). The dansyl group is used to follow the transition kinetics because its fluorescence intensity is very sensitive to its micro-environment. As the molar ratio of NIPAM monomer to dansyl group increases from 110 to 300, the effect of covalently attached dansyl fluorophores on the transition decreases. In agreement with our previous study in which we used 8-anilino- l-naphthalensulfonic acid ammonium salt free in water as a fluorescent probe, the current study reveals that the transition has two distinct stages with two characteristic times, namely, Tfast≈0.1 ms, which can be attributed to the nucleation and formation of some "pearls" (locally contracting segments) on the chain, and tslow≈0.5 ms, which is related to the merging and coarsening of the "pearls".Tfast is independent of the PNIPAM chain length over a wide range (Mw=2.8× 10^6-4.2 × 10^7 g/mol). On the other hand, Tslow only slightly increases with the chain length.展开更多
The relationship between Ca 2+ and ethylene response was investigated through analyzing the effect of Ca 2+ on the response to ethylene in etiolated tomato (Lycopersicon esculentum Mill cv. Lichun) seedling grow...The relationship between Ca 2+ and ethylene response was investigated through analyzing the effect of Ca 2+ on the response to ethylene in etiolated tomato (Lycopersicon esculentum Mill cv. Lichun) seedling grown in darkness. When the etiolated tomato seedlings were treated with different concentrations of Ca 2+, the 'triple response' phenotype, ethylene production, the expression of ethylene receptor gene NEVER-RIPE (NR) and the content of cytosolic CaM were determined. With the concentration of Ca 2+ in the culture medium increasing from 0 mmol/L to 3.8 mmol/L, the 'triple response' phenotype of etiolated tomato seedling was correspondingly strengthened; meanwhile the ethylene production, the amount of NR gene expression and the concentration of CaM increased respectively. However, when the concentration of Ca 2+ was increased from 3.8 mmol/L to 10 mmol/L, the phenotype of 'triple response', ethylene production, NR gene expression, and the CaM content didn't increase further, but decreased consequently. The results indicated that the effect of Ca 2+ on the ethylene triple response in etiolated tomato seedling was relevant to ethylene biosynthesis and ethylene receptor gene expression which were influenced by applied Ca 2+, and these effects might be mediated through the change of CaM concentration in plant cell.展开更多
OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric an...OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric analysis, affinity chromatography for protein purification, SDS-PAGE, Western-blotting and animal experiment were used. RESULTS: HSP70-PC immunization rendered protective effect to both naive tumorl-bearing mice. All of the naive mice obtained complete resistance to Hcaf cell attack; 40% of the tumor-bearing mice survived for over 90 days, whereas the mice of control group died within 2 weeks (P展开更多
In a 10-day aquarium experiment, this investigation examines macrophyte restoration in eutrophic Lake Taihu, the physiological effects of different plant biomass levels and of increasing natural cyanobacterial concent...In a 10-day aquarium experiment, this investigation examines macrophyte restoration in eutrophic Lake Taihu, the physiological effects of different plant biomass levels and of increasing natural cyanobacterial concentrations on a submerged macrophyte, Vallisneria asiatica. Cyanobacterial stress suppressed the superoxide dismutase (SOD) activity of the plant's leaves and induced the catalase (CAT) and peroxidase (POD) activities of its roots. The soluble protein content in V. asiatica decreased with an increase in natural cyanobacterial concentrations, whereas the malonaldehyde (MDA) increased significantly at chlorophyll a (Chl a) concentrations of 222 and 262 μg/L in water. V. asiatica adapted to the stress caused by cyanobacterial concentrations by adjusting its antioxidant defense system to remove the excessive reactive oxygen species when the algal Chl a concentration was 〉109 μg/L. Additionally, high biomass of V. asiatica (2 222 g FW/m^2) can inhibit the reproduction of cyanobacteria more significantly than low biomass (1 111 g FW/m^2). High biomass of V. asiatica increased the oxidative stress in an individual plant when the initial Chl a concentration in the water reached 222 and 262 μg/L, as expressed by the increased MDA in leaves, compared with low biomass of K asiatica. This provides a basis for controlling cyanobacterial concentrations and V. asiatica biomass for the recovery of V. asiatica in eutrophic Lake Taihu.展开更多
This paper presents the effects of the low-dose irradiation on Tilapia Nilotica. In laboratory experiments the Tilapia Nilotica irradiated by integrated flux of fast neutrons 1×10 9 neutrons/m2 and 1 ×10 10...This paper presents the effects of the low-dose irradiation on Tilapia Nilotica. In laboratory experiments the Tilapia Nilotica irradiated by integrated flux of fast neutrons 1×10 9 neutrons/m2 and 1 ×10 10 neutrons/m2 gave a growth rate more than 40% and 32 % compared with those of controls respectively. The yield of the irradiated Tilapia Nilotica growing with non-irradiated carps and silver carps in a mixed feed condition increased by 8. 6%, 157% and 11. 0% more than those of the controls in the pilot test. The survival rate increases by 21. 8%, 149% and 16. 2% for the aboye-mentioned three species. An increased yield of 52 098 kg fish under irradiation with low dose was obtained in 18. 7 hectare water surface. The results of biological experiments show that the main organic coefficients of the Tilapia Nilotica are greater than those of the controls, and this may be related to the increase of the capabilities of metabolism and resistance to diseases.展开更多
AIM: To compare irritable bowel syndrome (IBS) pa- tients with apparently healthy persons and to evaluate body awareness therapy, which is a physiotherapeutic remedy focusing on normalising tensions in the body, for t...AIM: To compare irritable bowel syndrome (IBS) pa- tients with apparently healthy persons and to evaluate body awareness therapy, which is a physiotherapeutic remedy focusing on normalising tensions in the body, for the treatment of IBS with the hypothesis that altered body tension is associated with the syndrome. METHODS: Twenty-one IBS patients received body awareness therapy two hours weekly for 24 wk. At base- line as well as after 12 and 24 wk, they underwent ex- aminations including resource oriented body examination in combination with body awareness scale evaluation and f illed in gastrointestinal and psychological symptom questionnaires. Saliva cortisol was analysed. A group of 21 apparently healthy persons underwent the same ex- aminations once. RESULTS: Compared to the apparently healthy group, IBS patients scored higher at baseline for gastrointestinal and psychological symptoms. They showed more often alterations in normal body tension patterns, as well as deviating cortisol slopes in saliva. After 24 wk of body awareness therapy, their gastrointestinal and psychologi- cal symptoms were reduced overall. Somatic symptoms decreased in parallel with depressive symptoms. Whole body pain score decreased, coping ability as well as bio- chemical stress markers improved. CONCLUSION: IBS patients scored higher for gastroin- testinal and psychological symptoms, and presented with altered biochemical stress markers. Their body tension deviated compared to healthy controls. Furthermore,body awareness therapy gave relief of both somatic com- plaints, psychological symptoms and normalised body tension. These findings indicate that distorted tension constitutes an important part of the symptoms in IBS.展开更多
NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid (...NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid (ABA), methyl jasmonate, mechanical wounding, and Botrytis cinerea infection. Significant induction of ATAF1 was found in an ABA-deficient mutant aba2 subjected to drought or high salinity, revealing an ABA-independent mechanism of expression. Arabidopsis ATAFl-overexpression lines displayed many altered phenotypes, including dwarfism and short primary roots. Furthermore, in vivo experiments indicate that ATAF1 is a bonafide regulator modulating plant responses to many abiotic stresses and necrotrophic-pathogen infection. Overexpression of ATAF1 in Arabidopsis increased plant sensitivity to ABA, salt, and oxidative stresses. Especially, ATAF1 overexpression plants, but not mutant lines, showed remarkably enhanced plant tolerance to drought. Additionally, ATAF1 overexpression enhanced plant susceptibility to the necrotrophic pathogen B. cinerea, but did not alter disease symptoms caused by avirulent or virulent strains of P. syringae pv tomato DC3000. Transgenic plants overexpressing ATAF1 were hypersensitive to oxidative stress, suggesting that reactive oxygen intermediates may be related to ATAFl-mediated signaling in response to both pathogen and abiotic stresses.展开更多
The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological characteristics.They are synthesized by the liver from cholesterol through several ...The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological characteristics.They are synthesized by the liver from cholesterol through several complementary pathways that are controlled by mechanisms involving finetuning by the levels of certain bile acid species.Although their best-known role is their participation in the digestion and absorption of fat,they also play an important role in several other physiological processes.Thus,genetic abnormalities accounting for alterations in their synthesis,biotransformation and/or transport may result in severe alterations,even leading to lethal situations for which the sole therapeutic option may be liver transplantation.Moreover,the increased levels of bile acids reached during cholestatic liver diseases are known to induce oxidative stress and apoptosis,resulting in damage to the liver parenchyma and,eventually,extrahepatic tissues.When this occurs during pregnancy,the outcome of gestation may be challenged.In contrast,the physical-chemical and biological properties of these compounds have been used as the bases for the development of drugs and as pharmaceutical tools for the delivery of active agents.展开更多
Microsomal glutathione transferase (MGST1, EC 2.5.1.18) is a membrane bound glutathione transferase extensively studied for its ability to detoxify reactive intermediates, including metabolic electrophile intermediate...Microsomal glutathione transferase (MGST1, EC 2.5.1.18) is a membrane bound glutathione transferase extensively studied for its ability to detoxify reactive intermediates, including metabolic electrophile intermediates and lipophilic hydroperoxides through its glutathione dependent transferase and peroxidase activities. It is expressed in high amounts in the liver, located both in the endoplasmic reticulum and the inner and outer mitochondrial membranes. This enzyme is activated by oxidative stress. Binding of GSH and modification of cysteine 49 (the oxidative stress sensor) has been shown to increase activation and induce conformational changes in the enzyme. These changes have either been shown to enhance the protective effect ascribed to this enzyme or have been shown to contribute to cell death through mitochondrial permeability transition pore formation. The purpose of this review is to elucidate how one enzyme found in two places in the cell subjected to the same conditions of oxidative stress could both help protect against and contribute to reactive oxygen species-induced liver injury.展开更多
Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism...Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism of proteins, glucose, fat and energy in skeletal muscle and related mechanisms so as to provide theoretical guidance for alleviating heat stress and improving production performance of animal suffering from heat stress.展开更多
The ground-state and lowest excited-state binding energies of a hydrogenic impurity in GaAs parabolic quantum-well wires (Q WWs) subjected to external electric and magnetic fields are investigated using the finite-d...The ground-state and lowest excited-state binding energies of a hydrogenic impurity in GaAs parabolic quantum-well wires (Q WWs) subjected to external electric and magnetic fields are investigated using the finite-difference method within the quasi-one-dimensional effective potential model. We define an effective radius Pen of a cylindrical QWW, which can describe the strength of the lateral confinement. For the ground state, the position of the largest probability density of electron in x-y plane is located at a point, while for the lowest excited state, is located on a circularity whose radius is Pen. The point and circularity are pushed along the left haft of the center axis of the quantum-well wire by the electric field dire ted along the right half. When an impurity is located at the point or within the circularity, the ground-state or lowest excited-state binding energies are the largest; when the impurity is apart from the point or circularity, the ground-state or lowest excited-state binding energies start to decrease.展开更多
Estrogen hormones as a group of endocrine disruptive compounds (EDC) can interfere with endocrine system in humans and animals. The goal of this study was to investigate the elimination rate of Estrone (El), 17β-...Estrogen hormones as a group of endocrine disruptive compounds (EDC) can interfere with endocrine system in humans and animals. The goal of this study was to investigate the elimination rate of Estrone (El), 17β-estradiol (E2) and 17α-ethinyl estradiol (EE2) in Moving Bed Bioreactor (MBBR). These analytes extracted by Dispersive Liquid-Liquid Microextraction (DLLME) technique, followed by derivatization, and detected by GC/MS. Estrogen removal efficiency in MBBR improved at high solid retention times (SRTs), which notion is owing to development ofnitrification. Estrogenspecificremovalratewasbetween 0,22-1.45μg.(gVSS) 1.d -1 for natural and synthetic hormones. The adsorption rate was 0.9%-3.2% 0-1.3%, and 0.7%-5.7% for E1, E2, and EE2, respectively. In addition, the biodegradation rates were more than 95% for these compounds. These results illustrated that in MBBR, the hiodegradation and the adsorption to biomass are considered as two significant routes for elimination of estrogenic compounds. As a whole, the deterioration rate of estrogens enhanced by MBBR compared to other biological wastewater treatment processes such as conventional activated sludge.展开更多
Oxidative stress is a health condition that could potentially harm the patient, and it is defined as the lack of balance between the production of oxygen free radicals, which rises, and antioxidant defenses, which are...Oxidative stress is a health condition that could potentially harm the patient, and it is defined as the lack of balance between the production of oxygen free radicals, which rises, and antioxidant defenses, which are in decrease. Metabolic syndrome implies a variety of risk factors that are based on abdominal obesity and insulin resistance. Moreover, the importance of metabolic syndrome is emphasized due to the fact that it presents an increase in oxidative stress, which is produced by the sum of alterations that each risk factor produces within the metabolic syndrome pathology. Reducing oxidative stress in these patients is currently one of the most interesting challenges of cardiovascular and metabolic therapeutics, because it is a molecular biology alteration that is not generally diagnosed and, therefore, not treated. The increasing incidence of overweight and obesity cause an increase in the incidence of metabolic syndrome, thus turning into a huge problem that keeps growing at alarming proportions. This syndrome's incidence oscillates between 20 and 40%, depending on the gender, age, ethnic group, and diagnostic criteria used for the definition of the disease. Prospective studies show that metabolic syndrome doubles the risk of cardiovascular disease and causes a five-fold increase in the risk of developing type 2 diabetes. With the aim of decreasing the oxidative stress caused by metabolic syndrome, we investigated the effect of antioxidant protection in DNA repair and cell membranes through the use of blueberry extract, which is the fruit with the highest antioxidant capacity, in patients with metabolic syndrome. Thirty patients were studied for a period of 6 months of intervention, and it could be demonstrated that they showed a highly significant decrease in the damage produced to the DNA, which was measured by the urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the damage caused to the vascular endothelium and cell membranes, which was measured through the urinary excretion of F2-isoprostane. Based on our knowledge, this investigation is the first one to show that lyophilized blueberry extract (BlueKing~) as a dietary supplement, with meals, is an additional therapeutic tool of great value for the treatment of oxidative stress through DNA and cell membrane protection in patients with metabolic syndrome.展开更多
基金Supported by A grant from the Ministry of Education and Science Technology,South Korea,No.2010-0002052
文摘Reactive oxygen species (ROS) attack guanine bases in DNA easily and form 8-hydroxydeoxyguanosine (8-OHdG), which can bind to thymidine rather than cytosine, based on which, the level of 8-OHdG is gen- erally regarded as a biomarker of mutagenesis conse- quent to oxidative stress. For example, higher levels of 8-OHdG are noted in Helicobacter pylori-associated chronic atrophic gastritis as well as gastric cancer. However, we have found that exogenous 8-OHdG can paradoxically reduce ROS production, attenuate the nuclear factor-KB signaling pathway, and ameliorate the expression of proinflammatory mediators such as interleukin (IL)-I, IL-6, cyclo-oxygenase-2, and induc- ible nitric oxide synthase in addition to expression of nicotinamide adenine dinucleotide phosphate oxidase (NOX)-I, NOX organizer-1 and NOX activator-1 in vari- ous conditions of inflammation-based gastrointestinal (GI) diseases including gastritis, inflammatory bowel disease, pancreatitis, and even colitis-associated carci- nogenesis. Our recent finding that exogenous 8-OHdG was very effective in either inflammation-based or oxidative-stress-associated diseases of stress-related mucosal damage has inspired the hope that synthetic 8-OHdG can be a potential candidate for the treatment of inflammation-based GI diseases, as well as the pre- vention of inflammation-associated GI cancer. In this editorial review, the novel fact that exogenous 8-OHdG can be a functional molecule regulating oxidative- stress-induced gastritis through either antagonizing Rac-guanosine triphosphate binding or blocking the signals responsible for gastric inflammatory cascade is introduced.
基金Supported by Research and Graduate Department,2008-2010, University of Guanajuato
文摘AIM:To evaluate gastric motility using electrical bioimpedance(EBI) and gastric changes as a result of stress induced by psychological tests.METHODS:A group of 57 healthy women,aged 40-60 years,was recruited,and a clinical history and physical examination were performed.The women were free from severe anxiety,chronic or acute stress,severe depression,mental diseases and conditions that affect gastric activity.The women were evaluated under fasting conditions,and using a four-electrode configuration,the gastric signals were obtained through a BIOPAC MP-150 system.The volunteers were evaluated using the following paradigm:basal state,recording during the Stroop Test,intermediate resting period,recording during the Raven Test,and a final resting period.We analyzed the relative areas of the frequency spectrum:A1(1-2 cpm),A2(2-4 cpm),A3(4-8 cpm),and A4(8-12 cpm),as well as the median of area A2 + A3.The data were analyzed by an autoregressive method using a Butterworth filter with MatLab and Origin.Analysis of variance(ANOVA) and Friedman ANOVA(for nonparametric variables) were performed;in addition,pairs of groups were compared using the T dependent and Wilcoxon T tests.RESULTS:The results of the main values of area A2 were not significantly different comparing the five steps of the experimental paradigm.Nevertheless,there was a tendency of this A2 region to decrease during the stress tests,with recuperation at the final resting step.When an extended gastric region was considered(1-4 cpm),significant differences with the psychological stress tests were present(F = 3.85,P = 0.005).The A3 region also showed significant changes when the stress psychological tests were administered(F = 7.25,P < 0.001).These differences were influenced by the changes in the adjacent gastric region of A2.The parameter that we proposed in previous studies for the evaluation of gastric motility by electrical bio-impedance(EBI) was the median of the area under the region from 2 to 8 cpm(A2 + A3).The mean values of these frequencies(median of the A2 + A3 area) with the stress test showed significant changes(F = 5.5,P < 0.001).The results of the WilcoxonT test for the A4 area parameter,which is influenced by the breathing response,changed significantly during the Raven stress test(P < 0.05).CONCLUSION:We confirm that the gastric response to acute psychological stress can be evaluated by short-term EBI.
文摘AIM:To investigate the role of p53 antibodies (p53Abs),metallothioneins (MTs) and oxidative stress markers in the early detection of dysplasia in chronic ulcerative colitis (UC).METHODS:The study included 30 UC patients,15 without dysplasia (group Ⅱ) and 15 with dysplasia (group Ⅲ),in addition to 15 healthy volunteers (group Ⅰ,control subjects).The enzyme-linked immunosorbent assay technique was used to measure serum p53Abs and MTs,while advanced oxidation protein products (AOPPs),and reduced glutathione (GSH) levels were measured by spectrophotometric method in all subjects.RESULTS:In group Ⅱ and group Ⅲ compared to group Ⅰ,there were significant increases in serum levels of AOPPs (145.94 ± 29.86 μmol/L and 192.21 ± 46.71 μmol/L vs 128.95 ± 3.06 μmol/L,P < 0.002 and P <0.001,respectively),MTs (8.18 ± 0.35 μg/mL and 9.20 ± 0.58 μg/mL vs 6.12 ± 0.25 μg/mL,P < 0.05 and P < 0.05,respectively),and p53Abs (20.19 ± 3.20 U/mL and 34.66 ± 1.34 U/mL vs 9.42 ± 1.64 U/mL,P < 0.001 and P < 0.001,respectively).There were significantly higher levels of AOPPs (P < 0.05) and p53Abs (P < 0.001) in UC patients with dysplasia compared to those without dysplasia,while MTs showed no significant difference between the 2 groups (P > 0.096).In contrast,GSH levels showed a significant decrease in both patients' groups (1.87 ± 0.02 μmol/mL and 1.37 ± 0.09 μmol/mL vs 2.49 ± 0.10 μmol/mL,P < 0.05 and P < 0.05 in groups Ⅱ and Ⅲ,respectively) compared with group Ⅰ,and the levels were significantly lower in group Ⅲ than group Ⅱ (P < 0.05).There was a positive correlation between AOPPs and both MTs (r=0.678,P < 0.001) and p53Abs (r=0.547,P < 0.001),and also between p53Abs and MTs (r=0.739,P < 0.001).There was a negative correlation between AOPPs and GSH (r =-0.385,P < 0.001),and also between GSH and both MTs (r=-0.662,P < 0.001) and p53Abs (r=-0.923,P < 0.001).CONCLUSION:Oxidative stress and oxidative cellular damage play an important role in the pathogenesis of chronic UC and the associated carcinogenetic process.p53Abs levels could help in early detection of dysplasia in these conditions.
文摘The coil-to-globule transition of thermally sensitive linear poly(N-isopropylacrylamide) (PNIPAM) labeled with dansyl group is induced by 1.54 μm laser pulses (widths10 ns). The dansyl group is used to follow the transition kinetics because its fluorescence intensity is very sensitive to its micro-environment. As the molar ratio of NIPAM monomer to dansyl group increases from 110 to 300, the effect of covalently attached dansyl fluorophores on the transition decreases. In agreement with our previous study in which we used 8-anilino- l-naphthalensulfonic acid ammonium salt free in water as a fluorescent probe, the current study reveals that the transition has two distinct stages with two characteristic times, namely, Tfast≈0.1 ms, which can be attributed to the nucleation and formation of some "pearls" (locally contracting segments) on the chain, and tslow≈0.5 ms, which is related to the merging and coarsening of the "pearls".Tfast is independent of the PNIPAM chain length over a wide range (Mw=2.8× 10^6-4.2 × 10^7 g/mol). On the other hand, Tslow only slightly increases with the chain length.
文摘The relationship between Ca 2+ and ethylene response was investigated through analyzing the effect of Ca 2+ on the response to ethylene in etiolated tomato (Lycopersicon esculentum Mill cv. Lichun) seedling grown in darkness. When the etiolated tomato seedlings were treated with different concentrations of Ca 2+, the 'triple response' phenotype, ethylene production, the expression of ethylene receptor gene NEVER-RIPE (NR) and the content of cytosolic CaM were determined. With the concentration of Ca 2+ in the culture medium increasing from 0 mmol/L to 3.8 mmol/L, the 'triple response' phenotype of etiolated tomato seedling was correspondingly strengthened; meanwhile the ethylene production, the amount of NR gene expression and the concentration of CaM increased respectively. However, when the concentration of Ca 2+ was increased from 3.8 mmol/L to 10 mmol/L, the phenotype of 'triple response', ethylene production, NR gene expression, and the CaM content didn't increase further, but decreased consequently. The results indicated that the effect of Ca 2+ on the ethylene triple response in etiolated tomato seedling was relevant to ethylene biosynthesis and ethylene receptor gene expression which were influenced by applied Ca 2+, and these effects might be mediated through the change of CaM concentration in plant cell.
文摘OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric analysis, affinity chromatography for protein purification, SDS-PAGE, Western-blotting and animal experiment were used. RESULTS: HSP70-PC immunization rendered protective effect to both naive tumorl-bearing mice. All of the naive mice obtained complete resistance to Hcaf cell attack; 40% of the tumor-bearing mice survived for over 90 days, whereas the mice of control group died within 2 weeks (P
基金Supported by the Research Institute for East Asia Environments of Kyushu University and Mitsubishi Corporation in Japan
文摘In a 10-day aquarium experiment, this investigation examines macrophyte restoration in eutrophic Lake Taihu, the physiological effects of different plant biomass levels and of increasing natural cyanobacterial concentrations on a submerged macrophyte, Vallisneria asiatica. Cyanobacterial stress suppressed the superoxide dismutase (SOD) activity of the plant's leaves and induced the catalase (CAT) and peroxidase (POD) activities of its roots. The soluble protein content in V. asiatica decreased with an increase in natural cyanobacterial concentrations, whereas the malonaldehyde (MDA) increased significantly at chlorophyll a (Chl a) concentrations of 222 and 262 μg/L in water. V. asiatica adapted to the stress caused by cyanobacterial concentrations by adjusting its antioxidant defense system to remove the excessive reactive oxygen species when the algal Chl a concentration was 〉109 μg/L. Additionally, high biomass of V. asiatica (2 222 g FW/m^2) can inhibit the reproduction of cyanobacteria more significantly than low biomass (1 111 g FW/m^2). High biomass of V. asiatica increased the oxidative stress in an individual plant when the initial Chl a concentration in the water reached 222 and 262 μg/L, as expressed by the increased MDA in leaves, compared with low biomass of K asiatica. This provides a basis for controlling cyanobacterial concentrations and V. asiatica biomass for the recovery of V. asiatica in eutrophic Lake Taihu.
文摘This paper presents the effects of the low-dose irradiation on Tilapia Nilotica. In laboratory experiments the Tilapia Nilotica irradiated by integrated flux of fast neutrons 1×10 9 neutrons/m2 and 1 ×10 10 neutrons/m2 gave a growth rate more than 40% and 32 % compared with those of controls respectively. The yield of the irradiated Tilapia Nilotica growing with non-irradiated carps and silver carps in a mixed feed condition increased by 8. 6%, 157% and 11. 0% more than those of the controls in the pilot test. The survival rate increases by 21. 8%, 149% and 16. 2% for the aboye-mentioned three species. An increased yield of 52 098 kg fish under irradiation with low dose was obtained in 18. 7 hectare water surface. The results of biological experiments show that the main organic coefficients of the Tilapia Nilotica are greater than those of the controls, and this may be related to the increase of the capabilities of metabolism and resistance to diseases.
基金Supported by grants from Vstra Gtalandsregionen (proj No 07), Dagmar (proj No 643-2000-19) and the University of Gothenburg, Sweden
文摘AIM: To compare irritable bowel syndrome (IBS) pa- tients with apparently healthy persons and to evaluate body awareness therapy, which is a physiotherapeutic remedy focusing on normalising tensions in the body, for the treatment of IBS with the hypothesis that altered body tension is associated with the syndrome. METHODS: Twenty-one IBS patients received body awareness therapy two hours weekly for 24 wk. At base- line as well as after 12 and 24 wk, they underwent ex- aminations including resource oriented body examination in combination with body awareness scale evaluation and f illed in gastrointestinal and psychological symptom questionnaires. Saliva cortisol was analysed. A group of 21 apparently healthy persons underwent the same ex- aminations once. RESULTS: Compared to the apparently healthy group, IBS patients scored higher at baseline for gastrointestinal and psychological symptoms. They showed more often alterations in normal body tension patterns, as well as deviating cortisol slopes in saliva. After 24 wk of body awareness therapy, their gastrointestinal and psychologi- cal symptoms were reduced overall. Somatic symptoms decreased in parallel with depressive symptoms. Whole body pain score decreased, coping ability as well as bio- chemical stress markers improved. CONCLUSION: IBS patients scored higher for gastroin- testinal and psychological symptoms, and presented with altered biochemical stress markers. Their body tension deviated compared to healthy controls. Furthermore,body awareness therapy gave relief of both somatic com- plaints, psychological symptoms and normalised body tension. These findings indicate that distorted tension constitutes an important part of the symptoms in IBS.
基金We would like to thank Dr Nam-Hai Chua (Rockefeller Univer- sity) for kindly providing the pBA002Myc vector and the Arabi- dopsis Biological Resource Center (ABRC), Ohio State University for providing ToDNA insertion lines. This work was supported by grants from National Natural Science Foundation of China (No. 30530400/90717006/30670195) to Q Xie and Y Wu, the Chinese Academy of Science (KSCX2-YW-N-010 and CXTD-S2005-2), and the (iuangdong Natural Science Foundation, China (No. 5300648) to Z Deng.
文摘NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid (ABA), methyl jasmonate, mechanical wounding, and Botrytis cinerea infection. Significant induction of ATAF1 was found in an ABA-deficient mutant aba2 subjected to drought or high salinity, revealing an ABA-independent mechanism of expression. Arabidopsis ATAFl-overexpression lines displayed many altered phenotypes, including dwarfism and short primary roots. Furthermore, in vivo experiments indicate that ATAF1 is a bonafide regulator modulating plant responses to many abiotic stresses and necrotrophic-pathogen infection. Overexpression of ATAF1 in Arabidopsis increased plant sensitivity to ABA, salt, and oxidative stresses. Especially, ATAF1 overexpression plants, but not mutant lines, showed remarkably enhanced plant tolerance to drought. Additionally, ATAF1 overexpression enhanced plant susceptibility to the necrotrophic pathogen B. cinerea, but did not alter disease symptoms caused by avirulent or virulent strains of P. syringae pv tomato DC3000. Transgenic plants overexpressing ATAF1 were hypersensitive to oxidative stress, suggesting that reactive oxygen intermediates may be related to ATAFl-mediated signaling in response to both pathogen and abiotic stresses.
基金Supported by The Junta de Castilla y Leon(Grants GR75-2008,SA033A08,SA03508 and SA03608)Ministerio de Cienciae Innovacion(Grants BFU2006-12577,MAT2001-2911,MAT2004-04606 y BFU2007-30688-E/BFI)
文摘The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological characteristics.They are synthesized by the liver from cholesterol through several complementary pathways that are controlled by mechanisms involving finetuning by the levels of certain bile acid species.Although their best-known role is their participation in the digestion and absorption of fat,they also play an important role in several other physiological processes.Thus,genetic abnormalities accounting for alterations in their synthesis,biotransformation and/or transport may result in severe alterations,even leading to lethal situations for which the sole therapeutic option may be liver transplantation.Moreover,the increased levels of bile acids reached during cholestatic liver diseases are known to induce oxidative stress and apoptosis,resulting in damage to the liver parenchyma and,eventually,extrahepatic tissues.When this occurs during pregnancy,the outcome of gestation may be challenged.In contrast,the physical-chemical and biological properties of these compounds have been used as the bases for the development of drugs and as pharmaceutical tools for the delivery of active agents.
文摘Microsomal glutathione transferase (MGST1, EC 2.5.1.18) is a membrane bound glutathione transferase extensively studied for its ability to detoxify reactive intermediates, including metabolic electrophile intermediates and lipophilic hydroperoxides through its glutathione dependent transferase and peroxidase activities. It is expressed in high amounts in the liver, located both in the endoplasmic reticulum and the inner and outer mitochondrial membranes. This enzyme is activated by oxidative stress. Binding of GSH and modification of cysteine 49 (the oxidative stress sensor) has been shown to increase activation and induce conformational changes in the enzyme. These changes have either been shown to enhance the protective effect ascribed to this enzyme or have been shown to contribute to cell death through mitochondrial permeability transition pore formation. The purpose of this review is to elucidate how one enzyme found in two places in the cell subjected to the same conditions of oxidative stress could both help protect against and contribute to reactive oxygen species-induced liver injury.
基金Supported by Key Project of Natural Science Foundation of Hubei Province(2013CFA100)National Natural Science Foundation of China(31472117)
文摘Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism of proteins, glucose, fat and energy in skeletal muscle and related mechanisms so as to provide theoretical guidance for alleviating heat stress and improving production performance of animal suffering from heat stress.
文摘The ground-state and lowest excited-state binding energies of a hydrogenic impurity in GaAs parabolic quantum-well wires (Q WWs) subjected to external electric and magnetic fields are investigated using the finite-difference method within the quasi-one-dimensional effective potential model. We define an effective radius Pen of a cylindrical QWW, which can describe the strength of the lateral confinement. For the ground state, the position of the largest probability density of electron in x-y plane is located at a point, while for the lowest excited state, is located on a circularity whose radius is Pen. The point and circularity are pushed along the left haft of the center axis of the quantum-well wire by the electric field dire ted along the right half. When an impurity is located at the point or within the circularity, the ground-state or lowest excited-state binding energies are the largest; when the impurity is apart from the point or circularity, the ground-state or lowest excited-state binding energies start to decrease.
基金the result of PhD thesis approved in the Isfahan University of Medical Sciences(IUMS)to Vice Chancellery of Research of IUMS for the financial support, Research Project,#394774
文摘Estrogen hormones as a group of endocrine disruptive compounds (EDC) can interfere with endocrine system in humans and animals. The goal of this study was to investigate the elimination rate of Estrone (El), 17β-estradiol (E2) and 17α-ethinyl estradiol (EE2) in Moving Bed Bioreactor (MBBR). These analytes extracted by Dispersive Liquid-Liquid Microextraction (DLLME) technique, followed by derivatization, and detected by GC/MS. Estrogen removal efficiency in MBBR improved at high solid retention times (SRTs), which notion is owing to development ofnitrification. Estrogenspecificremovalratewasbetween 0,22-1.45μg.(gVSS) 1.d -1 for natural and synthetic hormones. The adsorption rate was 0.9%-3.2% 0-1.3%, and 0.7%-5.7% for E1, E2, and EE2, respectively. In addition, the biodegradation rates were more than 95% for these compounds. These results illustrated that in MBBR, the hiodegradation and the adsorption to biomass are considered as two significant routes for elimination of estrogenic compounds. As a whole, the deterioration rate of estrogens enhanced by MBBR compared to other biological wastewater treatment processes such as conventional activated sludge.
文摘Oxidative stress is a health condition that could potentially harm the patient, and it is defined as the lack of balance between the production of oxygen free radicals, which rises, and antioxidant defenses, which are in decrease. Metabolic syndrome implies a variety of risk factors that are based on abdominal obesity and insulin resistance. Moreover, the importance of metabolic syndrome is emphasized due to the fact that it presents an increase in oxidative stress, which is produced by the sum of alterations that each risk factor produces within the metabolic syndrome pathology. Reducing oxidative stress in these patients is currently one of the most interesting challenges of cardiovascular and metabolic therapeutics, because it is a molecular biology alteration that is not generally diagnosed and, therefore, not treated. The increasing incidence of overweight and obesity cause an increase in the incidence of metabolic syndrome, thus turning into a huge problem that keeps growing at alarming proportions. This syndrome's incidence oscillates between 20 and 40%, depending on the gender, age, ethnic group, and diagnostic criteria used for the definition of the disease. Prospective studies show that metabolic syndrome doubles the risk of cardiovascular disease and causes a five-fold increase in the risk of developing type 2 diabetes. With the aim of decreasing the oxidative stress caused by metabolic syndrome, we investigated the effect of antioxidant protection in DNA repair and cell membranes through the use of blueberry extract, which is the fruit with the highest antioxidant capacity, in patients with metabolic syndrome. Thirty patients were studied for a period of 6 months of intervention, and it could be demonstrated that they showed a highly significant decrease in the damage produced to the DNA, which was measured by the urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the damage caused to the vascular endothelium and cell membranes, which was measured through the urinary excretion of F2-isoprostane. Based on our knowledge, this investigation is the first one to show that lyophilized blueberry extract (BlueKing~) as a dietary supplement, with meals, is an additional therapeutic tool of great value for the treatment of oxidative stress through DNA and cell membrane protection in patients with metabolic syndrome.