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Human activity intensity is mostly used to quantify the degree of human influence on natural systems, with obvious spatial variability. With Lashihai watershed in Yunnan Province as an example, we used SPOT remote sensing images to update land use data, and obtained a comprehensive index of land use intensity after gridding by assigning weights to different land types, which was considered as the basic human activity intensity. The local tourism activities (horseback riding and boating) were also included. The horseback riding and boating were spatially quantified according to the location of horse farms and the abundance of horses and boats which were superimposed with the basic human activity intensity on the spatial scale of 100 m×100 m to obtain a more accurate comprehensive human activity intensity and to analyze the spatial variations. The results showed that the gridding and the kernel density analysis improved the accuracy of spatial analysis and reflected the spatial superposition and diffusion effects. In the comprehensive human activity intensity map of Lashihai watershed, the highest intensity value of water area was at the mouth of the sea, the lowest intensity value was at the center of the sea, and the overall trend of intensity gradually decreased from the surrounding to the middle. The land settlement had the highest intensity, the intensity value of the agricultural land gathering area was at the middle level, and the intensity of human activities in the forestry area of higher altitude was lower. The comprehensive human activity intensity in the water area of the Lashihai watershed varied most obviously, and differed greatly from the basic human activity intensity. Although there were many local characteristic tourism activities in Yunnan-Guizhou Plateau Wetland scenic area, but their land use types did not change. We need to take them into account when quantifying the intensity of human activities.人类活动强度多用于衡量人类对自然生态的影响程度,具有明显的空间差异性。本研究以云南省拉市海流域为例,采用SPOT遥感影像对土地利用数据进行更新,通过对不同土地类型赋权得到格网化的土地利用强度综合指数,并将其作为基础人类活动强度。同时,又纳入了当地的骑马和划船两项主要旅游活动,基于马场位置和马匹数量以及船只数量,采用地理信息系统的核密度分析方法进行空间定量化,并在100 m×100 m空间尺度上与基础人类活动强度进行叠加,得到更为精确的综合人类活动强度,并对其空间差异进行分析。结果表明: 格网化和核密度分析在提高空间分析精度的同时,将空间上的叠加和扩散效应体现出来;在拉市海流域综合人类活动强度图中,水域的入海口处强度值最高,海中心强度值最低,整体强度呈现从四周向中间逐渐减弱的趋势,陆域的居民点为强度最高区域,农业用地聚集区强度值处于中间水平,海拔较高的林区人类活动强度较低;拉市海水域综合人类活动强度值变化最明显,与基础人类活动强度差异较大。云贵高原湿地景区当地特色旅游活动较多,但并未改变其土地利用类型,因而对其进行人类活动强度量化时,需将其另外考虑在内。.

Objectives: Cigarette smoke, a strong risk factor for cardiovascular diseases, upregulates contractile endothelin (ET) receptors in coronary arteries. The present study examined the effects of second hand cigarette smoke exposure on the contractile endothelin receptors and the role of the MEK1/2 pathway in rat coronary arteries. Design: Rats were exposed to secondhand smoke (SHS) for 8 weeks followed by intraperitoneal injection of a MEK1/2 inhibitor, U0126 daily for another 4 weeks. Contractile responses of isolated coronary arteries were recorded by a sensitive wire myograph. The receptor protein expression levels were examined by Western blotting. Results: The results showed that SHS in vivo caused increased expression of ET receptors ETA and ETB, and that the MEK1/2 blocker U0126 significantly reversed SHS exposure-increased ETA-mediated contractile responses and protein levels. Similar alterations were observed in ETB receptors. U0126 showed dose-dependent effects on SHS-induced response on contractile property and protein levels of the ETB receptor. However, only the higher dose U0126 (15 mg/kg) had inhibitory effects on the ETA receptor. Conclusions: Taken together, our data show that SHS increases contractile ET receptors and MEK1/2 pathway inhibitor offsets SHS exposure-induced ETA and ETB receptor upregulation in rat coronary arteries.

Oxidative stress induced by long-term cyclosporine A (CsA) administration is a major cause of chronic nephrotoxicity, which is characterized by tubular atrophy, tubular cell apoptosis, and interstitial fibrosis in the progression of organ transplantation. Although hydrogen-rich water (HRW) has been used to prevent various oxidative stress-related diseases, its underlying mechanisms remain unclear. This study investigated the effects of HRW on CsA-induced nephrotoxicity and its potential mechanisms. After administration of CsA (25 mg/kg/day), rats were treated with or without HRW (12 mL/kg) for 4 weeks. Renal function and vascular activity were investigated. Histological changes in kidney tissues were analyzed using Masson's trichrome and terminal deoxynucleotidyl transferase dUTP nick-end labeling stains. Oxidative stress markers and the activation of the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway were also measured. We found that CsA increased the levels of reactive oxygen species (ROS) and malonaldehyde (MDA), but it reduced glutathione (GSH) and superoxide dismutase (SOD) levels. Such alterations induced vascular dysfunction, tubular atrophy, interstitial fibrosis, and tubular apoptosis. This was evident secondary to an increase in urinary protein, serum creatinine, and blood urea nitrogen, ultimately leading to renal dysfunction. Conversely, HRW decreased levels of ROS and MDA while increasing the activity of GSH and SOD. This was accompanied by an improvement in vascular and renal function. Moreover, HRW significantly decreased the level of Keap1 and increased the expression of Nrf2, NADPH dehydrogenase quinone 1, and heme oxygenase 1. In conclusion, HRW restored the balance of redox status, suppressed oxidative stress damage, and improved kidney function induced by CsA via activation of the Keap1/Nrf2 signaling pathway.

Aim Hydrogen sulphide (H2S) exhibits a dual modulation of isolated artery tension. This study investigated the vasoconstrictive effect of sulphur sodium hydride (NaHS), a donor of gaseous H2S, on rat coronary artery. Methods The contractile response of isolated arteries was recorded using a wire myograph. Fluo-3/AM was used to load vascular smooth muscle, and intracellular calcium was determined using confocal laser microscopy. The protein expression of Rho kinase was examined using Western blot. Results NaHS induced concentration-dependent contractions of rat coronary artery, and the contraction reached approx. 65% of 60 mm KCl-induced contraction. The NaHS-induced contraction was elevated following the removal of endothelium or the use of the nitric oxide synthase inhibitor L-NAME. The cyclooxygenase inhibitor indomethacin reduced NaHS-induced contraction. The Rho kinase inhibitor Y-27632 significantly attenuated NaHS-induced vasoconstriction. Furthermore, NaHS elevated the protein expression of Rho kinase. NaHS-induced contraction was completely abolished in a Ca2+-free solution and suppressed by the Ca2+ influx blocker nifedipine (100 nm). NaHS also significantly increased the change rate of Ca2+ fluorescence intensity. However, treatment with a Cl−/HCO3− exchanger blocker, K+ channel blockers, the mitogen-activated protein kinase inhibitor U-0126 or cyclic adenosine monophosphate did not affect contraction. Species-dependent differences in NaHS-induced vasoconstriction were observed because these effects were only modest in dog coronary artery and absent in rabbit coronary artery. Conclusions NaHS induces the contraction of rat coronary artery, which is dependent on the activation of Ca2+ influx. Rho kinase likely participates in the vasoconstriction.

Vitamin K1 injection induces severe dose-related anaphylactoid reactions and overdose for the treatment of vitamin K deficiency. We aimed to find an optimal and small dose of vitamin K1 injection to treat vitamin K deficiency and avoid anaphylactoid reactions in animal. Rats were administered a vitamin K-deficient diet and gentamicin to establish vitamin K deficiency model. Behaviour tests were performed in beagle dogs to observe anaphylactoid reactions. The results showed an increased protein induced by vitamin K absence or antagonist II (PIVKA-II) levels, a prolonging of prothrombin time (PT) and activated partial thromboplastin time (APTT) and a decrease in vitamin K-dependent coagulation factor (F) II, VII, IX and X activities in the model group. In vitamin K1 0.01 mg/kg group, the liver vitamin K1 levels increased fivefold and the liver vitamin K2 levels increased to the normal amount. Coagulation markers PT, APTT, FVII and FIX activities returned to normal. Both in the 0.1 and 1.0 mg/kg vitamin K1 groups, coagulation functions completely returned to normal. Moreover, the amount of liver vitamin K1 was 40 (0.1 mg/kg) or 100 (1.0 mg/kg) times as in normal. Vitamin K2 was about 4 (0.1 mg/kg) or 5 (1.0 mg/kg) times as the normal amount. There was no obvious anaphylactoid symptom in dogs with the dose of 0.03 mg/kg, which is equivalent to the dose of 0.01 mg/kg in rats. These results demonstrated that a small dose of vitamin K1 is effective to improve vitamin K deficiency and to prevent anaphylactoid reactions, simultaneously.

Cyclosporine A (CsA) induces hypertension after transplantation. Hydrogen sulfide (H

Aim Bitter taste is sensed by the bitter taste receptor (TAS2R), which is mainly expressed in the tongue as well as in extra-oral organs, such as the gastrointestinal tract, respiratory tract, brain, heart and testis. This study aimed to investigate whether TAS2R is expressed in the mesenteric, cerebral and omental arteries. Main methods The expression levels of TAS2R mRNA and protein were determined by reverse-transcription polymerase chain reaction and Western blotting, respectively. The location of TAS2R was determined by immunofluorescence imaging. TAS2R agonists were used in a sensitive myograph to study the function of TAS2R in arteries. Key findings The mRNA of rat TAS2Rs, including rTAS2R39, rTAS2R40, rTAS2R108, rTAS2R114, rTAS2R130, rTAS2R137, and rTAS2R140, was expressed in rat mesenteric and cerebral arteries, but rTAS2R114 was not expressed in the cerebral arteries. The mRNA of human TAS2Rs, including hTAS2R3, hTAS2R4, hTAS2R7, hTAS2R10, hTAS2R14, hTAS2R39 and hTAS2R40, was expressed in human omental arteries. The TAS2R7 protein was expressed in rat mesenteric and cerebral arteries, as well as in human omental arteries. Immunofluorescence imaging confirmed that TAS2R7 was located in vascular smooth muscle cells and endothelial cells. The TAS2R agonists, chloroquine and quinine relaxed rat mesenteric arteries and cerebral arteries and human omental arteries in a concentration-dependent manner. Significance TAS2R is expressed in the arteries of systemic circulation, including rat mesenteric and cerebral arteries and human omental arteries. This study provides evidence that TAS2R do exist in the arteries and may be involved in the mediation of vessel functions.

Hydrogen sulfide (H2S), traditionally known for its toxic effects, is now involved in regulating vascular tone. Here we investigated the vasoconstrictive effect of H2S on cerebral artery and the underlying mechanism. Sodium hydrosulfide (NaHS), a donor of H2S, concentration-dependently induced vasoconstriction on basilar artery, which was enhanced in the presence of isoprenaline, a β-adrenoceptor agonist or forskolin, an adenylyl cyclase activator. Administration of NaHS attenuated the vasorelaxant effects of isoprenaline or forskolin. Meanwhile, the NaHS-induced vasoconstriction was diminished in the presence of 8B-cAMP, an analog of cAMP, but was not affected by Bay K-8644, a selective L-type Ca(2+) channel agonist. These results could be explained by the revised effects of NaHS on isoprenaline-induced cAMP elevation and forskolin-stimulated adenylyl cyclase activity. Additionally, NaHS-induced vasoconstriction was enhanced by removing the endothelium or in the presence of L-NAME, an inhibitor of nitric oxide synthase. L-NAME only partially attenuated the effect of NaHS which was given together with forskolin on the pre-contracted artery. In conclusion, H2S induces vasoconstriction of cerebral artery via, at least in part, cAMP/adenylyl cyclase pathway.

Cigarette smoking, a major stroke risk factor, upregulates endothelin receptors in cerebral arteries. The present study examined the effects of MEK1/2 pathway inhibition on cigarette smoke exposure-induced ET receptor upregulation. Rats were exposed to the secondhand smoke (SHS) for 8weeks followed by intraperitoneal injection of MEK1/2 inhibitor, U0126 for another 4weeks. The urine cotinine levels were assessed with high-performance liquid chromatography. Contractile responses of isolated cerebral arteries were recorded by a sensitive wire myograph. The mRNA and protein expression levels of receptor and MEK/ERK1/2 pathway molecules were examined by real-time PCR and Western blotting, respectively. Cerebral artery receptor localization was determined with immunohistochemistry. The results showed the urine cotinine levels from SHS exposure group were significantly higher than those from the fresh group. In addition, the MEK1/2 inhibitor, U0126 significantly reduced SHS exposure-increased ETA receptor mRNA and protein levels as well as contractile responses mediated by ETA receptors. The immunoreactivity of increased ETA receptor expression was primarily cytoplasmic in smooth muscle cells. In contrast, ETB receptor was noted in endothelial cells. However, the SHS-induced decrease in endothelium-dependent relaxation was unchanged after U0126 treatment. Furthermore, SHS increased the phosphorylation of MEK1/2 and ERK1/2 protein in cerebral arteries. By using U0126 could inhibit the phosphorylated ERK1/2 protein but not MEK1/2. Taken together, our data show that treatment with MEK1/2 pathway inhibitor offsets SHS exposure-induced ETA receptor upregulation in rat cerebral arteries.

Summary The main vitamin K-deficient model, minidose warfarin, is different from the pathological mechanism of vitamin K deficiency, which is a shortage of vitamin K. The objective of this study was to establish a new method of vitamin K-deficient model combining a vitamin K-deficient diet with the intragastrical administration of gentamicin in rats. The clotting was assayed by an automated coagulation analyser. The plasma PIVKA-II was assayed by ELISA. The vitamin K status was detected by an HPLC-fluorescence system. In the diet- and gentamicin-induced vitamin K-deficient 14-day group, the rats had undetected vitamin K1 and vitamin K2 in the liver and a prolonged APTT. In the 21-day group, there was also a prolonged PT and a decrease of the FIX activities. In the 28-day group, the undetected vitamin K1 and vitamin K2, the prolonged PT and APTT, and the decrease of the FII, FVII, FIX, and FX activities prompted the suggestion that there were serious deficiencies of vitamin K and vitamin K-dependent coagulation in rats. It is suggested that the diet- and gentamicin-induced vitamin K-deficient 14-day or 21-day model can be used for studies related to the status of vitamin K. The vitamin K-deficient 28-day model can be applied to research involving both the status of vitamin K and of vitamin K-dependent coagulation. In conclusion, the combination of a vitamin K-deficient diet with the administration of gentamicin results in a useful model of vitamin K-deficieny.

Objectives Formononetin, a phytoestrogen, can improve arterial endothelial cell function by upregulating endothelial nitric oxide synthase (eNOS). The estrogen receptor plays an important role in the regulation of eNOS. This study investigated the hypothesis that formononetin upregulates eNOS through estrogen receptors and MAPK pathways. Methods The rat superior mesenteric arteries were cultured with formononetin or formononetin plus inhibitors for 24 h. The isometric tension of the arteries was measured using a myograph system. The mRNA and protein expression levels of eNOS were determined by real-time PCR and immunohistochemistry, respectively. Key findings Acetylcholine (ACh) relaxed the mesenteric arteries precontracted with 5-hydroxytryptamine. This relaxation could be enhanced by formononetin. The removal of endothelium or incubation with l-NAME (a NOS inhibitor) completely abolished the formononetin-enhanced relaxation induced by ACh, suggesting that the formononetin-enhanced vasodilatation is dependent on endothelium and NO pathway. The estrogen receptor inhibitor ICI 182780 attenuated the formononetin-enhanced vasodilatation induced by ACh, suggesting that the formononetin-enhanced arterial relaxation is mediated by the estrogen receptor. Formononetin increased the mRNA and protein expression levels of eNOS. ICI 182780, U0126 (an ERK1/2 inhibitor) and SP600125 (a JNK inhibitor) prevented the increases in arterial relaxation and eNOS levels. Conclusions Formononetin upregulates eNOS expression in mesenteric arteries via estrogen receptors, ERK1/2 and JNK pathways.

Aims The aim of the present study was to determine the optimal initial tension for the rat basilar artery when using wire myography. Methods Rat basilar arteries were mounted in myograph baths. A normalization procedure was performed. K+-rich (60 mM) buffer solution-induced tension was measured in different initial tensions. Results The initial tension of the basilar artery increased from 0.47 to 2.68 mN/mm. Contractile tension was also elevated along with the initial tension. When the initial tension reached 1.63 mN/mm, K+-induced contractile tension of basilar artery achieved its maximum. Thereafter, contractile tension declined as initial tension increased. The duration of equilibration time did not affect K+-induced contractile tension. Conclusion The optimal initial tension is 1.63 ± 0.01 mN/mm in rat basilar arteries when using wire myography.

The aim of the present study was to determine the optimal initial tension, i.e. initial stretch for rat coronary artery when using the multi-wire myograph system. We used the normalization procedure to mimic physiological conditions and to stretch the coronary arterial segments to normalized internal circumference (IC1). It is determined the internal circumference when the vessel relaxed under a transmural pressure of 100 mm Hg (IC100), and the IC1 is calculated by multiplying the IC100 by a factor k. The impact of different factor k on the initial stretch and agonist-induced tension of coronary arteries were investigated. The results showed that the maximal agonist-induced tension was achieved at the factor k value of 0.90 and the initial stretch tension was given 1.16±0.04 mN/mm. The most appropriate factor k value was 0.90-0.95 and the most appropriate initial tension was 1.16-1.52 mN/mm. The equilibration time of the coronary artery segments should be at least 1.0 h. In the same optimal initial tension, the agonist-induced tension increased as equilibration time lengthened.

The severe adverse reaction to vitamin K1 injection is always remarkable and is thought to result from anaphylaxis. Paradoxically, however, some patients administered vitamin K1 injection for the first time have adverse reactions. Using beagle dogs, the present study tested the hypothesis that the response to vitamin K1 is an anaphylactoid reaction. The results showed that serious anaphylaxis-like symptoms appeared in beagle dogs after the administration of vitamin K1 injection for the first time. The plasma histamine concentration increased, and blood pressure decreased sharply. After sensitization, dogs were challenged with vitamin K1 injection and displayed the same degree of symptoms as prior to sensitization. However, when the vitamin K1 injection-sensitized dogs were challenged with a vitamin K1-fat emulsion without solubilizers such asTween-80, the abnormal reactions did not occur. Furthermore, there was no significant change in the plasma immunoglobulin E concentration after vitamin K1 challenge. Following treatment with vitamin K1 injection, the release of histamine and β-hexosaminidase by rat basophilic leukemia-2H3 cells as well as the rate of apoptosis increased. The Tween-80 group displayed results similar to those observed following vitamin K1 injection in vivo. However, the dogs in the vitamin K1-fat emulsion group did not display any abnormal behavior or significant change in plasma histamine. Additionally, degranulation and apoptosis did not occur in rat basophilic leukemia-2H3 cells. Our results indicate that the adverse reaction induced by vitamin K1 injection is an anaphylactoid reaction, not anaphylaxis. Vitamin K1 injection induces the release of inflammatory factors via a non-IgE-mediated immune pathway, for which the trigger may be the solubilizer.

A simple HPLC method for the simultaneous determination of phenylglyoxylic acid (PGA), mandelic acid (MA), styrene glycol (SG) and hippuric acid (HA) in cell culture medium was developed. Analysis was performed on a C(18) column with a mobile phase composed of methanol-potassium dihydrogen phosphate (pH 2.5; 10 mM; 10:90, v/v) at 220 nm. The flow-rate of mobile phase was set at 0.5 mL/min. The mean absolute recoveries of PGA, MA, SG and HA were 95.9, 98.4, 98.0 and 97.1%, respectively. The inter-day and intra-day precisions, determined at three concentration levels, were less than 10% of RSD. The limits of quantification for PGA, MA, SG and HA were 13.2, 13.1, 14.5 and 11.2 microM with RSD less than 20%. The limits of detection for PGA, MA, SG and HA were 4.6, 4.6, 5.1 and 3.9 microM, respectively. The method was successfully applied to study the stereoselective metabolism of SG and MA in primary culture of rat hepatocytes. The results show that there is stereoselective metabolism for both of MA and SG in primary culture of rat hepatocytes. The extent of biotransformation from S-MA to PGA is significantly greater than that from the R enantiomer and the main metabolites are PGA and HA for S-SG and R-SG, respectively.

To investigate the roles of adenomatous polyposis coli (APC) protein and glycogen synthase kinase 3beta (GSK3beta) of smoking murine model in the repair of the injured airway epithelial cells (AECs) in different stages, 30 male Kun-Ming mice were randomly divided into two groups, the control group and the smoking group. There were 24 mice in smoking group, and 6 animals were separately killed at the end of the 1st, 4th, 8th and 12th week after smoking. Then the following tests were undertaken: (1) HE staining of lung section to observe the morphological changes of the bronchi in the smoking mice. (2) Immunohistochemical staining of APC protein and GSK3beta in the AECs. (3) Western blot was used to detect the levels of APC protein, GSK3beta and phosphorated GSK3beta (p-GSK3beta) in pulmonary tissue. (4) Observing the localizations of APC protein and GSK3beta in the AECs by immunofluorescence technique. The results showed: (1) AECs showed changes of predominant injury (1-, 4-week), repair (8-week) and reinjury (12-week) along with smoking time prolonged. The experimental results indicated that the model of smoking mice was duplicated successfully. (2) Immunohistochemical results showed that the expression of APC protein in the AECs increased after 1-week smoking (0.458 +/- 0.062 vs 0.399 +/- 0.060, P0.05 vs control), but was significantly decreased at the end of the 4th week (0.339+/- 0.056, P0.01 vs control) and increased at the end of the 8th and 12th week (0.387 +/- 0.041, 0.378 +/- 0.037, P0.05 vs 4-week). The expression of GSK3beta in the AECs of smoking mice obviously decreased (P0.01 or P0.05 vs control). (3) Western blot showed that the expressions of APC protein and GSK3beta in lung tissue were consistent with the results of immunohistochemistry; and the levels of p-GSK3beta in all smoking models were higher than that in control. (4) The results of immunofluorescence showed that APC protein was localized mainly near the regions of epithelial cell membrane at the end of the 1st and 8th week after smoking, which were dissimilar with the localization in control, and this change was not seen in the location of GSK3beta. Taken together, these results demonstrate that the expressions and localizations of APC protein, GSK3beta and the activity of GSK3beta are dynamically changed in the AECs with experimental smoking injury at different phases, suggesting that APC protein and GSK3beta may be involved in the regulation of migration and proliferation of AECs, and play an important role in the process of repair of airway epithelium injury.