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1.
World J Clin Cases ; 7(8): 928-939, 2019 Apr 26.
Article in English | MEDLINE | ID: mdl-31119138

ABSTRACT

BACKGROUND: Chronic total occlusion (CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long-term survival. Although the success rate of CTO percutaneous coronary intervention (CTO-PCI) has improved, CTO-PCI remains technically challenging. The Fielder XT guidewire was designed for CTO lesions. To validate whether the use of the guidewire increases the success rate, we compared the results of CTO-PCI with or without the guidewire. We hypothesized that the use of Fielder XT guidewire can increase the success rate of CTO-PCI. AIM: To investigate whether the use of Fielder XT guidewire increases the final procedural success of CTO-PCI via the anterograde approach. METHODS: Between January 2013 and December 2015, a retrospective study was conducted on 1230 consecutive patients with CTO who received PCI via the anterograde approach at the General Hospital of Northern Theater Command. The patients were divided into an XT Group (n = 686) and a no-XT Group (n = 544) depending on whether Fielder XT guidewire was used. Both groups were compared for clinical parameters, lesion-related characteristics, procedural outcomes and in-hospital complications. The data were statistically analyzed using Pearson's χ 2 test for categorical variables, and Students' t test was used to compare the quantitative data. Significant independent factors and a risk ratio with 95% confidence interval (CI) were assessed by multivariate logistic regression analysis. RESULTS: In total, 1230 patients were recruited; 75.4% of the patients were male, and 55.8% of the patients were in the XT group. The overall success rate was 83.9%, with 87.8% in the XT group. Based on multivariate logistic regression analysis, factors positively associated with procedural success were the use of Fielder XT guidewire (P = 0.005, 95%CI: 1.172-2.380) and systolic blood pressure (P = 0.011, 95%CI: 1.003-1.022), while factors negatively associated with procedural success were blunt stump (P = 0.013, 95%CI: 1.341-11.862), male sex (P = 0.016, 95%CI: 0.363-0.902), New York Heart Association (NYHA) class (P = 0.035, 95%CI: 0.553-0.979), contrast amount (P = 0.018, 95%CI: 0.983-0.998) and occlusion time (P = 0.009, 95%CI: 0.994-0.999). No significant differences were found between the XT group and the no-XT group with respect to clinical parameters, lesion-related characteristics, coronary artery rupture [3 (0.4%) vs 8 (1.5%), P = 0.056], in-hospital death [2 (0.3%) vs 6 (1.1%), P = 0.079] or in-hospital target lesion revascularization [3 (0.4%) vs 7 (1.3%), P < 0.099]. However, there were significant differences between the groups with respect to success rate [602 (87.8%) vs 430 (79.0%), P < 0.001], procedure time [(74 ± 23) vs (83 ± 21), P < 0.001], stent length [(32.0 ± 15.8) vs (37.3 ± 17.6), P < 0.001], contrast amount [(148 ± 46) vs (166 ± 43), P < 0.001], post-PCI myocardial infarction [43 (6.3%) vs 59 (10.8%), P = 0.004], major adverse cardiovascular event [44 (6.4%) vs 57 (10.7%), P = 0.007], side branch loss [31 (4.5%) vs 44 (8.1%), P = 0.009], contrast-induced nephropathy [29 (4.2%) vs 40 (7.4%), P = 0.018] and no reflow [8 (1.2%) vs 14 (2.9%), P = 0.034]. CONCLUSION: The use of Fielder XT guidewire shortens the Procedure and increases the success rate of CTO-PCI, and is also associated with reduced complication rates.

2.
Huan Jing Ke Xue ; 39(10): 4497-4504, 2018 Oct 08.
Article in Chinese | MEDLINE | ID: mdl-30229596

ABSTRACT

The nitrogen (N) pollution of water is a common global problem. To understand the key production process of N2 O and identify the dominant N sources, Tuojia River, a typical agricultural watershed in a subtropical area, was investigated. To analyze the characteristics of dual nitrate isotopes (δ15N-NO3-,δ18O-NO3-) in water, and N isotope (δ15Norg) and carbon-nitrogen ratio (C/N) in sediment organic matter from four reaches(S1-S4), the stable isotopes method was used. The results showed that the sources of nitrate varied significantly among river segments and were affected by agricultural production and human habitation on the land surface. The average δ15N-NO3- in reaches S1, S2, S3, and S4 were 1.72‰, 2.62‰, 4.10‰, and -1.28‰, respectively, while the average δ18O-NO3- were 2.60‰,-0.06‰, 0.85‰, and -0.62‰. The N in terrestrial soil made a large contribution to nitrate sources in reach S1, while soil N, ammonium N fertilizer, and manure played a main role in reaches S2 and S3. Most of the nitrate came from ammonium N fertilizer in reach S4. We also found that δ15Norg in sediment organic matter ranged from -0.69‰ to 11.21‰, and C/N was between 7.30 and 12.02. The mean δ15Norg in reaches S1-S4 were 1.91‰, 2.96‰, 4.72‰, and 3.23‰, respectively, and the mean C/N values were 10.62, 8.63, 9.05, and 9.22, respectively. Although there were some differences in δ15Norg among reaches S2-S4, the dominant N source was sewage in those reaches. However, soil organic matter was the main N source in the sediments of reach S1. The mean δ18O-NO3- in reaches S1-S4 were -7.01‰,-0.17‰,-0.28‰, and -0.60‰, respectively, indicating that nitrification was the key N2 O production process in these reaches. The ratios of δ15N-NO3- and δ18O-NO3- were 0.66,-41.01,-30.23, and 9.39 in reaches S1-S4, respectively. Finally, we found that there was a positive correlation between NO3--N and δ15N-NO3-. To summarize, the N transformation and N2 O production could be dominated by the nitrification process in Tuojia River.

3.
Ying Yong Sheng Tai Xue Bao ; 29(5): 1450-1460, 2018 May.
Article in Chinese | MEDLINE | ID: mdl-29797877

ABSTRACT

This study aimed at exploring the key pathway of methane production and clarifying the composition and distribution of carbon (C) isotopes in the Tuojia River waterbody in Hunan Pro-vince. We estimated CH4 concentrations and fluxes of four reaches (S1, S2, S3 and S4) by a two-layer diffusion model and gas chromatography. The spatial and temporal distribution of CH4 flux and its relationship with environmental factors were examined. The key pathway of CH4 production was investigated by stable C isotope method to analyze the distribution characteristics of 13C isotope (δ13C) of water dissolved CH4 and seston/benthic organic matter. There was significant seasonal variability in water pH, with mean value of (7.27±0.03). The concentration of dissolved oxygen (DO) showed strong seasonal and spatial variations, with the range of 0.43-13.99 mg·L-1. The maximum value of DO occurred in S1 and differed significantly in summer and autumin. In addition, DO differed significantly in winter and other seasons in S2, S3 and S4. The concentration of dissolved organic carbon (DOC) showed a gradual increasing trend from source to estuary. The highest concentration of DOC (8.32 mg·L-1) was found in S2, while the lowest was observed in S1 (0.34 mg·L-1). The electrical conductivity (EC) and oxidation-reduction potential (ORP) of water ranged from 17 to 436 µS·cm-1 and from -52.30 to 674.10 mV, respectively, which were significantly different among the four reaches (P<0.05). Water ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3--N) concentrations were in the ranges of 0.30-1.35 (averaged 0.90±0.10) mg·L-1 and 0.82-2.45 (averaged 1.62±0.16) mg·L-1, respectively. The dissolved concentration and diffusion flux of CH4 ranged from 0 to 5.28 µmol·L-1 and from -0.34 to 619.72 µg C·m-2·h-1, respectively, with significant temporal and spatial variations. They showed a similar trend among reaches. Their values were highest in spring, followed by in winter and lowest in summer and autumn. Spatially, the CH4 concentration and flux followed the order of S2>S3>S4>S1. The correlation analysis showed that CH4 flux was positively correlated with NH4+-N and DOC. The pathway of CH4 production of all reaches was dominated by acetic acid fermentation, while there were obvious differences among the four reaches. The contribution of CH4 from acetic acid fermentation was greatest (87%) in S1, followed by S4(81%), S2(78%) and S3(76%). The mean value of the δ13C for dissolved CH4, seston organic matter and benthic organic matter was -41.64‰±1.91‰, -14.07‰±1.06‰ and -26.20‰±1.02‰, respectively. There was a positive correlation between the δ13C of dissolved CH4 and benthic organic matter, whereas the δ13C value of dissolved CH4 was negatively correlated with CH4 flux.


Subject(s)
Carbon Isotopes , Methane , Rivers/chemistry , Carbon , Environmental Monitoring , Nitrogen
4.
Hu Li Za Zhi ; 64(3): 33-42, 2017 Jun.
Article in Chinese | MEDLINE | ID: mdl-28580557

ABSTRACT

BACKGROUND: Postoperative delirium is a significant complication in elderly patients. The occurrence of delirium may increase the related physical and psychological risks, delay the length of hospital stays, and even lead to death. According to the current evidence-based model, the application of interdisciplinary intervention may effectively prevent delirium, shorten the length of hospital stays, and save costs. PURPOSE: To establish a culturally appropriate interdisciplinary intervention model for preventing postoperative delirium in older Chinese patients. METHODS: The authors adapted the original version of the Hospital Elder Life Program (HELP©) from the Hebrew Senior Life Institute for Aging Research of Harvard University by localizing the content using additional medical resources and translating the modified instrument into Chinese. Furthermore, the final version of this interdisciplinary intervention model for postoperative delirium was developed in accordance with the "guideline of delirium: diagnosis, prevention and management produced by the National Institute for Health and Clinical Excellence in 2010" and the "clinical practice guideline for postoperative delirium in older adults" produced by American geriatrics society in 2014. Finally, the translated instrument was revised and improved using discussions, consultations, and pilot study. RESULTS: The abovementioned procedure generated an interdisciplinary intervention model for preventing postoperative delirium that is applicable to the Chinese medical environment. The content addresses personnel structure and assignment of responsibility; details of interdisciplinary intervention protocols and implementation procedures; and required personnel training. CONCLUSIONS: The revised model is expected to decrease the occurrence of post-operative delirium and other complications in elderly patients, to help them maintain and improve their function, to shorten the length of their hospital stays, and to facilitate recovery.


Subject(s)
Delirium/prevention & control , Postoperative Complications/prevention & control , Aged , Humans
5.
World J Gastroenterol ; 22(29): 6629-37, 2016 Aug 07.
Article in English | MEDLINE | ID: mdl-27547006

ABSTRACT

Metastasis-associated in colon cancer-1 (MACC1) is an oncogene that was first identified in colon cancer. The upstream and downstream of MACC1 form a delicate regulatory network that supports its tumorigenic role in cancers. Multiple functions of MACC1 have been discovered in many cancers. In gastric cancer (GC), MACC1 has been shown to be involved in oncogenesis and tumor progression. MACC1 overexpression adversely affects the clinical outcomes of GC patients. Regarding the mechanism of action of MACC1 in GC, studies have shown that it promotes the epithelial-to-mesenchymal transition and accelerates cancer metastasis. MACC1 is involved in many hallmarks of GC in addition to metastasis. MACC1 promotes vasculogenic mimicry (VM) via TWIST1/2, and VM increases the tumor blood supply, which is necessary for tumor progression. MACC1 also facilitates GC lymphangiogenesis by upregulating extracellular secretion of VEGF-C/D, indicating that MACC1 may be an important player in GC lymphatic dissemination. Additionally, MACC1 supports GC growth under metabolic stress by enhancing the Warburg effect. In conclusion, MACC1 participates in multiple biological processes inside and outside of GC cells, making it an important mediator of the tumor microenvironment.


Subject(s)
Stomach Neoplasms/etiology , Transcription Factors/physiology , Epigenesis, Genetic , Epithelial-Mesenchymal Transition , Humans , Lymphangiogenesis , Proto-Oncogene Proteins c-met/physiology , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Trans-Activators , Transcription Factors/blood , Transcription Factors/genetics , Tumor Microenvironment
6.
J Cell Mol Med ; 19(3): 608-19, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25583328

ABSTRACT

Cyclins/retinoblastoma protein (pRb) pathway participates in cardiomyocyte hypertrophy. MicroRNAs (miRNAs), the endogenous small non-coding RNAs, were recognized to play significant roles in cardiac hypertrophy. But, it remains unknown whether cyclin/Rb pathway is modulated by miRNAs during cardiac hypertrophy. This study investigates the potential role of microRNA-16 (miR-16) in modulating cyclin/Rb pathway during cardiomyocyte hypertrophy. An animal model of hypertrophy was established in a rat with abdominal aortic constriction (AAC), and in a mouse with transverse aortic constriction (TAC) and in a mouse with subcutaneous injection of phenylephrine (PE) respectively. In addition, a cell model of hypertrophy was also achieved based on PE-promoted neonatal rat ventricular cardiomyocyte and based on Ang-II-induced neonatal mouse ventricular cardiomyocyte respectively. We demonstrated that miR-16 expression was markedly decreased in hypertrophic myocardium and hypertrophic cardiomyocytes in rats and mice. Overexpression of miR-16 suppressed rat cardiac hypertrophy and hypertrophic phenotype of cultured cardiomyocytes, and inhibition of miR-16 induced a hypertrophic phenotype in cardiomyocytes. Expressions of cyclins D1, D2 and E1, and the phosphorylated pRb were increased in hypertrophic myocardium and hypertrophic cardiomyocytes, but could be reversed by enforced expression of miR-16. Cyclins D1, D2 and E1, not pRb, were further validated to be modulated post-transcriptionally by miR-16. In addition, the signal transducer and activator of transcription-3 and c-Myc were activated during myocardial hypertrophy, and inhibitions of them prevented miR-16 attenuation. Therefore, attenuation of miR-16 provoke cardiomyocyte hypertrophy via derepressing the cyclins D1, D2 and E1, and activating cyclin/Rb pathway, revealing that miR-16 might be a target to manage cardiac hypertrophy.


Subject(s)
Cardiomegaly/genetics , Cyclin D1/metabolism , Cyclin D2/metabolism , Cyclins/metabolism , MicroRNAs/genetics , Animals , Aorta, Abdominal/surgery , Cell Line , Cyclin D1/biosynthesis , Cyclin D2/biosynthesis , Cyclins/biosynthesis , Disease Models, Animal , Enzyme Activation , HEK293 Cells , Humans , Male , Mice , Mice, Inbred C57BL , MicroRNAs/biosynthesis , Myocytes, Cardiac/pathology , Phenylephrine/pharmacology , Phosphorylation , Proto-Oncogene Proteins c-myc , Rats , Rats, Sprague-Dawley , Retinoblastoma Protein/metabolism , STAT3 Transcription Factor/metabolism
7.
Ying Yong Sheng Tai Xue Bao ; 24(3): 732-40, 2013 Mar.
Article in Chinese | MEDLINE | ID: mdl-23755488

ABSTRACT

This paper studied the effects of 30 years (1981-2010) fertilization with chemical N, P, and K, pig manure (PM), and rice straw (RS) on the soil organic carbon (SOC) and its components contents under intensive double rice cropping. The experiment was established on a typic Hapli-Stagnic Anthrosols in Hunan in 1981, and the soil samples were collected in November 2010. In treatment NPK, the contents of SOC, particulate organic C (POC), and KMnO4-oxidizable C (KMnO4-C) were higher than those in treatments NP and NK. The combined application of chemical and organic fertilizers (treatments NK+PM, NP+RS, and NPK+RS) made the contents of SOC, POC, and KMnO4-C have a significant increase, as compared with chemical fertilizations. Treatment NK+PM had the highest contents of SOC (84.71 t C.hm-2), POC (8.94 t C.hm-2), and KMnO4-C (21.09 t C.hm-2) in top soil (0-45 cm), followed by treatment NPK+RS. Treatment NK+PM had the highest C sequestration (485 kg C.hm-2.a-1) , followed by treatment NPK+RS (375 kg C.hm-2.a-1). The C sequestration efficiency (CSE) of SOC in the treatments of chemical fertilizers plus pig manure or rice straw was obviously higher than that in the treatments of chemical fertilizations, and the CSE of the POC in fertilization treatments (ranging from 0.4% and 1.2%) was lower than that of the KMnO4-C (ranging from 3.0% to 8.3%). By using the values of humification constant (h) and the decay constant (k) in Jenkinson' s equation, it was possible to predict the SOC storages in different treatments in the year 2010; and by using Jenkinson' s equation, it was possible to calculate the C input required to maintain the SOC storages in the year 1981 (AE). The increase of the SOC in treatments NK+PM, NP+RS, and NPK+RS was due to the annual C input being higher than the AE. It was considered that in the double rice cropping areas in subtropical region of China, long-term application of chemical fertilizers combined with pig manure or rice straw could promote the organic carbon sequestration in paddy soils.


Subject(s)
Carbon/analysis , Fertilizers , Organic Chemicals/analysis , Oryza/growth & development , Soil/chemistry , Agriculture/methods , Carbon Sequestration , China , Ecosystem , Particle Size , Time Factors
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(7): 1252-5, 2011 Jun.
Article in Chinese | MEDLINE | ID: mdl-21764708

ABSTRACT

OBJECTIVE: To investigate the effect of dexmedetomidine hydrochloride on inflammatory lung injury and phosphorylation of extracellular regulated protein (ERK1/2) in a rat model of ventilator-induced lung injury (VILI). METHODS: Thirty-six adult male SD rats were randomized into 3 groups (n=12) to receive a 4-h standard ventilation (group C, with tidal volume of 8 ml/kg and respiratory rate of 90/min), high-tidal volume ventilation (group H, with tidal volume of 20 ml/kg and respiratory rate of 50 /min), and high-tidal volume ventilation plus 0.5 µg·kg(-1)·h(-1) dexmedetomidine infusion (group D), with the maintenance of a positive end expiratory pressure (PEEP) of 0 cmH(2)O. After mechanical ventilation the rats were sacrificed to collect the lung lavage liquid and lung tissue to examine the pulmonary inflammatory changes and tumor necrosis factor-α (TNF-α) expression as well as the expressions of ERK1/2 and p-ERK1/2. RESULTS: Groups H and D showed obvious lung injury and significant elevations of the total protein, WBC, MPO, TNF-α, and ERK1/2 phosphorylation as compared with those of group C. The rats in group D showed milder lung pathologies with significantly lower levels of phosphorylation of ERK1/2 and TNF-α compared with those in group H. CONCLUSION: Dexmedetomidine can significantly attenuate VILI, decrease the production of the inflammatory molecules, and inhibit the activation of ERK1/2, demonstrating a protective effect against VILI.


Subject(s)
Dexmedetomidine/therapeutic use , Extracellular Signal-Regulated MAP Kinases/metabolism , Ventilator-Induced Lung Injury/drug therapy , Ventilator-Induced Lung Injury/enzymology , Animals , Male , Rats , Rats, Sprague-Dawley , Tumor Necrosis Factor-alpha/metabolism
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(3): 443-7, 2011 Mar.
Article in Chinese | MEDLINE | ID: mdl-21421479

ABSTRACT

OBJECTIVE: To compare the results of echocardiographic evaluation of pressure overload-induced cardiac remodeling in mice using different ultrasound machines. METHODS: Eighteen C57 BL/6 mice were randomly divided into the sham-operated and the transverse aortic constriction (TAC) groups (n=9). Eight weeks after the operation, the cardiac function of TAC group was evaluated using Siemens ultrasonic instrument with 15L8 probe and the differences between the awake and anesthetized states were compared. The heart rate, left ventricular (LV) dimensions, systolic and diastolic functions were measured in both sham-operated and TAC groups using the Siemens ultrasonic instrument and a high-resolution ultrasonic imaging system for small animals (Vevo 770). RESULTS: Compared with the mice in wakefulness, the anesthetized mice showed significantly decreased heart rate and LV fractional shortening (P<0.001) and markedly increased LV end diastolic diameter and LV end systolic diameter (P<0.05). Both machines sensitively detected the cardiac remodeling of TAC mice in comparison with the sham-operated group. Compared with Siemens machine, Vevo 770 provided a higher resolution of 2D and M mode echocardiography with clearer Doppler frequency image of the mitral valve flow for evaluation of the LV diastolic function. CONCLUSION: Both machines are suitable for evaluating cardiac remodeling induced by pressure overload independent of anesthesia, though anesthesia depresses cardiac function. Vevo 770 is optimal to evaluate LV diastolic function in mice.


Subject(s)
Echocardiography/instrumentation , Hypertrophy, Left Ventricular/diagnostic imaging , Ventricular Remodeling/physiology , Animals , Male , Mice , Mice, Inbred C57BL
10.
Biomed Pharmacother ; 65(1): 22-6, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21051183

ABSTRACT

Cholangiocarcinoma (CCA) is a rare but lethal malignancy arising from the biliary tract epithelium. It has a poor prognosis largely due to the difficulties of early diagnosis and the lack of effective therapies. It is thus imperative to develop new and effective treatments for CCA, which depends heavily on the mechanistic understanding of the disease. Previous studies have suggested that somatic mutations in KRAS, BRAF, and PIK3CA genes are frequently found in several types of human cancers including colon, breast, and lung carcinomas as well as CCA. Yet, the frequency and the involvement of these oncogenic mutations in CCA in Chinese population have not been investigated. In this study, we evaluated the hotspot mutations of KRAS, BRAF, and PIK3CA genes in 34 Chinese CCA patients. Sequencing analysis revealed 13 (38.2%) and 11 (32.4%) patients bearing KRAS and PIK3CA mutations, in which two (5.9%) of them harbored both KRAS and PIK3CA mutations. Surprisingly, no BRAF mutation was detected in all 34 CCA samples. Our findings indicate that somatic mutations in KRAS and PIK3CA but not BRAF oncogenes are closely associated with the development of CCA in Chinese population and provide new potential targets for future therapeutic treatments of the disease.


Subject(s)
Asian People/genetics , Bile Duct Neoplasms/genetics , Bile Ducts, Intrahepatic , Cholangiocarcinoma/genetics , Mutation , Phosphatidylinositol 3-Kinases/genetics , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins/genetics , ras Proteins/genetics , Adult , Aged , Class I Phosphatidylinositol 3-Kinases , Female , Humans , Male , Middle Aged , Proto-Oncogene Proteins p21(ras)
11.
Ying Yong Sheng Tai Xue Bao ; 21(6): 1453-60, 2010 Jun.
Article in Chinese | MEDLINE | ID: mdl-20873620

ABSTRACT

In order to quantify the effects of 27 years application of chemical fertilizers, pig manure, and rice straw on the reddish paddy soil quality in double rice cropping region, the indices of soil bulk density, porosity, maximum water holding capacity, normalized mean weight diameter, pH, cation exchange capacity, available nutrients, organic matter, microbial biomass C, enzyme activities, and rice yield were selected as the evaluation indicators, and classified into four functional groups, i. e., resistance to physical degradation, plant nutrients supply and storage, resistance to biochemical degradation, and sustaining of crop productivity. The soil quality index (SQI) was calculated based on the four functional groups. The results showed that the SQI ranged from 0.544 in treatment CK to 0.729 in treatment NPK plus rice straw. Treatments PK, NP, and NK induced soil degradation, compared to treatment NPK. The deficiencies of soil P and K were the main limiting factors for the double rice productivity in reddish paddy soil area. Even though 30 t x hm(-2) x a(-1) of pig manure and 4.2 t x hm(-2) x a(-1) of rice straw were applied, the soil P and K were still not adequate for the requirement of rice growth. There was no obvious effect of long-term application of lime on the reddish paddy soil quality. The combined application of NPK with organic manure was an important and effective measure in improving soil quality in double rice cropping regions of Southern China.


Subject(s)
Carbon/analysis , Fertilizers , Oryza/growth & development , Soil Microbiology , Soil/analysis , Animals , China , Manure , Nitrogen/analysis , Phosphorus/analysis , Potassium/analysis , Swine , Time Factors
12.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(4): 755-9, 2010 Apr.
Article in Chinese | MEDLINE | ID: mdl-20423843

ABSTRACT

OBJECTIVE: To compare the effects of amlodipine, benidipine and nifedipine on myocardial hypertrophy and evaluate the underlying mechanism. METHODS: Myocardial hypertrophy model was created by transverse aortic constriction (TAC) in C57 BL/6 mice, and plasma catecholamine concentrations were measured 7 days after surgery to confirm the sympathetic activation. The 3 drugs were administered in TAC mice for 7 days and cardiac hypertrophy was evaluated according to the heart-to-body weight ratio (HW/BW). Effects of those drugs on the protein synthesis stimulated by phenylephrine in cultured neonatal cardiac myocytes were also examined. RESULTS: HW/BW and plasma concentrations of catecholamine were significantly increased in TAC mice one week after surgery in comparison with to sham-operated mice. One week after TAC, the HW/BW ratio was significantly lower in the amolodipine but not nifedipine-treated group than in the TAC group. Administration of nifedipine via minipump infusion for one week did not decrease HW/BW ratio. Treatment with amlodpine or benidipine, but not nifedipine, decreased the neonatal rat myocyte protein synthesis induced by phenylephrine stimulation. CONCLUSION: Antihypertrophic effect of DHEs on myocardium is dependent on their potential of blocking N-type calcium channel, and the underlying mechanism involves the sympathetic inhibition.


Subject(s)
Calcium Channel Blockers/pharmacology , Calcium Channels, N-Type/drug effects , Cardiomegaly/drug therapy , Dihydropyridines/pharmacology , Amlodipine/pharmacology , Amlodipine/therapeutic use , Animals , Calcium Channel Blockers/therapeutic use , Cardiomegaly/etiology , Dihydropyridines/therapeutic use , Disease Models, Animal , Male , Mice , Mice, Inbred C57BL , Nifedipine/pharmacology , Nifedipine/therapeutic use
13.
Ying Yong Sheng Tai Xue Bao ; 21(11): 2777-84, 2010 Nov.
Article in Chinese | MEDLINE | ID: mdl-21360999

ABSTRACT

A total of 24 paddy soil samples with different productivity were collected from eight main rice production counties in east, central, and northwest Hunan Province, with the parameters of soil physical properties and clay mineral composition, including bulk density, particle density, porosity, field water-holding capacity, water-stable aggregates, mean weight diameter, normalized mean weight diameter, aggregate destruction rate, organic carbon, organic cementing materials, inorganic cementing materials, and clay minerals determined. The results showed that highly productive (>14,000 kg x hm(-2)) paddy soil possessed bulk density below 1.2 g x cm3, soil particle density about 2.0 g x cm3, and 5-0.5 mm water-stable macroaggregates about 20%. Most of the test parameters had no significant differences between highly productive and medium productive (10,000-13,500 kg x hm(-2)) paddy soils, but significant differences between highly productive and lowly productive (<10,000 kg x hm(-2)) paddy soils, suggesting that under good management, medium productive paddy soils could be upgraded to highly productive paddy soils. At present, the physical properties of lowly productive paddy soils were poor, which need to be improved to raise productivity.


Subject(s)
Agriculture/methods , Biomass , Oryza/growth & development , Soil/analysis , Water/analysis , Porosity
14.
Ying Yong Sheng Tai Xue Bao ; 18(7): 1432-40, 2007 Jul.
Article in Chinese | MEDLINE | ID: mdl-17886631

ABSTRACT

By using leakage pond to simulate the double cropping paddy fields in Dongtinghu Lake area, this paper studied the effects of urea (CF) and controlled release nitrogen fertilizer (CRNF) on the dynamics of surface water pH, electrical conductivity (EC), total nitrogen (TN), ammonia nitrogen (NH4(+)-N) and nitrate nitrogen (NO3(-)-N) and the runoff loss of TN in alluvial sandy loamy paddy soil and purple calcareous clayed paddy soil, the two main paddy soils in this area. The results showed that after applying urea, the surface water TN and NH4(+)-N concentrations reached the peak at the 1st and 3rd day, respectively, and decreased rapidly then. Surface water NO3(-)-N concentration was very low, though it showed a little raise at the 3rd to 7th day after applying urea in purple calcareous clayed paddy soil. In early rice field, surface water pH rose gradually within 15 days after applying urea, while in late rice field, it did within 3 days. EC kept consistent with the dynamics of NH4(+)-N. CRNF, especially 70% N CRNF, gave rise to distinctly lower surface water pH, EC, and TN and NH4(+)-N concentrations within 15 days after application, but NO3- concentration rose slightly at late growth stages, compared with urea application. The monitoring of TN runoff loss indicated that during double cropping rice growth season, the loss amount of TN under urea application was 7.70 kg x hm(-2), accounting for 2.57% of applied urea-N. The two runoff events occurred within 20 days after urea application contributed significantly to the TN runoff loss. CRNF application resulted in a significantly lower TN concentration in runoff water from the 1st runoff event occurred within 10 days of its application, and thereafter, the total TN runoff loss for CRNF and 70% N CRNF application was decreased by 24.5% and 27.2%, respectively, compared with urea application.


Subject(s)
Fertilizers , Nitrogen/analysis , Oryza/growth & development , Soil/analysis , Water Movements , Agriculture/methods , China , Fresh Water , Nitrates/analysis , Water Pollutants/analysis
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