RESUMEN
The study of the variability of physical and chemical factors of soil due to different intensities of livestock grazing can help in the management and maintenance of soil and vegetation. Accordingly, the effect of livestock grazing intensities on soil properties and vegetation in Bozdaghin rangelands of North Khorasan province was investigated. To investigate the effect of different livestock grazing intensities, Three 5-hectare plots in the study area were determined under different treatments (ungrazed (UG), moderate grazing (MG), and heavy grazing (HG)), and the effect of three grazing intensities on vegetation and soil physicochemical and erodibility properties (SPEP) was evaluated. The soil sampling process was performed at depths of 0-15, 15-30 cm and SPEP including soil saturation moisture (SSM), soil texture (percentage of clay, sand, and silt), absorbable potassium (K), electrical conductivity (EC), soil organic matter (SOM), absorbable phosphorus (P), acidity (pH), and bulk density were evaluated, and Soil Erodibility Index (SEI) was calculated by implementing the modified clay ratio relation. To assess the impact of various grazing intensities on all measured characteristics, multivariate analysis of variance (MANOVA) and Duncan tests were utilized to compare the means and their grouping. The results showed that HG compared to MG causes worrying consequences in the first soil depth. Also with increasing grazing intensity, plant production percentage (P < 0.05) and vegetation density (P < 0.01) decreased, and the amount of bare soil (P < 0.01) increased. Also, with increasing grazing intensity, the amount of pH, EC, clay, saturated moisture, and N decreased (P < 0.01), but the amount of silt, sand, K, P, calcium (Ca), lime, and SOM increased (P < 0.01). UG improves soil quality, MG intensity causes optimal conservation and utilization of soil resources, and HG intensity causes severe changes in rangeland soil properties. In areas with MG intensity, due to the increase of the percentage of vegetation (an increase of SOM and prevents the direct impact of raindrops on the soil aggregates) and as a result improvement of soil structure and texture, an increase of water infiltration, and decrease of runoff, and the rate of soil erodibility and water erosion, the rangeland soil decreases and results in sustainable production. This results in optimal conservation and utilization of soil resources. So to sustainably exploit and balance the conservation of biodiversity, livestock production, and soil carbon and nitrogen management, MG is recommended.
Asunto(s)
Monitoreo del Ambiente , Suelo , Carbono/análisis , Irán , Nitrógeno/análisisRESUMEN
Grazing exclosure (GE) is used to improve rangelands in the dry area of the world, so it is important to investigate its effects on soil physicochemical and erodibility properties. This study was conducted to evaluate the effect of long-term GE on the physicochemical and erodibility properties of soil and vegetation as compared with open grazing (OG) areas in Bozdaghi region of North Khorasan province, Iran. Soil and vegetation data were sampled from two sites in the grazing exclosure and the open grazing in early autumn in a randomized complete block design with three replications. Therefore, in each area (GE and OG), three transects of 500-m length and 200-m intervals) were set up. Along each transect, five soil samples were taken at the depths of 0-15 and 15-30 cm in a random-systematic method (15 soil samples in each area) and transferred to the laboratory. In the laboratory, some soil physicochemical properties such as saturation percentage, soil texture (clay, silt, and sand), bulk density, porosity, percentage of soil organic matter (SOM), total nitrogen (TN), exchangeable sodium, potassium, pH, and electrical conductivity (EC) were measured and Soil Erodibility Index (SEI) was calculated by using the modified clay ratio relation. After installing the transects (with a length of 50 m) in three blocks in each area, the parameters of species composition and canopy cover were investigated by the linear-contact method. Data analysis was performed by using an independent t test on Statistical Package for Social Sciences (SPSS) v. 23 software. The results indicate that the application of GE in the Bozdaghi area has a significant positive effect on soil physicochemical properties (P < 0.05). Also, the application of GE has increased the amount of SOM and TN in the surface layer of the soil by about twice as much as the OG pastures. Due to these changes, during 20 years in the GE area, the effects of GE can be positively assessed. According to the obtained results, especially the positive changes in vegetation and the soil physicochemical and erodibility properties, it is recommended to execute the GE plan in the study area.
Asunto(s)
Suelo , Agua , Monitoreo del Ambiente , Irán , NitrógenoRESUMEN
The current study is aimed at investigation of the opium effects on the apoptosis of different cell lines in culture medium and compares such effects with one another. The study is carried out on over 8 cell lines (AA8, AGS, Hela, HepG2, MCF7, N2a, PC12, WEHI). A 2.86 x 10-4 g/ml opium concentration was prepared and added to the culture medium of the cell lines for 48 hours. Cytotoxicity was tested by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. The apoptotic effect of opium on the cell lines was analyzed by Annexin-PI test. Opium with concentration of 2.86 x 10-4 g/ml in 48 hours significantly induces apoptosis in certain cell lines (i.e. AA8, N2a, WEHI), apoptosis and necrosis in some others (i.e. Hela, HepG2, MCF7, and PC12), and also solely necrosis in the AGS cell line. One could infer that the usage of opium with different levels in different tissues leads to certain disorders in some tissues and may have therapeutic effects under distinctive conditions (i.e. unchecked growth of cells) as confirmed by the results.
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Apoptosis/efectos de los fármacos , Opio/toxicidad , Animales , Línea Celular , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , Células PC12 , RatasRESUMEN
Evidence shows that probiotic bacteria can undergo substantial structural and morphological changes in response to environmental stresses, including antibiotics. Therefore, this study investigated the effects of penicillin G (0.015, 0.03, and 0.06 mg/l) on the morphology and adhesion of Lactobacillus acidophilus ATCC 4356, including the colony morphotype, biofilm production, hydrophobicity, H2O2 formation, S-layer structure, and slpA gene expression. Whereas only smooth colonies grew in the presence of penicillin, rough and smooth colony types were observed in the control group. L. acidophilus ATCC 4356 was found to be hydrophobic under normal conditions, yet its hydrophobicity decreased in the presence of the antibiotic. No biofilm was produced by the bacterium, despite testing a variety of different culture conditions; however, treatment with penicillin G (0.015-0.06 mg/l) significantly decreased its production of H2O2 formation and altered the S-layer protein structure and slpA gene expression. The S-protein expression decreased with 0.015 mg/l penicillin G, yet increased with 0.03 and 0.06 mg/l penicillin G. In addition, the slpA gene expression decreased in the presence of 0.015 mg/l of the antibiotic. In conclusion, penicillin G was able to alter the S-layer protein production, slpA gene expression, and certain physicochemical properties of Lactobacillus acidophilus ATCC 4356.
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Antibacterianos/farmacología , Lactobacillus acidophilus/efectos de los fármacos , Lactobacillus acidophilus/crecimiento & desarrollo , Penicilina G/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Interacciones Hidrofóbicas e Hidrofílicas/efectos de los fármacos , Lactobacillus acidophilus/química , Lactobacillus acidophilus/fisiología , Propiedades de Superficie/efectos de los fármacosRESUMEN
Endothelin-1 (ET-1), a circulating vasoactive peptide with potent vasoconstricting and mitogenic properties, may contribute to target-organ damage in hypertension. We investigated whether plasma levels of C-terminal pro-endothelin-1 (CT-pro-ET-1) are associated with left ventricular (LV) mass and aortic root diameter in African-American adults with hypertension. Plasma CT-pro-ET-1 was measured by an immunoluminometric assay in 1041 African Americans (65±9 years, 72% women) with hypertension. LV mass and aortic root diameter were measured according to the American Society of Echocardiography guidelines, and LV mass was indexed by height to the power 2.7 (LVMi). Multivariable regression analyses were used to assess whether plasma CT-pro-ET-1 was associated with LVMi and aortic root diameter, independent of potential confounding variables. Plasma CT-pro-ET-1 was modestly correlated with LVMi (r=0.21, P<0.0001) and aortic root diameter (r=0.09, P=0.004). In separate multivariable regression models that adjusted for age, sex, body mass index, total and high-density lipoprotein cholesterol, smoking history, diabetes, history of myocardial infarction or stroke, and blood pressure-lowering medication and statin use, log CT-pro-ET-1 was significantly associated with greater LVMi (P=0.001) and larger aortic root diameter (P=0.006). CT-pro-ET-1 is independently associated with LVMi and aortic root diameter and may be a marker of target-organ damage in African-Americans adults with hypertension.
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Válvula Aórtica/fisiopatología , Endotelina-1/sangre , Ventrículos Cardíacos/fisiopatología , Hipertensión , Hipertrofia Ventricular Izquierda/sangre , Mediciones Luminiscentes/métodos , Fragmentos de Péptidos/sangre , Negro o Afroamericano , Anciano , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Biomarcadores , Factores de Confusión Epidemiológicos , Ecocardiografía Doppler , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/patología , Humanos , Hipertensión/sangre , Hipertensión/complicaciones , Hipertensión/epidemiología , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/fisiopatología , Masculino , Persona de Mediana Edad , Análisis de Regresión , Factores de Riesgo , Estados Unidos/epidemiologíaRESUMEN
Haemostatic markers have been implicated in the development and progression of vascular disease. We investigated the associations of several haemostatic markers (fibrinogen, D-dimer, FV, FVII, FVIII, von Willebrand factor (vWF) and antithrombin III) with two quantitative measures of vascular disease in adults with hypertension. Participants included 1051 African Americans (65+/-9 years, 72% women) and 894 non-Hispanic whites (61+/-9 years, 55% women) belonging to hypertensive sibships. Phenotypes of vascular disease included the ankle-brachial index (ABI), a measure of peripheral arterial disease, and urinary albumin/creatinine ratio (UACR), a surrogate of glomerular endothelial function. Generalized estimating equations were used to assess whether plasma levels of haemostatic markers were associated with measures of arteriosclerosis, after adjustment for conventional risk factors and medication (statin, aspirin and oestrogen) use. Higher fibrinogen and D-dimer were significantly associated with lower ABI in African Americans (P<0.001 and 0.004 respectively) and in non-Hispanic whites (P<0.001 and 0.010 respectively). Higher fibrinogen (P<0.001), D-dimer (P=0.003), FVIII (P<0.001) and vWF (P<0.001) were significantly associated with higher UACR in African Americans, whereas, in non-Hispanic whites, higher fibrinogen (P=0.020) and FVII (P=0.006) were significantly associated with higher UACR. Our findings indicate that in adults with essential hypertension, several markers in the haemostatic pathway are independently associated with ABI and UACR, two measures of vascular disease..
Asunto(s)
Arteriosclerosis/sangre , Aterosclerosis/sangre , Biomarcadores/sangre , Hipertensión/sangre , Negro o Afroamericano , Anciano , Albuminuria/orina , Índice Tobillo Braquial , Antitrombina III/metabolismo , Arteriosclerosis/diagnóstico , Arteriosclerosis/etnología , Aterosclerosis/diagnóstico , Aterosclerosis/etnología , Creatinina/orina , Factor V/metabolismo , Factor VII/metabolismo , Factor VIII/metabolismo , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Fibrinógeno/metabolismo , Humanos , Hipertensión/diagnóstico , Hipertensión/etnología , Masculino , Persona de Mediana Edad , Población Blanca , Factor de von Willebrand/metabolismoRESUMEN
BACKGROUND: African Americans with hypertension have higher cardiovascular morbidity and mortality than hypertensives from other ethnic groups. Plasma D-dimer, a fragment generated from fibrin during lysis of mature clot in vivo, is a predictor of adverse cardiovascular events. OBJECTIVE: We investigated whether plasma levels of D-dimer differ between African American (AA) and non-Hispanic white (NHW) adults with hypertension. METHODS: Participants included 933 AA (65 +/- 9 years, 72% women) and 821 NHW (61 +/- 9 years, 56% women) from the community. D-dimer was measured using an immunoturbidimetric assay. Multivariable regression analyses, stratified by gender, were performed to assess whether AA ethnicity was associated with D-dimer levels after adjustment for age, body mass index (BMI), total and high-density lipoprotein (HDL) cholesterol, systolic blood pressure, diabetes, history of smoking, medication (statin and aspirin) use, lifestyle variables (physical activity, alcohol intake, and education), estimated glomerular filtration rate (eGFR), and a marker of inflammation, C-reactive protein (CRP). RESULTS: D-dimer levels were higher in AA men and women than in their NHW counterparts (mean +/- SD; men 256 +/- 199 vs. 190 +/- 183 ng mL(-1), P < 0.001; women, 290 +/- 233 vs. 225 +/- 195 ng mL(-1), P < 0.001). In both sexes, after adjustment for age, conventional risk factors, medication use, and lifestyle variables, AA ethnicity remained associated with higher D-dimer levels (P = 0.002 in men, P = 0.006 in women). These associations remained significant after additional adjustment for eGFR and plasma CRP (P = 0.003 in men, P < 0.0001 in women). CONCLUSIONS: Among adults with hypertension, AA ethnicity was independently associated with higher plasma levels of D-dimer.