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1.
J. Rashid D. J. Weiss S. K. Maheswaran M. P. Murtaugh 《Veterinary research communications》1996,20(6):519-531
Local and systemic activation of coagulation is frequently associated with bacterial sepsis. The coagulopathy is due, at least in part, to expression of tissue factor (TF) by monocytes and macrophages. The purpose of this study was to evaluate the expression of procoagulant activity by bovine alveolar macrophages, leukocytes and platelets, and to determine the relative potency of three chemical inhibitors of TF expression (pentoxifylline, retinoic acid, and cyclosporin A). Bovine alveolar macrophages were stimulated with lipopolysaccharide (LPS) derived from Pasteurella haemolytica or recombinant bovine tumour nervous factor (TNF) and dose- and time-dependent effects on TF expression were studied. LPS and TNF induced TF expression in alveolar macrophages and LPS treatment of whole blood induced TF expression in mononuclear cells. Neutrophils and platelets also expressed procoagulant activity, but this activity was not inhibited by anti-bovine TF monoclonal antibody. Pentoxifylline (40 mol/L), retinoic acid (0.01 mmol/L) and cyclosporin A (0.08 mol/L) inhibited TF expression when added concurrently with LPS or TNF, but not when added 4 h after stimulation. TF mRNA was not detected in unstimulated alveolar macrophages by Northern blot analysis. In contrast, exposure to LPS or TNF for 6 h induced marked expression of TF mRNA, which was inhibited by treatment with pentoxifylline, retinoic acid and cyclosporin A. Expression of TNF by alveolar macrophages stimulated with LPS was also inhibited by these compounds. Our results indicate that procoagulant activity expressed by alveolar macrophages and monocytes is associated with expression of TF, whereas procoagulant activity expressed by neutrophils and platelets is not. The concentrations of pentoxifylline and retinoic acid necessary for inhibition of TF expression in vitro may not be achievable in vivo owing to their toxic effects. However, the in vitro concentration of cyclosporin A that inhibited TF expression did not exceed the plasma concentration observed in humans, and therefore may be useful for inhibition of TF expression in vivo.Abbreviations BAL
bronchoalveolar lavage
- LPS
lipopolysaccharide
- cDNA
cloned deoxyribonucleic acid
- cAMP
cyclic adenosine monophosphate
- GAPDH
glyceraldehyde phosphate dehydrogenase
- mRNA
messenger ribonucleic acid
- TF
tissue factor
- TNF
tumour necrosis factor
- DPBS
Dulbecco's phosphate-buffered saline 相似文献
2.
S. Ali M. Ijaz S. H. Farooqi A. Z. Durrani M. I. Rashid A. Ghaffar A. Ali A. Rehman S. Aslam I. Khan A. Masud K. Mehmood 《Equine Veterinary Education》2021,33(2):75-83
Theileria equi (T. equi) is an obligate intra- and extra-erythrocytic parasite that causes equine theileriosis (ET) in equids. Equine theileriosis is considered a notifiable disease of global significance, a major constraint to the international movement of horses, and endemic in many countries. This disease may be difficult to diagnose, as it can produce variable and nonspecific clinical signs. A cross-sectional study was designed for the molecular characterisation of T. equi and to investigate the associated risk factors of ET accompanied by its consequences on haematological and sero-biochemical parameters. A convenience sampling of 500 blood samples were collected from ET suspect horses from January to December 2017. PCR was performed on all blood samples targeting the 18S rRNA gene of T. equi followed by sequencing; 9% animals tested positive with confirmed sequences. The isolates of this study showed high homology with Cuban, Russian and Brazilian isolates of T. equi (accession numbers KY111762.2 , MG551915.1 and KY952237.1 , respectively). Based on multivariate analysis, the principal risk factors consisted of absence of dogs on the premises and presence of tick infestation. The haemato-biochemical parameters showed a decrease in granulocytes and erythrocytes, and an increase in lymphocytes, monocytes, mean corpuscular volume, mean corpuscular haemoglobin, mean platelet volume, glucose, phosphorus and aspartate aminotransferase in positive horses. This is the first study which identified ET in Punjab (Pakistan) using molecular techniques and risk factors together with the haemato-biochemical variations in horses. 相似文献
3.
The application of soil amendments to immobilize heavy metals is a promising technology to meet the requirements for environmentally sound and cost‐effective remediation. The present study was carried out to evaluate the result of phosphogypsum (PG) used alone and in combination with compost (CP) at a mix ratio of 1:1 wet weight ratio (PG + CP) at 10 and 20 g dry weight kg−1 dry soil, on heavy metal immobilization in contaminated soil and on canola growth. The results revealed that the Pb, Cd and Zn uptake of canola plants was reduced by the application of PG alone and when it was mixed with CP as compared with untreated soil. At an application rate of 10 g dry weight kg−1 dry soil of (PG + CP) the dry weight of canola plants increased by 66·8% was increased in comparison with its weight in the untreated soil. The addition of PG alone resulted in more pronounced immobilization of heavy metal as compared with PG mixed with CP. Plant growth was improved with CP addition, but heavy metals immobilization was the greatest in PG alone treatments. Results suggest that PG may be useful for the immobilization of heavy metals in contaminated soils. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
4.
Characterizing Spatial Variability of Soil Textural Fractions and Fractal Parameters Derived from Particle Size Distributions 总被引:1,自引:0,他引:1
Meysam MOHAMMADI Mahmoud SHABANPOUR Mohammad Hossein MOHAMMADI Nasser DAVATGAR 《土壤圈》2019,29(2):224-234
Soil particle size distribution (PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains (D1 and D2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D1 and clay content (R2 = 0.924), a negative correlation between D1 and silt content (R2 = 0.801), and a negative correlation between D2 and sand content (R2 = 0.913). The geometric mean diameter of soil particles had a negative correlation with D1 (R2 = 0.569) and D2 (R2 = 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D1 and D2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D1 and D2 and particle size fractions. According to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture. 相似文献
5.
Abolfazl Faraji Nasser Latifi Amir Hossain Shirani Rad 《Agricultural Water Management》2009,96(1):132-140
The effects of high temperature stress and supplemental irrigation on seed yield and water use efficiency (WUE) of canola (Brassica napus L.) were studied in a field experiment conducted for 2 years. The experiment was a randomized complete block design arranged in split plot, conducted at Agricultural Research Station of Gonbad, Iran. It was arranged in two conditions, i.e. supplemental irrigation and rainfed. Two cultivars of canola (Hyola401 and RGS003) as subplots were grown at five sowing dates as main plots. The sowing dates were 9 November, 6 December, 5 January, 4 February and 6 March in 2005-2006 and 6 November, 6 December, 5 January, 4 February and 6 March in 2006-2007, to have a wide range of environmental conditions around flowering and seed filling periods, and to coincide reproductive stages of the crop with high temperature stress. Seed yield was improved due to field management practices, such as supplemental irrigation and optimum sowing date. Supplemental irrigation was an efficient practice to mitigate water stress, and to increase aboveground dry matter and seed yield. There was a strongly negative relationship between seed yield and air temperature during reproductive stages. Delay in sowing led to more rapid developmental of canola, decreased aboveground dry matter, leaf area index (LAI), harvest index (HI), WUE, and seed yield. Achieving a high aboveground dry matter was an essential prerequisite for high reproductive growth and a high seed yield. Greater seed yield and WUE at first sowing date were associated with greater LAI and aboveground dry matter, and lower temperatures during reproductive stages. The results support the view that WUE can be used as an indirect selection criterion for seed yield in genotypic selection. 相似文献
6.
Dildar Ahmed Parsa Dar Raza Chaudhery Rashid Masih 《International Journal of Fruit Science》2017,17(3):310-322
The present study was conducted to identify natural products in the bioactive fractions of Lagenaria siceraria mesocarp. Column chromatography and gas chromatography-mass spectrometry (GC-MS) was used for separation and identification of phytochemicals. Methanolic extract and its fractions displayed alpha-amylase and xanthine oxidase inhibitory activities comparable to standard drugs. GC-MS analysis of the fractions and column eluates revealed the presence of a variety of chemical compounds, including 4-(methoxymethyl)phenol, 2,2?-methylenebis{6(1,1-dimethylethyl)-4-ethyl}phenol, methyl 2-hydroxy-3-phenylpropanoate, oxacyclododecane-2,8-dione, N-(2-(4-hydroxyphenyl)ethyl] acetamide, 2,3-Epoxycarane, 4-(propan-2-yl)benzaldehyde, octadec-1-ene, 4a-methyl-1-methylidene-1,2,3,4,4a,9,10,10a-octahydrophenanthrene, 2,6-di(propan-2-yl)naphthalene, methyl 3-(4-hydroxy-3,5-dimethylphenyl)propanoate, 4,8a-dimethyl-6-(prop-1-en-2-yl)-3,5,6,7,8,8a-hexahydronaphthalen-2(1H)-one 1,3-dihydro-2-benzofuran, methyl N-hydroxybenzenecarboximidoate, linoleic acid, and palmitic acid. Many of these compounds are being reported for the first time from this plant, the presence of which may explain, at least partly, its medicinal efficacy. The fruit possesses significant anti-enzymatic properties against alpha-amylase and xanthine oxidase, and the most active compounds of mesocarp of the fruit appear in ethyl acetate fraction of its methanolic extract. 相似文献
7.
Jizzakh Province in Uzbekistan is one of the largest irrigated areas in Central Asia without natural drainage.In combination with aridity,climate change and extensive irrigation practices,this has led to the widespread salinization of agricultural land.The aim of this study was to identify opportunities to improve the reclamation status of the irrigated area and how best to effectively use the water resources in Jizzakh Province based on investigations conducted between 1995 and 2016.A database of field measurements of groundwater levels,mineralization and soil salinity conducted by the provincial Hydro-Geological Reclamation Expeditions was used in the study.The total groundwater mineralization was determined using a portable electric conductometer(Progress 1T)and the chloride concentration was determined using the Mohr method.The soil salinity analyses were conducted by applying two different methods:(1)the extraction and assessment of the soluble salt content,and(2)using an SM-138 conductivity sensor applied to a 1:1 mixture of soil sample and water.The analyses of the monitoring results and the salt balance in the"irrigation water–soil–drainage water"system clearly demonstrated that the condition of the irrigated land in the province was not significantly improved.Under these conditions,the stability of crop yields is achieved mainly through the use of large volumes of fertilizer.However,excess amounts of mineral fertilizers can also cause the salinization of soils.The average groundwater salinization value in most of the irrigated land(75.3%)fluctuated between 1.1 and 5.0 g/L,while the values were less than 1.0 g/L in 13.1%of the land and in the range of 5.1–10.0 g/L in 10.5%of the land.During the period of 1995–2016 the salinization level of the irrigated land in Jizzakh Province increased slightly and the area could be divided into the following classes:no salinity(17.7%of the total area),low salinity(51.3%),moderate salinity(29.0%),and high salinity(2.0%).Detailed studies of the salt balance in irrigated land,the impact of climate change,increased fertilizer use,and repeated remediation leaching on the groundwater level and mineralization should be conducted in the future,due to the possibility of accelerated salinization,fertility decline,and reduced yields of agricultural crops. 相似文献
8.
Virucidal efficacy of four new disinfectants 总被引:5,自引:0,他引:5
Eleraky NZ Potgieter LN Kennedy MA 《Journal of the American Animal Hospital Association》2002,38(3):231-234
Virucidal efficacy was evaluated for four recently available disinfectants: chlorine dioxide, potassium peroxymonosulfate, a quaternary ammonium compound, and citricidal (grapefruit extract). Sodium hypochlorite (3%) and tap water were used as positive and negative controls respectively. Feline herpesvirus, feline calicivirus, and feline parvovirus were exposed to the manufacturers' recommended dilutions of the evaluated disinfectants. Both chlorine dioxide and potassium peroxymonosulfate completely inactivated the three viruses used in this study. These disinfectants can aid in controlling nosocomial transmission of viruses with less of the deleterious effects of sodium hypochlorite. The quaternary ammonium compound evaluated in this study and citricidal were not effective against feline calicivirus and feline parvovirus. 相似文献
9.
Takiguchi M Murakami M Nakagawa I Rashid MM Tosa N Chikuma S Hashimoto A Uede T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(1):29-36
MRL/lpr mouse is an established animal model which develops autoimmune diseases including glomerulonephritis, sialoadenitis, hepatitis and inflammatory lung disease. Additionally, it has been reported that lpr strains uniquely accumulate CD3+ CD4- CD8- B220+ (double negative, DN) T cells in lymphoid organs leading to lymphadenopathy and splenomegaly. To investigate the role of CD28/CTLA4-B7 pathway in the development of lymphadenopathy and splenomegaly, MRL/lpr mice were treated with soluble form of CTLA4 molecules, CTLA4IgG, which efficiently blocks this pathway. It was demonstrated that (i) the development of DN T cells was independent of the CD28/CTLA4-B7 pathway, (ii) the CD28/CTLA4-B7 pathway was required for the development of lymphadenopathy and splenomegaly, (iii) the CD28/CTLA4-B7 pathway was important for the accumulation of various cell populations in the lymph node and spleen, (iv) composition of the accumulating cell populations was not altered by CTLA4IgG treatment, and (v) activation of conventional T cells and IL-4 production from conventional T cells were the CD28/CTLA4-B7 pathway dependent. Thus, we concluded that the CD28/CTLA4-B7 pathway was required for the development of full-blown lymphadenopathy and splenomegaly in MRL/lpr mice. 相似文献
10.
The Sepsis-Coagulant Axis: A Review 总被引:3,自引:0,他引:3
Douglas J. Weiss Javed Rashid 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(5):317-324
Activation of coagulation is a normal component of the acute inflammatory response. Inflammatory cytokines initiate coagulation events locally at sites of inflammation by converting endothelium from an antithrombotic surface to a prothrombotic surface; by stimulating tissue factor production, which activates both the extrinsic and intrinsic coagulation systems; and by stimulating production of platelet-activating factors. The fibrinolytic system is initially activated but is subsequently inhibited. This results in a marked imbalance in coagulation and fibrinolysis resulting in a net procoagulant state. When thrombin generation and platelet activation exceed the body's capacity to inactivate or remove these factors, disseminated intravascular coagulation (DIC) results. DIC directly contributes to multiple organ failure and death associated with sepsis. Presently available treatments (ie, heparin and aspirin) are relatively ineffective in treating DIC; however, newer, more potent drugs may soon be available for clinical use. 相似文献