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21.
Background
The SUV3 (suppressor of Var 3) gene encodes a DNA and RNA helicase, which is localized in the mitochondria. Plant SUV3 has not yet been characterized in detail. However, the Arabidopsis ortholog of SUV3 (AT4G14790) has been shown to be involved in embryo sac development. Previously, we have reported that rice SUV3 functions as DNA and RNA helicase and provides salinity stress tolerance by maintaining photosynthesis and antioxidant machinery. Here, we report further analysis of the transgenic OsSUV3 rice plants under salt stress.Findings
The transgenic OsSUV3 overexpressing rice T1 lines showed significantly higher endogenous content of plant hormones viz., gibberellic acid (GA3), zeatin (Z) and indole-3-acetic acid (IAA) in leaf, stem and root as compared to wild-type (WT), vector control (VC) and antisense (AS) plants under salt (200 mM NaCl) stress condition. A similar trend of endogenous plant hormones profile was also reflected in the T2 generation of OsSUV3 transgenic rice under defined parameters and stress condition.Conclusions
In response to stress, OsSUV3 rice plants maintained plant hormone levels that regulate the expression of several stress-induced genes and reduce adverse effects of salt on plant growth and development and therefore sustains crop productivity. 相似文献22.
Shakeri A Bazzaz MB Khabbazi A Fouladi RF 《Pakistan journal of biological sciences: PJBS》2011,14(16):812-816
This study aimed to evaluate color Doppler sonographic findings in carotid arteries in RA patients under pharmacological treatments and to compare them with normal population. Forty nine patients with late RA and 48 healthy age and sex-matched controls were recruited. The two groups were matched for other known risk factors of atherosclerosis including serum lipid abnormalities, smoking status, diabetes mellitus and hypertension. High resolution B-mode color Doppler ultrasound with a 7 MHZ transducer was used for measuring the Common Carotid Intima-Medial Thickness (CCIMT) in both sides in all subjects. Presence of atherosclerotic plaque was also investigated. The mean left and maximum CCIMT was significantly higher in the case group (0.72 vs. 0.62 mm for the left artery; p < 0.01; 0.72 vs. 0.64 mm for the maximum reading; p = 0.01). No atherosclerotic plaque was found in common carotid arteries. There were 3 (6.1), 7 (14.3) and 9 (18.4%) plaques in left internal carotid artery, right carotid bulb and left carotid bulb in the case group, respectively with no atherosclerotic plaques in the controls (p = 0.24, 0.01 and < 0.001, respectively). Comparing the findings by gender in the case group with the controls, the mentioned significant differences were only between the male patients and the controls. The process of atherosclerosis in RA patients is similar to that in normal population. However, it is apparently accelerated and more advanced in these patients. 相似文献
23.
Background: Neutrophil infiltration plays an important role in inflammatory reactions following spinal cord injury (SCI) and these cells cause substantial secondary tissue damage. The purpose of this study was to determine the effect of oleuropein (OE) on myeloperoxidase (MPO) activity as an index of neutrophil infiltration. Methods: Rats were randomly divided into four groups of 7 rats each as follows: sham-operated group, trauma group, and OE treatment groups (20 mg/kg, i.p., immediately and 1 hour after SCI). Spinal cord samples were taken 24 hours after injury and studied for determination of MPO activity. Results: The results showed that MPO activity was significantly decreased in OE-treated rats. Conclusion: On the basis of our findings, we propose that OE may be effective in protecting rat spinal cord from secondary damage by modulating of neutrophil infiltration.Key Words: Oleuropein (OE), Neutrophil infiltration, Myeloperoxidase 相似文献
24.
Fatemeh Gharishvandi Faranak Kazerouni Esmat Ghanei Ali Rahimipour Malihe Nasiri 《Iranian Biomedical Journal》2015,19(2):76-81
Background:
Hypertension is one the most common causes of chronic kidney disease (CKD). One of the major concerns in hypertensive patients is early detection of renal disorders. In the past, serum creatinine (Scr) concentration was used as a marker of kidney function, but it proffers a late reflection of reduced glomerular filtration rate. Cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) have been recently proven to be useful for quantification of CKD. Therefore, we compared the diagnostic value of NGAL with cystatin C and creatinine to evaluate kidney function in hypertensive patients.Methods:
In this study, 42 hypertensive patients and 30 healthy volunteers were recruited. Serum cystatin C (Scys C) and plasma NGAL were measured using ELISA method. Creatinine, urea, hemoglobin, fibrinogen, and C-reactive protein were measured according to the routine methods. Estimated glomerular filtration rate (eGFR) was considered as the gold standard method (cut-off value of < 78 ml/min/1.73 m2.Results:
In the patient group, plasma NGAL, cystatin C, and creatinine were all significantly correlated with eGFR, and plasma NGAL correlated best with eGFR. Receiver-operating characteristics analysis indicated that plasma NGAL was a better indicator than creatinine and cystatin C for predicting a GFR < 78 ml/min/1.73 m2. The sensitivity and specificity for NGAL were 96% and 100%, for cystatin C were 92% and 60% and for creatinine were 76% and 47%, respectively.Conclusion:
Plasma NGAL demonstrated a higher diagnostic value to detect kidney impairment in the early stages of CKD as compared to Scys C and Scr in hypertensive patients.Key Words: Neutrophil gelatinase-associated lipocalin (NGAL), Cystatin C, Creatinine, Hypertension 相似文献25.
Evaluation of management principles and performance of the System of Rice Intensification (SRI) in Bangladesh 总被引:1,自引:0,他引:1
Experiments were conducted at irrigated and rainfed lowland rice sites in Bangladesh to assess the performance of management practices that have become known as the System of Rice Intensification (SRI). At a research station, SRI management principles such as seedling age, plant spacing, application of organic manure, seedling densities, duration of planting, planting shape and time of planting were evaluated under SRI management as compared to previously established Best Management Practices (BMPs). In on-farm trials, SRI was compared with BMP on 40 farmers’ fields. Nutrient inputs and water management in BMP and SRI treatments were kept at comparable levels. Seedling age, ranging from just sprouted seed to 40-day-old seedlings, had no effect on grain yield in the winter season. In a plant spacing experiment subject to SRI, the highest and lowest grain yields of 7.82 and 5.41 t ha−1 were obtained with spacing of 25 cm × 15 cm (narrow) and 40 cm × 40 cm (wide), respectively. In SRI, seedling density (1–2 seedlings per hill), planting durations (≤15 min to 1–3 h after uprooting) or root placement (L-shape and J-shape) had no effect on grain yield. With regard to time of planting, the highest grain yields were observed with transplanting in the 3rd week of December, with no difference between SRI and BMP management systems. In on-farm trials, BMP gave significantly higher grain yield compared to SRI and farmers’ practice in a triple-cropped area, but grain yields were similar with SRI in a double and single-cropped area when spacing was narrow. The highest profit was obtained with BMP followed by SRI and farmers’ practice in the single-cropping area. Major findings from this study are that under comparable levels of net nutrient input and water management (i) well-implemented BMPs for rice are more efficient for producing high yields than SRI and (ii) there is no intrinsic yield advantage of SRI that could be caused by its individual crop management techniques or some unknown synergism of the different SRI practices proposed. 相似文献
26.
Sodium adsorption ratio (SAR) is one of the water quality indexes that whose is important due to reuse or depletion to environment. Solutes in drain water can be controlled by adsorption, chemical or biological reaction, organic envelope of drainage. Rice husk is the common option of drainage envelops in paddy fields. In this study, the ability of reduction of SAR by rice husk was evaluated in batch scale and physical model of drain envelops. In the batch experiments, the adsorption of SAR parameters was investigated by adding 2 g of rice husk into a 100 ml of sodium chloride solution. The results indicated that rice husk absorbed calcium, magnesium and sodium, respectively. By increasing the temperature, contact time and pH, adsorption of calcium, magnesium and sodium was increased; however, the higher concentration of sodium in soil solution reduced the percentage of adsorption. In a more realistic state, physical models of subsurface drainage in the paddy fields were made. Drainage envelope treatments included of rice husk (H), combination of 20 and 60 % of husk with gravel (H20G80 and H60G40) and a pipe without envelope (NE). Due to higher drain discharge and more sodium removal (lower SAR in drain water), treatment H with the discharge of 16.2 ml/min and SAR of 1.27 (meq/l)0.5 was better in comparison with other treatments. 相似文献
27.
盐胁迫对扁桃砧木叶片SOD、POD和CAT活性的影响 总被引:4,自引:0,他引:4
以温室盆栽的3种扁桃砧木为材料,研究了不同浓度的NaCl、Na2SO4和不同胁迫时间对其叶片活性氧代谢变化的影响.结果表明:NaCl和Na2SO4胁迫下,石头扁桃,桃扁桃和毛桃叶片中POD、CAT活性均随盐浓度的增加而升高,而随着盐胁迫时间的延长其活性有所下降,但都高于对照.SOD活性均随盐浓度的增加先升高后下降,而且后期下降幅度很大.与NaCl胁迫相比,Na2SO4胁迫下这3种砧木叶片中POD、CAT和SOD活性低.从2种盐胁迫下POD、CAT和SOD活性变化规律初步判断这3种砧木的抗盐能力强弱为桃扁桃>毛桃>石头扁桃. 相似文献
28.
Radar soundings of the subsurface of Mars 总被引:2,自引:0,他引:2
Picardi G Plaut JJ Biccari D Bombaci O Calabrese D Cartacci M Cicchetti A Clifford SM Edenhofer P Farrell WM Federico C Frigeri A Gurnett DA Hagfors T Heggy E Herique A Huff RL Ivanov AB Johnson WT Jordan RL Kirchner DL Kofman W Leuschen CJ Nielsen E Orosei R Pettinelli E Phillips RJ Plettemeier D Safaeinili A Seu R Stofan ER Vannaroni G Watters TR Zampolini E 《Science (New York, N.Y.)》2005,310(5756):1925-1928
The martian subsurface has been probed to kilometer depths by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument aboard the Mars Express orbiter. Signals penetrate the polar layered deposits, probably imaging the base of the deposits. Data from the northern lowlands of Chryse Planitia have revealed a shallowly buried quasi-circular structure about 250 kilometers in diameter that is interpreted to be an impact basin. In addition, a planar reflector associated with the basin structure may indicate the presence of a low-loss deposit that is more than 1 kilometer thick. 相似文献
29.
Shah Mujahid Ali Saito Taiju Šindelka Radek Iegorova Viktoriia Rodina Marek Baloch Abdul Rasheed Franěk Roman Tichopád Tomáš Pšenička Martin 《Fisheries Science》2021,87(1):71-83
Fisheries Science - The cleavage pattern of a vertebrate’s embryo is either holoblastic (complete) or meroblastic (partial). Sturgeon and other basal bony fishes represent a transition of the... 相似文献
30.
Ledhyane Ika Harlyan Takashi Fritz Matsuishi Mohammad Faisal Md Saleh 《Fisheries Management and Ecology》2021,28(2):126-137
Malaysian fisheries employ multiple measures to improve management; however, not all are well-suited to the multispecies fisheries. As part of a pilot project, an individual quota system was introduced for the purse-seine fishery off the East Coast of Peninsular Malaysia (ECPM), but no assessment of this particular measure nor the feasibly of its implementation has been confirmed. Therefore, this study analysed spatial and temporal patterns of purse-seine fishing, by collecting catch composition data per landing and its fishing ground within three period fishery surveys between August 2017 and September 2018 at six different landing sites. Similarity and cluster analysis examined species composition and diversity to determine the feasibility of implementing a single-species quota system in this multispecies fishery. Some overlapped of indices results and minor difference in catch composition were found due to changes in spatial and temporal fishing activities. However, no specific spatial or temporal patterns were discernible as structuring the fishing grounds used by purse-seiners. The absence of patterns, using the available data, might be attributable to huge species aggregations and widely distributed and homogenously mixed fish stocks. Thus, it is likely impractical to manage species individually in such a multispecies fishery. 相似文献