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1.
Although of considerable agronomic importance, our understanding of B toxicity mechanism in plants is still not completely understood, and remains an open question. Therefore, we investigated the effect of increasing levels of B (0, 10, 20 and 30 mg kg−1) on the growth, boron (B) concentrations, stomatal resistance, lipid peroxidation (MDA), membrane permeability (MP), lypoxygenase activity (LOX), proline (PRO) and H2O2 accumulation, and the activities of major antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT and ascorbate peroxidase, APX) of grapevine (Vitis vinifera L. cv. Kalecik Karasi) grafted on 5BB rootstock (V. berlandieri × V. riparia) was investigated. Applied toxic levels of B significantly reduced leaf and root growth and increased the B concentration of the leaf, and stem, bark and root of rootstock. In the all B levels leaf tissues of grapevine accumulated more B than that of the other plant parts. In order to restrict excessive uptake of B, stomatal resistance of the leaves increased especially at high B treatments (20 and 30 mg kg−1). The concentrations of H2O2, MDA and membrane permeability were increased as the result of B toxicity while proline and the activity of lypoxygenase were decreased. Compared with control plants, the activities of SOD and CAT were increased by B treatments while the activity of APX was decreased. To our knowledge, this is the first report that B toxicity elevated the antioxidant enzymes to protect the membrane functions from reactive oxygen species (ROS) injury in grapevine and it was hoped that this study would provide a basis for developing strategies for reducing the risks associated with B toxicity. 相似文献
2.
Individual and combined effects of salinity and B toxicity on growth, the major antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; ascorbate peroxidase, APX) activities, ascorbic acid, proline, and H2O2 accumulation, and stomatal resistance (SR), malondialdehyde (MDA), membrane permeability (MP) and the concentrations of sodium (Na), chloride (Cl) and boron (B) of lettuce were investigated. Boron toxicity and salinity reduced growth of lettuce plants. Under B toxicity, B concentration of the plants was increased, but in the presence of NaCl, the concentration of B was significantly reduced. Sodium and Cl concentrations were increased in B + NaCl and NaCl treatments. Membrane damage was more pronounced in NaCl and B + NaCl treatments. Stomatal resistance of the plants was significantly increased by salinity treatments. The accumulation of proline and ascorbic acid was the highest in the B + NaCl treatment. In general, stress conditions significantly increased H2O2 and antioxidant enzyme (SOD, CAT and APX) activities. The present results indicate that stomatal closure is an important response of lettuce against NaCl and B + NaCl stress. Furthermore NaCl and B + NaCl toxicity-induced oxidative stress in lettuce resulting in lipid peroxidation and membrane damage. Increased antioxidant enzyme activities and also accumulation of ascorbic acid and proline are involved in order to overcome B- and NaCl-induced oxidative stress. 相似文献
3.
V. Gunes A. C. Onmaz A. Pavaloiu G. Kaya Karasu R. van den Hoven 《Equine Veterinary Education》2022,34(9):467-472
The aim of our retrospective study was to produce and analyse epidemiological data on gastrointestinal (GI) disorders of Austrian leisure horses. Case records of horses referred to the Equine Clinic of the Veterinary University of Vienna were collected from an electronic hospital information system using its search options. All cases reported to have suffered a GI disorder between March 2003 and February 2015 were selected. In this period of 4314 days, data of 1833 GI cases, mostly accompanied by colic signs, were analysed. The vast majority of our GI cases appeared in the abdominal parts of the GI tract 96% (1760/1833) while just 1.3% (24/1833) could be definitively attributed to oesophageal disorders, whereas in 2.7% (49/1833) of the cases a definitive diagnosis could not be made. The highest prevalence of GI disorders was seen in July and October/November. A breakdown of figures for cases clustered under the colic syndrome showed that colon impactions in left ventral large and/or pelvic flexure (35%) were the major problem followed by gastric disorders (18%), spasmodic colic (9%), enteritis (7%), caecal tympany (6%); caecal impaction (4%), colitis (3%), abnormal anatomical positions of large colon including complete and partial strangulation/volvulus, nephrosplenic entrapment of the left ventral and dorsal colon and right dorsal displacement of the large colon (3%) and small intestinal volvulus (2.7%). In 12% of the cases, the cause of the abdominal discomfort was likely idiopathic paralytic ileus. The searching tool of the electronic patient data also brought up cases with malabsorbtion/IBD syndrome and GI ruptures, both these contributed less than 1% of the referred GI cases. Results suggested that the causes of colic are diverse, but the major reasons for referred cases of colic in the east Austrian horse population are large colon impaction or displacements. Seasonal distribution and specific causes of gastrointestinal disorders should be considered essential components of the initial clinical assessment of horses presenting with colic. 相似文献
4.
One of the problems encountered in the extrusion of plastic profiles is unbalanced flow at the die exit. It causes deformation of the extrudates at ambient and precludes the material transition through remaining stages of production process (calibration, cooling sections etc). In this paper, geometric parameters of a profile extrusion die are optimized using several objective function definitions by Simulated Annealing-Kriging Meta-Algorithm. Objective functions are defined based on the uniformity of velocity distribution at the die exit. For this, Computational Fluid Dynamics (CFD) simulations are performed for N=70 die geometries. Appropriate geometric parameters (t and L) of the die are variables for the optimization problem. 相似文献
5.
The aim of this study was to investigate possible changes in the gas composition and acid-base values of bovine venous blood samples stored at different temperatures (+4, 22 and 37 degrees C) for up to 48 h. Five healthy cattle were used in the study. A total of 15 blood samples collected from the animals were allocated into three groups, which were, respectively, then stored in a refrigerator adjusted to +4 degrees C (Group I, n=5), at a room temperature of about 22 degrees C (Group II, n=5) and in an incubator adjusted to 37 degrees C (Group III; n=5) for up to 48 h. Blood gas and acid-base values were analysed at 0 (baseline), 1, 2, 3, 4, 5, 6, 12, 24, 36 and 48 h of storage. A significant decrease (p<0.001) was found, in the pH of the refrigerated blood after 5 h and its maximum decrease was recorded at 48 h as 0.04 unit. There were also significant alterations (p<0.001) in the blood pH of the samples stored at room temperature and in the incubator after 2 and 3 h, respectively. The maximum mean alteration in pCO(2) value for Group I was -0.72 kPa during the assessment, while for groups II and III, maximum alterations in pCO(2) were detected as +2.68 and +4.16 kPa, respectively. Mean pO(2) values increased significantly (p<0.001) for Group I after 24 h and for Group II after 6 h, while a significant decrease was recorded for Group III after 24 h (p<0.001). Base excess (BE) and bicarbonate (HCO(3)) fractions decreased significantly for all the groups during the study, compared to their baseline values. In conclusion, acid-base values of the samples stored at 22 and +4 degrees C were found to be within normal range and could be used for clinical purposes for up to 12 and 48 h, respectively, although there were small statistically significant alterations. 相似文献
6.
Huseyin Yilmaz Eda Altan Nuri Turan Aydin Gurel Damla Haktanir Kivilcim Sonmez Sezgin Deniz Ahmet Gulcubuk Emre Gur Gunes Sonmez Juergen A. Richt 《Journal of Equine Veterinary Science》2012
There has been an increase in outbreaks of neuropathogenic equine herpesvirus-1 (EHV-1) in the United States and Europe. However, the presence and frequency of neuropathogenic EHV-1 in Turkish horses are not known at present. This study aimed to investigate the frequency of EHV-1 and neuropathogenic strains of EHV-1 in the Marmara Region of Turkey. Samples were analyzed for the presence of EHV-1 and neuropathogenic EHV-1 by real-time PCR TaqMan probe assays. Overall detection rate of EHV-1 was 45.5% (51 of 112). The detection rates were 70.5% (24 of 34) in aborted fetuses, 53.3% (8 of 15) in neonatal deads, 66.6% (4 of 6) in foals, 40% (2 of 5) in dead mares, and 25% (13 of 52) in living mares. Overall detection rate of neuropathogenic EHV-1 was 7.8% (4 of 51), and the real-time PCR results were confirmed by sequencing. Neuropathogenic strains of EHV-1 were detected in the brain and lung of two mares with neurological disease but without a history of abortion, in the brain of a foal that died of respiratory disorder, and in the nasal swab from a mare with a history of abortion. On histopathology, nonpurulent meningoencephalitis, hemorrhages, and vasculitis were seen in the brain. In conclusion, results of this study indicated, for the first time, that the neuropathogenic EHV-1 is circulating in the Marmara Region of Turkey. The results of this study also show that the current risk for non-neuropathogenic strains is high, whereas risk for the neuropathogenic EHV-1-G2254 strain seems to be low. As outbreaks of EHV-1 continue in the Marmara region of Turkey, surveillance for neuropathogenic EHV-1 genotype should be maintained. 相似文献
7.
Use of cardiac troponin kits for the qualitative determination of myocardial cell damage due to traumatic reticuloperitonitis in cattle 总被引：1，自引：0，他引：1
This study was designed to investigate whether kits to measure circulating cardiac troponin-I (cTn-I) and cardiac troponin-T (cTn-T) can be used to determine myocardial cell damage in cattle with traumatic reticuloperitonitis (trp). Twenty cattle with trp were compared with 10 clinically healthy cattle. cTn-I and cTn-T were determined qualitatively and cTn-I was determined quantitatively; biochemical analyses were also performed on both groups. The mean serum concentrations of total protein, globulin, glucose and calcium, and the mean activities of creatine kinase mb, aspartate aminotransferase, lactate dehydrogenase and gamma-glutamyl transferase were higher in the cattle with trp than in the control group. The cTn-I and cTn-T kits both gave positive results in three of the cattle with trp and the quantitative measurement of cTn-I was positive in 11 of the trp cases. Both tests were negative in the healthy cattle. 相似文献
8.
In this study, the effect of combined feeding Black Sea trout (Salmo trutta labrax) broodstock with commercial feed and mealworm larvae (Tenebrio molitor) for 50 days before the breeding period in order to evaluate the gamete quality. While the control group was fed with commercial feed, mealworm larvae were given as an additional protein source 2 days a week and 3 days a week to the experimental groups formed from female and male individuals. In addition to the growth parameters, the number of eggs (number/individual) and the egg diameter (mm), sperm volume (ml), density of spermatozoa (×109 cell/ml), total motility (%), progressive motility (%) and average curvilinear velocity (VCL, µm/sec) values were determined. At the end of the study, the highest live weight gain was found as 46.2 g in the control group of male. The egg diameters were 4.3 ± 1.8 mm and 4.5 ± 1.4 mm in the worm treatment groups fed twice and three times with mealworm respectively. As a result, it was determined that feeding fish with mealworm larvae as an addition to the commercial diet in female individuals did not affect the amount of eggs (p > .05), but the egg diameters were significantly smaller in the control group than the mealworm groups (p < .05). In spermatological characteristics, only the amount of sperm was different between the groups (p < .05); all other parameters were found to be similar to each other with no statistical differences (p > .05). 相似文献
9.
Viktoriya Dzyuba Borys Dzyuba Jacky Cosson Sergii Boryshpolets Gunes Yamaner Vitaliy Kholodniy Marek Rodina 《Fish physiology and biochemistry》2014,40(6):1731-1739
Oxidative stress is a possible source of spermatozoa function deterioration. Seminal fluid (SF) protects spermatozoa against reactive oxygen species (ROS) attack during development in testes and transit through the reproductive tract. Spermatozoa curvilinear velocity and percent of motile cells as well as changes in thiobarbituric acid-reactive substance (TBARS) content, superoxide dismutase, and catalase activity, and uric acid concentration in SF were evaluated in sterlet sperm collected from testes 24 h after hormone induction of spermiation and from Wolffian ducts at 12, 24, 36, and 60 h after hormone injection (HI). While testicular spermatozoa motility was not initiated in activating medium, Wolffian duct sperm showed low motility at 12 h, significant increase at 24 and 36 h, and decrease at 60 h. Testicular SF was characterized by the highest level of TBARS and activity of studied enzymes compared with SF from Wolffian duct sperm at 24 h post-HI. In fluid from Wolffian duct sperm, a significant increase in TBARS content was shown at 36–60 h post-HI. In contrast to testicular SF, in SF from Wolffian duct sperm, this increase was not counterbalanced by changes in the studied variables of antioxidant system. This may be the source of the observed decrease in spermatozoa motility parameters 60 h post-HI. The results may confirm a dual role of ROS in fish sperm physiology. The data with respect to decrease in sturgeon spermatozoa motility parameters at 60 h post-HI should be taken into account in artificial sturgeon propagation. 相似文献
10.
Critical concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), and manganese (Mn) with respect to dry matter yield end antagonistic and synergistic relationships among these nutrients were studied in which tomato (Lycopersicon esculentum L.) was grown in recirculating nutrient solution (NFT). Increments of nutrient elements in the nutrient solution increased the proportional rate of the corresponding nutrient elements. Increasing levels of N negatively correlated with plant P and positively correlated with Ca, Fe, and Zn. Iron and Mn contents of the plants were increased and N, K, Ca, and Mg were decreased as a function of P applied. Increases in K in the nutrient solution caused increases in the concentrations of K, N, P, and Zn, and decreases in the concentration of Ca and Fe. Applied Ca increased the concentrations of Ca and N, and decreased the concentrations of P, Mg, Fe, Zn, and Mn. Potassium, Ca, and Fe contents of the plants were decreased and Zn increased, while N, P, and Mn were not affected by the increasing levels of external Mg. Iron suppressed the plant Mg, Zn, and Mn contents. Synergism between Zn and Fe was seen, while P, K, Ca, Mg, and Mn contents were not affected by Zn levels. Potassium, Ca, Mg, and Fe were not responsive to applied Mn, however, N and P contents of the plants were decreased at the highest levels of Mn. 相似文献