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61.
Therapeutic and/or preventive interventions using phytochemical constituents for ischemic heart disease have gained considerable attention worldwide, mainly due to their antioxidant activity. This study investigated the cardioprotective effect and possible mechanism of juglone, a major constituent of the walnut tree, using an isoproterenol (ISO)-induced myocardial infarction (MI) model in rats. Rats were pretreated for five (5) days with juglone (1, 3 mg/kg, i.p) and atenolol (1 mg/kg, i.p) in separate experiments before inducing myocardial injury by administration of ISO (80 mg/kg, s.c) at an interval of 24 h for 2 consecutive days (4th and 5th day). The cardioprotective effect of juglone was confirmed through a lead II electrocardiograph (ECG), cardiac biomarkers (cTnI, CPK, CK-MB, LDH, ALT and AST) and histopathological study. The results of our present study suggest that prior administration of juglone (1 and 3 mg/kg) proved to be effective as a cardioprotective therapeutic agent in reducing the extent of myocardial damage (induced by ISO) by fortifying the myocardial cell membrane, preventing elevated T-waves, deep Q-waves in the ECG, heart to body weight ratio, infarction and also by normalizing cardiac marker enzymes (cTnI, CPK, CK-MB, LDH, ALT and AST) and histopathological changes, such as inflammation, edema and necrosis. In conclusion, this study has identified phytochemical constituents, in particular juglone, as a potential cardioprotective agent.  相似文献   
62.
63.
Field evaluation and risk assessment of transgenic indica basmati rice   总被引:11,自引:1,他引:10  
We report the first field trial of different transgenic lines of Indica Basmati rice (B-370) expressing cry1Ac and cry2A genes. Different transgenic lines were grown under field conditions for two consecutive years, according to RCBD and Split Plot Design respectively. All the biosafety measures were taken into consideration. Sixty neonate larvae of yellow stem borer were artificially infested into each plant in three installments. Data was recorded in terms of dead hearts and white heads at vegetative and flowering stage respectively. Transgenic lines exhibited inherent ability to protect rice plants from target insects (p<0.01). Natural infestations of rice skipper and rice leaf folder were also observed and transgenic plants were statistically superior to their untransformed counterparts. Green house whole plant bioassays were done by infesting two 2nd instar larvae of rice leaf folder per tiller. Transgenics were 96% more resistant than untransformed control plants. The presence of cry genes was observed with Dot blot, PCR and Southern blot analysis, while ELISA and Western blot analysis confirmed the expression of Cry proteins. All lines expressed higher level of Cry proteins when compared with commercially released cultivars of Bt cotton, maize and potato. It was also observed that although toxin titer substantially decreased with increasing age of the plants, it remained well within the limits to kill the target insects. Morphological studies showed significant variation for days to maturity, plant height and panicle length. Cooking qualities of seeds harvested from these lines were compared with the untransformed control. The transgenic lines had no effect on non-target insects (insects belonging to orders other than diptera and lepidoptera) and germination of three local varieties of wheat. Chances of gene spread were calculated at a level of 0.18% cross pollination in experimental lines.  相似文献   
64.
Pesticides are substances that have been widely used throughout the world to kill, repel, or control organisms such as certain forms of plants or animals considered as pests. Depending on their type, dose, and persistence in the environment, they can have impact even on non-target species such as beneficial insects (honeybees) in different ways, including reduction in their survival rate and interference with their reproduction process. Honeybee Apis mellifera is a major pollinator and has substantial economical and ecological values. Colony collapse disorder (CCD) is a mysterious phenomenon in which adult honeybee workers suddenly abandon from their hives, leaving behind food, brood, and queen. It is lately drawing a lot of attention due to pollination crisis as well as global agriculture and medical demands. If the problem of CCD is not resolved soon enough, this could have a major impact on food industry affecting world’s economy a big time. Causes of CCD are not known. In this overview, I discuss CCD, biogenic amines-based-pesticides (neonicotinoids and formamidines), and their disruptive effects on biogenic amine signaling causing olfactory dysfunction in honeybees. According to my hypothesis, chronic exposure of biogenic amines-based-pesticides to honeybee foragers in hives and agricultural fields can disrupt neural cholinergic and octopaminergic signaling. Abnormality in biogenic amines-mediated neuronal signaling impairs their olfactory learning and memory, therefore foragers do not return to their hive – a possible cause of CCD. This overview is an attempt to discuss a hypothetical link among biogenic amines-based pesticides, olfactory learning and memory, and CCD.  相似文献   
65.
The virulence of Isaria fumosorosea alone and integrated with an enhanced formulation of diatomaceous earth (diatomaceous earth + bitterbarkomycin, DEBBM) was tested against the lesser grain borer Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) under laboratory conditions on stored wheat. The fungus was applied to wheat grains at various concentrations of 3.60 × 106, 3.60 × 108, and 3.60 × 1010 conidia/kg alone, or in combination with 15 and 30 ppm of DEBBM. R. dominica was held at 20, 25 and 30°C and two RH regimes (56 and 75%) and mortality was registered after 5, 10 and 15 d. Generally, I. fumosorosea was most effective at 25°C caused the highest mortality of R. dominica at 56% RH. The increase of temperature, concentration and exposure interval increased the insecticidal effect of DEBBM at low RH level. The DE alone suppressed the progeny emergence at higher dose rate as compared I. fumosorosea alone, but their simultaneous use further reduced the progeny production of R. dominica. The integrated use of both tested bio control agents synergized the effect of each other and caused the highest mortality at 25°C and 56% RH. The results clearly demonstrated that I. fumosorosea and new enhanced DEBBM can be integrated to be an effective control measure for R. dominica in stored wheat.  相似文献   
66.
Intracellular free calcium is regulated by Ca++-ATPase, one form present on the plasma membrane (PM Ca++-ATPase) and the other on sarcoplasmic (endoplasmic) reticulum (SR/ER Ca++-ATPase). An endogenous inhibitor of SR Ca++-ATPase from human placenta was shown to be present in normal placenta and the activity was not detectable in placenta from preeclamptic patients. The inhibitor was distributed in cytosol and microsomes. The inhibition of Ca++-ATPase by this inhibitor was concentration-and time-dependent. The inhibitor neither bound to DEAE-nor CM-sepharose resins at pH 7.5 and 8.5. Furthermore, it was heat stable for 15min up to 55°C and completely destroyed at 80°C in a few minutes. It was also observed to be stable at room temperature for at least 3 months. The purification and characterization of this inhibitor would be valuable in achieving an understanding of the normal regulation of Ca++-ATPase in the placenta during pregnancy.  相似文献   
67.
Two populations of cogongrass [Imperata cylindrica (L.) Raeuschel], one from the saline regions of the Salt Range and the other from the non-saline regions of Faisalabad were assessed for salinity tolerance on the basis of some key morphological and physiological attributes. It was hypothesized that the tolerant population from the Salt Range must have developed some specific structural modifications, which are responsible for its better survival under high salinities. These adaptive components can be effectively used in modern technologies for improving degree of tolerance of other sensitive crops. The population from the Salt Range markedly excelled the Faisalabad population in terms of growth and physiological attributes measured in this study. The Faisalabad population of I. cylindrica was unable to survive at the highest salt level (200 mM NaCl). The tolerance of the Salt Range population to salt stress was found to be related to high accumulation of organic osmotica, particularly total free amino acids and proline as well as Ca2+ in the shoot. The distinctive structural modifications in the Salt Range population were found to be enhanced succulence, well-developed bulliform cells in leaves and smaller stomatal area.  相似文献   
68.

Objective

To study the putative effects of Advanced Oxidation Protein Products (AOPPs) and Advanced Glycation End Products (AGEs) in the development and progression of cardiovascular disease (CVD).

Methodology

AGEs, AOPPs, e-NOS, lipid profile, circulating stress and inflammatory biomarkers were evaluated among fifty cardiovascular patients and fifty controls. Independent student’s t-test was done for statistical analysis.

Results

The malondialdehyde mean level in CVD patients (5.45?nmol/ml) was significantly higher than control (1.36?nmol/ml) (p value?=?0.018). Nitric oxide in CVD patients (55.72?ng/ml) was remarkably increased as compared to normal subjects (19.19?ng/ml). A significant change in the mean serum level of AGEs in CVD patients (2.74?ng/ml) and normal individuals (0.85?ng/ml) was recorded (p value?=?0.000). The AOPPs also showed significant increased levels in CVD group (132.07?ng/ml) in comparison with normal subjects (83.05?ng/ml) (p value?=?0.011). The mean eNOS serum level in CVD group (15.50?U/L) was higher than control group (11.28?U/L) (p value?=?0.004). Cardiovascular disease patients, in comparison with healthy controls, showed increased level of total cholesterol (5.48?mmol/L vs 4.45?mmol/L), triglycerides (2.59?mmol/L vs 1.24?mmol/L), and low density lipoprotein (2.47?mmol/L vs 2.31?mmol/L) along with decrease in high density lipoprotein (1.39?mmol/L vs 1.74?mmol/L). The mean MMP-11 serum levels in CVD group (98.69?ng/ml) was almost double of control group (45.60?ng/ml) (p value?=?0.017). The mean serum level of TNF-α and IL1-α were 32.16?pg/ml and 6.64?pg/ml in CVD patient. The significant decreasing trend of SOD (p value?=?0.041), CAT (p value?=?0.018), GSH (p value?=?0.036) and GRx (p value?=?0.029) but increasing drift of GPx (0.023) level was observed in CVD patients.

Conclusion

This study provides strong evidence that CVD patients presented with elevated oxidative stress, enhanced inflammation and lipid profile in their serum. Therefore, the study strongly approves that AGEs, AOPPs, inflammatory and lipoxidative biomarkers hold predictive potential in causing and aggravating the disease, thus by controlling these factors CVD progression can be inhibited.  相似文献   
69.
Transgenic Research - Most of the commercialized insect resistant transgenic crops express cry gene(s) isolated from Bacillus thuringiensis; however, intensive cultivation of Bt crops over almost...  相似文献   
70.
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