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131.
The aim of the present investigation was to evaluate the anti-diabetic activity of 20-OH-ecdysone on glucose metabolic key enzymes in control and streptozotocin induced diabetic rats. On oral administration of 20-OH-ecdysone at a dose of 5mg/kg body weight per day to diabetic rats for 30 days resulted in a significant decrease in the levels of plasma glucose, glycosylated hemoglobin (HbA1c) and an increase in the levels of insulin and hemoglobin. Administration of 20-OH-ecdysone showed significant increase in the levels of glycolytic enzyme (hexokinase) and hepatic shunt enzyme (glucose-6-phosphate dehydrogenase) whereas significant decrease in the levels of gluconeogenic enzymes (glucose-6-phosphatase and fructose-1,6-bisphosphatase) in diabetic treated rats. Furthermore, protection against body weight loss of diabetic animals also observed. This study indicates that the administration of 20-OH-ecdysone to diabetic rats resulted in alterations in the metabolism of glucose with subsequent reduction in plasma glucose levels. A comparison was made between the action of 20-OH-ecdysone and antidiabetic drug-glibenclamide. The effects produced by the 20-OH-ecdysone were comparable to that of glibenclamide. 相似文献
132.
Optimization of media components for the growth and biomass production of Halobacterium salinarum VKMM 013 was carried out using response surface methodology. A second order quadratic model was estimated and media components were determined based on quadratic regression equation generated by model. These were 6.35 g L−1 of KCl, 9.70 g L−1 of MgSO4, 13.38 g L−1 of gelatin and 12.00 g L−1 of soluble starch in nutrient broth supplemented with artificial seawater with 20% (w/v) of NaCl. In these optimal conditions, the obtained cell concentration of 0.746 g L−1 dry weight was in agreement with the predicted cell concentration. The optimized media significantly shortened the time required for cell culture to reach the stationary phase while providing a nearly 2.4-fold increase in biomass production. Furthermore, in cell cultures of three other halophilic archaea the use of optimized media enhanced growth rate and provided high-cell density. 相似文献
133.
Reshmi Rajendran Maria Dolores Ynsa Mark A. Smith Barry Halliwell 《Biochemical and biophysical research communications》2009,382(1):91-95
There is considerable interest in the role of metals such as iron, copper, and zinc in amyloid plaque formation in Alzheimer’s disease. However to convincingly establish their presence in plaques in vivo, a sensitive technique is required that is both quantitatively accurate and avoids isolation of plaques or staining/fixing brain tissue, since these processes introduce contaminants and redistribute elements within the tissue. Combining the three ion beam techniques of scanning transmission ion microscopy, Rutherford back scattering spectrometry and particle induced X-ray emission in conjunction with a high energy (MeV) proton microprobe we have imaged plaques in freeze-dried unstained brain sections from CRND-8 mice, and simultaneously quantified iron, copper, and zinc. Our results show increased metal concentrations within the amyloid plaques compared with the surrounding tissue: iron (85 ppm compared with 42 ppm), copper (16 ppm compared to 6 ppm), and zinc (87 ppm compared to 34 ppm). 相似文献
134.
Al-Kappany YM Rajendran C Ferreira LR Kwok OC Abu-Elwafa SA Hilali M Dubey JP 《The Journal of parasitology》2010,96(6):1115-1118
Cats are important in the epidemiology of Toxoplasma gondii because they are the only hosts that excrete environmentally resistant oocysts in feces. In the present study, 158 feral cats from Giza, Egypt, were examined for T. gondii infection. Antibodies to T. gondii were found in 97.4% with the modified agglutination test. Viable T. gondii was isolated from tissues (brain, heart, tongue) of 115 of 137 cats by bioassay in mice. These isolates were designated TgCatEg 1-115; none of these isolates was virulent to out-bred Swiss Webster mice. Of the 112 seropositive cats whose tissues were bioassayed individually, T. gondii was isolated from the hearts of 83 (74.1%), tongues of 53 (47.3%), and brains of 36 (32.1%). Toxoplasma gondii oocysts were not detected in rectal contents of any of the 158 cats, probably related to high seropositivity (chronic infection) of cats surveyed. The high prevalence of T. gondii in feral cats in Egypt reported here indicates a high environmental contamination with oocysts. 相似文献
135.
You-Cheng Hseu Geng-Ruei Chang Jian-You Pan Peramaiyan Rajendran Dony Chacko Mathew Mei-Ling Li Jiunn-Wang Liao William Tzu-Liang Chen Hsin-Ling Yang 《Journal of cellular physiology》2019,234(4):4125-4139
Antrodia camphorata (AC) exhibits potential for engendering cell-cycle arrest as well as prompting apoptosis and metastasis inhibition in triple-negative breast cancer (TNBC) cells. We performed the current study to explore the anti-epithelial-to-mesenchymal transition (EMT) properties of fermented AC broth in TNBC cells. Our results illustrated that noncytotoxic concentrations of AC (20–60 μg/ml) reversed the morphological changes (fibroblastic-to-epithelial phenotype) as well as the EMT by upregulating the observed E-cadherin expression. Furthermore, we discovered treatment with AC substantially inhibit the Twist expression in human TNBC (MDA-MB-231) cells as well as in those that were transfected with Twist. In addition, we determined AC to decrease the observed Wnt/β-catenin nuclear translocation through a pathway determined to be dependent on GSK3β. Notably, AC treatment consistently inhibited the EMT by downregulating mesenchymal marker proteins like N-cadherin, vimentin, Snail, ZEB-1, and fibronectin; at that same time upregulating epithelial marker proteins like occludin and ZO-1. Bioluminescence imaging that was executed in vivo demonstrated AC substantially suppressed breast cancer metastasis to the lungs. Notably, we found that western blot analysis confirmed that AC decreased lung metastasis as demonstrated by upregulation of E-cadherin expression in biopsied lung tissue. Together with our results support the anti-EMT activity of AC, indicating AC as having the potential for acting as an anticancer agent for the treatment of human TNBC treatment. 相似文献
136.
137.
The distribution, density and species composition of juvenile shrimps were studied in three mangrove zones of Pichavaram, situated on the southeast coast of India. Nine species of shrimps dominated with Metapenaeus monoceros, M. brevicornis and Penaeus indicus were recorded. This shrimp resource was higher in mangrove-lined waters than that in neritic waters. This field observation was experimentally proved using litter bags. The average catch around the litter bags was 0.80 individuals day–1 for Rhizophora leaves, 1.6 ind. day–1 for Avicennia leaves and 0.16 ind. day–1 in control. In general, abundance of juvenile shrimps was the highest around the leaves that were decomposed for 40 days and colonized with high counts of nitrogen-fixing azotobacters. Finally, a vegetation trap technique using mangrove leaves has been proposed for efficient schooling of juvenile shrimps. There was about 3-fold increase in number of shrimp juveniles around the trap than at control waters. 相似文献
138.
Mazhar Ali Nasir Masood Hafiz Muhammad Rashad Javeed Ibrahim Al-Ashkar Khalid F. Almutairi Liyun Liu Muhammad Aqeel Sarwar Karthika Rajendran Ayman EL Sabagh 《Phyton》2022,91(10):2235-2248
Soil amendments containing carbonized materials increase the soil carbon reservoir, influence plant productivity,
and, ultimately, help to clean the environment. There is data on the effect of such additions on soil physicochemical
properties or plant growth, but few studies have focused on how these carbonized materials are distributed by termite species in the soil ecosystem. It is the first comprehensive study of the transportation of biochar (BC) by termite
species under tropical environmental conditions in Pakistan. The present study was carried out to test the hypothesis
that if termite species I) were involved in the distribution of biochar particles II) if yes, then how far these particles
were transported during the study period (10 days) and III) check their preference between the enriched BC (EBC)
and non-enriched BC. BC was enriched with the cattle slurry after its pyrolysis in the study. The results showed that
EBC particles were significantly more widely distributed than non-enriched BC particles, but both types of BC were
transported more than 4 cm (ring 4) within 10 days (at the end of the experiment). The current study also revealed
that EBC was easily attached to the setae, cuticle, and legs of termites, implying that it could potentially be transported over a greater distance. Furthermore, transportation of EBC over larger distances indicated a potential preference of termite species between the EBC and BC particles. During the study, however, the preference among the
termite species was also observed. Under the prevailing study conditions, the Coptotermes heimi and Heteroterme
indicola species transported the EBC further than Microtermes obesi and Odontotermes obesus. These findings
revealed that transportation preferences were observed among the four termite species. In conclusion, the current
study found that termites were involved in the distribution of BC particles, with a preference for EBC and that these
have the potential to transport BC particles more than 4 cm within 10 days. Furthermore, two species Coptotermes
heimi and Heteroterme indicola may be more suitable candidates for EBC transpiration in Pakistani soils. It was
necessary to conduct additional research into the effect of temperature on the transportation process. 相似文献
139.
The R-peak detection is crucial in all kinds of electrocardiogram (ECG) applications. However, almost all existing R-peak detectors suffer from the non-stationarity of both QRS morphology and noise. To combat this difficulty, we propose a new R-peak detector, which is based on the new preprocessing technique and an automated peak-finding logic. In this paper, we first demonstrate that the proposed preprocessor with a Shannon energy envelope (SEE) estimator is better able to detect R-peaks in case of wider and small QRS complexes, negative QRS polarities, and sudden changes in QRS amplitudes over that using the absolute value, energy value, and Shannon entropy features. Then we justify the simplicity and robustness of the proposed peak-finding logic using the Hilbert-transform (HT) and moving average (MA) filter. The proposed R-peak detector is validated using the first-channel of the 48 ECG records of the MIT-BITH arrhythmia database, and achieves average detection accuracy of 99.80%, sensitivity of 99.93% and positive predictivity of 99.86%. Various experimental results show that the proposed R-peak detection method significantly outperforms other well-known methods in case of noisy or pathological signals. 相似文献
140.
Sathesh kanna Velli Jagan Sundaram Manikandan Murugan Gopalakrishnan Balaraman Devaki Thiruvengadam 《Journal of biochemical and molecular toxicology》2019,33(10)
Vanillic acid (VA) is found in high concentrations in various plants and used as traditional medicine for various diseases. The aim of the existing study is to illustrate the protective effects of VA against benzo(a)pyrene (B(a)P)‐induced lung cancer in Swiss albino mice. B(a)P (50 mg/kg b.wt.) was given orally to induce lung cancer in mice. The body weight, tumor incidence, carcinoembryonic antigen (CEA), neuron‐specific enolase (NSE), and enzymatic/nonenzymatic antioxidants (superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase, and glutathione) were estimated. Further histochemical investigation through hematoxylin and eosin staining was also carried out. B(a)P administered groups showed increased levels of serum pathological markers CEA, NSE along with reduced final body weight as well as decreased tissue enzymatic and nonenzymatic antioxidants activities, whereas VA treatment (200mg/kg/b.wt) along with B(a)P showed significantly reverted the above changes, which proves as prominent anticancer effects in experimentally induced lung cancer. Overall, these results suggest that VA has an efficient preventive action against B(a)P‐induced lung cancer, and this is attributed to its free‐radical scavenging antioxidant activities. 相似文献