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274622. Effects of L-arginine on prevention and treatment of lithium-pilocarpine-induced status epilepticus
- Creator:
- Noyan, B. and Güleç, G.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, oxid dusný, nitrous oxide, L-arginine, status epilepticus, rat, 14, and 612
- Language:
- English
- Description:
- The effects of various doses of L-arginine, a nitric oxide substrate, on lithium-pilocarpine-induced seizures were studied in rats. Rats were implanted with chronic, stainless steel screw electrodes epidurally for electrocortical recordings. A control group received 3 mEq/kg LiCl (i.p.) and 24 h later 45 mg/kg pilocarpine HCl (i.p.). Two different experimental procedures were followed: (1) L-arginine was applied in doses of 100 mg/kg, 300 mg/kg or 500 mg/kg (i.p.), 30 min before pilocarpine injection; (2) 300 mg/kg, 500 mg/kg or 1000 mg/kg (i.p.) L-arginine was injected either 5 min or 30 min after the onset of status epilepticus (SE). L-arginine (300 mg/kg) injected 30 min before pilocarpine significantly reduced the percentage of SE, but did not change the latency to SE or 24-hour survival. These parameters were not significantly affected by the 100 mg/kg or 500 mg/kg dose of L-arginine. On the other hand, no dose of L-arginine that was applied after SE had begun, had any significant influence on the seizures. We concluded that L-arginine may prevent seizure activity in some but not all doses, and does not have any effect on the ongoing seizure activity., B. Noyan, G. Güleç., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
274623. Effects of L-malate on mitochondrial oxidoreductases in liver of aged rats
- Creator:
- Wu, J.-L., Wu, Q.-P., Peng, Y.-P., and Zhang, J.-M.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, stárnutí, mitochondrie, aging, mitochondrias, L-malate, electron transport chain, 14, and 612
- Language:
- English
- Description:
- Accumulation of oxidative damage has been implicated to be a major causative factor in the decline in physiological functions that occur during the aging process. The mitochondrial respiratory chain is a powerful so urce of reactive oxygen species (ROS), considered as the pathogen ic agent of many diseases and aging. L-malate, a tricarboxylic acid cycle intermediate, plays an important role in transporting NADH from cytosol to mitochondria for energy production. Previous studies in our laboratory reported L-malate as a free radical scavenger in aged rats. In the present study we focused on the effect of L-malate on the activities of electron transport chain in young and aged rats. We found that mitochondrial membrane potential (MMP) and the activities of succinate dehydrogenase, NADH-cytochrome c oxidoreductase and cytochrome c oxidase in liver of aged rats were significantly decreased when compared to young control rats. Supplementation of L-malate to aged rats for 30 days slightly increased MMP and improved the activities of NADH-dehydrogenase, NADH-cytochrome c oxidoreductase and cytochrome c oxidase in liver of aged rats when compared with aged control rats. In young rats, L-malate administration increased only the activity of NADH-dehydrogenase. Our result suggested that L-malate could improve the activities of electron transport chain enzymes in aged rats., J.-L. Wu ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
274624. Effects of L-malate on physical stamina and activities of enzymes related to the malate-aspartate shuttle in liver of mice
- Creator:
- Wu, J. L., Wu, Qingping, Huang, J. M., Chen, R., Cai, M., and Tan, J. B.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, biochemie, mitochondrie, biochemistry, mitochondrias, L-malate, tricarboxylic acid cycle, malate-aspartate shuttle, malate dehydrogenase, aspartate dehydrogenase, 2, and 577
- Language:
- English
- Description:
- L-malate, a tricarboxylic acid cycle (TCA ) intermediate, plays an important role in transporting NADH from cytosol to mitochondria for energy production and may be involved in the beneficial effects of improving physical stamina. In the present study, we investigated the effects of L-malate on the performance of forced swimming time and blood biochemical parameters related to fatigue – blood urea nitrogen (BUN), glucose (Glc), creatine kinase (CK) , total protein (TP) and lactic acid (LA). To investigate the effects of L-malate on the malate-aspartate shuttle and energy metabolism in mice, the activities of enzymes related to the malate-aspartate shuttle were measured. L-malate was orally administered to mice continuously for 30 days using a feeding atraumatic needle. The swimming time was increased by 26.1 % and 28.5 %, respectively, in the 0.210 g/kg and 0.630 g/kg L-malate-treated group compared with the control group. There were no differences in the concentrations of Glc, BUN and TP between the L-malate-treated groups and the control groups. However, the levels of CK were significantly decreased in the L-malate-treated groups. The results predict a potential benefit of L-malate for improving physical stamina and minimizing muscle damage during swimming exercise. The activities of cytosolic and mitochondrial malate dehydrogenase were significantly elevated in the L-malate-treated group compared with the control group. These enzymatic activities may be useful indicators for evaluating changes affecting the malate-aspartate shuttle and energy metabolism in the liver of mice., J. L. Wu, Q. P. Wu, J. M. Huang, R. Chen, M. Cai, J. B. Tan., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
274625. Effects of larval diapause and the juvenile hormone analog, fenoxycarb, on testis development and spermatogenesis in the wax moth, Galleria mellonella (Lepidoptera: Pyralidae)
- Creator:
- Bebas, Piotr, Bronisław Cymborowski, Kazek, Michalina, and Polanska, Marta Anna
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- motýli, zavíječovití, zavíječ voskový, spermatogeneze, butterflies, Pyralidae, Galleria mellonella, spermatogenesis, Lepidoptera, wax moth, juvenile hormone analogs, larval diapause, larval testes, vas deferens, 2, and 59
- Language:
- English
- Description:
- Facultative diapause in the wax moth, Galleria mellonella, occurs in the final larval instar. Application of juvenile hormone analogs (JHAs) to the larvae of this species has similar effects to diapause, in terms of prolonged development of the larval stages and the arrest in the metamorphosis of internal organs. Here, we focus on testes development and spermatogenesis at the end of larval development in G. mellonella, how they are affected by diapause induced by an environmental decrease in temperature to 18°C and the application of a JHA (fenoxycarb) to larvae. Because neither testis development nor spermatogenesis are described in detail for this species, we examined them in individuals not in diapause during the period from the last larval instar to the newly emerged adult and present a timetable of changes that occur in the development of testes in this species. These observations have increased the very limited data on the course of spermatogenesis in pyralid insects. We then used these data for comparative analysis of testes in larvae from two experimental groups: individuals in diapause and those treated with fenoxycarb. The results on the general morphology testes revealed obvious degenerative changes caused by fenoxycarb (but not by diapause), including testicular wall hypertrophy and disarrangement of testicular follicles. Moreover, treatment with fenoxycarb finally resulted in the disintegration of nearly all testicular cyst-containing germ cells at different stages of spermatogenesis, a situation never previously described in the literature. In contrast, the main effect of diapause on testes was merely the degeneration of spermatocytes in the proximal regions of the testicular follicles. Finally, the TUNEL analyses, revealed that the degenerative changes in germ cells were apoptotic in character in the testes of both individuals in diapause and fenoxycarb-treated males., Piotr Bebas, Bronislaw Cymborowski, Michalina Kazek, Marta Anna Polanska., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274626. Effects of larval diet on female reproductive output of the European coccinellid Adalia bipunctata and the invasive species Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Ware, Remy L., Yguel, Benjamin, and Majerus, Michael E.N.
- Type:
- article, model:article, and TEXT
- Subject:
- Adalia bipunctata, aphidophagous guilds, cannibalism, Coccinellidae, Harmonia axyridis, intraguild predation, invasive species, larval diet, oviposition, ovariole number, reproductive fitness, and resource competition
- Language:
- English
- Description:
- Cannibalism and intraguild predation (IGP) are both common phenomena amongst aphidophagous coccinellids and serve as vital alternative feeding strategies which can prolong survival during periods of aphid scarcity. A reduction in essential prey density and the acceptance of conspecific or heterospecific prey are likely to have a considerable influence on both larval development and adult reproduction. However, little is known about the legacy of larval diet on adult performance. This paper considers the effects of the diet provided to larvae of Harmonia axyridis (Pallas) and Adalia bipunctata (Linnaeus) (Coleoptera: Coccinellidae) on the reproductive output of the resulting females. Results showed that larval diets, including treatments analogous to competition and IGP, did not affect adult longevity, ovipositional lag, proportion of eggs laid in clutches or ovariole number in H. axyridis or A. bipunctata. However, some variation in the maximum clutch size and oviposition rate was seen. A larval diet of unlimited aphids resulted in the largest clutches of eggs being laid by both species. The total number of eggs laid over 30 days was largest for H. axyridis when larvae were reared on unlimited aphids or limited aphids supplemented with either conspecific or heterospecific eggs, whereas oviposition was lower for A. bipunctata females that had received conspecific or heterospecific eggs in their larval diets. The results have also enabled us to make some general comparisons of reproductive parameters between the two species, and to refute the hypothesis that the maximum clutch size laid by a female ladybird is limited by the number of ovarioles within an ovary. We conclude that IGP of A. bipunctata eggs by H. axyridis larvae has a positive effect on reproductive output and is therefore likely to further contribute to the spread and increase of H. axyridis in Britain.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274627. Effects of leaf-to-fruit ratio on chlorophyll fluorescence parameters of walnut (Juglans regia L.) leaves
- Creator:
- Zhang, C. F., Pan, C. D., and Chen, H.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- defoliace, ovocné stromy, defoliation, fruit trees, photochemical efficiency of PSII, 2, and 581
- Language:
- Multiple languages
- Description:
- In this study, we investigated maximal quantum yield of PSII photochemistry(Fv/Fm),effective quantum yield of PSII photochemistry (ΦPSII), and nonphotochemical quenching (NPQ) of walnut (Juglans regia ‘Xinxin2’) leaves with different leaf-to-fruit ratios (LFRs). The results indicated that the increasing LFR increased the values of Fv/Fm, ΦPSII, and NPQ in leaves on the girdled shoot with one and two leaves, and decreased the values of Fv/Fm and ΦPSII in leaves on the girdled shoot with five leaves, whereas had no effect on the chlorophyll (Chl) fluorescence in leaves on the girdled shoot with three and four leaves. These results indicate that the effects of LFR on Chl fluorescence depend on a LFR range and show a transitional trend transition, and that excessive fruit load accelerates leaf senescence resulting in the destruction of the reaction center in PSII., C. F. Zhang, C. D. Pan, H. Chen., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
274628. Effects of leukaemia inhibitory factor receptor on the early stage of osteogenic differentiation of human bone marrow mesenchymal cells
- Creator:
- T., Yan, R. Q., Xu, X. Y., Cao, L. L., J. Y., Zheng, M. R., and Li, W. D.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- leukaemia inhibitory factor receptor, osteogenic differentiation, and human bone marrow mesenchymal sten cells
- Language:
- English
- Description:
- Leukaemia inhibitory factor (LIF) has a wide variety of biological activities. While recent studies have focused on the role of LIF in osteoblast differentiation, the exact role of LIFR during the early stage of osteogenic differentiation remains unclear. We observed that LIFR expression gradually decreased during the early stage of osteogenic differentiation of hMSCs. To evaluate how LIFR regulates osteogenic differentiation in greater depth, we transfected hMSCs with LIFR overexpression and siRNA lentiviral plasmids. Cells were divided into four groups:a negative overexpression control group, a LIFR overexpression group, a negative siRNA control group, and a LIFR siRNA group. On different days (0, 3, and 6) of the osteogenic differentiation of hMSCs, alkaline phosphatase (ALP) activity was assayed with an ALP staining and activity assay kit. Cells were harvested to assess the mRNA and protein expression of LIF, LIFR, and osteogenesis-related factors (ALP; RUNX2; osteonectin) by qRT-PCR and western blot analyses, respectively. In addition, culture supernatants were tested for the LIF content by ELISA. Our results showed that overexpression of LIFR significantly suppressed the osteoblast differentiation of hMSCs. In contrast, LIFR siRNA markedly improved this osteoblast differentiation as determined by ALP staining and activity measurements. Moreover, RUNX2, ALP, and ONN expre-sion was also significantly changed by altering LIFR expression. We further analysed the expression of LIF and LIFR, revealing consistent LIF and LIFR trends during the osteogenic differentiation of hMSCs. Together, these results suggested that LIFR may be a novel negative regulator during the early stage of hMSC osteogenic differentiation. and Corresponding authors: Tao Wang, Meirong Zheng, Weidong Li
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274629. Effects of light intensity and temperature on the photosynthetic irradiance response curves and chlorophyll fluorescence in three picocyanobacterial strains of Synechococcus
- Creator:
- Jodłowska, S. and Śliwińska, S.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, fluorescence, teplota, photosynthesis, temperature, irradiance, photoacclimation, picocyanobacteria, 2, and 581
- Language:
- Multiple languages
- Description:
- Chrococcoid cyanobacteria of the genus Synechococcus are the important component of marine and freshwater ecosystems. Picocyanobacteria comprise even 80% of total cyanobacterial biomass and contribute to 50% of total primary cyanobacterial bloom production. Chlorophyll (Chl) fluorescence and photosynthetic light response (P-I) curves are commonly used to characterize photoacclimation of Synechococcus strains. Three brackish, picocyanobacterial strains of Synechococcus (BA-132, BA-124, BA-120) were studied. They were grown under 4 irradiances [10, 55, 100, and 145 μmol(photon) m-2 s-1] and at 3 temperatures (15, 22.5, and 30°C). Photosynthetic rate was measured by Clark oxygen electrode, whereas the Chl fluorescence was measured using Pulse Amplitude Modulation fluorometer. Based on P-I, two mechanisms of photoacclimation were recognized in Synechococcus. The maximum value of maximum rate of photosynthesis (Pmax) expressed per biomass unit at 10 μmol(photon) m-2 s-1 indicated a change in the number of photosynthetic units (PSU). The constant values of initial slope of photosynthetic light response curve (α) and the maximum value of Pmax expressed per Chl unit at 145 μmol(photon) m-2 s-1 indicated another mechanism, i.e. a change in PSU size. These two mechanisms caused changes in photosynthetic rate and its parameters (compensation point, α, saturation irradiance, dark respiration, Pmax) upon the influence of different irradiance and temperature. High irradiance had a negative effect on fluorescence parameters, such as the maximum quantum yield and effective quantum yield of PSII photochemistry (φPSII), but it was higher in case of φPSII., S. Jodłowska, S. Śliwińska., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
274630. Effects of light quality on growth and development, photosynthetic characteristics and content of carbohydrates in tobacco (Nicotiana tabacum L.) plants
- Creator:
- Yang, L. Y., Wang, L. T., Ma, J. H., Ma, E. D., Li, J. Y., and Gong, M.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- morfogeneze, světlo, morphogenesis, light, fluorescence chlorofylu, obsah sacharidů, růst, Nicotiana tabacum, chlorophyll fluorescence, content of carbohydrates, growth, 2, and 581
- Language:
- Multiple languages
- Description:
- In this study, effects of yellow (Y), purple (P), red (R), blue (B), green (G), and white (W) light on growth and development of tobacco plants were evaluated. We showed that monochromatic light reduced the growth, net photosynthetic rate (PN), stomatal conductance, intercellular CO2, and transpiration rate of tobacco. Such a reduction in PN occurred probably due to the stomatal limitation contrary to plants grown under W. Photochemical quenching coefficient (qP), maximal fluorescence of dark-adapted state, effective quantum yield of PSII photochemistry (ΦPSII), and maximal quantum yield of PSII photochemistry (Fv/Fm) of plants decreased under all monochromatic illuminations. The decline in ΦPSII occurred mostly due to the reduction in qP. The increase in minimal fluorescence of dark-adapted state and the decrease in Fv/Fm indicated the damage or inactivation of the reaction center of PSII under monochromatic light. Plants under Y and G showed the maximal nonphotochemical quenching with minimum PN compared with the W plants. Morphogenesis of plants was also affected by light quality. Under B light, plants exhibited smaller angles between stem and petiole, and the whole plants showed a compact type, while the angles increased under Y, P, R, and G and the plants were of an unconsolidated style. The total soluble sugar content increased significantly under B. The reducing sugar content increased under B but decreased significantly under R and G compared with W. In conclusion, different monochromatic light quality inhibited plants growth by reducing the activity of photosynthetic apparatus in plants. R and B light were more effective to drive photosynthesis and promote the plant growth, while Y and G light showed an suppression effect on plants growth. LEDs could be used as optimal light resources for plant cultivation in a greenhouse., L. Y. Yang, L. T. Wang, J. H. Ma, E. D. Ma, J. Y. Li, M. Gong., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public