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7492. Effects of phytoplasma infection on growth and photosynthesis in leaves of field grown apple (Malus pumila Mill. cv. Golden Delicious)
- Creator:
- Bertamini, M., Muthuchelian, K., Grando, M. S., and Nedunchezhian, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- amino acids, chlorophyll content and fluorescence, electron donor, nitrate reductase, photosystem, phytoplasma, proteins, ribulose-1,5-biphosphate carboxylase, sugars, and starch
- Language:
- Multiple languages
- Description:
- The contents of chlorophyll (Chl), leaf biomass, and soluble proteins were markedly decreased in phytoplasma infected apple leaves. Similar results were also observed for ribulose-1,5-bisphosphate carboxylase, 14CO2 fixation, and nitrate reductase activity. In contrast, the contents of sugars, starch, amino acids, and total saccharides were significantly increased in phytoplasma infected leaves. In isolated chloroplasts, phytoplasma infection caused marked inhibition of whole photosynthetic electron chain and photosystem 2 (PS2) activity. The artificial exogenous electron donor, diphenyl carbazide, significantly restored the loss of PS2 activity in infected leaves. Similar results were obtained when Fv/Fm was evaluated by in vivo Chl a fluorescence kinetic measurements. and M. Bertamini ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7493. Effects of pioglitazone on ventricular myocyte shortening and Ca2+ transport in the Goto-Kakizaki type 2 diabetic rat
- Creator:
- Salem, K. A, Sydorenko, V, Howarth, F. C, Oz, M, and Qureshi, M
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fyziologie člověka, human physiology, Type 2 diabetes mellitus, Goto-Kakizaki rat, Ventricular myocytes, Calcium transport, Pioglitazone, 14, and 612
- Language:
- English
- Description:
- Pioglitazone (PIO) is a thiazolidindione antidiabetic agent which improves insulin sensitivity and reduces blood glucose in experimental animals and treated patients. At the cellular level the actions of PIO in diabetic heart are poorly understood. A previous study has demonstrated shortened action potential duration and inhibition of a variety of transmembrane currents including L-type Ca2+ current in normal canine ventricular myocytes. The effects of PIO on shortening and calcium transport in ventricular myocytes from the Goto-Kakizaki (GK) type 2 diabetic rat have been investigated. 10 min exposure to PIO (0.1-10 μM) reduced the amplitude of shortening to similar extents in ventricular myocytes from GK and control rats. 1 μM PIO reduced the amplitude of the Ca2+ transients to similar extents in ventricular myocytes from GK and control rats. Caffeine-induced Ca2+ release from the sarcoplasmic reticulum and recovery of Ca2+ transients following application of caffeine and myofilament sensitivity to Ca2+ were not significantly altered in ventricular myocytes from GK and control rats. Amplitude of L-type Ca2+ current was not significantly decreased in myocytes from GK compared to control rats and by PIO treatment. The negative inotropic effects of PIO may be attributed to a reduction in the amplitude of the Ca2+ transient however, the mechanisms remain to be resolved., K. A. Salem, V. Sydorenko, M. Qureshi, M. Oz, F. C. Howarth., and Seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7494. Effects of pleuran (β-glucan isolated from Pleurotus ostreatus) on experimental colitis in rats
- Creator:
- Viera Nosáľová, Pavel Bobek, Silvia Černá, Štefan Galbavý, and Svetoslav Štvrtina
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, glukany, glucans, pleuran, acetic acid induced colitis, rats, 14, and 612
- Language:
- English
- Description:
- The effects of pleuran, ß-1,3 glucan isolated from Pleurotus ostreatus, were studied in a model of acute colitis induced by intracolonic administration of acetic acid. There was a reduction of the colonic damage score, colonic wet weight and wet/dry weight ratio 48 h after single luminal 2 % pleuran suspension pretreatment. Similar results were obtained after repeated intraperitoneal administration of pleuran in doses of 30 and 100 mg/kg. Pleuran given orally as a 10 % food component over 4 weeks was effective in reducing the extent of mucosal damage, but did not prevent the increase of myeloperoxidase in the injured colonic segment. In the segment without macroscopic evidence of inflammation, myeloperoxidase activity was significantly lower as documented by histological examination. The results indicate a possible role of this immunomodulator in the treatment of ulcerative colitis., V. Nosáľová, P. Bobek, S. Černá, Š. Galbavý, S. Štvrtina., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7495. Effects of postharvest pretreatments and preservative solutions on vase life longevity and flower quality of sweet pea (Lathyrus odoratus L.)
- Creator:
- Elhindi, K. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, cut flower, sweet pea, preservative solution, vase life, water relations, 2, and 58
- Language:
- Multiple languages
- Description:
- The effects of postharvest pretreatments on vase life, keeping quality and carbohydrate concentrations in cut sweet pea (Lathyrus odoratus L.) flowers were investigated. Compared to the control, all treatments promoted floret quality and extended longevity. The cut flowers held in the solution containing sucrose + 8-hydroxyquinoline (Suc+HQS) was more effective in promoting absorption rate, achieved greater maximum fresh mass, had better water balance for a longer period, extended the vase life (up to 17 d), and delayed degradation of chlorophylls. The same treatment also enhanced the concentration of soluble carbohydrates in the petals and stems and leaf chlorophyll (Chl) content, whereas it was lowest in silver thiosulphate (STS) treatment. However, concentrations of anthocyanin in the petals were higher for treatment with sucrose or STS plus sucrose than in control or STS alone treatments. Our results suggest that pulse treatment with HQS plus sucrose for 12 h is the most effective for improving pigmentation and use as a commercial cut flower preservative solution to delay flower senescence, enhance quality, and prolong the vase life of sweet pea. The results also showed that soluble carbohydrate concentration in petals and stems is an important factor in determining the vase life of sweet pea flowers., K. M. Elhindi., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7496. Effects of potato virus YNTN infection on gas exchange and photosystem 2 function in leaves of Solanum tuberosum L.
- Creator:
- Zhou, Y. H., Peng, Y. H., Lei, J. L., Zou, L. Y., Zheng, J. H., and Yu, J. Q.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, intercellular CO2 concentration, net photosynthetic rate, photochemistry, photosynthetic electron transport, potato, potato virus Y, quantum yield, and stomatal conductance
- Language:
- Multiple languages
- Description:
- Photosynthetic responses of potato (Solanum tuberosum L. cv. Chunzao) were examined during potato virus Y (PVYNTN) infection. PVYNTN infection significantly reduced net photosynthetic rate and stomatal conductance, but had little influence on intercellular CO2 concentration. As the disease developed, the maximum carboxylation velocity of ribulose-1,5-bisphosphate carboxylase/oxygenase and the maximum electron transport rate contributing to ribulose-1,5-bisphosphate regeneration gradually decreased, followed by substantial reductions in the relative quantum efficiency of photosystem 2 (PS2) electron transport, the efficiency of excitation energy capture by open PS2 reaction centres, and photochemical quenching, but not in sustained photoinhibition. Thus PVYNTN depressed photosynthesis mainly by interfering with the enzymatic processes in the Calvin cycle which resulted in a down-regulation of electron transport. and Y. H. Zhou ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7497. Effects of poverty on impatience: preferences or inattention?
- Creator:
- Bartoš, Vojtěch, Bauer, Michal, Chytilová, Julie, and Levely, Ian
- Publisher:
- CERGE-EI
- Format:
- electronic, bez média, svazek, and 40 stran : ilustrace, tabulky.
- Type:
- model:monograph and TEXT
- Subject:
- Ekonomie, chudoba, rozhodování, experimentální ekonomie, poverty, decision making, experimental economics, 364.662, 159.955.5, 33-028.77, (048.8), 4, and 33
- Language:
- English
- Description:
- Vojtěch Bartoš, Michal Bauer, Julie Chytilová, Ian Levely., Obsahuje bibliografii a bibliografické odkazy, Anglické resumé, and On-line verze: Appendix v rozsahu str. 41-62.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7498. Effects of proline and betaine on heat inactivation of ribulose-1,5-bisphosphate carboxylase/oxygenase in crude extracts of rice seedlings
- Creator:
- Dionisio-Sese, M. L., Shono, M., and Tobita, S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- cultivar differences and Oryza sativa L.
- Language:
- Multiple languages
- Description:
- Activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) in heated crude extracts from seedlings of the rice cultivars Hitomebore and IR28 was investigated in the presence of proline and betaine. Both solutes retarded the inactivation of the enzyme extracted from the leaves of both cultivars at temperature-stress from 35 to 45 °C. At 50 °C, however, betaine was effective in both cultivars. Stabilization of RuBPCO activity was independent of the added solute from 1 to 2 M concentration. and M. L. Dionisio-Sese, M. Shono, S. Tobita.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7499. Effects of rapidly imposed water deficit on photosynthetic parameters of three C4 grasses
- Creator:
- Soares-Cordeiro, A. S., Carmo-Silva, A. E., Bernardes da Silva, A., Marques da Silva, J., Keys, A. J., and Arrabaça, M. C.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll a fluorescence, drought stress, NAD-malic enzyme, NADP-malic enzyme, phosphoenolpyruvate carboxykinase, phosphoenolpyruvate carboxylase, photosynthetic capacity, and Rubisco
- Language:
- Multiple languages
- Description:
- Water deficit, when rapidly imposed on three C4 grasses of the different metabolic subtypes, Paspalum dilatatum Poiret (NADP-malic enzyme), Cynodon dactylon (L.) Pers (NAD-malic enzyme) and Zoysia japonica Steudel (phosphoenolpyruvate carboxykinase), caused decreases in photosynthetic rates, in the quantum yield of PS II and photochemical quenching, and in the activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC). The results provide evidence for non-stomatal limitations of photosynthesis differing in nature between the three species. and A. S. Soares-Cordeiro ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7500. Effects of rate of decrease in power output in decrement-load exercise on oxygen uptake
- Creator:
- Yano, T., Yunoki, T., Matsuura, T., Arimitsu, T., and Kimura, T.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- experimentální fyziologie, kyslík, experimental physiology, oxygen, spotřeba kyslíku, kyslíkový dluh, oxygen uptake, oxygen debt, decrement-load exercise, and rate of decrease in power output
- Language:
- English
- Description:
- The purpose of this study was to examine how oxygen uptake (V.o2) in decrement-load exercise (DLE) is affected by changing rate of decrease in power output. DLE was performed at three different rates of decrease in power output (10, 20 and 30 watts ・min-1: DLE10, DLE20 and DLE30, respectively) from power output corresponding to 90 % of peak V.o2. V.o2 exponentially increased and then decreased, and the rate of its decrease was reduced at low power output. The values of V.o2 in the three DLE tests were not different for the first 2 min despite the difference in power output. The relationship between V.o2 and power output below 50 watts was obtained as a slope to estimate excessive V.o2 (ex-V.o2) above 50 watts. The slopes were 10.0±0.9 for DLE10, 9.9±0.7 for DLE20 and 10.2±1.0 ml ・min-1 ・ watt-1 for DLE30. The difference between V.o2 estimated from the slope and measured V.o2 was defined as ex-V.o2. The peak value of ex-V.o2 for DLE10 (189±116 ml ・min-1) was significantly greater than those for DLE20 and for DLE30 (93±97 and 88±34 ml ・min-1). The difference between V.o2 in DLE and that in incremental-load exercise (ILE) below 50 watts (ΔV.o2) was greater in DLE 30 and smallest in DLE10. There were significant differences in ΔV.o2 among the three DLE tests. The values of ΔV.o2 at 30 watts were 283±152 for DLE10, 413±136 for DLE20 and 483±187 ml ・min-1 for DLE30. Thus, a faster rate of decrease in power output resulted in no change of V.o2 at the onset of DLE, smaller ex-V.o2 and greater ΔV.o2. These results suggest that V.o2 is disposed in parallel in each motor unit released from power output or recruited in DLE., T. Yano, T. Yunoki, R. Matsuura, T. Arimitsu, T. Kimura., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public