scholarly journals Effects of Initial Inorganic Ion Composition and Initial Totala Inorganic Ion Concentration of Culture Medium on the Net Photosynthetic Rate and Growth of Strawberry Plantlets In Vitro under Photoautotrophic Conditions.

1995 ◽  
Vol 33 (1) ◽  
pp. 71-77 ◽  
Author(s):  
Chan Suk YANG ◽  
Toyoki KOZAI ◽  
Kazuhiro FUJIWARA
Keyword(s):  
Net Photosynthetic Rate ◽  
Photosynthetic Rate ◽  
Culture Medium ◽  
Ion Concentration ◽  
Ion Composition ◽  
Inorganic Ion

scholarly journals Response of in vitro Cultured Palm Oil Seedling Under Saline Condition to Elevated Carbon Dioxide and Photosynthetic Photon Flux Density

2012 ◽  
pp. 52-64
Author(s):  
Pet Roey Pascual ◽  
Krienkai Mosaleeyanon ◽  
Kanokwan Romyanon ◽  
Chalermpol Kirdmanee
Keyword(s):  
Stomatal Conductance ◽  
Net Photosynthetic Rate ◽  
Elevated Co2 ◽  
Photosynthetic Rate ◽  
Transpiration Rate ◽  
Pigment Contents ◽  
Salinity Levels ◽  
Oil Palms ◽  
Ambient Co2

Salt stress elicits various physiological and growth responses of oil palm. A laboratory experiment was conducted to determine the responses of oil palms cultured in vitro under varying salinity levels (0, 85.5, 171.11, 342.21 and 684.43 mM NaCl) to elevated CO2 (1000 μmol CO2/mol) and PPFD (100±5 μmol m-2s-1) in terms of growth characteristics, pigment contents and photosynthetic abilities. After 14 days of culture, net photosynthetic rate (μmol CO2 m-2s-1) of oil palms across varying salinity levels was 5.33 times higher than those cultured under ambient CO, (380±100 Mmol CO2/mol) and PPFD (50±5 μmol m-2s -1). At increased net photosynthetic rate (elevated CO2 and PPFD), despite having no significant difference in pigment contents (chlorophyll a, chlorophyll b, total chlorophyll and carotenoid) between different CO2 and PPFD levels, dry weight and percent dry matter were 0.26 and 0.11 times higher, respectively, as compared to those cultured under ambient CO2 and PPFD. In the same elevated CO2 and PPFD level, across all salinity levels, stomatal conductance was 0.30 times lower than those cultured under ambient CO2 and PPFD. At reduced stomatal conductance (elevated CO2 and PPFD), transpiration rate was also reduced by 0.30 times. Thus with increased net photosynthetic rate and reduced transpiration rate, water use efficiency was increased by 7.22 times, across all salinity levels, than those cultured at ambient CO2 and PPFD. These were considered essential for NaCl produces iso-osmotic stress.

STUDIES ON THE MECHANISM OF SECRETION OF CORTICOSTEROIDS BY THE ISOLATED PERFUSED ADRENAL OF THE RAT

1981 ◽  
Vol 91 (2) ◽  
pp. 313-323 ◽  
Author(s):  
C. P. SIBLEY ◽  
B. J. WHITEHOUSE ◽  
G. P. VINSON ◽  
C. GODDARD ◽  
E. McCREDIE
Keyword(s):  
Culture Medium ◽  
Ion Concentration ◽  
Acth Stimulation ◽  
Steroid Production ◽  
Simple Diffusion ◽  
Corticosterone Secretion ◽  
Complex Process ◽  
Doc Production ◽  
Different Levels

A technique for the perfusion of the rat adrenal cortex is described. With tissue culture Medium 199 the preparation was responsive in terms of steroid production to both ACTH and K+ ions. Production of corticosterone and 18-hydroxydeoxycorticosterone (18-hydroxy-DOC) was stimulated by ACTH when it was administered at rates between 5 μu./min and 5 mu./min. Increasing the K+ ion concentration of the perfusate from 3·6 to 5·4 and 8·9 mmol/l stimulated the production of aldosterone, 18-hydroxycorticosterone and deoxycorticosterone, although not of corticosterone or 18-hydroxy-DOC. This preparation has been used to study further the mechanism of secretion of corticosterone and 18-hydroxy-DOC. Thus, production of these two steroids was measured at different perfusion flows, varying between 0·1 and 0·6 ml/min, with different levels of ACTH stimulation. Corticosterone production was significantly (P < 0·001) increased by increasing flows both under control conditions and when ACTH was administered at constant rates of 50 μu./min or 1 mu./min. Production of 18-hydroxy-DOC was not affected by flow either under control conditions or with 50 μu. ACTH/min. However, when ACTH was administered at 1 mu./min, 18-hydroxy-DOC production was also significantly (P < 0·001) increased by flow. The results are consistent with those obtained in previous in-vitro studies and have been interpreted as suggesting that the main mechanism of corticosterone secretion is simple diffusion. In contrast, 18-hydroxy-DOC secretion, at least at sub-maximal levels of stimulation, appears to require a more complex process.

Do novel cement-type biomaterials reveal ion reactivity that affects cell viability in vitro?

2014 ◽  
Vol 9 (3) ◽  
pp. 277-289 ◽  
Author(s):  
Agata Przekora ◽  
Joanna Czechowska ◽  
Dawid Pijocha ◽  
Anna Ślósarczyk ◽  
Grażyna Ginalska
Keyword(s):  
Culture Medium ◽  
Cultured Cells ◽  
Diffraction Method ◽  
Ion Concentration ◽  
Filler Materials ◽  
Cement Type ◽  
Ion Interactions ◽  
Surrounding Environment ◽  
Calcium Magnesium

AbstractCalcium phosphate bioceramics have been studied as bone filler materials for years and have become a component of many commercial products. It is widely known that surface-reactive biomaterials may cause changes in the concentration of crucial ions in the surrounding environment, thereby affecting cell metabolism and viability. The aim of this study was to produce five cement-type biomaterials and characterize their phase composition using X-ray diffraction method, and porosity and pore size distribution using mercury intrusion porosimeter. We then evaluated ion interactions of the novel biomaterials with the surrounding environment (culture medium). A commercially available bone substitute, HydroSet™ (Stryker®), was used as a reference. MTT and NRU cytotoxicity tests were performed to assess the effect of changes in the concentration of crucial ions (calcium, magnesium, phosphate) on osteoblast metabolism and viability in vitro. Our study clearly indicated that various biomaterials demonstrated different ion reactivity and consequently may cause changes in ion concentration in the local environment. Critically low or high values of calcium, magnesium, and phosphate concentrations in the medium exerted cytotoxic effects on the cultured cells. Moreover, we discovered that the chemical composition of the culture medium had a substantial influence on ion interactions with biomaterials.

Effects of LEDs on net photosynthetic rate, growth and leaf stomata of chrysanthemum plantlets in vitro

2004 ◽  
Vol 101 (1-2) ◽  
pp. 143-151 ◽  
Author(s):  
Sun-Ja Kim ◽  
Eun-Joo Hahn ◽  
Jeong-Wook Heo ◽  
Kee-Yoeup Paek
Keyword(s):  
Net Photosynthetic Rate ◽  
Photosynthetic Rate

scholarly journals Simulation of the Time Courses of CO2 Concentration in the Culture Vessel and Net Photosynthetic Rates of Potato Plantlets Cultured Photoautotrophically and Photomixotrophically in Vitro under Different Lighting Cycles

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 515F-515
Author(s):  
Genhua Niu ◽  
Makio Hayashi ◽  
Toyoki Kozai
Keyword(s):  
Net Photosynthetic Rate ◽  
Photosynthetic Rate ◽  
Quantitative Relationship ◽  
Dry Weight ◽  
Co2 Concentration ◽  
Ventilation Rate ◽  
Culture Vessel ◽  
Time Courses ◽  
Potato Plantlets

Potato (Solanum tuberosum L. cv. Benimaru) plantlets were cultured under four lighting cycles (photoperiod/dark period: 16 h/8 h, 4 h/2 h, 1 h/0.5 h, and 0.25 h/0.125 h) photoautotrophically (without sugar in the medium), and photomixotrophically (with sugar in the medium) in vitro for 28 days. Simulations of time courses of CO2 concentration in the vessel (Ci) and dry weight accumulation of the plantlets cultured photoautotrophically were conducted using a previously developed model (Niu and Kozai, 1997). While underestimation and overestimation of time courses of Ci in some treatments were observed, the simulated results of Ci and dry weight accumulation of the plantlets generally agreed with the measured ones. The difference of net photosynthetic rate response to Ci throughout the culture period was examined between the plantlets cultured photoautotrophically and photomixotrophically. Quantitative relationship between daily net photosynthetic rate (daily net production) and vessel ventilation rate per plantlet was simulated under various CO2 levels outside the vessel for given sizes of potato plantlets cultured photoautotrophically in vitro to aid appropriate CO2 enrichment and vessel design in commercial micropropagation.

scholarly journals Growth and Net Photosynthetic Rate of Tomato Plantlets during Photoautotrophic and Photomixotrophic Micropropagation

HortScience ◽  
2001 ◽  
Vol 36 (1) ◽  
pp. 49-52 ◽  
Author(s):  
Chieri Kubota ◽  
Natsuko Kakizaki ◽  
Toyoki Kozai ◽  
Koichi Kasahara ◽  
Jun Nemoto
Keyword(s):  
Net Photosynthetic Rate ◽  
Photosynthetic Rate ◽  
Dry Weight ◽  
Ventilation Rate ◽  
Photon Flux ◽  
Leaf Removal ◽  
Photosynthetic Photon Flux ◽  
Photoautotrophic Micropropagation ◽  
Number Of Leaves

Nodal explants of tomato (Lycopersicon esculentum Mill.) were cultured in vitro to evaluate the effects of sugar concentration, photosynthetic photon flux (PPF), CO2 concentration, ventilation rate of the vessel, and leaf removal on growth and photosynthesis. After 20 days of culture, the dry weights of plantlets derived from explants with leaves and cultured photoautotrophically (without sugar in the medium) under high PPF, high CO2 concentration, and high ventilation rate were more than twice as great as those of plantlets derived conventionally from explants without leaves and cultured photomixotrophically (with sugar in the medium) under low PPF, low CO2 concentration, and low ventilation rate (107 and 45 mg per plantlet, respectively). Under photomixotrophic micropropagation conditions, the dry weights of plantlets from explants with leaves increased more than did those of plantlets from explants without leaves. High PPF, high CO2 concentration, and high ventilation rate increased net photosynthetic rate and promoted growth of the plantlets under photomixotrophic micropropagation conditions. Photomixotrophic conditions produced the greatest dry weight and the longest shoots, but photoautotrophic conditions produced the highest net photosynthetic rate. The number of leaves did not differ significantly between photoautotrophically and photomixotrophically cultured plantlets. Thus, photoautotrophic micropropagation is applicable to the production of high quality tomato transplants.

scholarly journals Growth and Net Photosynthetic Rate of Solanun tuberosum in Vitro under Forced and Natural Ventilation

HortScience ◽  
1992 ◽  
Vol 27 (12) ◽  
pp. 1312-1314 ◽  
Author(s):  
Chieri Kubota ◽  
Toyoki Kozai
Keyword(s):  
Net Photosynthetic Rate ◽  
Photosynthetic Rate ◽  
Natural Ventilation ◽  
Dry Weight ◽  
Photon Flux ◽  
Fresh Weight ◽  
Photosynthetic Photon Flux ◽  
Photoautotrophic Micropropagation ◽  
Plantlet In Vitro

Growth and net photosynthetic rate of potato (Solanum tuberosum L.) `Benimaru' plantlet in vitro were studied under a conventional photomixotrophic condition [with 20 g sucrose/liter in the medium and under 70 μmol·m-2·s-1 photosynthetic photon flux (PPF)] with minimal ventilation (MV) and under photoautotrophic conditions (without sugar in the medium and under 190 μmol·m-2·s-l PPF) with enhanced natural ventilation using an air diffusive filter (DV) or with forced ventilation (FV). Fresh weight of the plantlets cultured in the FV and DV treatments was 2.4 times that of the plantlets cultured in the MV treatment. Net photosynthetic rate and dry weight per plantlet were the highest in FV followed by DV. For photoautotrophic micropropagation, FV was superior to DV.

Follicle-stimulating hormone-dependent estrogen secretion by rat Sertoli cells in vitro: Modulation by calcium

1991 ◽  
Vol 125 (3) ◽  
pp. 280-285 ◽  
Author(s):  
J. Alan Talbot ◽  
Ann Lambert ◽  
Robert Mitchell ◽  
Marek Grabinski ◽  
David C. Anderson ◽  
...  
Keyword(s):  
Sertoli Cells ◽  
Culture Medium ◽  
Follicle Stimulating Hormone ◽  
Dibutyryl Camp ◽  
Immature Rat ◽  
Estradiol Secretion ◽  
Old Rats ◽  
Stimulating Hormone

Abstract We have investigated the role of Ca2+ in the control of FSH-induced estradiol secretion by Sertoli cells isolated from 8-10 days old rats. Exogenous Ca2+ (4-8 mmol/1) inhibited FSH-stimulated E2 secretion such that, with 8 mmol/l Ca2+ and FSH (8 IU/l) E2 secretion decreased from 2091±322 to 1480±84 pmol/l (p<0.002), whilst chelation of Ca2+ in the culture medium with EGTA (3 mmol/l) increased E2 secretion from 360±45 to 1242±133 pmol/l) in the absence of FSH. Further, EGTA (3 mmol/l) markedly potentiated FSH (8 IU/l), forskolin (1 μmol/l) and dibutyryl cAMP (1 mmol/l)-stimulated E2 secretion. Addition of the Ca2+ ionophores, ionomycin (2-5 μmol/l) and A23187 (2 μmol/l), inhibited FSH (8 IU/l)-stimulated E2 secretion by >80%. The effect of ionomycin was totally reversible, whereas that of A23187 was irreversible. Ionomycin (5 μmol/l) had no effect on EGTA-induced E2 secretion in the absence of FSH, but reduced EGTA-provoked E2 secretion by 59% in the presence of FSH (8 IU/l). Similarly, forskolin- and dibutyryl cAMP-provoked E2 production was inhibited 46-50% by ionomycin (5 μmol/l). We conclude that FSH-induced E2 secretion from immature rat Sertoli cells is modulated by intra- and extracellular Ca2+.

Pulsatile GnRH secretion from primary cultures of sheep olfactory placode explants

Reproduction ◽  
2000 ◽  
pp. 391-396 ◽  
Author(s):  
AH Duittoz ◽  
M Batailler
Keyword(s):  
Culture Medium ◽  
Primary Cultures ◽  
Pulsatile Secretion ◽  
Olfactory Placode ◽  
Gnrh Secretion ◽  
Individual Culture ◽  
Pulsatile Gnrh

The aim of this study was to investigate the development of pulsatile GnRH secretion by GnRH neurones in primary cultures of olfactory placodes from ovine embryos. Culture medium was collected every 10 min for 8 h to detect pulsatile secretion. In the first experiment, pulsatile secretion was studied in two different sets of cultures after 17 and 24 days in vitro. In the second experiment, a set of cultures was tested after 10, 17 and 24 days in vitro to investigate the development of pulsatile GnRH secretion in each individual culture. This study demonstrated that (i) primary cultures of GnRH neurones from olfactory explants secreted GnRH in a pulsatile manner and that the frequency and mean interpulse duration were similar to those reported in castrated ewes, and (ii) pulsatile secretion was not present at the beginning of the culture but was observed between 17 and 24 days in vitro, indicating the maturation of individual neurones and the development of their synchronization.

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