• Fisheries and Aquatic Sciences
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• v.3 no.2
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• pp.151-155
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• 2000

Phaeodactylum tricornutum (Bacillariophyceae) is a marine diatom which has been supplied as a food of bivalves. In this study, growth responses of P. tricornutum to some nitrogen sources and sodium were investigated by measuring cell number and contents of chlorophyll a in culture. In medium with nitrogen and sodium, brisk cell division occurred and maximum growth rate was respectively found in the medium with 150 mg/l of nitrate and 10 mg/l of ammonium and urea. At 10-500 mg/l ammonium and urea and 200-500 mg/l nitrate, specific growth rate decreased slightly. However, no cell division observed in sodium-deficient medium, regardless of presence or absence of nitrogen. This suggests that sodium is required for the nitrogen uptake of P. tricornutum, resulting nitrogen uptake leading to cell division. Also the upper limits of ammonium and nitrate for the growth of P. tricornutum seem to be 10 mg/l and 500 mg/l, respectively.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1122-1126
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• 2009

The exogenously added cadaverine is effective in protecting Vibrio vulnificus from methyl viologen (MV)-induced superoxide stress at pH 8.5. Such a protective effect by cadaverine was not observed at pH 7.5. Consistently, the accumulated level of intracellular cadaverine at pH 8.5 is approximately four times as much as that of the control cell at pH 7.5. Cadaverine accumulation is not affected by MV. The protection of V. vulnificus by cadaverine from superoxide stress was abolished when cadB coding for the lysine-cadaverine antiporter was interrupted. However, the cadaverine-mediated protection was complemented with cadB DNA. Therefore, CadB of V. vulnificus not only acts as a lysine-cadaverine antiporter at acid pH to neutralize the external medium, but also mediates cadaverine uptake at alkaline pH to result in cell protection from superoxide stress.

• Journal of Chest Surgery
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• v.9 no.1
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• pp.20-26
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• 1976

Author has performed experimental study on hemodynamic changes of lung following radical hilar stripping and contralateral pulmonary artery ligation. In view of hemodynamic changes in group 1 (right pulmonary artery ligation only) and group 2(left hilar stripping+right pulmonary artery ligation). group 2 showed remarkable decrease rate in oxygen uptake (P<0.001) and total pulmonary blood flow(P<0.001), and the more increase rate in mean pulmonary artery pressure(P<0.02) and total pulmonary vascular resistance (P<0.001). Meanwhile, the decrease percent of left lung vascular resistance was lower than group 1(P<0.001). The hemodynamic changes in group 1 returned to control range two weeks later. In the group 2, two dogs were expired as a result of atelectasis and pulmonary hypertension. Among allying 8 dogs, five months after operation, follow up studies performed in two dogs, which showed normal pulmonary hemodynamics similar to preoperative data. The altered blood gas values and decreased oxygen uptake are more remarkable in denervated lung, which may due to pulmonary hypertension and partly retained more secretion in bronchial trees than usual. Important factors of raising pulmonary vascular resistance and pulmonary artery pressure are considered as the increased blood flow to remaining left lung and dysfunction of pulmonary vascular bed to accept the increased blood flow after denervation. Loss of nerve innervation had a influence, to some extent, to the decrease of oxygen uptake and the increase of pulmonary vascular resistance and pulmonary artery pressure. There can be little question that denervation does impair the pulmonary hemodynamics, however, intact pulmonary nerve innervation is not absolutely essential for survival of the animal.

• Journal of Korean Society of Forest Science
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• v.37 no.1
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• pp.35-40
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• 1978

The uptake ratio of supplying $P^{32}$ labelled double superphosphate and the hastening efficiency of the uptake by addition of magnesium sulfate to the fertilizer were studied on the ${\times}Populus $ albaglandulosa planted with 0/1 cutting in 1975. The results are summerized as follows. 1. Average 13% of supplying double superphosphate was absorbed into ${\times}Populus$ albaglandulosa planted on the reddish heavy clay soil in Institute of Forest Genetics. 2. The accumulation of absorbed magnesium was more amount in leaf than in stem. 3. The uptake ratio of supplying double superphosphate was able to increase up to 16%~33% by the addition of magnesium sulfate to the fertilizer. 4. It might be possible to increase the tree growth following the acceleration of photosynthesis due to the increasing amount of magnesium known to be a component of chlorophyll in leaf as well as to hasten the efficiency of uptake of phosphorus by the addition of magnesium to double superphosphate.

• Korean Journal of Environment and Ecology
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• v.27 no.5
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• pp.571-578
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• 2013

This study generated regression models through a direct harvesting method to estimate carbon storage and uptake by Pinus densiflora and Pinus koraiensis, the major evergreen tree species in urban landscape, and established essential information to quantify carbon reduction by urban trees. Open-grown landscape tree individuals for each species were sampled reflecting various diameter sizes at a given interval. The study measured biomass for each part including the roots of sample trees to compute the total carbon storage per tree. Annual carbon uptake per tree was quantified by analyzing radial growth rates of stem samples at breast height. The study then derived a regression model easily applicable in estimating carbon storage and uptake per tree for the two species by using diameter at breast height (DBH) as an independent variable. All the regression models showed high fitness with $r^2$ values of higher than 0.98. While carbon storage and uptake by young trees tended to be greater for P. densiflora than for P. koraiensis in the same diameter sizes, those by mature trees with DBH sizes of larger than 20 cm showed results to the contrary due to a difference in growth rates. A tree of P. densiflora and P. koraiensis with DBH of 25 cm stored 115.6 kg and 130.0 kg of carbon, respectively, and annually sequestered 9.4 kg and 14.6 kg. The study has broken new grounds to overcome limitations of the past studies which quantified carbon reduction of the study species by substituting, due to a difficulty in direct cutting and root digging of landscape trees, coefficients from forest trees such as biomass expansion factors, ratios of below ground/above ground biomass, and diameter growth rates.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.413-418
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• 1985

Tobacco plant(8-leaf seedlings) were grown on water culture fertilized with different N sources ($NO_3-N$, $NH_4-N$, $NO_3+NH_4-N$) during 15 days. Daily uptake of nutrients and inorganic constituents in plants were investigated in relation to growth responses of them. 1. Nitrate-fed plant showed higher daily uptake of inorganic cations than those in other treatments, and reached about two times higher uptake of nitrogen and three times more uptake of cations (K, Ca, Mg). Potassium was preferentially uptaken at a very fast rate from the beginning after treatment. Also $NO_3-N$ tended to be taken up selectively by the plant from the mixture of nitrate and $NH_4-N$. 2. The initial pH (pH 6.0) of culture medium drastically changed into acid (pH 4.0) in the $NH_4-N$ medium, but into slightly higher (pH 6.4) in the nitrate when measured after exposure of 24 hours. The mixture also tended to show an acidity but much weaker than $NH_4-N$ solution. 3. Nitrate-fed plant had a normal growth pattern but $NH_4-N$ fed plant almost stopped growing. Those plants containing both nitrate and ammonium N were also showed very poor growth.

• Korean Journal of Microbiology
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• v.13 no.2
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• pp.45-50
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• 1975

Uptake of $^{14}C$-sorbose and $^{14}C$-3-O-methylglucose by ungerminated conidia of Neurospora crassa was measured by means of the millipore filter technique. Initial rates of jptake of both sorbose and 3-O-methylglucose show a marked dependence optimal pH for uptake of both sugars is close to 4.75. When ungerminated conidia are "starved" with buffer for a prolonged period of time prior to assaying their transport capacity and mycelia, no de-repression of the glucose-repressible sugar transport system is effectuated in contrast to the findings for germinated conidia.d conidia.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.6
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• pp.557-564
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• 2009

Purpose: To evaluate the relationship between F-18 FDG uptake of tumor in PET/CT scan and pathological or immunohistochemial parameters of colorectal cancer. Materials and Methods: 147 colorectal cancer patients who underwent both pre-operative F-18 FDG PET/CT scan and surgery were included. In cases with perceptible FDG uptake in primary tumor, the maximum standardized uptake value (SUVmax) was calculated. The pathologic results such as site, size, depth of invasion (T stage), growth pattern, differentiation of primary tumor, lymph node metastasis and Dukes-Astler & Coller stage and immunohistochemical markers such as expression of EGFR, MLH1, MSH2 and Ki-67 index were reviewed. Results: 146 out of 147 PET/CT scans with colorectal cancer showed perceptible focal FDG uptake. SUVmax showed mild positive linear correlation with size of primary tumor (r=0.277, p=0.001) and Ki-67 index (r=0.226, p=0.019). No significant difference in F-18 FDG uptake was found according to site, depth of invasion (T stage), growth pattern, differentiation of primary tumor, presence of lymph node metastasis, Dukes-Astler & Coller stage and expression of EGFR. Conclusion: The degree of F-18 FDG uptake in colorectal cancer was associated with the size and the degree of Ki-67 index of primary tumor. It could be thought that FDG uptake of primary tumor has a correlation with macroscopic and microscopic tumor growth.

• Journal of Applied Biological Chemistry
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• v.54 no.4
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• pp.252-257
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• 2011

To remove excess nitrate from the agricultural environments, Enterobacter amnigenus GG0461 has been isolated as a bacterial strain having high capability of nitrate uptake activity. This strain was able to remove nitrate more than 3,000 ppm (50 mM) in the Pseudomonas agar F (PAF) medium. Therefore, it could be a candidate strain for a nitrate scavenger in the various contaminated environments, such as agricultural soils, livestock sewage, and industrial wastewater. In order to develop medium for the large-scale production of the strain GG0461, each component of PAF medium was replaced with the corresponding commercial product and the optimal conditions for bacterial growth and nitrate uptake activity were measured. Glycerol was replaced with the commercially available product and the nitrogen source was substituted with commercial tryptone, yeast extract, soybean meal, and fermented fish extract. Bacterial growth and nitrate uptake activity were maximal in the media containing 2% tryptone, followed by yeast extract, soybean meal, and fermented fish extract. The pH of the growth medium containing 2% tryptone was decreased by the bacterial nitrate uptake, suggesting that the nitrate uptake is mediated by a nitrate/proton antiporter. This result shows that the medium containing commercial tryptone was good enough for the physiological activity of the strain GG0461. Each component of PAF medium was successfully replaced with the corresponding commercial product except peptone. In conclusion, the composition of medium for the cultivation of the strain GG0461 was determined as 2% tryptone, 1% glycerol, plus required salts according to the composition of PAF medium.

• Journal of Gastric Cancer
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• v.20 no.1
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• pp.60-71
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• 2020

Purpose: The utility of 18-fluordesoxyglucose positron emission tomography ([¹⁸F]-FDG-PET) combined with computer tomography or magnetic resonance imaging (MRI) in gastric cancer remains controversial and a rationale for patient selection is desired. This study aims to establish a preclinical patient-derived xenograft (PDX) based [¹⁸F]-FDG-PET/MRI protocol for gastric cancer and compare different PDX models regarding tumor growth and FDG uptake. Materials and Methods: Female BALB/c nu/nu mice were implanted orthotopically and subcutaneously with gastric cancer PDX. [¹⁸F]-FDG-PET/MRI scanning protocol evaluation included different tumor sizes, FDG doses, scanning intervals, and organ-specific uptake. FDG avidity of similar PDX cases were compared between ortho- and heterotopic tumor implantation methods. Microscopic and immunohistochemical investigations were performed to confirm tumor growth and correlate the glycolysis markers glucose transporter 1 (GLUT1) and hexokinase 2 (HK2) with FDG uptake. Results: Organ-specific uptake analysis showed specific FDG avidity of the tumor tissue. Standard scanning protocol was determined to include 150 μCi FDG injection dose and scanning after one hour. Comparison of heterotopic and orthotopic implanted mice revealed a long growth interval for orthotopic models with a high uptake in similar PDX tissues. The H-score of GLUT1 and HK2 expression in tumor cells correlated with the measured maximal standardized uptake value values (GLUT1: Pearson r=0.743, P=0.009; HK2: Pearson r=0.605, P=0.049). Conclusions: This preclinical gastric cancer PDX based [¹⁸F]-FDG-PET/MRI protocol reveals tumor specific FDG uptake and shows correlation to glucose metabolic proteins. Our findings provide a PET/MRI PDX model that can be applicable for translational gastric cancer research.