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Intracellular localization of sulfonated meso-tetraphenylporphines in a human carcinoma cell line 总被引:3,自引:0,他引:3
The intracellular localization of meso-tetraphenylporphines sulfonated to different degrees (TPPSn), in a human cervix carcinoma cell line (NHIK 3025), was studied by fluorescence microscopy and fluorescence spectroscopy. After an 18 h incubation, TPPS4, TPPS2a and TPPS2o were localized in extranuclear granules. Studies of cells stained with both TPPS4, and acridine orange, which is known to fluoresce red in lysosomes, indicated that these granules were lysosomes. In addition, a fraction of the cellbound TPPS4, TPPS2a and TPPS2o seems to be associated with the plasma membrane. Fluorescence quenching studies of cells doublestained with acridine orange and TPPS4 indicated that TPPS4 is also localized in the nucleus and in the extralysosomal cytoplasm. The intracellular location of TPPS1 differed from that of the other TPPSns studied: In 6 out of 9 experiments fluorescing extranuclear granules were found. A diffuse fluorescence extending from the perinuclear area was also observed. 相似文献
13.
Based on an analysis of second-order hydrodynamic forces induced by coupling of first-order wave potentials, second-order hydroelastic equations are established and solved in the frequency domain. The responses of a very large floating structure in multidirectional irregular waves are studied. The characteristics of the difference and sum frequency coordinates are discussed in detail; peaks can be found at the difference and sum frequencies close to the wet resonant frequencies of each mode. We present and analyze the maximum vertical displacement of different points as well as the time history of the vertical displacements of selected points. The differences of the combined (the summation of the linear and non-linear responses) and linear displacements of the selected points are calculated. Our results demonstrate that non-linear fluid forces influence the total responses of the referenced floating structure. 相似文献
14.
Frozen solutions of H2SO4 and acid 7 M NaClO4 containing Fe2+ ions have been exposed to X rays and UV light and examined by EPR methods. It is concluded that the H atoms formed in UV-irradiated acid perchlorate matrices do not have mobile electrons as precursors. Thus no trapped electrons are found after UV irradiation even though these matrices provide efficient traps for electrons. The effect of the electron scavenger NO?3 is identical in UV- and X-irradiated matrices and largest in the H2SO4 matrix. Thus it seems that NO?3 acts on a similar H-atom precursor in the two cases, and that this precursor may be an excited CTTS state, rather than a mobile electron. The absence of allyl alcohol scavening effect on H atoms produced by UV light in the perchlorate matrix indicates that this H-atom scavenger does not interact with the CTTS state, and that the H atom is trapped in the vicinity of the Fe2+ ion where it was formed. The presence of small amounts of Fe2+ ions (< 10?3 M) in the matrices causes a marked decrease in the spin—lattice relaxation time of the trapped hydrogen atoms as well as a decrease in the intensities of the satellite lines relative to the main hydrogen lines. 相似文献
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Leulescu Marian Pălărie Ion Moanţă Anca Cioateră Nicoleta Popescu Mariana Morîntale Emilian Văruţ Marius Ciprian Rotaru Petre 《Journal of Thermal Analysis and Calorimetry》2019,136(3):1249-1268
Journal of Thermal Analysis and Calorimetry - Thermal behavior of Brown HT food dye was studied in correlation with the physical and biological antioxidant properties. Brown HT’s structure... 相似文献
17.
Leulescu Marian Rotaru Andrei Pălărie Ion Moanţă Anca Cioateră Nicoleta Popescu Mariana Morîntale Emilian Bubulică Maria Viorica Florian Gabriel Hărăbor Ana Rotaru Petre 《Journal of Thermal Analysis and Calorimetry》2018,134(1):209-231
Journal of Thermal Analysis and Calorimetry - The food-colouring dye tartrazine is a significant additive and in the same time a biologically active material. Thermal behaviour of trisodium... 相似文献
18.
Johan Moan Kristian Berg Øystein B. Gadmar Vladimir Iani LiWei Ma Petras Juzenas 《Photochemistry and photobiology》1999,70(4):669-673
The formation of protoporphyrin IX (PpIX) in human skin during topical application of 5-aminolevulinic acid (ALA) was found to be strongly temperature dependent, with an activation energy of about 17 kcal/mol. This temperature dependence is mainly related to porphyrin production and not to ALA penetration into the skin. The penetration of ALA into mouse and human skin was almost temperature independent. The activation energy of PpIX production in mouse skin was practically identical with that in human skin. The activation energy of ALA uptake by cells in vitro was about 10 kcal/mol and that for PpIX production was about 13 kcal/mol. The latter activation energy was within the error limits similar to that for the activity of the enzyme porphobilinogen deaminase, suggesting that this enzyme might represent a rate-limiting step for PpIX production in living tissue. 相似文献
19.
Gelsor Norsang LiWei Ma Arne Dahlback Ciren Zhuoma Wangmo Tsoja Alina Porojnicu Zoya Lagunova Johan Moan 《Photochemistry and photobiology》2009,85(4):1028-1031
UVB from the sun and intake from food are the only human sources of vitamin D. Tibet is a unique region for comparisons of these sources: (1) it lies at a low latitude and at a high altitude and has very large annual fluences of UVB; (2) the traditional Tibetan food is poor in vitamin D. Blood samples were taken from 63 persons of different age, with different occupations and staying at different places. UVB doses at these places were measured. The samples were analyzed by a standard radioimmune assay for determination of the serum concentration of 25 hydroxyvitamin D (25(OH)D). The main finding was that among nomads, there seems to be severe vitamin D deficiency (serum levels of 25(OH)D < 30 n m ). We tentatively propose that the low level of 25(OH)D of nomads is related to their clothing and sun exposure habits. For persons of other occupations (students, teachers and farmers) the levels are higher, although a significant fraction of these persons also have lower levels than 75 n m , by many regarded as a limit for insufficiency related to a number of negative health conditions. The annual dose of vitamin D-generating UVB is about five times larger in Lhasa than in Oslo. Despite this, the average vitamin D status seems to be similar, except in the case of nomads. This phenomenon is certainly related to food habits. In conclusion, the 25(OH)D status among nomads in Tibet appears to be alarmingly low. However, for people of other occupations the status is more normal. 相似文献
20.
Mateusz Kwitniewski Asta Juzeniene Li-Wei Ma Renata Glosnicka Alfreda Graczyk Johan Moan 《Journal of photochemistry and photobiology. B, Biology》2009,94(3):214-222
Photodynamic therapy (PDT) is an alternative treatment modality involving light activated drugs, called photosensitizers (PSs), to treat cancer and non-cancerous conditions. The search for new compounds which might become effective PSs is the major direction for PDT development. In the present work we have studied the dark toxicity, intracellular localization and photodynamic properties of four potential, water soluble, second generation PSs – PP(Arg)2, PP(Ser)2Arg2, PP(Ala)2Arg2, PP(Phe)2Arg2, all diamino acid derivatives of protoporphyrin IX. Human prostate cancer (DU-145) and squamous carcinoma (A431) cells were used as experimental model.Among investigated compounds PP(Ser)2Arg2 exhibited the lowest dark toxicity and the highest PDT effectiveness towards both cell lines. Fluorescence microscopy revealed the time-dependent changes in intracellular localization of the PS which were related to the phototoxicity. The results show that PP(Ser)2Arg2 may be a potential PS for PDT. 相似文献