摘要:

Abstract—Reflectance spectrophotometry from 400 to 800 nm on different cutaneous pigmented lesions, including primary and metastatic malignant melanoma, pigmented nevi, lentigo and seborrhoeic keratosis, has been performed by using an external integrating sphere coupled to a spectrophotometer. Measurements show that reflectance spectra of the different lesions manifest dissimilar patterns, particularly in the near IR region. Comparison of reflectance of nevi with that of malignant melanomas results in a highly significant difference (P<10‐6) between the two samples. Though interpretation of the specta remains difficult as a result of the complexity of the optical processes of scattering and absorption, our results suggest that a detailed analysis of the reflectance spectrum may give clinically useful information, and could be utilized as an aid in clinical diagnosis of cutaneous pigmented lesions, especially where malignant melanoma is concer

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08470.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—This paper reports on the role of endogenous and exogenous thiols in the merocyanine 540 (MC 540)‐sensitized photoirradiation of L1210 leukemia cells, human erythrocytes, and humanHerpes simplexvirus type 1. Several measures taken to decrease the intracellular content of glutathione enhanced the cells sensitivity to MC 540‐sensitized photoirradiation while stimulation of glutathione biosynthesis or supplementation of the extracellular or extraviral thiol content decreased the photosensitivity of cells and viruses. Taken together, these data suggest that endogenous and exogenous thiols can modulate the sensitivity of cells and enveloped viruses to MC 540‐sensitized photoirradiation. They also pose new questions as to the mechanism of MC 540‐sensitized p

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08471.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—Time resolved measurements of singlet oxygen phosphorescence at 1270 nm were made from unsealed red cell ghosts, labeled with 5‐(N‐hexadecanoyl)aminoeosin and suspended in deuterium oxide buffer. The singlet oxygen emission lifetime was long, 23 ± 1 μs. The lifetime of the singlet oxygen phosphorescence from intact unsealed ghosts was not a measure of the singlet oxygen lifetime within the red cell ghost membrane, however. The prolonged singlet oxygen emission was due to singlet oxygen escaping from the thin membrane into the buffer, since the emission lifetime was significantly shortened by adding azide ion or water to the deuterium oxide buffer.The lifetime of singlet oxygen within the red cell ghosts membrane was estimated by dispersing the ghosts with detergent and then measuring the singlet oxygen lifetime in deuterium oxide buffers containing various dilutions of the dispersed ghosts. Apparent singlet‐oxygen quenching constants were measured using four different photosensitizing dyes and two different detergents. The apparent quenching constant was independent of the dye used, but varied significantly with different detergents. Extrapolation of this data to “100%” ghost concentration gave a singlet oxygen lifetime from 24 and 130 ns. A ghost concentration of “100%” was defined as that concentration of red cell ghost molecules which would be contained within a red cell ghost membrane pellet containing no buffer solutions. Most of the singlet oxygen quenching was due to proteins. Lipids extracted from red cell ghosts accounted for only 2‐7% of the total singl

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08472.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—The photodynamic inactivation of HSV‐1, a virus having a membranous envelope, with both a decaalkyl sapphyrin and its dicarboxy‐substituted analog was studied. The decaalkyl sapphyrin was as efficient in the inactivation of HSV‐1 on a per macrocycle basis as DHE, whereas the efficiency of the dicarboxy‐substituted sapphyrin was approximately two orders of magnitude less. Fluorescence studies of sapphyrin's binding to liposomes and VSV suggested that the decaalkylsapphyrin bound monomerically to cholesterol‐rich regions of the viral envelope, whereas its charged analog localized in a more polar

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08473.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—Chronic exposure of hairless mice to ultraviolet light (UVB 290‐320 nm) causes degradative changes in the dermal matrix and wrinkle production. We compared the effects of two different UVB dosing regimens on wrinkle production and dermal damage in female Skh:HR‐1 hairless mice using a bank of unfiltered FS‐40 lamps. One group of mice, the low dose group, was exposed to a suberythemal UVB dose of 12 mJ/cm2(1 MED = 14 mJ/cm2), 3 times per week for 20 weeks (total dose = 0.72 J/cm2). A second group, the high dose group, was exposed also 3 times per week for 15 weeks to a UVB dose which started with the sub‐erythemal dose of 12 mJ/cm3at Week 1. and J MED at week 2. The dose was then increased weekly by 1 MED until reaching 4 MED at week 5. The animals were then dosed at 4 MED for 10 additional weeks (total dose = 2.1 J/cm2). Visual results indicate that, as expected, within the same group, the degree of wrinkling was generally dependent on the total UVB dose administered. However, comparison between the low dose and high dose groups shows that equal cumulative UVB doses did not always result in identical wrinkle grades. For example. at a cumulative dose of 0.5 J/cm2, the mean wrinkle grade for the low dose group was 1.75 compared to that of 1.2 for the high dose group (age‐matched = 0). This observation may suggest that there are other factors in addition to total cumulative dose which are important for the appearance of wrinkling in

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08474.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—The pharmacokinetics of Zn phthalocyanine (ZnPc) encapsulated in dipalmitoyl‐phosphatidyl‐choline (DPPC) liposomes, injected intravenously in Skh:HR‐1 nude mice, was monitored by twoin vitrotechniques and onein vivotechnique, all based on fluorescence spectroscopy. Thein vitromethods involve either fluorescence measurements on thin tissue sections or on extracts from these tissues. Thein vivomethod involves the fluorescence measurement at the skin surface. Bothin vitrotechniques gave similar results which are consistent with previous findings on the pharmacokinetic behavior of ZnPc. The liver and spleen showed rapid ZnPc concentration increases, reaching a maximum level in 30 min. or less post drug administration. Relatively little ZnPc was detected in the skin, fat or muscle, the maximum concentration occurring at 12h.In vivofluorescence reached a maximum intensity approx. 6 h post injection at the mid‐chest analysis site and at 12 h in the thigh. Thein vivomeasurements at two different anatomical sites showed pharmacokinetic behavior that reflects an overall integrated fluorescence originating from several tis

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08475.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—A series of tumor localizing porphyrins was evaluated with respect to their ability to elicit cutaneous photosensitivity and systemic immunosuppression, two of the most common side effects associated with photodynamic therapy. Using the murine ear swelling response as an indicator, it was found that all the non‐metalloporphyrins caused cutaneous photosensitization. Immunosuppressive effects were noted using hematoporphyrin derivative (HPD) andmeso‐tetra(4‐sulfonatophenyl)porphine if sensitization occurred immediately after photoirradiation, but none were evident using Photofrin II (PII) ormeso‐tetra(4‐carboxyphenyl)porphine (TCPP). Subsequent studies indicated that PII and TCPP manifested a delayed type immunosuppression similar to that found following UVB photoirradiation. Manganese (III)meso‐tetra(4‐sulfonatophenyl)porphine, a prototype magnetic resonance imaging contrast agent, was also evaluated because of its reported demetallationin vivo. It was found to cause neither cutaneous photosensitivity nor im

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08476.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—Monoacyl hydrazides based on 5‐methyldehydroluciferin and simpler analogs have been synthesized; they proved to be chemiluminescent on treatment with a strong base in DMSO in the presence of oxygen. The light emitters in these cases appear to be the corresponding carboxylate ions; a pathway involving an oxidative decarboxylation was eliminated as a possibility by consideration of the fluorescence wavelengths of the corresponding oxyluciferins. A reaction mechanism for the luminescence involving the possible intermediacy of an azadioxetane is proposed. The corresponding amides were also synthesized; they proved to be equally chemiluminescent to the hydrazides in the dehydroluciferin ser

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08477.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—The 5‐methyl analog of firefly oxyluciferin, two isomeric O‐methyl ether derivatives of it and anO, OÓ‐dimethyl ether derivative were synthesized and their UV absorption and fluorescence emission spectra were determined. Comparisons of the emission data with the emission wavelength in bioluminescence indicate that the mono‐anions of firefly oxyluciferin are candidates for the light‐emitters in bioluminescence. Further, we have found that the chemiluminescence of active esters of firefly luciferin produces (from the keto form of oxyluciferin) only red light emission under a variety of conditions; a yellow‐green light emission (from the enolic forms of the oxyluciferin product) could n

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08478.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract—Biophoton emission (ultraweak photoemission) is observable in isolated spinach chloroplasts, even after several hours of dark adaptation. This spontaneous light emission is oxygen dependent, decreased by respiratory inhibitors such as cyanide or salycilhydroxamic acid, suppressed byp‐benzoquinone and enhanced by NADPH. We suggest that the respiratory chain of chloroplasts is involved in theseries of redox reactionsleading to the dark excitation of the emitter of biophotons, presumably chlorophyll molecules.Biophoton emission is inhibited by superoxide dismutase, implying that the univalent reduction of molecular oxygen is associated with this process, in a yet unknown

ISSN:0031-8655    

DOI:10.1111/j.1751-1097.1991.tb08479.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY