In Vivo Fluorescence Excitation Spectra of Hematoporphyrin-Derivative (HpD)

Gijsbers, G. H. M.; Gemert, Martin J. C. van; Breederveld, D.; Langelaar, J.; Boon, Tom A.

doi:10.1007/978-1-4684-4721-7_36

Cited by 21 publications

(17 citation statements)

References 3 publications

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“…Our value of 5.2cm-t for a for tumour at 630 nm is close to the value of 6.3 cm-1 found for a human lung carcinoma by Svaasand et al (1981). Further, measurements (not presented here) on a rat urothelial tumour used previously (Gijsbers et al, 1984) yielded results very similar to those of Table I. The data in Table I Figure 1 shows that there is a more or less linear relation between depth of necrosis and the logarithm of the light dose.…”

Section: Photophysical Parameterssupporting

confidence: 89%

Wavelength and light-dose dependence in tumour phototheraphy with haematoporphyrin derivative

Gemert¹,

Berenbaum²,

Gijsbers³

1985

Br J Cancer

101

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Summary Red light (c. 630 nm) is almost universally used in tumour phototherapy as it is the most penetrating of the porphyrin excitation wavebands. However, measurements of tumour attenuation of light of different wavelengths and of the excitation spectrum of haematoporphyrin derivative in vitro suggested that green light might be more efficient than red in destroying thin tumours. Experimentally, we confirmed this for tumours up to -1.2mm thick, a depth exceeding that of most carcinomas-in-situ. The superiority of green light over red in terms of the illumination time required to produce equivalent depths of necrosis may extend to greater depths (3-4 mm) if the former is produced by an argon laser and the latter by an argon-pumped dye laser.The relation between depth of necrosis zn and light dose D is shown to be zn=a x 'n(D/lA) where 0A iS the attenuation coefficient for light at wavelength A and 0A the threshold light dose for producing necrosis at that wavelength. This logarithmic relationship suggests that it may be difficult to eradicate large tumours merely by increasing the light dose, and indicates the need for other approaches.

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Section: Photophysical Parameterssupporting

confidence: 89%

Wavelength and light-dose dependence in tumour phototheraphy with haematoporphyrin derivative

Gemert¹,

Berenbaum²,

Gijsbers³

1985

Br J Cancer

101

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“…Knowledge of the in vivo absorption spectrum of photosensitizers used for PDT is important so that the right wavelength of the treatment light is chosen. 4 Even though the shift is rather small, it should be noted that clinical protocols usually prescribe a treatment wavelength of 630 Ϯ 3 nm. Thus 633 nm would in principle be acceptable, but because of the relatively narrow peak of the in vivo action spectrum of HpD 2 , the treatment effect would be considerably reduced.…”

Section: Discussionmentioning

confidence: 99%

“…Several researchers have demonstrated that, for a hematoporphyrin derivative (HpD) and PHOTOFRIN, the absorption spectrum, 1 the action spectrum, 2,3 and the fluorescence excitation spectrum 4 all have a maximum at 625 nm in vivo, as compared with 630 nm for the action spectrum in vitro. 5 To optimize the PDT efficacy, one would like to know the action spectrum of the photosensitizer in situ.…”

Section: Introductionmentioning

confidence: 99%

In vivo absorption spectroscopy of tumor sensitizers with femtosecond white light

et al. 2005

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“…Investigation of the luminescent properties of these salts is rather critical for advancing medical diagnostics. This method together with known biochemical methods can be applied to rapid diagnosis without using chemical preparations [1][2][3][4][5].…”

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confidence: 99%

Thermally stimulated luminescence of urine salts

Bordun

Drobchak

2007

J Appl Spectrosc

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We investigated thermally stimulated luminescence (TSL) of urine salts in the normal state and with oxalate, urate, and phosphate salts. We found that the presence of pathological salts leads to a decrease of TSL intensity and to the appearance of additional TLS bands with maxima at 118 and 205 K in addition to the characteristic bands at 173 and 260 K. The TLS bands are related to the urine components. The TSL intensities of urine salts of different chemical composition are compared. The thermal activation energy of the strongest TSL bands is determined.Introduction. Investigations of water-salt exchange by body fluids are important in modern research on the physiology of living organisms and deviations from normal functioning of organs. The problem of water-salt exchange is important theoretically and for therapy of kidney and other diseases arising as a result of disruptions of this type of exchange processes in the organism.Kidneys are the main organs that provide constant physical chemical characteristics for a living organism. The product of their activity, urine, can provide diagnostic information about the organism. Disruptions of exchange lead to the appearance in urine of salts that it does not normally contain. These salts can be indicative of various diseases. Salts that correspond to the development of kidney stones, for example, oxalates [Me 2 (COO) 2 ], urates [MeC 5 H 3 O 3 N 4 ], phosphates [Me 3 PO 4 ], and others are especially significant. Investigation of the luminescent properties of these salts is rather critical for advancing medical diagnostics. This method together with known biochemical methods can be applied to rapid diagnosis without using chemical preparations [1][2][3][4][5].Experimental. Urine samples obtained from the clinical laboratory of Lvov Regional Specialized Clinical Hospital were investigated. Samples were analyzed biochemically beforehand. We used urine (2-3 drops) placed on a quartz plate and heated to 40-50 o C. Dry solids after evaporation of the liquid were investigated. All samples were prepared under identical conditions. Samples for TSL studies were placed in a vacuum cryostat where the temperature was varied in the range 80-400 K. Radiation from a URS-55 x-ray generator (40 kV, 10 mA, Russia) with a copper anode at 80 K was used. The exposure (D) was measured with an IDMD-1 dosimeter. The total TSL emission intensity was recorded with a FÉU-551 photomultiplier (Russia) with an electrical amplifier, the output signal of which was fed to a PDA-1 potentiometer (Ukraine).Results and Discussion. Figure 1a-d shows TSL curves (total luminescence intensity as a function of temperature) for normal urine salts and those with pathological salts. It can be seen that two characteristic TSL bands with maxima at 173 and 260 K are identified in the studied temperature range regardless of the presence of pathological salts. The band with a maximum at 173 K dominates all samples. Furthermore, the presence of pathological salts leads to the appearance of two additional TSL bands wi...

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In Vivo Fluorescence Excitation Spectra of Hematoporphyrin-Derivative (HpD)

Cited by 21 publications

References 3 publications

Wavelength and light-dose dependence in tumour phototheraphy with haematoporphyrin derivative

Wavelength and light-dose dependence in tumour phototheraphy with haematoporphyrin derivative

In vivo absorption spectroscopy of tumor sensitizers with femtosecond white light

Thermally stimulated luminescence of urine salts

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