PHOTOBINDING OF CHLORPROMAZINE AND ITS SULFOXIDE IN VITRO AND IN VIVO

Abstract— Photosensitivity as observed after chlorpromazine (CPZ) treatment is enhanced in the UVA- rather than the UVB region, whereas CPZ has its absorption maximum at 305 nm. This long wavelength sensitivity has sometimes been ascribed to CPZ-sulfoxide (CPZSO) which has an absorption maximum at 340 nm. We compared the photobinding properties of CPZSO and CPZ under both in vitro and in vivo conditions.
With 310 and 370 nm lamps CPZSO absorbs twice as much light as CPZ but still binds less efficiently to HSA in vitro. At wavelengths longer than 380 nm CPZSO does not absorb nor photobind to HSA (420 nm lamps) in contrast to CPZ.
In vivo the bioavailability of CPZ and CPZSO in ears, eyes and skin of the back of Wistar rats is comparable, yet irradiation with 370 nm light caused more CPZ-photobinding in these tissues. Chlorpromazine binds relatively more compared to CPZSO, to constituents of deeper lying tissues (dermis). This corresponds with the observation that both the ratio of in vitro CPZ photobinding to CPZSO photobinding, and the penetrating ability of light in the skin increase with wavelength.
In the eyes, where the lens efficiently filters out light with wavelengths shorter than 370 nm, no CPZSO photobinding was observed, in contrast to CPZ; this also corresponds with the in vitro experiments. Therefore it seems more likely that the observed wavelength maximum in the photosensitivity action spectrum after CPZ treatment should be attributed to the non-sulfoxidated drug rather than to the sulfoxidated compound.     

A COMPARISON OF IN VIVO AND IN VITRO TESTING OF SUNSCREENING FORMULAS

Abstract— Seven commercially available sunscreens were compared by three different methods. Absorbance spectra were measured for each product in isopropanol solution and also on hairless mouse epidermis. In vivo tests were performed on human volunteers using a Xe arc solar simulator. Sun Protection Factors (SPF) were calculated by each method for each product tested and the results compared. By all methods used, the combination of 7% octyl dimethyl para-aminobenzoic acid and 3% oxybenzone provided the most protection from U.V. light. While estimates of the effectiveness of all products were much too high when calculated by the isopropanol solution method, the hairless mouse epidermis technique seems to be an accurate tool for predicting product efficacy in vivo .     

FLUENCE-RATE DEPENDENCE OF MONOPHOTONIC REACTIONS OF NUCLEIC ACIDS IN VITRO AND IN VIVO

The Bunsen-Roscoe law, also known as the reciprocity law ( E = f(F) with F = I t ) has only limited validity for monophotonic reactions of nucleic acids. Especially at low fluence rates, the extent of in vitro and in vivo photoreactions of nucleic acids in the far-UV and near-UV range is a function of the fluence and of the fluence rate ( E = f (F;I)). In vitro experiments with poly(dA)poly(dT) clearly show that the far-UV (254 nm) response, indicated by the changes of the ellipticity at 315 nm, does not obey the Bunsen-Roscoe law at low fluence rates in the range between 1 W m^-2 and 20 W m^-2. In vivo experiments with Escherichia coli revealed very similar anomalies. Studying the growth delay after irradiation with far-UV light at 280 nm or near-UV light at 334 nm, we have confirmed the lack of reciprocity in both spectral ranges. The failure of the Bunsen-Roscoe law for the 280 nm and 334 nm UV irradiation effect at low fluence rates was in the range O < I < 40 W m^-2. In both cases reciprocity occurred at higher fluence rates (40 < I < 100 W m^-2).     

PHOTOTOXICITY FROM BENOXAPROFEN: IN VIVO AND IN VITRO STUDIES

Abstract Benoxaprofen (2-[4-chlorophenyl]-α-methyl-5-benzoxazole acetic acid), a non-steroidal antiinflammatory drug, was found to provoke phototoxicity reactions in humans. Exposure of the skin of benoxaprofen-treated subjects to either solar simulating radiation or a broad UV-A wavelength band produced intense itching and burning sensations, followed by the development of a classical wheal and flare response within 2-4 min. Phototoxicity was related to both the UV radiation fluence and the dose of orally administered benoxaprofen. Wavelengths between 320 and 340nm were active in provoking urticaria. In vitro studies demonstrated that benoxaprofen and UV irradiation produced a dose-dependent lysis of sheep erythrocytes which did not appear to be dependent on the presence of oxygen. Red cells were not lysed by pre-irradiated benoxaprofen arguing against the production of stable lytic photoproducts. Human neutrophils were lysed by benoxaprofen and UV light which resulted in the liberation of both cytoplasmic and lysosomal enzymes. Benoxaprofen failed to induce photolysis of human platelets and photoactivation of complement in human serum. It is suggested that phototoxic urticaria provoked by benoxaprofen may be due to a direct photolytic effect on human dermal mast cells.     

KINETICS OF DNA-INDUCED BREAKS BY REDUCTONE TREATMENT: IN VITRO AND IN VIVO STUDIES

Abstract— Reductone, a keto-aldehyde that blocks repair of UV-induced DNA damage also produces DNA breaks. These breaks are observed either in irradiated or unirradiated wild type and uvrA strains of Escherichia coli. DNA breakage has also been observed after in vitro treatment of T4 phage DNA. The results suggest that the breaking ability of reductone is a result of a direct attack on DNA.     

THE EFFECT OF APPLIED THICKNESS ON SUNSCREEN PROTECTION: IN VIVO AND IN VITRO STUDIES

The effect of applied thickness of sunscreen on the degree of protection against ultraviolet exposure has been investigated using an in vitro model (excised human epidermis) and phototesting in human subjects. The agreement between the protection factors obtained by each technique was excellent. It is shown that the influence of applied thickness on sunscreen protection factors is much less than would be predicted by Beer's law.     

OPTICAL PROPERTIES OF PHYTOCHROME IN THE BLUE- SPECTRAL REGION AS MEASURED IN VIVO AND IN VITRO

In the blue spectral region, the phototransformation difference spectrum of oat phytochrome extracted as P_fr differs from that of phytochrome extracted as P_r. The difference absorbance maximum for phytochrome extracted as P_fr is at 420 nm, while that extracted as P_r is at 412 nm. The phototransformation difference spectrum measured in the blue in oat coleoptile tips without inner leaves, corresponds very well with that of phytochrome as extracted in its P_fr form. There is, however, a slight apparent attenuation of the blue difference band relative to those in the red-far-red. In coleoptile tissue containing inner leaves, the blue difference band is relatively even more highly attenuated. A similar attenuation is observed in the blue, in the protochlorophyllide to chlorophyllide phototransformation difference spectrum. In the spectrum measured with excised coleoptile without inner leaves, there is a small attenuation, while in coleptile tissue with inner leaves the attentuation is nearly 9-fold. These data suggest that the observed attenuation is probably artifactual. Neither instrumental non-linearity nor fluorescence induced by the measuring beam could explain the observed attenuation. It is suggested that the observed attenuation is probably mainly the result of wavelength dependent scatter amplification, the amplification in the blue being attenuated by the high background absorption of other pigments in this region.     

标准样品在光谱仪器分析中应用

针对光谱标准样品名称术语上存在的混乱现状,提出了作者的观点和建议。并对各类样品在光谱分析中的作用、相互关系、选用原则及在实际使用过程中应注意的事项等进行讨论。     

ACTION SPECTRA OF PHYTOCHROME IN VIVO*

Abstract— A method is described to determine spectral properties of phytochrome in vivo. For photochrome in 7-day-old dark-grown Cucurbita pepo L. seedlings the mole fraction of the far-red-absorbing form (P_fr) present at photoequilibrium at 664 nm was found to be 0.76 ± 0.02 in vivo. Based on reflectance measurements, the photon fluence rate just below the surface of the cotyledons was calculated. Local rates of photoconversion for known local fluence rates were measured across cotyledons after non-saturating irradiations with wavelengths between 544 and 781 nm and in situ molar photoconversion coefficients were obtained. In contrast to purified oat phytochrome, the in situ molar photoconversion coefficients for P_fr show a strong shoulder between 660 and 700 nm. The maximum of P_fr absorption is at 726 nm. An isosbestic point of phytochrome is found at 686 nm. The mole fraction of P_fr present at photoequilibrium with 686 nm light is 0.58. The ratio of photoconversion quantum yields (that for P_r→ P_fr divided by that for P_fr→ P_r) is 1.38 ± 0.06.     

ANALYTICAL MODELING FOR THE OPTICAL PROPERTIES OF THE SKIN WITH IN VITRO AND IN VIVO APPLICATIONS

Abstract— Analytical modeling that interrelates the optical properties of multilayered structures is applied to the skin. The mathematical approach is based on relations of diffuse reflectance and transmittance of a multilayered system and the diffuse reflectance and transmittance of each component layer. The formula can also be derived from the Kubelka–Munk theory of radiation transfer. Using both collimated and diffuse incident irradiance, the applicability of the model to human epidermis over the UV and visible region has been verified. The model has been applied to calculate the absorption and scattering coefficients of human epidermis in vitro , and to estimate the epidermal transmittance under simulated in vivo condition.     

氯柱硼镁石的硼酸溶液中硼氧配阴离子的FT-IR光谱分析

硼有ＢＯ3平面三角形和ＢＯ4四面体两种配位类型 ,在晶体和水溶液中硼以聚合硼氧配阴离子形式存在。硼氧配阴离子存在形式及其相互作用受溶液温度、ｐＨ值、总硼浓度及金属阳离子存在等多种因素的影响。可见 ,硼酸盐水溶液要比一般盐水溶液复杂。振动光谱能有效地用于鉴定和表征固体硼酸盐 ,至今对水溶液硼酸盐结构的研究却较少。由于多数硼酸盐在室温水中的溶解度较小 ,溶液中硼浓度低 ,加之溶剂水对ＩＲ辐射具有明显吸收作用 ,致使硼酸盐水溶液红外光谱中多聚硼氧配阴离子特征峰被减弱、模糊甚至被湮灭。近年来 ,Ｊ .Ｍａｘ[1 ] 等在对盐…     

FLUORESCENCE AND LUMINESCENCE STUDIES OF IN VIVO CHLOROPHYLL WITH A LASER PHOSPHOROSCOPE*

Abstract— A simple apparatus using a He-Ne laser and a rotating sector gives repetitive light pulses with rise and fall times of a few μsec and intensities of up to 0.65 W/cm². Fluorescence during the actinic pulse and luminescence following it (after 20 μsec) may be recorded and compared. Sampling of the suspension of photosynthetic cells or chloroplasts by intermittent flow permits the averaging of 25 such measurements. With Chlorella, the fast (30 μsec) and the medium (30 msec) components of luminescence do not saturate at the same light intensity. The former saturates in the same range as the photochemical fluorescence rise, whereas the latter saturates at higher intensities. Under a variety of conditions, the decay of luminescence intensity is always strongly polyphasic. Analysis of the kinetics discloses a dependency with the log concentration of the hypothetical precursor, suggesting a connection of luminescence with electrochemical phenomena. The shape of the luminescence integral, as well as the light saturation pattern, suggests another kind of interpretation, in terms of several pools, possibly two of equal size. In the presence of hydroxylamine, only one pool is seen. The stimulating effect of preillumination is only observed for the medium component. However, a stimulation of short duration also exists for the fast component. The problems of number of pools, mechanism, and stimulation are briefly discussed.     

SPECTROSCOPIC AND PHOTOACOUSTIC STUDIES OF HYPERICIN EMBEDDED IN LIPOSOMES AS A PHOTORECEPTOR MODEL*

Abstract— In photoresponsive ciliates, like Blepharisma japonicum and Stentor coeruleus, the photoreceptor pigments responsible for photomotile reactions are hypericin-type chromophores packed in highly osmiophilic subpellicular granules. Liposomes loaded with hypericin can constitute a simple model system, appropriate for understanding the primary light-induced molecular events triggering the sensory chain in these microorganisms. Optical absorption, steady-state and time-resolved fluorescence and pulsed photoacoustic calorimetry have been used to measure spectral distributions, fluorescence lifetimes, radiative and radiationless transition quantum yields of hypericin when assembled into egg L-a-phosphatidylcholine liposomes. With respect to hypericin ethanol solutions, both absorption and fluorescence maxima are 5 nm red shifted when the pigment is inserted into the lipidic microenvironment, regardless of the hypericin local concentration. Increasing by 100 times the hypericin local concentration decreases the relative fluorescence quantum yield by a factor of around 150 and the fraction of thermally released energy, conversely, increases from 0.6 to 0.9. From the analysis of fluorescence lifetimes and their relative amplitudes it appears that a subnanosecond living component is predominant at the highest hypericin local concentrations.     

FLUORESCENCE FROM MAJOR AND MINOR BACTERIOCHLOROPHYLL COMPONENTS IN VIVO*

Abstract— In the photosynthetic bacteria Chromatium, Rhoahpirillum rubrum, and Rhodopseudomonus spheroides the fluorescence of bacteriochlorophyll is probably free of contamination by a “fast” component of delayed emission, judging from the characteristics of the delayed light measured 3 msec after excitation. In Rps. spheroides the pigment P870, associated with photochemical reaction centers, is non-fluorescent in its photochemically active state. Fluorescence of P870 can be induced by either of two agencies that suppress its photochemical activity: exposure to Na₂S₂O₄ and (in a dry chromatophore film) dessication. The yield of fluorescence from the major (light harvesting) component of bacteriochlorophyll in vivo is brought to a common maximum value by conditions that suppress the photochemical activity of P870. In addition to dessication and exposure to Na₂S₂O₄ these conditions include saturating illumination and exposure to K₃Fe(CN)₆. Of these four treatments only the last two bleach the long wave absorption band of P870. These experiments support the following assertions: (1) P870 traps singlet excitation energy absorbed by the light harvesting BChl; the trapping function of P870 depends on its ability to initiate and participate in photochemistry. (2) Both dessication and exposure to Na₂S₂O₄ suppress the photochemical activity of P870 by blocking an event that proceeds directly from the excited singlet state in P870. (3) The fluoresecence of BChl in vivo is emitted almost entirely by a major (light harvesting) component.     

抚顺烟煤及其抽出物的FTIR光谱结构表征

用富立叶变换红外光谱(FTIR)对抚顺烟煤的有机组分进行了测定。通过对谱图的解析,指出抚顺烟煤及其吡啶抽出物和抽提残煤在结构上的异同。以及抽出物各色谱馏分中存在的官能团和官能团之间极性的差异,对原煤整体结构提供了精细的结构信息。     

高能火花光源激发钢铁和铜合金中铝的看谱分析

采用高能火花光泊激钢铁和铜合金试样,借以进行铝的看谱分析,研究了在高能火花光源激发下光谱出现和其强度变化的规律以及以５６９．６５ｎｍ光谱区域的干扰情况。从而制 钢铁和铜合金中铝的看谱分析方法,并将其应用于生产实践中获得了令人满意的结果。是一种既经济简便及快速实用的分析测定方法 。     

IN VITRO AND IN VIVO PROTECTION AGAINST PHOTOTOXIC SIDE EFFECTS OF PHOTODYNAMIC THERAPY BY RADIOPROTECTIVE AGENTSWR–2721 ANDWR–77913

Abstract— The experimental radioprotective agentsS–2-(3-aminopropylamino) ethyl phosphorothioate(WR–2721) and 3-amino-2-hydroxypropyl phosphorothioate(WR–77913) are also protective against photosensitized oxidation. They reduce porphyrin-induced photopolymerization of lens cytosol proteins in vitro, and phototoxic damage to mouse skin in vivo. The phototoxic dose modification factor (DMF) was 1.5 which is similar to that found in ionizing radiation. Part of the mechanism by which sulfhydryls afford this protection is by accelerating photobleaching of the porphyrins.