Untitled

Джагаров, Б. М.; Zhavrid, Edvard; Istomin, Yu. P.; Chalov, V. N.

doi:10.1023/a:1019255817114

Cited by 7 publications

(8 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Application of laser-induced photodissociation provides a unique option for locally increasing the free oxygen concentration in tissues. We should note that increased oxygen concentration in tissues plays an important role in the in vivo enhancement of many photochemical reactions, including cell metabolism.The proposed hypothesis and the developed concept of laser-induced photodissociation of HbO 2 were confirmed in vivo in [12,13]. In [12], it was shown that when arterial blood is exposed to low-intensity laser radiation through the skin, the oxygen saturation (SaO 2 , the degree of saturation of blood hemoglobin by oxygen) decreases.…”

mentioning

confidence: 91%

“…The proposed hypothesis and the developed concept of laser-induced photodissociation of HbO 2 were confirmed in vivo in [12,13]. In [12], it was shown that when arterial blood is exposed to low-intensity laser radiation through the skin, the oxygen saturation (SaO 2 , the degree of saturation of blood hemoglobin by oxygen) decreases.…”

mentioning

confidence: 91%

“…Since free oxygen is an integral part and a necessary component for the photodynamic response, the efficacy of photodynamic therapy increases when laser-induced photodissociation of HbO 2 is used [13]. Obviously raising the Fig.…”

Section: Introductionmentioning

confidence: 99%

“…In [12], it was shown that when arterial blood is exposed to low-intensity laser radiation through the skin, the oxygen saturation (SaO 2 , the degree of saturation of blood hemoglobin by oxygen) decreases. In [13], laser-induced photodissociation of HbO 2 was used to improve the efficacy of photodynamic therapy. In experiments on animals, it was established that supplying additional free molecular oxygen to tumor tissue by means of laser-induced dissociation of HbO 2 substantially increases the therapeutic effect of photodynamic therapy.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Effect of temperature on the quantum yield of laser-induced photodissociation of oxyhemoglobin in vivo

Asimov

Asimov²,

Рубинов

et al. 2006

J Appl Spectrosc

View full text Add to dashboard Cite

We have studied the effect of temperature on laser-induced photodissociation of oxyhemoglobin in vivo by recording the change in the oxygen saturation of arterial blood. We have established that on exposure to lowintensity laser radiation, the local concentration of free oxygen in tissue significantly increases for a body temperature above 40 o C, compared with the normal temperature. We demonstrate a unique option for selectively and locally increasing the concentration of free molecular oxygen in tissue, which promotes enhancement of cell metabolism. We consider the possibilities for biomedical use of this phenomenon. The results obtained show that the temperature dependence of the quantum yield for photodissociation of oxyhemoglobin should be considered in development of new therapeutic methods for laser medicine.Introduction. Optical laser technologies have found practical application in various fields of modern medicine. For example, the biostimulating and therapeutic effect of low-intensity laser radiation is widely used [1][2][3][4], in particular in laser therapy of skin diseases (ulcers, wounds, burns, bedsores, and anaerobic infections). Photodynamic therapy (PDT) has been intensively used for cancer treatment [5][6][7].In [8], for the first time we advanced the hypothesis that photodissociation of oxyhemoglobin (HbO 2 ) has a role in the mechanism for the biostimulating and therapeutic effect of low-intensity laser radiation. Based on this hypothesis, we developed the concept of laser-induced photodissociation of HbO 2 and its use in biomedical practice [9][10][11]. Application of laser-induced photodissociation provides a unique option for locally increasing the free oxygen concentration in tissues. We should note that increased oxygen concentration in tissues plays an important role in the in vivo enhancement of many photochemical reactions, including cell metabolism.The proposed hypothesis and the developed concept of laser-induced photodissociation of HbO 2 were confirmed in vivo in [12,13]. In [12], it was shown that when arterial blood is exposed to low-intensity laser radiation through the skin, the oxygen saturation (SaO 2 , the degree of saturation of blood hemoglobin by oxygen) decreases. In [13], laser-induced photodissociation of HbO 2 was used to improve the efficacy of photodynamic therapy. In experiments on animals, it was established that supplying additional free molecular oxygen to tumor tissue by means of laser-induced dissociation of HbO 2 substantially increases the therapeutic effect of photodynamic therapy. At the same time, the increase in oxygen concentration is limited by the low quantum yield for photodissociation of HbO 2 (<10%) [14]. Accordingly, a promising approach would seem to be to investigate the possibility of increasing the quantum yield for photodissociation of HbO 2 by raising the temperature of the tissue. The temperature dependence of the quantum yield of HbO 2 was studied in vitro in [15].

show abstract

mentioning

confidence: 91%

mentioning

confidence: 91%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Effect of temperature on the quantum yield of laser-induced photodissociation of oxyhemoglobin in vivo

Asimov

Asimov²,

Рубинов

et al. 2006

J Appl Spectrosc

View full text Add to dashboard Cite

show abstract

“…Figures 2 and 3 show very typical photographs of the tumor slices, processed using the "Damage of Tumor" program and the proposed procedure. The dependence of the size of tumor necrosis on the conditions for irradiation of sensitized and nonsensitized tissues by light is discussed in more detail in [3][4][5]11]. In addition to the size of ne- crosis, we need to focus on the different types of destruction of the tumors depending on the irradiation conditions.…”

mentioning

confidence: 99%

Procedure for quantitative determination of effectiveness of photoinduced destruction of malignant tumors

Bizyuk

Istomin²,

Джагаров

2006

J Appl Spectrosc

Self Cite

View full text Add to dashboard Cite

We have developed a procedure for analysis of the functional status of blood vessels in tumor tissues using computer-assisted color scanning of tumor slices and also for a quantitative assessment of the effectiveness of photoinduced destruction of tumor tissues in animal experiments. Its major advantage is direct determination of the size of the tumor necrosis zone. The procedure has been tested in an experiment on three strains of malignant tumors with different morphologies.

show abstract

Mechanism of complexing of chlorin e 6 and tetra(p-carboxyphenyl)porphyrin with malate dehydrogenase

et al. 2005

View full text Add to dashboard Cite

The mechanism of complexing of the tetrapyrrole-nature photodynamic sensitizers chlorin e 6 and tetra (p-carboxyphenyl)porphyrin (TCPP) with the Krebs-cycle enzyme malate dehydrogenase (MDG) has been investigated by spectral-luminescence methods. It is shown that each subunit entering into the composition of the MDG dimer molecule forms an equilibrium complex with one dye molecule. However, if the sites of bonding of TCPP on a protein molecule are independent, the MDG-chlorin e 6 complex has a negative cooperativity since after the dye is incorporated into the first subunit of the macromolecule, its penetration to the second subunit becomes difficult. This is explained by the fact that conformation transformations, arising as a result of the incorporation of chlorin into one of the MDG subunits, are transferred to the site of its bonding on other MDG subunits through the intersubunit contacts of the enzyme. It has been established that photosensitizers compete with the hydrophobic fluorescent probe 8-aniline-1-naphthalenesulfonate (ANS) (whose position in the MDG macromolecule was described in detail in the literature) for the sites of bonding on the protein molecule, which allows the conclusion that TCPP and chlorin e 6 are localized in the catalytic domain of MDG. In this case, the sites of bonding of these dyes and the sites of bonding of nicotinamide-adenine dinucleotide, occupying the MDG domain that bonds coenzymes, do not interact with each other.

show abstract

Untitled

Cited by 7 publications

References 4 publications

Effect of temperature on the quantum yield of laser-induced photodissociation of oxyhemoglobin in vivo

Effect of temperature on the quantum yield of laser-induced photodissociation of oxyhemoglobin in vivo

Procedure for quantitative determination of effectiveness of photoinduced destruction of malignant tumors

Mechanism of complexing of chlorin e 6 and tetra(p-carboxyphenyl)porphyrin with malate dehydrogenase

Contact Info

Product

Resources

About