Efficacy of dispersed fibrous carbon sorbent in treatment of malignant fungating wounds.

AIM: To evaluate the influence of dispersed fibrous carbon sorbent (DFCS) on malignant fungating wounds (MFWs) in Guerin's carcinoma-bearing rats with an assessment of wound bacterial microflora. MATERIALS AND METHODS: The study was performed on female Wistar rats inoculated subcutaneously with Guerin T8 carcinoma into the upper interscapular region. On day 20, the tumors were infected by injecting the suspension of S. aureus 8325-4. After 24 h, gauze dressings were applied daily to the wounds in the control group and DFCS in the experimental one. The state of the wounds was assessed by visual control with photo monitoring, odor control on a verbal rating scale and microbiological analysis of qualitative and quantitative characteristics of wound microbiota. RESULTS: On the 3rd day after the start of dressings, the number of S. aureus of 8325-4 strain was significantly higher in the wounds of rats in control group than experimental one (5.14 ± 0.27 vs 3.43 ± 0.33 lg CFU/ml). The total number of Staphylococci in the DFCS-treated wounds did not differ statistically from the number of S. aureus 8325-4 strain whereas in control ones were higher by an order of magnitude. On the 10th day the total number of Staphylococci and S. aureus 8325-4 in particular, remained consistently high in the wounds of the control rats, while was almost five orders of magnitude lower and represented mainly by S. aureus 8325-4 in the experimental ones. The total number of aerobic and optionally anaerobic microorganisms was significantly lower as well. A greater variety of microorganisms in the gauze-covered wounds, as well as an their increased number were accompanied by enhancement of the wound odor from "noticeable" to "strong". There was an appearance of a "barely noticeable" odor in only one animal from the experimental group. CONCLUSION: The study has demonstrated the ability of DFCS to control substantially the bacterial microflora as well as malodor of MWFs in vivo. The results obtained can contribute to solving the problem of improving the quality of palliative care for patients with malignant and other chronic wounds.

Comparative study of biochemical and morphological parameters in rats with Walker 256 and Walker 256/DOX carcinosarcoma.

AIM: To evaluate the changes of some biochemical blood plasma parameters and morphological structure of the internal organs of rats with transplanted doxorubicin (DOX)-sensitive (Walker 256) and doxorubicin-resistant (Walker 256/DOX) strains of Walker 256 carcinosarcoma. MATERIALS AND METHODS: The study was performed on female Wistar rats with transplanted Walker 256 or Walker 256/DOX and intact animals (control). On the 9th day after transplantation of tumor cells, a comparative analysis of some blood plasma biochemical parameters and morphological examination of the liver, kidneys, myocardium and spleen of rats was carried out. RESULTS: Walker 256 growth, in comparison with Walker 256/DOX, is accompanied by more pronounced systemic effect on tumor-bearing rats. Uric acid concentration in the blood plasma of Walker 256 bearing rats was significantly (by 15.5%) higher than in Walker 256/DOX bearing rats. Aspartate aminotransferase activity in the Walker 256 group was significantly (by 107.2%) higher than in Walker 256/DOX group, but alanine aminotransferase activity was 58.5% lower. 56.7% decrease of alkaline phosphatase in rats with Walker 256, and 21% increase of this index in rats with Walker 256/DOX were observed. The growth of Walker 256 carcinosarcoma led to greater structural damage of the liver, kidneys and spleen in experimental animals compared with Walker 256/DOX strain. CONCLUSION: Tumor growth in rats with Walker 256/DOX leads to less pronounced changes in the biochemical parameters of rat blood plasma and morphological structure of internal organs compared with wild-type carcinosarcoma.

Structural changes of serum albumin in response to oxidative stress caused by Walker-256 carcinosarcoma growth.

AIM: To assess oxidative stress and structural changes of the serum albumin in rats with transplanted Walker-256 carcinosarcoma (W256) strains with varying sensitivity to doxorubicin (Dox). MATERIALS AND METHODS: The study was performed on female Wistar rats with transplanted W256. On the 9th day after tumor cell transplantation an analysis of peripheral blood, oxidative stress parameters, and structural changes of serum albumin of experimental animals was performed. RESULTS: On the 9th day after W256 transplantation a significant increase in the leukocyte counts was observed in the groups of animals with the Dox-resistant and parental (Dox-sensitive) W256 tumors compared with the group of the intact animals: up to 14.24 ± 1.92 â€¢ 103/µl and 9.78 ± 1.03 â€¢ 103/µl, vs 8.92 ± 1.04 â€¢ 103/µl, respectively, due to the increase of granulocyte and monocyte counts. The number of lymphocytes was within the normal range. The level of hemoglobin and the erythrocyte counts were also within normal limits, but hematocrit in both groups of animals with tumors somewhat increased against the background of 1.2-fold elevation of the mean erythrocyte volume. In the group of rats with Dox-resistant W256, there was observed a decrease in the plateletcrit by almost 22% and thrombocyte counts - by 28%. Analysis of oxidative stress indices revealed a significant increase in the level of reactive oxygen species, 2-fold increase of malonic dialdehyde level and the degree of oxidative damage of blood plasma proteins, as well as a decrease in the activity of catalase in hemolysates (by 12-15%) in both groups of tumor-bearing rats. With the use of differential scanning calorimetry, UV and fluorescence spectroscopy we have revealed anomalous conformational changes of albumin caused by tumor development: structural rearrangements in the region of its first drug binding site located in the IIA domain, separation of globular parts of albumin molecule, and partial "opening" in a protein molecular three-domain structure resulting a loss of its thermal resistance. CONCLUSION: The development of transplanted Walker-256 carcinosarcoma, especially its Dox-resistant variant, results in severe metabolic intoxication reflected in alteration of hematological parameters, and indices of oxidative stress, as well as architectonic changes of serum albumin.

Adsorptive therapy as a modificator for tumor-host interaction.

The potential of one of the adsorption methods, enterosorption (ES), using the new generation of carbon adsorbents to correct the negative manifestations of tumor-host interaction in the framework of paraneoplastic syndrome (PNS) as well as systemic toxicity of chemo- and radiation therapy, is discussed. The ES influence on the development of PNS was demonstrated in C57/BL6 mice with transplanted Lewis lung carcinoma. Two-week administration of carbon enterosorbents resulted in a significant suppression of metastasis and correction of tumor-related anemia, activation of granulocytic line in the bone marrow with nearly 3-fold enhancement of its mitotic activity. ES exerted a positive influence on the structural-morphologic indexes and regenerative potential of kidneys and liver, mitigated manifestations of oxidative stress, decreased the level of endogenous intoxication, increased resistance of erythrocyte membranes and decreased ligand loading of blood plasma transport proteins. The effect of ES on anticancer activity and toxic reactions of cisplatin (CP) was evaluated in Guerin carcinoma-bearing rats. ES reduced significantly creatinine and other kidney biochemical indexes elevated in the blood plasma of rats after CP treatment. ES attenuated dystrophic changes in the histological structure of internal organs (kidney, liver, spleen), caused by tumor growth and significantly aggravated under the influence of CP. Such changes were specially traced in the kidneys and well reflect the nephroprotective potential of ES. In rats irradiated with X-ray in sublethal dose, highly activated granulated carbonic enterosorbents facilitated the restoration of white blood cells and lymphocyte count. The results obtained confirm the insights of academician R.E. Kavetsky predicting the future of adsorptive detoxification with activated carbons in the treatment of cancer patients.

Highly activated carbon enterosorbent mediates the suppression of paraneoplastic syndrome associated with Lewis lung carcinoma in mice.

AIM: To investigate the effect of enterosorption on the development of paraneoplastic syndrome in mice with Lewis lung carcinoma (LLC). MATERIALS AND METHODS: The study was performed on male С57/ВL6 mice with transplanted LLC. As an enterosorbent, highly activated powder fraction of HSGD was administered per os daily at a dose of 0.625 g/kg for two weeks starting from the 7th day after tumor cell transplantation. Analysis of hemo- and myelograms, morphological alterations in vital organs, the activities of catalase and superoxide dismutase, biochemical analysis of blood and quantitative analysis of hydroperoxides, malonic dialdehyde, аdvanced oxidation protein products was carried out by standard methods after completing the course of enterosorption. Ligand loading of blood plasma proteins was estimated by the method of differential scanning microcalorimetry. RESULTS: Administration of enterosorbent resulted in inhibition of LLC growth and in nearly 2-fold decrease of lung metastases number (p < 0.05). Activation of granulocytic line in the bone marrow with nearly 3-fold enhancement of mitotic activity took place after enterosorbent administration. Red cell lineage indices and bone marrow cellularity remained unaltered. After enterosorption session, the studied biochemical indices of peripheral blood evidenced on decreasing the endogenous intoxication and oxidative stress levels, improving the functional state of kidneys, increasing the resistance of erythrocyte membranes and lowering the ligand loading of blood plasma transport proteins. Morphological structure of kidneys and liver confirmed significant positive effect of enterosorption. The data of morphologic examination of gastric fundus, small intestine, and large bowel slides after 2-week administration of enterosorbent showed its high safety and proper evacuation from intestine. CONCLUSION: The two-week long enterosorption session in mice with LLC caused the suppression of tumor growth and metastasis, normalization of bone marrow hemopoiesis. Enterosorption exerted a positive influence on the structural-morphologic indexes and regenerative potential of kidneys and liver, mitigated manifestations of oxidative stress, decreased the level of endogenous intoxication, promoted deliganding of albumin molecule and deloading of erythrocyte membranes.

Chlorin e6 combined with albumin nanoparticles as a potential composite photosensitizer for photodynamic therapy of tumors.

AIM: To synthesize and to study for photodynamic activity a composite photosensitizer consisting of chlorin e6 and human serum albumin nanoparticles (HSA NPs). MATERIALS AND METHODS: Starting from sorption-purified HSA, the albumin nanoparticles with a different degree of lysine residues cross-linking (10; 20; 40, and 100%) were obtained by the coacervation method. The HSA NPs were used for synthesis of nanocomposites with chlorin e6 and fluorescein isothiocyanate (FITC)-labeled preparations. Malignant lymphocytes of the MT-4 (human T-cell leukemia) line and normal lymphocytes of healthy donors served as cell targets. For photodynamic treatment, a semiconductor laser was exploited as a light source, and cell viability was assessed by MTT or trypan blue dye exclusion tests. For cell imaging and HSA NPs visualization, the fluorescence microscopy and transmission electron microscopy were applied, respectively. C57Bl/6 mice were used in animal experiments. RESULTS: The absorption and fluorescence spectra of chlorin e6-HSA NPs composites were characterized, and by the electron microscopy investigation the size of NPs (nanospheres) was estimated: 100-120 nm. FITC-labeled albumin preparations allowed to establish that HSA NPs have much higher exposition and concentration dependent affinity to malignant cell surface than initial HSA. In experiments with MT-4 cells on PDT activity of chlorin e6-HSA NPs, the nanocomposite effectiveness elevated along with increasing percentage of cross-linked amino acid residues, and for the nanocomposite with 100% of albumin cross-linking it exceeded the activity of free chlorin e6. In contrast to malignant cells, the complexation of chlorin e6 with HSA NPs decreased its photodynamic effect on normal human lymphocytes. Intravenous introduction of the chlorin e6-HSA NPs composite to mice showed prolonged circulation of the nanocomposite in blood in comparison with free PS. CONCLUSION: Promising results obtained with chlorin e6-HSA NPs composites warrant conduction of full-fledged PDT studies in vivo using the nanocomposites as photosensitizers.

Effect of enterosorption on paraneoplastic syndrome manifestations in mice with highly angiogenic variant of Lewis lung carcinoma.

AIM: To study the correcting effects of microgranulated HSGD enterosorbent on hematological, morphological and biochemical indices of paraneoplastic syndrome in mice with highly angiogenic variant of Lewis lung carcinoma LLC/R9. METHODS: The study was performed on male С57/ВL6 mice with transplanted LLC/R9. Enterosorbent HSGD was administered daily at a dose of 0.625 g/kg for 2 weeks starting from 7(th) day after tumor cell transplantation. When enterosorption was completed, an analysis of peripheral blood, biochemical indices and morphological structure of tumor, lung, liver, spleen and thymus was carried out by standard methods. RESULTS: It has been shown that administration of enterosorbent did not affect LLC/R9 growth but resulted in nearly two fold decrease of the volume of lung metastases (p < 0.05). Erythrocyte number and hemoglobin level were higher by 30.0% (p < 0.05) and 23.3% (p < 0.05), respectively, in mice treated with enterosorbents as compared to untreated animals. In addition sorbent treatment completely normalized the thrombocyte index resulting in elevation of platelet number by 54.5% (p < 0.01) up to their level in intact mice. The morphological examination of liver and biochemical analysis of peripheral blood evidenced on significant positive correcting effect of enterosorption on histological structure of this organ and its functional activity. Normalization of total proteins and serum albumin level as well as significant decrease of total lipid concentration by 29% (p < 0.01) in blood of treated mice were observed. CONCLUSION: Positive influence of microgranulated carbon sorbent on some hematological, morphological and biochemical indices of tumor associated symptoms in LLC/R9-bearing mice denotes that enterosorption-based therapy can be considered as a prospective treatment for correction of some paraneoplastic syndrome signs in cancer patients.

Optimization of physico-chemical properties of carbon enterosorbents and evaluation of their sorption activity for use in the treatment of paraneoplastic syndrome and other endogenous intoxications in cancer patients.

AIM: Development of carbon enterosorbents with optimal physical-chemical properties and high adsorptive capacity for their usage in the treatment of paraneoplastic syndrome and other endogenous intoxication in cancer patients. METHODS: physical-chemical and biochemical methods of investigation. RESULTS: In the work it has been shown that performance of additional steam activation on pilot plant developed in R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology NAS of Ukraine, allows produce highly active granulated and fibrous carbon enterosorbents which possess well developed porous surface providing potent sorption potential toward compounds of hydrophilic and hydrophobic nature. Being placed in gastro-intestinal tract lumen these sorbents may cause certain effect on functional activity of detoxifying body systems and regeneration potential of many organs and tissues. CONCLUSION: The usage of carbon enterosorbents with optimal physical-chemical properties and high adsorptive capacity could be very perspective for correction of biochemical, immunologic, morphologic and hematological manifestations of paraneoplastic syndrome.

Carbon adsorbents in oncology: achievements and perspectives.

The results of own investigations and literature data are summarized to determine the place of the main methods of adsorption therapy in complex treatment of the patients with malignant tumors. New possibilities for the usage of new generation of carbon adsorbents and modern adsorptive technologies in cancer treatment are discussed.

New approaches to the removal of protein-bound toxins from blood plasma of uremic patients.

The article is devoted to the theoretical aspects of the development of the effective method for the removal of protein-bound uremic toxins. It is shown that the methods of flow and differential scanning microcalorimetry are sufficient enough for the evaluation of the degree of ligand loading of human serum albumin with protein-bound uremic toxins. The molecules of albumin isolated from blood plasma of the patients being kept on chronic dialysis are demonstrating significant alterations of conformation and complex-forming properties, the correction of which by conventional methods of extracorporeal detoxification (exhaustive dialysis, treatment on synthetic SCN carbons) are practically ineffective. Deliganding of uremic albumin may be successfully performed on conventional carbon haemosorbents upon preliminary separation of blood plasma and its dilution with acetate buffer 1:1 at pH = 5.08. Treatment of the whole blood of patients onto new mass-fractal deliganding carbon, i.e., hemosorbents of HSGD trademark. These HSGD haemosorbents quite effectively could be used for restoration of main parameters of uremic HAS molecules conformation and ligand-binding activity simultaneously with hemodialysis upon the protection by locally performed citrate anticoagulation as an easier and cheaper method for the removal of protein-bound uremic toxins.

The study of possibility to elevate antitumor activity and decrease of systemic toxic effects of cisplatin by its binding with deliganded albumin.

AIM: To evaluate antitumor and toxic action of cisplatin (CP) in non-bound form and in a complex with deliganded albumin. METHODS: To study complex-formation between CP and albumin, differential scanning and isothermic flow microcalorimetry were used. For quantitive evaluation of albumin-bound CP, the method of ultrafiltration was applied. Concentration of platinum in the samples was determined by atomic-absorption spectral analysis. Antitumor and toxic effect of CP and CP-albumin complex was studied in vivo using Guerin carcinoma (GC) model. RESULTS: It has been shown that the second drug-binding site, located in the III domain of albumin molecule is one of the main points of binding of CP. Purification of officinal human serum albumin (HSA) on highly active carbon hemosorbents of HSGD mark allows to obtain deliganded albumin (dHSA) with elevated complex-forming ability toward CP. Administration of CP-dHSA complex provides higher rate of GC growth inhibition, than that of CP, and the content of creatinine in blood plasma of GC-bearing rats increases by 15% versus 40% in the case of CP administration. CONCLUSION: The data obtained allow recommend application of CP-dHSA to complex for enhancement of antitumor action and decrease of toxic effects of cisplatin.

Mathematical model of binding of albumin-bilirubin complex to the surface of carbon pyropolymer.

We proposed a mathematical model and estimated the parameters of adsorption of albumin-bilirubin complex to the surface of carbon pyropolymer. Design data corresponded to the results of experimental studies. Our findings indicate that modeling of this process should take into account fractal properties of the surface of carbon pyropolymer.

Structure and binding properties of serum albumin in uremic patients at different periods of hemodialysis.

Few diagnostic methods are available that describe uremia related changes of the albumin molecule structure in hemodialysis patients. The impaired human serum albumin (HSA) function is an essential part of the uremic syndrome and probably influences the long-term outcome of patients on maintenance dialysis. The albumin binding capacity (characterized for different binding centers on the molecule) is one of the relevant clinical parameters. During the current study, marker substances were utilized to evaluate center-specific binding capacity. Patients were divided into 3 groups depending on the time on hemodialysis (HD) treatment (in years) with healthy blood donors as control. Compared to healthy persons, results demonstrate a considerable impairment of binding characteristics in HD patients. Only in patients on maintenance HD for more than 5 years did ligand binding properties improve significantly. A correlation between the time of chronic HD and the recovery in binding capacity was found for the majority of binding centers of the HSA molecule. Similar results were seen applying such analytical methods as thermography (melting points) and thermofluorescence. Binding capacity impairment found for specified binding centers on the HSA molecule as the main serum carrier protein may have a direct impact on different clinical situations and the HD long-term outcome.

Peritoneal dialysis for the removal of protein-bound markers of hepatic insufficiency.

The addition of human serum albumin (HSA) to peritoneal dialysate increases the clearance of bilirubin in rats suffering from obstructive jaundice. The acceptor properties of the fluid can be enhanced by using HSA that does not contain standard stabilizing additives and has been purified by further adsorption on activated carbon. Bilirubin-containing dialysate fluid, as well as the ascitic fluid of cirrhotic patients, can be regenerated by a combination of membrane ultrafiltration and carbon adsorption. These observations suggest a potentially useful scheme for continuous, regenerative peritoneal dialysis in the treatment of hepatic insufficiency.

High-porosity activated carbons for bilirubin removal.

The aim of this study was to clarify the relationship between the extent of activation of synthetic granula and fibrous carbons and the adsorption of bilirubin from protein solutions. The total pore volumes of granular carbons START, SCN and fibrous activated carbons ACFM were 0.9-2.2. cm3/g and 0.8-1.5 cm3/g, respectively. A parallel increase in volume and specific surface area of micropores lead to a 4-5-fold increase of bilirubin adsorption from a 3% HSA solution. About 3 mg of bilirubin per 1 ml of the working column volume is removed from the solution with a 18 mg/100 ml concentration, after 8 min contact with an adsorbent after 4 hours of perfusion. Removal of bilirubin from model solutions means the conformation of albumin molecules can be restored. Carbon adsorbents synthesized for the elimination of bilirubin from protein-containing solutions can also be called deliganding adsorbents, since under some experimental conditions they eliminate other protein-bound ligands, viz. phenols by 97-99%, bile acids by 90-92% and sodium caprylate by 89-95%.