The effects of 1st and 2nd generation biodiesel exhaust exposure on hematological and biochemical blood indices of Fisher344 male rats - The FuelHealth project.

Diesel exhaust emissions (DEE), being one of the main causes of ambient air pollution, exert a detrimental effect on human health and increase morbidity and mortality related to cardiovascular and pulmonary diseases. Therefore, the objective of the present study was to investigate potential adverse effects of exhausts emissions from B7 fuel, the first-generation biofuel containing 7% of fatty acid methyl esters (FAME), and SHB20 fuel, the second-generation biofuel containing 20% FAME/hydrotreated vegetable oil (HVO), after a whole-body exposure with and without diesel particle filter (DPF). The experiment was performed on 95 male Fischer 344 rats, divided into 10 groups (8 experimental, 2 control). Animals were exposed to DEE (diluted with charcoal-filtered room air to 2.1-2.2% (v/v)) for 7 or 28 days (6 h/day, 5 days/week) in an inhalation chamber. DEE originated from Euro 5 engine with or without DPF treatment, run on B7 or SHB20 fuel. Animals in the control groups were exposed to clean air. Our results showed that the majority of haematological and biochemical parameters examined in blood were at a similar level in the exposed and control animals. However, exposure to DEE from the SHB20 fuel caused an increase in the number of red blood cells (RBC) and haemoglobin concentration. Moreover, 7 days exposure to DEE from SHB20 fuel induced genotoxic effects manifested by increased levels of DNA single-strand breaks in peripheral blood lymphocytes. Furthermore, inhalation of both types of DEE induced oxidative stress and caused imbalance of anti-oxidant defence enzymes. In conclusion, exposure to DEE from B7, which was associated with higher exposure to polycyclic aromatic hydrocarbons, resulted in decreased number of T and NK lymphocytes, while DEE from SHB20 induced a higher level of DNA single-strand breaks, oxidative stress and increased red blood cells parameters. Additionally, DPF technology generated increased number of smaller PM and made the DEE more reactive and more harmful, manifested as deregulation of redox balance.

The first gamma-H2AX biodosimetry intercomparison exercise of the developing European biodosimetry network RENEB.

In the event of a mass casualty radiation incident, the gamma-H2AX foci assay could be a useful tool to estimate radiation doses received by individuals. The rapid processing time of blood samples of just a few hours and the potential for batch processing, enabling high throughput, make the assay ideal for early triage categorisation to separate the 'worried well' from the low and critically exposed by quantifying radiation-induced foci in peripheral blood lymphocytes. Within the RENEB framework, 8 European laboratories have taken part in the first European gamma-H2AX biodosimetry exercise, which consisted of a telescoring comparison of 200 circulated foci images taken from 8 samples, and a comparison of 10 fresh blood lymphocyte samples that were shipped overnight to participating labs 4 or 24 h post-exposure. Despite large variations between laboratories in the dose-response relationship for foci induction, the obtained results indicate that the network should be able to use the gamma-H2AX assay for rapidly identifying the most severely exposed individuals within a cohort who could then be prioritised for accurate chromosome dosimetry.

Time-dependent biodistribution and excretion of silver nanoparticles in male Wistar rats.

Silver nanoparticles (AgNPs) are the most commonly used nanoparticles owing to their antimicrobial properties. The motivation of the present study was (1) to analyze the effect of silver particle size on rat tissue distribution at different time points, (2) to determine the accumulation of AgNPs in potential rat target organs, (3) to analyze the intracellular distribution of AgNPs and (4) to examine the excretion of AgNPs by urine and feces. AgNPs were characterized by dynamic light scattering (DLS), zeta potential measurements, BET surface area measurements, transmission and scanning electron microscopy. AgNPs (20 and 200 nm) were administered intravenously (i.v.) to male Wistar rats at a dose of 5 mg kg(-1) of body weight. Biological material was sampled 24 h, 7 and 28 days after injection. Using inductively coupled plasma-mass spectrometry (ICP-MS) and transmission electron microscopy (TEM) it was observed that AgNPs translocated from the blood to the main organs and the concentration of silver in tissues was significantly higher in rats treated with 20 nm AgNPs as compared with 200 nm AgNPs. The highest concentration of silver was found in the liver after 24 h. After 7 days, a high level of silver was observed in the lungs and spleen. The silver concentration in the kidneys and brain increased during the experiment and reached the highest concentration after 28 days. Moreover, the highest concentration of AgNPs was observed in the urine 1 day after the injection, maintained high for 14 days and then decreased. The fecal level of silver in rats was the highest within 2 days after AgNPs administration and then decreased.

Dihydropyridines decrease X-ray-induced DNA base damage in mammalian cells.

Compounds with the structural motif of 1,4-dihydropyridine display a broad spectrum of biological activities, often defined as bioprotective. Among them are L-type calcium channel blockers, however, also derivatives which do not block calcium channels exert various effects at the cellular and organismal levels. We examined the effect of sodium 3,5-bis-ethoxycarbonyl-2,6-dimethyl-1,4-dihydropyridine-4-carboxylate (denoted here as DHP and previously also as AV-153) on X-ray-induced DNA damage and mutation frequency at the HGPRT (hypoxanthine-guanine phosphoribosyl transferase) locus in Chinese hamster ovary CHO-K1 cells. Using formamido-pyrimidine glycosylase (FPG) comet assay, we found that 1-h DHP (10nM) treatment before X-irradiation considerably reduced the initial level of FPG-recognized DNA base damage, which was consistent with decreased 8-oxo-7,8-dihydro-2'-deoxyguanosine content and mutation frequency lowered by about 40%. No effect on single strand break rejoining or on cell survival was observed. Similar base damage-protective effect was observed for two calcium channel blockers: nifedipine (structurally similar to DHP) or verapamil (structurally unrelated). So far, the specificity of the DHP-caused reduction in DNA damage - practically limited to base damage - has no satisfactory explanation.

Effect of the heating temperature on the corrosion resistance of alkali-treated titanium.

The paper presents the results of examinations of the corrosion resistance of titanium after its being subjected to the surface modification by the alkali- and heat-treatments. The material examined was commercially pure titanium (grade 2). The samples were soaked in an aqueous 10M NaOH solution at 60 degrees C for 24 h and subsequently heated at 500, 600, or 700 degrees C for 1 h. The chemical composition of the surface layers was determined by X-ray photoelectron spectroscopy and secondary ion mass spectroscopy. The phases present in the layers were identified by XRD. The corrosion resistance was evaluated by electrochemical methods (Stern's method, potentiodynamic method, and impedance spectroscopy) at a temperature of 37 degrees C after short- and long-time exposures. The 13 h exposure was aimed to allow the corrosion potential to stabilize. The aim of the long-term exposures was to examine how the corrosion resistance of the modified samples changes during the exposure. Under the conditions prevailing during the experiments, the highest corrosion resistance was achieved with the samples heated at a temperature of 700 degrees C.

Differential DNA double strand break fixation dependence on poly(ADP-ribosylation) in L5178Y and CHO cells.

PURPOSE: To investigate the role of poly(ADP-ribosylation) in DNA double-strand break repair and fixation in murine lymphoma L5178Y (LY) sublines, LY-R and LY-S, and a pair of Chinese hamster ovary lines: wild-type and mutant xrs6 cells, that have differences in repair competence and degree of radiosensitization with poly(ADP-ribosylation) inhibitors. MATERIALS AND METHODS: Cells (asynchronous, logarithmic phase) were pre-incubated with 2 mM aminobenzamide at 37 or 25 degrees C, X-irradiated with 10 Gy and allowed to repair DNA breaks for 15, 60 and 120 min at 37 or 25 degrees C. The remaining double-strand break were estimated by the neutral comet assay. RESULTS: At 37 degrees C, no effect of AB treatment on the repair kinetics was observed either in xrs6 or Chinese hamster ovary (wild-type) cells. In contrast, aminobenzamide decreased the repair of double-strand break in the LY-S line but not the LY-R line, in agreement with the previously observed radiosensitization of LY cells by poly(ADP-ribosylation) inhibition. However, double-strand break rejoining in the repair competent cell lines, Chinese hamster ovary and LY-R, also was affected by aminobenzamide when the post-irradiation incubation was carried out at 25 degrees C. Analysis of these results together with earlier data on LY-S cells have been interpreted in terms of Radford's model of radiation damage fixation. CONCLUSION: The reported results indicate that poly(ADP-ribosylation) can be an important modulator of the conversion of DNA damage to lethal events.

Radiation sensitivity and the status of some radiation sensitivity markers in relatively sensitive lymphoid cells.

The most commonly used indicators of ionizing radiation exposure are cytogenetic measures and survival parameters. All these methods have their advantages, disadvantages and uncertainties, such that better biological estimators of the absorbed dose, especially in the low dose range, are being sought. In this study we analyzed apoptosis and several proteins involved in the regulation of apoptosis as possible indicators of irradiation after relatively small doses (0.1-2 Gy) of X-rays. The studies were carried out in seven lymphoid cell lines: two mouse lymphoma L5178Y, the human pre-B cell leukemia Reh, and four human Epstein-Barr virus-transformed lymphoid cell lines (two apparently normal and two Ataxia-telangiectasia (AT)). We detected apoptosis with the in situ terminal deoxynucleotidyl transferase assay and flow cytometry, and measured the expression of several apoptotic-regulatory proteins (Bcl-2, Bax, Bclx, NF kappa B) with Western blotting. The cytokinesis-block micronucleus assay, comet assay as a measure of DNA damage, and trypan blue survival test were also done for comparison Although for the most of examined parameters of radiation sensitivity: i.e. micronucleus assay, trypan blue test and percentage of apoptosis--there were observed clear dose-effect relationships for all cell lines examined, we did not find agreement between values for these measured parameters. There are marked differences in both timing of apoptosis and percentage of apoptotic cells. Variation in the apoptotic fraction in the controls for different sets of experiments is not very pronounced. There is however considerable variation for the same parameters in irradiated cells, possibly due to their cell cycle status during irradiation, as the cultures were not synchronized. Overall, neither the numbers of apoptotic cells nor the expression of apoptosis-related proteins, nor DNA repair can serve as dose estimators or sensors for these lines, but still these parameters can give valuable supplementary information about radiation sensitivity.

In vitro genotoxicity of ethanol and acetaldehyde in human lymphocytes and the gastrointestinal tract mucosa cells.

The influence of ethanol and acetaldehyde on DNA in human lymphocytes, gastric mucosa (GM) and colonic mucosa (CM) was investigated by using the comet assay. All kinds of cells were exposed to ethanol and acetaldehyde in two regimens: the cells were incubated with either chemical and analysed or they were exposed first to ethanol, washed and then exposed to acetaldehyde and analysed. Lymphocytes were exposed to ethanol at final concentrations of 30 mM and acetaldehyde at 3 mM. GM cells were incubated with ethanol at 1 M and acetaldehyde at 100 mM. CM cells were exposed to ethanol at 10 mM and acetaldehyde at 100 mM. In combined exposure, the cells were subsequently exposed to ethanol and acetaldehyde at all combination of the concentrations of the agents. Ethanol caused DNA strand breaks, which were repaired during 4 hr, except when this agent was applied in GM cells at a concentration of 1 M. A dose-dependent decrease in the tail moment of all types of acetaldehyde-treated cells was observed. Similar results were obtained when a recognized DNA crosslinking agent, formaldehyde, was used. These results suggest that acetaldehyde may form crosslinks with DNA. These crosslinks were poorly repaired. CM cells showed the highest sensitivity of all cell types to ethanol than lymphocytes and GM cells. There were no differences in the sensitivity to acetaldehyde of all the cell types. Our results clearly indicate that ethanol and acetaldehyde can contribute to cancers of the digestive tract.

DNA damage and repair in human lymphocytes exposed to three anticancer platinum drugs.

Cisplatin is a widely used anticancer drug, but its application is limited due to severe side effects. To reduce these effects, many other platinum drugs have been synthesized. In the present work comparative analysis of the toxicity of cisplatin, oxoplatin, and a conjugate (NH(3))(2)Pt(SeO(3)) (Se-Pt) in terms of cell viability, DNA binding, and DNA damage and repair in human lymphocytes was performed using the Trypan blue exclusion test, atomic absorption spectroscopy, and the comet assay, respectively. Cisplatin and oxoplatin did not cause a significant change in the viability of the lymphocytes even at the highest used concentration (750 microM), but the conjugate dramatically diminished viability at 100 microM only about 60% of the lymphocytes were viable (P < 0.05), and at 750 microM, less than 20% (P < 0.001). Se-Pt bound to isolated DNA was about 100 times weaker than the remaining two compounds; the binding of cisplatin was about 30% stronger than oxoplatin. Cisplatin and oxoplatin formed crosslinks with DNA in lymphocytes, whereas the conjugate induced DNA strand breaks. The lesions evoked by cisplatin and oxoplatin were slowly removed, but damage induced by Se-Pt was not repaired after 5 h even at a drug concentration of 10 microM. Severe cytotoxic and genotoxic effects exerted by Se-Pt in normal human lymphocytes preclude its intravenous application in cancer therapy. Teratogenesis Carcinog. Mutagen. 20:119-131, 2000.

Genotoxicity of chromium in human gastric mucosa cells and peripheral blood lymphocytes evaluated by the single cell gel electrophoresis (comet assay).

Hexavalent chromium compounds are well-recognized carcinogens. They easily penetrate the cell membrane and are reduced inside the cell to their trivalent form, which is supposed to react directly with DNA. Chromium is present in some workplaces as well as in water resources and food chain, so it can interact with the mucosa of the gastrointestinal tract. In order to elucidate the genotoxic potency of chromium in human gastric mucosa (GM) cells, the DNA-damaging effect of potassium dichromate (K2Cr2O7) was investigated using alkaline single cell gel electrophoresis (comet assay). Biopsy samples were obtained during gastroscopy from macroscopically healthy tissue of the stomach. Parallel test with human peripheral blood lymphocytes was also performed. Both types of cells were incubated at 37 degrees C with 1.6 mM of K2Cr2O7 for 1 h and after washing, were placed in a chromium-free medium to examine DNA repair. Alkaline single cell gel electrophoresis (comet assay) was used to assess DNA damage and repair. Chromium introduced a damage to DNA both in the GM cells and lymphocytes. The effect induced by K2Cr2O7 in GM cells was comparable with that caused in the lymphocytes. Treated cells were able to recover within a 60-min incubation in a chromium-free medium at 37 degrees C. The results obtained indicate that hexavalent chromium compounds, which may be found in the diet, can interact directly with DNA of the mucosa of the stomach.

DNA damage and repair in human lymphocytes and gastric mucosa cells exposed to chromium and curcumin.

Human population can be considered as a subject of combined exposure to chemicals. Hexavalent chromium is a well-known mutagen and carcinogen. Curcumin, a popular spice and pigment, is reported to have antineoplastic properties. The single cell gel electrophoresis (Comet assay) is a sensitive technique that allows detecting double- and single-strand DNA breaks caused by a broad spectrum of mutagens. In the present work the ability of curcumin to reduce DNA damage induced by chromium in human lymphocytes and gastric mucosa (GM) cells was investigated by using the comet assay. Chromium at 500 microM evoked DNA damage measured as significant (P < 0.001), about a two-fold increase in comet tail moment of both lymphocytes and GM cells. Curcumin at 10, 25, and 50 microM also damaged DNA of both types of cells in a dose-dependent manner: the increase in the tail moment reached about twenty times of the control value (P < 0.001). The combined action of chromium at 500 microM and curcumin at 50 microM resulted in the significant (P < 0.001) increase in the comet tail moment of both types of cells. In each case, treated cells were able to recover within 60 min. Our study clearly demonstrates that curcumin does not inhibit DNA damaging action of hexavalent chromium in human lymphocytes and GM cells. Moreover, curcumin itself can damage DNA of these cells and the total effect of chromium and curcumin is additive. Further studies are needed to establish the role of interaction of curcumin with DNA in carcinogenesis.

Lack of adverse effect of smoking habit on DNA strand breakage and base damage, as revealed by the alkaline comet assay.

In our preceding papers [M. Wojewódzka, M. Kruszewski, T. Iwanenko, A.R. Collins, I. Szumiel, Application of the comet assay for monitoring DNA damage in workers exposed to chronic low dose irradiation: I. Strand breakage, Mutat. Res., 416 (1998) 21-35; M. Kruszewski, M. Wojewódzka, T. Iwanenko, A.R. Collins, I. Szumiel, Application of the comet assay for monitoring DNA damage in workers exposed to chronic low dose irradiation: II. Base damage, Mutat. Res. , 416 (1998) 37-57.], we evaluated the DNA breakage and base damage with the use of comet assay in a group of 49 workers chronically exposed to low doses of ionizing radiation. There was a statistically significant difference in the damage levels between the hazard and control group. In this paper we describe a confounding lack of effect of the smoking habit on the DNA damage in the tested groups. The genotoxic effect of the smoking habit, as well as its modifying effect on genome damage inflicted by other agents, have been firmly established. However, no statistically significant effect of smoking was found in our study, neither in the control nor in the hazard group. This lack of effect was seen in all DNA damage determinations, both direct (DNA strand breakage and alkali-labile lesions) and enzyme-combined (base damage) and did not depend on the comet parameters, which were taken as damage indicators.

Differential inhibitory effect of OK-1035 on DNA repair in L5178Y murine lymphoma sublines with functional or defective repair of double strand breaks.

Radiosensitive L5178Y-S (LY-S) subline and its parental, more radioresistant L5178Y-R (LY-R) subline differ in DNA double strand break (DSB) rejoining. In this work we examined by comet assay the repair of X-ray-induced DNA damage in LY cells treated with OK-1035, a potent DNA-PK inhibitor. The unirradiated cells differ: the respective tail moment values for LY-R and LY-S cells were 9.62+/-2.84 and 3.52+/-0.1, reflecting the susceptibility to lysis conditions as well as the possible endogenous (oxidative) damage level. The level of initial DNA damage measured after irradiation (8 Gy) at DNA-denaturing pH was the same in both LY sublines: the mean tail moment values +/- SD were 92.93+/-10.39 for LY-R cells and 94.93+/-12.94 for LY-S cells. In LY-S cells the repair of 8 Gy X-ray-induced damage proceeded identically in the presence or absence of 2 mM OK-1035 to the same level of residual damage. In contrast, the level of residual damage in inhibitor treated LY-R cells was considerably higher than that in the untreated cells. Moreover, the inhibitor affected LY-R cells in G1 and S phases and not those in G2, in agreement with cell-cycle specificity of DNA-PK. These results may indicate that the DSB repair defect previously identified in LY-S cells is due to a lack of function of DNA-PK or its impaired activation in the irradiated cells.

Application of the comet assay for monitoring DNA damage in workers exposed to chronic low-dose irradiation. II. Base damage.

In the preceding paper [M. Wojewodzka, M. Kruszewski, T. Iwanenko, A.R. Collins, I. Szumiel, Application of the comet assay for monitoring DNA damage in workers exposed to chronic low dose irradiation. I. Strand breakage., Mutat. Res. 416 (1998) 21-35], we reported the results of DNA damage examination carried out for a group of people (49 individuals) professionally at risk of exposure to low doses of ionizing radiation as measured by the alkaline comet assay. Here, we used the method in combination with oxidative base damage-specific endonucleases to estimate base damage in the same individuals. These were endonuclease III (endoIII) and formamidopyrimidine glycosylase (FPG). In contrast to the previous investigations, we found no statistically significant difference in base damage between the control and hazard groups. Interestingly, the hazard group exhibited lower level of enzyme-sensitive sites than the control; however, this different was not significant. No correlation of base damage with age was found, similarly as in the case of DNA damage measured by the alkaline comet assay. Interindividual variability of base damage precluded exposure estimation for single individuals, since several members of the control group exhibited high comet parameters.

Application of the comet assay for monitoring DNA damage in workers exposed to chronic low-dose irradiation. I. Strand breakage.

We examined a group of people professionally at risk of exposure to low doses of ionizing radiation (altogether 49 individuals). Age, use of therapeutic drugs, work-related exposure to hazardous agents, previous exposures to diagnostic X-rays, such as patient and nuclear medical examination, were registered. For each individual, the occupational radiation burden received over the past period of 5 years was taken from the official personal records based on film dosimetry controlled every month. A matched group of controls was chosen among the administrative employees (40 individuals). The mean age of the studied population at the time of blood sampling was 49 years (range 24-69). The individuals were divided into groups according to risk of exposure and sex. The alkaline comet assay was used to measure DNA breaks and alkali-labile sites. We compared the mean tail moments, tail length and percentage of DNA in the tail. There was a significant difference between the control and hazard groups in DNA damage. Higher DNA damage was also found for men than for women in the control group. There was no relation of DNA damage to age either in control or hazard group. Additionally, analysis of distributions of tail moment values pointed to a considerable individual diversity even in the control group. Therefore, further investigations were necessary into the suitability of the comet assay as a biological dosimetry method; the results obtained so far warrant such investigations.

Effect of signal transduction inhibition in adapted lymphocytes: micronuclei frequency and DNA repair.

Irradiation of human lymphocytes (1 cGy X rays, 37 degrees C) or their treatment with 10 microM hydrogen peroxide (30 min at 37 degrees C) evoked a ca 30% decrease in the frequency of micronuclei upon subsequent X-irradiation (1.5 Gy). The response was reflected in a lower micronuclei frequency, but no change in DNA repair rate was observed as measured by the comet assay, directly after the challenge dose. Treatment of lymphocytes with staurosporine, an inhibitor of protein kinases, or with TMB-8, a calcium antagonist, carried out in parallel with the adaptive dose prevented the development of the adaptive response measured as micronuclei frequency. In lymphocytes that were staurosporine- or TMB-8-treated and irradiated under adaptive conditions showed that the rate of DNA repair was not changed. We conclude that treatment with agents that interfere with the transduction of the signal triggered by the low dose prevents the development of the adaptive response induced by X rays or hydrogen peroxide. Lower chromosome damage revealed by the cytokinesis block-micronuclei test in the adapted lymphocytes is unrelated to DNA repair rate as measured by comet assay.

Anti-CD38 prevents the development of the adaptive response induced by X-rays in human lymphocytes.

Irradiation of human lymphocytes (1 cGy X-rays, 37 degrees C) evoked an approximately 30% decrease in the frequency of micronuclei upon subsequent X-irradiation (1.5 Gy). The response was reflected in a lower micronucleus frequency but not in the DNA repair rate measured by the comet assay directly after the challenge dose. Treatment of lymphocytes with anti-CD38 antibody 1 h before irradiation with the adaptive dose prevented the development of the adaptive response measured as micronuclei frequency, but adaptation was not reflected in a lower rate of DNA repair, measured by the alkaline version of the 'comet' assay. In lymphocytes that were anti-CD38-treated and irradiated and or irradiated with the adaptive dose the rate of DNA repair was not changed. However, the mean DNA damage level in adapted anti-CD38-treated lymphocytes was significantly lower than that in the control lymphocytes at all time points. We conclude that ligation of CD38 by antibody initiates signalling that prevents the development of the adaptive response induced by X-rays. Lower chromosome damage revealed by the cytokinesis block-micronucleus test in the adapted lymphocytes is unrelated to DNA repair rate.

Calcium antagonist, TMB-8, prevents the induction of adaptive response by hydrogen peroxide or X-rays in human lymphocytes.

Treatment of human lymphocytes with hydrogen peroxide (10 microM, 30 min, 37 degrees C in PBS) or with 1 cGy X-rays evoked about a 30% decrease in the frequency of micronuclei upon subsequent X-irradiation (1.5 Gy). In addition to a lower micronuclei frequency, we also found an increase in the sedimentation distance of the nucleoids, when measured 90 min (duration of the isolation procedure carried out at 4 degrees C) after the adaptive dose (hydrogen peroxide or X-rays) and preceding the challenge dose. To test whether Ca2+ is involved in the induction of the adaptive response pathway, we treated cells with the calcium chelator, EGTA. When EGTA was given at the same time as the adaptive dose, it prevented the development of the adaptive response. In addition, the calcium antagonist, TMB-8, also prevented the development of the adaptive response as it prevented the reduction of both micronuclei and increased nucleoid sedimentation. Cellular treatment with TMB-8 increased the free [Ca2+] by 40%, when given together with hydrogen peroxide. The faster sedimenting nucleoids from adapted cells were also examined by ethidium bromide titration; there was no indication of any change in supercoil density or loop size. Psi-tectorigenin, an inhibitor of phosphatidylinositol turnover, did not modify the adaptive response, indicating that inositol (1,4,5)-trisphosphate is not involved in the induction of the adaptive response, but free Ca2+ ions are.

Structure-activity relationship of polyamine derivatives of 1,3-dichloroacetone-thiosemicarbazone: induction of metastases and increase in sialylation of murine lymphoma L5178Y-R cells.

A number of polyamine (PA) derivatives of thiosemicarbazone of 1,3-dichloroacetone (TDA) have been prepared and their effect on growth in vivo of tumorigenic but not metastatic cell strain (LY-R) of mouse lymphoma L5178Y has been investigated. Polyamine derivatives of TDA (PDT) were injected i.p. every third day (4 times, 10 or 25 mg/kg per injection) into DBA/2 mice inoculated i.p. or s.c. with LY-R cells. It has been found that disubstituted putrescine (Put), spermidine (Spd) and spermine (Spm) derivatives TDA exhibit a prometastatic activity as indicated by the appearance of solid tumor foci in subcutaneous tissues, liver and spleen. This activity depends mainly on the structure of the PA fragment and the presence of TDA. An increase in lipid bound sialic acid content after treating LY-R cells in vitro and in vivo with a Spm derivative has been found. These findings suggest that disubstituted PA derivatives of TDA and LY-R cells may be a useful model for investigation of the final steps in formation of metastases by lymphoma cells.

Removal of 239Pu from mice with 3,4,3 LICAM(C) or N,N',N'',N'''-tetra-(2,3-dihydroxybenzoyl)-spermine.

Male mice SAS/4 were injected i.v. with 239Pu citr(IV) 0.27 microCi . kg-1-9.99 kBq X kg-1. After 1 h 30 mumol . kg-1 of 3,4,3 LICAM(C), N,N',N'',N'''-tetra-(2,3-dihydroxybenzoyl)-spermine or Na3CaDTPA as a reference compound was given intraperitoneally. After 4 days the animals were sacrificed and the Pu content in livers, kidneys, femurs and carcasses was determined by the liquid scintillation method. It was found that, as compared with the control, 3,4,3 LICAM(C) removed 83% of the Pu activity deposited in the liver, 71% of that in the femur and 79% of the Pu in the whole body. The Pu content in the kidneys exceeded the control value by about 50%. Na3CaDTPA removed 96, 86, 40 and 72% of plutonium from the liver, kidneys, femurs and carcasses respectively. Tetra-DHB-spermine caused the excretion of 50, 57 and 39% of Pu from liver, bone and whole body respectively. The retention of Pu in the kidneys was increased to 400% of the control value.