Induction of dominant lethal mutations by gamma irradiation of Gallus domesticus spermatozoa

International Nuclear Information System (INIS)

Baumgartner, J.; Grom, A.; Csuka, J.; Kindlova, L.

1977-01-01

Mixed semen of Gallus domesticus cocks was gamma irradiated in vitro with exposures of 500, 1000, 2000 and 3000 R at the exposure rate of 5.86 Rs -1 . After the irradiation the semen was applied to experimental and control layer hens, the embryonic mortality in F 1 was observed, the total number of incubated eggs was 3344. Irradiation with 500 R had a favourable influence on embryonic vitality, the exposures 1000, 2000 and 3000 R resulted in increased embryonic mortality, for 2100 R a 50% mortality of offspring was found. Induced dominant lethality was manifest during embryonic and oviduct development. The frequency of induced dominant lethality for exposures used was 19.2, 9.9, 48.3, and 69.1%, the values of mutation rate were 0.087, 0.104, 0.659, and 1.174. The mutation rate had linear course, the value of the lethal hit per gamete for 1 R was 1.04x10 -4 . (author)

Forecasting of the lethality in cases of nonuniform accidental irradiation (experimental studies at external gamma irradiation of rats)

International Nuclear Information System (INIS)

Ingilizova, K.

1983-01-01

A model is suggested that enables the prediction of death probability for the body (L) within the whole lethality dose range (DL 0 -DL 100 ), on the basis of predetermined physical characteristics: in cases of uneven external wholebody irradiation. Some biological effects of 4 variants of uneven irradiation have been studied, i.e. ventro-dorsal (V-D), dorso-ventral (D-V), cranio-caudal (Cr-Ca) and caudo-cranial (Ca-Cr). The following basic conclusions have been drawn: 1. The study of the biological effects of uneven irradiation, when estimated by the lethality factor, points out the lower efficiency of the former, if compared to even irradiation. 2. The even irradiation lethality in the conducted experiments, according to the ALE data and the postradiation mortality dynamics, is determined basically by the damage of the bloodforming tissue and the animals die of bone marrow syndrome. 3. The uneven irradiation, estimated by the total weight factor, is of lower efficiency than the even one. 4. The radiation-induced hypoplasia of the studied organs is exponential in character. 5. An original model for predicting radiation mortality in cases of uneven irradiation has been constructed. The model gives the possibility of relating the alterations in the index of biological efficiency reduction to the wholebody irradiation factor, as well as to the two systems with highest radiosensitivity: red bone marrow and the small intestine. The model helps determining the numerical value of death probability, depending on the average body irradiation doses and the integral unevenness factors for RBM. (author)

Reproductive-phase and interphase lethal cell damage after irradiation and treatment with cytostatics

International Nuclear Information System (INIS)

Hagemann, G.

1979-01-01

After X-ray irradiation of manual cells, two lethal fractions occur due to reproductive and interphase death under low and high radiation doses. The damage kinetics on which this fact is based is compared with hypothetical tumour frequencies and leucemia induction caused in experiments. The reproductive-lethal damage can be manifested by means of colony size spectrometry, with the median colony size class differences (MCD) serving as measure for the damage found. The simultaneous effects of the cytostatics BLEOMYCIN or ICRF 159 and X-rays on reproductive lethal and interphase-lethal damage are measured by means of MCD and survival fraction, and the additive and intensifying effect' is judged with the help of suitably defined terms. This shows that the clinically used ICRF 159 has an additive effect on interphase-lethal and a sub-additive effect on reproductive-lethal cell damage. Thus, favourable results may be expected for the electivity factor in fractionated irradiation and with regard to delayed damage in healthy tissue. (orig.) 891 MG/orig. 892 RDG [de

Metabolic changes after non-lethal X-irradiation of rats. I

International Nuclear Information System (INIS)

Ahlersova, E.; Ahlers, I.; Slavkovska, E.; Praslicka, M.

1981-01-01

Male rats of the Wistar strain were fasted overnight prior to exposure to single whole-body X-ray dose of 2.39 Gy (250 R). Irradiated and sham-irradiated rats were pair-fed for 5 days, in the following period they were fed ad libitum. The levels of corticosterone and immunoreactive insulin in serum, glucose in blood, glycogen in liver, heart and skeletal muscle were determined 1 and 6 h, 1, 2, 3, 7, 14, 21, 28, and 38 days after irradiation and sham-irradiation. Irradiation of rats resulted, in one hour, in a decrease and, in two days, in an increase in blood glucose level. A marked increase in liver glycogen persisted from 6 h to 21 days after irradiation. The level of glycogen in the skeletal muscle was reduced after 6 h and increased on days 3 and 14. Heart muscle glycogen declined within the first 24 h and rose at 14 days after exposure. The kinetics of changes in the heart and skeletal muscle glycogen following non-lethal irradiation was similar and indicated an overlap of changes produced by fasting with those brought about by irradiation, particularly during the first week. Corticosterone in serum was markedly increased in rats 24 and 72 h after irradiation compared to pair-fed controls. The serum insulin concentration did not change after irradiation, except for a single increase on day 21. Irradiation with non-lethal doses produced changes in the parameters of the carbohydrate metabolism studied, except for serum insulin which reflected the changes in the nutrition regimen upon pair-feeding rather than the effect of ionizing irradiation. (author)

Anti-asialo GM1 antiserum treatment of lethally irradiated recipients before bone marrow transplantation: Evidence that recipient natural killer depletion enhances survival, engraftment, and hematopoietic recovery

International Nuclear Information System (INIS)

Tiberghien, P.; Longo, D.L.; Wine, J.W.; Alvord, W.G.; Reynolds, C.W.

1990-01-01

Natural killer (NK) cells are reported to have an important role in the resistance of lethally irradiated recipients to bone marrow transplantation (BMT). Therefore, we investigated the effects of recipient NK depletion on survival, chimerism, and hematopoietic reconstitution after lethal irradiation and the transplantation of limiting amounts of T-cell-deficient bone marrow (BM). When administered before BMT, anti-asialo GM1 (ASGM1) antiserum treatment, effective in depleting in vivo NK activity, was associated with a marked increase in survival in 3 of 3 allogeneic combinations (BALB/c into C3H/HeN, C57B1/6, or C3B6F1). This enhanced survival was independent of the susceptibility of each recipient strain to accept BALB/c BM. Moreover, recipient anti-ASGM1 treatment was also effective in increasing survival in recipients of syngeneic BM, suggesting that NK cells can adversely affect engraftment independent of genetically controlled polymorphic cell surface determinants. Analysis of chimerism in surviving animals 2 months post-BMT showed that recipient NK depletion significantly increased the level of donor engraftment when high doses of BM were transplanted. These studies also demonstrated that anti-ASGM1 pretreatment mainly resulted in an increase in extramedullary hematopoiesis in the second and third week after irradiation. Anti-ASGM1 treatment also dramatically accelerated the rate of appearance of donor-derived cells with a higher level of donor-cell engraftment apparent at a time when the differences in survival between NK-depleted and control BMT recipients became significant. Peripheral cell counts were also affected by NK depletion, with significantly enhanced platelet and red blood cell recovery and a moderate increase in granulocyte recovery

Anti-asialo GM1 antiserum treatment of lethally irradiated recipients before bone marrow transplantation: Evidence that recipient natural killer depletion enhances survival, engraftment, and hematopoietic recovery

Energy Technology Data Exchange (ETDEWEB)

Tiberghien, P.; Longo, D.L.; Wine, J.W.; Alvord, W.G.; Reynolds, C.W. (Program Resources, Inc., Frederick, MD (USA))

1990-10-01

Natural killer (NK) cells are reported to have an important role in the resistance of lethally irradiated recipients to bone marrow transplantation (BMT). Therefore, we investigated the effects of recipient NK depletion on survival, chimerism, and hematopoietic reconstitution after lethal irradiation and the transplantation of limiting amounts of T-cell-deficient bone marrow (BM). When administered before BMT, anti-asialo GM1 (ASGM1) antiserum treatment, effective in depleting in vivo NK activity, was associated with a marked increase in survival in 3 of 3 allogeneic combinations (BALB/c into C3H/HeN, C57B1/6, or C3B6F1). This enhanced survival was independent of the susceptibility of each recipient strain to accept BALB/c BM. Moreover, recipient anti-ASGM1 treatment was also effective in increasing survival in recipients of syngeneic BM, suggesting that NK cells can adversely affect engraftment independent of genetically controlled polymorphic cell surface determinants. Analysis of chimerism in surviving animals 2 months post-BMT showed that recipient NK depletion significantly increased the level of donor engraftment when high doses of BM were transplanted. These studies also demonstrated that anti-ASGM1 pretreatment mainly resulted in an increase in extramedullary hematopoiesis in the second and third week after irradiation. Anti-ASGM1 treatment also dramatically accelerated the rate of appearance of donor-derived cells with a higher level of donor-cell engraftment apparent at a time when the differences in survival between NK-depleted and control BMT recipients became significant. Peripheral cell counts were also affected by NK depletion, with significantly enhanced platelet and red blood cell recovery and a moderate increase in granulocyte recovery.

Transient engraftment of syngeneic bone marrow after conditioning with high-dose cyclophosphamide and thoracoabdominal irradiation in a patient with aplastic anemia

International Nuclear Information System (INIS)

Matsue, K.; Niki, T.; Shiobara, S.; Ueda, M.; Ohtake, S.; Mori, T.; Matsuda, T.; Harada, M.

1990-01-01

We describe the clinical course of a 16 year old girl with aplastic anemia who was treated by syngeneic bone marrow transplantation. Engraftment was not obtained by simple infusion of bone marrow without immunosuppression. The patient received a high-dose cyclophosphamide and thoracoabdominal irradiation, followed by second marrow transplantation from the same donor. Incomplete but significant hematologic recovery was observed; however, marrow failure recurred 5 months after transplantation. Since donor and recipient pairs were genotypically identical, graft failure could not be attributed to immunological reactivity of recipient cells to donor non-HLA antigens. This case report implies that graft failure in some cases of aplastic anemia might be mediated by inhibitory cells resistant to cyclophosphamide and irradiation

Photoreactivable sector of lethal damage in ultraviolet-irradiated Escherichia coli cells

International Nuclear Information System (INIS)

Balgavy, P.

1976-01-01

The photoreactivable sector of lethal damage in Escherichia coli Bsub(s-1), Escherichia coli B/r Hcr - and Escherichia coli B/r Hcr + cells after ultraviolet irradiation at 254 nm is 0.823 +- 0.004, 0.70 +- 0.01 and 0.53 +- 0.06, respectively, at 99% confidence limits. For the low values of the photoreactivable sector in the B/r Hcr - and B/r Hcr + strains are likely to be responsible dark repair processes which eliminate lethal damage, brought about by pyrimidine dimers, preferably in comparison with lethal damage caused by photoproducts of another type. (author)

Induction of tolerance and prolongation of islet allograft survival by syngeneic hematopoietic stem cell transplantation in mice.

Science.gov (United States)

Yang, Shi-feng; Xue, Wu-jun; Lu, Wan-hong; Xie, Li-yi; Yin, Ai-ping; Zheng, Jin; Sun, Ji-ping; Li, Yang

2015-10-01

Syngeneic or autologous hematopoietic stem cells transplantation (HSCT) has been proposed to treat autoimmune diseases because of its immunosuppressive and immunomodulatory effects, which can also contribute to posttransplant antirejection therapy. In this study, we explored the tolerogenic effect of syngeneic HSCT on prolonging islet allograft survival. C57BL/6 mice received syngeneic HSCT plus preconditioning with sublethal irradiation. Then islets of BALB/c mice were transplanted into the renal subcapsular of C57BL/6 mice after chemically induced into diabetes. HSCT mice exhibited improved islet allograft survival and increased serum insulin compared to control mice. Islet allografts of HSCT mice displayed lower level lymphocyte infiltration and stronger insulin staining than control mice. T cells of HSCT mice proliferated poorly in response to allogeneic splenocytes compared to control mice. Mice appeared reversed interferon-γ (IFN-γ)/interleukin-4 (IL-4) ratio to a Th2 immune deviation after syngeneic HSCT. The percentage of CD8(+) T cells was lower, while percentage of CD4(+)CD25(+)Foxp3(+) T regulatory cells (Tregs) was higher in HSCT mice than control mice. HSCT mice showed higher percentage of CTLA-4(+) T cells and expression of CTLA-4 mRNA than control mice. Targeting of CTLA-4 by intraperitoneal injection of anti-CTLA-4 mAb abrogated the effect of syngeneic HSCT on prolonging islet allograft survival, inhibiting activity of T cells in response to alloantigen, promoting Th1 to Th2 immune deviation and up regulating CD4(+)CD25(+)Foxp3(+) Tregs. Syngeneic HSCT plus preconditioning of sublethal irradiation induces tolerance and improves islet allograft survival in fully mismatched mice model. Th1 to Th2 immune deviation, increased CD4(+)CD25(+)Foxp3(+) Tregs and up-regulation of CTLA-4 maybe contribute to the tolerogenic effect induced by syngeneic HSCT. Copyright © 2015 Elsevier B.V. All rights reserved.

Clinical and symptomatological study of pigs subjected to a lethal dose of integral gamma irradiation

International Nuclear Information System (INIS)

Vaiman, M.; Guenet, J.-L.; Maas, J.; Nizza, P.

1966-05-01

Results are reported from a clinical and haematological study on a Corsican species of pigs wholly exposed to an approximately lethal dose of γ radiation. The aim of this work was to examine the changes in the irradiation syndrome of irradiation for pigs to make it thus possible to devise further experiments, in particular in the therapeutic field. The dose received was 285 rads (measured as the absorption in the vertical antero-posterior medial plane). Data are presented on cyto-haematological changes in the blood circulating immediately after irradiation, and followed up to death, and changes in the medullary cytology after irradiation. The clinical picture of lethal radiation injury in swine is described. (authors) [fr

Mutagenicity assayed by dominant lethality testing in mice fed a combined gamma-irradiated diet

International Nuclear Information System (INIS)

Rupova, I.; Katsarova, Ts.; Bajrakova, A.; Baev, I.; Tencheva, S.

1980-01-01

Mice fed a combined gamma-irradiated diet were examined for a mutagenic effect using the dominant lethality test. Their feed contained the following irradiated ingredients: 20% maize, 10% dried plums, and 5% walnut kernels. Taking into account cycle duration in spermatogenesis and oogenesis, males were fed this special diet throughout 56 days, and females throughout 21 days. The experiments involved three animal groups: (1) fed the special diet containing irradiated ingredients; (2) fed the special diet but with the ingredients nonirradiated; and (3) fed standard vivarium diet. Matings to provide the first generation were between one parent fed the special diet and a partner fed standard diet. With an adequate number of implants examined on day 16 of gestation, embryonic death rate was not found to be increased; hence, induction of dominant lethality from consumption of irradiated diet failed to be demonstrated

Restoring efficiency of hemopoietic cell transplantation in a mouse lethally irradiated by a total exposure to X rays

International Nuclear Information System (INIS)

Doria, Gino

1959-10-01

This research thesis reports the study of possibility of treatments (or restoration) of a mouse which has been submitted to a lethal dose of X rays. More particularly, the author compared the restoring efficiency of bone marrow and fetal liver injected in a mouse which had been lethally irradiated by a total exposure to X rays. He also studied the functional status of the hemopoietic graft, and the emergence of the secondary disease in mice which had been as well lethally irradiated and then restored by injection of bone marrow and fetal liver. The author then addressed the influence of the induction of immune tolerance of the host with respect to the donor on the survival of a mouse lethally irradiated and restored by homologue bone marrow [fr

Caffeine protects mice against whole-body lethal dose of {gamma}-irradiation

Energy Technology Data Exchange (ETDEWEB)

George, K.C.; Hebbar, S.A.; Kale, S.P.; Kesavan, P.C. [Biosciences Group, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

1999-06-01

Administration of caffeine (1,3,7-trimethylxanthine), a major component of coffee, to Swiss mice at doses of 80 or 100 mg/kg body weight 60 min prior to whole-body lethal dose of {gamma}-irradiation (7.5 Gy) resulted in the survival of 70 and 63% of animals, respectively, at the above doses in contrast to absolutely no survivors (LD-100/25 days) in the group exposed to radiation alone. Pre-treatment with a lower concentration of caffeine (50 mg/kg) did not confer any radioprotection. The protection exerted by caffeine (80 mg/kg), however, was reduced from 70 to 50% if administered 30 min prior to irradiation. The trend statistics reveal that a dose of 80 mg/kg administered 60 min before whole-body exposure to 7.5 Gy is optimal for maximal radioprotection. However, caffeine (80 mg/kg) administered within 3 min after irradiation offered no protection. While there is documentation in the literature that caffeine is an antioxidant and radioprotector against the toxic pathway of radiation damage in a wide range of cells and organisms, this is the first report demonstrating unequivocally its potent radioprotective action in terms of survival of lethally whole-body irradiated mice. (author)

Inhibitory action of chlorophyllin of autosome recessive lethals induced by irradiation

International Nuclear Information System (INIS)

Salceda, V.M.; Pimentel, P.A.E.; Cruces, M.P.

2006-01-01

The chlorophyllin is a sodium salt of the chlorophyll that has a strong protective action of the damage induced by different agents so much physical as chemical. In Drosophila there is reported this effect in somatic cells. In contrast, in germinal cells using tests with the sexual chromosomes has not been found such inhibitory action. For this reason, in this occasion we will refer to the effect of the lethality induced in autosome chromosomes, in particular to the chromosome II of this species. For such effect groups of males of the line Canton-S its were pre-treated for 24h with or without 69 mm of CCS and later on treaties with or without 40 Gy of gamma irradiation. The males were then subjected to the technical Cy L / Pm for the detection of recessive lethals. In the third generation the respective counts of the descendant of each one of them to determine the corresponding categories for each extracted chromosome were made. To be mendelian crosses it is expected for a normal chromosome a proportion 2:1 of individuals with genotype Cy L / +: +/+. The absence of individuals +/+ it is indicative of a lethal gene, until 10% of these individuals of each male's total descendant, it is considered that is carrying of a semi lethal gene. The sum of lethal and semi lethals constitutes the category detrimental. The obtained results indicated that the pre-treatment with CCS reduces in a significant way the frequency of induced lethals by 40 Gy of gamma rays. The fact that an effect inhibitor has not been observed in the test of recessive lethal bound to the sex obtained previously, it contrasts with the effect observed in the chromosome II, results of this study and with the one observed in the chromosome III in somatic cells. The above-mentioned shows a differential action of the CCS between sexual chromosomes and autosomal before the effect of the gamma radiation. At the moment we don't have an explanation to these evidences. To evaluate the action of the chlorophyllin

Arrest of irradiated G1, S, or G2 cells at mitosis using nocodazole promotes repair of potentially lethal damage

International Nuclear Information System (INIS)

Iliakis, G.; Nuesse, M.

1984-01-01

The ability of synchronized Ehrlich ascites tumor cells, irradiated in G1, S, and G2 phases, to repair potentially lethal damage when arrested at mitosis by using 0.4 μg/ml nocodazole, a specific inhibitor of microtubule polymerization, has been studied. Cells irradiated in these phases were found to repair potentially lethal damage at mitosis. The extent of this repair was similar to that observed for cells irradiated at the same stages in the cell cycle but allowed to repair potentially lethal damage by incubating in balanced salt solution for 6 hr after X irradiation

The nature of tolerance in adult recipient mice made tolerant of alloantigens with supralethal irradiation followed by syngeneic bone marrow cell transplantation plus injection of F1 spleen cells

International Nuclear Information System (INIS)

Tomita, Y.; Himeno, K.; Mayumi, H.; Tokuda, N.; Nomoto, K.

1989-01-01

The length of time after syngeneic bone marrow reconstitution when tolerance to alloantigens can be induced in adult mice during T cell differentiation from bone marrow cells was studied by exposing those T cells to (recipient x donor)F1 spleen cells. Supralethally irradiated C3H/He Slc(C3H; H-2k) mice were reconstituted with 1 x 10(7) syngeneic T cell-depleted bone marrow cells and then injected intravenously with 5 x 10(7) (C3H x C57BL/6[B6])F1 (B6C3F1; H-2bxk) or (C3H x AKR/J[AKR])F1 (AKC3F1; H-2kxk) spleen cells at various intervals. In the fully allogeneic combination of B6C3F1----C3H, EL-4 tumor originating from B6 was accepted, and survival of grafted B6 skin was significantly prolonged in the tolerant C3H mice treated with irradiation on day -1 followed by injection of syngeneic bone marrow cells on day 0 plus B6C3F1 spleen cells on days 0, 5, or 10, in a tolerogen-specific manner. In the multiminor histocompatibility antigen-disparate combination of AKC3F1----C3H, AKR skin grafts were permanently accepted in the tolerant C3H mice treated with AKC3F1 spleen cells on days 0, 5, 10, or 15. Immunological parameters, including cytotoxic T lymphocyte activity and delayed foot-pad reaction (DFR), were almost completely suppressed in C3H mice made tolerant of B6 or AKR antigens. A chimeric assay using a direct immunofluorescence method revealed that the tolerant C3H mice given B6C3F1 spleen cells on day 0 were mixed-chimeric for at least 8 weeks after syngeneic bone marrow reconstitution, but not definitely chimeric thereafter. The C3H mice given AKC3F1 spleen cells on day 0 were chimeric even 43 weeks after syngeneic bone marrow reconstitution, but the C3H mice given AKC3F1 spleen cells on day 15 showed temporal chimerism that disappeared within 43 weeks. The untolerant mice were never detectably chimeric

Transplantation of bone marrow cells into lethally irradiated mice

International Nuclear Information System (INIS)

Viktora, L.; Hermanova, E.

1978-01-01

Morphological changes were studied of megakaryocytes in the bone marrow and spleen of lethally irradiated mice (0.2 C/kg) after transplantation of living bone marrow cells. It was observed that functional trombopoietic megakaryocytes occur from day 15 after transplantation and that functional active megakaryocytes predominate in bone marrow and spleen from day 20. In addition, other types of cells, primarily granulocytes, were detected in some megakaryocytes. (author)

Gastrointestinal decontamination in healthy and lethally irradiated monkeys

International Nuclear Information System (INIS)

Hendriks, W.D.H.

1980-01-01

In periods of extreme immunosuppression, infections which are often life-threatening, frequently occur. In an attempt to prevent such infections in lethally irradiated rhesus monkeys, the animals were subjected to strict reverse isolation prior to irradiation and administrated orally with nonabsorbable antibiotics in order to eliminate their microflora. The antibiotic combination was selected on the basis of a sensitivity test and was added to the liquid food supply. To rapidly achieve a high bactericidal concentration in the intestine, the same antibiotics were additionally given orally for 5 days. The microflora was reduced rapidly; within a few days sterile cultures were obtained. Particularly after discontinuation of the administration of the additional antibiotics were colonizations found. In contrast to colonizations persisting from the first day of treatment on, the first were rather easy to suppress. (Auth.)

Genotoxicity test of irradiated spice mixture by dominant lethal test

Energy Technology Data Exchange (ETDEWEB)

Barna, J

1986-03-01

Dominant lethal test (DLT) was performed in Sprague Dawley male rats prefed with 25% irradiated spice mixture which was composed of 55% non-pungent ground paprika, 14% black pepper, 9% allspice, 9% coriander, 7% marjoram, 4% cumin, 2% nutmeg. Microbial count of the spice mixture was reduced with 15 kGy from a sup(60)Co source. Control groups received spice-free or untreated spice diet or were administered to cyclophosphamide i.p., respectively. DTL parameters altered significantly in the latter group but neither untreated nor irradiated spice mixture proved to be germ cell mutagens. 24 refs.; 8 figs.

Determination the lethal dose of ascaris lumbricoides ova by gamma irradiation

International Nuclear Information System (INIS)

Shamma, M.; Al-Adawi, M.; Sharabi, N.

2002-11-01

The lethal gamma irradiation dose of ascaris lumbricoides which collected from Damascus Sewage water Plant was determined. Ascaris lumbricoides ova were treated with several gamma irradiation doses with (0.1, 0.2, 0.3, 0.4,...and 1.5 KGy). No morphological changes were observed on the eggs when directly examined microscopically after irradiation. However after two weeks of incubation at 37 degree centigrade the cell contents of the eggs which irradiated with 0.5 KGy and beyond were fragmented and scattered in the whole eggs and no larvae were observed after eight weeks of incubation. It is concluded that the dose 0.5 my be considered as the dose of choice if sewage water is to be treated by gamma rays. (author)

Determination the lethal dose of ascaris lumbricoides ova by gamma irradiation

CERN Document Server

Shamma, M A; Sharabi, N

2002-01-01

The lethal gamma irradiation dose of ascaris lumbricoides which collected from Damascus Sewage water Plant was determined. Ascaris lumbricoides ova were treated with several gamma irradiation doses with (0.1, 0.2, 0.3, 0.4,...and 1.5 KGy). No morphological changes were observed on the eggs when directly examined microscopically after irradiation. However after two weeks of incubation at 37 degree centigrade the cell contents of the eggs which irradiated with 0.5 KGy and beyond were fragmented and scattered in the whole eggs and no larvae were observed after eight weeks of incubation. It is concluded that the dose 0.5 my be considered as the dose of choice if sewage water is to be treated by gamma rays.

Effects of lethal dose of γ-irradiation on intestinal enzymes of the pigeons Columba livia intermedia Strickland

International Nuclear Information System (INIS)

Gadhia, P.K.

1979-01-01

Effect of γ-irradiation with lethal dose (1000 rads) on alkaline phosphatase and glucose-6-phosphatase have been studied in two different regions (duodenum and ileum) of small intestine of pigeons. The enzymes were studied at different intervals like 2, 4, 6 and 8 days after irradiation. The sp. activities of enzyme increased significantly both in duodenum and ileum. However, significant increase in alkaline phosphatase and glucose-6-phosphatase were observed at the 2nd and the 4th days post-irradiation respectively. The increase in enzyme activities may present de novo synthesis of these enzymes after lethal dose of irradiation. The histologic picture revealed that after the 4th day of irradiation, the number of goblet cells increased and after the 6th day crypt-villus system was destroyed completely as compared to sham-irradiated pigeons. (author)

Effects of lethal dose of. gamma. -irradiation on intestinal enzymes of the pigeons Columba livia intermedia Strickland

Energy Technology Data Exchange (ETDEWEB)

Gadhia, P.K. (South Gujarat Univ., Surat (India). Dept. of Biosciences); Shah, V.C. (Gujarat Univ. School of Sciences, Ahmedabad (India))

1979-09-01

Effect of ..gamma..-irradiation with lethal dose (1000 rads) on alkaline phosphatase and glucose-6-phosphatase have been studied in two different regions (duodenum and ileum) of small intestine of pigeons. The enzymes were studied at different intervals like 2, 4, 6 and 8 days after irradiation. The sp. activities of enzyme increased significantly both in duodenum and ileum. However, significant increase in alkaline phosphatase and glucose-6-phosphatase were observed at the 2nd and the 4th days post-irradiation respectively. The increase in enzyme activities may present de novo synthesis of these enzymes after lethal dose of irradiation. The histologic picture revealed that after the 4th day of irradiation, the number of goblet cells increased and after the 6th day crypt-villus system was destroyed completely as compared to sham-irradiated pigeons.

Soluble factor(s) from bone marrow cells can rescue lethally irradiated mice by protecting endogenous hematopoietic stem cells.

Science.gov (United States)

Zhao, Yi; Zhan, Yuxia; Burke, Kathleen A; Anderson, W French

2005-04-01

Ionizing radiation-induced myeloablation can be rescued via bone marrow transplantation (BMT) or administration of cytokines if given within 2 hours after radiation exposure. There is no evidence for the existence of soluble factors that can rescue an animal after a lethal dose of radiation when administered several hours postradiation. We established a system that could test the possibility for the existence of soluble factors that could be used more than 2 hours postirradiation to rescue animals. Animals with an implanted TheraCyte immunoisolation device (TID) received lethal-dose radiation and then normal bone marrow Lin- cells were loaded into the device (thereby preventing direct interaction between donor and recipient cells). Animal survival was evaluated and stem cell activity was tested with secondary bone marrow transplantation and flow cytometry analysis. Donor cell gene expression of five antiapoptotic cytokines was examined. Bone marrow Lin- cells rescued lethally irradiated animals via soluble factor(s). Bone marrow cells from the rescued animals can rescue and repopulate secondary lethally irradiated animals. Within the first 6 hours post-lethal-dose radiation, there is no significant change of gene expression of the known radioprotective factors TPO, SCF, IL-3, Flt-3 ligand, and SDF-1. Hematopoietic stem cells can be protected in lethally irradiated animals by soluble factors produced by bone marrow Lin- cells.

Evaluation of freshly irradiated wheat for dominant lethal mutations in Wistar rats

International Nuclear Information System (INIS)

Pawan, S.C.; Aravindakshan, M.; Kumar, N.S.; Subba Rao, V.; Aiyar, A.S.; Sundaram, K.

1977-01-01

Three independent, serially performed experiments involving acute and chronic feeding of freshly irradiated wheat (75 krad, gamma-irradiation) were carried out in Wistar rats. In the first experiment groups of 10 males were given wheat for 1 week; irradiated wheat was consumed by the animals within 24 h of irradiation. In the other two experiments feeding of males was continued for 6 (10 males per group) and 12 (13 males per group) weeks, respectively, and the irradiated wheat was fed within 7 days of irradiation. At the end of each treatment period each male was paired with 3 females for 7 days and sequentially at weekly intervals for 5 or 8 weeks. Females were killed and examined for live and dead implantations and corpora lutea. There were no differences between groups with regard to fertility nor was there any inter-group difference as regards pre- and post-implantation losses whether the rats were fed irradiated or non-irradiated wheat. This suggested that even feeding of freshly irradiated wheat does not induce any dominant lethal mutations in rats

Evaluation of freshly irradiated wheat for dominant lethal mutations in Wistar rats

Energy Technology Data Exchange (ETDEWEB)

Pawan, S C; Aravindakshan, M; Kumar, N S; Subba Rao, V; Aiyar, A S; Sundaram, K [Bhabha Atomic Research Centre, Bombay (India). Bio-medical Group

1977-01-01

Three independent, serially performed experiments involving acute and chronic feeding of freshly irradiated wheat (75 krad, gamma-irradiation) were carried out in Wistar rats. In the first experiment groups of 10 males were given wheat for 1 week; irradiated wheat was consumed by the animals within 24 h of irradiation. In the other two experiments feeding of males was continued for 6 (10 males per group) and 12 (13 males per group) weeks, respectively, and the irradiated wheat was fed within 7 days of irradiation. At the end of each treatment period each male was paired with 3 females for 7 days and sequentially at weekly intervals for 5 or 8 weeks. Females were killed and examined for live and dead implantations and corpora lutea. There were no differences between groups with regard to fertility nor was there any inter-group difference as regards pre- and post-implantation losses whether the rats were fed irradiated or non-irradiated wheat. This suggested that even feeding of freshly irradiated wheat does not induce any dominant lethal mutations in rats.

Comparative influence of dose rate and radiation nature, on lethality after big mammals irradiation

International Nuclear Information System (INIS)

Destombe, C.; Le Fleche, Ph.; Grasseau, A.; Reynal, A.

1997-01-01

For the same dose and the 30 days lethality as biological criterion, the dose rate influence is more important than the radiation nature on the results of an big mammals total body irradiation. (authors)

Increased incidence of murine graft-versus-host disease after allogeneic bone marrow transplantation by previous infusion of syngeneic bone marrow cells

International Nuclear Information System (INIS)

Waer, M.; Ang, K.K.; van der Schueren, E.; Vandeputte, M.

1984-01-01

Different groups of BALB/c mice received supralethal total-body irradiation (TBI; 8.5 Gy, day 0). When 30 x 10(6) allogeneic (C57B1) bone marrow (BM) cells were infused with or without 10 x 10(6) syngeneic (BALB/c) bM cells on day 1, many animals (60%) died from graft-versus-host disease (GVHD). Typing of peripheral blood leukocytes for donor antigens showed that, respectively, 22/22 and 17/21 of the mice in both groups became chimeric. When syngeneic bone marrow was given on day 1 and allogeneic bone marrow on day 2 after TBI, a similar number of animals (21/23) became chimeric, but GVHD occurred more frequently in this group (25/26 mice, P less than 0.01). When the syngeneic bone marrow cells were replaced by spleen cells, or when the transplantation of allogeneic bone marrow was delayed till days 3 or 6 after TBI, almost all mice rejected the allogeneic BM graft and became long-term survivors. BALB/c mice receiving 30 x 10(6) C57B1 BM cells after 17 daily fractions of 0.2 Gy of total lymphoid irradiation (TLI), showed a high incidence of chimerism (15/17) and in none of the latter animals was GVHD observed. Despite the high incidence of GVHD in the mice receiving allogeneic BM after TBI and syngeneic BM transplantation, as compared with mice prepared with TLI which do not develop GVHD, suppressor cells were as easily induced after TBI and syngeneic BM transplantation as after TLI

Insulin-Like Growth Factor 1 Mitigates Hematopoietic Toxicity After Lethal Total Body Irradiation

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Zhou, Dunhua; Deoliveira, Divino; Kang, Yubin; Choi, Seung S. [Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States); Li, Zhiguo [Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, North Carolina (United States); Chao, Nelson J. [Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States); Department of Pathology, Duke University Medical Center, Durham, North Carolina (United States); Department of Immunology, Duke University Medical Center, Durham, North Carolina (United States); Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina (United States); Chen, Benny J., E-mail: chen0032@mc.duke.edu [Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina (United States); Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States)

2013-03-15

Purpose: To investigate whether and how insulin-like growth factor 1 (IGF-1) mitigates hematopoietic toxicity after total body irradiation. Methods and Materials: BALB/c mice were irradiated with a lethal dose of radiation (7.5 Gy) and treated with IGF-1 at a dose of 100 μg/dose intravenously once a day for 5 consecutive days starting within 1 hour after exposure. Survival and hematopoietic recovery were monitored. The mechanisms by which IGF-1 promotes hematopoietic recovery were also studied by use of an in vitro culture system. Results: IGF-1 protected 8 of 20 mice (40%) from lethal irradiation, whereas only 2 of 20 mice (10%) in the saline control group survived for more than 100 days after irradiation. A single dose of IGF-1 (500 μg) was as effective as daily dosing for 5 days. Positive effects were noted even when the initiation of treatment was delayed as long as 6 hours after irradiation. In comparison with the saline control group, treatment with IGF-1 significantly accelerated the recovery of both platelets and red blood cells in peripheral blood, total cell numbers, hematopoietic stem cells, and progenitor cells in the bone marrow when measured at day 14 after irradiation. IGF-1 protected both hematopoietic stem cells and progenitor cells from radiation-induced apoptosis and cell death. In addition, IGF-1 was able to facilitate the proliferation and differentiation of nonirradiated and irradiated hematopoietic progenitor cells. Conclusions: IGF-1 mitigates radiation-induced hematopoietic toxicity through protecting hematopoietic stem cells and progenitor cells from apoptosis and enhancing proliferation and differentiation of the surviving hematopoietic progenitor cells.

Insulin-Like Growth Factor 1 Mitigates Hematopoietic Toxicity After Lethal Total Body Irradiation

International Nuclear Information System (INIS)

Zhou, Dunhua; Deoliveira, Divino; Kang, Yubin; Choi, Seung S.; Li, Zhiguo; Chao, Nelson J.; Chen, Benny J.

2013-01-01

Purpose: To investigate whether and how insulin-like growth factor 1 (IGF-1) mitigates hematopoietic toxicity after total body irradiation. Methods and Materials: BALB/c mice were irradiated with a lethal dose of radiation (7.5 Gy) and treated with IGF-1 at a dose of 100 μg/dose intravenously once a day for 5 consecutive days starting within 1 hour after exposure. Survival and hematopoietic recovery were monitored. The mechanisms by which IGF-1 promotes hematopoietic recovery were also studied by use of an in vitro culture system. Results: IGF-1 protected 8 of 20 mice (40%) from lethal irradiation, whereas only 2 of 20 mice (10%) in the saline control group survived for more than 100 days after irradiation. A single dose of IGF-1 (500 μg) was as effective as daily dosing for 5 days. Positive effects were noted even when the initiation of treatment was delayed as long as 6 hours after irradiation. In comparison with the saline control group, treatment with IGF-1 significantly accelerated the recovery of both platelets and red blood cells in peripheral blood, total cell numbers, hematopoietic stem cells, and progenitor cells in the bone marrow when measured at day 14 after irradiation. IGF-1 protected both hematopoietic stem cells and progenitor cells from radiation-induced apoptosis and cell death. In addition, IGF-1 was able to facilitate the proliferation and differentiation of nonirradiated and irradiated hematopoietic progenitor cells. Conclusions: IGF-1 mitigates radiation-induced hematopoietic toxicity through protecting hematopoietic stem cells and progenitor cells from apoptosis and enhancing proliferation and differentiation of the surviving hematopoietic progenitor cells

Transplantation of homologous bone marrow cells to lethally irradiated mice: changes in the spleen

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Viktora, L; Hach, P; Zoubkova, M

1975-01-01

Bone marrow cell suspensions were administered intravenously to lethally irradiated mice. The number of colonies in the spleen and the regeneration of hematopoietic tissue in the spleen were studied on the 9th day after irradiation and transplantation. From a comparison of the histological picture and weight of the spleens, the authors conclude that the degree of regeneration of hematopoiesis in the spleen after irradiation and transplantation is reflected in the weight of the spleen as well as in the number of hematopoietic colonies.

Radioprotective effect of chitosan in sub-lethally X-ray irradiated mice

Energy Technology Data Exchange (ETDEWEB)

Nishimura, Yoshikazu; Ikota, Nobuo; Arima, Hiromi; Watanabe, Yoshito; Yukawa, Masae; Ozawa, Toshihiko [National Inst. of Radiological Sciences, Chiba (Japan); Kim, Hee-Sun [Korea Hydro and Nuclear Power Corp., Seoul (Korea, Republic of). Radiation Health Research Inst.; Bom, Hee-Seung; Kim, Young-Ho [Chonnam Univ., Kwangju (Korea, Republic of). Hospital

2003-03-01

The radioprotective effect of chitosan was studied in mice following whole-body X-ray irradiation. C3H/He mice were exposed to 7 Gy, and their survival rates were examined. The survival rates of chitosan-diet mice were about 20% higher than those of mice on a standard diet, and the rates dropped sharply to a plateau at day 10 after X-ray irradiation. The chitosan-diet mice had an increased weight ratio of spleen to body within the experimental period. The leukocyte, thrombocyte, and erythrocyte counts as well as the hematocrit and hemoglobin levels were recovered significantly and more rapidly in the chitosan-diet mice than the standard-diet mice at day 14 after irradiation. The scavenging abilities of chitosan were evaluated by the electron spin resonance (ESR) spin-trapping method. These observations suggested that chitosan led to hematopoetic activation and leuko-cytogenesis in mice after sub-lethal dose irradiation, and that the biological response might be caused by radical trapping or scavenging. (author)

Syngeneic transplantation in aplastic anemia

DEFF Research Database (Denmark)

Gerull, Sabine; Stern, Martin; Apperley, Jane

2013-01-01

Aplastic anemia is usually treated with immunosuppression or allogeneic transplant, depending on patient and disease characteristics. Syngeneic transplant offers a rare treatment opportunity with minimal transplant-related mortality, and offers an insight into disease mechanisms. We present here...... a retrospective analysis of all syngeneic transplants for aplastic anemia reported to the European Group for Blood and Marrow Transplantation. Between 1976 and 2009, 88 patients received 113 transplants. Most transplants (n=85) were preceded by a conditioning regimen, 22 of these including anti-thymocyte globulin...

Metabolic changes after non-lethal X-irradiation of rats. II

International Nuclear Information System (INIS)

Ahlers, I.; Ahlersova, E.; Sedlakova, A.; Praslicka, M.

1981-01-01

Male rats of the Wistar strain were subjected to whole-body X-irradiation with 2.39 Gy (250 R) and after irradiation they were pair-fed with the sham-irradiated control group. One, 6 and 24 h, 2, 3, 7, 14, 21, 28, and 38 days after exposure the animals were sacrificed and examined for serum and some tissue lipids. In the first hours an increase in lipolysis in the white adipose tissue and accumulation of non-esterified fatty acids and triacylglycerols (TG) in the liver predominated; phospholipid level increased in serum and liver and decreased in bone marrow and thymus. The later phase was characterized by hypertriacylglycerolaemia and a transient hypercholesterolaemia; accumulation of TG in bone marrow was the most important change, however. Changes in the lipid composition of the serum and tissues, except for an increase in TG level in thymus, returned to normal levels at the end of the observation period. Pair-feeding provided an equivalent nutritional situation in irradiated and sham-irradiated animals and thus eliminated the non-specific changes caused by different levels of food intake in both groups of animals, especially in the initial period. A sufficiently long observation period is necessary for estimating the kinetics of metabolic changes in rats exposed to non-lethal doses of X-irradiation. (author)

Aberrations of holokinetic chromosomes and associated lethality after X-irradiation of meiotic stages in Tetranychus urticae Koch (acari, tetranychidae)

International Nuclear Information System (INIS)

Tempelaar, M.J.

1979-01-01

Chromosomes of the holokinetic organization type were irradiated with X-rays in various stages of meiosis in unfertillized eggs of Tetranychus urticae Koch. Visible cytological aberrations, lethality and sterility were investigated in subsequent generations. Chromosome fragments are the most frequently occuring light-microscopically visible chromosome aberrations; bridges are not formed. Contrary to expectations, the presence of fragments appears to be positively correlated with the occurrence of lethality; loss of fragments, missegregation and the measure of damage of the broken chromosome parts are involved. In contrast with monokinetic chromosomes the earliest lethality occurs only after about 10 divisions. The ratios between different embryonic lethality types (early vs. late) differ depending on the stage irradiated: in more compact chromatin, more serious damage (i.e. more early lethality syndromes) is induced than in less compact chromatin. In the progeny of the surviving males, neither translocations nor independent fragments are found; indirect evidence indicated the occasional presence of inversions. The presumtive inversions are induced more frequently in a chromatin-compact stage (metaphase I) than in a less compact one (telophase I). (Auth.)

Therapeutic use of recombinant human G-CSF (rhG-CSF) in a canine model of sublethal and lethal whole-body irradiation

International Nuclear Information System (INIS)

MacVittie, T.J.; Monroy, R.L.; Patchen, M.L.; Souza, L.M.

1990-01-01

Recombinant human G-CSF (rhG-CSF) was studied for its ability to modulate haemopoiesis in normal dogs as well as to decrease therapeutically the severity and duration of neutropenia in sublethally and lethally irradiated dogs. Data indicate that in the lethally irradiated dog, effective cytokine therapy with rhG-CSF will increase survival through the induction of earlier recovery of neutrophils and platelets. (author)

Studies on chromosomal aberrations and dominant lethal mutations induced by x irradiation in germ cells of male mice

International Nuclear Information System (INIS)

Wang Xianli; Wang Mingdong; Wang Bin; Sun Shuqing

1992-01-01

After male mice irradiated by 2 Gy X rays mated to normal virginal females superovulated with PMSG and HCG, pronuclei chromosome spreading of first-cleavage embryos were prepared and chromosomal aberrations of paternal pronuclei were observed. The results showed that the frequency of chromosomal aberrations was highest irradiated at spermatic stage among different stages of spermatogenesis. The sequence of radiosensitivity in spermatogenesis was as follows: spermatids > mature sperm > spermatocyte > spermatogonia and stem spermatogonia. The frequencies of paternal chromosomal aberrations resulted from irradiation at spermatids and mature sperms were significantly higher than that in control. The reciprocal translocations of stem spermatogonia induced by 2 Gy X rays in those male mice were also examined in the preparations of diakinesis-metaphase I. The frequency of reciprocal translocations were 0.0429 per cell and significantly higher than that in control. The proportion of unbalanced gametes, resulting in lethal embryos after fertilization, was 0.02145 to be predicted. At the same time, the dominant lethality induced by X rays in stem spermatogonia was measured, being 0.0371. The frequency of dead fetuses in irradiation group was about twice as in control. The regression analysis was found that the reciprocal translocations was markedly related to the dominant lethality

Reactivation of Immunological Response in Lethally X-Irradiated Mice Treated with Isogeneic Bone Marrow

Energy Technology Data Exchange (ETDEWEB)

Stankovic, V.; Slijepcevic, M.; Hrsak, I. [Institute Ruder Boskovic, Zagreb, Yugoslavia (Croatia)

1968-08-15

Male and female C57BL/H and CBA/H mice aged 10-12 weeks were used as recipients and donors, respectively. All recipient mice were given a lethal whole-body X-irradiation dose (850 R for C57BL and 950 R for CBA mice) followed by iv injection of 10 x 106 isogeneic eosin-negative bone-marrow cells suspended in 0.5 ml of Hank's solution. The number of eosin-positive cells was less than 10%. The state of immunological responsiveness of irradiated recipients was measured at different time intervals up to 86 days after irradiation. The immune response to bacterial antigen was measured with the titre of agglutinating antibodies in serum six days after iv antigenic stimulation with a suspension of 2 x 10{sup 7} killed Salmonella typhimurium cells. The immune response to tissue antigens was evaluated by: (a) the effectiveness of the spleen cells from isologous radiation chimeric parental mice in preventing bone marrow from F{sub 1} (C57BL x CBA) hybrid donor from therapeutically affecting lethally irradiated F j recipient mice; (b) the effectiveness of the spleen cells in inducing splenom egaly in recipient F{sub 1} hybrid mice (Simonsen test). It was found that the responsiveness to bacterial antigens reappears much earlier and increases much faster than the immunological responsiveness to tissue antigens. (author)

Effects of sub-lethal dose of γ-irradiation on lysosomal enzymes in tissue of pigeon

International Nuclear Information System (INIS)

Shah, V.C.; Gadhia, P.K.

1979-01-01

Effects of total body γ-irradiation with sub-lethal dose (300 rad) on three lysosomal enzymes namely acid phosphatase, ribonuclease-II and deoxyribonuclease-II have been studied in pigeons. Liver, kidney and spleen were the tissues studied at different intervals like 1-h, 24-h, 48-h, and 72-h of irradiation. The specific activities ('crude' fraction) of acid phosphatase and ribonuclease-II increased significantly in spleen and liver at 48-h of irradiation. The activity of deoxyribonuclease-II in liver and spleen was increased only at 72-h post-irradiation. On the other hand, the total activities of three lysosomal enzymes did not show remarkable change throughout 72-h of irradiation. (author)

Low survival of mice following lethal gamma-irradiation after administration of inhibitors of prostaglandin synthesis

International Nuclear Information System (INIS)

Hofer, M.; Pospisil, M.; Tkadlecek, L.; Viklicka, S.; Pipalova, I.; Hola, J.

1992-01-01

An impairment was observed of the survival of mice subjected to whole-body gamma-irradiation with a lethal dose of 10 Gy and treated with a repeated postirradiation administration of the prostaglandin synthesis inhibitors (PGSIs) indomethacin or diclofenac. Morphological examination of the gastrointestinal tract and estimation of the blood loss into its lumen in animals treated with diclofenac did not show serious damage such as hemorrhages or perforation, but revealed structural injury to the intestinal mucosa indicating inflammatory processes. The lesions found are supposed to be connected with increased intestinal permeability which leads to endotoxin escape from the gut and a subsequent increased mortality rate of irradiated animals. It may be concluded that PGSIs are not suitable for the management of radiation sickness after an exposure to lethal doses of ionizing radiation. (author) 2 tabs., 4 figs., 20 refs

Influence of vaccination with Bordetella pertussis cells on haemopoiesis in sublethally irradiated mice and their radiation lethality

International Nuclear Information System (INIS)

Kwiek, S.; Bitny-Szlachto, S.

1978-01-01

Post-irradiation lethality of CFW mice has turned out to be enhanced by vaccination with Bordetella pertussis cells 10 min., 48 hrs. prior or 48 hrs. after the exposure to X-rays. The sensitization factor was found to be 1.23, as it revealed by decrease of radiation LD 50 . Granulopoiesis and erythropoiesis proved to be stimulated by vaccination, in mice irradiated with 200 or 400 R but not in those after 600 R. Direct radiosensitivity of CFU was not altered by vaccination, but the subsequent loss of bone marrow stem cells was enhanced in vaccinated mice. On the other hand, endocolonization of spleens with bone marrow stem cells has turned out to be highly enhanced by the vaccine, resulting in confluent growth of colonies. This effect of the vaccine was not abolished by hydroxyurea given 15 min. or 1 hr. after vaccination. Enhanced post-irradiation lethality is considered to result from fall of the bone marrow stem cell pool below the level indispensable to ensure the post-irradiation recovery of the haemopoietic system. (author)

Influence of radioprotectors on total body weight evolution and on oxygen consumption in lethal dose irradiated animals. (Preliminary study)

International Nuclear Information System (INIS)

Fatome, M.; Martine, G.; Bargy, E.; Andrieu, L.

Comparison of total body weight evolution and oxygen consumption in lethal dose irradiated animals, protected by various well known radioprotective substances, isolated or in mixture, with evolution and consumption of non protected animals irradiated at the same dose and with these of check animals [fr

Poly(ADP-ribose) metabolism in X-irradiated Chinese hamster cells: its relation to repair of potentially lethal damage

International Nuclear Information System (INIS)

Ben-Hur, E.; Elkind, M.M.

1984-01-01

Nicotinamide-adenine dinucleotide (NAD + ) is the substrate used by cells in poly(ADP-ribose) synthesis. X-irradiation of log-phase Chinese hamster cells caused a rapid decrease in NAD + levels which was linearly dependent on radiation dose. The activity of ADP-ribosyl transferase (ADPRT) also increased linearly with radiation dose. The decrease of NAD + was slower, and the increase in ADPRT activity was less pronounced, in a radiation sensitive line, V79-AL162/S-10. An inhibitor of ADPRT, m-aminobenzamide, largely prevented the depletion of cellular NAD + and reduced the rate at which ADPRT activity disappeared during post-irradiation incubation. Post-irradiation treatment with hypertonic buffer or with medium containing D 2 O-which inhibit repair of radiation-induced potentially lethal damage-enhanced the depletion of NAD + and prevented the reduction in ADPRT activity following irradiation. The characteristics of the effects of treatment with hypertonic buffer on NAD + metabolism were qualitatively similar to the effects that such treatment has on radiation-induced cell killing. These results suggest that poly(ADP-ribose) synthesis after irradiation plays a role in the repair of potentially lethal damage. (author)

Some biochemical characteristics of a toxic substance isolated from organs of lethally irradiated animals in the course of the intestinal syndrome

Energy Technology Data Exchange (ETDEWEB)

Meter, J D; Sirota, N S [Tsentral' nyj Nauchno-Issledovatel' skij Rentgeno-Radiologicheskij Inst., Leningrad (USSR)

1976-05-01

A toxic substance isolated from organs of lethally irradiated (1300 rads) animals in the period when intestinal syndrome has developed is classified according to the parameters under study (namely, the molecular weight, UV-absorption curve, extinction coefficient, specific monosaccharides, the presence and percentage of KDA, etc.) as lipopolysaccharide of Escherichia coli, the main inhabitant of the gastroenteric tract of mice. That endotoxins (sensitivity to which is increased in this period of radiation sickness) are detected in the blood and organs of lethally irradiated animals, might indicate their participation in the pathogenesis of the intestinal syndrome.

Some biochemical characteristics of a toxic substance isolated from organs of lethally irradiated animals in the course of the intestinal syndrome

International Nuclear Information System (INIS)

Meter, J.D.; Sirota, N.S.

1976-01-01

A toxic substance isolated from organs of lethally irradiated (1300 rads) animals in the period when intestinal syndrome has developed is classified according to the parameters under study (namely, the molecular weight, UV-absorption curve, extinction coefficient, specific monosaccharides, the presence and percentage of KDA, etc.) as lipopolysaccharide of Escherichia coli, the main inhabitant of the gastroenteric tract of mice. That endotoxins (sensitivity to which is increased in this period of radiation sickness) are detected in the blood and organs of lethally irradiated animals, might indicate their participation in the pathogenesis of the intestinal syndrome

Lethal mutation of internal irradiation brown planthopper (Nilaparvita lugens Stal)

International Nuclear Information System (INIS)

Wahid, R.A.

1988-01-01

The moulting IVth of BPH nympha were irradiated internally with radiophosphorous 32-P 1 uCi/ml, 10 uCi/ml, 50 uCi/ml, 100 uCi/ml, and 500 uCi/ml concentrations respectivelly. An observation was carried out to determines heredity of hopper sterilities from the mating groups of R male x N female, R male x R female, and N male x R female. The 32-P concentration below of 50 uCi/ml seemed to be the substerile dose, however, the dominant lethal mutation has been visually shown by R male x R female F1 mating group. The hereditary lines of F1, F2, F3, and F4 of the hopper sterilities wich were indicated by the nympha hatch ability have some significant correlations (r1= -0.77, r2= -0.92, r3= -0.93 and r4= -0.85). Thus, the resesif lethal mutations visually showed by F3 and F4 from all of the 100 uCi/ml and 50 uCi/ml treated groups. (author). 10 refs, 2 figs, 2 tabs

Sensitivity of Vibrio cholerae cells to lethal and mutagenic effect of UV-irradiation mediated by plasmids

International Nuclear Information System (INIS)

Tiganova, I.G.; Evdokimova, N.M.; Aleshkin, G.I.

1988-01-01

The effect of UV-irradiation on Vibrio cholerae cells and its changes mediated by the plasmid R245 have been studied. Vibrio cholerae strains 569B and RV31 have been shown to be considerably more sensitive to lethal effect of UV-irradiation as compared with Escherichia coli and Salmonella typhimurium cells. Highly toxigenic strain 569B and practically atoxigenic strain RV31 have the same UV-sensitivity. Lethla effect of UV-irradiation on Vibrio cholerae cells is incresed when the irradiated cells are plated on enriched media. UV-induction of mutations was not registered in plasmidless strains of Vibrio cholerae. Plasmid R245 increase UV-resistance of vibrio cells and makes them UV-mutable

Regulation of immune responses in SJL and F1 hybrid mice by gamma-irradiated syngeneic lymphoma cells

International Nuclear Information System (INIS)

Katz, I.R.; Nagase, F.; Bell, M.K.; Ponzio, N.M.; Thorbecke, G.J.

1984-01-01

Syngeneic mixed lymphocyte-stimulating la+ lymphomas of SJL mice [reticulum cell sarcoma(s) (RCS)] were found to modulate immune responses in vivo. Simultaneous injection of 2 X 10(7) gamma-irradiated or glutaraldehyde-fixed RCS cells with the antigen sheep red blood cells (SRBC) or 2,4,6-trinitrophenol (TNP)-Ficoll markedly suppressed the subsequent plaque-forming cell response in the spleen. The suppression of the anti-SRBC response was prevented by pretreatment of the mice with cyclophosphamide, whereas the suppression of the anti-TNP-Ficoll response was not affected. RCS injection induced high interferon serum titers within 24 hours after injection, which were not prevented by pretreatment with cyclophosphamide. Injection of gamma-irradiated RCS cells (gamma-RCS) or RCS cell extract 2 days prior to antigen enhanced the anti-SRBC but markedly suppressed the anti- TNP-Ficoll response. Injection of RCS both on day -2 and day 0 enhanced the anti-SRBC response. SJL mice 8-9 months of age showed much less or no suppression when gamma-RCS cells were injected on day 0. Certain F1 hybrids of SJL also showed the gamma-RCS-induced suppression of the anti-SRBC response. Suppression was seen in SJL X BALB.B but not in SJL X BALB/c mice and in SJL X A.TH but not in SJL X A.TL mice, suggesting an I-region effect. F1 hybrids of SJL by B10 background mice showed no significant suppression. Enhancement of the anti-SRBC response by prior injection of gamma-RCS was seen in all F1 hybrid mice examined

Models for pulmonary lethality and morbidity after irradiation from internal and external sources

International Nuclear Information System (INIS)

Scott, B.R.; Filipy, R.E.; Hahn, E.F.

1989-05-01

This report provides a hazard-function model for estimating the risk of death from radiation pneumonitis and/or pulmonary fibrosis following a light-water nuclear power accident. A similar model is also provided for estimating the prevalence of respiratory functional morbidity among those that survive death from acute effects. Hazard-function models for lethality and for morbidity were constructed using the cumulative hazard estimator H, which is related to the risk estimator R through the equation R = 1-exp(-H). The estimator H can be calculated using information provided in the report. The method of calculation depends on the exposure scenario. In general, the total normalized dose X for lethality or for morbidity is calculated. For lethality, X = 1 corresponds to a median lethal dose (LD 50 ); for morbidity, X = 1 corresponds to a median effective dose (ED 50 ). H is related to X by the equation H = 1n(2)X/sup V/, where V depends on the type of radiation (or radiations) involved. Contributions to X can arise from each of two main modes of exposure: (1) brief exposure of the lung, at a relatively high dose rate, to mainly external gammas, followed by (2) chronic internal alpha, and/or beta, and/or gamma irradiation of the lung. Equations are provided for calculating the contributions to X from both modes of exposure. 73 refs., 16 figs., 2 tabs

Megakaryocytopoiesis and the number of thrombocytes after bone marrow cell transplantation in lethally irradiated mice

International Nuclear Information System (INIS)

Viktora, L.; Hermanova, E.; Zoubkova, M.

1977-01-01

Changes were studied in the number of thrombocytes in the peripheral blood and megakaryocytes in the bone marrow and spleen in lethally irradiated mice after the transplantation of bone marrow cells. It was found that the thrombocytes increased in dependence on time after transplantation with the maximal values around the 20th day. An increased megakaryocytopoiesis was observed not only in the bone marrow but also in the spleen. These ascertainments suggest the importance of the transplantation of bone marrow cells and the role of thrombocytes for the survival of the organism after irradiation. (author)

Sub-lethal irradiation of human colorectal tumor cells imparts enhanced and sustained susceptibility to multiple death receptor signaling pathways.

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Victoria Ifeadi

Full Text Available BACKGROUND: Death receptors (DR of the TNF family function as anti-tumor immune effector molecules. Tumor cells, however, often exhibit DR-signaling resistance. Previous studies indicate that radiation can modify gene expression within tumor cells and increase tumor cell sensitivity to immune attack. The aim of this study is to investigate the synergistic effect of sub-lethal doses of ionizing radiation in sensitizing colorectal carcinoma cells to death receptor-mediated apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: The ability of radiation to modulate the expression of multiple death receptors (Fas/CD95, TRAILR1/DR4, TRAILR2/DR5, TNF-R1 and LTβR was examined in colorectal tumor cells. The functional significance of sub-lethal doses of radiation in enhancing tumor cell susceptibility to DR-induced apoptosis was determined by in vitro functional sensitivity assays. The longevity of these changes and the underlying molecular mechanism of irradiation in sensitizing diverse colorectal carcinoma cells to death receptor-mediated apoptosis were also examined. We found that radiation increased surface expression of Fas, DR4 and DR5 but not LTβR or TNF-R1 in these cells. Increased expression of DRs was observed 2 days post-irradiation and remained elevated 7-days post irradiation. Sub-lethal tumor cell irradiation alone exhibited minimal cell death, but effectively sensitized three of three colorectal carcinoma cells to both TRAIL and Fas-induced apoptosis, but not LTβR-induced death. Furthermore, radiation-enhanced Fas and TRAIL-induced cell death lasted as long as 5-days post-irradiation. Specific analysis of intracellular sensitizers to apoptosis indicated that while radiation did reduce Bcl-X(L and c-FLIP protein expression, this reduction did not correlate with the radiation-enhanced sensitivity to Fas and/or TRAIL mediated apoptosis among the three cell types. CONCLUSIONS/SIGNIFICANCE: Irradiation of tumor cells can overcome Fas and TRAIL

Homogeneous antibodies in lethally irradiated and autologous bone marrow reconstituted Rhesus monkeys

International Nuclear Information System (INIS)

Berg, P. Van Den; Radl, J.; Loewenberg, B.; Swart, A.C.W.

1976-01-01

Ten Rhesus monkeys were lethally irradiated and reconstituted with autologous bone marrow. During the restoration period, the animals were immunized with DNP-Rhesus albumin and IgA1lambda-10S human paraprotein. One or more transient homogenous immunoglobulin components appeared in sera of all experimental monkeys. In four animals, these homogeneous immunoglobulins were shown to be specific antibodies against DNP-Rhesus albumin. They gradually became as heterogeneous as those in control monkeys which were immunized but not irradiated and transplanted. The onset of the specific antibody response after immunization was slightly delayed in the experimental group. On determining the time necessary to reach normalization of the overall immunoglobulin levels and the normal heterogeneity of the immunoglobulin spectrum, it was found to be more than 1 year in most of the animals. (author)

A single dose of an inhibitor of cyclooxygenase 2, meloxicam, administered shortly after irradiation increases survival of lethally irradiated mice

Czech Academy of Sciences Publication Activity Database

Hofer, Michal; Pospíšil, Milan; Dušek, L.; Hoferová, Zuzana; Weiterová, Lenka

2011-01-01

Roč. 176, č. 2 (2011), s. 269-272 ISSN 0033-7587 R&D Projects: GA ČR(CZ) GA305/08/0158 Grant - others:GA ČR(CZ) GAP303/11/0128 Program:GA Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : cyclooxygenase-2 inhibition * lethal irradiation * survival Subject RIV: BO - Biophysics Impact factor: 2.684, year: 2011

Tanacetum parthenium leaf extract mediated survival protection in lethally irradiated Swiss albino mice

International Nuclear Information System (INIS)

Shetty, Prashanth; Pooja, S.; Suchetha Kumari, N.; Shetty, Jayaram; Peter, Alex John; Jose, Jerish M.

2016-01-01

Search for less-toxic radioprotectors has spurred interest in the development of natural products. In Ayurveda, the traditional medicine, Tanacetum species have been used to treat ailments since ancient times throughout the world. Effects of the administration of different concentrations of Tanacetum parthenium leaf aqueous extract (TPLA), Tanacetum parthenium leaf ethanolic extract (TPLE) were investigated in Swiss albino mice. Mice (20-25 g) were randomly divided into 8 groups of ten animals each. The control group and the radiation group were treated daily with oral administration of saline for 15 days. Each subgroups of TPLA and TPLE were treated with doses of 50, 100 and 250 mg/kg daily for 15 days. On the 15th day, all were irradiated with 10 Gy whole body irradiation. Survival was observed daily up to 30th post-irradiation day. Data were analysed using the Kaplan-Meier survival curves. The significance difference in survival between control, radiation and treatment groups were observed (P < 0.001). Current studies revealed the protective effect of Tanacetum parthenium rendering high survivability in lethally irradiated mice. (author)

Cell-mediated immune response to syngeneic uv induced tumors. I. The presence of tumor associated macrophages and their possible role in the in vitro generation of cytotoxic lymphocytes

International Nuclear Information System (INIS)

Woodward, J.G.; Daynes, R.A.

1978-01-01

A primary in vitro sensitization system employing a chromium release assay was utilized to investigate reactivity of murine spleen cells toward syngeneic ultraviolet (uv) light induced fibrosarcomas. These tumors are immunologically rejected in vivo when implanted into normal syngeneic mice but grow progressively when implanted into syngeneic mice that had previously been irradiated with subcarcinogenic levels of uv light. Following appropriate sensitization, spleen cells from both normal and uv irradiated mice are capable of developing cytotoxic lymphocytes in vitro against the uv induced tumors. It was subsequently discovered that in situ uv induced tumors all contained macrophages of host origin that became demonstrable only after enzymatic dissociation of the tumor tissue. These macrophages were immunologically active in vitro as their presence in the stimulator cell population was necessary to achieve an optimum anti-tumor cytotoxic response following in vitro sensitization. Anti-tumor reactivity generated by mixing spleen cells and tumor cells in the absence of tumor derived macrophages could be greatly enhanced by the addition of normal syngeneic peritoneal macrophages. When in vitro anti-tumor reactivity of spleen cells from normal and uv treated mice was compared under these conditions we again found no significant difference in the magnitude of the responses. In addition, the cytotoxic cells generated in response to uv induced tumors appeared to be highly cross reactive with respect to their killing potential

Antibody-mediated suppression of grafted lymphoma. III. Evaluation of the role of thymic function, non-thymus-derived lymphocytes, macrophages, platelets, and polymorphonuclear leukocytes in syngeneic and allogeneic hosts

International Nuclear Information System (INIS)

Shin, H.S.; Hayden, M.; Langley, S.; Kaliss, N.; Smith, M.R.

1975-01-01

Syngeneic or allogeneic mice pretreated with sublethal whole-body irradiation were rendered incapable of suppressing the growth of grafted tumor cells sensitized with alloantibody. The growth of sensitized tumor cells was suppressed when they were mixed with donor effector cells from mice syngeneic or allogeneic to the recipients and then were inoculated in irradiated recipients. Three donor-host combinations were used to study the suppression of the murine lymphoma 6C3HED indigenous to C3H mice. These were C3H donor cells in C3H recipients, C57BL/6 donor cells in C3H recipients, or C57BL/6 donor cells in C57BL/6 recipients. In all three combinations, macrophages obtained from an inflammatory exudate, exudate lymphocytes not bearing theta antigen, and platelets were, in descending order of effectiveness, consistently active in restoring antibody-mediated suppression of tumor growth in irradiated hosts. Prior irradiation of the transferred lymphocytes somewhat diminished their effectiveness. Freeze-thawed or heat-killed macrophages (but not freeze-thawed platelets or lymphocytes) were effective in restoration. Peripheral blood mononuclear leukocytes and splenic lymphoid cells were not active in the recipients syngeneic to the donor cells but were active in recipients allogeneic to the donor cells. Polymorphonuclear leukocytes isolated from peripheral blood or an inflammatory exudate were not active. Intact thymic function seems unimportant since antibody-mediated suppression took place as effectively in thymectomized mice as in normal controls. (U.S.)

Induction of lethal mutations in the x-chromosome of unirradiated Drosophila oocytes after fertilization by irradiated spermatozoa

International Nuclear Information System (INIS)

Shaposhnikov, M.V.; Zainullin, V.G.

2003-01-01

Full text: In primary study on Drosophila it was found that irradiated male X-chromosomes induce recessive lethals in unirradiated female homologues (Abeleva et al., 1961, Radiobiologya. 1:123-126). The same effects were obtained in Drosophila in some recent investigations. The mechanisms of these effects is unknown. However it may be responsible for low-dose radiation effects as it induce mutations in unirradiated DNA. We assume that this effect may be a result of activation of error prone repair in response to preliminary DNA lesions in irradiated chromosome. In this research we analyse the frequencies of the recessive lethal mutations in the X-chromosome of Drosophila females mated with irradiated Basc males. We used acute irradiation with a dose rate of 10 Gy. For testing our hypothesis we use the mus209 and mei-41 mutant females. Mus209 is a PCNA gene homologue and mei-41 is a homologue of ATM gene. These genes are involved in post-replication DNA repair which may be error prone repair in Drosophila. It was obtained the tendency to decreasing the mutation rate at the mei-41[D5] background and decreasing mutation rate in mus209[B1] background in comparison with wild type strains CS (p<0.05). The obtained results demonstrate the possible role of mus209[B1] and mei-41[D5] genes in the inducing of mutations in the unirradiated X-chromosome in the presence of irradiated homologue

Influence on DNA repair inhibitors on dominant lethal factors after gamma irradiation

International Nuclear Information System (INIS)

Engl, D.

1978-01-01

Experiments were performed in order to test the hypothesis of a correlation between ionizing radiation and DNA repair inhibition under in vivo conditions. In a biometrically planned dominant lethal test on mice, the repair inhibition on the male gametes by butazolidine, TWEEN 80 and vitamin A was studied after gamma irradiation at 20 rad/10 min. No effect was observed in the case of butazolidine and TWEEN 80, whereas the influence of a high concentration of vitamin A (1 million IE/kg) was just at the statistical significancy threshold. (G.G.)

Participation of lymphocytes in hemopoiesis regeneration under local irradiation of the body

International Nuclear Information System (INIS)

Gol'dberg, E.D.; Dygaj, A.M.

1982-01-01

Lymphocyte participation in regulation of a pool of stem blood-producing cells using a model of local irradiation of bone marrow was studied. Right pelvic limb of BALB/c strain mice was exposed to local X-radiation at a dose of 7.0 Gy. During different periods after the irradiation the animals were killed and the total number of nucleus-containing cells in thymus, spleen, bone marrow from irradiated and screened femurs were counted. Smears of bone marrow were used to calculate myelogram. To study thymocyte effect on postradiation regeneration of hemopoesis, each of thymectomized mice were injected intravenously 4x10 7 viable thymocytes. Processes of the postradiation regeneration of hemopoesis were specially investigated in animals against the background of intraperitoneal injection of antithymocytic heterologous serum. The population of stem blood-producing cells of bone marrow was studied by the method of exogenic cloning in the body of syngenic recipient lethally irradiated (7.5 Gy). It is shown that during the period before active recovery of hemopoesis observed is the selective accumulation of lymphocytes of predominantly thymus origin only in irradiated blood-producing tissue. T lymphocytes stimulated colony-forming activity of bone marrow and accelerated the postradiation regeneration of hemopoesis

Transplantation of cryopreserved allogeneic bone marrow after its long-term storage to lethally irradiated dogs

International Nuclear Information System (INIS)

Novikova, N.N.; Fedotenkov, A.G.; Sukyasyan, G.V.; Timakova, L.A.

1982-01-01

The study of the dog bone marrow preserved at -196 deg C during 6-12 years has shown that in the body of lethally irradiated animals (8Gy), due to the antigenic difference in the tissues of the donor and the irradiated recipients, the cells of cryopreserved allogeneic bone marrow were differentiated by the lymphoid type similar to that observed in transplantation of freshly prepared myelocaryocytes. However, their proliferative activity in the period of active lymphocyte transformation was quantitatively less manifest than in freshly transplanted cells. The results of the study evidence that the bone marrow cells cryopreserved during 6-12 years retain their functional activity

Repair of potentially lethal and sublethal radiation damage in x-irradiated ascites tumor cells

International Nuclear Information System (INIS)

Tsuboi, Atsushi; Okamoto, Mieko; Tsuchiya, Takehiko.

1985-01-01

The ability of cells to repair cellular radiation damage during the growth of TMT-3 ascites tumor and the effect of host reaction on the repair ability were examined by using an in vitro assay of cell clonogenicity after in situ irradiation of tumor cells. In single-dose experiments, the repair of potentially lethal radiation damage (PLD) was observed in stationary phase cells (12-day tumor) of the unirradiated host, but not in exponential phase cells (3-day tumor) of the unirradiated host animals. However, if previously irradiated host animals were used, even the exponentially growing tumor cells showed repair of PLD. In two-dose experiments, the ability to repair sublethal radiation damage (SLD) in exponential phase tumor cells was less than that of stationary phase cells in the unirradiated host. In the pre-irradiated host, the extent of the repair in exponential phase cells was somewhat enhanced. These results suggest that irradiation of host animals might suppress a factor that inhibits repair, resulting in enhancement of the repair capability of tumor cells. (author)

Changes in activities of adaptive liver enzymes in rats after non-lethal x-irradiation

International Nuclear Information System (INIS)

Toropila, M.; Ahlersova, E.; Ahlers, I.; Benova, K.

1998-01-01

The effect of a single dose of whole-body X-irradiation of 2.39 Gy (250 R) on the activities of selected adaptive rat liver enzymes and blood serum corticosterone concentrations was followed for a period of 28 days. Rats of Wistar strain SPF breeding (VELAZ Prague) were used. Both irradiated and control animals were fed in pairs with the same amount of feed as was consumed by irradiated animals in the pilot experiment. The feed intake of irradiated animals decreased significantly until the fourth day. During the rest of the experimental period no significant differences were recorded in feed intake between the experimental and control groups. The activity of tyrosine aminotransferase (TAT) in the liver of irradiated animals increased, with the exception of the initial period. Similar changes were recorded in the activity of tryptophane-2-3 dioxygenase (TO). A significant increase on the third day and a significant decrease from the seventh day after irradiation was recorded in the activity of aspartate aminotransferase (AST). Similar changes were observed with alanine aminotransferase (ALT). It is necessary to stress that the activity of this enzyme decreased also on the first day after irradiation. Until the third day there was a marked increase of serum corticosterone in the irradiated animals. The results point not only towards significant changes to the parameters observed, caused by a non-lethal irradiation dose, but also towards the importance of the nutritional regime, so-called paired feeding

Cell lethality after selective irradiation of the DNA replication fork

International Nuclear Information System (INIS)

Hofer, K.G.; Warters, R.L.

1985-01-01

It has been suggested that nascent DNA located at the DNA replication fork may exhibit enhanced sensitivity to radiation damage. To evaluate this hypothesis, Chinese hamster ovary cells (CHO) were labeled with 125 I-iododeoxyuridine ( 125 IUdR) either in the presence or absence of aphidicolin. Aphidicolin (5 μg/ml) reduced cellular 125 IUdR incorporation to 3-5% of the control value. The residual 125 I incorporation appeared to be restricted to low molecular weight (sub-replicon sized) fragments of DNA which were more sensitive to micrococcal nuclease attack and less sensitive to high salt DNase I digestion than randomly labeled DNA. These findings suggest that DNA replicated in the presence of aphidicolin remains localized at the replication fork adjacent to the nuclear matrix. Based on these observations an attempt was made to compare the lethal consequences of 125 I decays at the replication fork to that of 125 I decays randomly distributed over the entire genome. Regardless of the distribution of decay events, all treatment groups exhibited identical dose-response curves (D 0 : 101 125 I decays/cell). Since differential irradiation of the replication complex did not result in enhanced cell lethality, it can be concluded that neither the nascent DNA nor the protein components (replicative enzymes, nuclear protein matrix) associated with the DNA replication site constitute key radiosensitive targets within the cellular genome. (orig.)

Diabetes susceptibility of BALB/cBOM mice treated with streptozotocin. Inhibition by lethal irradiation and restoration by splenic lymphocytes

International Nuclear Information System (INIS)

Paik, S.G.; Blue, M.L.; Fleischer, N.; Shin, S.

1982-01-01

In genetically susceptible strains of mice, repeated injections of a subdiabetogenic dose of streptozotocin induces the development of progressive insulin-dependent hyperglycemia. We showed previously that host T-cell functions play an obligatory etiologic role in this experimental disease by demonstrating that the athymic nude mouse is resistant to diabetes induction unless its T-cell functions are reconstituted by thymus graft. Here we show that lethal irradiation of euthymic (+/nu) mice of BALB/cBOM background causes selective resistance of the mice to the diabetogenic effects of the multiple low doses of streptozotocin without affecting their sensitivity to a high pharmacologic dose of the toxin. We also show that reconstitution of the irradiated mice with splenic lymphocytes causes the restoration of diabetes susceptibility. Lethally irradiated mice thus represent a useful experimental model for analyzing the host functions involved in the development of this disease. These results provide an additional support for the hypothesis that the induction of diabetes in this model system is mediated by an autoimmune amplification mechanism

MASM, a Matrine Derivative, Offers Radioprotection by Modulating Lethal Total-Body Irradiation-Induced Multiple Signaling Pathways in Wistar Rats

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Jianzhong Li

2016-05-01

Full Text Available Matrine is an alkaloid extracted from Sophora flavescens Ait and has many biological activities, such as anti-inflammatory, antitumor, anti-fibrosis, and immunosuppressive properties. In our previous studies, the matrine derivative MASM was synthesized and exhibited potent inhibitory activity against liver fibrosis. In this study, we mainly investigated its protection against lethal total-body irradiation (TBI in rats. Administration of MASM reduced the radiation sickness characteristics and increased the 30-day survival of rats before or after lethal TBI. Ultrastructural observation illustrated that pretreatment of rats with MASM significantly attenuated the TBI-induced morphological changes in the different organs of irradiated rats. Gene expression profiles revealed that pretreatment with MASM had a dramatic effect on gene expression changes caused by TBI. Pretreatment with MASM prevented differential expression of 53% (765 genes of 1445 differentially expressed genes induced by TBI. Pathway enrichment analysis indicated that these genes were mainly involved in a total of 21 pathways, such as metabolic pathways, pathways in cancer, and mitogen-activated protein kinase (MAPK pathways. Our data indicated that pretreatment of rats with MASM modulated these pathways induced by TBI, suggesting that the pretreatment with MASM might provide the protective effects on lethal TBI mainly or partially through the modulation of these pathways, such as multiple MAPK pathways. Therefore, MASM has the potential to be used as an effective therapeutic or radioprotective agent to minimize irradiation damages and in combination with radiotherapy to improve the efficacy of cancer therapy.

Survival of bone marrow-engrafted mice subsequent to protection from lethal radiation by WR 2721

International Nuclear Information System (INIS)

Kinnamon, K.E.; Ketterling, L.L.; Ledney, G.D.; Lorenz, G.B.; Mioduszewski, R.J.; Stampfli, H.F.

1980-01-01

For the first time data are presented for animals treated with bone marrow cells after lethal radiation exposure while protected with WR 2721 (the single radioprotective chemical compound with the highest known dose reduction factor). The LD 50 30 (lethal dose to 50% in 30 days) for mice exposed to whole-body 60 Co radiation was elevated from 824 +- 8 rad in unprotected and untreated mice to (a) 1181 +- 33 rad in animals which received syngeneic bone marrow cells after exposure; (b) 1342 +- 27 rad in animals which received WR 2721 before radiation exposure; and (c) 1608 +- 33 rad in animals receiving both the radioprotective agent before exposure and bone marrow engraftment after exposure

Dominant lethal mutations in insects with holokinetic chromosomes: irradiation of pink bollworm sperm

International Nuclear Information System (INIS)

Berg, G.J.; LaChance, L.E.

1976-01-01

Adult males of the pink bollworm, Pectinophora gosypiella (Saunders), were irradiated with 19 and 30 krad of gamma radiation and mated with virgin, untreated females. Males treated with 19 or 30 krad of gamma radiation, at 2 to 24-h or 48 to 72-h postemergence, respectively, did not show reduced mating frequency compared with the untreated male controls. However, transfer of eupyrene sperm was reduced by treating 2 to 24-h postemergent males with 30 krad. Irradiation with 19 or 30 krad did not cause complete male sterility; 12.7 and 16.8 percent, respectively, of the fertilized eggs hatched. Eggs fertilized with irradiated sperm were examined cytologically and showed a retardation of embryonic development up to the blastoderm stage. From the blastoderm stage onward, development was parallel to those eggs which were fertilized by unirradiated sperm. Of the embryos in the groups treated with 30 and 19 krad, 51.3 to 66.6 percent, respectively, developed into fully differentiated, normal-appearing, prehatch embryos. The radiation-induced dominant lethal mutations were, generally, expressed very late in embryonic development

Fixation of potentially lethal radiation damage by post-irradiation exposure of Chinese hamster cells to 0.5 M or 1.5 M NaCl solutions

International Nuclear Information System (INIS)

Raaphorst, G.P.; Dewey, W.C.

1979-01-01

The effect of 0.05 M and 1.5 M NaCl treatments on CHO cells during and after irradiation has been examined. Treatment with either hypotonic or hypertonic salt solutions during and after irradiation resulted in the fixation of radiation damage which would otherwise not be expressed. The half time for fixation was 4 to 5 min, and the increased expression of the potentially lethal damage by anisotonic solutions was mainly characterized by large decreases in the shoulder of the survival curve, as well as by decreases in Dsub(o). Fixation of radiation damage at 37 0 C occurred to a much greater extent for the hypertonic treatment than for the hypotonic treatment and was greater at 37 0 C than at 20 0 C. Although both the hypotonic and hypertonic treatments during and after irradiation reduced or eliminated the repair of sublethal and potentially lethal damage, treatment during irradiation only, radiosensitized the cells when the treatment was hypotonic, and radioprotected the cells when the treatment was hypertonic. These observations are discussed in relation to salt treatments and different temperatures altering competition between repair and fixation of potentially lethal lesions, the number of which depends on the particular salt treatment at the time of irradiation. (author)

Inhibition of tumor growth in syngenetic chimeric mice mediated by a depletion of suppressor T cells

International Nuclear Information System (INIS)

Rotter, V.; Trainin, N.

1975-01-01

Syngeneic chimeric (lethally irradiated and reconstituted with syngeneic bone marrow cells) mice manifested an increased resistance to the development of Lewis lung carcinoma. In addition, these mice had a higher response to polyvinylpyrrolidone and a reduced reactivity to T mitogens. The present findings suggest that syngeneic chimeric mice lack suppressor T cells shown to regulate the development of Lewis lung tumor and the response to polyvinylpyrrolidone. Other components of the T cell population, such as helper cells responding to sheep red blood cells or cells involved in allograft rejection, assayed in these syngeneic chimeras were found unaffected. The fact that chimeric mice are deficient in a certain suppressor T cell population whereas other T activities are normal suggests the existence of different cell lines within the T cell population. (U.S.)

Combination use of lentinan with x-ray therapy in mouse experimental tumor system, (2). Combination effect on MM102 syngeneic tumor

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Shiio, Tsuyoshi; Ohishi, Kazuo; Tsuchiya, Yoshiharu; Niitsu, Iwayasu; Hayashibara, Hiromi; Yoshihama, Takashi; Moriyuki, Hirobumi

1988-03-01

C3H/He mice transplanted syngeneic MM102 tumor subcutaneously in the footpad were used to study the timing of administration of lentinan when combined with local irradiation of X-ray. In combination with 1,000 rads irradiation, the administration of lentinan after X-ray was not effective. When lentinan was administered in combination with 2,000 to 3,000 rads irradiation, the growth of tumor was decreased significantly in comparison with the groups which received radiotherapy alone and those that received lentinan alone. The administration of lentinan before irradiation was effective at the same degree in the group that received lentinan after irradiation. Life prolongation effect was also observed in the group that received lentinan before and after irradiation, and 4 mice among 8 tested mice were survived at 70th day after tumor transplantation.

Protective properties of plasma of burnt and irradiated rats against lethal effect of endotoxins in vivo

Energy Technology Data Exchange (ETDEWEB)

Budagov, R S; Chureyeva, L N

1984-10-01

The purpose of this work was to estimate protective properties of plasma in disease with increased endotoxemia. Burns and acute radiation sickness were used as models of suppression of physiological mechanisms of detoxication. Experiments were performed on male Wistar rats and mice, which received 3rd degree burns over 15% of the body surface, whole body gamma irradiation at 7.5 Gr or both. At 3 hours, 3, 7 and 12 days after the exposure the animals were decapitated and blood collected. The irradiated mice received 0.2 ml endotoxin intraperitoneally, 1.0 ml freshly prepared rat plasma, then the lethality of the mice in 24 hours was observed. It was found that the plasma of intact rats was capable of decreasing the lethal effects of S. typhimurium and E. coli endotoxins in vivo in mice. Deep skin burns, acute radiation sickness and the combined effects of radiation and thermal injury did not change this phenomenon. The plasma of the experimental rats retained the protective properties at various periods of time after the thermal, radiation and combined exposures. The functioning of the humoral detoxication mechanism is radioresistant, indirectly indicating the nonimmunoglobulin nature of endotoxin inactivators. 19 references.

Effect of allogenic thymic cells on radioleukaemogenesis in AKR-T1ALD mice

International Nuclear Information System (INIS)

Legrand, E.; Sankar-Mistry, P.; Kressmann, M.C.

1975-01-01

When AKR mice are irradiated with a sub-lethal dose (4 times 175 R), thymic lymphosarcomas (L.S.) occur earlier than in controls. This accelerated leukaemogenesis is not inhibited by syngenic restoration with bone marrows cells (BM). Using the AKR/T1ALD substrain which bears 38 chromosomes with 1 metacentric markers, it has been shown that AKR radio-chimaeras restored by T1ALD BM developed two kinds of L.S.: early (radiation-induced) L.S. originating mainly from host cells surviving irradiation and late L.S. from donor cells. The experiments were to investigate the potential influence of normal allogenic thymic cells, with or without syngenic B.M., on the incidence, latency and origin of LS appearing in irradiated AKR recipients. Adding C3H allogenic thymic cells to syngenic B.M. increases the percentage of early L.S. whose latencies are unchanged. Besides, when C3H thymic cells are injected to irradiated controls without syngenic B.M. cells, L.S. are seen to occur significantly earlier than in just the irradiated animals alone. In radio-chimaeras restored by allogenic thymic cells and syngenic B.M., except in one case, all the L.S. were seen to originate from B.M. cells. The interpretation of these results depends on the possible role of allogenic thymic cells on host cells surviving the irradiation, or the exogeneous B.M. In the first case, allogenic thymocytes could induce a graft versus host reaction increasing the post-irradiation depletion of lymphoid system and hastening thymic endoregeneration which is supposed to be the first step towards leukaemogenesis. The second hypothesis, which seems the most likely, would be that C1H thymic cells could selectively act on host cells surviving irradiation and enhance the differenciation of haemopoietic precursors at the expense of the lymphoid cells [fr

Effect of restricted access to food on metabolic changes in lethally X-irradiated rats. I

International Nuclear Information System (INIS)

Toropila, M.; Ahlers, I.; Ahlersova, E.; Praslicka, M.

1982-01-01

Differences in the reaction of glucose in blood and in that of glycogen in liver in animals with free access to food and in those with restricted food intake to lethal irradiation by X-rays were studied. SPF bred male rats of the Wistar strain were fed by common laboratory diet and by tap water ad libitum (AL group) or food was accessible to them (in unlimited amounts) only in the period between 09.00 a. m. and 11.00 a. m. (meal-fed group, MF), all under standard laboratory conditions. After more than three weeks of adaptation to the nutrition patterns and 22 h after the last food intake, animals of both groups were irradiated with a single whole-body 14.35 Gy dose of X-rays and/or sham irradiated, respectively. Glucose concentration in blood was increased in both groups during the experiment; terminal hyperglycaemia was more expressed in the MF group. Due to the high initial glycogen concentration in the liver of MF irradiated animals the accumulation of glycogen was substantially lower and started later than in irradiated AL animals. (author)

Parental resistance of irradiated mice to (CBAXM523)F/sub 1/ lymphocytes: the destiny of transplanted cells, duration of resistance and its specificity

Energy Technology Data Exchange (ETDEWEB)

Kondrat' eva, T K; Fontalin, L N; Nagurskaya, E V; Novikova, T K; Blandova, Z K; Chernousov, A D [Akademiya Meditsinskikh Nauk SSSR, Moscow. Inst. Ehpidemiologii i Mikrobiologii

1979-05-01

The immunologic reactivity of mouse (CBAxM523)F/sub 1/ lymphocytes to alien antigens (ram erythrocytes) in the organisms of lethally irradiated CBA mice was studied. If the irradiation, cell transfer and antigen test-injection were performed on the same day, the activity of the transplant was suppressed as compared to the syngenic system. If the intervals between these procedures increased to three days the activity of donor cells was recovered. The retransplantation of recipient spleen cells to the irradiated CBA and F/sub 1/ mice demonstrated the viability of the transplanted cells and the absence of their transadaptation to nonsyngenic microenvironment. The resistance of the recipients could be overcome specifically by preliminary injection of F/sub 1/ mouse cells in combination with cyclophosphamide or without it. The results obtained suggest to conclude, that the genetic parental resistance of CBA mice to F/sub 1/ mouse cells is caused by the immunologically competent recipient cells that are inactivated after three days following irradiation. They do not produce a cytotoxic effect on donor cells, but limit temporarily the activity of the latter.

Regeneration of hemopoietic precursor cells in spleen organ cultures from irradiated mice: influence of genotype of cells injected and of the spleen microenvironment

International Nuclear Information System (INIS)

von Melchner, H.; Lieschke, G.J.

1981-01-01

The regeneration of hemopoietic precursor cells was monitored in spleen organ cultures from lethally irradiated mice injected with 10(7) normal syngeneic or allogeneic bone marrow cells. The important role of the microenvironment in supporting hemopoiesis was confirmed by the failure of mutant Sl/Sld spleens to support CFC regeneration in organ cultures. However, the extent and quality of the CFC regeneration was clearly dependent on the genetic properties of the injected cells. Evidence for this was obtained from the regeneration patterns of various CFC types in organ cultured spleens derived from different mouse donor-recipient strain combinations that maintained the differences in the bone marrow frequency of various CFC types characteristic of the donor strain

The effect of embryonal thymic calf extracts on neonatally thymectomized mice and on mice lethally irradiated with gamma rays

International Nuclear Information System (INIS)

Czaplicki, J.; Blonska, B.; Stec, L.

1981-01-01

The effect of embryonal thymic calf extracts (ETCE) on mice thymectomized at birth was investigated. ETCE was found to induce an increase in leukopenia and decrease in the level of serum gamma globulins; it also reduced survival time in mice. The effect of ETCE on lethally irradiated mice was also examined. Only long-term administration of ETCE prior to gamma irradiation at 750 rad prolonged the survival time of mice (40% permanent survival) as compared with irradiated controls; the leukocytes from mice retained mitotic capability. Neither long-term treatment with ETCE prior to irradiation at 1000 rad, nor short-term administration prior to 750 rad affected survival time. ETCE administered after irradiation of mice with 750 rad caused a rapid decrease in blood leukocytes and a significantly lowered survival time. (Auth.)

The effects of gut commensal bacteria depletion on mice exposed to acute lethal irradiation

International Nuclear Information System (INIS)

Hou Bing; Xu Zhiwei; Zhang Chenggang

2007-01-01

The prevention and management of bacterial infection are the mainstays of therapies for irradiation victims. However, worries about adverse effects arise from gut commensal flora depletion owing to the broad-spectrum antibiotics treatment. In the present study, we investigated the effects of gut bacteria depletion on the mice receiving total-body irradiation (TBI) at a single dose of 12 Gy. One group of mice was merely exposed to TBI but was free of antibiotic treatment throughout the experiment, while the other two groups of mice were additionally given broad-spectrum antibiotics, either from 2 weeks before or immediately after irradiation. The survival time of each animal in each group was recorded for analysis. Results showed that the mean survival time of mice was longest in the group without antibiotic treatment and shortest in the group treated with broad-spectrum antibiotics from 2 weeks before TBI. In conclusion, our data suggested that depletion of gut commensal bacteria with broad-spectrum antibiotics seemed deleterious for mammals receiving lethal TBI. (author)

Syngeneic graft-versus-host disease: a report of two cases and literature review.

Science.gov (United States)

Latif, T; Pohlman, B; Kalaycio, M; Sobecks, R; Hsi, E D; Andresen, S; Bolwell, B J

2003-09-01

Rappeport et al first reported the clinical syndrome of graft-versus-host disease (GVHD) in syngeneic bone marrow transplant patients. Recently, there have been more reports of a GVHD-like syndrome in syngeneic bone marrow transplant patients (SGVHD) that may result in significant clinical morbidity. A total of 17 cases of SGVHD in syngeneic bone marrow transplant patients have been reported to date in the medical literature. The current report reviews these cases and presents two additional cases of severe SGVHD that have occurred at our institution.

Lethal Effect of Gamma Irradiation on the Potato Tuber Moth, Phthorimaea operculella (Zeller) and its Effect on Certain Physicochemical Properties of Potato Tubers

International Nuclear Information System (INIS)

Aly, G.M.; Rizk, S. A.; Abdalla, R.S.; Sobeiha, A.M.K.; Dahroug, S.M.

2012-01-01

Exposure of 4-day-old eggs of Phthorimaea operculella (Zeller) to a dose level of 800 Gy of gamma radiation caused complete mortality and prevent egg hatching after 4 days from exposure to radiation. This dose level was considered as the lethal dose for the egg stage. The dose levels of 700 and 2800 Gy were considered lethal for the full grown larvae after periods of 9 and 1 days elapsed respectively from exposure to gamma radiation .The percent larval mortality increased with the increase of both the dose level applied and the time elapsed after exposure to gamma radiation. Irradiation of full grown pupae at the dose level 1900 Gy resulted in a complete reduction of adult emergence, reached 100 % . It could be concluded that gamma irradiation with a dose level 2800 Gy caused complete mortality to different stages of Phthorimaea operculella. Moreover, the physical and chemical properties of irradiated potato tubers did not significantly differ as compared to unirradiated tubers .This obtained, fatal irradiation dose did not exceed the safe limits recommended by the international organization FAO/WHO.

Clinical and symptomatological study of pigs subjected to a lethal dose of integral gamma irradiation; Etude clinique et symptomatologique chez le porc soumis a une irradiation gamma totale a dose letale

Energy Technology Data Exchange (ETDEWEB)

Vaiman, M; Guenet, J -L; Maas, J; Nizza, P

1966-05-01

Results are reported from a clinical and haematological study on a Corsican species of pigs wholly exposed to an approximately lethal dose of {gamma} radiation. The aim of this work was to examine the changes in the irradiation syndrome of irradiation for pigs to make it thus possible to devise further experiments, in particular in the therapeutic field. The dose received was 285 rads (measured as the absorption in the vertical antero-posterior medial plane). Data are presented on cyto-haematological changes in the blood circulating immediately after irradiation, and followed up to death, and changes in the medullary cytology after irradiation. The clinical picture of lethal radiation injury in swine is described. (authors) [French] Les auteurs rapportent les resultats d'une etude clinique et hematologique chez des porcs de race corse irradies in toto a dose sensiblement letale. Le but de cette etude etait de connaitre l'evolution du syndrome aigu d'irradiation chez le porc et de permettre ainsi le developpement d'experimentations ulterieures, en particulier dans le domaine therapeutique. La dose delivree etait de 285 rad (en dose absorbee au niveau du plan median vertical anteroposterieur. L'etude a porte essentiellement: 1. Sur les modifications cyclo-hematologiques du sang circulant immediatement apres l'irradiation, pour les differentes lignees cellulaires; l'evolution de ces modifications a ete notee jusqu'a la mort; 2. Sur les modifications de la cytologie medullaire apres irradiation (evolution du myelogramme et essai d'evaluation de la cellularite de la moelle osseuse);: 3. Sur les signes cliniques, d'ailleurs tres discrets, observes chez les porcs apres irradiation. (auteurs)

Clinical and symptomatological study of pigs subjected to a lethal dose of integral gamma irradiation; Etude clinique et symptomatologique chez le porc soumis a une irradiation gamma totale a dose letale

Energy Technology Data Exchange (ETDEWEB)

Vaiman, M.; Guenet, J.-L.; Maas, J.; Nizza, P

1966-05-01

Results are reported from a clinical and haematological study on a Corsican species of pigs wholly exposed to an approximately lethal dose of {gamma} radiation. The aim of this work was to examine the changes in the irradiation syndrome of irradiation for pigs to make it thus possible to devise further experiments, in particular in the therapeutic field. The dose received was 285 rads (measured as the absorption in the vertical antero-posterior medial plane). Data are presented on cyto-haematological changes in the blood circulating immediately after irradiation, and followed up to death, and changes in the medullary cytology after irradiation. The clinical picture of lethal radiation injury in swine is described. (authors) [French] Les auteurs rapportent les resultats d'une etude clinique et hematologique chez des porcs de race corse irradies in toto a dose sensiblement letale. Le but de cette etude etait de connaitre l'evolution du syndrome aigu d'irradiation chez le porc et de permettre ainsi le developpement d'experimentations ulterieures, en particulier dans le domaine therapeutique. La dose delivree etait de 285 rad (en dose absorbee au niveau du plan median vertical anteroposterieur. L'etude a porte essentiellement: 1. Sur les modifications cyclo-hematologiques du sang circulant immediatement apres l'irradiation, pour les differentes lignees cellulaires; l'evolution de ces modifications a ete notee jusqu'a la mort; 2. Sur les modifications de la cytologie medullaire apres irradiation (evolution du myelogramme et essai d'evaluation de la cellularite de la moelle osseuse);: 3. Sur les signes cliniques, d'ailleurs tres discrets, observes chez les porcs apres irradiation. (auteurs)

Reduced repair of potentially lethal radiation damage in glutathione synthetase-deficient human fibroblasts after X-irradiation

International Nuclear Information System (INIS)

Midander, J.; Revesz, L.; Deschavanne, P.J.; Debieu, D.; Malaise, E.P.

1986-01-01

Using a human fibroblast strain deficient in glutathione synthetase and a related proficient control strain, the role of glutathione (GSH) in repair of potentially lethal damage (PLD) has been investigated in determining survival by plating cells immediately or 24 h after irradiation. After oxic or hypoxic irradiation, both cell strains repair radiation-induced damage. However, under hypoxic conditions, the proficient cells repair PLD as well as under oxic conditions while the deficient cells repair less PLD after irradiation under hypoxic than under oxic conditions. Therefore, the oxygen enhancement ratio (o.e.r.) for proficient cells is similar whether the cells are plated immediately or 24 h later (2.0 and 2.13, respectively). In contrast, the o.e.r. for deficient cells is lower when the cells are plated 24 h after irradiation than when they are plated immediately thereafter (1.16 as compared to 1.55). The results indicate that GSH is involved in PLD repair and, in particular, in the repair of damage induced by radiation delivered under hypoxic conditions. (author)

Homogeneous immunoglobulins in the serum of irradiated and bone marrow reconstituted mice: the role of thymus and spleen

International Nuclear Information System (INIS)

Mink, J.G.; Radl, J.; Berg, P. van den; Muiswinkel, W.B. van; Oosterom, R. van.

1979-01-01

The influence of thymectomy and splenectomy on the frequency and class distribution of homogeneous immunoglobulins (H-Ig) in serum was studied in lethally irradiated (DBA/2 x C57B1/Rij)F 1 mice reconstituted with syngeneic bone marrow. During four follow-up periods in the first 9 months after transplantation, the sham-operated controls and splenectomized animals developed transient H-Ig in an average frequency of 14.2 and 15.7% respectively. There were no marked differences in the incidence of H-Ig within these two groups. In contrast, thymectomized mice and mice both thymectomized and splenectomized showed H-Ig in much higher frequencies (average percentages 31.6 and 36.5 respectively). The highest frequency of H-Ig was observed between 1.5 and 3.5 months after transplantation. H-Ig of the IgG1 and IgG2 subclasses were most frequent in all groups during the first 3.5 months. Later, H-Ig belonging to the IgM class also appeared in somewhat higher numbers. H-Ig of the IgA class was a very rare finding at any time. These results indicate that the presence of the thymus, but not necessarily of the spleen, is an important factor in the regulation of the immunoglobulin heterogeneity during the reconstitution of the immune system in lethally irradiated and bone marrow reconstituted mice. (author)

Induction of lethal and genetic damage by vacuum-ultraviolet (163 nm) irradiation of aqueous suspensions of yeast cells

International Nuclear Information System (INIS)

Ito, T.; Kobayashi, K.

1976-01-01

Yeast cells suspended in distilled water were irradiated with monochromatic 163 nm photons by immersing a specially designed discharge tube into the suspension. This was thought to be a useful means of investigating in vivo effects of radiation-induced water radicals on well cells in the complete absence of ionic species, since 163 nm photons can dissociate water only via excitation. These experiments showed that the water radicals (excluding e/sub aq/ - ) exerted both lethal and genetic (gene-conversion) effects quite potently, and the characteristic protection against these effects was observable when 2-mercaptoethanol or, in particular, p-aminobenzoic acid, a specific scavenger for OH radicals, was added to the medium prior to irradiation. Nearly complete protection from both lethal and genetic effects was observed in some cases with p-aminobenzoic acid. These results establish unequivocally that the OH radical, and not the hydrogen atom (H radical), possesses the damaging potency in the cell. Comparisons with γ-ray experiments revealed several differences between 163 nm photons and γ rays in the protective actions of radical scavengers, which may be attributable to reactive species other than OH radicals produced by the γ rays

Evidence of heritable lethal mutations in progeny of X-irradiated CHO cells by micronucleus count in clon-cells

International Nuclear Information System (INIS)

Hagemann, G.; Kreczik, A.; Treichel, M.

1996-01-01

Low doses of ionizing radiation reduce the growth rates of clones following irradiation of the progenitor cells. Such reductions of clone growth have been proven by means of measurements of clone size distributions. The medians of such distributions can be used to quantify the radiation damage. Prolongations of generation times and cell death as result of heritable lethal mutations have been discussed as causes for the reduction of clone growth. The cell number of a clone of hypotetraploid CHO-cells was compared to the frequency of micronucleated binucleated cells in the same clone using the cytokinesis-block-micronucleus method. The dose dependent reduction of clone sizes is measured by the difference of the medians (after log transformation) of the clone size distributions. At cytochalasin-B concentrations of 1 μg/ml and after an incubation time of 16 h a yield of binucleated cells of about 50% was obtained. Median clone size differences as a measure of clonal radiation damage increased linearly with incubation times of 76, 100, 124, and 240 h following irradiation with 3, 5, 7, and 12 Gy. The frequency of binucleated clone cells with micronuclei strongly increased with decreasing clone size by a factor up to 20 following irradiation with 3, 5, and 7 Gy. The frequency of micronucleated binucleated clone cells was found to be independent of incubation time after irradiation. Radiation induced clone size reductions result from cell losses caused by intraclonal expression of micronuclei which have its origin in heritable lethal mutations. Measurements of clone size distributions can be done automatically. They can serve as predictive test for determination of median cell loss rates of surviving cell clones. (orig./MG) [de

A quick method for testing recessive lethal damage with a diploid strain of Aspergillus nidulans

International Nuclear Information System (INIS)

Morpurgo, G.; Puppo, S.; Gualandi, G.; Conti, L.

1978-01-01

A simple method capable of detecting recessive lethal damage in a diploid strain of Aspergillus nidulans is described. The method scores the recessive lethals on the 1st, the 3rd and the 5th chromosomes, which represent about 40% of the total map of A. nidulans. Two examples of induced lethals, with ultraviolet irradiation and methyl methanesulfonate are shown. The frequency of lethals may reach 36% of the total population with UV irradiation. (Auth.)

Surgical, radio and immunotherapy of syngeneic tumors in mice

International Nuclear Information System (INIS)

Engel, B.

1982-01-01

In untreated DBA/2 and (57 Black 6 mice the growth of and formation of metastases by syngeneic tumors (L 1210, EL 4, P 815 respectively Lewis Lung) was tested to obtain hints regarding the subsequent treatment modalities. In summary it can be said that each tumor type has its specific behaviour as regards the formation of metastases. Tumor-carrying mice were then operated on respectively received radiotherapy at different lengths of time after the tumor cell transplantation. The results led to the conclusion that an early therapy increased the survival rates. These findings were taken as a basis for further experiments in which tumor-carrying mice were exclusively treated 24 hours after the tumor cell transplantation. It was found that tumor-carrying animals, as compared to untreated control animals, were cured by surgical measures. Radiotherapy was successful in cases of L 1210 and EL 4 tumors. Animals carrying P 815 and Lewis Lung tumors that were irradiated 24 hours after the tumor cell transplantation died of progressive tumor growth. (orig./MG) [de

Abnormal sensitivity of diploid skin fibroblasts from a family with Gardner's syndrome to the lethal effects of X-irradiation, ultraviolet light and mitomycin-C

International Nuclear Information System (INIS)

Little, J.B.; Nove, J.; Weichselbaum, R.R.

1980-01-01

Skin fibroblasts isolated from two members of the same family with the cancer-prone disease Gardner's Syndrome (intestinal polyposis, colon cancer, bone and soft tissue tumors) showed enhanced sensitivity to the lethal effects of X-irradiation, ultraviolet light and mitomycin-C. These cells showed no liquid-holding type recovery following UV-irradiation of confluent cultures, but were normal in their capacity for UV-induced unscheduled DNA synthesis. UV survival was not influenced by post-irradiation incubation with caffeine. (orig.)

Functional and morphological recovery of the T-cell compartment in lethally irradiated and reconstituted mice

International Nuclear Information System (INIS)

Kraal, G.; Hilst, B. van der; Boden, D.

1979-01-01

The recovery of the T-cell compartment in mice after lethal irradiation and reconstitution was studied using functional and morphological parameters. T-helper cell activity, determined by the direct SRBC-plaque-forming cell (PFC) response, recovered in a similar fashion as T-memory function which was studied by adoptive transfer of carrier-primed cells. Both functions returned to control levels in 2.5 to 3 months. Using immunoperoxidase staining of frozen sections with anti-T cell serum, the morphological recovery of the T-cell dependent areas in the white pulp of the spleen could be studied and compared with the functional recovery. (author)

Changes in rat liver and adipose tissue lipogenesis after single lethal X-irradiation: modification by the restricted food intake

International Nuclear Information System (INIS)

Sedlakova, A.; Ahlers, I.; Praslicka, M.

1981-01-01

Male rats of Wistar strain were adapted during a 4-week period to the nutritional regimes of meal feeding (MF) and ad libitum (AL) and were irradiated with the single whole-body lethal X-ray dose 14.35 Gy after 22 h of fasting. Within the intervals 1, 24, 48 and 72 h after irradiation lipogenesis changes in the liver were studied by measuring 1- 14 C-acetate incorporation (74 KBq) in the total lipids, fatty acids and cholesterol, and in the white adipose tissue pieces by measuring U- 14 C-glucose incorporation (74 KBq) in the total lipids, fatty acids and glyceride glycerol. Lipogenesis increased in the liver of the irradiated rats as compared with sham irradiated rats and reached the maximal values at 72 h after irradiation in AL animals and at 48 h after irradiation in MF animals. Lipogenesis in the adipose tissue decreased in the irradiated rats as compared with the sham irradiated ones and continued to decrease with the post-irradiation period. The adaptation to the nutritional regime of meal feeding markedly modified lipogenesis in the liver and the adipose tissue of the irradiated rats. Long-term fasting (before and after irradiation) was supposed to be another modifying factor in the lipogenesis changes. Lipogenesis changes in the liver depended on the MF nutritional regime. (author)

Changes in rat liver and adipose tissue lipogenesis after single lethal X-irradiation: modification by the restricted food intake

Energy Technology Data Exchange (ETDEWEB)

Sedlakova, A; Ahlers, I; Praslicka, M [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie

1981-01-01

Male rats of Wistar strain were adapted during a 4-week period to the nutritional regimes of meal feeding (MF) and ad libitum (AL) and were irradiated with the single whole-body lethal X-ray dose 14.35 Gy after 22 h of fasting. Within the intervals 1, 24, 48 and 72 h after irradiation lipogenesis changes in the liver were studied by measuring 1-/sup 14/C-acetate incorporation (74 KBq) in the total lipids, fatty acids and cholesterol, and in the white adipose tissue pieces by measuring U-/sup 14/C-glucose incorporation (74 KBq) in the total lipids, fatty acids and glyceride glycerol. Lipogenesis increased in the liver of the irradiated rats as compared with sham irradiated rats and reached the maximal values at 72 h after irradiation in AL animals and at 48 h after irradiation in MF animals. Lipogenesis in the adipose tissue decreased in the irradiated rats as compared with the sham irradiated ones and continued to decrease with the post-irradiation period. The adaptation to the nutritional regime of meal feeding markedly modified lipogenesis in the liver and the adipose tissue of the irradiated rats. Long-term fasting (before and after irradiation) was supposed to be another modifying factor in the lipogenesis changes. Lipogenesis changes in the liver depended on the MF nutritional regime.

Inhibitory action of chlorophyllin of autosome recessive lethals induced by irradiation; Accion inhibidora de la clorofilina de letales recesivos autosonicos inducidos por irradiacion

Energy Technology Data Exchange (ETDEWEB)

Salceda, V.M.; Pimentel, P.A.E.; Cruces, M.P. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: vmss@nuclear.inin.mx

2006-07-01

The chlorolin is a sodium salt of the chlorophyll that has a strong protective action of the damage induced by different agents so much physical as chemical. In Drosophila there is reported this effect in somatic cells. In contrast, in germinal cells using tests with the sexual chromosomes has not been found such inhibitory action. For this reason, in this occasion we will refer to the effect of the lethality induced in autosome chromosomes, in particular to the chromosome II of this species. For such effect groups of males of the line Canton-S its were pre-treated for 24h with or without 69 mm of CCS and later on treaties with or without 40 Gy of gamma irradiation. The males were then subjected to the technical Cy L / Pm for the detection of recessive lethals. In the third generation the respective counts of the descendant of each one of them to determine the corresponding categories for each extracted chromosome were made. To be mendelian crosses it is expected for a normal chromosome a proportion 2:1 of individuals with genotype Cy L / +: +/+. The absence of individuals +/+ it is indicative of a lethal gene, until 10% of these individuals of each male's total descendant, it is considered that is carrying of a semi lethal gene. The sum of lethal and semi lethals constitutes the category detrimental. The obtained results indicated that the pre-treatment with CCS reduces in a significant way the frequency of induced lethals by 40 Gy of gamma rays. The fact that an effect inhibitor has not been observed in the test of recessive lethal bound to the sex obtained previously, it contrasts with the effect observed in the chromosome II, results of this study and with the one observed in the chromosome III in somatic cells. The above-mentioned shows a differential action of the CCS between sexual chromosomes and autosomal before the effect of the gamma radiation. At the moment we don't have an explanation to these evidences. To evaluate the action of the

Inhibitory action of chlorophyllin of autosome recessive lethals induced by irradiation; Accion inhibidora de la clorofilina de letales recesivos autosonicos inducidos por irradiacion

Energy Technology Data Exchange (ETDEWEB)

Salceda, V M; Pimentel, P A.E.; Cruces, M P [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2006-07-01

The chlorolin is a sodium salt of the chlorophyll that has a strong protective action of the damage induced by different agents so much physical as chemical. In Drosophila there is reported this effect in somatic cells. In contrast, in germinal cells using tests with the sexual chromosomes has not been found such inhibitory action. For this reason, in this occasion we will refer to the effect of the lethality induced in autosome chromosomes, in particular to the chromosome II of this species. For such effect groups of males of the line Canton-S its were pre-treated for 24h with or without 69 mm of CCS and later on treaties with or without 40 Gy of gamma irradiation. The males were then subjected to the technical Cy L / Pm for the detection of recessive lethals. In the third generation the respective counts of the descendant of each one of them to determine the corresponding categories for each extracted chromosome were made. To be mendelian crosses it is expected for a normal chromosome a proportion 2:1 of individuals with genotype Cy L / +: +/+. The absence of individuals +/+ it is indicative of a lethal gene, until 10% of these individuals of each male's total descendant, it is considered that is carrying of a semi lethal gene. The sum of lethal and semi lethals constitutes the category detrimental. The obtained results indicated that the pre-treatment with CCS reduces in a significant way the frequency of induced lethals by 40 Gy of gamma rays. The fact that an effect inhibitor has not been observed in the test of recessive lethal bound to the sex obtained previously, it contrasts with the effect observed in the chromosome II, results of this study and with the one observed in the chromosome III in somatic cells. The above-mentioned shows a differential action of the CCS between sexual chromosomes and autosomal before the effect of the gamma radiation. At the moment we don't have an explanation to these evidences. To evaluate the action of the chlorophyllin on

Prolongation of rat islet allograft survival by direct ultraviolet irradiation of the graft

International Nuclear Information System (INIS)

Lau, H.; Reemtsma, K.; Hardy, M.A.

1984-01-01

Ultraviolet irradiation of rat dendritic cells completely abrogated their allostimulatory capacity in a mixed lymphocyte reaction. Rat islets of Langerhans similarly irradiated remained hormonally functional when transplanted into syngeneic diabetic rats. Allogeneic transplantation across a major histocompatibility barrier of islets initially treated in vitro with ultraviolet irradiation resulted in prolonged allograft survival without the use of any immunosuppressive agents

Ability of spleen cells from tumor bearing mice to transfer immunologic memory

Energy Technology Data Exchange (ETDEWEB)

Plavsic, B.; Jurin, M. (Zagreb Univ. (Yugoslavia)); Ugarkovic, B. (Institut Rudjer Boskovic, Zagreb (Yugoslavia))

1983-01-01

The ability of splenocytes from tumorous mice to transfer immunologic memory was tested. Three syngeneic experimental tumors from highly inbred strains were used; fibrosarcoma, lymphoma and Lewis lung carcinoma. Splenocytes from tumorous mice were collected after rejection of allogeneic skin which had been grafted at different stages of the tumor disease, and injected into lethally irradiated syngeneic recipients. These secondary hosts were grafted with the same allogeneic skin graft as their donors and the ability of cells transplanted from tumorous donors to transfer memory to allograft was tested. Tumorous mice seemed to have more memory cells (T lymphocytes) in their spleens than the controls.

Specific inhibition of cytotoxic memory cells produced against uv-induced tumors in uv-irradiation mice

International Nuclear Information System (INIS)

Thorn, R.M.

1978-01-01

Cytotoxic responses of uv-irradiated mice against syngeneic uv-induced tumors were measured by using a 51 Cr-release assay to determine if uv treatment induced a specific reduction of cytotoxic activity. The in vivo and in vitro primary responses against syngeneic tumors and allogeneic cells were unaffected, as was the ''memory'' response (in vivo stimulation, in vitro restimulation) against alloantigens. In contrast, the memory response of uv-treated mice against syngeneic, uv-induced tumors was consistently and significantly depressed. The cytotoxicity generated by tumor cell stimulation in vivo or in vitro was tumor-specific and T cell-dependent. Since the primary response against syngeneic uv-induced tumors produces apparently normal amounts of tumor-specific cytotoxic activity, uv-treated mice may not reject transplanted syngeneic tumors because of too few T effector memory cells. These results imply that, at least in this system, tumor rejection depends mostly on the secondary responses against tumor antigens and that at least one carcinogen can, indirectly, specifically regulate immune responses

Effect of syngeneic thymocytes on proliferation of the small intestinal epithelium in mice

International Nuclear Information System (INIS)

Shmakov, A.N.; Aparovich, G.G.; Trufakin, V.A.

1986-01-01

This paper describes the study of the action of syngeneic thymocytes on proliferation of the epithelium of the mouse small intestine. The mice were injected with 3 H-thymidine in the experiments. Under the experimental conditions presented here, syngeneic thymocytes can reduce the number of DNA-synthesizing cells in the intestinal epithelium, causing narrowing of the zone of proliferation and enlargement of the zone of differentiation of the enterocytes

Effect of serum from rats with destructed nuclei of the posterior hypothalamus on the formation of hemopoietic colonies in the spleen of lethally irradiated mice after bone marrow cell transplantation

International Nuclear Information System (INIS)

Fedorov, N.A.; Likhovetskaya, Z.M.; Kurbanova, G.N.; Prigozhina, T.A.; L'vovich, A.I.

1982-01-01

Colony formation capability of serum from animals with destructed nuclei of the posterior hypothalamus was studied in lethally irradiated mice. Male-rats of Wistar line and hybrid mice (CBA x C57 BL) were used in the experiments. The serum from rats with destructed nuclei of the posterior hypothalamus was injected simultaneously with bone marrow transplantation into lethally irradiated mice. The number of macrocolonies in the spleen was counted on the 9th day. It was ascertained that the serum from rats with destructed nuclei of the posterior hypothalamus caused an increase of the number of macroscopically visible colonies in the spleen of lethally irradiated mice. The determination of hemopoetic types of colonies showed that the effect of the serum from those animals caused an increase of the number of granulocytic-type colonies. The initiation of colony stimulating and leukopoetic activity in the blood of animals after the destruction of mammillary body nuclei and posterior hypothalamic nucleus attested, according to the authors point of view, that humoral mediators (humoral mediator) could participated in the mechanism of hypothalamus effect on leulopoiesis

Pluripotent stem cells with normal or reduced self renewal survive lethal irradiation

International Nuclear Information System (INIS)

Brecher, G.; Neben, S.; Yee, M.; Bullis, J.; Cronkite, E.P.

1988-01-01

Transfusion with 10,000 or 20,000 marrow cells resulted in 30+ days survival of 15%-50% of mice exposed to an Ld90 or LD100 or radiation. The use of congenic mice with alloenzyme markers permitted the identification of host and donor cells in the peripheral blood of transfused animals. Donor cells were present initially in all hosts. Between 55% and 92% of the animals became 100% host type by 12-24 weeks after transfusion in three separate experiments. To explore whether the temporary repopulation by donor cells was due to short-lived stem cells, the marrows of several primary hosts were transfused into secondary, lethally irradiated hosts. Some of the retransplanted primary donor and host cells persisted only temporarily. It is suggested that some of the donor stem cells in both the primary and secondary hosts had an intrinsically shortened life span

Identification of Paramecium bursaria syngens through molecular markers--comparative analysis of three loci in the nuclear and mitochondrial DNA.

Science.gov (United States)

Greczek-Stachura, Magdalena; Potekhin, Alexey; Przyboś, Ewa; Rautian, Maria; Skoblo, Inna; Tarcz, Sebastian

2012-09-01

This is the first attempt to resolve the phylogenetic relationship between different syngens of Paramecium bursaria and to investigate at a molecular level the intraspecific differentiation of strains originating from very distant geographical locations. Herein we introduce a new collection of five P. bursaria syngens maintained at St Petersburg State University, as the international collection of syngens was lost in the 1960s. To analyze the degree of speciation within Paramecium bursaria, we examined 26 strains belonging to five different syngens from distant and geographically isolated localities using rDNA (ITS1-5.8S-ITS2-5'LSU) fragments, mitochondrial cytochrome c oxidase subunit I (COI), and H4 gene fragments. It was shown that P. bursaria strains of the same syngens cluster together in all three inferred molecular phylogenies. The genetic diversity among the studied P. bursaria strains based on rDNA sequences was rather low. The COI divergence of Paramecium bursaria was also definitely lower than that observed in the Paramecium aurelia complex. The nucleotide sequences of the H4 gene analyzed in the present study indicate the extent of genetic differences between the syngens of Paramecium bursaria. Our study demonstrates the diagnostic value of molecular markers, which are important tools in the identification of Paramecium bursaria syngens. Copyright © 2011 Elsevier GmbH. All rights reserved.

The Effect of A Single Sub-Lethal Dose of Whole Body Irradiation on the Small Intestine of Rats

International Nuclear Information System (INIS)

Al-Ramli, M. A.; Kubba, M. A.; Al-Bassam, L. S.; Belhaj, K.; Al-shawish, N. M.

2007-01-01

The effect of whole body radiation with a single sub-lethal dose at 4 Gy on rat small intestine was studied histologically and quantitatively. Irradiated animals were euthanized at 24 hours, 3, 7, 14, 21 and 28 days post- irradiation. Crypts of Leiberkuhn and peyer's patches were especially targeted by irradiation. The crypts showed severe cellular fragmentation in the germinal cellular compartments twenty Four hours after irradiation resulting in partial denudation of villi especially at their Tips. At three days, these cells resumed their proliferative activity with the appearance of unusually large numbers of mitotic figures. Cellular regeneration in the crypts and on the villous surface showed improvement with advancing time till day 28 when the villi had complete epithelial covering and the proliferative activity of the germinal cryptic cells returned to normal. The quantitative study included the measurement of about fifty villi at each time after irradiation. A significant decrease in villous length was noticed at twenty four hours post-irradiation compared to the control values. The length of villi plateaued at about this level till day twenty one when it slightly increased to reach a sub normal mean length on day 28. We concluded that whole body irradiation with a single dose at 4 Gy was enough to induce cryptic cellular necrosis with sloughing of epithelial villous columnar covering. This cellular damage was, however, sub- total since quick regenerative cellular activity was noticed three days post-irradiation. The decrease in the villous length paralleled the cryptic cellular damage whereas full recovery was not achieved despite obvious cellular regeneration.

Role of marrow architecture and stromal cells in the recovery process of aplastic marrow of lethally irradiated rats parabiosed with healthy litter mates

International Nuclear Information System (INIS)

Hayashi, K.; Kagawa, K.; Awai, M.; Irino, S.

1986-01-01

Bone marrow aplasia was induced in rats by whole body lethal irradiation (1,000 rads by x-ray), and rats died of irradiation injury within 7 days. Correlative studies at light (LM), transmission (TEM) and scanning electron microscopy (SEM) demonstrated swelling of endothelial and reticular cells and hemorrhage due to detachment of sinus endothelial cells on days 1 and 2. With time, structural recovery occurred without hemopoietic recovery. Reticular cells developed small intracytoplasmic lipid droplets on days 3 and 4. This resulted in fatty aplastic marrow within 7 days. On the other hand, in the marrow of irradiated rats parabiosed with healthy mates by aortic anastomosis, hemopoiesis was initiated by adhesion of nucleated blood cells to fine cytoplasmic pseudopods of fat-stored cells on days 1 and 2 after parabiosis. On days 3 to 5, reticular cells with large lipid droplets and fine pseudopods increased, then hemopoietic foci became clear and extensive. On day 8 after parabiosis, the aplastic bone marrow recovered completely both its structure and hemopoietic activity. Thus, hemopoietic recovery in lethally irradiated marrow begins with recovery of vascular endothelial cells, re-establishment of sinusoidal structure, and morphological and functional recoveries of reticular cells from fat-storage cells by releasing intracytoplasmic lipid droplets. Marrow stromal cells, namely reticular, fat-storage and fibroblastoid cells, share a common cellular origin, and regain their structure and function when fat-storage cells and fibroid cells are placed in contact with hemopoietic precursor cells

Experiences in therapy for lethal midline granuloma

International Nuclear Information System (INIS)

Tosaka, Kaoru; Ishikawa, Takeru

1982-01-01

Four cases of the lethal midline granuloma or malignant granuloma of the nose were treated by irradiation and chemotherapy, which are generally prescribed for malignant lymphomas. Clinical, histological and laboratory examination indicated that they were the lethal midline granuloma and clearly differentiated from Wegener's granulomatosis or malignant lymphoma. All of the cases exhibited primary remission. The four cases were observed up to 38, 22, 14, and 10 months since the beginning of the therapy, showing no local or general recurrence. (author)

B-lymphocyte differentiation in lethally irradiated and reconstituted mice. II. Recovery of humoral immune responsiveness

International Nuclear Information System (INIS)

Rozing, J.; Brons, N.H.C.; Benner, R.

1977-01-01

The recovery of humoral immune responsiveness was studied in lethally irradiated, fetal liver-reconstituted mice. By means of both membrane fluorescence and antibody formation to sheep red blood cells (SRBC) as a functional assay, the rate of recovery of the compartments of B and T lymphocytes was determined in various lymphoid organs. The recovery of the immunoglobulin-positive (B) cell compartment after irradiation and reconstitution started in the spleen. This organ was also found to be the first in which the recovery of the B-cell population was completed. The interval between the recovery of the B-cell population in the spleen and that in the other organs tested was found to increase when the irradiated mice were reconstituted with spleen colony cells instead of fetal liver cells. This proved to be caused by the number and nature of the reconstituting hemopoietic stem cells. The immunoglobulin-positive (B) cells were found to appear before SRBC-reactive B cells could be demonstrated in spleen, lymph nodes, and Peyer's patches. The appearance of T lymphocytes in the various lymphoid organs required even more time. By means of cell transfer experiments, a sequential appearance of the precursors of anti-SRBC IgM-, IgG-, and IgA-plaque-forming cells could be demonstrated in spleen, bone marrow, lymph nodes, and Peyer's patches

IDENTIFICATION OF PARAMECIUM BURSARIA SYNGENS THROUGH MOLECULAR MARKERS – COMPARATIVE ANALYSIS OF MITOCHONDRIAL CYTOCHROME C OXIDASE SUBUNIT I (COI

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Patrycja Zagata

2014-08-01

Full Text Available The aim of this study is an identification of Paramecium bursaria syngens originating from different geographical locations and proving the correlation between distributions and belonging to any of five syngens. Ten strains of Paramecium bursaria belonging to five different syngens and strain of Paramecium multimicronucleatum were investigated using molecular marker — mitochondrial cytochrome c oxidase subunit I (COI. According to results, obtained in this study, using phylogenetic methods like Neighbor Joining (NJ and Maximum Likelihood (ML, relationship between analyzing strains through their clustering in clusters and correlation between strains belonging to any syngen and syngen’s distribution was confirmed. Phylograms constructed using NJ and ML methods revealed strains’ grouping in five clusters. Results which were obtained revealed usefulness of COI as a biomarker, which is important in identification of Paramecium bursaria syngens. This reports to a great potential of COI as a molecular marker and obtaining dependable results through combination of molecular methods with classical ones.

Action of caffeine on x-irradiated HeLa cells. V. Identity of the sector of cells that expresses potentially lethal damage in G1 and G2

International Nuclear Information System (INIS)

Beetham, K.L.; Tolmach, L.J.

1982-01-01

When HeLa S3 cells are irradiated in early G 1 with 4 Gy of 220-kV x rays and are then incubated in growth medium containing up to 5 mM caffeine, survival is reduced (as reported previously), reaching a concentration-dependent plateau. Cell killing presumably occurs as a result of the fixation of a portion of the potentially lethal damage the cells contain. These cells respond to continued treatment with caffeine at concentrations greater than 2 mM during S, but less so than during G 1 . When they reach G 2 arrest, however, extensive cell killing again occurs (reported previously), presumably also the result of potentially lethal damage fixation. G 1 -irradiated cultures that are treated with caffeine either continuously at a concentration in the range 1 to 5 mM, or at 10 mM for 8 hr and subsequently with the low concentration, achieve the same survival level in G 2 , provided that the potentially lethal damage is not repaired during G 1 and S. Repair seems to be completely inhibited in the presence of 3 to 4 mM caffeine. The results indicate that fixation of potentially lethal damage occurs in the same sector of cells in G 1 and G 2 , suggesting that the same cellular lesion gives rise to cell killing in the two phases

Interleukin 2 is not sufficient as helper component for the activation of cytotoxic T lymphocytes but synergizes with a late helper effect that is provided by irradiated T-region-incompatible stimulator cells

Energy Technology Data Exchange (ETDEWEB)

Reddehase, M.; Suessmith, W.; Moyers, C.; Falk, W.; Droege, W.

1982-01-01

Interleukin 2-containing supernatants from concanavalin A-activated spleen cells (CSCS) were found to provide strong helper activity for cytotoxic T lymphocyte (CTL) responses against allogeneic stimulator cells in microculture systems, but provided usually insufficient help for CTL responses against l-region compatible allogeneic or TNP-haptenated syngeneic stimulator cells. The interleukin 2-containing supernatant from HGG-activated AODH 7.1 hybridoma cells also mediated only relatively weak CTL responses against TNP-haptenated syngeneic cells in microcultures. Both types of supernatants, however, supported substantial responses against TNP-haptenated syngeneic stimulator cells if irradiated allogeneically activated syngeneic T cells or irradiated allogeneic spleen cells were added to the cultures. The allogeneic cells and the activated syngeneic T cells provided little helper activity if they were added in the absence of the interleukin 2-containing supernatants, thus demonstrating a synergistic effect between these 2 helper components. An l-region difference was sufficient for the helper effect of the allogeneic cells and control experiments showed that the presence of foreign l-region determinants could not be substituted for the TNP-haptenated stimulator cells.

Interleukin 2 is not sufficient as helper component for the activation of cytotoxic T lymphocytes but synergizes with a late helper effect that is provided by irradiated T-region-incompatible stimulator cells

International Nuclear Information System (INIS)

Reddehase, M.; Suessmith, W.; Moyers, C.; Falk, W.; Droege, W.

1982-01-01

Interleukin 2-containing supernatants from concanavalin A-activated spleen cells (CSCS) were found to provide strong helper activity for cytotoxic T lymphocyte (CTL) responses against allogeneic stimulator cells in microculture systems, but provided usually insufficient help for CTL responses against l-region compatible allogeneic or TNP-haptenated syngeneic stimulator cells. The interleukin 2-containing supernatant from HGG-activated AODH 7.1 hybridoma cells also mediated only relatively weak CTL responses against TNP-haptenated syngeneic cells in microcultures. Both types of supernatants, however, supported substantial responses against TNP-haptenated syngeneic stimulator cells if irradiated allogeneically activated syngeneic T cells or irradiated allogeneic spleen cells were added to the cultures. The allogeneic cells and the activated syngeneic T cells provided little helper activity if they were added in the absence of the interleukin 2-containing supernatants, thus demonstrating a synergistic effect between these 2 helper components. An l-region difference was sufficient for the helper effect of the allogeneic cells and control experiments showed that the presence of foreign l-region determinants could not be substituted for the TNP-haptenated stimulator cells

Sterilization and lethal gamma radiation doses on adults and eggs of Sitotroga Cerealella (OLIVIER)

International Nuclear Information System (INIS)

Wiendl, F.M.; Bovi, O.A.; Arthur, V.

1975-04-01

The influence of lethal doses of radiation from a cobalt 60 gamma source on eggs, adults and fertitility of Sitotroga Cerealella (Olivier) is described. Eggs irradiated with a dose of 14 Krad still showed viability of 16.1%. On longevity doses up to 70 Krad were usually non lethal but some variation could be observed related to the larval diet. Females fertilized by males irradiated with a dose of 70 Krad produced 36% fertile eggs. When the females were irradiated with the same dose, their fertility dropped to 2.2% and when both sexes were irradiated with a 60 Krad dose, the fertility was 28.8%

The entry of the prothymocyte into the thymus after lethal irradiation and bone marrow transplantation. 2

International Nuclear Information System (INIS)

Mulder, A.H.; Visser, J.W.M.; Zoetelief, J.; Bekkum, D.W. van

1988-01-01

The time of entry of prothymocytes into the thymus after lethal irradiation and bone marrow transplantation (BMT) was determined by exposing the thymus only or the whole body with the thymus shielded to a second irradiation after different intervals. The repopulation of the thymus by donor type cells was determined by a thymus repopulation assay using donor specific markers. Reirradiation of the thymus kills the prothymocytes that have entered the thymus during the interval. It was found that reirradiation of the thymus from 48 hours after BMT onwards increasingly delayed thymus regeneration. This shows that donor prothymocytes do not enter the thymus until about 2 days after BMT and that they continue to do so during at least 3 subsequent days. In the second reirradiation protocol thymus regeneration occurred earlier in the shielded thymus than in thymuses of whole body irradiated mice. Earlier thymus regeneration was not seen in mice that were reirradiated at 24 hours after BMT, but occurred only when irradiation took place at 48 hours and later. These data are consistent with those obtained in the first protocol. The results are in contradiction with results of direct homing experiments, which showed entrance of donor cells within 3 hours after BMT. A functional assay demonstrated that the early appearing cells cannot be prothymocytes. In retransplantation experiments it was shown that the bone marrow may indeed be the initial homing site of prothymocytes. 14 refs.; 5 figs.; 1 table

Frequencies of aneuploidy and dominant lethal mutations in young female mice induced by low dose γ-rays

International Nuclear Information System (INIS)

Yao Suyan; Zhang Chaoyang; Dai Lianlian; Gao Changwen

1991-01-01

Relationship between aneuploidy, dominant lethal mutations and doses in young feral mice induced by low dose γ-rays was examined. The results suggest that the frequencies of aneuploidy of embryos increased at 0.15 Gy, but increases at over 0.50 Gy after irradiation in groups. The frequencies of aneuploidy and dominant lethal mutations increased with increasing doses and fitted linear relationship. This dose-response relationship of trisomic was not significant. The frequency of dominant lethal mutations induced by 60 Co γ irradiation is 5.59%. The effect of dominant lethal mutation is higher than that of the aneuploidy

The effect of a single lethal X-irradiation exposure on the activity of lipoprotein lipase in the tissues of the rat

International Nuclear Information System (INIS)

Sedlakova, A.; Ahlers, I.; Praslicka, M.

1979-01-01

Wistar male rats, both fed and fasting for 16 h prior to irradiation, were exposed to a single lethal X-ray dose of 387 mC/kg (1500R). The activity of lipoprotein lipase in white adipose (epididymal) tissue and heart muscle and the concentration of serum triglycerides were determined at 1, 6, 24, 48, and 72 h after irradiation. In the early time periods, at 1 and 6 h after exposure, the activity of lipoprotein lipase decreased in adipose tissue and increased in heart muscle of the irradiated fed rats; in fasting rats it decreased in heart muscle at 1 h after exposure. The concentration of serum triglycerides increased at 1 h and decreased at 6 h after exposure in fed rats. In these rats, alterations in serum triglycerides correlated with changes in lipoprotein lipase activity in adipose tissue. Alterations observed at the later time periods were more dependent on the time interval between irradiation and the analysis. Lipoprotein lipase activity increased with time after irradiation up to the maximal values at 72 h. Fasting prior to and after irradiation substantially modified the response of animals to radiation. (author)

Relationship between chromosomal aberration of germ cells and dominant lethal mutation in male mice after low dosage of X-irradiation

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Mingdong, Wang; Baochen, Yang; Yuke, Jin [Bethune (N.) Medical Univ., Changchun, JL (China). Dept. of Gentics

1989-01-01

The relationship between chromosomal aberration adn dominant mutation in spermatocytes of late pachytene phase in male mice after a single X-irridiation was reported. It was found that the frequency of aberrant cells was correlative to the rate of fetal death, the latter was being about 2.5 times as high as the former. The frequency of dominant lethal mutation induced by X-irradiation is 2.1995x10{sup -3} gamete {center dot} 10 mGy.

Cross-immunity between syngeneic tumors in mice immunized with gamma-irradiated ascites tumors

International Nuclear Information System (INIS)

Kudo, Hajime; Waga, Takashi; Sato, Tatsusuke; Ogasawara, Masamichi; Ito, Izumi

1980-01-01

C3H/He mice immunized repeatedly with irradiated (13,000 rads 60 Co) MM46 or MM48, both transplantable ascites mammary carcinomas of the same strain, were subcutaneously challenged with the identical or the different tumor. In mice immunized with irradiated MM46, the growth of challenges of not only MM46 but also MM48 was inhibited. On the other hand, in mice immunized with irradiated MM48, the growth of challenges of MM48 was inhibited, but the inhibition of the growth of MM46 was not observed. Cross-immunity, therefore, was shown by immunization with MM46 but not with MM48. These findings were considered to indicate that MM46 expressed cross-immunity against MM48 because of its high resistance to the irradiation, and that MM48 did not show cross-immunity to MM46 because of its low resistance to the irradiation. (author)

Differentiation of bone marrow cells to functional T lymphocytes following implantation of thymus grafts and thymic stroma in nude and ATxBM mice

International Nuclear Information System (INIS)

Splitter, G.A.; McGuire, T.C.; Davis, W.C.

1977-01-01

Cardiac allografts were used to compare the immunologic capacity of nude mice and adult, thymectomized, lethally irradiated, bone marrow-reconstituted (AT x BM) mice. Neither nude nor AT x BM mice were able to reject cardiac allografts of any party. However, both rejected grafts of any party following implantation of neonatal thymus or thymus from 3-week-old syngeneic mice. Irradiated syngeneic thymus grafts (800 R) were equally effective in restoring host responsiveness against allografts. In contrast, allogeneic thymus grafts restored the capacity to reject second-party heart grafts only in AT x BM mice. Second-party grafts persisted indefintely when placed on nude mice implanted with an allogeneic, unirradiated thymus graft. Third-party grafts transplanted 17 weeks after reconstitution, however, were rejected. Irradiated nude mice given normal littermate bone marrow and simultaneously grafted with second-party thymus and heart allografts also failed to reject their second-party heart grafts. The difference in ultimate capacity to respond between AT x BM and nude mice suggests that a maturational defect exists in the nude mouse environment which impedes development of precursor T lymphocytes

Regeneration of hemopoietic precursor cells in spleen organ cultures from irradiated mice: influence of genotype of cells injected and of the spleen microenvironment

International Nuclear Information System (INIS)

von Melchner, H.; Lieschke, G.J.

1981-01-01

The regeneration of hemopoietic precursor cells (colony-forming cells, CFC) was monitored in spleen organ cultures from lethally irradiated mice injected with 10(7) normal syngeneic or allogeneic bone marrow cells. The important role of the microenvironment in supporting hemopoiesis was confirmed by the failure of mutant S1/S1d spleens to support CFC regeneration in organ cultures. However, the extent and quality of the CFC regeneration was clearly dependent on the genetic properties of the injected cells. Evidence for this was obtained from the regeneration patterns of various CFC types in organ cultured spleens derived from different mouse donor-recipient strain combinations (CBA/CBA, CBA/C57BL, CBA/BALB/c, C57BL/C57BL, C57BL/CBA, C57BL/BALB/c) that maintained the differences in the bone marrow frequency of various CFC types characteristic of the donor strain

Novel synthetic lethality screening method identifies TIP60-dependent radiation sensitivity in the absence of BAF180.

Science.gov (United States)

Hopkins, Suzanna R; McGregor, Grant A; Murray, Johanne M; Downs, Jessica A; Savic, Velibor

2016-10-01

In recent years, research into synthetic lethality and how it can be exploited in cancer treatments has emerged as major focus in cancer research. However, the lack of a simple to use, sensitive and standardised assay to test for synthetic interactions has been slowing the efforts. Here we present a novel approach to synthetic lethality screening based on co-culturing two syngeneic cell lines containing individual fluorescent tags. By associating shRNAs for a target gene or control to individual fluorescence labels, we can easily follow individual cell fates upon siRNA treatment and high content imaging. We have demonstrated that the system can recapitulate the functional defects of the target gene depletion and is capable of discovering novel synthetic interactors and phenotypes. In a trial screen, we show that TIP60 exhibits synthetic lethality interaction with BAF180, and that in the absence of TIP60, there is an increase micronuclei dependent on the level of BAF180 loss, significantly above levels seen with BAF180 present. Moreover, the severity of the interactions correlates with proxy measurements of BAF180 knockdown efficacy, which may expand its usefulness to addressing synthetic interactions through titratable hypomorphic gene expression. Copyright © 2016. Published by Elsevier B.V.

Modification of the repair of potentially lethal damage in plateau-phase Chinese hamster cells by 2-chlorodeoxyadenosine

International Nuclear Information System (INIS)

Tanabe, Kiyoshi; Hiraoka, Wakako; Kuwabara, Mikinori; Matsuda, Akira; Ueda, Tohru; Sato, Fumiaki.

1988-01-01

The ability of 2-chlorodeoxyadenosine, a ribonucleotide reductase inhibitor, to inhibit the repair of potentially lethal damage was demonstrated in Chinese hamster V79 cells after X irradiation in plateau-phase cultures. This ability of the drug was completely diminished when deoxycytidine was added at the same time, though this was slightly affected by the addition of adenosine, suggesting that this drug was phosphorylated by deoxycytidine kinase to serve as an inhibitor of the repair of potentially lethal damage. Compared with hydroxyurea, another ribonucleotide reductase inhibitor, this drug appeared to contain its own activity which suppressed the repair of potentially lethal damage. A combined study of post-irradiation treatment with hypertonic salt solution and with this drug on the fixation of potentially lethal damage revealed that this drug inhibited the repair of hypertonic-insensitive potentially lethal damage. (author)

Modification of the repair of potentially lethal damage in plateau-phase Chinese hamster cells by 2-chlorodeoxyadenosine

Energy Technology Data Exchange (ETDEWEB)

Tanabe, Kiyoshi; Hiraoka, Wakako; Kuwabara, Mikinori; Matsuda, Akira; Ueda, Tohru; Sato, Fumiaki.

1988-09-01

The ability of 2-chlorodeoxyadenosine, a ribonucleotide reductase inhibitor, to inhibit the repair of potentially lethal damage was demonstrated in Chinese hamster V79 cells after X irradiation in plateau-phase cultures. This ability of the drug was completely diminished when deoxycytidine was added at the same time, though this was slightly affected by the addition of adenosine, suggesting that this drug was phosphorylated by deoxycytidine kinase to serve as an inhibitor of the repair of potentially lethal damage. Compared with hydroxyurea, another ribonucleotide reductase inhibitor, this drug appeared to contain its own activity which suppressed the repair of potentially lethal damage. A combined study of post-irradiation treatment with hypertonic salt solution and with this drug on the fixation of potentially lethal damage revealed that this drug inhibited the repair of hypertonic-insensitive potentially lethal damage.

Constant post-irradiation repopulation rates and linear relationship between cellular blood response and number of transplanted bone marrow cells in inbread mice

International Nuclear Information System (INIS)

Petersen, B.H.

1977-01-01

Graded doses of syngeneic bone marrow cells were transplanted into lethally irradiated mice. Repopulation curves of peripheral blood granulocytes and platelets were apparently exponential and parallel after doses larger than 5 x 10 5 cells. The blood platelet sub(d) was reduced from 111 h to 53-57 h, and granulocyte Tsub(d) from 57 to 40 h in transplanted groups. The mean blood cell counts were reproducible to be used as a biological assay of the amount of bone marrow cells transplanted. Linear relationship between increment of blood cells up to day 16 and number of bone marrow cells transplanted on day 1 was demonstrated (1,200 granulocytes and 14,300 platelets/μl blood per 10 5 bone marrow cells). The linearity suggested a mean Tsub(d) < 22.5 h of proliferating bone marrow cells, and allowed a rough estimation of mouse bone marrow stem cell radiosensitivity (Dsub(o) 76 rad). (author)

Mechanisms of immunological eradication of a syngeneic guinea pig tumor: participation of a component(s) of recipient origin in the expression of systemic adoptive immunity

International Nuclear Information System (INIS)

Shu, S.; Fonseca, L.S.; Kato, H.; Zbar, B.

1983-01-01

The effects of carrageenan and trypan blue on the expression of adoptive immunity to the syngeneic guinea pig line 10 hepatoma were investigated. Adoptive immunity was assessed by observing dermal tumor growth in recipients of immune cells and by bioassays in which tumor challenge sites were transplanted into secondary hosts. Carrageenan abrogated transferred immunity in treated animals as evidenced by dermal tumor growth and by development of fatal ascites tumors in peritoneal cavities of the secondary hosts. Trypan blue, on the other hand, did not abrogate transferred immunity in treated animals. However, the i.p. bioassay revealed the presence of line 10 cells in the tumor challenge sites 10 days after adoptive transfer. In vitro and in vivo exposure of immune spleen cells to carrageenan or trypan blue had no significant effect on the subsequent adoptive transfer, indicating that the inhibitory activity of these agents cannot be attributed to direct toxicity to immune lymphoid cells. Tumor challenge sites taken from carrageenan or trypan blue-treated animals 5 days after adoptive transfer failed to grow progressively when transplanted s.c. into secondary hosts. This observation suggests the presence of immune cells at tumor challenge sites. Thus, the inhibitory effects were unlikely due to interference with recirculation of the i.v.-transferred immune cells. Adoptive immunity was not influenced in guinea pigs that received a lethal dose of irradiation (500 rads). These results demonstrate that a recipient component(s) sensitive to carrageenan and trypan blue but resistant to radiation is essential to the expression of adoptive immunity

Prophylactic immunization against experimental leishmaniasis. III. Protection against fatal Leishmania tropica infection induced by irradiated promastigotes involves Lyt-1+2- T cells that do not mediate cutaneous DTH

International Nuclear Information System (INIS)

Liew, F.Y.; Howard, J.G.; Hale, C.

1984-01-01

Protective immunity against fatal L. tropica infection in genetically vulnerable BALB/c mice can be induced by prophylactic immunization with irradiated promastigotes even when heat-killed. Such immunity is adoptively transferable transiently into intact or durably into sub-lethally irradiated (200 or 550 rad) syngeneic recipients by splenic T but not B cells. The effector T cells are of the Lyt-1 + 2 - phenotype, devoid of demonstrable cytotoxic activity. The immune splenic T cell population expresses specific helper activity for antibody synthesis. A causal role for helper T cells in this capacity, however, seems unlikely, because it was shown that antibody does not determine the protective immunity against L. tropica. The immunized donors show no detectable cutaneous DTH or its early memory recall in response to live or killed promastigotes or a soluble L. tropica antigen preparation. Spleen, lymph node, and peritoneal exudate cells from protectively immunized donors similarly fail to transfer DTH locally or systemically. These cells also lack demonstrable suppressive activity against the expression or induction of DTH to L. tropica. Thus, protection against L. tropica induced by prophylactic i.v. immunization with irradiated promastigotes appears to be conferred by Lyt-1 + 2 - T cells that are distinguishable from T cells mediating either both DTH and T help, or cytotoxicity

Hematologic syndrome in man modeled from mammalian lethality

International Nuclear Information System (INIS)

Jones, T.D.

1981-01-01

Data on acute radiation lethality due to failure of the hematologic system in rats, mice, dogs, swine, monkeys and man are analyzed. Based on the available data, the mortality incidences for 1-100% levels can be computed directly if one has only an estimate of the dose lethal to 50% of the population (LD 50 ) for the mammalian strain and radiation environment of interest. The sole restriction is that the dose profile to the marrow be moderately uniform. If an LD 50 for any exposure situation has been measured, then one can readily scale to any desired situation through implicit-biological and empirical-physical relationships. The LD 50 for man, exposed to an isotropic cloud of photons, and knowledge of the bone-marrow dose profiles readily permit evaluation of the model for other levels of human mortality from different irradiating particles, partial body irradiation and spatially dependent and/or mixed radiation environments. (author)

Potentiation of radiation lethality by Topotecan, a Topoisomerase I inhibitor

International Nuclear Information System (INIS)

Lamond, J.P.; Kinsella, T.J.; Boothman, D.A.

1995-01-01

Purpose/Objective: Topotecan is a water soluble Topoisomerase I (Topo I) inhibitor that has demonstrated antineoplastic activity in phase I/II trials of solid tumors (such as non-small cell lung, small cell lung, ovarian, esophageal and head and neck primaries) and leukemias. We sought to determine (1) if Topotecan potentiated the lethal effects of ionizing radiation, and (2) the characteristics of the synergistic effect. Materials and Methods: Human radioresistant melanoma (U1-Mel) and glioma (D54) cells were grown in Dulbecco's modified Eagle's medium (DME) with 10% fetal calf serum (FCS) until confluence-arrest. Cells were x-irradiated (0-700 cGy) and exposed to various Topotecan concentrations (2-100μM), either before (for 4 hours), during, or after (for 4 hours) irradiation. Appropriate controls were also performed. Survival was determined via colony forming assays. Survival curves were normalized to correct for drug cytotoxicities and variations in initial viable cells plated. In another set of experiments, U1-Mel cells were exposed to 10 μM Topotecan either before, during or after 400 cGy, as described above. A modification of the SDS and KCl assay was used to quantify Topo I-DNA complexes via glass fiber filter binding. All experiments were performed at least 7 times in duplicate. Results: Potentiation of radiation lethality was seen in the U1-Mel and D54 cell lines. The synergistic effects were (1) dependent on drug concentration, with lethality enhancement and minimal drug lethality alone in the 2-10 μM range (2) dependent on timing, with synergy present only when the drug was present at the time of, or shortly after irradiation, and (3) irreversible, with inhibition of potential lethal damage repair (PLDR). The dose enhancement ratios (DER) for 4 μM Topotecan in the U1-Mel cells was 1.7 - 2.4, depending on the survival endpoints that were used. The DER for 2 μM Topotecan in D54 cells was 3.0 - 4.0. The U1-Mel cells that were exposed to Topotecan

Mutagenic effects of irradiated glucose in Drosophila melanogaster

International Nuclear Information System (INIS)

Varma, M.B.; Rao, K.P.; Nandan, S.D.; Rao, M.S.

1982-01-01

The mutagenic effects of irradiated glucose were studied using the sex-linked recessive lethal test in Drosophila melanogaster. Oregon K males of D. melanogaster reared on a medium containing 20 or 40% glucose irradiated with a dose of 0.02, 0.10, 0.20, 2 or 5 Mrad #betta#-rays were scored for the induction of sex-linked recessive lethals. The results showed no significant increase in the frequency of X-lethals in Drosophila at any of the dose levels. (author)

Rifaximin diminishes neutropenia following potentially lethal whole-body radiation.

Science.gov (United States)

Jahraus, Christopher D; Schemera, Bettina; Rynders, Patricia; Ramos, Melissa; Powell, Charles; Faircloth, John; Brawner, William R

2010-07-01

Terrorist attacks involving radiological or nuclear weapons are a substantial geopolitical concern, given that large populations could be exposed to potentially lethal doses of radiation. Because of this, evaluating potential countermeasures against radiation-induced mortality is critical. Gut microflora are the most common source of systemic infection following exposure to lethal doses of whole-body radiation, suggesting that prophylactic antibiotic therapy may reduce mortality after radiation exposure. The chemical stability, easy administration and favorable tolerability profile of the non-systemic antibiotic, rifaximin, make it an ideal potential candidate for use as a countermeasure. This study evaluated the use of rifaximin as a countermeasure against low-to-intermediate-dose whole-body radiation in rodents. Female Wistar rats (8 weeks old) were irradiated with 550 cGy to the whole body and were evaluated for 30 d. Animals received methylcellulose, neomycin (179 mg/kg/d) or variably dosed rifaximin (150-2000 mg/kg/d) one hour after irradiation and daily throughout the study period. Clinical assessments (e.g. body weight) were made daily. On postirradiation day 30, blood samples were collected and a complete blood cell count was performed. Animals receiving high doses of rifaximin (i.e. 1000 or 2000 mg/kg/d) had a greater increase in weight from the day of irradiation to postirradiation day 30 compared with animals that received placebo or neomycin. For animals with an increase in average body weight from irradiation day within 80-110% of the group average, methylcellulose rendered an absolute neutrophil count (ANC) of 211, neomycin rendered an ANC of 334, rifaximin 300 mg/kg/d rendered an ANC of 582 and rifaximin 1000 mg/kg/d rendered an ANC of 854 (P = 0.05 for group comparison). Exposure to rifaximin after near-lethal whole-body radiation resulted in diminished levels of neutropenia.

Influence Of Quinolone Lethality on Irradiated Anaerobic Growth of Escherichia Coli

International Nuclear Information System (INIS)

Ibrahim, I.M.; El-Kabbany, H.M.; El-Esseily, E.SH.

2012-01-01

Bacteriostatic and bactericidal activities were measured with wild type cells and isomerase mutants of Escherichia coli for ciprofloxacin, formation of quinolone-gyrase-DNA complexes, observed as a sodium dodecyl sulfate (SDS) dependent drop in cell lysate viscosity, occurred during aerobic and anaerobic growth and in the presence and in the absence of chloramphenicol. Quinolone activity against Escherichia coli was examined during aerobic growth, aerobic treatment with chloramphenicol, and anaerobic growth. Nalidixic acid, norfloxacin and ciprofloxacin were lethal for cultures growing aerobically, and the bacteriostatic activity of each quinolone was unaffected by anaerobic growth. However, lethal activity was distinct for each quinolone with cells treated aerobically with chloramphenicol or grown anaerobically. Nalidixic acid failed to kill cells under both conditions, norfloxacin killed cells when they were grown anaerobically but not when they were treated with chloramphenicol, ciprofloxacin killed cells under both conditions but required higher concentrations than those required with cells grown aerobically, C-methoxy fluoro quinolone was equally lethal under all conditions. However, lethal chromosome fragmentation, detected as a drop in viscosity in the absence of SDS, was occurred with nalidixic acid treatment only under aerobic conditions in the absence of chloramphenicol, thus, all quinolones tested appeared to form reversible bacteriostatic complexes containing broken DNA during aerobic growth, during anaerobic growth, and when protein synthesis is blocked. The ability to fragment chromosomes rapidly kill cells under these conditions depends on quinolone structure. The radiation of sublethal dose was 3 Gy at rate of 0.6 Gy/min was shown as non-significant result

A linear-quadratic model of cell survival considering both sublethal and potentially lethal radiation damage

International Nuclear Information System (INIS)

Rutz, H.P.; Coucke, P.A.; Mirimanoff, R.O.

1991-01-01

The authors assessed the dose-dependence of repair of potentially lethal damage in Chinese hamster ovary cells x-irradiated in vitro. The recovery ratio (RR) by which survival (SF) of the irradiated cells was enhanced increased exponentially with a linear and a quadratic component namely ζ and ψ: RR=exp(ζD+ψD 2 ). Survival of irradiated cells can thus be expressed by a combined linear-quadratic model considering 4 variables, namely α and β for the capacity of the cells to accumulate sublethal damage, and ζ and ψ for their capacity to repair potentially lethal damage: SF=exp((ζ-α)D+ (ψ-β)D 2 ). author. 26 refs.; 1 fig.; 1 tab

The effects of radiation dose-rate and quality on the induction of dominant lethals in mouse spermatids

International Nuclear Information System (INIS)

Searle, A.G.; Beechey, G.V.

1981-01-01

Hybrid male mice were given 3 Gy (300 rad) doses of X- or γ-irradiation at dose-rates of either 0.6 or 0.002 Gy/min for each radiation. Germ-cells treated as spermatids were tested for dominant lethality. Effects on spermatogonia were evaluated by studying testis-weight, sperm-count and sperm abnormalities. The rate of induction of dominant lethal mutations was 2.1 times as high after acute X-irradiation as after protracted γ-irradiation. Most of this difference resulted from the change in radiation quality, since the relative effectiveness of X- versus γ-irradiation was 1.9 at low and 1.6 at high dose rates. For each radiation, however, fewer dominant lethals were induced at low dose-rates than at high (low/high ratios of 0.8 and 0.9 respectively) although differences did not reach a significant level. There were no statistically significant effects of dose rate on testis-weight of sperm-count in the X-ray series, but there were significantly less severe effects on both with protraction of the γ-irradiation. Evidence for effects of radiation quality on these characters was conflicting. Frequencies of abnormal spermatozoa were markedly increased 7 weeks after irradiation but there were no consistent effects of radiation intensity or quality. (orig.)

Ultraviolet-B lethal damage on Pseudomonas aeruginosa

International Nuclear Information System (INIS)

Degiorgi, C.F.; Fernandez, R.O.; Pizarro, R.A.

1996-01-01

Pseudomonas aeruginosa has shown an increased sensitivity compared with that of Escherichia coli and Enterobacter cloacae, when they were exposed to 0.4 kJ/m2 of ultraviolet-B radiation. The rapid decay in cell viability observed in Pseudomonas aeruginosa after the irradiation was influenced by factors such as culture media and the presence of pyocyanine during the irradiation. The radioinduced lethal damage could be prevented by photoreactivating treatment, indicating that pyrimidine dimer formation was the mechanism causing bacterial death. The results indicate that several environmental conditions may act as protective agents against ultraviolet-B-induced damage

Syngeneic peripheral blood stem cell transplantation with immunosuppression for hepatitis-associated severe aplastic anemia

Directory of Open Access Journals (Sweden)

Aleksandar Savic

2010-12-01

Full Text Available Hepatitis-associated aplastic anemia occurs in up to 10% of all aplastic anemia cases. Syngeneic bone marrow transplantation is rare in patients with severe aplastic anemia and usually requires pre-transplant conditioning to provide engraftment. We report on a 29-year-old male patient with hepatitis-associated severe aplastic anemia who had a series of severe infectious conditions before transplantation, including tracheal inflammation. Life-threatening bleeding, which developed after bronchoscopy, was successfully treated with activated recombinant factor VII and platelet transfusions. Syngeneic peripheral blood stem cell transplantation using immunosuppressive treatment with antithymocyte globulin and cyclosporin A without high-dose pre-transplant conditioning was performed, followed by complete hematologic and hepatic recovery.

Protection of melanized Cryptococcus neoformans from lethal dose gamma irradiation involves changes in melanin's chemical structure and paramagnetism.

Directory of Open Access Journals (Sweden)

Abdelahad Khajo

Full Text Available Certain fungi thrive in highly radioactive environments including the defunct Chernobyl nuclear reactor. Cryptococcus neoformans (C. neoformans, which uses L-3,4-dihydroxyphenylalanine (L-DOPA to produce melanin, was used here to investigate how gamma radiation under aqueous aerobic conditions affects the properties of melanin, with the aim of gaining insight into its radioprotective role. Exposure of melanized fungal cell in aqueous suspensions to doses of γ-radiation capable of killing 50 to 80% of the cells did not lead to a detectable loss of melanin integrity according to EPR spectra of melanin radicals. Moreover, upon UV-visible (Xe-lamp illumination of melanized cells, the increase in radical population was unchanged after γ-irradiation. Gamma-irradiation of frozen cell suspensions and storage of samples for several days at 77 K however, produced melanin modification noted by a reduced radical population and reduced photoresponse. More direct evidence for structural modification of melanin came from the detection of soluble products with absorbance maxima near 260 nm in supernatants collected after γ-irradiation of cells and cell-free melanin. These products, which include thiobarbituric acid (TBA-reactive aldehydes, were also generated by Fenton reagent treatment of cells and cell-free melanin. In an assay of melanin integrity based on the metal (Bi(+3 binding capacity of cells, no detectable loss in binding was detected after γ-irradiation. Our results show that melanin in C. neoformans cells is susceptible to some damage by hydroxyl radical formed in lethal radioactive aqueous environments and serves a protective role in melanized fungi that involves sacrificial breakdown.

A Study on Recovery from Potentially Lethal Damage induced by γ-Irradiation in Plateau-phase Vero Cells in vitro

International Nuclear Information System (INIS)

Kim, Il Han; Choi, Eun Kyung; Ha, Sung Whan; Park, Charn Il; Cha, Chang Yong

1988-01-01

Recovery from potentially lethal damage (PLDR) after irradiation was studied in plateau-phase culture of Vero cells in vitro. Unfed plateau-phase cells were irradiated with dose of 1 to 9 Gy using Cs-137 irradiator. Cells then were incubated again and left in situ for 0, 1, 2, 3, 4, 5, 6 and 24 hours and then were trypsinized, explanted, and subcultured in fresh RPMI-1640 media containing 0.33% agar. Cell survival was measured by colony forming ability. An adequate number of heavily irradiated Vero cells were added as feeder cells to make the total cell number constant in every culture dish. As the postirradiation in situ incubation time increased, surviving fraction increased saturation level at 2 to 4 hours after in situ incubation. As the radiation dose increased, the rate of PLDR also increased. In analysis of cell survival curve fitted to the linear-quadratic model, the linear inactivation coefficient (a) decreased largely and reached nearly to zero but the quadratic inactivation coefficient (b) increased minimally by increment of postirradiation in situ incubation time. So PLDR mainly affected the damage expressed as a. In the multitarget model, significant change was not obtained in D0 but in Dq. Therefore, shoulder region in cell survival curve was mainly affected by PLDR and terminal slope was not influenced at all. And dose-modifying factor by PLDR was relatively higher in shoulder region, that is, in low dose area below 3 Gy

A novel challenge test incorporating irradiation (60Co) of compost sub-samples to validate thermal lethality towards pathogenic bacteria.

Science.gov (United States)

Moore, John E; Watabe, Miyuki; Stewart, Andrew; Cherie Millar, B; Rao, Juluri R

2009-01-01

Maturing compost heaps normally attaining temperatures ranging from 55 to 65 degrees C is generally regarded to conform to recommended biological risks and sanitation standards for composts stipulated by either EU or US-EPA. Composted products derived from animal sources are further required by EU biohazard safety regulatory legislation that such composts either attain 70 degrees C for over 3h during maturation or via treatment at 70 degrees C for 1h before being considered for dispensation on land. The setting of the upper limit of thermal lethality at 70 degrees C/1h for achieving biosecurity of the animal waste composted products (e.g. pelleted fertilizer formulations) is not properly substantiated by specific validation tests, comprising a 'wipe-out' step (usually via autoclaving) followed by inoculation of a prescribed bacterium, exposure to 70 degrees C/1h and the lethality determined. Pelleted formulations of composts are not amenable for wet methods (autoclaving) for wipe-out sterilization step as this is detrimental to the pellet and compromises sample integrity. This study describes a laboratory method involving the employment of ((60)Co) irradiation 'wipe-out' step to: (a) compost sub-samples drawn from compost formulation heaps and (b) pelleted products derived from composted animal products while determining the thermal lethality of a given time/temperature (70 degrees C/1h) treatment process and by challenging the irradiated sample (not just with one bacterium but), out with 10 potential food-poisoning organisms from the bacterial genera (Campylobacter, Escherichia, Listeria, Salmonella, Yersinia) frequently detected in pig and poultry farm wastes. This challenge test on compost sub-samples can be a useful intervention ploy for 'inspection and validation' technique for composters during the compost maturity process, whose attainment of temperatures of 55-65 degrees C is presumed sufficient for attainment of sanitation. Stringent measures are further

Contribution to the study of non-lethal whole-body gamma irradiation effects on the unitary activities of the dorsal hippocampus in rabbits

International Nuclear Information System (INIS)

Bassant, M.-H.

1976-01-01

The effects of non-lethal whole-body gamma irradiation on the spontaneous activity of the dorsal hippocampus pyramidal cells were studied in rabbits. First of all the unitary activity of the CA 1 and CA 4 pyramidal cells was recorded extracellularly in the reference animal. The results were analyzed by a statistical method. By classifying the various cell functioning modes observed, and measuring the frequency with which they appear as a function of the state of vigilance, an attempt was made to characterize precisely the spontaneous activity of the hippocampal neurons. Recording were then made under identical experimental conditions on animals totally irradiated to mean absorbed doses of 250 and 450 rads (delivered at a constant rate of 14 rads/mn). The electroencephalographic activity of the hippocampus shows many anomalies (slow waves, wave-points, theta rythm deformation) as a function of which several pathological states were distinguished and used to classify the data, then processed by the methods already used for the reference data. The results obtained prove that the statistical characteristics of the unitary activity are changed by irradiation [fr

Indirect effects are involved in the production of potentially lethal damage in X irradiated escherichia coli

International Nuclear Information System (INIS)

Billen, D.

1985-01-01

When living cells are exposed to low LET radiation, 60 to 70% of the resulting lethality is said to be due to indirect effects. Using the OH radical scavengers: glycerol n-butanol, t-butanol, and NO/sub 2//sup -/. The authors observed that a radiosensitive E. coli K-12 mutant (W 3110 thy/sup -/ polAl/sup -/) lacking DNA polymerase 1 displays a markedly enhanced radioresistance when exposed to X rays in the presence of these chemicals. The extent of protection afforded by these chemicals correlated with their OH radical scavenging ability over the limited range of concentrations of the chemicals studied. (Only non-toxic concentrations of the chemicals were used). The presence of 2M glycerol during irradiation of the PolAl/sup -/ cells results in a survival level higher than that seen for the unprotected parent strain (W 3110 thy polA/sup +/)

Antiviral T cell competence and restriction specificity of mixed allogeneic (P1 + P2----P1) irradiation chimeras

International Nuclear Information System (INIS)

Rueedi, E.S.; Sykes, M.; Ildstad, S.T.; Chester, C.H.; Althage, A.; Hengartner, H.; Sachs, D.H.; Zinkernagel, R.M.

1989-01-01

Mixed irradiation bone marrow chimeras were prepared by reconstituting lethally irradiated C57BL/10 (B10) or B10.D2 mice with T cell-depleted bone marrow cells of B10 plus B10.D2 origin. These chimeras were healthy and survived well under conventional housing conditions and after experimental laboratory infections. Of a total of 17 chimeras tested, 2 died spontaneously or from the injected virus. Twelve of fifteen chimeras mounted a measurable cytotoxic T cell response to virus. Despite approximately equal percentages of B10 and B10.D2 lymphocytes in chimeras, cytotoxic T cell responses to vaccinia virus and lymphocytic choriomeningitis virus were mediated variably by either syngeneic or allogeneic donor lymphocytes; thus the H-2 type of effector T cells frequently did not correspond to the 50:50 distribution of spleen or peripheral blood lymphocytes. Cytotoxic responses were restricted exclusively to recipient H-2 type. All mixed chimeras examined were able to mount a good IgG response to vesicular stomatitis virus. These results confirm previous data suggesting that such mixed chimeras are healthy and immunocompetent and demonstrate strict recipient-determined restriction specificity of effector T cells; they also suggest that if T help is necessary for induction of virus-specific cytotoxic T cells, it does not require host-restricted interactions between helper T cells and precursor cytotoxic T cells

Molecular Identification of Paramecium bursaria Syngens and Studies on Geographic Distribution using Mitochondrial Cytochrome C Oxidase Subunit I (COI).

Science.gov (United States)

Zagata, Patrycja; Greczek-Stachura, Magdalena; Tarcz, Sebastian; Rautian, Maria

2015-01-01

Paramecium bursaria is composed of five syngens that are morphologically indistinguishable but sexually isolated. The aim of the present study was to confirm by molecular methods (analyses of mitochondrial COI) the identification of P. bursaria syngens originating from different geographical locations. Phylograms constructed using both the neighbor-joining and maximum-likelihood methods based on a comparison of 34 sequences of P. bursaria strains and P. multimicronucleatum, P. caudatum and P.calkinsi strains used as outgroups revealed five clusters which correspond to results obtained previously by mating reaction. Our analysis shows the existence of 24 haplotypes for the COI gene sequence in the studied strains. The interspecies haplotype diversity was Hd = 0.967. We confirmed genetic differentiation between strains of P. bursaria and the occurrence of a correlation between geographical distribution and the correspondent syngen.

Derangement of cellular plasma membranes due to non-lethal radiation doses

International Nuclear Information System (INIS)

Koeteles, G.J.; Kubasova, T.; Somosy, Z.; Horvath, L.

1983-01-01

Earlier observations in the laboratory on fibroblasts and various blood cells of animal and human origins pointed to alteration of concanavalin A binding sites of plasma membranes as well as to concomitant morphological changes and scanning electron microscopic appearance of cell surfaces following sub-lethal doses of X-, fission neutron and beta irradiations. The effects appeared early and existed temporarily; their intensities and the restitution of membrane function depended on radiation doses, types and conditions of cells. In the present paper further aspects of structural and functional derangements of plasma membranes are introduced which were provoked by X- and tritium beta irradiation in the dose range up to 2.5 Gy and in the concentration range from 3.7 kBq/mL, respectively. The state of membrane structure was followed by bindings of various ligands of different receptor requirements, concanavalin A, cationized ferritin and polio virus. In the case of X-irradiation the binding conditions suggest the shift of overall negative surface charges to less negative ones. It was also found that radiation-induced phenomena appear on the cell surface unevenly. Long- and short-term treatments of cells with 3 H-thymidine and 3 H-water also perturb the plasma membrane; beta irradiation affects it directly. Membrane structure and function are suggested to offer good biological models to study correlation of energy deposition and biological effects, both restricted to domains of nanometre range. The data give evidence for radiation-induced membrane alterations in the sub-lethal or non-lethal ranges which might have consequences in the development of stochastic and non-stochastic effects. (author)

Inhibition of potential lethal damage repair and related gene expression after carbon-ion beam irradiation to human lung cancer grown in nude mice

International Nuclear Information System (INIS)

Yashiro, Tomoyasu; Fujisawa, Takehiko; Koyama-Saegusa, Kumiko; Imai, Takashi; Miyamoto, Tadaaki

2007-01-01

Using cultured and nude mouse tumor cells (IA) derived from a human lung cancer, we previously demonstrated their radiosensitivity by focusing attention on the dynamics of tumor clonogens and the early and rapid survival recovery (potential lethal damage repair: PLD repair) occurring after X-ray irradiation. To the authors' knowledge, this is the first study demonstrating gene expression in association with PLD repair after carbon-ion beam or X-ray irradiation to cancer cells. In this study we tried to detect the mechanism of DNA damage and repair of the clonogens after X-ray or carbon-ion beam irradiation. At first, colony assay method was performed after irradiation of 12 Gy of X-ray or 5 Gy of carbon-ion beam to compare the time dependent cell survival of the IA cells after each irradiation pass. Second, to search the genes causing PLD repair after irradiation of X-ray or carbon-ion beam, we evaluated gene expressions by using semi-quantitative RT-PCR with the selected 34 genes reportedly related to DNA repair. The intervals from the irradiation were 0, 6, 12 and 24 hr for colony assay method, and 0, 3, 18 hr for RT-PCR method. From the result of survival assays, significant PLD repair was not observed in carbon-ion beam as compared to X-ray irradiation. The results of RT-PCR were as follows. The gene showing significantly higher expressions after X-ray irradiation than after carbon-ion beam irradiation was PCNA. The genes showing significantly lower expressions after X-ray irradiation rather than after carbon-ion beam irradiation were RAD50, BRCA1, MRE11A, XRCC3, CHEK1, MLH1, CCNB1, CCNB2 and LIG4. We conclude that PCNA could be a likely candidate gene for PLD repair. (author)

In vitro gamma irradiation Medical Center of leukemic cells in mice, rats, and guinea pigs

International Nuclear Information System (INIS)

Gross, L.; Dreyfuss, Y.; Ehrenreich, T.; Feldman, D.; Limbert, L.M.

1980-01-01

In vitro gamma irradiation of virus-induced (Gross) mouse leukemia cells at doses of 350 to 1600 rads (1 rad = 0.01 gray) had no effect on their ability to induce leukemia, usually within 2 weeks, after transplantation into syngeneic mice. However, when cells irradiated at doses of 2000-20,000 rads were transplanted, they induced leukemia after a latency period exceeding 2.5 months, similar to the results observed in mice inoculated with filtered mouse leukemia extracts. Similar results were also obtained after irradiation of leukemic cells derived from rats in which leukemia had been induced by rat-adapted mouse leukemia virus. Apparently, gamma irradiation at a dose of, or exceeding, 2000 rads, inhibits the ability of mouse and rat leukemic cells to induce leukemia after transplantation into syngeneic hosts; however, it does not inactivate the virus carried by such cells nor prevent it from inducing leukemia. [In previous experiments, doses of more than 4,500,000 rads were needed to inactivate the passage A (Gross) leukemia virus carried in either mouse or rat leukemic cells.] In vitro gamma irradiation of L2C guinea pig leukemic cells at doses of 750 to 2500 rads had no apparent effect on their ability to induce leukemia after transplantation into strain 2 guinea pigs. However, irradiation at doses of 3250 to 20,000 rads inactivated their ability to do so. The morphology of mouse, rat, and guinea pig leukemic cells and the virus particles present in such cells was not affected by irradiation at doses of 20,000 rads

Free radical scavenging and the expression of potentially lethal damage in X-irradiated repair-deficient Escherichia coli

International Nuclear Information System (INIS)

Billen, D.

1987-01-01

When cells are exposed to ionizing radiation, they suffer lethal damage (LD), potentially lethal damage (PLD), and sublethal damage (SLD). All three forms of damage may be caused by direct or indirect radiation action or by the interaction of indirect radiation products with direct DNA damage. In this report I examine the expression of LD and PLD caused by the indirect action of X rays in isogenic, repair-deficient Escherichia coli. The radiosensitivity of a recA mutant, deficient both in pre- and post replication recombination repair and SOS induction (inducible error-prone repair), was compared to that of a recB mutant which is recombination deficient but SOS proficient and to a previously studied DNA polymerase 1-deficient mutant (polA) which lacks the excision repair pathway. Indirect damage by water radicals (primarily OH radicals) was circumvented by the presence of 2 M glycerol during irradiation. Indirect X-ray damage by water radicals accounts for at least 85% of the PLD found in exposed repair-deficient cells. The DNA polymerase 1-deficient mutant is most sensitive to indirect damage with the order of sensitivity polA1 greater than recB greater than or equal to recA greater than wild type. For the direct effects of X rays the order of sensitivity is recA greater than recB greater than polA1 greater than wild type. The significance of the various repair pathways in mitigating PLD by direct and indirect damage is discussed

Oxygen-dependent radiosensitivity of Escherichia coli and mitigation in lethality by superoxide dismutase

International Nuclear Information System (INIS)

Niwa, Taeko; Yamaguchi, Hikoyuki; Yano, Keiji

1978-01-01

Oxygen-dependent radiosensitivity of Escherichia coli W3623 his - was confirmed. Regarding cellular superoxide dismutase (SOD), cells grown oxically gained higher activity than those anoxically, however, the reinforced enzyme level could not compensate the oxygen effect, i.e., the enhanced lethal effect of oxic γ-irradiation. Rather, the enhancement of oxygen effect was found in cells grown oxically compared with those anoxically. Oxygen enhanced lethality was mitigated to the extent by the amount of added SOD into the cell suspension to be irradiated. The results supported a proposal that superoxide anion, O 2 - , is involved in the oxygen effect, with the most likely site of the damage in the outer structure of cell but not in the cell matrix. Reverse oxygen effect could be found with lambda phage DNA in transfecting ability. Added SOD protected phage DNA somewhat in oxic irradiation. While considerable protections were found in anoxic one with the added SOD even autoclaved but their function was still unknown. (auth.)

Modification of radiation-induced sex-linked recessive lethal mutation frequency by tocopherol

International Nuclear Information System (INIS)

Beckman, C.; Roy, R.M.; Sproule, A.

1982-01-01

The present study evaluates the effect of supplementing culture medium with α-tocopherol acetate on the yield of sex-linked recessive lethal mutants induced by X-irradiation in mature sperm of Drosophila. Although tocopherol treatment of males had no impact on the yield of mutations, a drastic reduction in mutation frequency was observed when irradiated males were mated to females raised and subsequently maintained on tocopherol-enriched diet. (orig./MG)

In vivo studies on the efficiency of irradiation with carbon ions at the syngeneic prostate carcinoma model R3327; In vivo Untersuchungen zur Wirksamkeit von Bestrahlungen mit Kohlenstoffionen am syngenen Prostatakarzinom Modell R3327

Energy Technology Data Exchange (ETDEWEB)

Glowa, Christin

2013-07-01

The aim of this study is to characterize differential effects after carbon ion ({sup 12}C) relative to photon irradiations in vivo in three different sublines of the syngeneic rat prostate adenocarcinoma (PCa) R3327 (AT1, HI, and H) as well as to identify tumor specific influence factors of the radiation response. Subcutaneous PCa tumor fragments in rats were irradiated with single (1 Fx) or split (2 Fx) doses of photons or carbon ions (75 keV/μ), respectively. Primary endpoint was local tumor control after 300 days. Based on dose-response curves, the TCD{sub 50{sup -}} values (dose at 50% tumor control probability) were used to calculate the relative biological effectiveness (RBE) of carbon ions. Additionally, potential carbon ion specific irradiation effects were studied. For this, in vivo tumor-physiological changes, structural and functional radiation- induced effects of gene expression as well as tumor subpopulations with tumor-inducing properties were investigated. For {sup 12}C- irradiations with 1 Fx or 2 Fx, the RBEs were 1.62 (H), 2.08 (HI) and 2.3 (AT1) and 1.9 (H), 2.1 (HI) and 2.67 (AT1), respectively. Isoeffective irradiation with photons and {sup 12}C- ions showed different kinetics of the radiation response. Magnetic resonance imaging (MRI) and histology showed a faster and stronger increase of tumor vessel permeability after {sup 12}C- irradiation compared to photons. After irradiation, DNA-repair mechanisms, immune system components and migration were induced, in contrast cell cycle progression, adhesion, angiogenesis, and the aerobic metabolism were downregulated. Especially, the kinetics of signaling cascades, apoptosis and stress-response were dependent on irradiation modality. In HI- and H-tumors CD24{sup +}/CD45{sup -} cells were identified as tumor inducing cells (TICs) in vivo. All three sublines were established under cell culture conditions to enable further molecular biological analyses. In conclusion, {sup 12}C- irradiation is

Analysis of recessive sex-linked lethal mutations in genetically different strains of Drosophila melanogaster ms and w irradiated in the five-kilometer zone of the Chernobyl meltdown

International Nuclear Information System (INIS)

Aslanyan, M.M.; Kim, A.I.; Magomedova, M.A.; Fatkulbayanova, N.L.

1994-01-01

The frequency of induced and spontaneous recessive sex-linked lethal mutations (RSLLM) in Drosophila melanogaster strains w and ms was estimated after their chronic irradiation in the five-kilometer zone of the Chernobyl' meltdown. The mutagenic effect of relatively low radiation doses was analyzed. In an experiment conducted in 1990, a significant increase in the RSLLM frequency was recorded, while, in 1991, no significant difference between the experiment and control was found

Chloroquine Improves Survival and Hematopoietic Recovery After Lethal Low-Dose-Rate Radiation

International Nuclear Information System (INIS)

Lim Yiting; Hedayati, Mohammad; Merchant, Akil A.; Zhang Yonggang; Yu, Hsiang-Hsuan M.; Kastan, Michael B.; Matsui, William; DeWeese, Theodore L.

2012-01-01

Purpose: We have previously shown that the antimalarial agent chloroquine can abrogate the lethal cellular effects of low-dose-rate (LDR) radiation in vitro, most likely by activating the ataxia-telangiectasia mutated (ATM) protein. Here, we demonstrate that chloroquine treatment also protects against lethal doses of LDR radiation in vivo. Methods and Materials: C57BL/6 mice were irradiated with a total of 12.8 Gy delivered at 9.4 cGy/hour. ATM null mice from the same background were used to determine the influence of ATM. Chloroquine was administered by two intraperitoneal injections of 59.4 μg per 17 g of body weight, 24 hours and 4 hours before irradiation. Bone marrow cells isolated from tibia, fibula, and vertebral bones were transplanted into lethally irradiated CD45 congenic recipient mice by retroorbital injection. Chimerism was assessed by flow cytometry. In vitro methylcellulose colony-forming assay of whole bone marrow cells and fluorescence activated cell sorting analysis of lineage depleted cells were used to assess the effect of chloroquine on progenitor cells. Results: Mice pretreated with chloroquine before radiation exhibited a significantly higher survival rate than did mice treated with radiation alone (80% vs. 31%, p = 0.0026). Chloroquine administration before radiation did not affect the survival of ATM null mice (p = 0.86). Chloroquine also had a significant effect on the early engraftment of bone marrow cells from the irradiated donor mice 6 weeks after transplantation (4.2% vs. 0.4%, p = 0.015). Conclusion: Chloroquine administration before radiation had a significant effect on the survival of normal but not ATM null mice, strongly suggesting that the in vivo effect, like the in vitro effect, is also ATM dependent. Chloroquine improved the early engraftment of bone marrow cells from LDR-irradiated mice, presumably by protecting the progenitor cells from radiation injury. Chloroquine thus could serve as a very useful drug for protection

Reproductive and genetic effects of continuous prenatal irradiation in the pig

International Nuclear Information System (INIS)

Erickson, B.H.; Martin, P.G.

1984-01-01

The stem germ cells of the prenatal pig are highly vulnerable to the cytotoxic effects of ionizing irradiation. This study was conducted to determine whether sensitivity to killing was also marked by a sensitivity to mutation and how prenatal depletion of the germ-cell population affects reproductive performance. Germ-cell populations were reduced by continuously irradiating sows at dose rates of either 0.25 or 1.0 rad/day for the first 108 days of gestation. The prenatally irradiated boars were tested for sperm-producing ability, sperm abnormalities, dominant lethality, reciprocal translocations, and fertility. Prenatally irradiated females were allowed to bear and nurture one litter, then tested for dominant lethality in a second litter; germ cell survival and follicular development were assessed in their serially sectioned ovaries. Sperm production was not significantly affected in the 0.25-rad boars, but boars irradiated with 1.0 rad per day produced sperm at only 17% of the control level. Incidence of defective sperm was 4.9% and 11.1% in the 0.25 and 1.0 groups, respectively. Four of the 1.0-rad boars were infertile, but prenatal irradiation apparently caused neither dominant lethality nor reciprocal translocations in fertile males. Number of oocytes was reduced to 66 +/- 7% of control in the 0.25-rad gilts, but reproductive performance was unaffected and no dominant lethality was observed. Only 7 +/- 1% of the oocytes survived in the 1.0-rad group. Reproductive performance was normal for the first litter, but four of the 23 sows tested were infertile at the second litter and a significant incidence of dominant lethality was observed

Action of caffeine on x-irradiated HeLa cells. VII. Evidence that caffeine enhances expression of potentially lethal radiation damage

International Nuclear Information System (INIS)

Beetham, K.L.; Tolmach, L.J.

1984-01-01

HeLa cells irradiated with 2 Gy of 220-kV X rays suffer a 60-70% loss of colony-forming ability which is increased to 90% by postirradiation treatment with 10 mM caffeine for 6 hr. The detailed postirradiation patterns of cell death and sister-cell fusion in such cultures and in cultures in which the colony-forming ability was brought to about the same level by treatment with a larger (4 Gy) X-ray dose alone or by longer (48 hr) treatment with 10 mM caffeine alone were recorded by time-lapse cinemicrography. Because the patterns of cell death and fusion differ radically in irradiated and in caffeine-treated cultures, the response of the additional cells killed by the combined treatment can be identified as X-ray induced rather than caffeine induced. The appearance of cultures after several days of incubation confirms the similarity of the post-treatment patterns of proliferation in cultures suffering enhanced killing to those occurring in cultures treated with larger doses of X rays alone. It is concluded that x rays do not sensitize cells to caffeine, but rather that caffeine enhanced the expression of potentially lethal radiation-induced damage

National food irradiation programme of Japan

International Nuclear Information System (INIS)

Fujimaki, M.

1982-01-01

The present state of studies on feasibility and wholesomeness of irradiated food is presented. Irradiation projects were realized of potatoes, onions, wheat, Vienna sausages, fish-paste products, and mandarine oranges. Mutagenecity tests with Salmonella or E. coli, chromosome aberration tests, dominant lethal tests, fibroblasts and micronucleus tests, and toxicity tests performed in amimals fed with irradiated food showed no positive results

Fate of bone marrow stromal cells in a syngenic model of bone formation.

Science.gov (United States)

Boukhechba, Florian; Balaguer, Thierry; Bouvet-Gerbettaz, Sébastien; Michiels, Jean-François; Bouler, Jean-Michel; Carle, Georges F; Scimeca, Jean-Claude; Rochet, Nathalie

2011-09-01

Bone marrow stromal cells (BMSCs) have been demonstrated to induce bone formation when associated to osteoconductive biomaterials and implanted in vivo. Nevertheless, their role in bone reconstruction is not fully understood and rare studies have been conducted to follow their destiny after implantation in syngenic models. The aim of the present work was to use sensitive and quantitative methods to track donor and recipient cells after implantation of BMSCs in a syngenic model of ectopic bone formation. Using polymerase chain reaction (PCR) amplification of the Sex determining Region Y (Sry) gene and in situ hybridization of the Y chromosome in parallel to histological analysis, we have quantified within the implants the survival of the donor cells and the colonization by the recipient cells. The putative migration of the BMSCs in peripheral organs was also analyzed. We show here that grafted cells do not survive more than 3 weeks after implantation and might migrate in peripheral lymphoid organs. These cells are responsible for the attraction of host cells within the implants, leading to the centripetal colonization of the biomaterial by new bone.

Quantitative aspects of repair of potentially lethal damage in mammalian cells

International Nuclear Information System (INIS)

Iliakis, G.; Pohlit, W.

1979-01-01

Stationary cultures of Ehrlich ascites tumour cells were irradiated with X-rays and then immediately or after a time interval tsub(rep) plated to measure the survival. The increase in survival observed after delayed plating was interpreted as repair of potentially lethal damage. A cybernetic model was used to analyse these data. Three states of damage were assumed for the cells. In state A the cells could grow to macrocolonies, in state B the cells suffered potentially lethal damage and could grow to macrocolonies only if they were allowed to repair the damage and in state C the cells were lethally damaged. A method of deriving the values of the parameters of the model from the experimental data was given. The dependence of the reaction rate constant of the repair potentially lethal damage on the dose D was used to derive a possible mechanism for the production of the shoulder in the dose effect curve. Finally this model was compared with other models of radiation action in living cells. (author)

The lethal interaction of x ray and penicillin induced lesions following x-irradiation of Escherichia coli B/r in the presence of hypoxic cell sensitizers

International Nuclear Information System (INIS)

Gillies, N.E.; Obioha, F.I.

1982-01-01

When Escherichia coli B/r were x-irradiated under anoxia in the presence of different electron-affinic sensitizers and then incubated in broth containing penicillin (at a concentration that did not kill unirradiated cells) additional killing of the bacteria occurred provided the sensitizers were of relatively high lipophilicity. The overall effect was to increase the efficiency of these sensitizers. It is concluded that sensitizer-dependent latent radiation lesions(s) are produced in membrane components of the cell envelope that interact with damage caused by penicillin in the peptidoglycan layer and this causes the additional lethality

Molecular basis of the mutagenic and lethal effects of ultraviolet irradiation

International Nuclear Information System (INIS)

Grossman, L.

1982-01-01

Using bacteria as a model, the molecular basis of the mutagenic and lethal effects of uv radiation is being studied. Attention is focused on the mechanism of action of uv-1 specific endonucleases in the repair of damaged DNA. The isolation and identification of similar enzymes in human cells are being conducted concurrently

Alkali-labile sites and post-irradiation effects in single-stranded DNA induced by H radicals

International Nuclear Information System (INIS)

Lafleur, M.V.M.; Heuvel, N. van; Woldhuis, J.; Loman, H.

1978-01-01

Single-stranded phiX174 DNA in aqueous solutions has been irradiated in the absence of oxygen, under conditions in which H radicals react with the DNA. It was shown that H radical reactions result in breaks, which contribute approximately 10 per cent inactivation. Further, two types of alkali-labile sites were formed. One was lethal and gave rise to single-strand breaks by alkali and was most probably identical with post-irradiation heat damage and contributed about 33 per cent to the inactivation mentioned above. The other consisted of non-lethal damage, partly dihydropyrimidine derivatives, and was converted to lethal damage by alkali. This followed from experiments in which the DNA was treated with osmium-tetroxide, which oxidized thymine to 5,6-dihydroxydihydrothymine. Treatment with alkali of this DNA gave the same temperature dependence as found for the non-lethal alkali-labile sites in irradiated DNA. A similar temperature dependence was found for dihydrothymine and irradiated pyrimidines with alkali. (author)

The effect of 60Co γ-rays irradiation on seeds and branches of Euonymus fortunei

International Nuclear Information System (INIS)

Ao Yan; Inner Mongolia Agriculture Univ., Huhhot; Zhang Guosheng; Lu Renqiang; Pan Qinghua

2006-01-01

Seeds and plant branches of Euonymus fortunei were irradiated with 60 Co γ-ray. The results showed that after irradiation, seed germination rate, emergence rate and surviving rate were restrained, and it was negatively correlated with irradiation dose increasing significantly. The first euphylis period was delayed compared with control. Seedling height decreased with the increase of irradiation dose. Semi-lethal dose of Euonymus fortunei seeds was 128.56 Gy. Branch irradiation could cause significantly number and length reduced, and it is correlated with irradiation dose increasing. The semi-lethal dose for Euonymus fortunei branches was 95.54 Gy. (authors)

Relative effect of radiation dose rate on hemopoietic and nonhemopoietic lethality of total-body irradiation

International Nuclear Information System (INIS)

Peters, L.J.; McNeill, J.; Karolis, C.; Thames, H.D. Jr.; Travis, E.L.

1986-01-01

Experiments were undertaken to determine the influence of dose rate on the toxicity of total-body irrdiation (TBI) with and without syngeneic bone-marrow rescue in mice. The results showed a much greater dose-rate dependence for death from nonhemopoietic toxicity than from bone-marrow ablation, with the ratio of LD 50 's increasing from 1.73 at 25 cGy/min to 2.80 at 1 cGy/min. At the higher dose rates, dose-limiting nonhemopoietic toxicity resulted from late organ injury, affecting the lungs, kidneys, and liver. At 1 cGy/min the major dose-limiting nonhemopoietic toxicity was acute gastrointestinal injury. The implications of these results in the context of TBI in preparation for bone-marrow transplantation are discussed. 15 refs., 4 figs

Estimation of mutation rates induced by large doses of gamma, proton and neutron irradiation of the X-chromosome of the nematode Panagrellus redivivus

International Nuclear Information System (INIS)

Denich, K.T.R.; Samoiloff, M.R.

1984-01-01

The radiation-resistant free-living nematode Panagrellus redivivus was used to study mutation rates in oocytes, following gamma, proton and neutron irradiation in the dose range 45-225 grays. γ-Radiation produced approximately 0.001 lethal X-chromosomes per gray over the range tested. Proton or neutron irradiation produced approximately 0.003 lethal X-chromosomes per gray at lower doses, with the mutation rate dropping to 0.001 lethal X-chromosome per gray at the higher doses. These results suggest a dose-dependent mutation-repair system. Cell lethality was also examined. γ-Radiation produced the greatest amount of cell lethality at all doses, while neutron irradiation had no cell lethal effect at any of the doses examined. (orig.)

Feeding Studies of Irradiated Foods with Insects

Energy Technology Data Exchange (ETDEWEB)

Loaharanu, Srisan

1978-06-15

Insects are of value to man in many scientific studies. Microsomal detoxication systems exist in both insects and mammals. In the preliminary investigations it was found that irradiated cocoa beans and white and red kidney beans (Phaseolus spp.) did not significantly change the percentage of egg-hatch in the insects tested. In more detailed investigations food samples that are susceptible to insect spoilage and are representatives of widely consumed human foods were fed to various insect species. The development, sex distortion and reproductivity of the insects were investigated. Cytogenetic aberrations as related to dominant lethality were studied in insects with reasonably clear chromosomal patterns. The meiosis stage was examined, using the squash technique and Aceto-orcein staining. Black beans, Phaseolus spp., irradiated with up to 200 krad of gamma rays did not apparently change the percentage of survival and the sex ratio of the bean weevil, Zabrotes subfasciatus. Dominant lethality in the German cockroach, Blatella germanica, fed on irradiated black beans did not apparently occur when considering the results of cytological investigation and the number of offspring obtained. Dried sardine samples irradiated with up to 400 krad of gamma rays neither apparently affected the survival nor caused sex distortion in the cheese skipper, Piophila casei. This irradiated product apparently did not induce dominant lethality in the German cockroach as tested. Coffee processed from coffee beans that had been irradiated with up to 100 krad of gamma rays did not apparently cause adverse effects on the experimental insects. (author)

Feeding studies of irradiated foods with insects

International Nuclear Information System (INIS)

Loaharanu, S.

1978-01-01

Insects are of value to man in many scientific studies. Microsomal detoxication systems exist in both insects and mammals. In the preliminary investigations it was found that irradiated cocoa beans and white and red kidney beans (Phaseolus spp.) did not significantly change the percentage of egg-hatch in the insects tested. In more detailed investigations food samples that are susceptible to insect spoilage and are representatives of widely consumed human foods were fed to various insect species. The development, sex distortion and reproductivity of the insects were investigated. Cytogenetic aberrations as related to dominant lethality were studied in insects with reasonably clear chromosomal patterns. The meiosis stage was examined, using the squash technique and Aceto-orcein staining. Black beans, Phaseolus spp., irradiated with up to 200 krad of gamma rays did not apparently change the percentage of survival and the sex ratio of the bean weevil, Zabrotes subfasciatus. Dominant lethality in the German cockroach, Blatella germanica, fed on irradiated black beans did not apparently occur when considering the results of cytological investigation and the number of offspring obtained. Dried sardine samples irradiated with up to 400 krad of gamma rays neither apparently affected the survival nor caused sex distortion in the cheese skipper, Piophila casei. This irradiated product apparently did not induce dominant lethality in the German cockroach as tested. Coffee processed from coffee beans that had been irradiated with up to 100 krad of gamma rays did not apparently cause adverse effects on the experimental insects. (author)

Changes in some blood lipid fractions in whole-body irradiated rats as influenced by some radioprotectors

International Nuclear Information System (INIS)

Yousri, R.M.; Roushdy, H.; Gawish, M.A.M.

1991-01-01

The effect of sublethal and lethal total body gamma irradiation on some serum lipid fractions in male rats was investigated. The protective efficacy of estradiol and/or α-tocopherol was also studied. The results of this study demonstrate that the lethally irradiated rats showed significant alteration in serum triglycerides, cholesterol, total lipids and phospholipids level. Estradiol exerted a benefical effect on lipid fractions after one and two days post lethal α-irradiation (8 Gy). No consistent radioprotective effect of tocopherol could be detected on the levels of serum lipid fractions. This finding was also observed when both radioprotectors were used. (orig.) [de

Activation of specific cellular immunity toward murine leukemia in mice rejecting syngeneic somatic hybrid cells

International Nuclear Information System (INIS)

Liang, W.; Cohen, E.P.

1977-01-01

ASL-1 x LM(TK) - somatic hybrid cells form both H-2/sup a/ and H-2/sup k/ antigen complexes. After forming a localized tumor in syngeneic (A/J x C 3 H/HeJ)F 1 mice, they are rejected. Such mice are resistant to otherwise invariably lethal injections of ASL-1 cells, surviving for prolonged and, in some instances, indefinite periods. To examine the basis of immunity, the capacity of spleen cells from mice rejecting hybrid cells to stimulate the release of 51 Cr from labeled ASL-1 cells was investigated. Cells from the spleens of mice rejecting ASL-1 x LM(TK) - cells stimulated the release of 51 Cr from labeled ASL-1 cells, but not from Ehrlich ascites or P815 cells. Cells from mice injected with mitomycin-C-treated ASL-1 cells led to the release of 51 Cr from labeled ASL-1 cells as well, but the extent of 51 Cr release was approximately one-third as occurred in the presence of cells from hybrid cell-injected mice. Cells from noninjected mice or from mice injected with LM(TK) - cells failed to lead to the specific release of 51 Cr from ASL-1 cells. The presence of unlabeled ASL-1 cells, but not Ehrlich ascites cells, competitively inhibited the spleen cell-stimulated release of 51 Cr from labeled ASL-1 cells. Sera from A/J mice injected with mitomycin-C-treated ASL-1 cells contained antibodies specific for the tumor-associated antigen of ASL-1 cells

Seed irradiation with continuously increasing doses of thermal neutrons

International Nuclear Information System (INIS)

Uhlik, J.; Pfeifer, M.; Pittermann, P.

1977-01-01

In the 'Raman' pea cv. the biological activity of thermal neutrons was investigated after irradiation of a 780 mm column of seeds for 3000 and 4167 seconds with a flux of 5.607 x 10 9 n.cm -2 per second. For different fractions of the seed column the average density of the neutron flux was calculated. It was proved that for the described method of seed irradiation it was sufficient to determine only the dose approaching the lethal dose. If a sufficiently high column of seeds is used part of the column of seeds will be irradiated with the optimum range of doses. The advantages of the suggested method of irradiation are not only smaller time and technological requirements resulting from the need for the determination of only the critical lethal dose of radiation by means of inhibition tests performed with seedlings, but also a simpler irradiation procedure. The suggested method of irradiation is at least nine times cheaper. (author)

Hemopoiesis in bone marrow of lethally irradiated mice

International Nuclear Information System (INIS)

Viktora, L.; Zoubkova, M.; Urbankova, J.

1976-01-01

A percentual representation of individual types of cells and their share of the restoration of hemopoiesis in bone marrow was observed on the 9th, 12th, 16th and 20th days following transplantation of bone marrow cells to letally irradiated mice. Myelopoiesis was ascertained which on the 20th day after transplantation became the dominant constituent and reached peak level around the 16th day after transplantation. The examination further showed that with regard to the period of irradiation and transplantation the erythropoiesis in bone marrow culminates on the 9th day after the transplantation and that normal values are quickly restored. On the 2ath day myelopoiesis and lymphopoiesis come close to values in normal bone marrow

Dominant lethal effect of gamma radiation of 60Co in Biomphalaria glabrata (SAY, 1818)

International Nuclear Information System (INIS)

Tallarico, Lenita de Freitas

2003-01-01

Germ cell mutations are used in ecotoxicological studies as biomarkers of population effects and indicators of ecological changes. Biomphalaria glabrata, a freshwater mollusk, is a good experimental model for biomonitoring studies due to its biological characteristics and the ecological importance of this invertebrate group. The dominant lethal test was established in B. glabrata for the detection of germ cell mutations. Results with chemical mutagens showed that this system is efficient, specific and sensitive in the evaluation of germ cell mutations induced by reference mutagens. In this work, the dominant lethal effects of gamma radiation of 60 Co were studied. A preliminary experiment was done to establish the dose range and to estimate the chronology of spermatogenesis in B. glabrata. This estimate is possible because of the uniformity in response to ionizing radiation between germ cells at homologous stages of spermatogenesis in widely different species. In general, pre-meiotic germ cells are less sensitive to the induction of lethal dominant mutations than post-meiotic cells. This effect can be attributed to: young gametogenic cells - mitotically active - have greater repair ability from sub-lethal DNA damage and there is a selective elimination of the damaged cells. In our system: induction of lethal dominant mutations causes an increase in the frequency of malformations and, cytotoxic effect is displayed as a reduction in the crossing rates. Total duration of spermatogenesis was estimated in approximately 36 days, with the following distribution of stages: 1 to 13 days - spermatogonia, 14 to 20 days - spermatocytes, 21 to 36 days - spermatids and spermatozoa. Based on this chronology, irradiated wild-type snails with 2,5; 10 and 20Gy and crossed with non-irradiated albino snails after 7, 17, 23, 30 and 36 days. The frequencies of malformations in the heterozygous wild-type offspring of the nonirradiated albino snails were used as indicator of germ cell

Some mechanisms of disturbances and recovery of T-lymphocyte migratory properties in irradiated mice

International Nuclear Information System (INIS)

Anokhin, G.N.; Yarilin, A.A.

1984-01-01

Migration of 51 Cr-labelled T cells from irradiated mice into lymph nodes of syngeneic unirradiated recipients decreased in a dose-dependent fashion. Influx of labelled T cells between 4 and 24 hr after injection (secondary migration) is more radiosensitive than lymph-node migration of T cells in the first 4 hr (primary migration). Treatment of T cells from irradiated mice in vitro with Con A or with trypsin does not enhance radiation-induced alteration of their migratory properties, but irradiation enhances the effects of Con A and trypsin on T-cell migration. Recovery of primary migration of irradiated T cells is completed 3 months after irradiation; it is probably caused by T-cell renewal. The defect of T-cell secondary migration is more stable: it remains 6 months after irradiation in a dose of 4 gy. Post-irradiation defects of the T-cell differentiation process as a cause of long-lasting alteration of T-cell secondary migration are discussed. (author)

Evidence for mouse Th1- and Th2-like helper T cells in vivo. Selective reduction of Th1-like cells after total lymphoid irradiation

International Nuclear Information System (INIS)

Bass, H.; Mosmann, T.; Strober, S.

1989-01-01

Purified CD4+ BALB/c spleen T cells obtained 4-6 wk after total lymphoid irradiation (TLI) helped normal syngeneic B cells to produce a vigorous antibody response to TNP keyhole limpet hemocyanin in adoptive cell transfer experiments. However, the same cells failed to transfer delayed-type hypersensitivity to the adoptive hosts as measured by a foot pad swelling assay. In addition, purified CD4+ cells from TLI-treated mice were unable to induce graft vs. host disease in lethally irradiated allogeneic C57BL/Ka recipient mice. In response to mitogen stimulation, unfractionated spleen cells obtained from TLI mice secreted normal levels of IL-4 and IL-5, but markedly reduced levels of IL-2 and INF-gamma. A total of 229 CD4+ clones from spleen cells of both normal and TLI-treated mice were established, and the cytokine secretion pattern from each clone was analyzed. The results demonstrate that the ratio of Th1- and Th2-like clones in the spleens of normal BALB/c mice is 1:0.6, whereas the ratio in TLI mice is approximately 1:7. These results suggest that Th2-like cells recover rapidly (at approximately 4-6 wk) after TLI treatment and account for the early return of antibody helper activity and secretion of IL-4 and IL-5, but Th1-like cells recover more slowly (in approximately 3 mo) after irradiation, and this accounts for the deficit in cell-mediated immunity and the reduced amount of IL-2 and IFN-gamma secretion

Relationship of DNA repair and chromosome aberrations to potentially lethal damage repair in X-irradiated mammalian cells

International Nuclear Information System (INIS)

Fornace, A.J. Jr.; Nagasawa, H.; Little, J.B.

1980-01-01

By the alkaline elution technique, the repair of x-ray-induced DNA single strand breaks and DNA-protein cross-links was investigated in stationary phase, contact-inhibited mouse cells. During the first hour of repair, approximately 90% of x-ray induced single strand breaks were rejoined whereas most of the remaining breaks were rejoined more slowly during the next 5 h. The number of residual non-rejoined single strand breaks was approximately proportional to the x-ray dose at early repair times. DNA-protein cross-links were removed at a slower rate - T 1/2 approximately 10 to 12 h. Cells were subcultured at low density at various times after irradiation and scored for colony survival, and chromosome aberrations in the first mitosis after sub-culture. Both cell lethality and the frequency of chromosome aberrations decreased during the first several hours of repair, reaching a minimum level by 6 h; this decrease correlated temporally with the repair of the slowly rejoining DNA strand breaks. The possible relationship of DNA repair to changes in survival and chromosome aberrations is discussed

The clinic and pathologic picture in the lethal dose irradiated ewes

International Nuclear Information System (INIS)

Halagan, J.; Stanikova, A.; Maracek, I.

2004-01-01

The history of clinical symptoms as well as pathologic histological and morphological changes after long/lasting gamma irradiation were estimated in seven clinical healthy ewes. The animals were irradiated continually seven days with totally 6.7 Gy per ewe. Clinically recognizable symptoms of the radiation sickness were observed commencing the 4 th after last dose of irradiation. Sharp increase of the body temperature, heart and respiratory frequency rate as well as apathy, anorexia, arrhythmia, dyspnoe, diarrhea, dehydration, polyuria were prevalent in clinical founding . All of the animals were death in course of seven days after last irradiated dose. The gastrointestinal radiation syndrome was typical evidence of gastrointestinal tract and the general hemorrhagic enhancing of the gamma irradiation damage effects was confirmed. (authors)

Radiation-induced mutagenicity and lethality in Salmonella typhimurium

International Nuclear Information System (INIS)

Isildar, M.; Bakale, G.

1983-01-01

The mutagenic and lethal effects of ionizing radiation on histidine-deficient auxotrophs of Salmonella typhimurium were studied to improve the understanding of radiation damage to DNA. The auxotrophs were divided into two groups - one which is sensitive to base-pair substitutions and another sensitive to frameshifts. These groups were composed of parent-daughter pairs in which the chemical mutagenicity enhancing plasmid, pKM101, is absent in the parent strain and present in the daughter. Co-60 #betta#-radiation and 250 kV x-rays were used to irradiate the bacteria. Irradiation of the frameshift - sensitive strains which carry the pKm101 plasmid doubled the absolute number of induced revertants whereas irradiation of the base-pair substitution sensitive strain which also carries the pKm101 plasmid produced nearly no change in the number of induced revertants. A nearly negligible effect on the mutation rate was observed for all parent strains

Graft irradiation abrogates graft-versus-host disease in combined pancreas-spleen transplantation

International Nuclear Information System (INIS)

Schulak, J.A.; Sharp, W.J.

1986-01-01

A model of combined pancreas-spleen transplantation (PST) was studied in LBN F1 recipients of Lewis grafts in order to evaluate the efficacy of pretransplant graft irradiation in preventing lethal graft-versus-host disease (GVHD). Recipients of unmodified PST uniformly developed severe GVHD and died (MST = 16.7 +/- 3.8 days). Whole body donor irradiation with either 500 or 250 rad prevented lethal GVHD. Similarly, ex vivo graft irradiation with either 1000 or 500 rad also resulted in normal weight gain, graft function, and host survival for the 6-week study period. Conversely, delay of graft irradiation until 3 days after transplantation failed to prevent this complication (MST = 15.8 +/- 3.7 days). Recipients of irradiated grafts displayed glucose tolerance tests that were identical to those in the control group indicating that the doses of radiation employed in these experiments were not deleterious to islet function. Irradiated spleen grafts appeared histologically normal at 6 weeks after transplantation. Cells derived from these grafts failed to stimulate lymph node enlargement in a popliteal lymph node assay for GVHD, suggesting that these spleens may have become repopulated with host cells. These experiments confirm that PST has the potential to cause lethal GVHD and suggest that pretransplant graft irradiation may be used to prevent its occurrence

Effect of selective T cell depletion of host and/or donor bone marrow on lymphopoietic repopulation, tolerance, and graft-vs-host disease in mixed allogeneic chimeras (B10 + B10.D2----B10)

International Nuclear Information System (INIS)

Ildstad, S.T.; Wren, S.M.; Bluestone, J.A.; Barbieri, S.A.; Stephany, D.; Sachs, D.H.

1986-01-01

Reconstitution of lethally irradiated mice with a mixture of T cell-depleted syngeneic plus T cell-depleted allogeneic bone marrow (B10 + B10.D2----B10) leads to the induction of mixed lymphopoietic chimerism, excellent survivals, specific in vivo transplantation tolerance to subsequent donor strain skin grafts, and specific in vitro unresponsiveness to allogeneic donor lymphoid elements as assessed by mixed lymphocyte reaction (MLR) proliferative and cell-mediated lympholysis (CML) cytotoxicity assays. When B10 recipient mice received mixed marrow inocula in which the syngeneic component had not been T cell depleted, whether or not the allogeneic donor marrow was treated, they repopulated exclusively with host-type cells, promptly rejected donor-type skin allografts, and were reactive in vitro to the allogeneic donor by CML and MLR assays. In contrast, T cell depletion of the syngeneic component of the mixed marrow inocula resulted in specific acceptance of allogeneic donor strain skin grafts. Such animals were specifically unreactive to allogeneic donor lymphoid elements in vitro by CML and MLR, but were reactive to third party. When both the syngeneic and allogeneic marrow were T cell depleted, variable percentages of host- and donor-type lymphoid elements were detected in the mixed reconstituted host. When only the syngeneic bone marrow was T cell depleted, animals repopulated exclusively with donor-type cells. Although these animals had detectable in vitro anti-host (B10) reactivity by CML and MLR and reconstituted as fully allogeneic chimeras, they exhibited excellent survival and had no in vivo evidence for graft-vs-host disease. Experiments in which untreated donor spleen cells were added to the inocula in this last group suggest that the presence of T cell-depleted syngeneic bone marrow cells diminishes graft-vs-host disease and the mortality from it

Differential effect of procaine on irradiated mammalian cells in culture

International Nuclear Information System (INIS)

Djordjevic, B.

1979-01-01

HeLa and V-79 Chinese hamster cells temporarily stored in ampoules were treated with the local anesthetic procaine. Postirradiation treatment increased lethality in HeLa cells depending on drug concentration, duration of treatment, and cell density, as measured by colony-forming ability upon plating. If present during irradiation only, procaine protected from irradiation. In V-79 cells, procaine potentiated radiation lethality only in freshly trypsinized cells. Procaine effect was thus cell type specific and most likely involved the cell membrane

Allosuppressor and allohelper T cells in acute and chronic graft-vs-host disease. I. Alloreactive suppressor cells rather than killer T cells appear to be the decisive effector cells in lethal graft-vs.-host disease

NARCIS (Netherlands)

Rolink, A. G.; Radaszkiewicz, T.; Pals, S. T.; van der Meer, W. G.; Gleichmann, E.

1982-01-01

Splenic T cells from B10 donors were injected into irradiated (B10 x DBA/2)F1 mice. Either 5 or 6 d later, activated donor T cells were recovered from the spleens of these primary F1 (1 degree F1) recipients and transferred to groups of nonirradiated syngeneic F1 (2 degrees F1) recipients. Whereas

Both caffeine-induced lethality and the negative liquid holding effect, in UV- or γ-irradiated wild-type Schizosaccharomyces pombe, are consequences of interference with a recombinational repair process

International Nuclear Information System (INIS)

Gentner, N.E.

1981-01-01

UV-or γ-irradiated G2 phase cells of rad + Schizosac charonmyces pombe show increased inactivation if incubated postirradiation, in liquid growth medium containing caffeine, before being plated on normal agar medium. The following however, do not show such caffeine-induced lethality: G1 phase rad + cells; ascospores of a rad + strain; either G2 or G1 phase cells of the recombination-deficient rad1 strain; unirradiated rad + cells. Of the above, only the G2 phase rad + cells possess, at the time of radiation exposure, the capability for recombination. Similarly, the negative liquid holding effect is manifested only in G2 phase rad + cells. Both the negative liquid holding effect and caffeine-induced lethality therefore are seen only in cells which fulfill all of the following conditions: (a) they must be genetically recombination-proficient; (b) they must possess at the time of irradiation the necessary two DNA copies with which to perform recombinational repair (for a haploid cell, this means they must be in G2 phase); (c) their DNA must be damaged, such as by UV or γ-ray exposure, thus requiring that recombinational repair capability be exercised in order to maintain viability; and (d) they must be incubated under conditions that fail to support the normal progress of recombinational repair. (orig./AJ) [de

Dominant lethal mutations and histological changes produced in mouse oocytes by gamma irradiation

International Nuclear Information System (INIS)

Vyglenov, A.; Baev, I.; Rupova, I.; Kusheva, R.

1976-01-01

Mouse female were exposed to a total dose of 500 or 1000 rad 137 Cs gamma rays delivered at 0.01 rad/min. Effects were scored at 1, 5, 7, and 10 weeks after cessation of treatment. Histologically, ovaria in the 500 rad group showed a decrease up to 11% in follicle numbers as compared to controls; with the prolongation of the time after exposure, a further fall in follicle numbers is observed. In the 1000 rad group, depopulation of ovaria was complete. With the 500 rad dose, total dominant lethality was found to be increased for any of the time intervals between radiation exposure and conception; postimplantation dominant lethality was comparatively low, with similar scores between the weeks investigated. (author)

Significance of bacterial flora in abdominal irradiation-induced inhibition of lung metastases

International Nuclear Information System (INIS)

Matsumoto, T.; Ando, K.; Koike, S.

1988-01-01

We have previously reported that abdominal irradiation prior to i.v. injection of syngeneic tumor cells reduced metastases in lung. Our report described an investigation of the significance of intestinal organisms in the radiation effect. We found that eliminating intestinal organisms with antibiotics totally abolished the radiation effect. Monoassociation of germ-free mice revealed that the radiation effect was observable only for Enterobacter cloacae, never for Streptococcus faecium, Bifidobacterium adlesentis, or Escherichia coli. After abdominal irradiation of regular mice, E. cloacae multiplied in cecal contents, adhered to mucous membranes, invaded the cecal wall, and translocated to mesenteric lymph nodes. Intravenous administration of E. cloacae in place of abdominal irradiation inhibited metastases. E. cloacae-monoassociated mice developed fewer metastases than germ-free mice, and the reduction was further enhanced by abdominal irradiation. We concluded that abdominal irradiation caused the invasion of E. cloacae from the mucous membrane of the intestine and inhibited formation of lung metastases

The role of cell progression in potentiation of radiation lethality by hyperthermia and by chemical means

International Nuclear Information System (INIS)

Djordjevic, B.; Lange, C.S.

1984-01-01

Aerobic stationary dense cultures of HeLa cells show very little potentiation of radiation lethality when irradiated cells are incubated with procaine HCl for two hours at 37 0 C, but if cells are diluted in fresh medium after irradiation and incubated for two hours with procaine, a high degree of radiopotentiation is obtained. This effect is not cell density dependent, since the addition of heavily irradiated cells to achieve comparable densities did not diminish lethality in the diluted culture. Procaine radiopotentiation at 37 0 C could be prevented by simultaneous administration with procaine of the protein synthesis inhibitor cycloheximide. Since cycloheximide inhibits cell cycle progression (with block points in G1 and G2) progression is strongly implicated in the phenomenon of radiopotentiation. Cell progression may be also involved in hyperthermic radiopotentiation: adding cycloheximide during heating of irradiated cells at 41 0 C for two hours increased survival. This effect of cycloheximide is even more pronounced in cells also treated with procaine during heating, thus diminishing the interaction of heat and procaine in radiopotentiation. Data pertaining to cell progression in synchronous cultures of HeLa cells under various treatment conditions are presented and discussed

Effect of lethal and sub-lethal concentrations of tobacco (Nicotiana ...

African Journals Online (AJOL)

Lethal and sub-lethal bioassays on Clarias gariepinus were conducted to evaluate the toxicity of tobacco (Nicotiana tobaccum) leaf dust on weight gain and haematological indices of Clarias gariepinus (mean weight 10.5±0.70g) in glass aquaria with aeration system. The concentrations used during the lethal exposure are: ...

Preliminary report on the sensitivity of tea plant to irradiation

International Nuclear Information System (INIS)

Dong Lijuan

1985-01-01

The seeds of different varieties of tea have been irradiated. In most cases the rate of emergence of seedings was delayed and the rate of emergence of seedlings was decreased with increasing the radiation doses. The more suitable doses for tea seeds were 5 Krads, and the lethal dose is over 7 Krads. Except for the variety Fudingdabai, the survival rate of cuttings was decreased and its growth rate was reduced with increasing the radiation doses. The applicable dose and the lethal dose for cuttings were 0.5-1 Krads and 2 Krads respectively. Irradiation with low dose (below 4 Krads) give a good effect in the germination of pollen. The semilethal dose for pollen is 12 Krads, and the lethal dose is more than 20 Krads

Enhancement of syngeneic murine tumour transplantability by whole body irradiation

International Nuclear Information System (INIS)

Peters, L.J.

1975-01-01

Experiments were undertaken to test the general validity of the assumption that potentiation of tumour transplantability by sublethal whole body irradiation (WBI) implies some degree of immunological resistance in the intact host. A transplantable carcinoma of spontaneous origin in CBA mice which exhibits a large WBI effect was assayed quantitatively in mice which had been immunologically crippled in terms of allograft acceptance by depletion of thymus derived lymphocytes. The mean number of tumour cells required for 50% successful takes (TD 50 ) in these mice was found to be not significantly different from that in normal controls but highly significantly greater than in WBI mice. On the other hand, in mice which underwent laparotomy immediately before assay, the TD 50 was reduced significantly though not to the same extent as in WBI mice. It was concluded that WBI effect was not due to impaired host immunity but possibly to physiological changes resulting from acute stress. The hypothesis that hyperfibrinogenaemia which occurs after both WBI and laparotomy might increase tumour transplantability was rejected because of the lack of correlation between TD 50 and fibrinogen levels at different times after each procedure. From this and other work it is apparent that TD 50 data, in themselves, give no reliable indication of host immunity. (author)

Facilitation of syngeneic stem cell engraftment by anti-class I monoclonal antibody pretreatment of unirradiated recipients

International Nuclear Information System (INIS)

Voralia, M.; Semeluk, A.; Wegmann, T.G.

1987-01-01

We have established a murine model of syngeneic bone marrow transplantation based on the use of monoclonal antibody as the sole conditioning regimen in unirradiated recipients. Administration of a single injection of monoclonal antibody directed against major histocompatibility complex-encoded class I determinants facilitated permanent hemopoietic stem cell engraftment without any apparent side-effects. Whereas untreated hosts exhibited a maximal chimerism of 15% at donor cell doses of up to 12 X 10(7) bone marrow cells, pretreatment by 2 mg of anti-class I antibody one week prior to transplantation of 3 X 10(7) syngeneic bone marrow cells resulted in a mean donor representation of about 80%. The antibody can be given up to four weeks prior to transplantation, and the degree of donor engraftment observed is a function of the dose of antibody administered. The fact that specific antibody enhanced engraftment in two strain combinations indicates that antibody is the active agent in facilitating engraftment and that facilitation is not strain-restricted. Anti-class I antibodies of the IgG2a, but not IgG1, isotype are effective in promoting engraftment. Although the isotype requirement suggests a role for antibody-mediated cytotoxicity in promoting stem cell engraftment, the extensive time-frame of facilitation suggests that other effects of the antibody may also be involved. The model of syngeneic bone marrow transplantation we describe here will be useful in studying the mechanisms regulating stem cell engraftment and may have potential clinical application as an approach to autologous marrow transplantation

Thymectomized, irradiated, and bone marrow-reconstituted chimeras have normal cytolytic T lymphocyte precursors but a defect in lymphokine production

International Nuclear Information System (INIS)

Duprez, V.; Maziarz, R.; Weinberger, O.; Burakoff, S.J.

1984-01-01

A model system has been developed to study extrathymic T cell differentiation; mice have been thymectomized, lethally irradiated, and reconstituted with bone marrow cells depleted of Thy-1 + cells. After 8 wk, the spleen cells of these athymic, bone marrow-reconstituted chimeras contain Thy-1 + precytolytic T lymphocytes (CTL) that are able to respond to antigen only if supernatant from Con A-activated T cells is added to culture. The phenotype of these pre-CTL is similar to that of thymocytes, suggesting that they may be immature T cells. Initial evaluation of the CTL repertoire of these athymic mice demonstrated that the CTL generated to trinitrophenyl-modified syngeneic cells are H-2-restricted, and that the CTL generated to alloantigens have many of the cross-reactivities observed in normal mice but not in nude mice. In this report, the authors demonstrate a helper T cell defect in these thymectomized chimeras. These chimeras lack an Ly-1 + helper cell required for thymocytes to differentiate to CTL. Further studies revealed that when spleen cells from these thymectomized chimeras were stimulated with Con A, they produced normal levels of interleukin 2. However, these splenocytes were defective in the production of another factor needed for CTL differentiation

Immune reactivity after high-dose irradiation

International Nuclear Information System (INIS)

Gassmann, W.; Wottge, H.U.; von Kolzynski, M.; Mueller-Ruchholtz, W.

1986-01-01

Immune reactivity after total-body irradiation was investigated in rats using skin graft rejection as the indicator system. After sublethal irradiation with 10.5 Gy (approximately 50% lethality/6 weeks) the rejection of major histocompatibility complex allogeneic skin grafts was delayed significantly compared with nonirradiated control animals (28 versus 6.5 days). In contrast, skin grafts were rejected after 7.5 days in sublethally irradiated animals and 7 days in lethally irradiated animals if additional skin donor type alloantigens--namely, irradiated bone marrow cells--were given i.v. either simultaneously or with a delay of not more than 24 hr after the above conditioning regimen. These reactions were alloantigen-specific. They were observed in six different strain combinations with varying donors and recipients. Starting on day 2 after irradiation, i.v. injection of bone marrow gradually lost its effectivity and skin grafts were no longer rejected with uniform rapidity; skin donor marrow given on days 4 or 8 did not accelerate skin graft rejection at all. These data show that for approximately 1-2 days after high-dose total-body irradiation rats are still capable of starting a vigorous immune reaction against i.v.-injected alloantigens. The phenomenon of impaired rejection of skin grafted immediately after high-dose irradiation appears to result from the poor accessibility of skin graft alloantigens during the early postirradiation phase when vascularization of the grafted skin is insufficient

Repair in schizosaccharomyces pombe as measured by recovery from caffeine enhancement of radiation-induced lethality

International Nuclear Information System (INIS)

Gentner, N.E.; Werner, M.M.

1975-01-01

Inhibition of DNA repair by caffeine is manifested in Schizosaccharomyces pombe wild-type cells as an enhancement of UV- or γ-irradiation-induced lethality. The progress of DNA repair processes involving one or more caffeine-sensitive steps may be conveniently followed by measuring the concomitant decrease of this lethal enhancement effect. By measuring, during post-irradiation incubation, the ability of cells to overcome susceptibility to repair inhibition by caffeine, we have determined the time course and requirements for repair in S. pombe. Recovery began immediately and took 150-200 min after γ-irradiation and more than 500 min after UV-irradiation, for exposures which gave about 10% survival in the absence of caffeine. An incubation medium capable of supporting growth was required for caffeine-sensitive repair; no recovery occurred under liquid holding conditions. Survival curves after various recovery times indicated that a logarithmic phase cell population was homogeneous with respect to caffeine-sensitive repair of both UV- and γ-ray-induced damage. Recovery from caffeine inhibition was compared for cells of different physiological states (logarithmic and stationary phase); although the importance of the physiological state was not the same for the two types of radiation, recovery was found to occur more rapidly in the more radiation-resistant state, in each case. (orig.) [de

An inhibitor of potentially lethal damage (PLD) repair reduces the frequency of γ-ray mutations in cultured Chinese hamster V79 cells

International Nuclear Information System (INIS)

Yokoiyama, A.; Kada, T.; Kuroda, Y.

1992-01-01

Cordycepin (3'-deoxyadenosine, 3 - dA) is an RNA antimetabolite and a radiosensitizer in cultured mammalian cells. In the present paper, the effects of 3'-dA on γ-ray-induced lethality and 6-thioguanine (6TG)-resistant mutations in cultured Chinese hamster V79 cells were examined. 3'-dA had the effect of sensitizing the lethality induced by γ-rays. The potentially lethal damage (PLD) repair produced by post-incubation cells in Hanks' solution after γ-irradiation was almost completely suppressed by 5x10 -5 M 3'-dA. When cells were irradiated with 10 Gy γ-rays and incubated with 3'-dA for 5 h, the frequency of 6TG-resistant mutations induced by γ-rays decreased to 1/6 of that of the irradiated cells incubated without 3'-dA. The decrease in the frequency of γ-ray-induced mutations was dependent on the length of incubation time with 3'-dA. It is suggested that the inhibition of PLD repair by 3'-dA may be that of error-prone repair. (author). 26 refs.; 5 figs

Oncolytic adenovirus targeting cyclin E overexpression repressed tumor growth in syngeneic immunocompetent mice

International Nuclear Information System (INIS)

Cheng, Pei-Hsin; Rao, Xiao-Mei; Wechman, Stephen L.; Li, Xiao-Feng; McMasters, Kelly M.; Zhou, Heshan Sam

2015-01-01

Clinical trials have indicated that preclinical results obtained with human tumor xenografts in mouse models may overstate the potential of adenovirus (Ad)-mediated oncolytic therapies. We have previously demonstrated that the replication of human Ads depends on cyclin E dysregulation or overexpression in cancer cells. ED-1 cell derived from mouse lung adenocarcinomas triggered by transgenic overexpression of human cyclin E may be applied to investigate the antitumor efficacy of oncolytic Ads. Ad-cycE was used to target cyclin E overexpression in ED-1 cells and repress tumor growth in a syngeneic mouse model for investigation of oncolytic virotherapies. Murine ED-1 cells were permissive for human Ad replication and Ad-cycE repressed ED-1 tumor growth in immunocompetent FVB mice. ED-1 cells destroyed by oncolytic Ads in tumors were encircled in capsule-like structures, while cells outside the capsules were not infected and survived the treatment. Ad-cycE can target cyclin E overexpression in cancer cells and repress tumor growth in syngeneic mouse models. The capsule structures formed after Ad intratumoral injection may prevent viral particles from spreading to the entire tumor. The online version of this article (doi:10.1186/s12885-015-1731-x) contains supplementary material, which is available to authorized users

Occurrence and elimination of sites sensitive to UV-endonuclease in UV-irradiated E. coli cells

Energy Technology Data Exchange (ETDEWEB)

Kleibl, K; Sedliakova, M [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Vyskumny Ustav Onkologicky

1979-01-01

The occurrence and elimination of sites sensitive to the endonucleolytic action of crude extract from M. luteus (Es sites) were studied in both the parental and daughter DNA of E. coli B/r Hcr/sup +/ irradiated either with lethal fluence only (LF) or with inducing and lethal fluence (IF+LF); after the lethal fluence protein synthesis could either take place or it was inhibited by chlorampehnicol (CAP). The data obtained showed that in the wild type UV-irradiated cells Es sites could be eliminated from their DNA molecules either through pyrimidine dimer excision or through the modification of dimers on replication. It appears that DNA repair takes place most efficiently in cells irradiated with IF+LF and postincubated with CAP; in these conditions cells are supplied with inducible proteins, and enough time for DNA repair is provided before the division of irradiated cells is resumed.

Factors controlling the recirculation of haematopoietic stem cells

International Nuclear Information System (INIS)

Petrov, R.V.; Khaitov, R.M.; Alejnikova, N.V.; Gulak, L.V.

1976-01-01

Influence of thymectomy on the rate of migration and differentiation of haematopoietic stem cells from a shielded part of the bone marrow has been studied on mice X-irradiated with a lethal dose. Inhibition of the migration rate and delay in differentiation of stem cells into colonies of granuloid type have been detected in the thymectomized mice. Transplantation of syngeneic cells of the thymus or lymph nodes to thymectomized mice increases the number of colonies in the spleen and restores the routine way of differentiation of haematopoietic stem cells. It is concluded that the processes of migration and differentiation of haematopoietic stem cells are thymus-dependent

Lethality Index 2008-2014: Less shootings, same lethality, more opacity

Directory of Open Access Journals (Sweden)

Carlos Silva Forné

2017-11-01

Full Text Available This article evaluates the use of lethal force by Mexican federal security forces during shootings with presumed members of organized crime from 2008-2014. The authors use official data and press reports on deaths and wounded in shootings to construct indicators such as the number of dead civilians over the number of dead officials from the federal security forces and the number of dead civilians over the number of wounded civilians. In a context where certain factors that contribute to an excessive use of force become more common, the results of the study show a growing use of lethal force. This raises questions over the possible excessive use of lethal force as a normal or systematic practice. The study also shows a growing context of opacity in the information available to evaluate the use of lethal force and the general lack of a legal framework to regulate the use of lethal force in Mexico.

Bone marrow-derived T lymphocytes responsible for allograft rejection

International Nuclear Information System (INIS)

Senjanovic, M.; Marusic, M.

1984-01-01

Lethally irradiated mice reconstituted with syngeneic bone marrow cells were grafted with allogeneic skin grafts 6-7 weeks after irradiation and reconstitution. Mice with intact thymuses rejected the grafts whereas the mice thymectomized before irradiation and reconstitution did not. Thymectomized irradiated mice (TIR mice) reconstituted with bone marrow cells from donors immune to the allografts rejected the grafts. Bone marrow cells from immunized donors, pretreated with Thy 1.2 antibody and C', did not confer immunity to TIR recipients. To determine the number of T lymphocytes necessary for the transfer of immunity by bone marrow cells from immunized donors, thymectomized irradiated mice were reconstituted with nonimmune bone marrow cells treated with Thy 1.2 antibody and C' and with various numbers of splenic T lymphocytes from nonimmune and immune donors. Allogeneic skin graft rejection was obtained with 10(6) nonimmune or 10(4) immune T cells. The effect of immune T cells was specific: i.e., immune T cells accelerated only rejection of the relevant skin grafts whereas against a third-party skin grafts acted as normal T lymphocytes

Comparison of six different models describing survival of mammalian cells after irradiation

International Nuclear Information System (INIS)

Sontag, W.

1990-01-01

Six different cell-survival models have been compared. All models are based on the similar assumption that irradiated cells are able to exist in one of three states. S A is the state of a totally repaired cell, in state S C the cell contains lethal lesions and in state S b the cell contains potentially lethal lesions i.e. those which either can be repaired or converted into lethal lesions. The differences between the six models lie in the different mathematical relationships between the three states. To test the six models, six different sets of experimental data were used which describe cell survival at different repair times after irradiation with sparsely ionizing irradiation. In order to compare the models, a goodness-of-fit function was used. The differences between the six models were tested by use of the nonparametric Mann-Whitney two sample test. Based on the 95% confidence limit, this required separation into three groups. (orig.)

Effects of 60Co irradiation on the genetics of indian meal moth

International Nuclear Information System (INIS)

Yang Changju; Liu Ganming; Deng Wangxi; Yang Zhihui; Hu Jianfang

1993-01-01

4 ∼ 5 days old male pupae of Indian meal moth, Plodia interpunctella Hubner were irradiated with 1, 3, 5, 7 and 10 krad of 60 Co γ-ray. The male moths developed from treated pupae and their F 1 generation were put together with normal female moths for copulation separately. The genetic effects of irradiation was studied and the results showed that the effects of irradiation were significant, which related to the irradiation dosage, on both parental and filial generations. Only 40% of the pupae was emerged, when they were irradiated at 10 krad. The effects on deformation rates, survival rates, copulation abilities, fecundities, hatching rates and genetic sterilities varied with different irradiation dosage treatment. With consideration of the total irradiation effect, the dosage lower than 5 krad is desirable for inducing the sterility of adults and sex chain recessive lethal gene. With 1, 5 and 7 krad of irradiation, a mutant of P. interpunctella with transparent wings was induced, which provides a marking feature in control of Indian meal moth by sex chain recessive lethal gene

Genetic effects of feeding irradiated wheat to mice

International Nuclear Information System (INIS)

Vijayalaxmi

1976-01-01

The effects of feeding irradiated wheat in mice on bone marrow and testis chromosomes, germ cell numbers and dominant lethal mutations were investigated. Feeding of freshly irradiated wheat resulted in significantly increased incidence of polyploid cells in bone marrow, aneuploid cells in testis, reduction in number of spermatogonia of types A, B and resting primary spermatocytes as well as a higher mutagenic index. Such a response was not observed when mice were fed stored irradiated wheat. Also there was no difference between the mice fed un-irradiated wheat and stored irradiated wheat. (author)

Induced pluripotent stem cell-derived gamete-associated proteins incite rejection of induced pluripotent stem cells in syngeneic mice.

Science.gov (United States)

Kim, Eun-Mi; Manzar, Gohar; Zavazava, Nicholas

2017-06-01

The safety of induced pluripotent stem cells (iPSCs) in autologous recipients has been questioned after iPSCs, but not embryonic stem cells (ESCs), were reported to be rejected in syngeneic mice. This important topic has remained controversial because there has not been a mechanistic explanation for this phenomenon. Here, we hypothesize that iPSCs, but not ESCs, readily differentiate into gamete-forming cells that express meiotic antigens normally found in immune-privileged gonads. Because peripheral blood T cells are not tolerized to these antigens in the thymus, gamete-associated-proteins (GAPs) sensitize T cells leading to rejection. Here, we provide evidence that GAPs expressed in iPSC teratomas, but not in ESC teratomas, are responsible for the immunological rejection of iPSCs. Furthermore, silencing the expression of Stra8, 'the master regulator of meiosis', in iPSCs, using short hairpin RNA led to significant abrogation of the rejection of iPSCs, supporting our central hypothesis that GAPs expressed after initiation of meiosis in iPSCs were responsible for rejection. In contrast to iPSCs, iPSC-derivatives, such as haematopoietic progenitor cells, are able to engraft long-term into syngeneic recipients because they no longer express GAPs. Our findings, for the first time, provide a unifying explanation of why iPSCs, but not ESCs, are rejected in syngeneic recipients, ending the current controversy on the safety of iPSCs and their derivatives. © 2017 John Wiley & Sons Ltd.

Hygiene assessment of irradiated potato mutagenic activity

International Nuclear Information System (INIS)

Uralova, M.; Grunt, J.; Patzeltova, N.

1977-01-01

Albino rat males were fed on gamma-irradiated potatoes for one month and mated with two intact female rats each. The dominant lethal mutation method was then used for the study of possible mutagenic activity of the irradiated potatoes. No statistically significant differences were observed and no mutagenic activity was found. Thus, the test showed that potatoes irradiated with a dose of 10 krad of gamma radiation does not present genetic hazards for albino rats. (L.O.)

Repair of membrane damage in X-irradiated E. coli

International Nuclear Information System (INIS)

Gillies, N.E.; Ratnajothi, N.H.; Hewamanna, R.; Obioha, F.I.

1984-01-01

When E. coli B/r or E. coli K12 AB1157 were X-irradiated in the presence of oxygen and incubated immediately after irradiation in broth containing penicillin in concentration that on its own was not lethal to unirradiated bacteria, substantial additional killing was caused. When treatment with penicillin was delayed for increasing times after irradiation the additional killing became progressively less. These results were interpreted as demonstrating the repair or removal of oxygen-dependent radiation-induced lesions in the bacterial membranes. Removal of these lesions was inhibited by incubation of the irradiated bacteria at low temperature before treatment with penicillin or by exposing the cells to a non-lethal concentration of toluene before irradiation. These observations suggest that an enzymatic repair process may be involved in the removal of the membrane lesions. The fatty acid mutant E. coli K 1060 proved exceptional in that some additional killing by penicillin was detectable after anaerobic as well as aerobic irradiation. This points to the importance of membrane composition in the development of those radiation lesions that are brought to light by penicillin treatment. (author)

Pedigree analyses of yeast cells recovering from DNA damage allow assignment of lethal events to individual post-treatment generations

International Nuclear Information System (INIS)

Klein, F.; Karwan, A.; Wintersberger, U.

1990-01-01

Haploid cells of Saccharomyces cerevisiae were treated with different DNA damaging agents at various doses. A study of the progeny of individual such cells allowed the assignment of lethal events to distinct post treatment generations. By microscopically inspecting those cells which were not able to form visible colonies the authors could discriminate between cells dying from immediately effective lethal hits and those generating microcolonies probably as a consequence of lethal mutation(s). The experimentally obtained numbers of lethal events were mathematically transformed into mean probabilities of lethal fixations at taking place in cells of certain post treatment generations. Such analyses give detailed insight into the kinetics of lethality as a consequence of different kinds of DNA damage. For example, X-irradiated cells lost viability mainly by lethal hits, only at a higher dose also lethal mutations fixed in the cells that were in direct contact with the mutagen, but not in later generations, occurred. Ethyl methanesulfonate (EMS)-treated cells were hit by 00-fixations in a dose dependent manner. The distribution of all sorts of lethal fixations taken together, which occurred in the EMS-damaged cell families, was not random. For comparison analyses of cells treated with methyl methanesulfonate, N-methyl-N'-nitro-N-nitrosoguanidine and nitrous acid are also reported

Anti-bacterial immunity to Listeria monocytogenes in allogeneic bone marrow chimera in mice

International Nuclear Information System (INIS)

Onoe, K.; Good, R.A.; Yamamoto, K.

1986-01-01

Protection and delayed-type hypersensitivity (DTH) to the facultative intracellular bacterium Listeria monocytogenes (L.m.) were studied in allogeneic and syngeneic bone marrow chimeras. Lethally irradiated AKR (H-2k) mice were successfully reconstituted with marrow cells from C57BL/10 (B10) (H-2b), B10 H-2-recombinant strains or syngeneic mice. Irradiated AKR mice reconstituted with marrow cells from H-2-compatible B10.BR mice, [BR----AKR], as well as syngeneic marrow cells, [AKR----AKR], showed a normal level of responsiveness to the challenge stimulation with the listeria antigens when DTH was evaluated by footpad reactions. These mice also showed vigorous activities in acquired resistance to the L.m. By contrast, chimeric mice that had total or partial histoincompatibility at the H-2 determinants between donor and recipient, [B10----AKR], [B10.AQR----AKR], [B10.A(4R)----AKR], or [B10.A(5R)----AKR], were almost completely unresponsive in DTH and antibacterial immunity. However, when [B10----AKR] H-2-incompatible chimeras had been immunized with killed L.m. before challenge with live L.m., these mice manifested considerable DTH and resistance to L.m. These observations suggest that compatibility at the entire MHC between donor and recipient is required for bone marrow chimeras to be able to manifest DTH and protection against L.m. after a short-term immunization schedule. However, this requirement is overcome by a preceding or more prolonged period of immunization with L.m. antigens. These antigens, together with marrow-derived antigen-presenting cells, can then stimulate and expand cell populations that are restricted to the MHC (H-2) products of the donor type

Potentially lethal damage and its repair

International Nuclear Information System (INIS)

Utsumi, Hiroshi

1989-01-01

Two forms termed fast-and slow-potentially lethal lethal damage (PLD) are introduced and discussed. The effect on the survival of x-irradiated Chinese hamster cells (V79) of two different post-treatments is examined in plateau- and in log-phases of growth. The postirradiation treatments used : a) incubation in hypertonic solution, and b) incubation in conditioned medium obtained from plateau-phase. Similar reduction in survival was caused by postirradiation treatment with hypertonic phosphate buffered saline, and similar increased in survival was effected by treatment in conditioned medium in plateau- and in log-phases cells. However, repair of PLD sensitive to hypertonic treatment was faster (half time, 5-10 min)(f-PLD repair) and independent from the repair of PLD (half time, 1-2 hour)(s-PLD repair) observed in conditioned medium. The results indicate the induction of two forms of PLD by radiation. Induction of both PLD was found to decrease with increasing LET of the radiation used. Identification of the molecular processes underlying repair and fixation of PLD is a task of particular interest, since it may allow replacement of a phenomenological definition with a molecular definition. Evidence is reviewed indicating the DNA double strand breaks (directly or indirectly induced) may be the DNA lesions underlying PLD. (author)

Comparison of Allogeneic and Syngeneic Rat Glioma Models by Using MRI and Histopathologic Evaluation.

Science.gov (United States)

Biasibetti, Elena; Valazza, Alberto; Capucchio, Maria T; Annovazzi, Laura; Battaglia, Luigi; Chirio, Daniela; Gallarate, Marina; Mellai, Marta; Muntoni, Elisabetta; Peira, Elena; Riganti, Chiara; Schiffer, Davide; Panciani, Pierpaolo; Lanotte, Michele

2017-03-01

Research in neurooncology traditionally requires appropriate in vivo animal models, on which therapeutic strategies are tested before human trials are designed and proceed. Several reproducible animal experimental models, in which human physiologic conditions can be mimicked, are available for studying glioblastoma multiforme. In an ideal rat model, the tumor is of glial origin, grows in predictable and reproducible patterns, closely resembles human gliomas histopathologically, and is weakly or nonimmunogenic. In the current study, we used MRI and histopathologic evaluation to compare the most widely used allogeneic rat glioma model, C6-Wistar, with the F98-Fischer syngeneic rat glioma model in terms of percentage tumor growth or regression and growth rate. In vivo MRI demonstrated considerable variation in tumor volume and frequency between the 2 rat models despite the same stereotactic implantation technique. Faster and more reproducible glioma growth occurred in the immunoresponsive environment of the F98-Fischer model, because the immune response is minimized toward syngeneic cells. The marked inability of the C6-Wistar allogeneic system to generate a reproducible model and the episodes of spontaneous tumor regression with this system may have been due to the increased humoral and cellular immune responses after tumor implantation.

Uptake of carbon monoxide by C3H mice following X irradiation of lung only or total-body irradiation with 60Co

International Nuclear Information System (INIS)

Rappaport, D.S.; Niewoehner, D.E.; Kim, T.H.; Song, C.W.; Levitt, S.H.

1983-01-01

Carbon monoxide uptake (V/sub co/) and ventilation rate (VR) of C3H mice were determined at 14 weeks following either X irradiation of lungs only or total-body irradiation with 60 Co at different dose rates. Following localized X irradiation of lung at 97 /sub c/Gy/min there was a reduction in V/sub co/, which was inversely related to radiation dose, with a small reduction below control levels being detected at 7 Gy, the lowest dose tested. An increase in VR could be detected only at doses of 11 Gy, or more. Another group of animals received 11.5 Gy total-body irradiation at either 26.2 or 4.85 /sub c/Gy/min fllowed by transplantation with syngeneic bone marrow. Following total-body irradiation, V/sub co/ was significantly reduced by about 37% at the higher dose rate and 23% at the lower dose rate. In contrast, a trend toward elevated VR was detected only at the higher dose rate.The results indicate that V/sub co/ is a sensitive indicator of radiation-induced lung injury and that under the experimental conditions used V/sub co/ is a more sensitive indicator of radiation-induced lung injury in C3H mice than VR

The Evolutionary Relationships between Endosymbiotic Green Algae of Paramecium bursaria Syngens Originating from Different Geographical Locations.

Science.gov (United States)

Zagata, Patrycja; Greczek-Stachura, Magdalena; Tarcz, Sebastian; Rautian, Maria

2016-01-01

Paramecium bursaria (Ehrenberg 1831), a freshwater ciliate, typically harbors hundreds of green algal symbionts inside the cell. The aim of present study was the molecular identification of newly analyzed P. bursaria symbionts. The second aspect of the present survey was testing a hypothesis whether endosymbionts prefer the specified syngen of the host, and the specified geographical distribution. Ten strains of endosymbionts isolated from strains of P. bursaria originating from different geographical locations were studied. We analyzed for the first time, both the fragment of plastid genome containing 3'rpl36-5' infA genes and a fragment of a nuclear gene encoding large subunit ribosomal RNA (LSU rDNA). The analysis of the LSU rDNA sequences showed the existence of 3 haplotypes and the haplotype diversity of 0.733, and 8 haplotypes for the 3'rpl36-5' infA gene fragment and haplotype diversity of 0.956. The endosymbionts isolated from P. bursaria strains were identified as Chlorella vulgaris, Ch. variabilis and Micractinium conductrix. There was no correlation between the syngen of P. bursaria and the species of endosymbiont.

Preoperative irradiation of hypernephroid carcinoma

International Nuclear Information System (INIS)

Akbar, D.

1982-01-01

Since 1969, preoperative irradiation of hypernephiroid carcinoma has been a routine measure at the Steglitz medical clinic: It consists in the application of a focal dose of 30 Gy, fractionated into doses of 2.5 Gy, as Betatron pendulum irradiation (42 MeV photons) covering the para-aortic lymph nodes. After a treatment-free interval of 3 weeks, radical nephrectomy is carried through. Of 178 patients, 47 were in tumor stage I, 15 in stage II, 83 in stage III and 33 in stage IV. In 99 patients the treatment dated back longer than 5 years; the survival rate was 52%. 67% of the patients had survived longer than 3 years. Operation lethality was 3%. The preoperative irradiation pursues the following aims: 1. Devitalization of potentially proliferating cells in the tumor periphery, and thus prevention of displaced tumor cells growing on and postoperative local recidivations; 2. Shrinking of the tumor, facilitating the surgical intervention. In a third of the cases a measurable alteration of the tumor was confirmed by X-ray. The low operation lethality of 3% is attributed to this. (orig./MG) [de

Hyperthermic radiosensitization of synchronous Chinese hamster cells: relationship between lethality and chromosomal aberrations

International Nuclear Information System (INIS)

Dewey, W.C.; Sapareto, S.A.; Betten, D.A.

1978-01-01

Synchronous Chinese hamster cells in vitro were obtained by mitotic selection. The cells were heated at 45.5 0 C for 4 min in mitosis, 11 min in G 1 , or 7 min in S sphase and then x-irradiated immediately thereafter. Colony survival from heat alone was 0.30 to 0.45, and the frequency of chromosomal aberrations induced by heat was 0.00, 0.14, or 0.97 for heat treatments during M, G 1 , or S, respectively. As shown previously, lethality from hyperthermia alone is due to chromosomal aberrations only when the cells are heated during S phase. The log survival (D 0 /sup approximately/ = 80 rad) and aberration frequency curves for cells irradiated during mitosis were linear, and the only effect of hyperthermia was to shift the curves in accord with the effect from heat alone. Thus, hyperthermia did not radiosensitize the mitotic cells. The cells irradiated in G 1 were more resistant (D 0 /sup approximately/ = 100 rad) than those irradiated in mitosis, and the survival and aberration frequency curves both had shoulders. The primary effect of hyperthermia was to greatly reduce the shoulders of the curves and to increase the slopes by about 23%. The cells irradiated in S were the most resistant (D 0 /sup approximately/ = 140 rad), and the survival and aberration frequency curves both had large shoulders. For both end points of lethality and chromosomal aberrations, heat selectively radiosensitized S-phase cells relative to G 1 cells by removing most of the shoulder and increasing the slope by about 45%. For cells treated in G 1 or S, the increase in radiosensitization following hyperthermia can be accounted for by an increase in the frequency of chromosomal aberrations

Mutagenesis of the somaclones in vitro of cut roses by 60Co γ-rays irradiation

International Nuclear Information System (INIS)

Qu Suping; Su Yan; Wang Lihua; Tang Kaixue; Wang Jihua; Zhang Hao

2009-01-01

Mutagenesis of cut rose in vitro irradiated by 60 Co γ-rays was studied. The callus of leaves and regenerations adventitious bud was used as the explants for mutagenesis. Effect of 60 Co γ-rays irradiation on the callus's regeneration rate, adventitious bud's multiplication rate and vegetal status were studied. The results showed that the regeneration frequency of callus was decreased by 60 Co γ-rays irradiation. The regenerations adventitious bud was the better experimental materials compared with the callus of leaves. The lethal dose was 122 Gy and the semi-lethal dose was 76 Gy according to the regression equation. The appropriate dose on adventitious bud by irradiation rays was 50-60 Gy. (authors)

Histopathological effects of lethal and sub-lethal concentrations of ...

African Journals Online (AJOL)

The histopathological effects of lethal and sub-lethal concentrations of glyphosate on African catfish Clarias gariepinus were investigated. C. gariepinus juveniles were assessed in a static renewal bioassay for 96 hours (acute toxicity) and 28 days (chronic toxicity) using varying concentrations (0.0 mg/l 20.0 mg/l, 30.0 mg/l, ...

Comparative study of different sexis mutability: recessive sex-linked and dominant lethals in Drosophila melanogaster

International Nuclear Information System (INIS)

Vatti, K.V.; Dzhaparidze, L.A.; Mamon, L.A.

1980-01-01

The frequency of recessive sex-linked lethal mutations (RSLLM) and those realizing in embryogenesis of dominant lethals, which form in oo- and spermatogenesis of Drosophila and fly productivity under the effect of X-rays and N-nitroso-N methylourea (NMU), is studied. In the case of effect of both mutagens RSLLM form in spermatocytes with higher frequency as compared with oocytes. Dominant lethal mutations (DLM) during irradiation are also often registered in spermatocytes. NMU induces DLM in mitotic male cells with a very high frequency but is not effective during the effect on oocytes. When both mutagens affect males and X-rays affect females, the decrease of productivity is mainly conditioned by DLM. As NMU does not induce DLM in females realizing in embryogenesis but reduces productivity, a later lethal realization connected with their different nature is supposed. Differences in mole and female mutability found in the course of X-ray and NMU effect are discussed in connection with peculiarities of their mitotic cells and the nature of effect of mutagens applied [ru

Repair of potentially lethal damage following irradiation with x rays or cyclotron neutrons: response of the EMT-6/UW tumor system treated under various growth conditions in vitro and in vivo

International Nuclear Information System (INIS)

Rasey, J.S.; Nelson, N.J.

1981-01-01

Postirradiation potentially lethal damage (PLD) repair was examined in the EMT-6/UW tumor system under a variety of in vitro and in vivo growth conditions. Following x irradiation, surviving fraction increased in fed and unfed plateau cultures if subculture and plating were delayed; in exponentially growing cultures if they were covered with depleted medium for the first 6 h postirradiation; and in tumors in vivo if excision for preparation of a cell suspension was delayed. Following irradiation with 21.5 meV (d + → Be) neutrons, PLD repair was measurable only in unfed plateau cultures when subculture was delayed and in exponentially growing cells exposed to depleted culture medium immediately after irradiation. In x-irradiated EMT-6/UW cells, the greatest repair capacity and the highest surviving fraction ratios were measured in unfed plateau cultures; the least repair was observed in exponentially growing cells exposed to depleted medium. Thus post-neutron repair was not limited to situations where the amount of repair of photon PLD is large. The demonstration of PLD repair in tumors irradiated in vivo with X rays and the absence of such repair after neutrons could have important implications in radiotherapy if this is a general phenomenon

Attenuation of primary nonfunction for syngeneic islet graft using sodium 4-phenylbutyrate.

Science.gov (United States)

Fu, S-H; Chen, S-T; Hsu, B R-S

2005-05-01

Sodium 4-phenylbutyrate (4-SPB), an aromatic derivative of butyric acid, was examined to elucidate its effect on islet engraftment in a syngeneic transplantation model using C57BL/6 mice. Diabetic mice that received subrenal implantation of 150 islets on day 0 and oral administration of twice daily 4-SPB (500 mg/kg body weight) on days -2 through 28 displayed a significantly shorter duration of posttransplantation temporary hyperglycemia than diabetic mice that received islets in isotonic sodium chloride solution (NaCl), namely 16 +/- 2 (n = 12) vs 23 +/- 2 days (n = 7; P < .05). Four weeks after transplantation, the insulin content (IC) of grafts from mice treated with islets and 4-SPB was substantially higher than that of grafts from mice treated with islets and NaCl, namely 2.59 +/- 0.37 (n = 8) vs 1.36 +/- 0.36 mug (n = 13; P < .01). The IC of pancreatic remnants showed no significant difference between groups after 2 and 4 weeks of incubation. In vitro studies demonstrated that the net glucose-stimulated insulin secretion (GSIS) and the ratio of net GSIS to the IC of islets cultured with 4-SPB (1 mM) did not differ significantly from those cultured with NaCl. The lipopolysaccharide-stimulated secretions of IL-1beta, IL-10, and IFNgamma from peritoneal exudate monocytes were significantly reduced by co-incubation with 4-SPB (1 mM). In conclusion, our data suggest that daily administration of 4-SPB reduces primary nonfunction and enhances islet engraftment in a syngeneic mouse transplantation model.

Enhanced sensitivity to the lethal and mutagenic effects of photosensitizing action of chlorpromazine in ethylenediaminetetraacetate-treated Escherichia coli

International Nuclear Information System (INIS)

Yonei, S.; Todo, T.

1982-01-01

Ethylenediaminetetraacetate (EDTA) treatment of Escherichia coli H/r30 (Arg - ) enhanced cell sensitivity to the lethal and mutagenic effects of the photosensitizing action of chlorpromazine (CPZ). The most obvious effect of EDTA on the fluence-survival curve was an elimination of the shoulder. In the absence of EDTA, CPZ plus near-UV radiation did not induce the reversion from arginine-auxotroph to autotroph of E. coli H/r30. However, when EDTA (5 mM)-treated cells were subjected to CPZ plus near-UV radiation, the induced reversion frequency increased with time of irradiation. It is concluded that the enhanced penetration of CPZ into E. coli cells by EDTA facilitates the drug binding to DNA within the cells upon near-UV irradiation and that this is the cause for the enhanced photosensitized lethal and mutagenic effects of CPZ. (author)

Effects of nutritional status on gastric secretion and composition in X-irradiated rat

International Nuclear Information System (INIS)

D'Souza, D.W.; Vakil, U.K.; Sreenivasan, A.

1974-01-01

Whole body x-irradiation of the rat with a sub-lethal (400 r) or lethal (800 r) dose causes a marked depression in secretion and composition of gastric juice with a maximum drop of the 8th day. Similarly, pepsin and gastricsin activities also decline progressively, being lowest on the 8th day post-irradiation. Radiation exposure of the rat also results in a sudden rise in serum and tissue histamine levels which occurs on the 1st day, and returns to normal on the 3rd day post-irradiation. The nutritional status of the animal appears to influence recovery from radiation injury. Rats fed adequate diets with respect to protein and vitamin A prior to irradiation (400 r) recover earlier from radiation injury than deficient animals. The above biochemical changes are associated with gross and severe degeneration of stomach cells in the x-irradiated rat. (author)

Necrostatin-1 rescues mice from lethal irradiation.

Science.gov (United States)

Huang, Zhentai; Epperly, Michael; Watkins, Simon C; Greenberger, Joel S; Kagan, Valerian E; Bayır, Hülya

2016-04-01

There is an emerging need in new medical products that can mitigate and/or treat the short- and long-term consequences of radiation exposure after a radiological or nuclear terroristic event. The direct effects of ionizing radiation are realized primarily via apoptotic death pathways in rapidly proliferating cells within the initial 1-2days after the exposure. However later in the course of the radiation disease necrotic cell death may ensue via direct and indirect pathways from increased generation of pro-inflammatory cytokines. Here we evaluated radiomitigative potential of necrostatin-1 after total body irradiation (TBI) and the contribution of necroptosis to cell death induced by radiation. Circulating TNFα levels were increased starting on d1 after TBI and associated with increased plasmalemma permeability in ileum of irradiated mice. Necrostatin-1 given iv. 48h after 9.5Gy TBI attenuated radiation-induced receptor interacting protein kinase 3 (RIPK3) serine phosphorylation in ileum and improved survival vs. vehicle. Utilizing apoptosis resistant cytochrome c(-/-) cells, we showed that radiation can induce necroptosis, which is attenuated by RNAi knock down of RIPK1 and RIPK3 or by treatment with necrostatin-1 or -1s whereas 1-methyl-L-tryptophan, an indoleamine-2,3-dioxygenase inhibitor, did not exhibit radiomitigative effect. This suggests that the beneficial effect of necrostatin-1 is likely through inhibition of RIPK1-mediated necroptotic pathway. Overall, our data indicate that necroptosis, a form of programmed necrosis, may play a significant role in cell death contributing to radiation disease and mortality. This study provides a proof of principle that necrostatin-1 and perhaps other RIPK1 inhibitors are promising therapeutic agents for radiomitigation after TBI. Copyright © 2016 Elsevier B.V. All rights reserved.

Irradiation effects on the variability of yield characteristics of soybeans

International Nuclear Information System (INIS)

Pasztor, K.; Egri, K.; Toeroek, Z.; Bornemiszane, P.P.

1983-01-01

The seeds of soybean varieties 'Merit' and 'S-1346' were irradiated by fast neutrons with doses between 4 and 174 Gy. The doses in the range of 57-174 Gy proved to be lethal. After low dose irradiation, shorter breeding time and the stimulation of plant growth could be observed. The effects of irradiation on the oil and protein contents of soybeans were contradictory. (V.N.)

Interaction of radiation, Dihydroxyanthraquinone, and Adriamycin on the induction of acute lethality in mice

International Nuclear Information System (INIS)

Kimler, B.F.; Cox, G.G.; Reddy, E.K.

1984-01-01

The acute lethality induced by combinations of radiation, Dihydroxyanthraquinone (DHAQ), and Adriamycin (ADR) was investigated in mice. Whole-body irradiation produced acute lethality, with an LD-50/30 of approximately 6.5 Gy. ADR and DHAQ produced LD-50/30's of 14 and 4 mg/kg, respectively. When 10 mg/kg doses were fractionated into 5 x 2 mg/kg daily doses, both drugs were equally or more efficient at producing mortality, 90% by day 30. When 4 Gy radiation was combined with 5 mg/kg ADR or 5 mg/kg DHAQ, a response no greater than that produced by drug alone was obtained. However, when 5 mg/kg ADR was administered concomitantly with 5 mg/kg DHAQ, there was a less-than-additive induction of lethality, resulting in only 21% mortality by day 20. ADR and DHAQ (at doses of 5 mg/kg) were combined but with a 1 day interval between drugs, the protective effect was lost and animals died earlier than after either agent alone. At present, no definite explanation is available for this unusual protective effect of ADR against acute lethality induced by DHAQ

Hyperthermia radiosensitization in human glioma cells comparison of recovery of polymerase activity, survival, and potentially lethal damage repair

International Nuclear Information System (INIS)

Raaphorst, G.P.; Feeley, M.M.

1994-01-01

DNA polymerase inactivation is compared to thermal radiosensitization and inhibition of damage recovery in human glioma cells. Two human glioma cell lines (U87MG and U373MG) were exposed to hyperthermia and irradiation. Hyperthermia was given at 43 degrees C and 45 degrees C and DNA polymerase α + δ + ε and β activities were measured. Hyperthermia was given at various times before irradiation and the degree of radiosensitization and polymerase activity was assessed at various times after heating. In addition the ability of cells to undergo repair of potentially lethal radiation damage was assessed for cells irradiated at various times after heating. Polymerase α + δ + ε and polymerase β both recovered after heating but polymerase β was faster and was complete in U373MG but not in the U87MG cell lines after 48 h incubation after heating (45 degrees C, 60 min). Incubation, between hyperthermia and irradiation resulted in a loss of radiosensitization and a loss of inhibition of repair of potentially lethal damage. These changes correlated well with recovery of polymerase β but not with polymerase α + δ + ε. The correlation of polymerase β activity and thermoradiosensitization and its recovery indicate that polymerase β may be one of the mechanisms involved in thermoradiosensitization. 35 refs., 7 figs

Expression of assayable residual stem cell damage in erythroid differentiation

International Nuclear Information System (INIS)

Huebner, G.E.; Miller, M.E.; Cronkite, E.P.

1985-01-01

In rodents, residual damage is inducible in hematopoietic stem cells by exposure to ionizing radiation or alkylating agents. This damage can b e assayed in mice by transferring bone marrow into lethally irradiated syngeneic recipients and subsequently measuring the incremental increase of-( 125 I)iodo-2'-deoxyuridine incorporation in spleens. In this study, bone marrow from mice treated 3 weeks previously with Methylnitrosourea (50 mg/kg) or 450 rad was injected into recipients in order to determine possible residual effects of treatment of erythroid cell differentiation following stem cell seeding. Such effects were detected by a reduced amount of 59 Fe incorporation into spleens, thus indicatin g transfer of residual stem cell damage to differentiating cells. (orig.)

Sunlight suppressing rejection of 280- to 320-nm UV-radiation-induced skin tumors in mice

International Nuclear Information System (INIS)

Morison, W.L.; Kelley, S.P.

1985-01-01

Repeated exposure of female C3H/HeNCR- mice to sunlight prevented the normal immunologic rejection of a UV-induced tumor. This systemic immunologic alteration was transferred to syngeneic lethally X-irradiated animals with lymphoid cells from mice exposed to sunlight. The lymphoid cells also were able to suppress the capacity of lymphoid cells from normal animals to reject a UV-induced tumor. The 295- to 320-nm wave band appeared to be responsible for this immunosuppressive effect of sunlight because suppression was prevented by filtration of the radiation through Mylar and by application of a sunscreen containing para-aminobenzoic acid. These observations may have importance in understanding the pathogenesis of sunlight-induced skin cancer in humans

Long-term feeding studies in mice fed a diet containing irradiated fish. I

International Nuclear Information System (INIS)

Petten, L.E. van; Calkins, J.E.; McConnell, R.F.; Gottschalk, H.M.; Elias, P.S.

1980-01-01

A wholesomeness feeding study was carried out in mice fed equal amounts of cod or redfish, comprising 45% of the diet. Three groups of animals received either irradiated [1.75 kGy (175 krad)] fish, non-irradiated fish or stock ration. A 90-day subchronic study, a multigeneration reproduction, a dominant lethality and a teratology study were carried out together with an 80-week oncogenic study on the F 1 generation. No adverse effects were noted on growth, reproduction and litter behaviour, in relation to dominant lethality, teratogenicity or oncogenicity. (Auth.)

Biochemical aspects of the immunomodular action in irradiated survival mice with 60C gama irradiation

International Nuclear Information System (INIS)

Garcia Agudo, N.L. del M. de.

1983-01-01

The radioprotective action of Calmetti-Guerin bacillus (BCG), Corynebacterium parvum, Escherichia coli Lipopolysccharides (LPS) and peptone proteose was evaluated. A single injection of the macrophage activiting agents prior to 60 Co whole-body irradiation increased the survival rate of mice in the lethal dose range. (L.M.J.) [pt

Chemical and radiation induced late dominant lethal effects in mice

International Nuclear Information System (INIS)

Favor, J.; Crenshaw, J.W. Jr.; Soares, E.R.

1978-01-01

Although theoretically expected, experimental data to date have not shown dominant lethal expression to occur throughout the developmental period. Specifically, late post-implantation effects have not been demonstrated. The authors routinely use an experimental technique in which parental females mated to mutagenically treated males are allowed to give birth and wean their litter, and their uterine horns are then inspected for uterine scars indicative of live and dead embryos. In a number of experiments in which males were mutagenically treated with either chemicals or X-irradiation, a discrepancy was observed between the number of live embryos as determined by the scar technique and the number of live observed at birth, suggesting the possibility of embryonic losses at a late stage in development. Initial analyses showed that mutagenic treatment increased the percentage of these late losses. These differences were statistically significant in 2 of 3 analyses. Factors affecting statistical significance and an understanding of dominant lethal mutations are discussed. (Auth.)

Lethal effect after whole-body irradiation on mouse with various photon radiations

International Nuclear Information System (INIS)

Kohda, Shizuo

1976-01-01

The dependence of mortality on the quality of radiation was investigated in ICR mice after wholebody irradiation with 200 kV x-ray, 60 Co γ-ray, or 10 MV x-ray. With respect to the 30 day mortality, LD 50 values were estimated as 606 rad for 200 kV x-ray and as 713 rad both for 60 Co γ-ray and for 10 MV x-ray. Hence, the value of relative biological effectiveness (RBE) to that for 200 kV x-ray was 0.850, while the value decreased with increasing the mortality rate. The value extrapolated to 100% mortality was estimated as 0.6. These results were valid for either 7 or 8 week mice, but the life span of 7 week mice after the irradiation was 3 days shorter than that of 8 week mice. These findings resulted in following conclusions: 1) There are no qualitative differences between 10 MV x-ray and 60 Co γ-ray irradiations. 2) The biological effects after 10 MV x-ray and 60 Co γ-ray irradiations are reduced with increased killing rate, compared with that after 200 kV x-ray irradiations. (Evans, J.)

Autoradiographic studies on the cell kinetics after the whole body X-irradiation. 2. Regularities of the post-irradiation death of differentiating and proliferating cells of the rat brain subependimal zone

International Nuclear Information System (INIS)

Gracheva, N.D.

1982-01-01

A wave-like character of death of proliferating and differentiating (D) cells is shown autoradiographically using 3 H-thymidine introduced 60-80 min before the whole body X-ray irradiation in doses of 50, 150 or 300 R on subependymal cells of rat brain. Lethally damaged cells irradiated in G 2 and S-phases, resulted in 4 peaks of death in mitosis by following the first postradiational mitotic cycle (MC). Lethally damaged cells irradiated in G 1 -phase lost ability for DNA synthesis as cells irradiated in a dose of 300 R did not include additionally introduced (3 hrs before death) 14 C-thymidine from 12 to 17 hrs after 3 H-thymidine injection. However, in the first 4 hrs after irradiation there were no cells irradiated in G 1 -phase among dead ones, as indirec showed the calculations of data obtained tly/ while studying Pliss lymphosarcoma. A supposition is made that the death of cells irradiated in G 1 -phase is attributed to mitotic phase of the first MC after irradiation. Waves of death of lethally damaged D-cells repeated the peaks of death and corresponded to the mitotic peaks of proliferating cells, which permitted to presuppose the presence of ''short cycle'' (SC) in D-cells, which have the rhythm similar to MC and their death has been attributed to the final SC phase, which corresponds to MC mitotic phase in time. According to the peaks of cell death position of one hour block independent of dose in six MC(SC) points is determined. The cells have experienced the block in the point of MC(SC) in subphase of which they were caught by irradiation. Dose effect is manifested in the number of dead cells

Theories of Lethal Mutagenesis: From Error Catastrophe to Lethal Defection.

Science.gov (United States)

Tejero, Héctor; Montero, Francisco; Nuño, Juan Carlos

2016-01-01

RNA viruses get extinct in a process called lethal mutagenesis when subjected to an increase in their mutation rate, for instance, by the action of mutagenic drugs. Several approaches have been proposed to understand this phenomenon. The extinction of RNA viruses by increased mutational pressure was inspired by the concept of the error threshold. The now classic quasispecies model predicts the existence of a limit to the mutation rate beyond which the genetic information of the wild type could not be efficiently transmitted to the next generation. This limit was called the error threshold, and for mutation rates larger than this threshold, the quasispecies was said to enter into error catastrophe. This transition has been assumed to foster the extinction of the whole population. Alternative explanations of lethal mutagenesis have been proposed recently. In the first place, a distinction is made between the error threshold and the extinction threshold, the mutation rate beyond which a population gets extinct. Extinction is explained from the effect the mutation rate has, throughout the mutational load, on the reproductive ability of the whole population. Secondly, lethal defection takes also into account the effect of interactions within mutant spectra, which have been shown to be determinant for the understanding the extinction of RNA virus due to an augmented mutational pressure. Nonetheless, some relevant issues concerning lethal mutagenesis are not completely understood yet, as so survival of the flattest, i.e. the development of resistance to lethal mutagenesis by evolving towards mutationally more robust regions of sequence space, or sublethal mutagenesis, i.e., the increase of the mutation rate below the extinction threshold which may boost the adaptability of RNA virus, increasing their ability to develop resistance to drugs (including mutagens). A better design of antiviral therapies will still require an improvement of our knowledge about lethal

The oncogenic potential of three different 7, 12-dimethylbenz (a)anthracene transformed C3H/10T1/2 cell clones at various passages and the importance of the mode of immunosuppression

International Nuclear Information System (INIS)

Saxholm, H.J.K.

1979-01-01

The oncogenic potential of C3H/10T1/2 cells which were transformed in vitro with 7,12-dimethylbenz(a)anthracene is reported. The ability of the cells to grow as malignant tumors in syngeneic immunosuppressed mice was used as parameter for oncogenic potential. Cells of types I, II and III were assayed at several dosage levels, i.e., 10 4 , 10 5 or 10 6 cells per inoculum, with or without immunosuppression by antithymocyte serum globulin fraction. The studies were performed in several strains of host animals, i.e., male and female syngeneic C3H mice supplied by the National Cancer Institute, C3H mice supplied by Charles River and nude, athymic female mice. Morphological transformation preceded oncological transformation, and type I cells could not be established as tumors. Type II and type III cells developed oncogenic potential only after several passages in culture. Oncogenic potential was pronounced in the type III cells, and less strongly expressed in type II cells. Also tested were different methods of immunosuppression of the animal against the expression of the oncogenic potential of DMBA transformed C3H/10T1/2 cells from type II and III clones. Immunosuppression by antithymocyte serum globulin fraction was an effective method of preparing the syngeneic host so that cells with a low oncogenic potential would grow as tumors, whereas total body irradiation was not effective. For cells with a high oncogenic potential both ways of immunosuppression were sufficient. Admixing lethally irradiated cells in the cell inoculum slightly enhanced the tumor development from cells with low oncogenic potential and such addition was clearly effective for cells with a higher oncogenic potential, both for the antibody-treated and for the irradiated series. The findings were reproducible. The study stresses the importance of immunosuppression by antithymocyte globulins for detecting in vitro transformed weakly oncogenic cells. (author)

Radiosensitivity of defined populations of lymphocytes. VI. Functional, structural, and biochemical consequences of in vitro irradiation

International Nuclear Information System (INIS)

Anderson, R.E.; Standefer, J.C.; Scaletti, J.V.

1977-01-01

Single cell suspensions of BALB/c thymocytes (T cells) and nu/nu spleen cells (B cells) were exposed to 0, 50, and 500 rads and examined for topological abnormalities and alterations in surface glycoproteins and capacity to traffic normally upon transfer to syngeneic recipients. The results show that irradiated lymphocytes from both sources undergo extensive topological alterations which become more pronounced with the passage of time and which appear to precede the loss of cell viability. Viable T and B cells irradiated in vitro also fail to recirculate normally and accumulate in abnormal proportions in the spleen at the expense of the lymph nodes and gut-associated lymphoid tissues. Similarly, after a 2-hr incubation in saline at room temperature, irradiation of both T and B cells resulted in alterations in extractable surface glycoproteins. The results are consistent with the hypothesis that alterations in the rcirculation of irradiated lymphocytes are associated with alterations in the plasma membrane

Participation of bone marrow stromal cells in hemopoietic recovery of rats irradiated and then parabiosed with a non-irradiated litter mate, 2. Scanning and transmission electron microscopic observations

Energy Technology Data Exchange (ETDEWEB)

Kagawa, Koichi; Hayashi, Keiki; Awai, Michiyasu

1986-07-01

A light microscopical study on the recovery process after lethal irradiation and parabiosis has been made. Electron microscopically, in the bone marrow of lethally irradiated rats, hemorrhage occurred due to detachment of sinus endothelial cells. Afterwards, reticulum cells with small intracytoplasmic lipid droplets appeared. On day 3, these cells were rapidly replaced by the reticulum cells with large lipid droplets, and resulted in fatty marrow within 7 days. Spindle-shaped fibroblastoid reticulum cells were also observed. In the bone marrow of lethally irradiated rats parabiosed with non-treated litter mates, hemopoiesis was initiated by adhesion of nucleated blood cells to intricated fine cytoplasmic pseudopods of fat-storage cells. On days 3 to 5, in parallel with progressive hemopoietic recovery, fibroblastoid and reticulum cells with large lipid droplets decreased whereas those with small droplets increased. On day 8, reticulum cells with lipid droplets were seldom seen, and hemopoietic distribution became the same as normal. These results suggested that bone marrow stromal cells, namely reticulum, fat-storage, and fibroblastoid cells share a common cellular origin, and also that they regain their structure and function when fat-storage cells were placed in contact with hemopoietic precursor cells.

Cell survival following alpha particle irradiation: critical sites and implications for carcinogenesis

International Nuclear Information System (INIS)

Lloyd, E.L.; Gemmell, M.A.; Henning, C.B.; Gemmell, D.S.; Zabransky, B.J.

1976-01-01

In experiments in which mammalian cells were irradiated with 5.6 MeV alpha particles from a Tandem Van de Graaff machine we have confirmed the finding of others that the mean lethal dose (D 0 ) is about 100 rad, but by measurements of the area of the cell nuclei as irradiated we found that this mean lethal dose corresponds not to 1, as expected, but to about 27 alpha particles per cell nucleus. (The exact number appears to change slightly with cell passage number.) This allows for the possibility that the direct action of alpha particles on the nucleus may be the important event in carcinogenesis, a theory which was previously difficult to accept if a single particle hitting the nucleus anywhere was considered to be lethal. Evidence is presented to implicate the nucleolus as a possible critical site for the inhibition of reproductive integrity of the cell

Caffeine and D2O medium interact in affecting the expression of radiation-induced potentially lethal damage

International Nuclear Information System (INIS)

Utsumi, H.; Elkind, M.M.

1991-01-01

Earlier work has been extended to compare the killing of long-phase V79 Chinese hamster cells by ionizing radiation when they are treated immediately after irradiation with medium containing either caffeine or 90% D 2 O. The object was to determine if the enhanced killing due to post-treatment with caffeine, or D 2 O, resulted from action on the same sector of potentially lethal damage as appeared to be the case for hypertonic shock and D 2 O medium. The treatments by themselves were not toxic to unirradiated cells. We found that the enhanced expression of potentially lethal damage by post-treatment with caffeine or D 2 O medium is similar. For example, the kinetic of the repair of the potentially lethal damage expressible by either post-treatment was similar, and an additive enhancement of potentially lethal damage occurred when the two treatments were administered sequentially. These findings suggest that caffeine and D 2 O medium affect the same sector of potentially lethal damage. When the two treatments were combined, however, they competed with each other. Thus, although caffeine and D 2 O medium act on the same sector of potentially lethal damage they do so differently, suggesting that more than one pathway of the expression of radiation damage can result in the same phenotypic effect. (author)

Influence of immunization on serum γ-globulin levels of calves following whole-body X irradiation

International Nuclear Information System (INIS)

Koch, F.; Mehlhorn, G.; Neumeister, K.; Johannsen, U.; Panndorf, H.

1980-01-01

Calves aged 2.5 to 4 months were whole-body X irradiated with mean lethal doses between 1.2 and 1.7 Gy. The effect of different immunization procedures on the irradiation-induced reaction of the serum gamma globulin levels was studied. Immunization 14 and 21 days before irradiation resulted in obvious stimulation gamma globulin production. After parenteral antigen administration the nearly 2 weeks lasting increase of the gamma globulin level rose in the irradiated animals but declined in the sham-irradiated calves. After a lethal dosis of 1.7 Gy there was a decrease of the gamma globulins 3 weeks post irradiation, at the climax of the radiation syndrome. When 1.5 Gy were used the increase of the gamma globulin concentration was observed also after oral administration of the antigen. The response of the irradiated animals in the secondary reaction of the antibody production was most lear after boosting with homologous bacteria. The stimulating effect of the irradiation on the serum globulin levels after immunization prior to irradiation has been attributed to the reaction of the immunoglobulin-producing system to the release of tissue proteins and antigens, respectively

Intracranial AAV-IFN-β gene therapy eliminates invasive xenograft glioblastoma and improves survival in orthotopic syngeneic murine model.

Science.gov (United States)

GuhaSarkar, Dwijit; Neiswender, James; Su, Qin; Gao, Guangping; Sena-Esteves, Miguel

2017-02-01

The highly invasive property of glioblastoma (GBM) cells and genetic heterogeneity are largely responsible for tumor recurrence after the current standard-of-care treatment and thus a direct cause of death. Previously, we have shown that intracranial interferon-beta (IFN-β) gene therapy by locally administered adeno-associated viral vectors (AAV) successfully treats noninvasive orthotopic glioblastoma models. Here, we extend these findings by testing this approach in invasive human GBM xenograft and syngeneic mouse models. First, we show that a single intracranial injection of AAV encoding human IFN-β eliminates invasive human GBM8 tumors and promotes long-term survival. Next, we screened five AAV-IFN-β vectors with different promoters to drive safe expression of mouse IFN-β in the brain in the context of syngeneic GL261 tumors. Two AAV-IFN-β vectors were excluded due to safety concerns, but therapeutic studies with the other three vectors showed extensive tumor cell death, activation of microglia surrounding the tumors, and a 56% increase in median survival of the animals treated with AAV/P2-Int-mIFN-β vector. We also assessed the therapeutic effect of combining AAV-IFN-β therapy with temozolomide (TMZ). As TMZ affects DNA replication, an event that is crucial for second-strand DNA synthesis of single-stranded AAV vectors before active transcription, we tested two TMZ treatment regimens. Treatment with TMZ prior to AAV-IFN-β abrogated any benefit from the latter, while the reverse order of treatment doubled the median survival compared to controls. These studies demonstrate the therapeutic potential of intracranial AAV-IFN-β therapy in a highly migratory GBM model as well as in a syngeneic mouse model and that combination with TMZ is likely to enhance its antitumor potency. © 2016 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.

Ionizing radiation and autoimmunity: Induction of autoimmune disease in mice by high dose fractionated total lymphoid irradiation and its prevention by inoculating normal T cells

International Nuclear Information System (INIS)

Sakaguchi, N.; Sakaguchi, S.; Miyai, K.

1992-01-01

Ionizing radiation can functionally alter the immune system and break self-tolerance. High dose (42.5 Gy), fractionated (2.5 Gy 17 times) total lymphoid irradiation (TLI) on mice caused various organ-specific autoimmune diseases, such as gastritis, thyroiditis, and orchitis, depending on the radiation dosages, the extent of lymphoid irradiation, and the genetic background of the mouse strains. Radiation-induced tissue damage is not the primary cause of the autoimmune disease because irradiation of the target organs alone failed to elicit the autoimmunity and shielding of the organs from irradiation was unable to prevent it. In contrast, irradiation of both the thymus and the peripheral lymphoid organs/tissues was required for efficient induction of autoimmune disease by TLI. TLI eliminated the majority of mature thymocytes and the peripheral T cells for 1 mo, and inoculation of spleen cell, thymocyte, or bone marrow cell suspensions (prepared from syngeneic nonirradiated mice) within 2 wk after TLI effectively prevented the autoimmune development. Depletion of T cells from the inocula abrogated the preventive activity. CD4 + T cells mediated the autoimmune prevention but CD8 + T cells did not. CD4 + T cells also appeared to mediate the TLI-induced autoimmune disease because CD4 + T cells from disease-bearing TLI mice adoptively transferred the autoimmune disease to syngeneic naive mice. Taken together, these results indicate that high dose, fractionated ionizing radiation on the lymphoid organs/tissues can cause autoimmune disease by affecting the T cell immune system, rather than the target self-Ags, presumably by altering T cell-dependent control of self-reactive T cells. 62 refs., 9 figs., 2 tabs

Oscillations of serum and tissue lipids in rats X-irradiated at different times of day

International Nuclear Information System (INIS)

Ahlers, I.; Ahlersova, E.; Toropila, M.; Smajda, B.; Praslicka, M.

1983-01-01

Young male Wistar rats (mean body mass 200 g) adapted to a 12:12 h light:dark regimen (7 a.m. to 7 p.m., 7 p.m. to 7 a.m.) were X-irradiated at 3-h intervals during one day with doses of 2.39 or 14.25 Gy and were killed 48 or 24 h afterwards. Nonesterified fatty acids were determined in their serum and white and brown adipose tissue, and triacylglycerols, phospholipids and total cholesterol in their serum and liver. The reaction of serum and tissue lipids during the day varied after both non-lethal and lethal irradiation. After non-lethal exposure, most of the curves, as regards their course, the presence of rhythm and their oscillation properties, concurred with the lipid indicator curves in the control series and indicated that the organism's response is dependent on the time of day. Circadian variation of serum and adipose tissue nonesterified fatty acid levels, the liver triacylglycerol concentration and the adrenal cholesterol concentration in lethally irradiated animals showed no significant dependence on the time of application of the stimulus. An analysis of circadian variation of the effectiveness of a stimulus facilitates understanding of the organism's reactivity better than a single examination in the morning. (author)

Lethal doses of ionizing radiation versus endogenous level of superoxide dismutase

Energy Technology Data Exchange (ETDEWEB)

Lipecka, K; Domanski, T; Dniaszewska, K; Grabowska, B; Pietrowicz, D; Lindner, P; Cisowska, B; Gorski, H [Military Medical Academy, Lodz (Poland). Inst. of Occupational Medicine

1982-06-22

The stability of superoxide dismutase (SOD) as well as its activity distribution in a human population were investigated. The SOD activity level of the erythrocytes proved to be an index for the endogenous SOD activity in the whole body. In a rat population, having similar SOD frequency distribution as a human population, the mortality due to acute irradiation depended on the SOD level; after a single acute dose approximating the lethal dose (LD/sub 50/30/) the survival depended distinctly on the endogenous SOD activity level.

Glucorticoids/insulin ratio in irradiated animal blood

International Nuclear Information System (INIS)

Mizina, T.Yu.

1990-01-01

Similar changes in blood levels of immunoreactive insulin (IRI) and glucocorticoids (GC) were observed in rats, mice and dogs after X-irradiation with lethal doses. The use of the blood GC/IRI ratio indices in estimating the functional status of the exposed organism is discussed

RBE of Cf-252 neutrons as determined by its lethal, mutagenic, and cytogenetic effects on human cells

International Nuclear Information System (INIS)

Ban, Sadayuki

1989-01-01

To assess the biological effects of neutrons, a man-made spontaneously fissioning isotope, Cf-252, is useful as an experimental model to obtain basic biological data on mixed radiation of gamma-rays and neutrons. The paper describes the lethal effect of Cf-252 radiation on human skin fibroblasts, its lethal and mutagenic effect on HeLa MR cells, and the micronuclei inducing effect on human peripheral lymphocytes. Dose-survival responses of three fibroblast cell strains exposed to Cf-252 radiation are measured. Individual difference is larger than the experimental fluctuation. D 10 values of each strain are obtained from the linear model and linear-quadratic model. Though the dose rate of X-ray is higher than that of Cf-252 radiations, the mean value of RBE(n+γ) is simply obtained as 1.86+0.31 (RBE:relative biological effectiveness). RBE(n) of Cf-252 neutrons to high-dose-rate X-rays is 2.29. After X-ray irradiation, the survival curve of HeLa MR cells gives an extrapolation number of 3.6. It is 1.3 after Cf-252 irradiation. At 50% survival, RBE(n+γ) and RBE(n) are 2.05 and 2.6, respectively. At 10% survival they are 2.05 and 2.6. The mutation frequencies after X-ray irradiation showed a significant non-linear increase with dose. Those after Cf-252 irradiation increase linearly with dose. (N.K.)

Immune responsiveness and incidence of reticulum cell sarcoma in long-term syngeneic radiation chimeras

International Nuclear Information System (INIS)

Adorini, L.; Gorini, G.; Covelli, V.; Ballardin, E.; di Michele, A.; Bassani, B.; Metalli, P.; Doria, G.

1976-01-01

Long-term syngeneic radiation chimeras displayed a very low incidence of reticulum cell sarcoma as compared with control mice. Immune reactivity of these animals was studied in vivo by anti-dinitrophenyl antibody titer and affinity and in vitro by mitotic responsiveness to phytohemagglutinin, concanavalin A and lipopolysaccharide. Antibody titer and affinity as well as the response to T lectins were found to be increased in chimeras. These results were attributed to increased function of mature T2 cells, which could explain the reduced incidence of reticulum cell sarcoma in chimeras

Suicide Lethality: A Concept Analysis.

Science.gov (United States)

DeBastiani, Summer; De Santis, Joseph P

2018-02-01

Suicide is a significant health problem internationally. Those who complete suicide may have different behaviors and risk factors than those who attempt a non-fatal suicide. The purpose of this article is to analyze the concept of suicide lethality and propose a clear definition of the concept through the identification of antecedents, attributes, and consequences. A literature search for articles published in the English language between 1970 and 2016 was conducted using MEDLINE, the Cochrane Library, Pubmed, Psychlit, Ovid, PsycINFO, and Proquest. The bibliographies of all included studies were also reviewed to identify additional relevant citations. A concept analysis was conducted on the literature findings using six stages of Walker and Avant's method. The concept analysis differentiated between suicide, lethality, suicidal behavior, and suicide lethality. Presence of a suicide plan or a written suicide note was not found to be associated with the majority of completed suicides included in the definition of suicide lethality. There are a few scales that measure the lethality of a suicide attempt, but none that attempt to measure the concept of suicide lethality as described in this analysis. Clarifying the concept of suicide lethality encourages awareness of the possibility of different suicidal behaviors associated with different suicide outcomes and will inform the development of future nursing interventions. A clearer definition of the concept of suicide lethality will guide clinical practice, research, and policy development aimed at suicide prevention.

Hemostimulating efficiency of non-steroid anti-inflammatory drugs under modified irradiation conditions

International Nuclear Information System (INIS)

Zhvoronkov, L.P.; Sklobovskaya, I.Eh.

1988-01-01

Non-steroid anti-inflammatory drugs (NSAID) were found to have hemostimulating effect in mice after irradiation. This effect was rather definite under irradiation conditions modified by dose fractioning or radioprotective chemicals. NSAID application during fractionated irradiation with midlethal integral dose leads to almost complete recovery of bone marrow hemopoiesis by the 9th day of radiation illness. NSAID usage combined with chemical radioprotectors provides effective hemopoiesis stimulation leading to survival increase in animals, irradiated with absolutely lethal doses. (author)

The LDsub(50/30) and the survival time in whole-body gamma-irradiated conventional and germfree Minnesota miniature piglets

International Nuclear Information System (INIS)

Mandel, L.; Travnicek, J.; Talafantova, M.; Zahradnickova, M.

1980-01-01

The median lethal exposure causing the death in 30 days after single whole-body gamma-irradiation (the LD 50/30) was found to be 2731 MBq (73.8 mC/kg) for conventional piglets, but 3226 MBq (87.2 mC/kg) for germ-free piglets both irradiated 14 days after birth. After lethal exposures, the survival time in germ-free piglets was prolonged for 7 days in comparison with conventional piglets. (author)

1. modification of the proliferative capacity of transplanted bone marrow colony forming units by changes in the host environment

International Nuclear Information System (INIS)

Beran, M.; Tribukait, B.

1974-01-01

Regulation of the proliferation of transplanted colony forming units (CFUs) was investigated in lethally irradiated mice, pretreated by methods known to accelerate hemopoietic recovery after sublethal irradiation. Prospective recipients were exposed to either hypoxia, vinblastine or priming irradiation and at different intervals thereafter lethally irradiated and transplanted with bone marrow. Repopulation of CFUs was determined by counting the number of splenic colonies in primary recipients or by retransplantation. Regeneration of grafted CFUs was greatly accelerated and their self-renewal capacity increased in mice grafted within 2 days after hypoxia. Also the number of splenic colonies formed by grafted syngeneic CFUs as well as by C57B1 parent CFUs growing in BC3F1 hosts was significantly increased. The effect was not dependent on the seeding efficiency of CFUs and apparently resulted from hypoxia induced changes in the hosts' physiological environment. Proliferative capacity of grafted CFUs increased remarkably in hosts receiving vinblastine 2 or 4 days prior to irradiation. Priming irradiation given 6 days before main irradiation accelerated, given 2 days before impaired regeneration of CFUs. The increased rate of regeneration was not related to the cellularity of hemopoietic organs at the time of transplantation. The growth of CFUs in diffusion chambers implanted into posthypoxic mice was only slightly improved which does indicate that the accelerated regeneration of CFUs in posthypoxic mice is mainly due to the changes in the hemopoietic microenvironment. A short conditioning of transplanted CFUs by host factor(s) was sufficient to improve regeneration. The results might suggest that the speed of hemopoietic regeneration depends on the number of CFUs being induced to proliferate shortly after irradiation, rather than on the absolute numbers of CFUs available to the organism. (author)

Effect of gamma irradiation on Lasioderma serricorne (Fabricius, 1792) (Coleoptera, Anobidae)

International Nuclear Information System (INIS)

Wiendl, F.M.; Arthur, V.

1975-01-01

The results obtained when studying the effect of gamma-irradiation during the different phases of the development cycle of Lasioderma serricorne (Fabr.,1792) is presented. Lethal doses for eggs and adults, as well as hatching of adults when irradiation was applied to larvae and pupae were determined. Also determined was the fertility of adults when the pupae, or the adults themselves, were irradiated. As a result, inhibition of larval hatching was obtained with a dose of 5 krad, and a immediate lethal dose (LD(sub)I) for adults of more than 475 krad was found. Doses for larvae irradiation which resulted in non-hatching of adults were over 27 krad. 30 krad were not sufficient for pupae to inhibit hatching. 10 krad doses can be considered as sterilizing doses for pupae or adults, as the appliance of 10 krad doses to pupae resulted in only 0,217% fertility, whereas a dose of 9 krad in adults caused a progeny of only 0,25%, in comparison to the control [pt

Biological markers as predictors of radiosensitivity in syngeneic murine tumors

International Nuclear Information System (INIS)

Chang, Sei Kyung; Shin, Hyun Soo; Seong, Jin Sil; Kim, Sung Hee

2006-01-01

We investigated whether a relationship exists between tumor control dose 50 (TCD 50 ) or tumor growth delay (TGD) and radiation induced apoptosis (RIA) in syngeneic murine tumors. Also we investigated the biological markers that can predict radiosensitivity in murine tumor system through analysis of relationship between TCD 50 , TGD, RIA and constitutive expression levels of the genetic products regulating RIA. Syngeneic murine tumors such as ovarian adenocarcinoma, mammary carcinoma, squamous cell carcinoma, fibrosarcoma, hepatocarcinoma were used in this study. C3H/HeJ mice were bred and maintained in our specific pathogen free mouse colony and were 8 ∼ 12 weeks old when used for the experiments. The tumors, growing in the right hind legs of mice, were analyzed for TCD 50 , TGD, and RIA at 8 mm in diameter. The tumors were also analyzed for the constitutive expression levels of p53, p21 WAF1/CIP1 , BAX, Bcl-2, Bcl-x L , Bcl-x S , and p34. Correlation analysis was performed whether the level of RIA were correlated with TCD 50 or TGD, and the constitutive expression levels of genetic products regulating RIA were correlated with TCD 50 , TGD, RIA. The level of RIA showed a significant positive correlation (R = 0.922, ρ = 0.026) with TGD, and showed a trend to correlation (R = -0.848), marginally significant correlation with TCD 50 (ρ = 0.070). It indicates that tumors that respond to radiation with high percentage of apoptosis were more radiosensitive. The constitutive expression levels of p21 WAF1/CIP1 and p34 showed a significant correlation either with TCD 50 (R = 0.893, ρ = 0.041 and R = 0.904, ρ = 0.035) or with TGD (R = -0.922, ρ 0.026 and R = -0.890, ρ = 0.043). The tumors with high constitutive expression levels of p21 WAF1/CIP1 or p34 were less radiosensitive than those with low expression. Radiosensitivity may be predicted with the level of RIA in murine tumors. The constitutive expression levels of p21 WAF1/CIP1 or p34 can be used as biological

Biological markers as predictors of radiosensitivity in syngeneic murine tumors

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Chang, Sei Kyung; Shin, Hyun Soo [Bundang CHA General Hospital, Seongnam (Korea, Republic of); Seong, Jin Sil; Kim, Sung Hee [Yonsei Cancer Center, Yonsei University College of Medicine, Seoul (Korea, Republic of)

2006-06-15

We investigated whether a relationship exists between tumor control dose 50 (TCD{sub 50}) or tumor growth delay (TGD) and radiation induced apoptosis (RIA) in syngeneic murine tumors. Also we investigated the biological markers that can predict radiosensitivity in murine tumor system through analysis of relationship between TCD{sub 50}, TGD, RIA and constitutive expression levels of the genetic products regulating RIA. Syngeneic murine tumors such as ovarian adenocarcinoma, mammary carcinoma, squamous cell carcinoma, fibrosarcoma, hepatocarcinoma were used in this study. C3H/HeJ mice were bred and maintained in our specific pathogen free mouse colony and were 8 {approx} 12 weeks old when used for the experiments. The tumors, growing in the right hind legs of mice, were analyzed for TCD{sub 50}, TGD, and RIA at 8 mm in diameter. The tumors were also analyzed for the constitutive expression levels of p53, p21{sup WAF1/CIP1}, BAX, Bcl-2, Bcl-x{sub L}, Bcl-x{sub S}, and p34. Correlation analysis was performed whether the level of RIA were correlated with TCD{sub 50} or TGD, and the constitutive expression levels of genetic products regulating RIA were correlated with TCD{sub 50}, TGD, RIA. The level of RIA showed a significant positive correlation (R = 0.922, {rho} = 0.026) with TGD, and showed a trend to correlation (R = -0.848), marginally significant correlation with TCD{sub 50} ({rho} = 0.070). It indicates that tumors that respond to radiation with high percentage of apoptosis were more radiosensitive. The constitutive expression levels of p21{sup WAF1/CIP1} and p34 showed a significant correlation either with TCD{sub 50} (R = 0.893, {rho} = 0.041 and R = 0.904, {rho} = 0.035) or with TGD (R = -0.922, {rho} 0.026 and R = -0.890, {rho} = 0.043). The tumors with high constitutive expression levels of p21{sup WAF1/CIP1} or p34 were less radiosensitive than those with low expression. Radiosensitivity may be predicted with the level of RIA in murine tumors. The

Severe acute radiation syndrome. Treatment of a lethally 60Co-source irradiated accident victim in China with HLA-mismatched peripheral blood stem cell transplantation and mesenchymal stem cells

International Nuclear Information System (INIS)

Guo Mei; Dong Zheng; Qiao Jianhui

2014-01-01

This is a case report of a 32-year-old man exposed to a total body dose of 14.5 Gy γ-radiation in a lethal 60 Co-source irradiation accident in 2008 in China. Frequent nausea, vomiting and marked neutropenia and lymphopenia were observed from 30 min to 45 h after exposure. HLA-mismatched peripheral blood stem cell transplantation combined with infusion of mesenchymal stem cells was used at Day 7. Rapid hematopoietic recovery, stable donor engraftment and healing of radioactive skin ulceration were achieved during Days 18-36. The patient finally developed intestinal obstruction and died of multi-organ failure on Day 62, although intestinal obstruction was successfully released by emergency bowel resection. (author)

Augmentation of transfer of experimental autoimmune thyroiditis (EAT) in mice by irradiation of recipients

International Nuclear Information System (INIS)

Williams, W.V.; Kyriakos, M.; Sharp, G.C.; Braley-Mullen, H.

1987-01-01

Experimental autoimmune thyroiditis (EAT) can be adoptively transferred to normal syngeneic recipients using spleen cells from susceptible strains of mice primed in vivo with mouse thyroglobulin (MTg) and lipopolysaccharide (LPS) following in vitro activation of spleen cells by culture with MTg. Irradiation of recipient animals markedly augments the severity of thyroiditis induced in this system. Irradiation of recipients does not alter the time course of the development of thyroiditis, nor does it alter the requirement for both in vivo priming and in vitro activation of spleen cells for the development of EAT. Spleen cells from EAT-resistant strains of mice (e.g., Balb/c) do not induce EAT in irradiated recipients. Irradiated recipients develop significant levels of anti-MTg antibodies while unirradiated recipients have little detectable antibody response. The augmenting effect of irradiation can be substantially reversed by transferring naive spleen cells to recipients prior to the transfer of MTg/LPS-primed in vitro-activated spleen cells. In addition athymic CBA/Tufts nude mice develop more severe EAT than CBA/Tufts nude/+ littermates following transfer of activated CBA/J spleen cells. These data suggest that natural suppressor cells may regulate the development of EAT at the effector cell level

Caracterização da dose letal mínima por irradiação gama para Penicillium citrinum Characterization of minimum lethal dosis of gama irradiation to Penicillium citrinum

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A. N. Norberg

1993-12-01

Full Text Available O uso das radiações ionizantes na destruição de microrganismos responsáveis pela deterioração de alimentos ou causadores de infecções ou toxinfecções alimentares, constituiu-se aplicação da energia nuclear, para fins verdadeiramente pacíficos. Penicillium citrinum é um fungo produtor de micotoxinas, responsáveis por intoxicações em humanos e animais que se utilizam de alimentos contaminados. Há escassez de informações sobre a resistência do P. citrinum à irradiação gama; assim esta pesquisa objetivou determinar a dose letal por irradiação gama para esse microrganismo. Foram irradiadas 76 suspensões, contendo aproximadamente 100.000 esporos por mililitro, com doses entre 0,2 e 2,2 KGy (KiloGray, sendo os sobreviventes re-irradiados com doses até 3,0 KGy. O fungo foi totalmente destruído com dose de 2,2 KGy. P. citrinum descendentes dos sobreviventes de 2,0 KGy, quando re-irradiados também foram totalmente destruídos com dose de 2,2 KGy. Observou-se um aumento da resistência às doses mais baixas em relação ao fungo não irradiadoThe use of nuclear power through radiation for the destruction of microrganisms which cause food decay, and toxicosis, is specifically for peaceful purposes. Penicillium citrinum is a fungus which produce mycotoxins responsible for intoxication in humans and animals as a result of eating contaminated food. There is little informations on the resistance of P. citrinum to radiation. The objective of this research is to determine the lethal dose of gama radiation for these microrganisms. Seventy six suspensions containing approximately 100,000 spores/ml received a dose of radiation between 0.2 and 2.2 KGy (KiloGray, being one sample still alive re-irradiated with doses up to 3.0 KGy. The fungus were totally destroyed with a 2.2 KGy. Seventy six suspensions containing approximately 100,000 spores/ml received a dose of radiation between 0.2 and 2.2 KGy, being one sample still alive re-irradiated

Genetic constraints in the induction of the immune response to Ehrlich ascites tumor in mice

International Nuclear Information System (INIS)

Marusic, M.; Perkins, E.H.

1981-01-01

A single injection of irradiated Ehrlich ascites tumor (EAT) cells induces immunity in normal mice but fails to do so in T-cell-deficient-thymectomized, lethally irradiated, bone marrow-reconstituted (TIR) mice. TIR mice injected with normal syngeneic T cells develop an immune response to EAT when injected with irradiated EAT cells and reject a subsequent tumor cell challenge. In the present studies allogeneic T cells were unable to protect against EAT in TIR recipients even if harvested from donors tolerant to the recipient's transplantation antigens and injected into the TIR mice tolerant to the transplantation antigens of the injected T cells. Tolerance was produced by establishing long-term radiation chimeras of the P → F 1 type. Semiallogeneic T cells also failed to afford protection against EAT in TIR recipients. Whereas tolerance to other parental-strain transplantation antigens did not reverse the inability of parental T cells (cells from P → F 1 chimeric donors) to protect against EAT in F 1 TIR mice, it did enable F 1 T cells to afford protection in P → F 1 TIR mice

Relationship between lung colony and in situ assays

International Nuclear Information System (INIS)

Ando, K.; Koike, S.

1985-01-01

The relationship between different assays: tumor control, tumor growth delay and lung colony formation was examined after fast neutron and γ ray irradiations. Fibrosarcomas (NFSa) in syngeneic C3Hf mice were irradiated locally with 60 Co γ rays, fast neutrons or mixed beams (γ rays and fast neutrons). A comparison between the lung colony assay and the TRT 50 (50% tumor growth delay time) assay when cells were exposed to single doses of fast neutrons or γ rays, resulted in identical growth delay times. The fraction of cells surviving a single dose of fast neutrons, was 10 times higher than the surviving fraction of cells after a single dose of γ rays. Both doses resulted in the same tumor control probability (TCD 50 assay). Neither repair of potentially lethal damage nor tumor bed effect was sufficient to explain the difference between cell survival and tumor control probability. The surviving fraction of cells following fractionated irradiations of γ rays and fast neutrons were identical at 50% tumor control probabilities

Effect of a non lethal whole-body gamma irradiation on the spontaneous and evoked electroencephalographic activities of the adult rabbit

International Nuclear Information System (INIS)

Court, L.

1969-01-01

The whole of the experimental methods described (animal preparation, achievement of a precise physiological technique, dosimetry, biological information processing) allowed us to follow the changes for 15 days in the spontaneous and evoked electroencephalogram activities of rabbits submitted to a non-lethal 400 rads whole-body gamma-irradiation. Behavioural troubles, changes in the arousal state and the spontaneous electrical activity of the neo-cortex and hippocampus were noticed constantly together with an enhanced cortical excitability, and the appearance of elements of the paroxystic series sometimes in contrast with a general decrease in amplitude. After a visual stimulus the general morphology of evoked activities at the level of the primary visual areas and hippocampus was unchanged, but enhanced latencies and delays, less systematic modifications in amplitudes seemed to show out a direct effect of radiations on the nervous system and sensorial activities; these troubles seemed to occur independently from the basic electrical activity. As a whole, the changes observed were usually transitory and varied with each individual. Finally an assumption is made to explain the mechanism of arousal troubles and the general evolution of spontaneous electrical activity in the brain. (author) [fr

Restoring efficiency of hemopoietic cell transplantation in a mouse lethally irradiated by a total exposure to X rays; L'efficacite restauratrice de la greffe de cellules hemopoietiques chez la souris letalement irradiee par une exposition totale aux rayons X

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Doria, Gino

1959-10-15

This research thesis reports the study of possibility of treatments (or restoration) of a mouse which has been submitted to a lethal dose of X rays. More particularly, the author compared the restoring efficiency of bone marrow and fetal liver injected in a mouse which had been lethally irradiated by a total exposure to X rays. He also studied the functional status of the hemopoietic graft, and the emergence of the secondary disease in mice which had been as well lethally irradiated and then restored by injection of bone marrow and fetal liver. The author then addressed the influence of the induction of immune tolerance of the host with respect to the donor on the survival of a mouse lethally irradiated and restored by homologue bone marrow [French] Des resultats des recherches que nous avons conduites permettent, dans les limites de nos conditions experimentales, d'eclaircir certains aspects du probleme de la restauration des animaux irradies par la greffe de cellules hemopoietiques. On peut admettre que la moelle osseuse de 30 jours est 2 fois plus efficace que le foie foetal de 16 jours, pour ce qui concerne la survie 30 jours; ceci aussi bien en cas de restauration isologue que homologue. En outre, le foie foetal de 16 jours permet une survie d'environ 50 pc plus elevee que les foies foetaux de 13 ou 19 jours; ceci en cas de restauration isologue. On a aussi montre que les degres de capacite restauratrice des differents tissus hemopoietiques dependent du nombre de cellules souches, progenitrices des granulocytes polynucleaires. Nous avons mis en evidence, en cas de restauration par la moelle osseuse homologue, que la presence d'un greffon hemopoietique fonctionnel est necessaire et suffisante pour l'apparition de la maladie secondaire et que celle-ci est une cause suffisante et non necessaire de la mortalite tardive. La constatation experimentale que la viabilite du greffon est une cause suffisante et non necessaire de la mortalite tardive en est la preuve

Caffeine and D sub 2 O medium interact in affecting the expression of radiation-induced potentially lethal damage

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Utsumi, H. (Kyoto Univ. (Japan). Radiation Biology Center); Elkind, M.M. (Colorado State Univ., Fort Collins, CO (United States). Dept. of Radiological Health Sciences)

1991-10-01

Earlier work has been extended to compare the killing of long-phase V79 Chinese hamster cells by ionizing radiation when they are treated immediately after irradiation with medium containing either caffeine or 90% D{sub 2}O. The object was to determine if the enhanced killing due to post-treatment with caffeine, or D{sub 2}O, resulted from action on the same sector of potentially lethal damage as appeared to be the case for hypertonic shock and D{sub 2}O medium. The treatments by themselves were not toxic to unirradiated cells. We found that the enhanced expression of potentially lethal damage by post-treatment with caffeine or D{sub 2}O medium is similar. For example, the kinetic of the repair of the potentially lethal damage expressible by either post-treatment was similar, and an additive enhancement of potentially lethal damage occurred when the two treatments were administered sequentially. These findings suggest that caffeine and D{sub 2}O medium affect the same sector of potentially lethal damage. When the two treatments were combined, however, they competed with each other. Thus, although caffeine and D{sub 2}O medium act on the same sector of potentially lethal damage they do so differently, suggesting that more than one pathway of the expression of radiation damage can result in the same phenotypic effect. (author).

Wholesomeness study of irradiated salted and dried mackerel in rats

International Nuclear Information System (INIS)

Anukarahanonta, T.; Temcharoen, P.; Nagara, B.N.; Chudhabuddhi, C.; Bhamarapravati, N.

1981-01-01

A long-term multigeneration study was performed of the wholesomeness of irradiated salted and dried mackerel fed to the rats of Wistar strain and revealed no significant evidence that would impose a hazard attributable to irradiation with respect to the longevity, carcinogenecity, teratogenicity, dominant lethal, reproductive function and biophysiological function. Some abnormalities that were noted could be explained on the basis of differences in food quality due to the addition of fish protein and minerals rather than the irradiation effect

Effects of neutron-gamma or gamma irradiations on plasma clotting factors. Effect of a treatment by substituted factors

International Nuclear Information System (INIS)

Mestries, J.C.; Martin, S.; Janodet, D.; Herodin, F.; Gourmelon, P.; Fatome, M.

1991-01-01

Neutron-gamma irradiation of the baboon at lethal dose altered the plasma clotting factors and induced a fibrinoformation alteration which occurred shortly before death. These disturbances, which were not found after gamma irradiation, could explain the importance of the haemorrhagic syndrome. Treatment by P.P.S.B. (factors II, VII, X and IX) counteracted the alterations of the plasma clotting factors, but had no influence on the lethality nor on the fibrinoformation alteration which seems to be an important cause of death [fr

The influence of continuous γ-irradiation at decreasing dose-rate on the survival rote and induction of gene mutations in cultured Chinese hamster cells

International Nuclear Information System (INIS)

Feoktistova, T.P.; Elisova, E.V.; Stavrakova, N.M.

1991-01-01

Continuous γ-irradiation at decreasing dose-rate was shown to be less effective than acute exposure with regard to the lethal effect and frequency of mutations of resistance to 6-thioguanine in cultured Chinese hamster cells. The cell population subjected to continuons irradiation was d more radioresistant than the intact one. Lethal and genetic effects of continuous irradiation at decreasing dose-rate were mainly determined by the contribution of the radiation dose received during the first 24 h of exposure

The effect of thymus cells on bone marrow transplants into sublethally irradiated mice

International Nuclear Information System (INIS)

Kruszewski, J.A.; Szcylik, C.; Wiktor-Jedrzejczak, W.

1984-01-01

Bone marrow cells formed similar numbers of 10-days spleen colonies in sublethally (6 Gy) irradiated C57B1/6 mice as in lethally (7.5 Gy) irradiated mice i.e. approximately 20 per 10 5 cells. Numbers of 10 day endogenous spleen colonies in sublethally irradiated mice (0.2 to 0.6 per spleen) did not differ significantly from the numbers in lethally irradiated mice. Yet, transplants of 10 7 coisogenic marrow cells into sublethally irradiated mice resulted in predominantly endogenous recovery of granulocyte system as evidenced by utilization of ''beige'' marker for transplanted cells. Nevertheless, transplanted cells engrafted into sublethally irradiated mice were present in their hemopoietic tissues throughout the observation period of 2 months never exceeding 5 to 10% of cells. Thymus cells stimulated endogenous and exogenous spleen colony formation as well as endogenous granulopoietic recovery. Additionally, they increased both the frequency and absolute numbers of graft-derived granulocytic cells in hemopoietic organs of transplanted mice. They failed, however, to essentially change the quantitative relationships between endogenous and exogenous hemopoietic recovery. These results may suggest that spleen colony studies are not suitable for prediction of events following bone marrow transplant into sublethally irradiated mice. Simultaneously, they have strengthened the necessity for appropriate conditioning of recipients of marrow transplants. (orig.) [de

'Motheaten': a single gene model for stem cell dysfunction and early onset autoimmunity

International Nuclear Information System (INIS)

Shultz, L.D.; Zurier, R.B.

1978-01-01

Mice homozygous for the recessive mutation called 'motheaten' (me) develop autoantibodies against thymocytes and double stranded DNA by three weeks of age. Sera from littermate control mice were consistently negative for these autoantibodies. The thymocytotoxic autoantibody was an IgM immunoglobulin as determined by its sensitivity to 2-mercaptoethanol. This autoantibody selectively killed immature thymocytes and reacted equally well against thymocytes of all strains tested regardless of H-2 haplotype, Thy-1 or TLA specificity. Lymphoid cells from spleen, lymph node, Peyer's patch and peripheral blood were not sensitive to killing by motheaten serum. Motheaten mice appear to have increased numbers of stem cells as determined by the spleen colony assay. However, bone marrow from this mutant does not save lethally irradiated syngeneic recipients. Sublethally-irradiated subgeneic recipients of motheaten bone marrow develop hyperimmunoglobulinemia and antinuclear antibodies. Transfer of bone marrow from motheaten mice into congenitally anemic W/Wsup(v) recipients resulted in a cure of the anemia and the development of hyperimmunoglobulinemia and autoimmunity. (Auth.)

Studies on the transfer of protective immunity with lymphoid cells from mice immune to malaria sporozoites

International Nuclear Information System (INIS)

Verhave, J.P.; Strickland, G.T.; Jaffe, H.A.; Ahmed, A.

1978-01-01

In an effort to understand the mechanisms involved in the protective immunity to malarial sporozoites, an A/J mouse/Plasmodium berghei model was studied. Protective immunity could consistently be adoptively transferred only by using sublethal irradiation of recipients (500 R); a spleen equivalent (100 x 10 6 ) of donor cells from immune syngeneic mice; and a small booster immunization (1 x 10 4 ) of recipients with irradiation-attenuated sporozoites. Recipient animals treated in this manner were protected from lethal challenge with 1 x 10 4 nonattenuated sporozoites. Immune and nonimmune serum and spleen cells from nonimmune animals did not protect recipient mice. Fewer immune spleen cells (50 x 10 6 ) protected some recipients. In vitro treatment of immune spleen cells with anti-theta sera and complement abolished their ability to transfer protection. This preliminary study suggests that protective sporozoite immunity can be transferred with cells, and that it is T cell dependent

Stem-Cell Inactivation on Transplantation of Haemopoietic Cell Suspensions from Genetically Different Donors

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Petrov, R. V. [Institute of Biophysics, Ministry of Public Health of the USSR, Moscow, USSR (Russian Federation)

1969-07-15

The transplantation of a mixture of haemopoietic or lymphoid cells from two genetically different mice into lethally irradiated F{sub 1} recipients results in marked or total inactivation of the colony-forming units of the graft. This phenomenon is observed following transplantation of mixtures of spleen cells or bone-marrow cells from animals of different genotypes: CBA + C57BL, A + CBA, A + C57BL, C3H + C57BL, CBA + (CBA x C57BL) F{sub 1}. Maximum inactivation is observed when lymph-node cells of one genotype are transplanted with spleen or bone-marrow cells of another genotype. Use of non-syngenic kidney cells or lymphoid cells inactivated by irradiation as one component of the mixture shows that inactivation of genetically heterogeneous stem cells requires the participation of viable lymphoid cells. The inactivation phenomenon is also observed with Jerne's method. This shows that inactivation affects not only colony-forming cells but also the immunologically competent precursors of antibody-producing cells. (author)

Enhancement of the far-UV lethality in yeast Candida guilliermondii by near-UV post-irradiation

International Nuclear Information System (INIS)

Fraikin, G.Y.; Pospelov, M.E.; Rubin, L.B.

1980-01-01

In experiments with the non-photoreactivable yeast Candida guilliermondii, radiations at 313, 334 and 365 nm, having no effect on untreated cell populations, produced an 'enhancing' effect on the lethality of 254 nm-pretreated cells. Wavelengths in the visible region of the spectrum did not exhibit a similar effect. (author)

Proliferative compensation of residual radiation damage in the compartment of hematopoietic early progenitor cells of the mouse

International Nuclear Information System (INIS)

Huebner, G.E.; Wangenheim, K.H. von; Feinendegen, L.E.

1984-01-01

The rate of cell entry from the compartment of hematopoietic early progenitor cells into differentiation was determined in sublethally irradiated mice. By use of the criterion of repopulating ability, transplantation of 5-( 125 I) iodo-2'-deoxyuridine labeled bone marrow cells into fatally irradiated syngeneic recipients allows to measure the relative number of early progenitor cells lodging in the spleen and the turnover of these cells in the donors. Following 450 rad the relative number of transplantable early progenitor cells in S-phase recovers to normal within 2 weeks and stabilizes after 5 weeks. At this time, the labeled progenitors turn over with a half-time of 1.4-2.2 days; the respective times for unirradiated mice are 1.5-1.8 days. This, quantitative and qualitative residual radiation damage that is known to exist in the compartment of CFU-S, is disguised within 2-5 weeks after irradiation by proliferative compensation in the entirety of early hemopoietic precursor cells which are here defined by their capacity of selfrenewal and delivery of differentiated cells and of seeding to spleens of lethally irradiated recipients. (orig.)

Cell surface antigens of radiation leukemia virus-induced BALB/c leukemias defined by syngeneic cytotoxic T lymphocytes

International Nuclear Information System (INIS)

Kaneko, Yukio; Oettgen, H.F.; Obata, Yuichi; Nakayama, Eiichi.

1989-01-01

Two cell surface antigens of mouse leukemias were defined by BALB/c cytotoxic T lymphocytes (CTL) generated against syngeneic radiation leukemia virus (RadLV)-induced leukemia, BALBRV1 or BALBRVD. Hyperimmunization of BALB/c mice with irradiated leukemias followed by in vitro sensitization of primed spleen cells resulted in the generation of CTL with high killing activity. The specificity of CTL was examined by direct cytotoxicity assays and competitive inhibition assays. A shared cell surface antigen, designated as BALBRV1 antigen, was detected by BALB/c anti-BALBRV1 CTL. BALBRV1 antigen was expressed not only on RadLV-induced BALB/c leukemias except for BALBRVD, but also on spontaneous or X-ray-induced BALB/c leukemias, chemically-induced leukemias with the H-2 d haplotype and some chemically-induced BALB/c sarcomas. In contrast, a unique cell surface antigen, designated as BALBRVD antigen, was detected by BALB/c anti-BALBRVD CTL. BALBRVD antigen was expressed only on BALBRVD, but not on thirty-nine normal lymphoid or tumor cells. These two antigens could be distinguished from those previously defined on Friend, Moloney, Rauscher or Gross murine leukemia virus (MuLV) leukemias, or MuLV-related antigens. Both cytotoxic responses were blocked by antisera against H-2K d , but not H-2D d . The relationship of BALBRV1 antigen and BALBRVD antigen to endogenous MuLV is discussed with regard to the antigenic distribution on tumor cell lines. (author)

Clonal deletion: A mechanism of tolerance in mixed bone marrow chimeras

International Nuclear Information System (INIS)

Yu, J.C.; Webster, M.; Fox, I.J.

1990-01-01

The mechanism of antigen-specific immunologic unresponsiveness which results from lethal irradiation and mixed (syngeneic-allogeneic) bone marrow cell (BMC) reconstitution is unknown. To determine whether clonal deletion is the mechanism of tolerance in this model, monoclonal antibody (Mab) RR-4-4, specific for a T-cell receptor (V beta 6) reactive against the minor alloantigen MLsa, was employed. Six-week-old B10 mice (H-2b, Mlsb, Thyl.2) were tolerized to AKR antigens (H-2k, Mlsa, Thyl.1) by whole body irradiation (950 R) and iv infusion of T-cell-depleted (TCD) B10 BMC + non-TCD AKR BMC. Chimerism and antigen-specific tolerance were documented by flow microfluorometry (FMF), skin grafting, mixed lymphocyte reaction, and cell-mediated lympholysis. When tolerant B10 mice (n = 15) had accepted AKR skin grafts for greater than 100 days, these animals were studied for the presence of host V beta 6+ T cells using Mab RR-4-4. FMF revealed that 0-5% of host (B10) lymph node and spleen cells from chimeras were V beta 6+ while 15-20% of lymph node and spleen cells from control B10 mice expressed V beta 6. These data demonstrate that clonal deletion occurs in the lethal irradiation-mixed reconstitution model as evidenced by the near total elimination of Mlsa-reactive V beta 6+ T cells and suggest that it maybe a mechanism responsible for tolerance in adult mice

Preliminary studies on factors controlling the rate of regrowth of heavily x-irradiated rat rhabdomyosarcoma tumors

International Nuclear Information System (INIS)

Tenforde, T.S.; Curtis, S.B.; Woodruff, H.K.; Parks, D.L.; Daniels, S.J.; Crabtree, K.E.; Schilling, W.A.; DeGuzman, R.J.

1977-12-01

Following large single doses of x rays, rat rhabdomyosarcoma tumors exhibit a volume response which characteristically has a swelling phase, a regression phase, a rapid ''initial'' regrowth phase and a slow ''late'' regrowth phase. The preliminary experiments reported here were designed to examine three mechanisms that may underlie the reduction in growth rate occurring in the late regrowth phase; heritable non-lethal cellular damage, host immunity, delayed post-irradiation tissue and vascular damage. Based on retransplantation experiments and studies with immunosuppressed rats, neither heritable non-lethal damage nor host immune factors appear to influence the regrowth rate of tumors receiving radiation doses well below the cure level. After an x-ray dose approaching the cure level, regrowing tumors were observed to have a greatly reduced growth rate, possibly reflecting the presence of heritable non-lethal damage and/or an increased antigenicity of the heavily irradiated tumor cells. Morphometric analysis of histological sections did not reveal statistically significant abnormalities at the cellular level during the late regrowth phase, except for an increase in the percentage of necrotic tissue relative to non-irradiated tumors. The morphological resolution of small blood vessels was not adequate to evaluate delayed vascular damage in regrowing irradiated tumors

Estimation of the contribution of ionization and excitation to the lethal effect of ionizing radiation

International Nuclear Information System (INIS)

Petin, V.G.; Komarov, V.P.

1982-01-01

A simple theoretical model is proposed for estimating the differential contribution of ionization and excitation to the lethal effect of ionizing radiation. Numerical results were obtained on the basis of published experimental data on the ability of bacterial cells Escherichia coli to undergo photoreactivation of radiation-induced damage. It was shown that inactivation by excitation may be highly significant for UV-hypersensitive cells capable of photoreactivation; inactivation by excitation increased with the energy of ionizing radiation and the volume of irradiated suspensions. The data are in qualitative agreement with the assumption of a possible contribution of the UV-component of Cerenkov radiation to the formation of excitations responsible for the lethal effect and the phenomenon of photoreactivation after ionizing radiation. Some predictions from the model are discussed. (orig.)

Studies on the regeneration of the CFU-C population in blood and bone marrow or lethally irradiated dogs after autologous transfusion of cryopreserved mononuclear blood cells

International Nuclear Information System (INIS)

Nothdurft, W.; Bruch, C.; Fliedner, T.M.; Rueber, E.

1977-01-01

In a group of 8 lethally irradiated (1200 R) dogs, that were transfused autologously with cryopreserved mononuclear cells (MNC) derived from the peripheral blood by leucapheresis the concentration of colony-forming units in agar (CFU-C) in bone marrow and peripheral blood was estimated at regular intervals after irradiation and transfusion of MNC. The numbers of MNC transfused per kg body weight ranged from 0.32 x 10 9 to 1.63 x 10 9 with an incidence of CFU-C between 0.02 x 10 5 and 1.38 x 10 5 . In 6 dogs the CFU-C levels in the bone marrow reached the normal preirradiation values between days 15 and 20. But in 2 dogs that had received the lowest CFU-C numbers the regeneration of the bone marrow CFU-C was markedly delayed. In general the time course of the bone marrow repopulation by CFU-C for single dogs was reflected by a corresponding regeneration pattern of the blood CFU-C. The time course of the curves for the blood CFU-C levels on the other hand was of the same kind as for the granulocyte values in the peripheral blood, that reached the normal levels mainly around day 30 and thereafter. Considerable fluctuations were seen in the blood CFU-C levels of single dogs before irradiation and after mononuclear leucocyte transfusion. Despite of such limitations the blood CFU-C content appeared to be a useful indicator of haematopoietic regeneration of the bone marrow. (author)

Evaluation of lethal effect of microwave exposure on protoscolices of hydatid cyst in vitro

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Zahra Eslamirad

2015-10-01

Full Text Available Objective: To investigate the lethal effect of microwave radiation on protoscolices of hydatid cyst. Methods: The protoscolices were divided in two separate groups. The first group received continuous irradiation while the second group received repetitive irradiation. According to the exposure time, the first and the second groups were divided into 8 subgroups. Non-treated protoscolices were considered as the control in each experiment. The protoscolex mortality rate was calculated, and changes in temperature difference in protoscolex suspension before and after the irradiation and the mortality rate with the increase of exposure time were recorded. Results: The results showed that microwave was able to increase the mortality rate of protoscolices in hydatid cyst. The mortality rate from 20% in 20 s of continuous exposure was increased to 100% in 50 s. Also, the differences between the mortality rates in subgroups of the first and the second groups and the control were significant (P < 0.001. Although the effect of temperature change in repetitive irradiation was not significant, non-thermal repetitive irradiation effects were obviously stronger than the thermal continuous irradiation effects. Conclusions: It seems that, microwaves especially in the repetitive mode, may be used as a supplementary measure for both treatment and prevention of hydatidosis.

Effects of β-arabinofuranosyladenine on the growth and repair of potentially lethal damage in Ehrlich ascites tumor cells

International Nuclear Information System (INIS)

Iliakis, G.

1980-01-01

β-D-Arabinofuranosyladenine (β-araA) inhibit the growth of Ehrlich ascites tumor cells by selective inhibition of DNA polymerases. RNA and protein synthesis are not significantly affected. Addition of β-araA to the cells after irradiation resulted in a concentration-dependent decrease in survival, presumably due to the inhibition of the repair of potentially lethal damage. Since β-araA selectively inhibits DNA polymerases it is suggested that repair of potentially lethal damage involves steps at the DNA level which require some polymerization. These repair steps take place in the DNA with a velocity comparable to that of the repair of potentially lethal damage. The inhibition of the repair of potentially lethal damage by β-araA was modified by the addition of deoxyadenosine; this supports the finding that β-araA acts competitively against dATP at the molecular level. The inhibition of the repair of potentially lethal damage by β-araA, which is partly reversible, resulted in a concentration-dependent modification of the survival curve. At low concentrations of β-araA a dose-modifying decrease in survival was observed. At higher concentrations (more than 12 μM) the decrease in survival resulted in a decrease of the shoulder width of the survival curve. Eventually an exponential curve was obtained. We suggest therefore that the shoulder of the survival curve results from some repair or potentially lethal damage. Preliminary information has been obtained on the time course of this repair

Enhanced lethal effect of combined ACNU with x-ray on cultured HeLaS3 cells

International Nuclear Information System (INIS)

Kanazawa, Haruyuki; Miyamoto, Tadaaki

1983-01-01

The combined effects of ACNU and X-irradiation on cultured HeLaS 3 cells were investigated. Pretreatment with either ACNU or X-ray induced a substantial reduction in shoulder width the D 0 value of the dose-response curve for the other agent, given later was unchanged. ACNU did not inhibit the recovery of sublethal damage (SLD) induced by X-ray when this treatment preceded the spilit-dose experiment. Our results indicate that some cell damage induced by each agent is transmissible to the progeny of the surviving cells and that the interaction of ACNU and X-irradiation was lethal to the cells. (author)

Caffeine-induced hematological changes after whole-body irradiation in rat

Energy Technology Data Exchange (ETDEWEB)

Kim, Jin Kyu [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Kim, Ji Hyang; Yoon Yong Dal [Hanyang University, Seoul (Korea, Republic of)

2004-07-01

Recent research indicated dietary antioxidants were useful radioprotectors to protect organisms against radiation-induced tissue lethality and other deleterious effects. Radioprotective effects of vitamin C have been demonstrated in certain cells and animals, which would result from scavenging free radicals. Moreover, the previous studies indicated that caffeine had been shown to potently act the radioprotector in irradiated mice. However it is not clear exactly about effects of caffeine treatments chronically after irradiation. So the present studies were designed to identify the hematological effect of caffeine treatments chronically one month after whole-body gamma irradiation.

Heritable non-lethal damage to cultured human cells irradiated with heavy ions

International Nuclear Information System (INIS)

Walker, J.T.; Walker, O.A.

2002-01-01

During interplanetary flights the nuclei of all of a crew member's cells could be traversed by at least one high-LET (linear energy transfer) cosmic-ray particle. In mammalian cells irradiated in vitro about 1 in 10,000 of the surviving cells traversed by heavy particles is transformed to malignancy or mutated. What, if anything, happens to the remaining >99% of surviving cells? A retrospective analysis of archived data and samples from heavy-ion irradiation experiments with cultured human cells in vitro indicated that heavy ions caused a dose- and LET-dependent reduction in growth rates of progeny of irradiated cells, based on colony-size distributions. The maximum action cross section for this effect is between 100 and 300 μm 2 , at least as large as the cell nuclear area and up to 3 times the cross section for cell killing. Thus, heritable slow growth is the most prevalent effect of high-LET radiations on cultured animal cells, which may have implications for crew health during deep space travel. (author)

Lack of immunoglobulin M suppression by immunoglobulin G antibody in thymectomized, irradiated, and bone marrow-reconstituted mice infected with Toxoplasma gondii.

OpenAIRE

Aryanpour, J; Hafizi, A; Modabber, F

1980-01-01

Thymectomized, irradiated, bone marrow-reconstituted (T-deprived) mie infected with an avirulent strain of Toxoplasma gondii produced antibody titers comparable to those produced in intact syngeneic mice. Both immunoglobulin M (IgM) and IgG antibodies were produced in T-deprived animals; however, the IgM antibody remained constant in the presence of increasing amounts of IgG. In the intact animals, IgM became undetectable by day 50 postinfection as expected. Feedback inhibition of IgM by IgG ...

The effect of postirradiation holding at 22 degrees C on the repair of sublethal, potentially lethal and potentially neoplastic transforming damage in gamma-irradiated HeLa x skin fibroblast human hybrid cells

International Nuclear Information System (INIS)

Redpath, J.L.; Antoniono, R.J.; Mendonca, M.S.; Sun, C.

1994-01-01

The effect of postirradiation holding at 22 degrees C on cell growth, progression of cells through the cell cycle, and the repair of sublethal, potentially lethal and potentially neoplastic transforming damage in γ-irradiated HeLa x skin fibroblast human hybrid cells has been examined. Cell growth and cell cycle progression were essentially stopped at this reduced temperature. Cell survival was dramatically reduced by holding confluent cultures for 6 h at 22 degrees C, as opposed to 37 degrees C, after 7.5 Gy γ radiation delivered at a rate of 2 Gy/min. Return of the cells to 37 degrees C for 6 h after holding at 22 degrees C did not result in increased survival. A similar effect was obtained when the cells were held at 22 degrees C between split-dose irradiation of log-phase cultures where no increase in survival was observed over a split-dose interval of 4 h. In this case a partial increase in survival was observed upon returning the cells to 37 degrees C for 3 h after holding at 22 degrees C for the first 3 h of the split-dose interval. Neoplastic transformation frequency was not enhanced by holding confluent cultures for 6 h at 22 degrees C after 7.5 Gy γ radiation. This is consistent with previous observations that misrepair of potentially neoplastic transforming damage already occurs at 37 degrees C. The overall results are interpreted in terms of the reduced temperature favoring misrepair, rather than inhibition of repair, of sublethal, potentially lethal and potentially transforming radiation damage. 24 refs., 5 figs., 3 tabs

Effect of NaN3 on oxygen-dependent lethality of UV-A in Escherichia coli mutants lacking active oxygen-defence and DNA-repair systems

International Nuclear Information System (INIS)

Yamada, Kazumasa; Ono, Tetsuyoshi; Nishioka, Hajime

1996-01-01

Escherichia coli mutants which lack defence systems against such active oxygen forms as OxyR (ΔoxyR), superoxide dismutase (SOD) (sodA and sodB) and catalase (katE and katG) are sensitive to UV-A lethality under aerobic conditions, whereas OxyR- and SOD-mutants have resistance under anaerobic conditions and in the presence of sodium azide (NaN 3 ) during irradiation. UV-A induces lipid peroxidation in the ΔoxyR mutant, which is suppressed by NaN 3 . These results suggest that UV-A generates 1 O 2 or the hydroxyl radical to produce lipid peroxides intracellularly in the ΔoxyR mutant and that O 2 - stress may be generated in the sodAB mutant after 8 hr of exposure to UV-A. The sensitivities of such DNA repair-deficient mutants as recA ind- and uvrA to UV-A also were examined and compared. These mutants are sensitive to UV-A lethality under aerobic conditions but show only slight resistance under anaerobic conditions or in the presence of NaN 3 during irradiation. We conclude that NaN 3 protects these mutant cells from oxygen-dependent UV-A lethality. (author)

Repair of potentially lethal radiation damage: comparison of neutron and x-ray RBE and implications for radiation therapy

International Nuclear Information System (INIS)

Hall, E.J.; Kraljevic, U.

1976-01-01

Experiments with Chinese hamster cells have shown that neutron irradiation does not result in repair of potentially lethal damage (PLD), i.e., that which can be influenced by changes in environmental conditions following irradiation. Since PLD is presumed to be repaired in tumors but not in normal tissues, this absence of differential sparing of tumor cells relative to normal tissues--a feature characteristic of irradiation with x rays--represents an advantage of neutrons in addition to their reduced oxygen effect. At a given dose, the difference in relative biological effectiveness (RBE) between tumors and normal tissues corresponds to a 5 percent increase in tumor dose with no concomitant increase in dose to normal tissues, which could be significant in cancer therapy

Natural killer activity and suppressor cells in irradiated mice repopulated with a mixture of cells from normal and 89Sr-treated donors

International Nuclear Information System (INIS)

Levy, E.M.; Kumar, V.; Bennett, M.

1981-01-01

Mice that have been injected with 89 Sr have fairly normal B and T cell function, but are abnormal in that they lack natural killer (NK) activity and other functions that require an intact bone marrow. These mice also have an increased potential for suppressor cell activity. We had previously shown that spleen cells from 89 Sr-treated mice could transfer low NK activity and increased suppressor cell function to lethally irradiated syngeneic recipients. To investigate the mechanisms involved in perpetuating these defects, groups of normal spleen or bone marrow cells. Recipients were assayed for their NK activity and suppressor cell function 5 to 14 wk later. it was found that the addition of normal cells in the donor inoculum resulted in normal NK activity. This indicates that low NK activity in 89 Sr-treated mice was not due to the presence of a suppressor cell that prevented NK cell generation. It was additionally found that low NK activity in recipient mice could be boosted by interferon inducers. This would indicate that NK activity in the recipients was not due to a lack of interferon-sensitive pre-NK cells. Suppressor cell function in recipient mice depended on the type and number of normal cells in the donor inoculum. Bone marrow cells were very efficient in overcoming the tendency to produce suppressor cells. It took approximately 20 times more normal spleen cells to produce the same results. The implications of these findings are discussed

Wholesomeness studies of irradiated salted and dried mackerel, using rats. Part of a coordinated programme on the wholesomeness of the process of food irradiation

International Nuclear Information System (INIS)

Anukarahanonta, T.

1978-04-01

Chronic toxicity of irradiated salted and dried mackerel was evaluated by multi-generation rat feeding studies. Salted and dried mackerel samples were irradiated with 200krad, ground and mixed with a standard laboratory animal diet at 28% w/w. Wistar strain rats were used in the experiment and were divided into 3 groups and fed their respective diets, i.e. stock ration, diet containing 28% of non-irradiated salted and dried mackerel and diet containing 28% of irradiated salted and dried mackerel. The test was carried out for 3 generations. The results revealed no significant difference that would impose a hazard attributable to consumption of irradiated salted and dried mackerel with respect to longevity, carcinogenicity, teratogenicity, dominant lethal, reproductive function and biophysiological function in animals tested

Influence of whole-body irradiation on calcium and phosphate homeostasis in the rat

International Nuclear Information System (INIS)

Pento, J.T.; Kenny, A.D.

1975-01-01

Previous irradiation studies have revealed marked alterations in calcium metabolism. Moreover, the maintenance of calcium homeostasis with parathyroid hormone or calcium salts has been reported to reduce radiation lethality. Therefore, the present study was designed to evaluate the influence of irradiation on calcium homeostasis in the rat. Nine hundred rad of whole-body irradiation produced a significant depression of both plasma calcium and phosphate at 4 days postirradiation. This effect of irradiation was observed to be dose-dependent over a range of 600 to 1200 rad, and possibly related to irradiation-induced anorexia. The physiological significance of these observations is discussed

Physiological alterations in UV-irradiated cells: liquid holding recovery

International Nuclear Information System (INIS)

Aragao, B.R.

1980-01-01

The biochemical and physiological alterations that occur in ultraviolet irradiated cells, during liquid holding have been studied. Incubation in buffer acts not to interfer directly with the mechanic repairs but by promoting metabolic alterations that would block some irreversible and lethal physiological responses. (L.M.J.) [pt

Induction of tolerance to topically applied INCB using TNP-conjugated ultraviolet light-irradiated epidermal cells

International Nuclear Information System (INIS)

Sauder, D.N.; Tamaki, K.; Moshell, A.N.; Fujiwara, H.; Katz, S.I.

1981-01-01

Ultraviolet (uv) radiation has profound effects on the immune system both in vitro and in vivo. Recent studies, utilizing uv irradiation of intact animals, have focused on the suppressive effect of uv irradiation on the generation of allergic contact sensitization (ACS). To explore the mechanism(s) by which uv affects ACS, we used a recently described technique of sensitizing mice with the subcutaneous (s.c.) injection of haptenated epidermal cells. uv-treated or untreated mouse epidermal cells (EC) were conjugated with 1 mM trinitrobenzene sulfonate and injected s.c. into syngeneic recipients. Six days later the ear was challenged with 20 μl of 1% trinitrochlorobenzene (TNCB), and 24 h later ear thickness was measured. Our studies indicate that uv irradiation of EC prior to haptenation not only abrogates their capability of inducing ACS but also induces a state of specific immunologic tolerance. These studies indicate that the s.c. injection of trinitrophenyl conjugated (TNP) uv-irradiated (TNP-uv) EC induces a state of specific immunologic hyporesponsiveness, and passive transfer studies showed that this hyporesponsiveness is in part due to the generation of suppressor T-cells

Effects of feeding lactobacillus GG on lethal irradiation in mice

International Nuclear Information System (INIS)

Dong, M.Y.; Chang, T.W.; Gorbach, S.L.

1987-01-01

Mice exposed to 1400 rads of total body irradiation experienced 80%-100% mortality in 2 wk. Bacteremia was demonstrated in all dead animals. Feeding Lactobacillus GG strain reduced Pseudomonas bacteremia and prolonged survival time in animals colonized with this organism. In animals not colonized with Pseudomonas, feeding Lactobacillus GG also produced some reduction in early deaths, and there was less Gram-negative bacteremia in these animals compared with controls

Radiobiological speculations on therapeutic total body irradiation

International Nuclear Information System (INIS)

Vriesendorp, H.M.

1990-01-01

Unexpected total body irradiation (TBI) of human beings, involved in nuclear warfare or in accidents in nuclear reactors can be lethal. In the 1950s, bone marrow transplantation was discovered as a potentially life saving procedure after TBI in the dose range of 5.0 to 12.0 Gy. Since that time, deliberate or therapeutic TBI has been used to condition patients with a lethal bone marrow disorder for bone marrow replacement. The therapeutic ratio of TBI followed by bone marrow transplantation is small. Many potentially lethal complications can occur, such as acute TBI side effects, late TBI side effects or immunological complications of bone marrow transplantation such as graft versus host disease or graft rejection. The benefits of TBI and bone marrow transplantation are that they offer a chance for cure of previously lethal bone marrow disorders. The optimal parameters for TBI remain to be defined. The review discusses the current clinical and experimental animal data, as they relate to the future definition of less toxic TBI procedures with a better therapeutic ratio. Different TBI procedures are required for patients with malignant vs. non-malignant disorders or for patients with histoincompatible vs. histocompatible bone marrow donors.77 references

DNA polymerase I is crucial for the repair of potentially lethal damage caused by the indirect effects of X irradiation in Escherichia coli

International Nuclear Information System (INIS)

Billen, D.

1985-01-01

The radiosensitivity of an Escherichia coli mutant deficient in DNA polymerase I was measured in the presence of OH radical scavengers. The extreme X-ray sensitivity of the mutant could be abolished by OH radical scavengers if a sufficiently high level of radioprotector was present. There was a direct correlation between the OH radical scavenging activity of the chemicals tested (NO 2 - , n-butanol, glycerol, t-amyl alcohol, and t-butanol) and their protective ability. The author interprets the data as showing that the indirect actions of X rays (primarily OH radicals) result in major damage to the bacterial DNA which in large part consists of potentially lethal lesions. This potentially lethal damage is repaired through an enzymatic pathway requiring DNA polymerase I. I. In the mutant lacking DNA polymerase I, these potentially lethal lesions are expressed as cell lethality

Hematopoietic differentiative properties of murine spleen implanted in the omenta of irradiated and nonirradiated hosts

Energy Technology Data Exchange (ETDEWEB)

Haley, J E; Tjio, J H; Smith, W W; Brecher, G [California Univ., San Francisco (USA); National Inst. of Arthritis, Metabolism, and Digestive Diseases, Bethesda, Md. (USA); National Cancer Inst., Bethesda, Md. (USA). Lab. of Viral Oncology)

1975-01-01

Whole body irradiation of the recipients of syngeneic splenic implants into the omentum greatly enhances hematopoiesis and permits survival of and repopulation by stem cells of donor origin. Donor hematopoietic stem cells do not survive in spleen implants of the nonirradiated host.Irradiated hosts were therefore used in the bulk of the experiments. Differentiation in the implants of splenic fragments is predominantly erythrocytic at 10 days and shifts to predominantly granulocytic differentiation at 21 days. Suspensions of spleen cells injected into the omentum are predominantly granulocytopoietic at 10 days. The differentiation in fragments of spleen depleted of stem cells by irradiation, seeded with bone marrow cells and implanted into the omentum results in mixed erythrocytic and granulocytic hematopoiesis, with granulocytic predominance. Lymphocytic cells appeared late in the implants of irradiated recipients even at a time of prolific lymphocytopoiesis in the hosts' own spleens. The cause of the delay in the implants is not clear. The data are consistent with the concept that differentiation of hematopoietic stem cells is influenced by the stromal cells of the parent organ. The erythrocytic inductive capacity of the stromal cells may belost by mechanical disruption or modified by irradiation or a prolonged period of implantation.

Strand breaks and lethal damage in plasmid DNA subjected to 60CO-γirradiation

International Nuclear Information System (INIS)

Klimczak, U.

1992-01-01

Experiments with calf thymus DNA subjected to extracellular irradiation yield information on the role of direct and indirect effects in single-strand breakage, if this is evaluated with reference to the scavenger activity in respect of OH radicals. The role of the two processes in the occurrence of double-stand breaks and further damage leading to cell decay has so far remained largely obscure. It was the aim of the study described here to contribute to research in this field by performing in vitro experiments on biologically active DNA. For this purpose, DNA from pBR322 plasmids was irradiated in the presence of OH-radical scavengers. The number of single-strand and double-strand breaks was determined on the basis of the system's ability to eliminate OH radicals. In order to asses the influence of irradiation processes on the biological activity of DNA, investigations were carried out in E. coli for transformations caused by irradiated plasmid DNA. The results were interpreted in the light of theories about inhomogenous reaction kinetics put forward by Mark et al. (1989). It was finally discussed, which of the gamma-irradiation injuries occurring in DNA was to be held responsible for the inactivation of plasmid DNA and which enzymatic processes were additionally at work here. (orig./MG) [de

Blue light induced reactive oxygen species from flavin mononucleotide and flavin adenine dinucleotide on lethality of HeLa cells.

Science.gov (United States)

Yang, Ming-Yeh; Chang, Chih-Jui; Chen, Liang-Yü

2017-08-01

Photodynamic therapy (PDT) is a safe and non-invasive treatment for cancers and microbial infections. Various photosensitizers and light sources have been developed for clinical cancer therapies. Flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are the cofactor of enzymes and are used as photosensitizers in this study. Targeting hypoxia and light-triggering reactive oxygen species (ROS) are experimental strategies for poisoning tumor cells in vitro. HeLa cells are committed to apoptosis when treated with FMN or FAD and exposed to visible blue light (the maximum emitted wavelength of blue light is 462nm). Under blue light irradiation at 3.744J/cm 2 (=0.52mW/cm 2 irradiated for 2h), the minimal lethal dose is 3.125μM and the median lethal doses (LD 50 ) for FMN and FAD are 6.5μM and 7.2μM, respectively. Individual exposure to visible blue light irradiation or riboflavin photosensitizers does not produce cytotoxicity and no side effects are observed in this study. The western blotting results also show that an intrinsic apoptosis pathway is activated by the ROS during photolysis of riboflavin analogues. Blue light triggers the cytotoxicity of riboflavins on HeLa cells in vitro. Based on these results, this is a feasible and efficient of PDT with an intrinsic photosensitizer for cancer research. Copyright © 2017 Elsevier B.V. All rights reserved.

Antioxidative system in the liver of rates subjected to combined irradiation injury

International Nuclear Information System (INIS)

Simovic, M.; Stanimirovic, D.; Ivanovic, L.; Markovic, M.; Letic-Gavrilovic, A.; Jovic, P.; Savic, J.; Spasic, M.; Saicic, Z.S.

1991-01-01

Until the Chernobyl nuclear plant catastrophe, exposure to radiation combined with other forms of injuries was usually considered as a hazard of nuclear war. The effect of combined irradiation injuries are often defined as the simultaneous effect of irradiation and another noxious stimulus. In the authors' opinion (1) one may talk about combined irradiation injuries (CII) only in the case when the general response of an organism to traumatization is the combination of biological reactions to at least two different etiologic noxious stimuli of which one is irradiation. One of the basic problems of combined injuries in general and CII in particular, is the syndrome of mutual aggravation (SMA) expressed through a very high (potentiated) lethality. The real mechanism(s) of this syndrome is still unknown. In our model of combined irradiation injury, potentiation of irradiation effect was smaller if animals were irradiated in the hypometabolic (open-quotes ebbclose quotes) compared to the hypermetabolic (open-quotes flowclose quotes) phase after thermal injury. Since the oxygen uptake is greater in the hypermetabolic phase the free radical production is also greater. On the other hand, the transition of hypometabolic to hypermetabolic phase could be analogous to a hypoxia/reoxygenation state. According to Granger et al. this state induces an increase in free radical production. When irradiation injury follows scalding it induces a new flux of free radicals. As a result the antioxidative defense of an organism could be overwhelmed and a disturbance of oxidative-antioxidative processes might occur. Thus, the authors suppose that overwhelmed antioxidative defense could be the reason for potentiated lethality in combined irradiation injury. 12 refs., 2 tabs

Fibroblast implantation enhances wound healing as indicated by breaking strength determinations

Energy Technology Data Exchange (ETDEWEB)

Krueger, W W; Goepfert, H; Romsdahl, M; Hersen, J; Withers, R H; Jesse, R H

1978-09-01

Irradiation of normal tissues at the dose/time factor employed in the treatment of solid tumors impairs the subsequent healing of surgical wounds made in those tissues. Irreversible radiation damage to regional fibroblasts is one cause of impared healing. This study was conducted to determine whether syngeneic guinea pig fibroblasts is one cause of impared healing. This study was conducted to determine whether syngeneic guinea pig fibroblasts, harvested from tissue culture when injected into irradiated guinea pig skin at the time of wound closure, could improve wound healing. Breaking strength determinations indicate that irradiated wounds demonstrate enhanced wound healing if implanted with fibroblasts.

Anti-idiotypic antibodies against UV-induced tumor-specific CTL clones. Preparation in syngeneic combination

International Nuclear Information System (INIS)

Kuribayashi, K.; Tanaka, C.; Matsubayashi, Y.; Masuda, T.; Udono, H.; Abe, M.; Nakayama, E.; Shiku, H.

1988-01-01

In this study, we first established several CTL clones of (BALB/c x C57BL/6)F1 origin that were specific for either syngeneic UV female 1 or UV male 1 fibrosarcoma cell lines. All the CTL clones had Thy-1+ Lyt-2+ L3T4- phenotypes and showed Kd restriction when lysing the corresponding target cells. Sera obtained from syngeneic animals immunized with three CTL clones, 10B-5 for UV female 1, and CTL9 and CTL10 for UV male 1, showed specific inhibition of target cell lysis with the corresponding CTL clones. The inhibitory activities were found in sera of the majority of immunized animals. Because the inhibitory activity resides in protein A-binding fraction, mAb were produced by hybridizing spleen cells of hyperimmune animals. N1-56 was thus obtained from a mouse immunized with 10B-5 CTL clone reactive with UV female 1. N1-56 was clonotype specific, reacting with 10B-5 but not with other CTL lines or leukemia cell lines. No N1-56+ cells were detectable in thymocytes, lymph node cells, or spleen cells of either naive or UV female 1-immune CB6F1 mice. Immunoprecipitation showed that N1-56 reacts with 90,000 Mr molecules on 10B-5 CTL clone under nonreducing conditions and 45,000 Mr molecules under reducing conditions, indicating its reactivities with idiotypic determinants of TCR on the CTL clone. N1-56 inhibited lytic activity of 10B-5, but neither N1-56 nor alpha-10B-5 hyperimmune serum inhibited that of alpha-UV female 1 mixed lymphocyte tumor cell culture cells. N1-56 induced proliferation of 10B-5 without addition of Ag

Evidence for a decreased susceptibility to acute radiation lethality in young lambs

Energy Technology Data Exchange (ETDEWEB)

Roberts, P B [Department of Scientific and Industrial Research, Lower Hutt (New Zealand). Inst. of Nuclear Sciences; Pfeffer, A T [Ministry of Agriculture and Fisheries, Upper Hutt (New Zealand). Wallaceville Animal Research Centre

1980-08-01

The survival of 2- to 4-day old Romney-lambs was studied following bilateral /sup 60/Co irradiation at about 3.5 R/min (the exposure rate in air at the mid-line of the animal). Probit analysis of the data yielded an LDsub(50/60) of 900 R with 95% confidence limits of 700-1150 R. Mature sheep irradiated under similar conditions are known to have an LDsub(50/60) in the region of 250-350 R. These data indicate that very young lambs were less susceptible to radiation-induced hemopoietic failure than adults. Dorset Horn lambs and Romneys born by caesarian section also exhibited low susceptibility when irradiated at 2-4 days of age. There are few data available on LD/sub 50/ values for very young, large mammals (as opposed to rodents). Consideration must be given to the possibility that large mammals may be less sensitive to radiation-induced lethality shortly after birth than they are at maturity. Further work on the radiation response as a function of age after birth seems warranted and suggestions for some of the parameters which require investigation are made.

Adaptation dynamics of laboratory populations of Drosophila Melanogaster to low dose chronic ionizing irradiation

International Nuclear Information System (INIS)

Zajnullin, V.G.; Yushkova, E.A.

2008-01-01

In genetically non-uniform populations D. melanogaster in conditions of a chronic irradiation in a doze 10-11 about sGy/generation dynamics parameters of populations was investigated. It is established, that number of individuals in irradiated populations is lower, than in control. It is revealed, that viability of populations undergone to a chronic irradiation depends on their genotype. The gradual increase in fruitfulness, viability of individuals and decrease in a level of lethal mutations in a number of generations after of an irradiation in low doses is caused by adaptable opportunities of populations. (authors)

Food irradiation

Energy Technology Data Exchange (ETDEWEB)

Beerens, H [Lille-1 Univ., 59 - Villeneuve-d' Ascq (France); Saint-Lebe, L

1979-01-01

Various aspects of food treatment by cobalt 60 or caesium 137 gamma radiation are reviewed. One of the main applications of irradiation on foodstuffs lies in its ability to kill micro-organisms, lethal doses being all the lower as the organism concerned is more complex. The effect on parasites is also spectacular. Doses of 200 to 300 krad are recommended to destroy all parasites with no survival period and no resistance phenomenon has ever been observed. The action of gamma radiation on macromolecules was also investigated, the bactericide treatment giving rise to side effects by transformation of food components. Three examples were studied: starch, nucleic acids and a whole food, the egg. The organoleptic aspect of irradiation was examined for different treated foods, then the physical transformations of unpasteurized, heat-pasteurized and radio-pasteurized eggs were compared. The report ends with a brief analysis of the toxicity and conditions of application of the treatment.

Food irradiation

International Nuclear Information System (INIS)

Beerens, H.; Saint-Lebe, L.

1979-01-01

Various aspects of food treatment by cobalt 60 or caesium 137 gamma radiation are reviewed. One of the main applications of irradiation on foodstuffs lies in its ability to kill micro-organisms, lethal doses being all the lower as the organism concerned is more complex. The effect on parasites is also spectacular. Doses of 200 to 300 krad are recommended to destroy all parasites with no survival period and no resistance phenomenon has ever been observed. The action of gamma radiation on macromolecules was also investigated, the bactericide treatment giving rise to side effects by transformation of food components. Three examples were studied: starch, nucleic acids and a whole food, the egg. The organoleptic aspect of irradiation was examined for different treated foods, then the physical transformations of unpasteurized, heat-pasteurized and radio-pasteurized eggs were compared. The report ends with a brief analysis of the toxicity and conditions of application of the treatment [fr

Action of sulfured radioprotectors on spontaneous cerebral electric activity of implanted chronic non irradiated adult rabbit

International Nuclear Information System (INIS)

Fatome, M.

In a previous study, the radioprotective action of serotonin on central nervous system of lethal dose irradiated rabbit had been determined. In the present study, the possibilities of sulfured radioprotectors were considered in order to see if these products have by themselves an action on central nervous system of non irradiated animals [fr

Insect radiosensitivity: dose curves and dose-fractionation studies of dominant lethal mutations in the mature sperm of 4 insect species

International Nuclear Information System (INIS)

LaChance, L.E.; Graham, C.K.

1984-01-01

Males of 4 species of insects: Musca domestica L. (housefly) (Diptera), Oncopeltus fasciatus (Dallas) (milkweed bug) (Hemiptera), Anagasta kuhniella (Zeller) (mealmoth) (Lepidoptera) and Heliothis virescens (Fab.) (tobacco budworm) (Lepidoptera) were irradiated as adults. Dose-response curves for the induction of dominant lethal mutations in the mature sperm were constructed. The curves were analyzed mathematically and compared with theoretical computer simulated curves requiring 1, 2, 4, 8 and 16 'hits' for the induction of a dominant lethal mutation. The 4 species belonging to 3 different orders of insects showed a wide range in radiation sensitivity and vastly different dose-response curves. When the data were analyzed by several mathematical models the authors found that a logistic response curve gave reasonably good fit with vastly different parameters for the 4 species. Dose-fractionation experiments showed no reduction in the frequency of lethal mutations induced in any species when an acute dose was fractionated into 2 equal exposures separated by an 8-h period. (Auth.)

Function of skeletal muscle tissue formed after myoblast transplantation into irradiated mouse muscles.

Science.gov (United States)

Wernig, A; Zweyer, M; Irintchev, A

2000-01-15

1. Pretreatment of muscles with ionising radiation enhances tissue formation by transplanted myoblasts but little is known about the effects on muscle function. We implanted myoblasts from an expanded, male-donor-derived, culture (i28) into X-ray irradiated (16 Gy) or irradiated and damaged soleus muscles of female syngeneic mice (Balb/c). Three to 6 months later the isometric contractile properties of the muscles were studied in vitro, and donor nuclei were visualised in muscle sections with a Y chromosome-specific DNA probe. 2. Irradiated sham-injected muscles had smaller masses than untreated solei and produced less twitch and tetanic force (all by about 18 %). Injection of 106 myoblasts abolished these deficiencies and innervation appeared normal. 3. Cryodamage of irradiated solei produced muscle remnants with few (1-50) or no fibres. Additional myoblast implantation led to formation of large muscles (25 % above normal) containing numerous small-diameter fibres. Upon direct electrical stimulation, these muscles produced considerable twitch (53 % of normal) and tetanic forces (35 % of normal) but innervation was insufficient as indicated by weak nerve-evoked contractions and elevated ACh sensitivity. 4. In control experiments on irradiated muscles, reinnervation was found to be less complete after botulinum toxin paralysis than after nerve crush indicating that proliferative arrest of irradiated Schwann cells may account for the observed innervation deficits. 5. Irradiation appears to be an effective pretreatment for improving myoblast transplantation. The injected cells can even produce organised contractile tissue replacing whole muscle. However, impaired nerve regeneration limits the functional performance of the new muscle.

Quantitative determination of the contribution of indirect and direct radiation action to the production of lethal lesions in mammalian cells

International Nuclear Information System (INIS)

Pohlit, W.; Drenkard, S.

1985-01-01

For quantitative models of radiation action in living cells it is necessary to know what fraction of the absorbed dose affects the target molecule by direct radiation action and what fraction by indirect radiation action. Mammalian cells were irradiated in suspension, saturated with N 2 O or CO 2 . With these gases the production of OH-radicals is changed by a factor of two in aqueous solutions and a corresponding change in cell survival would be expected, if only indirect radiation action is involved in the production of lethal lesions in the living cell. No difference could be detected, however, and it is concluded that indirect radiation action does not contribute to radiation lethality in mammalian cells. (author)

Factors influencing circadian rhythms in acetaminophen lethality.

Science.gov (United States)

Schnell, R C; Bozigian, H P; Davies, M H; Merrick, B A; Park, K S; McMillan, D A

1984-01-01

Experiments were conducted to examine the effects of changes in lighting schedules and food consumption on circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice. Under a normal lighting schedule (light: 06.00-18.00 h), male mice exhibited a circadian rhythm in acetaminophen lethality (peak: 18.00 h; nadir: 06.00, 10.00 h) and an inverse rhythm in hepatic glutathione concentrations (peak: 06.00, 10.00 h; nadir: 18.00 h). Under a reversed lighting schedule (light: 18.00-06.00 h) the glutathione rhythm was reversed and the rhythm in acetaminophen lethality was altered showing greater sensitivity to the drug. Under continuous light, there was a shift in the acetaminophen lethality and the hepatic glutathione rhythms. Under continuous dark, both rhythms were abolished. Under a normal lighting regimen, hepatic glutathione levels were closely correlated with food consumption; i.e., both were increased during the dark phase and decreased during the light phase. Fasting the mice for 12 h abolished the rhythms in acetaminophen lethality and hepatic glutathione levels; moreover, the lethality was increased and the hepatic glutathione levels were decreased. These experiments show that both lighting schedules and feeding can alter the circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice.

Lack of immunoglobulin M suppression by immunoglobulin G antibody in thymectomized, irradiated, and bone marrow-reconstituted mice infected with Toxoplasma gondii.

Science.gov (United States)

Aryanpour, J; Hafizi, A; Modabber, F

1980-03-01

Thymectomized, irradiated, bone marrow-reconstituted (T-deprived) mie infected with an avirulent strain of Toxoplasma gondii produced antibody titers comparable to those produced in intact syngeneic mice. Both immunoglobulin M (IgM) and IgG antibodies were produced in T-deprived animals; however, the IgM antibody remained constant in the presence of increasing amounts of IgG. In the intact animals, IgM became undetectable by day 50 postinfection as expected. Feedback inhibition of IgM by IgG seems to be dependent upon T-cells in Toxoplasma-infected mice.

Suppression of adoptive antituberculosis immunity by normal recipient animals

International Nuclear Information System (INIS)

Lefford, M.J.

1983-01-01

Adoptive immunity is poorly expressed in normal syngeneic mice. This phenomenon was studied by using experimental antituberculosis immunity as a model system representing pure cell-mediated immunity. Expression of adoptive immunity was facilitated by pretreating recipients with sublethal ionizing radiation (500 rads) or high doses (200 mg/kg) of cyclophosphamide or by using adult thymectomized, lethally irradiated, bone-marrow-reconstituted (TXB) mice. Adult thymectomy was less effective, and a low dose of cyclophosphamide (20 mg/kg) was completely ineffective. The beneficial effect of sublethal irradiation was reduced over time; it persisted for 4 weeks and was absent after 8 weeks. Attempts to restore the suppressed state of normal mice to sublethally irradiated mice by using normal spleen or thymus cells did not succeed. Even in rats, which express adoptive antituberculosis immunity without immunosuppressive treatment, the use of sublethally irradiated or TXB recipients potentiated adoptive immunity. It was concluded that suppression of adoptive immunization in normal recipient mice is mediated predominantly, if not exclusively, by T lymphocytes that are sensitive to a number of immunosuppressive agents. The suppressor cells are long-lived and can be regenerated from precursors that are resistant to 500 but not to 900 rads of ionizing radiation

A comparative study of post-irradiation growth kinetics of spheroids and monolayers

International Nuclear Information System (INIS)

Dertinger, J.; Luecke-Huhle, C.

1975-01-01

Post-irradiation growth kinetics of γ-irradiated spheroid and monolayer cells in exponential growth phase was investigated by means of dose-response curves based on cell counts after specified time intervals following irradiation. A mathematical model of cell-growth after irradiation was fitted to these curves. The model parameters (related to division delay and growth of non-surviving cells) obtained from this analysis consistently indicated increasing resistance to sub-lethal damage of cells cultured as multicellular spheroids under conditions of increasing three-dimensional contact. In contrast, no indication of an increased radiation-resistance was found with cells cultured on a substratum under a variety of conditions. (author)

Enhancement of the effect of X-irradiation against cultured human glioblastoma cells by pretreatment with ACNU

Energy Technology Data Exchange (ETDEWEB)

Mashiyama, Shoji; Katakura, Ryuichi; Takahashi, Kou; Kitahara, Masakazu; Suzuki, Jiro [Tohoku Univ., Sendai (Japan). Inst. of Brain Diseases; Sasaki, Takehito

1989-12-01

Human glioblastoma A-7 (GB A-7) cells can apparently recover from potentially lethal X-irradiation. The authors, using a colony-forming assay, studied the influence of pretreatment with 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3- (2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) on the effectiveness of X-irradiation against GB A-7 cells grown in monolayers and as multicellular spheroids. Pre-exposure to ACNU inhibited the recovery of irradiated GB A-7 cells. In monolayer cells, the combination treatment was most effective when ACNU was applied 2 to 8 hours prior to irradiation, and the larger the X-ray dose, the more potent the effect. ACNU pretreatment was more effective against large spheroids (enhancement ratio 1.86) than against small ones (1.34). Large spheroids showed necrosis, whereas small ones did not. Isobolographic analysis disclosed that the effect of combining X-irradiation and ACNU is within an additive envelope at the surviving fraction of 10{sup -2}, while supra-additive at the surviving fraction of 10{sup -3}. These results suggest that the potency of X-irradiation is augmented by ACNU pretreatment through an interactive mechanism. Further, suppression of recovery from X-ray induced potentially lethal damage was influenced by the presence of necrosis. (author).

Enhancement of the effect of X-irradiation against cultured human glioblastoma cells by pretreatment with ACNU

International Nuclear Information System (INIS)

Mashiyama, Shoji; Katakura, Ryuichi; Takahashi, Kou; Kitahara, Masakazu; Suzuki, Jiro; Sasaki, Takehito.

1989-01-01

Human glioblastoma A-7 (GB A-7) cells can apparently recover from potentially lethal X-irradiation. The authors, using a colony-forming assay, studied the influence of pretreatment with 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3- (2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) on the effectiveness of X-irradiation against GB A-7 cells grown in monolayers and as multicellular spheroids. Pre-exposure to ACNU inhibited the recovery of irradiated GB A-7 cells. In monolayer cells, the combination treatment was most effective when ACNU was applied 2 to 8 hours prior to irradiation, and the larger the X-ray dose, the more potent the effect. ACNU pretreatment was more effective against large spheroids (enhancement ratio 1.86) than against small ones (1.34). Large spheroids showed necrosis, whereas small ones did not. Isobolographic analysis disclosed that the effect of combining X-irradiation and ACNU is within an additive envelope at the surviving fraction of 10 -2 , while supra-additive at the surviving fraction of 10 -3 . These results suggest that the potency of X-irradiation is augmented by ACNU pretreatment through an interactive mechanism. Further, suppression of recovery from X-ray induced potentially lethal damage was influenced by the presence of necrosis. (author)

Ultraviolet irradiation mutagenesis and recombination in spiroplasma citri

Energy Technology Data Exchange (ETDEWEB)

Labarere, J.; Barroso, G. (Bordeaux-2 Univ., 33 (France))

1984-09-01

A method for obtaining and screening uv-induced mutants from Spiroplasma citri is described. Lethality response curves showed that S. citri is more sensitive to uv irradiation than are other microorganisms. The presence of a shoulder in the lethality response curve showed the existence of systems able to repair uv-induced DNA damages. Toxic-resistant mutants have been obtained. A uv fluence equal to 10 J/m/sup 2/ multiplied by 2.5x10/sup 3/ gave the spontaneous mutation frequency. Arsenic acid- and xylitol-resistant mutants were used to investigate transfer of genetic information in S. citri. After 90 min of incubation, the recombination frequency was 5x10/sup -5/.

Mutagenicity studies on alcohol extracts from gamma-irradiated potatoes

International Nuclear Information System (INIS)

Shibuya, Tohru; Murora, Tetsuro; Iwahara, Shigeo; Hashimoto, Koroku; Minegishi, Atsuko.

1982-01-01

Alcohol extracts freshly prepared from gamma-irradiated and unirradiated potatoes were tested for the ability to induce dominant lethals in BDF 1 mice. Male mice were given 0.5 ml of extract twice a day, p.o., for 7 days and then mated with untreated female mice. Female mice were sacrificed on about the 13th day of pregnancy. No significant difference was observed in the number of living inplants between the group treated with extract prepared from unirradiated potatoes and that treated with the extract from 150 Gy (15 krad) irradiated potatoes. (author)

Lethal effects of solar radiation in proficient and deficient bacteria in repair systems

International Nuclear Information System (INIS)

Sousa Neto, A. de.

1980-01-01

A study of the lethal action of solar radiation on strains of E.coli K12, proficient or deficient in repair systems, as well as the wild type strain gene products are involved in repair of damage induced by solar radiation. The inactivation of the various bacterial strains (normalized to a dose equivalent to radiation at a wavelength 254 nm) suggests that the more energetic wavelengths of the solar spectrum (290-320 nm) could be responsible for the primary damage that occurs in the DNA. The reduction in the shoulder of the survival curve in wild type strains in indicative of induction of sub-lethal damage in this region of the curve. Analysing solar inactivation curves of the bacterial strains (normalised by spore dosimetry) together with those of the same strains irradiated with UV at 254 nm, it was evident that 254 nm is not the ideal wavelength for comparison. This analysis also indicated that in addition to damage to DNA, other factors are involved in the solar radiation inactivation of wild type strains. (author)

Amelioration of radiation damage to haemopoiesis by Ivastimul, given after irradiation to mice protected by peroral cystamine

International Nuclear Information System (INIS)

Vacek, A.; Rotkovska, D.; Bartonickova, A.; Kautska, J.

1992-01-01

Combined radioprotection by preirradiation peroral cystamine and postirradiation Ivastimul administration was examined in sublethally and lethally whole-body gamma-irradiated mice. Enhancement of haemopoietic recovery and increased survival of irradiated mice was demonstrated for a single dose of Ivastimul administered after irradiation. The ameliorative influence of combined radioprotection may be explained by haemopoietic stem cell protection by cystamine and haemopoietic stimulation mediated by Ivastimul. (author) 2 tabs., 3 figs., 20 refs

Influence of UV-irradiation on the nauplius larvae of the barnacle Chthamalus sp

International Nuclear Information System (INIS)

Hori, Masayuki; Nagayama, Shougo; Kawabe, Atsushi; Yamashita, Keiji.

1990-01-01

The purpose of this study is to investigate the influence of UV-irradiation on the nauplius larvae of the barnacle and to use this as the basis for researching the possibility of UV-irradiation as a new method for anti-macrofouling control. The nauplius larvae in the petri dishes were exposed to UV-irradiation (λ max = 253.7 nm), then the larval states and behaviour were observed. UV-intensisties were 3.0 mW·cm -2 -7.0 mW·cm -2 and the exposure time was 15 sec -10 min. The water in the petri dishes was changed intermittently but the larvae were not fed. The results were as follows: 1) UV-irradiation may have a delayed lethal effect and metamorphosis-inhibitory effect on the nauplius larvae. 2) The lethal effect of the sum of the dosages of UV on the larvae may nearly equate each other despite differences in each UV-intensity. 3) Within ca. 72 hr, 100 % of UV-irradiated larvae were dead with the dosage of at least 672 mW·sec·cm -2 and were incapable of swimming with the dosage of at least 168 mW·sec·cm -2 . 4) UV-irradiated larvae could not exuviate with the dosage of at least 246 mW·sec·cm -2 and could only exuviate with the dosage of 45 mW·sec·cm -2 . 5) After UV-irradiation even the 'actively swimming' larvae may have suffered some sort of physiological damage. (author)

Effects of sub-lethal dose of gamma-irradiation on levels of acid phosphatase in cerebellum of pigeons

International Nuclear Information System (INIS)

Shah, V.C.; Gadhia, P.K.

1980-01-01

The changes in the activities of acid phosphatase in the sham-irradiated and γ-irradiated cerebellum of pigeons have been studied both biochemically as well as histochemically after 400 rads. The specific activity of acid phosphatase decreased significantly after 48h and 72h of irradiation. The histochemical observations following total body irradiation confirmed the results obtained by quantitative biochemical studies. (author)

Proliferation differentiation and therapeutic effect of short-term cultured murine bone marrow cells

International Nuclear Information System (INIS)

Zhao Zekun; Cong Jianbo

1986-01-01

Murine bone marrow cells were cultured in conditioned medium of muscle. After 24 hours of culture, both adherent and suspended cells appeared in the culture. The adherent cells mainly consisted of macrophages and the suspended cells were predominantly granulocytes. After 6 days, the total number of nucleated cells and CFU-C in the culture increased about 400% and 600% respectively, but CFU-S reduced to 21% approximately. Lymphocytes persisted only for 4 days. The stem cells (CFU-S) from 6-day culture were injected into the lethally irradiated syngenic mice. The 30 day survival rate of the treated mice was 89% whereas that of the controls was only 7%. The bone marrow cells in 2/8 of recipients sacrificed at 30 or 60 days were of donor type and 6/8 of the recipients were chimeras

Histochemical study on effects of low dose γ-irradiation on acid phosphatase in liver of the pigeons Columbus livia intermedia Strickland

International Nuclear Information System (INIS)

Gadhia, P.K.; Shah, V.C.

1982-01-01

Effects of total body γ-irradiation with sub-lethal dose (400 rads) on acid phosphatase have been studied in the liver of pigeon. The histochemical study showed increased activity of acid phosphatase in liver after 48 hr and 72 hr of irradiation. (author)

Use of lymphokine-activated killer cells to prevent bone marrow graft rejection and lethal graft-vs-host disease

International Nuclear Information System (INIS)

Azuma, E.; Yamamoto, H.; Kaplan, J.

1989-01-01

Prompted by our recent finding that lymphokine-activated killer (LAK) cells mediate both veto and natural suppression, we tested the ability of adoptively transferred LAK cells to block two in vivo alloreactions which complicate bone marrow transplantation: resistance to transplanted allogeneic bone marrow cells, and lethal graft-vs-host disease. Adoptive transfer of either donor type B6D2 or recipient-type B6 lymphokine-activated bone marrow cells, cells found to have strong LAK activity, abrogated or inhibited the resistance of irradiated B6 mice to both B6D2 marrow and third party-unrelated C3H marrow as measured by CFU in spleen on day 7. The ability of lymphokine-activated bone marrow cells to abrogate allogeneic resistance was eliminated by C lysis depletion of cells expressing asialo-GM1, NK1.1, and, to a variable degree, Thy-1, but not by depletion of cells expressing Lyt-2, indicating that the responsible cells had a LAK cell phenotype. Similar findings were obtained by using splenic LAK cells generated by 3 to 7 days of culture with rIL-2. Demonstration that allogeneic resistance could be blocked by a cloned LAK cell line provided direct evidence that LAK cells inhibit allogeneic resistance. In addition to inhibiting allogeneic resistance, adoptively transferred recipient-type LAK cells prevented lethal graft-vs-host disease, and permitted long term engraftment of allogeneic marrow. Irradiation prevented LAK cell inhibition of both allogeneic resistance and lethal graft-vs-host disease. These findings suggest that adoptive immunotherapy with LAK cells may prove useful in preventing graft rejection and graft-versus-host disease in human bone marrow transplant recipients

Histological variations in liver of freshwater fish Oreochromis mossambicus exposed to 60Co gamma irradiation

International Nuclear Information System (INIS)

Sadiq Bukhari, A.; Syed Mohamed, H.E.; Broos, K.V.; Stalin, A.; Singhal, R.K.; Venubabu, P.

2012-01-01

The irradiation effect of 60 Co at the three dose level of 3 mGy, 30 mGy and 300 mGy on the histology of liver of the freshwater fish Oreochromis mossambicus was investigated. The liver of O. mossambicus was dissected out and processed for light microscopy studies. 60 Co exposed O. mossambicus were found to result in several alterations in the histoarchitecture of liver. The alterations included mild congestion of blood vessels, structural alteration, cellular swelling, vacuolation and necrotic liver cells, indicating a definite response to 60 Co irradiation. The results suggest that the liver of O. mossambicus exposed to 60 Co were structurally altered with increasing dose levels. It is to record that alteration in the liver does not affect the physiology, behaviour or lethality of the individuals. Self regulating mechanisms would have influenced the liver to remain sustained. To confirm the same further studies in the direction by increasing dose level is required. - Highlights: ► Fish Oreochromis mossambicus irradiated to the dose of 3 mGy, 30 mGy and 300 mGy. ► Histoarchitecture of liver altered with increasing dose levels of 60 Co. ► Alteration in the liver does not affect the physiology, behaviour or lethality. ► Self regulating mechanisms might have prevented from Lethality. ► HSI index value for exposed group reported ( 60 Co.

Quantitative changes in the arterial blood gases of mice following localized irradiation of the lungs

International Nuclear Information System (INIS)

Siemann, D.W.; Hill, R.P.

1983-01-01

The arterial pH and partial pressures of oxygen (PaO 2 ) and carbon dioxide (PaCO 2 ) were evaluated in LAF1 mice 15 and 38 weeks after localized irradiation of the animals' thoraxes. Graded radiation doses of 900 to 1200 rad were administered. These doses resulted in 0 to 100% lethality by 26 weeks (180 days) after irradiation. At 15 weeks after treatment mice receiving radiation doses which would subsequently result in lethality (by 180 days) exhibited significant reductions in their PaO 2 and elevations in their PaCO 2 values, respectively. However, there was no clear dose-response relationship between blood gas values and radiation dose, which may reflect the animals' ability to compensate for their poor blood gas exchange by an increased breathing frequency. At 38 weeks after irradiation the blood gas values were abnormal in mice from groups which had normal blood gas values at Week 15 (and no fatalities by Week 26) but in which animal deaths had occurred between Weeks 26 and 38. These data therfore indicated (i) that abnormal blood gas values occurred in the mice prior to fatalities resulting from the acute radiation pneumonitis syndrome and (ii) that mice surviving the initial radiation pneumonitis phase could still succumb to progressive pulmonary toxicity which was reflected by the increasing levels of animal lethality and altered blood gas tensions at the later times

Change in the dibenzyldimethylammonium accumulation by irradiated Streptococcus cells caused by radiation damage modifiers

International Nuclear Information System (INIS)

Fomenko, B.S.; Leont'eva, G.A.

1975-01-01

Anoxia, concentrated cell suspension, glutathione (10 -4 -10 -2 M) or low concentrations of cysteine (10 -4 -10 -3 M) exerted a radioprotective effect and suppressed the accumulation of dibenzyldimethylammonium chloride (DDA + ) by γ-irradiated (40 krad) S. faecalis cells. Dilution of the cell suspensions and higher cysteine concentrations (>10 -3 M) increased the effects of irradiation on bacterial accumulation of DDA + and decreased the cell survival. The lethal action of irradiation apparently involves damage to the mechanisms which maintain a normal membrane potential

Delayed cell death, giant cell formation and chromosome instability induced by X-irradiation in human embryo cells

International Nuclear Information System (INIS)

Roy, K.; Kodama, Seiji; Suzuki, Keiji; Watanabe, Masami

1999-01-01

We studied X-ray-induced delayed cell death, delayed giant cell formation and delayed chromosome aberrations in normal human embryo cells to explore the relationship between initial radiation damage and delayed effect appeared at 14 to 55 population doubling numbers (PDNs) after X-irradiation. The delayed effect was induced in the progeny of X-ray survivors in a dose-dependent manner and recovered with increasing PDNs after X-irradiation. Delayed plating for 24 h post-irradiation reduced both acute and delayed lethal damage, suggesting that potentially lethal damage repair (PLDR) can be effective for relieving the delayed cell death. The chromosome analysis revealed that most of the dicentrics (more than 90%) observed in the progeny of X-ray survivors were not accompanied with fragments, in contrast with those observed in the first mitosis after X-irradiation. The present results indicate that the potentiality of genetic instability is determined during the repair process of initial radiation damage and suggest that the mechanism for formation of delayed chromosome aberrations by radiation might be different from that of direct radiation-induced chromosome aberrations. (author)

Lethal and sublethal cellular injury in multifraction irradiation

International Nuclear Information System (INIS)

Withers, H.R.

1975-01-01

Work has been carried out on cellular injury in multifraction irradiation of mouse tissues and compared with similar work on human skin reported earlier by Dutreix et al (Eur. J. Cancer.; 9:159 (1973)). In agreement with Dutreix et al it is emphasized that the absolute amount of sublethal injury repaired per fractionation interval (Dsub(r)) is not as important to radiotherapists as the change in the amount repaired (ΔDsub(r)) when the dose-per-fraction is altered. It was found that although there is a critical divergence at low doses, the data for mouse tissues are similar to those previously given for human skin and support the conclusions: (i) That the capacity of many normal cells for accumulating and repairing sublethal radiation injury is probably not greatly different. (ii) That fixed exponents used for fraction number and time in iso-effect formulae are inaproporiate. At low doses-per-fraction, repair of sublethal injury is complete, or nearly so, and hence, additional fractionation of dose does not give appreciable additional sparing, whereas rapidly-regenerating tissues, due to the lengthening of overall time, would continue being spared by repopulation. (U.K.)

Protective effect of zinc against lethality of the irradiated mice

International Nuclear Information System (INIS)

Matsubara, J.; Inada, T.; Machida, K.

1982-01-01

The effects of adding 1000 ppm Zn in the drinking water 10 days before gamma irradiation (562 - 1000 rad) of mice were studied. The mice which had received zinc had a lower mortality rate and a longer survival time compared to the controls. The LD 50 of gamma radiation was 690 rad in the control group and 770 rad in the zinc group. Zinc added to the culture medium of human melanoma cells did not shown any change in radiosensitivity; thus the radioprotective effect of zinc appears to work at the whole body level. (U.K.)

Comparison of UV action spectra for lethality and mutation in Salmonella typhimurium using a broad band source and monochromatic radiations

International Nuclear Information System (INIS)

Calkins, John; Selby, Christopher; Enoch, H.G.

1987-01-01

The UV-B region (280-320 nm) is thought to be primarily responsible for the mutagenic, lethal, and carcinogenic effects of solar radiation. We have conducted UV-B action spectroscopy for mutagenesis and survival of Ames' Salmonella typhimurium strain TA98 (uvrB, pKM101) using both monochromatic radiation from a dye laser and broader bandwidth radiation emitted from FS-20 sunlamps. A series of optical filters having different transmission cut-offs together with the sunlamp source provided bandwidths having successively less short wavelength components from which a ''broad band'' action spectrum was deduced. The two sets of action spectra differed both qualitatively and quantitatively: in comparison to the monochromatic action spectra, the ''broad band'' spectra showed up to a 200-fold reduced efficiency for both mutation induction and lethality by UV-B wavelengths. These results suggest a large protective effect of the background UV-A and/or visible radiations which were present during the broad spectrum irradiations and which are also present in solar radiation. Additional experiments show that to the extent tested this protective effect is not due to photo-reactivation or irradiance (dose rate) effects. (author)

A comparison of mutagenic effects of common wheat by electron beam, fast neutron and 60Co gamma ray irradiation

International Nuclear Information System (INIS)

An Daochang; Wang Linqing

1988-02-01

After winter wheat was irradiated by electron beam, fast neutron and γ-rays, respectively, the RBE value of electron beam to both fast neutrons and γ-rays was less than one, the RBE value of fast neutron to γ-rays was largely more than one. This results indicated that biological effect of M 1 generation induced by electron beam was less than that of fast neutrons very much, and similar to γ-ray irradiation. With electron beam irradiation, the half-lethal doses of M 1 generation were from 185 to 370 Gy, closer to 370 Gy, the lethal doses from 740 to 925 Gy. M 2 mutation efficiency with electron beam treatment was larger as compared with that with both fast neutrons and γ-rays. A wider mutation spectrum and higher mutation efficiency compared with other physical mutagens can be obtained with electron beam irradiation, about 30% higher than that with γ-ray irradiation. The best doses of irradiation with electron beam were 370 to 555 Gy. Fast neutrons, a better dose of which was 25 Gy, could induce more mutants than that with γ-rays in M 2 generation. The dose in which biological injury reached to 50% was the best dose for M 2 mutants by electron beam irradiation

Lethal and sub-lethal effects of five pesticides used in rice farming on the earthworm Eisenia fetida

NARCIS (Netherlands)

Rico, Andreu; Sabater, Consuelo; Castillo, María Ángeles

2016-01-01

The toxicity of five pesticides typically used in rice farming (trichlorfon, dimethoate, carbendazim, tebuconazole and prochloraz) was evaluated on different lethal and sub-lethal endpoints of the earthworm Eisenia fetida. The evaluated endpoints included: avoidance behaviour after an exposure

Todralazine protects zebra fish from lethal doses of ionizing radiation: role of hematopoietic stem cell expansion

International Nuclear Information System (INIS)

Dimri, Manali; Joshi, Jaidev; Indracanti, Prem Kumar

2013-01-01

Radiation induced cell killing and hematopoietic stem cell depletion leads to compromised immune functions and opportunistic infections which significantly affect the recovery and survival upon irradiation. Any agent which can expand residual hematopoietic stem cells in irradiated organism can render protection from the effects of lethal doses of ionizing radiation. Johns Hopkins Clinical compound library (JHCCL) was screened for protection against lethal doses of ionizing radiation using developing zebra fish as a model organism. Modulation of radiation induced reactive oxygen species by the small molecules were done by DCFDA staining and for visual identification and quantification of apoptosis acridine orange assay, flow cytometry were employed respectively. Hematopoietic stem cell expansion potential was assessed by quantifying runx1 expression, a marker for definitive stem cells, were done by RT-PCR and by the kinetics of recovery from chemically induced anaemia. Todralazine hydrochloride from JHCCL exhibited promising results with potential anti radiation effects. A dose of 5μM was found to be the most effective and has rendered significant organ and whole body protection (100% survival advantage over a period of 6 days) against 20 Gy. However todralazine did not modulated radiation induced free radicals (monitored within 2 h of irradiation) and apoptosis in zebra fish embryos analysed at 8 and 24h post irradiation. Flow cytometric quantification of pre G1 population suggested the same. Chemoinformatics approaches were further carried out to elucidate possible targets which are contributing to its radioprotection potential. Structural similarity search suggested several targets and possible hematopoietic stem cell expanding potential. Treatment of zebra fish embryos with todralazine has lead to significant proliferation of hematopoietic stem cell as indicated by increase in expression of runx1. HSC expanding potential of todralazine was further supported by

Expression of antigens coded in murine leukemia viruses on thymocytes of allogeneic donor origin in AKR mice following syngeneic or allogeneic bone marrow transplantation

International Nuclear Information System (INIS)

Wustrow, T.P.; Good, R.A.

1985-01-01

Removal of T-lymphocytes from marrow inoculum with monoclonal antibody plus complement permitted establishment of long-lived allogeneic chimeras between C57BL/6 and AKR/J mice. Development of leukemia was prevented for 15 mo. Protection from leukemia occurred with both young (4 wk) and older (4 mo) recipients. AKR mice reconstituted with syngeneic marrow or control AKR mice all developed leukemia-lymphoma before 1 yr of age. During spontaneous lymphomagenesis in AKR mice, amplified expression of gag or env gene-coded virus antigens on the surface of thymocytes preceded leukemia development and evidence for amplification of other virus genes. These changes generally appeared before 6 mo. Similar viral gene expression and viral gene amplification occurred in the thymus and spleen cells of leukemia-resistant chimeric mice. Using monoclonal antibodies to Mr 70,000 glycoprotein epitopes characteristic of ecotropic, xenotropic, or dualtropic viruses, antigens marking each virus form were found on thymocytes of allogeneic 4-wk and 4-mo chimeras as well as on the cells of AKR mice and of AKR mice reconstituted with syngeneic marrow. Flow cytometric analysis showed amplification of the virus genes in mice protected from leukemia-lymphoma by allogeneic bone marrow transplantation from leukemia-resistant mice. Allogeneic chimeras and syngeneically transplanted mice both showed evidence of accelerated viremia and of recombinant virus formation. The findings suggest that an event essential to leukemogenesis which occurs within the AKR lymphoid cells or their environment is lacking in the allogeneic chimeras. The nature of this influence of a resistance gene or genes introduced into AKR mice by allogeneic bone marrow transplantation deserves further study

Lethal Epistaxis.

Science.gov (United States)

Byard, Roger W

2016-09-01

Epistaxis or nosebleed refers to bleeding from the nostrils, nasal cavity, or nasopharynx. Occasional cases may present with torrential lethal hemorrhage. Three cases are reported to demonstrate particular features: Case 1: A 51-year-old woman with lethal epistaxis with no obvious bleeding source; Case 2: A 77-year-old man with treated nasopharyngeal carcinoma who died from epistaxis arising from a markedly neovascularized tumor bed; Case 3: A 2-year-old boy with hemophilia B who died from epistaxis with airway obstruction in addition to gastrointestinal bleeding. Epistaxis may be associated with trauma, tumors, vascular malformations, bleeding diatheses, infections, pregnancy, endometriosis, and a variety of different drugs. Careful dissection of the nasal cavity is required to locate the site of hemorrhage and to identify any predisposing conditions. This may be guided by postmortem computerized tomographic angiography (PCTA). Despite careful dissection, however, a source of bleeding may never be identified. © 2016 American Academy of Forensic Sciences.

Protective effect of Asparagus racemosus root extract against lethal total - body electron beam radiation induced damage in Swiss albino mice

International Nuclear Information System (INIS)

Sharmila, K.P.; Bhandary, B. Satheesh Kumar; Suchetha Kumari, N.; Bhat, Vadish S.; Shetty, Jayaram; Peter, Alex John; Jose, Jerish M.; Fernandes, Ronald

2016-01-01

To investigate the protective effect of Asparagus Racemosus Root ethanolic extract (ARE) in Swiss albino mice against acute lethal total - body Electron beam irradiation. Swiss Albino mice were used for the assessment of radiation induced sickness and 30 day survival analysis. Survival studies were determined using the Kaplan-Meier survival curves. The maximum survival was observed in the experimental mice pretreated with 200 mg/kg.b.wt. of ARE which also reduced the radiation sickness characteristics. This dose was considered as an optimal dose for radioprotection. Treatment of mice with ARE before irradiation delayed the onset of mortality as compared with the untreated irradiated controls. Present findings demonstrate the potential of ARE in mitigating radiation-induced mortality, which may be attributed to its free radical scavenging and increased antioxidant potential

CFU-C populations in blood and bone marrow of dogs after lethal irradiation and allogeneic transfusion with cryopreserved blood mononuclear cells

International Nuclear Information System (INIS)

Nothdurft, W.; Fliedner, T.M.; Calvo, W.; Flad, H.-D.; Huget, R.; Koerbling, M.; Krumbacher-von Loringen, K; Ross, W.M.; Schnappauf, H.-P.; Steinbach, I.

1978-01-01

Colony forming units in agar (CFU-C) were assayed in both bone marrow and peripheral blood of dogs during haemopoietic recovery after lethal total-body irradiation (1200 R) and allogeneic transfusion of blood mononuclear cells (MNC) from histocompatible donors. MNC had been collected from the peripheral blood by continuous-flow centrifugation leucapheris and cryopreserved at -196 deg C until transfusion. Two groups of dogs were studied. Group 1 dogs (n = 12) were given between 0.39 and 2.76 x 10 9 MNC per kg body wt. Group 2 dogs (n = 14) were transfused with a similar number of MNC, ranging from 0.51 to 1.87 x 10 9 per kg body wt., but in addition underwent immuno-suppressive therapy with methotrexate. In group 1 dogs, there was a rather good correlation between the number of CFU-C in the regenerating bone marrow and the recovery of the peripheral blood granulocyte values. The regeneration of the CPU-C population in the bone marrow of methotrexate-treated dogs showed a somewhat more heterogeneous picture than in dogs of group 1 and in dogs that, in a previous study, were transfused with autologous MNC. The minimum time interval required for the reconstitution of peripheral blood CFU-C to normal levels was 2-4 weeks but usually took from 4-14 weeks. (author)

Studies on the mutagenic and cytogenetic effects of irradiated wheat in mice

International Nuclear Information System (INIS)

Reddy, P.P.; Reddi, O.S.; Ebenezer, D.N.; Naidu, N.V.; Goud, S.N.

1978-01-01

A series of experiments were conducted to test the mutagenic and cytogenetic potentials of freshly and stored irradiated wheat in mice. In the first series, the effects of feeding of CBA mice for 8 weeks with the diet containing 60% of wheat freshly irradiated ( 3 H/He mice were undertaken. Feeding of both freshly and stored irradiated wheat showed neither an increase in dominant lethals and chromosomal aberrations nor a reduction in germ cells. In another series, the reproductive performance of the CBA females fed stored irradiated (75 krad) wheat was investigated and it was observed that the average total number of litters and the litter size did not vary from those of the females fed unirradiated wheat. (author)

Stem and stromal cell reconstitution of lethally irradiated mice following transplantation of hematopoietic tissue from donors of various ages

International Nuclear Information System (INIS)

Schmidt, C.M.; Doran, G.A.; Crouse, D.A.; Sharp, J.G.

1987-01-01

If the limited life span of hematopoietic tissues in vitro is due to a finite proliferative capacity of individual stem cells, one might expect tissues of young donors to possess a greater proliferative capacity and to contain a larger population of primitive stem cells than those of older donors. To test this hypothesis, we used 12- and 8-day spleen colony formation (CFU-s) to assay more and less primitive stem cell subpopulations of three murine hematopoietic tissues: fetal liver (FL) and weanling (WBM) and adult (ABM) bone marrow. Subsequently, the same assays and a stromal cell assay were performed on the bone marrow from groups of lethally irradiated mice reconstituted with these tissues. Comparison of the CFU-s content of the donor tissues revealed that FL contained a significantly greater proportion of primitive stem cells as evidenced by a (Day 12):(Day 8) CFU-s ratio of 3.0 +/- 1.0 as compared to 0.9 +/- 0.1 for WBM and ABM. In addition, at 21 weeks post-transplantation the CFU-s/femur values of the FL reconstituted group were significantly greater than those of the ABM and WBM reconstituted groups. These results suggest that fetal hematopoietic tissue contains a greater proportion of primitive stem cells and has a greater proliferative potential than hematopoietic tissue from older donors. No differences were seen in stromal cell reconstitution of the three experimental groups. In all cases, assayable fibroblast colony forming cells (CFU-f) remained at 20-40% of control values, even at 21 weeks postreconstitution

Rad51 expression levels predict synthetic lethality and metastatic potential in high grade breast cancers

International Nuclear Information System (INIS)

Wiegmans, A.P.; Al-Ejeh, F.; Khanna, K.K.

2012-01-01

Among women with breast cancer, 30-40% will develop metastatic disease and only achieve an overall survival of less than 5 years. Despite new-targeted therapy, breast tumors that harbour similar histology or molecular phenotype differ in their response to treatment. To uncover potential new therapeutic targets and improve outcome, we performed data mining of cancer micro array databases. We found that high expression of the homologous recombination protein, RAD51, was significantly associated with high-grade breast cancer, aggressive subtypes and increased risk of metastasis. We confirmed using immunohistochemistry that RAD5 1 was highly expressed in metastatic tumours and high-grade triple negative, HER2+ and luminal-B tumours. This provided a rationale for targeting RAD5 1 in high-grade, therapy-resistant breast cancers. Here, we report for the first time preclinical evaluation of RAD5 1 as a therapeutic target. We found that, in-vitro high RAD5 expressing cell lines were resistant to PARP inhibitor while knockdown reversed this resistance. In-vivo, knockdown of RAD5 1 inhibited metastatic progression using a syngeneic breast cancer model and the seeding of human xenografts to distant sites, including brain and lung. Concurrent PARP inhibition reduced primary tumor growth and delayed metastasis supporting synthetic lethality in-vivo. Together these insights provide pre-clinical data demonstrating RAD5 1 as a new biomarker and potential therapeutic target against aggressive metastatic breast cancer. (author)

Effect of poly-A:U, dextran sulfate and yeast RNA on the bone marrow colony-forming ability in irradiated mice

International Nuclear Information System (INIS)

Chernyavskij, V.I.; Lysenko, A.I.; Kulakova, G.S.

1977-01-01

It has been shown, that poly-A:U, dextran sulfate and yeast RNA increased a number of endogenic colonies (COE) in the mouse spleen sublethally irradiated, as a result of, apparently, their mitogenic effect on proliferous COE. The preparations did not affect the number of exogenic colonies when introducting them together with transfer of syngenic cells of bone marrow, taken from the intact donors. Dextran sulfate increased 2.7 times the number of the endogenic colonies in the spleens of nonuniformly irradiated mice mainly due to the COE migration from protected bone marrow areas. The complex of poly-A:U and yest RNA in such experiment type were ineffective. One of the most important factors in the mechanism of the dextran sulfate adjuvant activity possibly is its ability to increase migration potencies of the stem blood-forming cells

Effect of electronic beam irradiation on last instar larvae of lasioderma serricorne fabricius

International Nuclear Information System (INIS)

Chen Yuntang; Guo Dongquan; Lu Xiaohua; Zhang Jianwei; Yang Baoan; Du Yueguang; Liu Jiangyu; Tian Zhanjun; Zhang Xiaoyan

2010-01-01

The electronic beam irradiation effects on the last instar larvae of cigarette beetle (Lasioderma serricorne Fabricius) in tobacco were studied, and the mortality in 42 days, lethal time, pupation rate, emergence rate and reproductive capacity after irradiation were measured. The results showed that the mortality increased with the increase of irradiation dosage, but the larvae did not dead immediately. The last instar larvae irradiated by the dosages higher than 480 Gy could prevent the development of larvae to adults. No new generation was found after 300 Gy treatment of the last instar larvae. So 300 Gy irradiation could be considered as a suitable dose to prevent the reproduction of cigarette beetle of the last instar larvae in the tobacco. (authors)

Influence of paternal 252Cf neutron exposure on abnormal sperm, embryonal lethality, and liver tumorigenesis in the F1 offspring of mice

International Nuclear Information System (INIS)

Watanabe, Hiromitsu; Takahashi, Tadateru; Lee, Juing-Yi

1996-01-01

Experiments were conducted to determine whether neutron-induced genetic damage in parental germline cells can lead to the development of cancer in the offspring. Seven-week-old C3H male mice were irradiated with 252 Cf neutrons at a dose of 0, 50, 100, or 200 cGy. Two weeks or 3 months after irradiation, the male mice were mated with virgin 9-week-old C57BL females. Two weeks after irradiation, the irradiated male mice showed an increased incidence of sperm abnormalities, which led to embryo lethalities in a dose-dependent manner when they were mated with unirradiated female mice. Furthermore, liver tumors in male offspring of male mice in the 50 cGy group were significantly increased in 19 of 44 (43.2%) animals, in clear contrast to the unirradiated group (1 of 31; 3.2%) (P 1 generation may be caused by genetic transmission of hepatoma-associated trait (s) induced by 252 Cf neutron irradiation. (author)

Lethal congenital contracture syndrome (LCCS) and other lethal arthrogryposes in Finland--an epidemiological study.

Science.gov (United States)

Pakkasjärvi, Niklas; Ritvanen, Annukka; Herva, Riitta; Peltonen, Leena; Kestilä, Marjo; Ignatius, Jaakko

2006-09-01

Arthrogryposis multiplex congenita is a heterogeneous group of disorders characterized by multiple contractures with an estimated frequency of 1 in 3,000 births. With improving diagnostic methods, increasing numbers of fetuses with arthrogryposis are found. The pathogenetic mechanisms are relatively well known but the epidemiology and genetics of the prenatally lethal forms of arthrogryposis are less well known. In this study we collected all cases of a multiple contractures diagnosed in Finland during 1987-2002 including live born infants, stillbirths, and terminated pregnancies. Ninety-two cases of 214 suffered intrauterine demise (68 selective pregnancy terminations and 24 stillbirths) and 58 died in infancy. In 141 out of these cases the diagnosis could be included within lethal arthrogryposes, with a prevalence of 1 in 6,985 (1.43/10,000) births. Of these, 59 had spinal cord pathology at autopsy and thus were of neurogenic origin. Thirty-nine cases had lethal congenital contracture syndrome (LCCS) clinically characterized by total immobility of the fetus at all ultrasound examinations (12 weeks or later), multiple joint contractures in both upper and lower limbs, hydrops, and fetal death before the 32nd week of pregnancy. LCCS is noted as a unique Finnish disorder with a prevalence of 1 in 25,250 (0.40/10,000) births and is a major cause of lethal arthrogryposis in Finland.

Effects of pre-irradiation on isogeneic and semi-isogeneic CFU growth

International Nuclear Information System (INIS)

Buurman, W.A.; Bruggen, I. Van.

1977-01-01

The genetic resistance to a parental bone marrow transplant as demonstrated, when transplantation were performed early after irradiation, failed to occur if the interval between irradiation and transplantation was increased to 4 days. A similar radiation induced weakening of genetic resistance to a parental bone marrow graft in spleen and bone marrow would be demonstrated in mice, which has been irradiated with a sublethal dose at 7 days prior to the lethal irradiation and transplantation. The pre-irradiation of the recipient with a sublethal dose induced an enhancement of the growth in spleen and bone marrow of isogenic transplanted CFU. The pre-irradiation of a single tibia also resulted in a significant weakening of the resistance in the spleen. The experiments with partial body pre-irradiation suggested a local effect of the pre-irradiation, but it could be shown that the enhanced CFU growth is not caused by an enhanced seeding of CFU in pre-irradiation bone marrow. The role of microenvironment in the phenomenon of genetic resistance is discussed. (author)

Increase of survival of x-irradiated mice by postirradiation injections of a splenic extract prepared from vaccine or endotoxin-treated syngeneic animals

Energy Technology Data Exchange (ETDEWEB)

Tsuneoka, K; Takagi, Y; Shikita, M [National Inst. of Radiological Sciences, Chiba (Japan)

1977-05-01

Spleens of mice which had been treated with E. coli endotoxin or typhoid-paratyphoid vaccine were extracted with isotonic saline. The extract was filtered through an asbestos filter and chromatographed on a Sephadex G-200 column. The fraction which was excluded at around 2.5-void volume (molecular weight, about 20,000) was significantly effective in increasing survival of animals when it was repeatedly injected in mice after x irradiation (600 R). The injection caused an increase of the weight of spleen of the animals with an increased number of endogenous spleen colonies. The result suggests that the life-saving effect of the spleen extract is based on its effect of stimulating repopulation of autochthonous hematopoietic cells in the x-irradiated animals. A similar splenic extract prepared from normal mice had an ambiguous effect on the survival of x-irradiated animals.

Prolonged bone marrow and skin allograft survival after pretransplant conditioning with cyclophosphamide and total lymphoid irradiation

International Nuclear Information System (INIS)

Kersey, J.H.; Kruger, J.; Song, C.; Kloster, B.

1980-01-01

Current studies were designed to provide long-term survival of allogeneic skin and bone marrow in mice preconditioned with various combinations of cyclophosphamide (CY) and/or total lymphoid irradiation (TLI). Long-term skin graft and bone marrow survival was obtained across the major histocompatibility barrier (BALB/c into C57BL/6) using pregrafting conditioning with either fractionated TLI or the combination of CY with a single dose of TLI. CY alone and a single dose of TLI alone were relatively ineffective as regrafting immunosuppressive combinations. Allogeneic bone marrow was required for long-term skin graft survival with either conditioning regimen. Allogeneic marrow transplantation resulted in somewhat more deaths than syngeneic transplantation with both CY + TLI and fractionated TLI

Heterogeneous response to X-ray and ultraviolet light irradiations of cultured skin fibroblasts in two families with Gardner's Syndrome

International Nuclear Information System (INIS)

Kinsella, T.J.; Little, J.B.; Nove, J.; Weichselbaum, R.R.; Li, F.P.; Meyer, R.J.; Marchetto, D.J.; Patterson, W.B.

1982-01-01

A heterogeneous response to X-ray and far UV (254 nm) light irradiations was found in cultured skin fibroblast lines from 2 separate families with Gardner's syndrome. When compared to 2 normal control cultures and cultures from 2 patients with nonfamilial colon cancer, cultures from 4 clinically affected members of family 1 showed increased sensitivity to the lethal effects of both X-ray and UV light irradiations. These cells also showed a delayed pattern of X-ray potentially lethal damage repair (PLDR) and absent UV PLDR. In contrast, cultures from 3 members of family 2 (2 of whom were clinically affected) showed a normal response of survival and PLDR to both X-ray and UV light irradiations. Thus increased sensitivity of cultured skin fibroblasts to X-ray and UV light irradiations was not a consistent in vitro finding in patients with Gardner's syndrome. However, in families with Gardner's syndrome who demonstrate in vitro radiosensitivity, additional studies are needed to assess the usefulness of these techniques in detecting affected individuals prior to the development of colon carcinoma and other manifestations

Regulation for the radiological safety in the design and operation of industrial Gamma irradiators in Egypt

International Nuclear Information System (INIS)

Abdel-Ghani, A.H.; Hussein, A.Z.

2000-01-01

Large gamma irradiators present a high potential irradiation hazard since the amount of radioactivity is of the order of P Bq and a very high dose rate are produced during irradiation. Nevertheless, individuals may accidentally receive a lethal dose within minutes or seconds, due to failure of radiation control and safety systems. The competent authority (NCNSRC) is concerned with the impact of all radiation activities on workers as well as public health and safety. Radiation control of such large irradiation facilities can be achieved by means of strict regulatory procedures during construction, licensing, operation, inspection, maintenance and decommissioning

Measurement of oxygen enhancement ratio for sub-lethal region using saccharomyces cerevisiae

International Nuclear Information System (INIS)

Nairy, Rajesha K.; Anjaria, K.B.; Bhat, Nagesh N.; Chaurasia, Rajesh K.; Balakrishnan, Sreedevi; Yerol, Narayana

2013-01-01

Oxygen is one of the best known modifiers of radiation sensitivity and the biological effects is greater in the presence of oxygen, and significant modifying effect will be observed only for low LET radiations. The reduced oxygen availability is sensed which trigger homeostatic responses, which impact on virtually all areas of biology and medicine. Failure to achieve complete response following radiotherapy of large tumors is attributed to the presence of radio-resistant hypoxic cells, therefore clarifying the mechanism of the oxygen effect is important. In the present study, a mutant type diploid yeast strain, Saccharomyces cerevisiae D7 was used to study Oxygen Enhancement Ratio (OER) using 60 Co gamma radiation. Cells were washed thrice by centrifugation (2000 g for 5 min) and re-suspended to a cell concentration of 1x108 cells mL-1 in a sterile polypropylene vial for irradiation (sub-lethal dose range, 0-100 Gy). Hypoxic conditions were achieved by incubating the cells in airtight vials at 30℃ for 30 min prior to irradiation. The gene conversion and back mutation analysis were carried out according to the standard protocol. Gene conversion is the radio-sensitive biological endpoint, that can be studied in Saccharomyces cerevisiae D7 yeast cells at trp locus in tryptophan (Trp- medium) deficient medium. The dose response relation at euoxic and hypoxic condition in sub-lethal doses are found to be linear and is represented by Y (Euoxic) = (6.54±0.102) D with R2=0.999 and for hypoxic condition Y(Hypoxic) = (3.346±0.033) D with R2=0.996. The OER can be calculated by dividing the euoxic slope with hypoxic slope, and is 1.95. Back mutation, which is a result of reversion of Isoleucine auxotrophs to prototrophs gives very good information at sub-lethal doses. The dose response relation between back mutated cells and radiation doses at Euoxic and hypoxic condition can be represented as Y(Euoxic) = (2.85±0.126) D with R2= 0.976 and for hypoxic condition Y

Study of acute ecotoxicity of Resveratrol in Daphnia similis irradiated and non-irradiated

International Nuclear Information System (INIS)

Ormenio, Matheus B.; Mazieiro, Joana S.; Rogero, Sizue O.; Rogero, José R. Rogero

2017-01-01

Resveratrol is synthesized by a wide variety of plants in response to ultraviolet (UV) radiation or action of certain pathogens. It is a compound with ability to protect cells from free radicals, responsible for the natural process of cellular aging. It is known that resveratrol has a radiomodifying effect, in addition to the antioxidant potential, anti-inflammatory, against cardiovascular diseases. The increasing use of resveratrol as a function of biological activities has led to concern about toxicity. In the ecotoxicological area, acute ecotoxicity tests are performed on aquatic organisms that lethal effects of certain substances and / or environmental samples. These tests are important in providing critical information for the development and adoption of criteria for improvement environmental quality. In these tests Cladoceras are widely used as test organisms due to their extreme susceptibility to toxicants in the environment and because they are easy to handle in the laboratory. In this study, it was used Daphnia similis to verify the toxic effect of resveratrol on this non-irradiated organism and irradiated with gamma radiation. First, toxicity studies of resveratrol and gamma Daphnia similis, where the lethal dose (LD50) of the 585.43 Gy radiation was determined and the EC50 concentration of resveratrol that causes immobility in 50% of the organisms in the assay, of 6.08 μM. Based on these data, the study will be continued to assess the toxic effect of radiation on organisms that have been exposed prior to resveratrol, i.e, to verify the radiomodifying effect of resveratrol

Changes in electrolytes and blood gas after transfusion of irradiated MAP

International Nuclear Information System (INIS)

Miyao, Hideki; Katayama, Akinori; Okamoto, Yumi; Koyama, Kaoru; Kawasaki, Jun; Kawazoe, Taro

2001-01-01

This study was undertaken to investigate the changes in recipient serum electrolytes and arterial blood gas after irradiated blood transfusion. We measured electrolytes and arterial blood gas before and after the transfusion during elective surgery in 55 patients. The mean blood loss was 1,477 g and the mean transfused blood unit of irradiated Mannitol-Adenine-Phosphate (MAP) was 5.9 units. Potassium concentration increased from 3.8 to 4.2 mEq·l -1 . A total of 187 units, which had been stored for 12.3±3.5 days after donation and for 5.1±3.8 days after irradiation, was used. There was a significant correlation between the storage period from the day of irradiation and the potassium concentration of the supernatant (r=0.56, p<0.0001). This study recommends that a safe transfusion rate of irradiated blood should be determined because the high potassium concentration of irradiated blood may lead to lethal complications in case of rapid transfusion. (author)

Lethal and mutagenic effects of radiation and chemicals on cultured fish cells derived the erythrophoroma of goldfish (Carassius auratus)

Energy Technology Data Exchange (ETDEWEB)

Mitani, H. (Tokyo Univ. (Japan). Inst. of Zoology)

1983-01-01

GEM 199 cells derived from an eryhtrophoroma of goldfish (Carassius auratus), which had a high plating efficiency, were used to investigate the lethal and mutational effects of radiations (UV and ..gamma..-rays) and chemicals (4NQO and MNNG). The cells were more resistant to rays than mammalian cells and CAF-MM1 cells derived from the normal fin tissue of goldfish. They were also more resistant to UV-irradiation than CAF-MM1 cells. Photoreactivation after UV-irradiation was present in GEM 199 cells for both survival and mutation. The initial shoulder of the survival curve of UV-irradiated cells was reduced greatly by caffeine, suggesting a high activity of the post-replication repair. The spontaneous mutation frequency to ouabain resistance was 1-5x10/sup -6/ clones per viable cell. MNNG was effective in inducing ouabain-resistant mutation, while 4NQO and ..gamma..-rays did not induce mutation.

Chronic Exposure of Corals to Fine Sediments: Lethal and Sub-Lethal Impacts

Science.gov (United States)

Flores, Florita; Hoogenboom, Mia O.; Smith, Luke D.; Cooper, Timothy F.; Abrego, David; Negri, Andrew P.

2012-01-01

Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS) for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata) more than the upright branching species (Acropora millepora). The lowest sediment treatments that caused full colony mortality were 30 mg l−1 TSS (25 mg cm−2 day−1) for M. aequituberculata and 100 mg l−1 TSS (83 mg cm−2 day−1) for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue. PMID:22662225

Chronic exposure of corals to fine sediments: lethal and sub-lethal impacts.

Directory of Open Access Journals (Sweden)

Florita Flores

Full Text Available Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata more than the upright branching species (Acropora millepora. The lowest sediment treatments that caused full colony mortality were 30 mg l(-1 TSS (25 mg cm(-2 day(-1 for M. aequituberculata and 100 mg l(-1 TSS (83 mg cm(-2 day(-1 for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue.

Studies on a possible using of penicillin and specific globulin for treatment of Siberia ulcer infection in irradiated animals

International Nuclear Information System (INIS)

Strel'nikov, V.A.; Mal'tsev, V.N.

1975-01-01

The efficiency of anti-anthracic globulin and penicillin for treating infectious anthrax was compared in experiments on 160 guinea pigs and 400 white mice irradiated with sub-lethal doses of cobalt-60 gamma rays. It was found that penicillin retained its effectiveness in the irradiated animals whereas anti-anthracic globulin lost much of its therapeutic efficiency. (auth.)

Toxoplasma gondii gamma irradiation using Co-60

International Nuclear Information System (INIS)

Serra-Freire, Nicolau Maues

1996-01-01

The use of nuclear power through radiation for the destruction of microorganisms which cause food deterioration, infections and toxicosis, is specifically for peaceful purposes. Toxoplasma gondii is a protozoa responsible for illnesses in humans and animals. One of the most common ways of transmission is through raw or poorly cooked meat. There is little information on the resistance of T. gondii to radiation. The objective of this research is to determine the Minimum Lethal Dose (MLD) of gamma radiation for those microorganisms. Suspensions of T. gondii containing approximately one million taquizoites/ml were irradiated with doses between up 0,01 up to 0,15 kGy (Kilogray) and inoculated to mice. The surviving T. gondii were re-irradiated with 0,01 up to 0,16 kGy. The irradiated protozoa were totally destroyed with a 0,15 kGy dose (MLD). Taquizoites issued from live protozoa of 0,14 kGy also were completely destroyed with dose of 0,15 kGy. No increase in resistance was observed regarding the non irradiated protozoa. (author)

Induction of the SOS system in Escherichia coli after UVA (320 - 400 nm) irradiation

International Nuclear Information System (INIS)

Batbyamba, G.; Drasil, V.

1988-01-01

Induction of the SOS repair system in E. coli caused by broad-band (320 - 400 nm) UVA radiation and an oxygen effect in this induction were studied using the sfiA::lacZ operon fusion. Moreover, an oxygen effect on the broad-band UVA radiation-induced cell killing was studied. The experiments indicate that: (1) Broad-band UVA light can produce lethal damage to cells as well as DNA damage able to generate an SOS-inducing signal. This damage is O 2 -dependent to a significant extent: SOSIP (O 2 )/ SOSIP (Ar) = 1.61 and OER = 1.96; (2) After UVA irradiation the SOS induction factor increases monotonously in the time interval longer than 4 h indicating that the SOS-inducing DNA damage caused by UVA irradiation has a 'long-lived' character; (3) Oxic and hypoxic incubation following UVA irradiation carried out under aerobic and anaerobic conditions resulted in a strong oxygen effect: SOSIP(O 2 )/SOSIP(Ar) ∼ 5. On the basis of these results and literary data it was concluded that one of the main toxic photoproducts formed as a result of UVA irradiation of the cells in a culture medium might be hydrogen peroxide (H 2 O 2 ). H 2 O 2 decays gradually during post-irradiation incubation and yields reactive radical species, mainly OH radical, that result in a formation of SOS-inducing DNA damages and contribute to cell lethality, and prolonged SOS induction. (author)

Extra lethal damage due to residual incompletely repaired sublethal damage in hyperfractionated and continuous radiation treatment

Energy Technology Data Exchange (ETDEWEB)

Chen, J.; van de Geijn, J.; Goffman, T. (ROB, DCT, NCI, NIH, Bethesda, Maryland 20892 (US))

1991-05-01

In the conventional linear--quadratic model of single-dose response, the {alpha} and {beta} terms reflect lethal damage created {ital during} the delivery of a dose, from two different presumed molecular processes, one linear with dose, the other quadratic. With the conventional one-fraction-per-day (or less) regimens, the sublethal damage (SLD), presumably repairing exponentially over time, is essentially completely fixed by the time of the next dose of radiation. If this assumption is true, the effects of subsequent fractions of radiation should be independent, that is, there should be little, if any, reversible damage left from previous fractions, at the time of the next dose. For multiple daily fractions, or for the limiting case, continuous radiation, this simplification may overlook damaged cells that have had insufficient time for repair. A generalized method is presented for accounting for extra lethal damage (ELD) arising from such residual SLD for hyperfractionation and continuous irradiation schemes. It may help to predict differences in toxicity and tumor control, if any, obtained with unconventional'' treatment regimens. A key element in the present model is the finite size and the dynamic character of the pool of sublethal damage. Besides creating the usual linear and quadratic components of lethal damage, each new fraction converts a certain fraction of the existing SLD into ELD, and creates some new SLD.

Extra lethal damage due to residual incompletely repaired sublethal damage in hyperfractionated and continuous radiation treatment

International Nuclear Information System (INIS)

Chen, J.; van de Geijn, J.; Goffman, T.

1991-01-01

In the conventional linear--quadratic model of single-dose response, the α and β terms reflect lethal damage created during the delivery of a dose, from two different presumed molecular processes, one linear with dose, the other quadratic. With the conventional one-fraction-per-day (or less) regimens, the sublethal damage (SLD), presumably repairing exponentially over time, is essentially completely fixed by the time of the next dose of radiation. If this assumption is true, the effects of subsequent fractions of radiation should be independent, that is, there should be little, if any, reversible damage left from previous fractions, at the time of the next dose. For multiple daily fractions, or for the limiting case, continuous radiation, this simplification may overlook damaged cells that have had insufficient time for repair. A generalized method is presented for accounting for extra lethal damage (ELD) arising from such residual SLD for hyperfractionation and continuous irradiation schemes. It may help to predict differences in toxicity and tumor control, if any, obtained with ''unconventional'' treatment regimens. A key element in the present model is the finite size and the dynamic character of the pool of sublethal damage. Besides creating the usual linear and quadratic components of lethal damage, each new fraction converts a certain fraction of the existing SLD into ELD, and creates some new SLD

Effect of gamma irradiation on morphology of leaf and shoot apex of ginger, turmeric and mango-ginger

International Nuclear Information System (INIS)

Raju, E.C.; Patel, J.D.; Shah, J.J.

1980-01-01

Effect of 2, 5, 10, 20 and 30 kR gamma irradiation on morphology and growth of ginger (Zingiber officinale Rosc.), Turmeric (Curcuma domestica Valet) and mango-ginger (Curcuma amada Roxb), and shoot apical organisation in ginger was studied. Higher doses (20 and 30 kR) of radiation proved to be lethal. Morphological aberrations in foliage leaves are reported. Irradiated shoot apices appear histologically inert. (auth.)

Effect of gamma irradiation on morphology of leaf and shoot apex of ginger, turmeric and mango-ginger

Energy Technology Data Exchange (ETDEWEB)

Raju, E C; Patel, J D; Shah, J J [Sardar Patel Univ., Vallabh Vidyanagar (India). Dept. of Biosciences

1980-06-01

Effect of 2, 5, 10, 20 and 30 kR gamma irradiation on morphology and growth of ginger (Zingiber officinale Rosc.), Turmeric (Curcuma domestica Valet) and mango-ginger (Curcuma amada Roxb), and shoot apical organisation in ginger was studied. Higher doses (20 and 30 kR) of radiation proved to be lethal. Morphological aberrations in foliage leaves are reported. Irradiated shoot apices appear histologically inert.

Immunologic parameters of ultraviolet carcinogenesis

International Nuclear Information System (INIS)

Kripke, M.L.; Fisher, M.S.

1976-01-01

Skin tumors induced in mice by uv light are usually immunologically rejected by normal syngeneic recipients. We evaluated, the immune status of primary hosts against these highly antigenic tumors immediately after surgical removal of the primary tumor. All primary hosts were susceptible to challenge with their autochthonous tumors, though most of these were rejected by untreated control mice. Primary hosts were also susceptible to challenge with isografts of antigenically dissimilar uv-induced neoplasms. The susceptibility of the primary hosts to tumor challenge was probably induced by chronic exposure to uv light, since uv-irradiated non-tumor-bearing mice were also susceptible to challenge with these tumors. Although uv-treated mice were unable to reject these syngeneic tumors, they could reject skin and tumor allografts. Further, uv irradiation did not interfere with the second-set rejection of syngeneic uv-induced tumors in mice that were specifically immunized before uv treatment

An oral Hemokine™, α-methylhydrocinnamate, enhances myeloid and neutrophil recovery following irradiation in vivo

Science.gov (United States)

Faller, Douglas V.; Castaneda, Serguei A.; Zhou, Daohong; Vedamony, Merriline; Newburger, Peter E.; White, Gary L.; Kosanke, Stanley; Plett, P. Artur; Orschell, Christie M.; Boosalis, Michael S.; Perrine, Susan P.

2017-01-01

An oral therapeutic which reduces duration of cytopenias and is active following accidental radiation exposures is an unmet need in radiation countermeasures. Alpha methylhydrocinnamate (ST7) prolongs STAT-5 phosphorylation, reduces growth-factor dependency of multi-lineage cell lines, and stimulates erythropoiesis. Here, ST7 and its isomers were studied for their effects on myeloid progenitors and hematopoietic stem cells (HSCs) following radiation, in nonhuman primates, and murine irradiation models. Addition of ST7 or ST7-S increased CFU-GM production by 1.7-fold (p200/mm3 and neutropenia recovered in 6 days with ST7 treatment and 18 days in controls (p<0.05). In lethally-irradiated mice, marrow pathology at 15 days was hypocellular (10% cellularity) in controls, but normal (55–75% cellularity) with complete neutrophil maturation with ST7-S treatment. Following lethal irradiation, ST7, given orally for 4 days, reduced mortality, with 30% survival in ST7-animals vs 8% in controls, (p<0.05). Collectively, the studies indicate that ST7 and ST7-S enhance myeloid recovery post-radiation and merit further evaluation to accelerate hematologic recovery in conditions of radiation-related and other marrow hypoplasias. PMID:27888688

In vitro study of the influence of alpha particles irradiation on the pre-neoplastic transformation of rat trachea epithelial cells

International Nuclear Information System (INIS)

Kugel, C.

2001-12-01

Intern contamination by actinide oxide inhalation is potentially one health hazard during the nuclear fuel fabrication process. The aerosol particles can induce pulmonary lesions, such as epithelial cancers in particular. Their toxicity is mainly due to radiotoxicity of α irradiation. The aim of this work was to contribute, by an in vitro model, to the study of the apparition of pre-neoplastic states on epithelial cells after high LET irradiation. Primary cultures of rat tracheal epithelial cells were used. Two rat strain cells, SD TR for Sprague Dawley rats and WF TR for Wistar Furth I Fischer F344 rats, were compared after exposure to a dose range from 0 to 5 Gy. Reproductive cell death, i.e. senescent death, seems to be the main lethal way induced by α and γ irradiations. The nuclear volume of WF TR cells is higher than that of SD TR ones, explaining the higher α radiation-induced lethality of these cells. These WF TR cells are also much sensitive to dose rate and α particles energy. In the same manner, pre-neoplastic transformation rate of the cells seems to depend on the physical parameters of irradiation. But, it mainly varies as a function of cell radiosensitivity, that means cell death. In fact, the transformation rate of sensitive WF TR cells is lower than that of SD TR ones. In term of transformation for SD TR cells, dose-effect relationship fits to a linear and infra linear function after α irradiation, whereas the curve fits to linear and quadratic function after γ irradiation. The Relative Biological Efficiency (RBE) of α particles for lethality and pre-neoplastic transformation were determined for several levels of dose. A constant value of about 3 was found for RBE of lethality whatever the α dose. By contrast, the RBE of transformation has a value of about 10 up to 0.5 Gy and gradually decreases at higher doses to reach a value of 1 at 5 Gy. Similar shapes of dose-effect relationship can be observed for malignant lung tumour induction after

Therapeutic effects of the joint administration of magnesium aspartate and adenosine monophosphate in gamma-irradiated mice

International Nuclear Information System (INIS)

Pospisil, M.; Netikova, J.; Pipalova, I.; Kozubik, A.

1990-01-01

The joint administration of magnesium aspartate and adenosine monophosphate, injected on days 1 to 4 post radiation, has been found to exert stimulatory effects on the recovery of hemopoietic functions in sublethally gamma-irradiated mice. These therapeutical effects were enhanced in animals protected by peroral administration of cystamine. The treatment scheme used did not modify survival of lethally irradiated mice. The therapeutic effects of magnesium aspartate and adenosine monophosphate in sublethally irradiated mice are explained by the stimulatory action of these drugs on the cell adenylate cyclase system, which influences the erythropoietic functions. (author)

Cellular therapy without cells: extracellular vesicles promote activation of stem cells after irradiation

International Nuclear Information System (INIS)

Lange, C.

2016-01-01

Mesenchymal stromal cells from the bone marrow (MSC) have been shown to be effective in several cell therapeutic treatments. However, MSC accumulate in lungs after i.v. injection. How do MSC transfer their potential to organs with therapeutic need? We show that released extracellular vesicles (EV) might be playing an active role in this transfer. EV were isolated from MSC supernatant and characterized with flow cytometry, proteomics and next generation sequencing. Our data showed the transfer of RNAs, clustering into several protective gene groups. Besides, we repeatedly detected genomic DNA on vesicles. Using a plant - derived detector gene we showed horizontal DNA transfer via EV. Furthermore, we showed that EV were able to salvage stem/progenitor cells in vitro from radiation suppression. Three selected proteins from proteomics data were examined for stem cell protection after irradiation. EV derived from down-regulated producer MSC showed a substantial loss of protection in irradiated stem cells supporting their relevance for stem cell protection. Finally, we showed that EV after i.v. injection into lethally irradiated animals colocalize within 2-4 hours with hematopoietic stem cells in the bone marrow giving hint to direct protection of stem cells by EV. In conclusion, EV derived from bone marrow MSC were able to transfer several cargo compounds leading potentially to change of the genetic properties. Importantly, EV protect irradiated hematopoietic stem cells, stimulate their recovery and proliferation and rescue lethally irradiated animals long-term. Thus, EV might be an alternative for future cell therapeutic treatment particularly in radiation-based events. (author)

Implantation of GL261 neurospheres into C57/BL6 mice: a more reliable syngeneic graft model for research on glioma-initiating cells.

Science.gov (United States)

Yi, Liang; Zhou, Chun; Wang, Bing; Chen, Tunan; Xu, Minhui; Xu, Lunshan; Feng, Hua

2013-08-01

Recent studies have demonstrated that inflammatory cells and inflammatory mediators are indispensable components of the tumor-initiating cell (TIC) niche and regulate the malignant behavior of TICs. However, conventional animal models for glioma-initiating cell (GIC) studies are based on the implantation of GICs from human glioblastoma (GBM) into immunodeficient mice without the regulation of immune system. Whether animal models can mimic the cellular microenvironment of malignancy and evaluate the biological features of GICs accurately is unclear. Here, we detected the biological features of neurosphere-like tumor cells derived from the murine GBM cell line GL261 (GL261-NS) and from primary human GBM (PGBM-NS) in vitro, injected GL261-NS into syngeneic C57/BL6 mouse brain and injected PGBM-NS into NOD/SCID mouse brain, respectively. The tumorigenic characteristics of the two different orthotopic transplantation models were analyzed and the histological discrepancy between grafts and human primary GBM was compared. We found that GICs enriched in GL261-NS, GL261-NS and PGBM-NS exhibited increased GIC potential and enhanced chemoresistance in vitro. GL261-NS was significantly more aggressive compared to GL261 adhesive cells (GL261-AC) in vivo and the enhanced aggression was more significant in syngeneic mice compared to immunodeficient mice. The discrepancy of tumorigenicity between GL261-NS and GL261-AC in C57/BL6 mice was also larger compared to that between PGBM-NS and PGBM-AC in immunodeficient mice. Syngrafts derived from GL261-NS in C57/BL6 mice corresponded to the human GBM histologically better, compared with xenografts derived from PGBM-NS in NOD/SCID mice, which lack inflammatory cells and inflammatory mediators. We conclude that the inflammatory niche is involved in the tumorigenicity of GICs and implantation of GL261-NS into C57/BL6 mice is a more reliable syngeneic graft model for in vivo study on GICs relative to the immunodeficiency model.

Effects of gamma irradiation on fresh and dry weights of plant parts in Physalis L

International Nuclear Information System (INIS)

Raghava, R.P.; Raghava, Nisha

1989-01-01

20 KR irradiations on Physalis peruviana L. and P. angulta L. seem to be the best dose for plant growth. 40 and 50 KR doses were inhibitory to both, and 50 KR was found to be almost lethal (LD 50 ). (author). 14 refs

Dynamics of genetic processes in chronically irradiated populations of small mammals

International Nuclear Information System (INIS)

Ryabokon', N.I.; Goncharova, R.I.; Smolich, I.I.; Kapitanova, N.P.; Nikitchenko, N.V.

2000-01-01

The distinctive features of dynamics of mutagenesis in mammalian populations under chronic low-intensive irradiation were first revealed. The main of them is gradual increase in mutability in somatic cells and embryonal lethality during series of irradiated generations of animals (bank vole - Clethrionomys glareolus). The data obtained strongly suggest that there are oppositely directed processes in natural populations after irradiation of more than 20 generations of animals: on the one hand, accumulation of mutations (genetic load of populations) and pre-mutation events which increase genome instability of germ and somatic cells in consecutive generations of animals, and on the other, formation of genetic radio adaptation through better functioning protection systems. In this period of micro evolution in chronically irradiated populations, the frequencies of genetic damages could be higher if the radiation adaptation doesn't form. (authors)

Extracellular hydrogen peroxide produced under irradiation as the most important factor in the lethality of gamma-irradiated Paramecium tetraurelia

International Nuclear Information System (INIS)

Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Dupouy, D.; Planel, H.

1982-01-01

It has been shown that the surviving fraction of γ-irradiated paramecia is correlated with the residual H 2 O 2 concentration in the extracellular medium which is strongly dependent on the bacterial concentration, that is, on the enzyme content in the culture medium. (author)

Monoclonal antibodies reactive with common tumor antigens on UV-induced tumors also react with hyperplastic UV-irradiated skin

International Nuclear Information System (INIS)

Spellman, C.W.; Beauchamp, D.A.

1986-01-01

Most murine skin tumors induced by ultraviolet light (UVB, 280-340 nm) can be successfully transplanted only into syngeneic hosts that have received subcarcinogenic doses of UVB. The tumor susceptible state is long-lived and mediated by T suppressor cells that control effector responses against common antigens on UV-induced tumors. Because antigen specific suppression arises prior to the appearance of a tumor, questions arise about the source of the original antigen. They have previously reported transplantation studies indicating that UV-irradiated skin is antigenically cross-reactive with UV-induced tumors. They now report on flow cytometry analyses showing that a series of MoAb reactive with common antigens expressed by UV-induced tumors are also reactive on cells from UV-irradiated skin. Various antigens appear at different times in the UV irradiation scheme, and some persist while others are transient. They speculate that the common antigens detected may be the ones to which functional suppression is directed. If true, these results suggest that successful tumors need not escape host defenses to emerge. Rather, tumors may arise and grow progressively if they express antigens that cross-react with specificities to which the host has previously mounted a suppressive response

Genotoxicity test of irradiated foods

International Nuclear Information System (INIS)

Tanaka, Noriho

2004-01-01

Safety tests of radiation irradiated foods started as early as from 1967 in Japan and genotoxicity tests in the Hatano Res. Inst., from 1977. The latter is unique in the world and is reviewed in this paper. Tests included those for the initial injury of DNA, mutagenicity, chromosomal aberration and transformation with use of bacteria, cultured mammalian cells and animals (for chromosomal aberration, micronucleus formation and dominant lethality). Foods tested hitherto were onion, rice, wheat and flour, Vienna sausage, fish sausage (kamaboko), mandarian orange, potato, black pepper and red capsicum, of which extract or powder was subjected to the test. Irradiation doses and its purposes were 0.15-6 kGy γ-ray ( 60 Co) or electron beam by the accelerator (only for the orange), and suppression of germination, pesticide action or sterilization, respectively. Genotoxicity of all foods under tested conditions is shown negative. (N.I.)

Differentiation of strains of yellow fever virus in γ-irradiated mice

International Nuclear Information System (INIS)

Fitzgeorge, R.; Bradish, C.J.

1980-01-01

The mouse sensitized by optimal, sub-lethal γ-irradiation has been used for the differentiation of strains of yellow fever virus and for the resolution of their immunogenicity and pathogenicity as distinct characteristics. For different strains of yellow fever virus, the patterns of antibody-synthesis, regulatory immunity (pre-challenge) and protective immunity (post-challenge) are differentially sensitive to γ-irradiation. These critical differentiations of strains of yellow fever virus in γ-irradiated mice have been compared with those shown in normal athymic and immature mice in order to elucidate the range of quantifiable in vivo characteristics and the course of the virus-host interaction. This is discussed as a basis for the comparisons of the responses of model and principal hosts to vaccines and pathogens. (author)

Induced variation in potato dry rot fusarium roseum by ultraviolet irradiation

International Nuclear Information System (INIS)

Lee, C.U.

1979-01-01

Variations were readily induced in Fusarium roseum isolated from decayed potato tubers by subjecting its conidia to ultraviolet irradiation. The dosage that resulted in complete absence of developing colonies in five minutes of irradiation did not cause the mortality of conidia for the initial one minute. Eighty eight precent of conidia were killed in three minutes. Approximately 90% of the conidia showed resistance to lethality for the initial two minutes whereas 10% began to show resistance after three minutes of the irradiation. The maximum 42% of color variation was obtained among the surviving conidia. Varients in both decreased and increased pathogenicity were induced in 8% among the color variants. Variations occurred in such other characteristics as growth rate, rigidity of mycelium, and conidia formation. (author)

Toxicity of some insecticides to F1 progeny of the cotton leaf worm; Spodoptera littoralis (Boisd) gamma irradiated as parental pupae (Lepidoptera: Noctuidae)

International Nuclear Information System (INIS)

El-Shall, S.S.A.; Hazaa, M.A.M.; Alm El-Din, M.M.S.

2006-01-01

The response of the F1 Progeny of Cotton Leaf worm; Spodoptera littoralis Boisd, (from male irradiated as parental pupae with 0, 50, 100 and 150 Gy of gamma irradiation) to Silicron, Atabron and Catabroun were studied. The lethal concentration doses of insecticides that kill 10,50 and 90 % of population (LC 10 , LC 50 and LC 90 ); The lethal time that kill 50% of population (LT 50 ) and the Tolerance Ratio(T.R) to the different previous insecticides were employed as parameters for measuring the response of irradiated and un-irradiated progeny. The results indicated that, the dose of irradiation and time post insecticides application had a great role in alter the response of F1 progeny of S. littoralis to the different-insecticides. Also, gamma irradiation increased the toxicity of Silicron at 2 and 4 days post insecticide treatments. By time elapsing after insecticide application the irradiated larvae became virtually the same degree of susceptibility as compared to non-irradiated ones. As well, 50 Gy slightly alter the toxicity of Atabron, while population irradiated with 100 and 150 Gy showed a high level of susceptibility to Atabron at 22 and 26 days post insecticide treatments as compared to un-irradiated population. In addition, the toxicity of Catabroun increased in case of irradiated population at most of interval time post insecticide treatments as compared to un-irradiated ones. Furthermore, a Comparison was made and discussed between the susceptibility of irradiated population only, population treated with insecticides only and population treated with both insecticides and radiation by using the standard parameter LT 50

Extracellular hydrogen peroxide produced under irradiation as the most important factor in the lethality of gamma-irradiated Paramecium tetraurelia

Energy Technology Data Exchange (ETDEWEB)

Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Dupouy, D.; Planel, H. (Laboratoire de Biologie Medicale, 31 - Toulouse (France))

1982-02-01

It has been shown that the surviving fraction of ..gamma..-irradiated paramecia is correlated with the residual H/sub 2/O/sub 2/ concentration in the extracellular medium which is strongly dependent on the bacterial concentration, that is, on the enzyme content in the culture medium.

Mining of lethal recessive genetic variation in Danish cattle

DEFF Research Database (Denmark)

Das, Ashutosh

2015-01-01

in fertility. The primary objective of this PhD projekt was to identify recessive lethal gentic variants in the main Danish dairy cattle breed. Holstein-Friesian utilzing next generation sequencing (NGS) data. This study shows a potential for the use of the NGS-based reverse genetic approach in identifying...... lethal or semi-lethal recessive gentic variation...

Is phenytoin contraindicated in patients receiving cranial irradiation?

Energy Technology Data Exchange (ETDEWEB)

Borg, M.F. [Royal Adelaide Hospital, SA (Australia); Probert, J.C. [Auckland Hospital, Auckland (New Zealand). Dept. of Radiation Oncology; Zwi, L.J. [Auckland Univ. (New Zealand). Dept. of Medicine and Surgery

1995-02-01

Three recent publications have reported the development of erythema multiforme and Stevens-Johnson syndrome in patients receiving cranial irradiation and sodium phenytoin. Some authors have recommended that patients receiving whole brain radiation therapy and who have had seizures should not be prescribed phenytoin but an alternative anticonvulsant. This article reviews the current literature pertaining to the development of this potentially lethal complication in patients receiving whole brain radiation and phenytoin, with reference to the single recorded case of Stevens-Johnson syndrome in a patient receiving cranial irradiation and phenytoin in Auckland, New Zealand. While the clinical picture in the 16 patients reported in the literature and the current case report differed from the classical form of erythema multiforme, a similar pattern of presentation and outcome appeared in all patients reviewed, suggesting that the combination of phenytoin, cranial irradiation and the gradual reduction of concomitant steroids seem to lead to the development of erythema multiforme and/or Stevens-Johnson syndrome. The data presented, although sparse, suggest that phenytoin should not be prescribed in patients receiving cranial irradiation. 21 refs., 2 tabs., 3 figs.

Is phenytoin contraindicated in patients receiving cranial irradiation?

International Nuclear Information System (INIS)

Borg, M.F.; Probert, J.C.; Zwi, L.J.

1995-01-01

Three recent publications have reported the development of erythema multiforme and Stevens-Johnson syndrome in patients receiving cranial irradiation and sodium phenytoin. Some authors have recommended that patients receiving whole brain radiation therapy and who have had seizures should not be prescribed phenytoin but an alternative anticonvulsant. This article reviews the current literature pertaining to the development of this potentially lethal complication in patients receiving whole brain radiation and phenytoin, with reference to the single recorded case of Stevens-Johnson syndrome in a patient receiving cranial irradiation and phenytoin in Auckland, New Zealand. While the clinical picture in the 16 patients reported in the literature and the current case report differed from the classical form of erythema multiforme, a similar pattern of presentation and outcome appeared in all patients reviewed, suggesting that the combination of phenytoin, cranial irradiation and the gradual reduction of concomitant steroids seem to lead to the development of erythema multiforme and/or Stevens-Johnson syndrome. The data presented, although sparse, suggest that phenytoin should not be prescribed in patients receiving cranial irradiation. 21 refs., 2 tabs., 3 figs

Effect of sulfhydryls on potentiation of radiation-induced cell lethality by substituted anthraquinones

International Nuclear Information System (INIS)

Kimler, B.F.

1984-01-01

The effects of various substituted anthraquinones (SAQ's) and Adriamycin (ADR) were investigated in cultured Chinese hamster V79 cells. These drugs cause a potentiation of radiation-induced cell lethality, albeit by different mechanisms. One possibility is that these components operate through the production of free radicals which then produce DNA strand breaks and crosslinks. If so, then one should be able to change the degree of cell kill by modifying sulfhydryl (SH) levels such that free radical processes are altered. Diamide, buthionine-S, R-sulfoximine, and N-ethylmaleimide (NEM) were used to reduce intracellular SH levels. Cysteamine and dithiotheitol were used to increase SH levels. In general, altered SH levels did not affect SAQ-induced cytotoxicity at low drug concentrations. When drug-tested cells were also irradiated, survival levels were generally those predicted from assuming purely additive interactions. On the other hand, survival after treatment with high concentrations of ADR and one other SAQ were decreased by concomitant treatment with NEM. Since altered SH levels do not produce changes in the potentiation of radiation-induced cell lethality by SAQs, it is concluded that free radicals are not involved in this potentiation. A free radical-mediated process may be involved in the cytotoxicity induced by ADR and other SAQs; however, it is not a simple process

The effect of vitamin E on cellular survival after X irradiation of lymphoma cells

International Nuclear Information System (INIS)

Fonck, K.; Kronings, A.W.T.

1978-01-01

Asynchronous cultures of a lymphocytic mouse leukaemic cell line L5178Y were X-irradiated under oxic and hypoxic conditions. The survival curves had almost no shoulder when the cells were grown under normal conditions and then irradiated in the presence of vitamin E, whereas a clear shoulder appeared when the cells were grown and irradiated in a medium supplemented with vitamin E (100 μg/ml). There was no change in the final sensitivity to lethal events in the vitamin E enriched cells. The results suggest that the radioprotective effect of vitamin E depends on its incorporation into the cell membranes. (U.K.)

Comparative evolution of coagulation disorders in baboons and Pigs after total body irradiation

International Nuclear Information System (INIS)

Destombe, C.; Lefleche, P.; Veyret, J.; Grasseau, A.; Agay, D.; Mestries, J.C.

1994-01-01

Acute total body irradiation in pigs, with a lethal dose of either gamma or mixed gamma-neutron radiation, induced similar plasmatic coagulation disorders as those observed in baboons. These data validated pathophysiological hypothesis which were developed during previous studies, but do not support the idea of a possible species specific radiosensitivity. (author)

Induction of dominant lethal mutations by alkylating agnets in germ-cells of the silkworm, Bombyx mori

International Nuclear Information System (INIS)

Murota, Tetsuo; Murakami, Akio.

1977-01-01

The comparison of the intensity of activity was made by measuring radiation equivalent chemical (REC) dose in the experiment of the induction of dominant lethal mutation, using the germ cells of pupae five days before the moths will be hatched. The alkylating agents employed in the experiment are methyl methanesulfonate (MMS), ethyl methanesulfonate (EMS), diethyl sulfate (DSC) and mitomycine-C (MC). X-ray irradiation was employed in order to indicate the capability of inducing mutation of the alkylating agents with the radiation equivalent chemical dose (REC dose). The dose-hatchability curves for the alkylating agents showed sigmoidal fashion as observed in X-ray, regardless of germ cells. The REC value at LD (50) was estimated by comparing the relative mutagenic capability of these chemicals. In sperm, EMS and DES with concentration of 1.0 x 10 -7 M/g showed the same lethality as about 2.3 kR and 0.6 kR of X-ray. However, no significant reduction of embryonic lethality after the treatment of pupae with MC (up to 2.1 x 10 -7 M/g) and MMS (up to 1.0 x 10 -6 M/g) was observed. As the results, the order of mutagenic effectiveness was as follows: EMS>DES>MMS approximately equal to MC. When oocytes in the mid-pupae were treated with MMS, EMS and MC with concentration of 1.0 x 10 -7 M/g, MMS and EMS showed the same effects as 12.8 kR and 0.6 kR. Surprisingly, MC showed the same lethality as 232.3 kR. This extremely high sensitivity of oocytes to MC may be ascribed to the inhibiting effect of the drug on the meiotic division. (Iwakiri, K.)

Pretreatment with ascorbic acid prevents lethal gastrointestinal syndrome in mice receiving a massive amount of radiation

International Nuclear Information System (INIS)

Yamamoto, Tetsuo; Kinoshita, Manabu; Shinomiya, Nariyoshi; Hiroi, Sadayuki; Sugasawa, Hidekazu; Majima, Takashi; Seki, Shuhji; Matsushita, Yoshitaro; Saitoh, Daizoh

2010-01-01

While bone marrow or stem cell transplantation can rescue bone marrow aplasia in patients accidentally exposed to a lethal radiation dose, radiation-induced irreversible gastrointestinal damage (GI syndrome) is fatal. We investigated the effects of ascorbic acid on radiation-induced GI syndrome in mice. Ascorbic acid (150 mg/kg/day) was orally administered to mice for 3 days, and then the mice underwent whole body irradiation (WBI). Bone marrow transplantation (BMT) 24 h after irradiation rescued mice receiving a WBI dose of less than 12 Gy. No mice receiving 14 Gy-WBI survived, because of radiation-induced GI syndrome, even if they received BMT. However, pretreatment with ascorbic acid significantly suppressed radiation-induced DNA damage in the crypt cells and prevented denudation of intestinal mucosa; therefore, ascorbic acid in combination with BMT rescued mice after 14 Gy-WBI. DNA microarray analysis demonstrated that irradiation up-regulated expressions of apoptosis-related genes in the small intestine, including those related to the caspase-9-mediated intrinsic pathway as well as the caspase-8-mediated extrinsic pathway, and down-regulated expressions of these genes in ascorbic acid-pretreated mice. Thus, pretreatment with ascorbic acid may effectively prevent radiation-induced GI syndrome. (author)

Lethal action of ultraviolet and visible (blue violet) radiations at defined wavelengths on human lymphoblastoid cells; action spectra and interaction sites

Energy Technology Data Exchange (ETDEWEB)

Tyrrell, R.M.; Werfelli, P.; Moraes, E.C. (Institut Suisse de Recherches Experimentales sur le Cancer, Lausanne)

1984-02-01

The repair proficient human lymphoblastoid line (TK6) has been employed to construct an action spectrum for the lethal action of ultraviolet (UV) radiation in the range 254 to 434 nm and to examine possible interactions between longer (334, 365 and 405 nm) and shorter wavelength (254 and 313 nm) radiations. The action spectrum follows a DNA absorption spectrum fairly closely out to 360 nm. As in previously determined lethal action spectra for procaryotic and eucaryotic cell populations, there is a broad shoulder in the 334 to 405 nm region which could reflect the existence of either (a) a non-DNA chromophore or (b) a unique photochemical reaction in the DNA over this region. Pre-treatment with radiation at 334 or 365 nm causes either a slight sensitivity to (low fluences) or protection from (higher fluences) subsequent exposure to radiation at a shorter wavelength (254 or 313 nm). Pre-irradiation at a visible wavelength (405 nm) at all fluence levels employed sensitizes the populations to treatment with 254 or 313 nm radiations. These interactions will influence the lethal outcome of cellular exposure to broad-band radiation sources.

Lethal action of ultraviolet and visible (blue violet) radiations at defined wavelengths on human lymphoblastoid cells; action spectra and interaction sites

International Nuclear Information System (INIS)

Tyrrell, R.M.; Werfelli, P.; Moraes, E.C.

1984-01-01

The repair proficient human lymphoblastoid line (TK6) has been employed to construct an action spectrum for the lethal action of ultraviolet (UV) radiation in the range 254 to 434 nm and to examine possible interactions between longer (334, 365 and 405 nm) and shorter wavelength (254 and 313 nm) radiations. The action spectrum follows a DNA absorption spectrum fairly closely out to 360 nm. As in previously determined lethal action spectra for procaryotic and eucaryotic cell populations, there is a broad shoulder in the 334 to 405 nm region which could reflect the existence of either (a) a non-DNA chromophore or (b) a unique photochemical reaction in the DNA over this region. Pre-treatment with radiation at 334 or 365 nm causes either a slight sensitivity to (low fluences) or protection from (higher fluences) subsequent exposure to radiation at a shorter wavelength (254 or 313 nm). Pre-irradiation at a visible wavelength (405 nm) at all fluence levels employed sensitizes the populations to treatment with 254 or 313 nm radiations. These interactions will influence the lethal outcome of cellular exposure to broad-band radiation sources. (author)

Hippophae leaf extract (SBL-1) countered radiation induced dysbiosis in jejunum of total body 60Cobalt gamma - irradiated mice

International Nuclear Information System (INIS)

Beniwal, C.S.; Madhu Bala

2014-01-01

Single dose of SBL-1 administered at the rate 30 mg/kg body weight (b.w.) 30 min prior to whole body 60 Co-gamma-irradiation at lethal dose (10 Gy), rendered >90% survival in comparison to zero survival in the non-SBL-1 treated 60 Co-gamma-irradiated (10 Gy) mice population (J Herbs Spices Med Plants, 2009; 15(2): 203-215). Present study investigated the effect of SBL-1 on jejunal microbiota in lethally irradiated mice. Study was performed with inbred Swiss albino Strain 'A' male mice (age 9 weeks) weighing 28±2 g. The animals were maintained under controlled environment at 26±2℃; 12 h light/dark cycle and offered standard animal food (Golden feed, Delhi) as well as tap water ad libitum. Metagenomic DNA was extracted, purified and quantified from jejunum of the mice. Universal primers (27f and 1492r) were used to amplify the 16S rRNA DNA from the metagenomic DNA. Amplicons were sequenced, vector contamination and chimeras were removed. The sequences (GenBank Accession No: KF681283 to KF681351) were taxonomically classified by using Sequence Match program, Ribosomal Database Project as well as by nucleotide-BLAST (E-value: 10, database: 16S rRNA gene sequences, Bacteria and Archea). Phylogenetic Tree was prepared using MEGA 5.2 package, using maximum likelihood algorithm after sequence alignment by MUSCLE. Thermus aquaticus was used as out-group to construct rooted tree. Branch stability was assessed by bootstrap analysis. Untreated animals and the animals treated with SBL-1 had 100% Lactobacillus; 60 Co gamma-irradiated animals had 55% Cohaesibacter (Alphaproteobacteria); 27% Mycoplasma (Tenericutes) and only 18% Lactobacillus; animals treated with SBL-1 prior to irradiation had 89% Lactobacillus and 11% Clostridium. This study demonstrated that treatment with SBL-1 at radioprotective doses before total body irradiation with lethal dose (10 Gy) countered the jejunal dysbiosis. (author)

Response of sublethally irradiated monkeys to a replicating viral antigen

International Nuclear Information System (INIS)

Hilmas, D.E.; Spertzel, R.O.

1975-01-01

Temporal effects of exposure to sublethal, total-body x radiation (400 R) on responses to vaccination with the attenuated Venezuelan equine encephalomyelitis vaccine virus, TC-83, were examined in rhesus monkeys. Viremia, often with delayed onset, was prolonged even when irradiation preceded vaccination by 28 days. Virus titers were increased, particularly in groups irradiated 4 or 7 days before vaccination. Delay in appearance of hemagglutination-inhibition and serum-neutralizing antibody correlated closely with persistence of viremia in irradiated-vaccinated monkeys. The temporal course of antibody response was markedly affected by the interval between irradiation and injection of this replicating antigen. With longer intervals between irradiation and vaccination, the somewhat depressed antibody responses approached normal or surpassed those of nonirradiated monkeys. Vaccination 14 days after radiation exposure resulted in lethality to 8 of 12 monkeys, apparently as a result of secondary infection. The additional lymphopenic stress due to the effect of TC-83, superimposed on the severely depressed hematopoietic competence at 14 days, undoubtedly contributed to this increased susceptibility to latent infection

Effects of X-irradiation on some aspects of protein metabolism in the frog, Rana hexadactyla

International Nuclear Information System (INIS)

Rajarami Reddy, G.; Sasira Babu, K.

1980-01-01

Changes in the level of total proteins and protease in brain, muscle and liver tissues of normal and X-irradiated frogs were determined. Low doses of radiation produced an increment in protein level while high doses produced decrement. However, protease activity at all doses exhibited an elevatory trend. Exposure of frogs to lethal doses resulted in increased protease activity and decreased protein content during post-irradiation periods. The results are discussed on the basis of protein destruction and lysosomal damage. (auth.)

Lentinan: hematopoietic, immunological, and efficacy studies in a syngeneic model of acute myeloid leukemia.

Science.gov (United States)

McCormack, Emmet; Skavland, Jørn; Mujic, Maja; Bruserud, Øystein; Gjertsen, Bjørn Tore

2010-01-01

Lentinan, a beta-glucan nutritional supplement isolated from the shitake mushroom (Lentula edodes), is a biological response modifier with immunostimulatory properties. Concomitantly, the role of beta-glucans as chemoimmunotherapeutic in a number of solid cancers has been widely documented. We investigated the effects of nutritional grade lentinan upon BN rats and in a preclinical syngeneic model of acute myeloid leukemia. BN rats supplemented daily with lentinan exhibited weight gains, increased white blood cells, monocytes, and circulating cytotoxic T-cells; and had a reduction in anti-inflammatory cytokines IL-4, IL-10, and additionally IL-6. Lentinan treatment of BN rats with BNML leukemia resulted in improved cage-side health and reduced cachexia in the terminal stage of this aggressive disease. Combination of lentinan with standards of care in acute myeloid leukemia, idarubicin, and cytarabine increased average survival compared with monotherapy and reduced cachexia. These results indicate that nutritional supplementation of cancer patients with lentinan should be further investigated.

Comparative studies on the effect of negative pions, 60Co gamma irradiation and hyperthermia on an in vitro 'tumour model'

International Nuclear Information System (INIS)

Luecke-Huhle, C.; Dertinger, H.; Schlag, H.; Weibezahn, K.F.

1977-01-01

Multicellular spheriods of Chinese hamster cells (V79) are much more resistant than monolayer cultures of the same cell line; this is observed after 60 Co γ-irradiation, after hyperthermic treatment, after combined treatment of heat with 60 Co γ-radiation and after exposure to negative pi-mesons. Intercellular communication within the three-dimensional cell clones seems to be responsible for an enhanced repair capacity for sub-lethal as well as for potentially lethal damage. While the response of spheroid cells to 60 Co γ-irradiation is almost independent of the state of growth, there is a clear difference in survival whether exponentially growing outer cells or inner plateau phase cells are exposed to heat: moderate heat treatment (4h at 42 0 C) leads to a greater killing efficiency of exponentially growing cells while the inner non-cycling cells exhibit a recruitment of resting cells into the proliferative compartment as demonstrated by means of flow-microfluorometry. Hyperthermia in combination with 60 Co γ-irradiation was shown to eliminate hypoxic cells and to yield a thermal enhancement ratio comparable to the RBE value obtained after pion irradiation at maximum LET. (author)

Scopolamine methylbromide mitigates radiation induced damage and lethality in zebrafish

International Nuclear Information System (INIS)

Shrivastava, Nitisha; Joshi, Jayadev; Ghosh, Subhajit; Dimri, Manali; Prem Kumar, Indracanti; Sehgal, Neeta

2014-01-01

In view of the strategic importance radiation countermeasures hold, the present study was undertaken to screen a collection of small molecule clinical compounds for possible radioprotective action using zebrafish as a model system. Preliminary screening in developing zebrafish embryos (24 hour post fertilization, (hpf)) using damage manifestations and survival as end point identified scopolamine methylbromide (SMB), a muscarinic receptor antagonist, as a potential radiomitigator. It was found to be optimal (60% survival advantage after 6 th post irradiation day) at a dose of 80 μM when added 3 h post 20 Gy exposure. Mechanistic studies suggested that SMB though exhibited no significant antioxidant potential, but was found to limit radiation induced apoptosis (pre G1 population) quantified through flow cytometry (6 and 5% reduction after 8 or 24 h after treatments) and annexin V staining (8% reduction). Further, quantitative analysis, using caspase 3 assay, revealed a 2.46 fold increase in apoptosis in irradiated group and treatment of irradiated zebrafish embryos with SMB led to a significant reduction in global apoptosis (1.7 fold; p<0.05) when compared to irradiated group. In silico studies based on structural and functional similarity with known radioprotectors suggested similarities with atropine, a known anti-inflammatory agent with muscarinic antagonism and radioprotective potential. In view of this SMB was tested, in silico, for possible anti-inflammatory action. Molecular docking studies revealed that SMB interacts (B.E-8.0 Kcal/mole) with cycloxygenase-2 (COX-2). In lieu of this, anti-inflammation activity was assessed through ChIN (chemically induced inflammation) method in 3 dpf (days post fertilization) embryos and SMB was found to significantly inhibit inflammation at all doses studied from 20-200 μM at 3 and 6 hpi (hours post inflammation). Overall the result suggests that scopolamine methylbromide mitigates radiation induced injury and lethality in

Selection and adaptation in irradiated plant and animal populations: a review

International Nuclear Information System (INIS)

Hart, D.R.

1981-03-01

Available literature on the effects of ionizing radiation on mutation rates, variability and adaptive responses to selection in exposed plant and animal populations is reviewed. Accumulated variability, and hence potential selection differentials, may be increased by many times due to induced mutation. The radiation dose that maximizes induced mutation varies greatly among species, strains and genetic systems. Induced variability tends to enhance the respose to selection, but this effect may be delayed or prevented by an initial reduction in the heritability of induced variation. Significantly, the detrimental effects of harmful mutations in irradiated populations may exceed the beneficial effects of selection for adaptive characteristics. Selection for radioresistance may occur at lethal or sub-lethal radiation doses but dose relationships are highly variable. (author)

Genetic effects of low-dose irradiation in Drosophila Melanogaster

International Nuclear Information System (INIS)

Zajnulin, V.G.; Shaposhnikov, M.V.; Yuraneva, I.N.

2000-01-01

Influence of chronic γ-irradiation at the dose rate of 0.17 cGy/h on the rate of genetic variability in the laboratory strains of Drosophila Melanogaster with genotypic distinguishes by families of mobile genetic elements and of systems of hybrid disgenesis and also violations in reparation processes control mechanisms. It was shown that the rates of induction of recessive lethal mutations depended on genotype of investigated strains. In the different strains an increase as well as a decrease of the mutation rate were observed. Also in was established that irradiation leads to the increase in frequencies of the gonads sterility and mutability of the sn w and h(w + ) in the P-M and H-E dysgenic crosses. Obtained results suggest that mobile genetic elements play an important role in the forming of genetic effects in response to low dose irradiation [ru

Regulation of antibody synthesis in the X-irradiated Mexican axolotl

International Nuclear Information System (INIS)

Charlemagne, J.

1981-01-01

The effects of X-irradiation were studied on the Mexican axolotl antibody synthesis. To reduce the anti-horse red blood cell (HRBC) antibody titers, 150 rd and smaller doses are ineffective, 200-450 rd are increasingly effective, and 700 rd are maximally effective (and lethal). A significant enhancement of the anti-HRBC titers was observed in low doses (50-150 rd X-irradiated animals). This enhancement was also observed when a low X-ray dose was applied only on the thymic areas. In whole body, but thymus area-shielded, 100 rd X-irradiated animals, the anti-HRBC titers were similar to those of the nonirradiated, HRBC-immunized control group. To explain these phenomena, it is suggested that a radiosensitive, adult thymectomy-sensitive and hydrocortisone-sensitive suppressor T cell subpopulation regulates the antibody synthesis in the axolotl. (orig.) [de

Regulation of antibody synthesis in the X-irradiated Mexican axolotl

Energy Technology Data Exchange (ETDEWEB)

Charlemagne, J.

1981-09-01

The effects of X-irradiation were studied on the Mexican axolotl antibody synthesis. To reduce the anti-horse red blood cell (HRBC) antibody titers, 150 rd and smaller doses are ineffective, 200-450 rd are increasingly effective, and 700 rd are maximally effective (and lethal). A significant enhancement of the anti-HRBC titers was observed in low doses (50-150 rd X-irradiated animals). This enhancement was also observed when a low X-ray dose was applied only on the thymic areas. In whole body, but thymus area-shielded, 100 rd X-irradiated animals, the anti-HRBC titers were similar to those of the nonirradiated, HRBC-immunized control group. To explain these phenomena, it is suggested that a radiosensitive, adult thymectomy-sensitive and hydrocortisone-sensitive suppressor T cell subpopulation regulates the antibody synthesis in the axolotl.

Lethality of Rendang packaged in multilayer retortable pouch with sterilization process

Science.gov (United States)

Praharasti, A. S.; Kusumaningrum, A.; Frediansyah, A.; Nurhikmat, A.; Khasanah, Y.; Suprapedi

2017-01-01

Retort Pouch had become a choice to preserve foods nowadays, besides the used of the can. Both had their own advantages, and Retort Pouch became more popular for the reason of cheaper and easier to recycle. General Method usually used to estimate the lethality of commercial heat sterilization process. Lethality value wa s used for evaluating the efficacy of the thermal process. This study aimed to find whether different layers of pouch materials affect the lethality value and to find differences lethality in two types of multilayer retort pouch, PET/Aluminum Foil/Nylon/RCPP and PET/Nylon/Modified Aluminum/CPP. The result showed that the different layer arrangement was resulted different Sterilization Value (SV). PET/Nylon/Modified Aluminum/CPP had better heat penetration, implied by the higher value of lethality. PET/Nylon/Modified Aluminum/CPP had the lethality value of 6,24 minutes, whereas the lethality value of PET/Aluminum Foil/Nylon/RCPP was 3,54 minutes.

Induction of immune resistance against L1210 lymphatic leukemia in mice after chemoradiotherapy of the leukemia and reconstitution with bone marrow purged from the leukemia with mafosfamide

International Nuclear Information System (INIS)

Skorski, T.; Kawalec, M.

1988-01-01

Lymphatic leukemia L1210-bearing semisyngeneic Balb/c x DBA/2Wf F1 (CD2F1) mice were subjected to chemoradiotherapy (2 x 100 mg/kg of cyclophosphamide i.p. and 1000 cGy of total body irradiation) and reconstitution with 10(7) syngeneic bone marrow cells i.v. The bone marrow obtained from leukemic mice was previously ex vivo purged of the leukemia cells with mafosfamide (ASTA Z7654) and stored in liquid nitrogen. Eight weeks after cytoreductive therapy and bone marrow transplantation we tried to immunize the mice against the lethal dose of the leukemia by i.p. injections of L1210-Maf cells (L1210 cells treated in vitro with mafosfamide for inhibition of their growth). About 75% of such mice were able to reject the subsequent 10(3) L1210 leukemia cell challenge, as compared with 70% of normal immunized mice and 55% of mice reconstituted with bone marrow cells not treated with mafosfamide

Control of potato tuberworm, Phthorimaea operculella (Zeller) (Lepidopetra : Gelechiidae) : effect of gamma-irradiation on developmental stages

Energy Technology Data Exchange (ETDEWEB)

Rananavare, H D; Harwalkar, M R; Rahalkar, G W [Bhabha Atomic Research Centre, Bombay (India). Pest Control Section

1989-06-01

Eggs of potato tuberworm (0 to 64hr) were irradiated with doses ranging from 1 to 5 Krad. For a given dose, the radiosensitivity of eggs decreased with increase in age and the decrease was larger with dose of 3 Krad and above. When pupae of different ages were irradiated with dose of 20, 25 and 30 Krad, adult emergence increased with age at irradiation and decreased at higher doses. Irradiation of eggs and pupae to obtain competitive sterile adult male was not feasible. Adult irradiation was found most ideal and near complete sterility (96.3 per cent) was induced when freshly emerged males were irradiated with a dose of 45 Krad. Induced sterility was the result of induction of dominant lethal mutation in the sperm and was permanent. (author). 4 tabs., 14 refs., 4 figs.

[Bladder tumor lethality. Results in the autonomous community of Rioja between 1975-1991].

Science.gov (United States)

Fernández Fernández, A; Gil Fabra, J; Fernández Ruíz, M; Angulo Castellanos, M G; Blanco Martín, E; Otero Mauricio, G

1998-01-01

Between 1975-1991, a total of 557 cases of bladder carcinoma were identified in the Autonomous Community of La Rioja (CAR) which were followed up to December 1994. The overall lethality was 21.9%. 492 cases with 22.35% lethality were identified in males. In females, however, there was 65 cases with 18.46% lethality. The comparison of males and females lethality resulted in p = 0.525. Lethality between cases diagnosed within each 5-year period analyzed is: 1975-1981: 177 cases, lethality 23.72%. 1982-1986: 168 cases, lethality 30.95%. 1987-1991: 212 cases, lethality 13.20%. Between the first and the second 5-year periods, p = 0.132; between the first and third 5-year periods p = 0.007 and between the second and third 5-year periods p CAR for a 22.35% lethality. Lethality is higher in males that in females but the difference is not statistically significant. In the last 5-year period assessed, 1987-1991, a reduction of lethality from bladder neoplasms has been documented.

Photoreactivity in Saccharomyces cerevisiae cells after irradiation with 25 MeV electrons

International Nuclear Information System (INIS)

Tsyb, T.S.; Seleva, N.G.; Myasnik, M.N.; Kabakova, N.M.

1986-01-01

Significant photoreactivation was noted in radio- and UV-sensitive rad-mutants of Saccharomyces cerevisiae cells exposed to 25 MeV electrons. In order to make the photoreactivable damage be manifest anoxic conditions of irradiation should be chosen as optimal ones. It was shown that the low oxygen effect was partially associated with the photoreactivable damage involved in the lethal effect of ionizing radiation

Immunization of mice with gamma-irradiated intramuscularly injected schistosomula of Schistosoma mansoni

International Nuclear Information System (INIS)

Bickle, Q.D.; Taylor, M.G.; Doenhoff, M.J.; Nelson, G.S.

1979-01-01

The parameters involved in the induction of resistance against Schistosoma mansoni by injection of irradiated, artificially transformed schistosomula were studied in mice. Single intramuscular injections of 500 schistosomula exposed to radiation doses in the range 2.3 to 160 krad. resulted in significant protection ( in the range 20 to 50% as assessed by reduced worm burdens) against a challenge infection administered at intervals from 3 to 24 weeks post-vaccination. However, schistosomular irradiated with 20 krad. consistently resulted in better protection than those exposed to either higher or lower radiation doses despite the persistence of stunted adults from the infections irradiated with 2.3 krad. Vaccination with 40 krad. schistosomula resulted in significant protection in terms of reduced worm and tissue egg burdens and increased survival following lethal challenge. Varying the number of irradiated schistosomula, the frequency and route of their administration, the site of challenge and the strain of host all failed to enhance the level of resistance. However, percutaneously applied, irradiated cercariae were found to be more effective in stimulating resistance (60%) than intramuscularly injected, irradiated schistosomula (40%). (author)

Alternative strawberry disease management strategy: combing low UV-C irradiation in dark, disabling pathogen’s UV-C repair mechanism, and preventing pathogen establishment with biocontrol agents

Science.gov (United States)

The limitations of current fungicides necessitate a search for new approaches. Low-dose or sub-lethal UV-C irradiation (12.36 J/m2) alone is not effective in controlling fungal diseases, especially when the plants are exposed to UV-C irradiation during the day. We found, however, that application ...

Radiation and chemically induced potentially lethal lesions in noncycling mammalian cells: recovery analysis in terms of x-ray- and ultraviolet-like-systems

International Nuclear Information System (INIS)

Hahn, G.M.

1975-01-01

Recovery from and fixation of potentially lethal damage after exposure of Chinese hamster cells to uv and to x irradiation were investigated, as was recovery after exposure to chemotherapeutic agents. Recovery after uv radiation has a T/sub 1 / 2 / of about 20 hr; the fraction of cells able to undergo recovery depends upon nutritional factors both before and after exposure. After x irradiation, recovery proceeds with a T/sub 1 / 2 / of approximately 2 hr and is much less influenced by nutritional factors. Fixation after serum stimulation has a T/sub 1 / 2 / of 3 to 4 hr in uv-irradiated cells, a T/sub 1 / 2 / of 30 min in x-irradiated cells. Recovery kinetics after nitrogen mustard and bleomycin exposures mimic those for x-ray exposure; after methyl methane sulfonate the kinetics are mainly uv-like, though with an x-ray-like component. Recovery by cells with BUdR-substituted DNA and irradiated with visible light is primarily x-ray-like, though with a uv-like component. There is no recovery by cells exposed to adriamycin or to 1,3-bis(2-chloroethyl)-1-nitrosourea

Effects of whole-body x irradiation on the biogenesis of creatine in the rat

International Nuclear Information System (INIS)

Thyagarajan, P.; Vakil, U.K.; Sreenivasan, A.

1977-01-01

Influences of whole-body x irradiation on various aspects of creatine metabolism have been studied. Exposures to sublethal or lethal doses of x radiation results in excessive urinary excretion as well as higher accumulation of creatine in the skeletal muscle of x-irradiated rats. A sudden fall in CPK activity in muscle with a concomitant rise in serum suggests that changes in serum and tissue CPK activity are of an adaptive nature in rats exposed to sublethal doses of x radiation. In vitro studies on creatine synthesis shows that transaminidase and methyl transferase activities in kidneys and liver, respectively, are decreased on the 5th day in the x-irradiated, are decreased on the 5th day in the x-irradiated rat. However, on the 8th day, the enzyme activities are restored to normal

A study of the physiological changes and the nutritional qualities of irradiated apples and the effect of irradiation on apples stored at room temperature

International Nuclear Information System (INIS)

Wang Chuanyao; Jiang Mengyue; Gao Meixu; Ma Xiuye; Zhang Shufen; Liu Shucheng

1993-01-01

The effects of γ-irradiation on the metabolism and nutritional qualities of Golden Delicious apples and on the lethality of pathogenic fungi have been studied. The storage effect of irradiation on apples at room temperature has been observed. Results showed that the respiratory intensity of irradiated apple at 0.3-0.5 kGy was near or lower than that of unirradiated apple after 15 days irradiation. The amount of ethylene release was obviously inhibited when fruits were irradiated with 0.3-0.7 kGy. The flesh firmness of apples irradiated with 0.3-0.9 kGy was higher than that of unirradiated apple with increased storage time. The negative correlations between the flesh firmness and the activities of pectinesterase (PE), polygalacturonase (PG) were observed when the dosage was lower than 1.5 kGy. The 2.0 kGy irradiation damaged the ultrastructure of cells, induced the softening of apple. When apples were irradiated with 0.7-2.0 kGy, the contents of 4 important volatile components of apple would be decreased. However, this dose had no effects on the pure chemicals. Studies showed that there was no significant effect of irradiation with 0.3-2.0 kGy on the nutritional qualities of apples and this dose range could effectively control the verticillate pathogenic fungi. The result of storage experiment showed that rotting of fruits decreased by 0.3-0.9 kGy irradiation. (author)

Lethal Effect on Bacterium of Decay of Incorporated Radioactive Atoms (3H, 14C, 32P)

International Nuclear Information System (INIS)

Apelgot, Sonia

1968-01-01

The biological effect of decay of 3 H, 14 C and 32 P incorporated into a bacterium depends on the nature of the organic molecule labelled, on the position of the isotope within it and on the isotope itself. In sum, results obtained to date show that: The decay of 3 H atoms incorporated into certain macromolecules of a bacterium causes sterilization through ionization by the ß - particle emitted; transmutation is of negligible importance. This self-irradiation is comparable in effect with X-rays and is affected in a similar manner by the same factors: temperature, presence of a radioprotector, radiosensitivity of the strain. Decay of 14 C or 32 P atoms incorporated into bacterial DNA is lethal because of the transmutation effect; ionizations produced by emitted ß - particles may be disregarded. Survival curves for 32 P transmutations depend on the experimental conditions. Some of the results obtained with 32 P are similar to those obtained with X-rays, e.g. effects of temperature, radical capture and oxygen, while others are similar to those of u.v. light, e.g., effect of growth conditions. Comparative tests made with 32 P indicate that the recoil energy of transmutation is not the phenomenon responsible for the lethal effect observed. Comparison of the results obtained after X-irradiation or decay of 3 H or 32 P incorporated into the DNA of bacteria of the same strain of E. coli shows that the efficiency of a 32 P transmutation is about four times greater than that of an ionization produced at random within the same DNA. (author) [fr

Humanitarian Algorithms : A Codified Key Safety Switch Protocol for Lethal Autonomy

OpenAIRE

Nyagudi, Nyagudi Musandu

2014-01-01

With the deployment of lethal autonomous weapons, there is the requirement that any such platform complies with the precepts of International Humanitarian Law. Humanitarian Algorithms[9: p. 9] ensure that lethal autonomous weapon systems perform military/security operations, within the confines of International Humanitarian Law. Unlike other existing techniques of regulating lethal autonomy this scheme advocates for an approach that enables Machine Learning. Lethal autonomous weapons must be ...

Anti-lipopolysaccharide toxin therapy for whole body X-irradiation overdose

Energy Technology Data Exchange (ETDEWEB)

Gaffin, S.L.; Wells, M.; Jordan, J.P.

1985-09-01

Death in humans from ionising radiation overexposure in the 3-8 Gy (300-800 rad) range is in part due to the toxaemia caused by the entry of gram-negative bacteria and/or their lipopolysaccharide toxin (LPS) into the blood circulation through the walls of partially denuded gut. Anti-LPS hyperimmune equine plasma was evaluated for its ability to lower irradiation-induced lethality. Mice were irradiated with 6.3 Gy (630 rad) and six days later received equine Anti-LPS hyperimmune plasma, control plasma or saline. Mortalities in the three groups were 58%, 92% and 79% (p < 0.01) respectively. Thus Anti-LPS may prove useful as an adjunct to conventional therapy in treating radiation sickness.

Anti-lipopolysaccharide toxin therapy for whole body X-irradiation overdose

International Nuclear Information System (INIS)

Gaffin, S.L.; Wells, M.; Jordan, J.P.

1985-01-01

Death in humans from ionising radiation overexposure in the 3-8 Gy (300-800 rad) range is in part due to the toxaemia caused by the entry of gram-negative bacteria and/or their lipopolysaccharide toxin (LPS) into the blood circulation through the walls of partially denuded gut. Anti-LPS hyperimmune equine plasma was evaluated for its ability to lower irradiation-induced lethality. Mice were irradiated with 6.3 Gy (630 rad) and six days later received equine Anti-LPS hyperimmune plasma, control plasma or saline. Mortalities in the three groups were 58%, 92% and 79% (p<0.01) respectively. Thus Anti-LPS may prove useful as an adjunct to conventional therapy in treating radiation sickness. (author)

Mechanistic and kinetic aspects of microbial inactivation in food irradiation processes

International Nuclear Information System (INIS)

Tukenmez, I.

2004-01-01

Full text: A proper reaction mechanism was searched by analyzing the inactivation processes of microorganisms during food irradiation by ionizing radiation. By employing transition-state theory, it was assumed that the overall inactivation process involves a reversible sub-lethal stress and repair reactions to form reversibly injured cell or sensitized cell, which then undergoes irreversible injury leading to dead cell. A shoulder in low dose range in survival kinetics was associated with the repair process. Depending on the postulated mechanism, kinetic model equations were derived. The kinetics of cell inactivation by irradiation was expressed as depending on irradiation dose. By using experimental data in the developed model the inactivation parameters including threshold dose, radiation yield, decimal reduction dose and minimum sterilization dose were evaluated and microbial inactivation by irradiation was simulated by using the numerical values of the parameters. Developed model and model parameters may be used for the process control and the assessment of product quality in radiation preservation of food

Induction of mutation and recombination following UV irradiation during meiosis in Saccharomyces cerevisiae

Energy Technology Data Exchange (ETDEWEB)

Kelly, S.L.; Parry, J.M. (University Coll. of Swansea (UK). Dept. of Genetics)

1983-03-01

Irradiation of yeast cultures with ultraviolet light at discrete stages during meiosis produces cyclic variations in sensitivity, i.e. cells are more sensitive to the lethal effects of UV light prior to entry into the meiotic DNA synthesis, and this corresponds to a peak of induction of point mutation. Cells become more resistant to both induced point mutation and lethality as they enter meiotic DNA synthesis, but become more sensitive again during spore formation. The induced level of intragenic recombination rises during the period of commitment ot recombination to a level indistinguishable from the full meiotic level of spontaneous intragenic recombination. Induced reciprocal recombination remains above the spontaneous level up to the point of commitment to sporulation.

Non-Lethal Weapons Program

Science.gov (United States)

Sheets Frequently Asked Questions Non-Lethal Weapons FAQs Active Denial System FAQs Human Electro -Muscular Incapacitation FAQs Related Links Business Opportunities Contact JNLWD Congressional Engagement , Wednesday, Sept 20, 2017. The Active Denial System, blunt-impact munitions, dazzling lasers, LRAD 100X

Opposite effects of total lymphoid irradiation on T cell-dependent and T cell-independent antibody responses

Energy Technology Data Exchange (ETDEWEB)

Tanay, A.; Strober, S.

1984-02-01

The effect of total lymphoid irradiation (TLI) on the primary antibody response to the dinitrophenylated heterologous protein, keyhole limpet hemocyanin (DNP-KLH), in complete Freund's adjuvant (CFA), and to the trinitrophenylated polysaccharide antigen, Brucella abortus (TNP-BA), was studied in BALB/c mice. The antibody response to both antigens was diminished in comparison with nonirradiated mice when antigens were injected within 3 days after TLI. When the mice were immunized 30 days after completion of TLI the antibody response to DNP-KLH in CFA was still diminished, but the antibody response to TNP-BA was enhanced 5- to 10-fold as compared with that of control animals. The opposite effect of TLI on the two antibody responses was also observed in a syngeneic primary adoptive transfer system.

Appearance of thymic nurse cells after gamma irradiation

International Nuclear Information System (INIS)

Mulder, A.H.; Bekkum, D.W. van

1983-01-01

Since prothymocytes home from the bone marrow to the thymus, it was tested in the mouse whether prothymocytes could be recaptured from thymic nurse cells (TNC). Bone marrow cells were labelled with the red fluorescing anthracycline daunomycin and varying numbers (up to 25 x 10 6 nucleated bone marrow cells) were injected into lethally irradiated recipients. At several time intervals after transplantation (up to 24 hours), thymuses were removed and the TNCs were isolated. No specific red fluorescence was found within the TNCs. These experiments were repeated with supravital compounds at concentrations which have been shown not to affect viability, homing pattern and function. Again, no specific fluoresence was found in the TNC after transplantation of labelled bone marrow into irradiated mice. The relationship between the dose of total body gamma irradiation and the time after irradiation was investigated. Maximal numbers of TNCs were found at 6 hours after irradiation with 4 Gy. Eight to 12 hours after irradiation, the number of TNCs isolated decreased and had returned to preirradiation levels at 24 hours. The relation between TBI dose and the number of TNCs per thymus is shown. The number determined at 3 hours increased with the dose to reach a maximum at 4 Gy. The authors later studied the morphology of the TNCs isolated at 4 to 6 hours after irradiation. On electron microscopic examination, signs of degeneration and death of the enclosed thymocytes was detected. (Auth.)

γ-irradiation-induced mortality: protective effect of protease inhibitors in chickens and mice

International Nuclear Information System (INIS)

Palladino, M.A.; Galton, J.E.; Troll, W.; Thorbecke, G.J.

1982-01-01

Chickens (Gallus domesticus) were protected from the acute γ-irradiation-induced mortality (within 24 hours) by the proteolytic enzyme inhibitors, soy-bean trypsin inhibitor (SBTI), lima bean inhibitor (LBTI), antipain, α-N-benzoyl-L-arginine ethyl ester HCl (BAEE), trasylol, and leupeptin. Several other enzyme inhibitors, p-tosyl-L-arginine methyl ester HCl (TAME), α-tosyl-lysyl-chloromethyl ketone HCl (TLCK) and epsilon-amino caproic acid (EACA), did not protect. EACA even increased the mortality caused by γ-irradiation. The pattern of protective enzyme inhibitors suggests involvement of a kallikrein-like enzyme. SBTI and antipain also protected against low range lethal γ-irradiation exposures, 690 R in BALB/c and 880 R in SJL/J mice. It is suggested that enhanced vascular permeability, which in chickens is known to be the cause of the irradiation mortality during the first 24 hours, may also contribute to the mortality in mice during the first week after irradiation. (author)

Increased haematopoietic stem cell survival in mice injected with tocopherol after X-irradiation

International Nuclear Information System (INIS)

Roy, R.M.; Malick, M.A.; Clark, G.M.

1982-01-01

Tocopherol injection (2.5 mg) immediately after irradiation reduced lethality only during bone-marrow syndrome. Endogenous spleen colony count at 8 days after X-radiation were significantly greater in vitamin-E-injected mice compared to noninjected or vehicle-injected animals; however, 59 Fe incorporation into spleen and bone marrow did not suggest enhanced erythropoietic activity in vitamin-E-injected groups at 2, 4, 8 and 10 days following irradiation. Mitotic index and frequency of micronuclei in marrow at 24 hours post irradiation (3 GY) were unaffected by tocopherol injection. The uptake of tritium from injected 3 H-tocopherol suggests that tocopherol has been accumulated in spleens but not marrows of irradiated animals within a few hours. Also tocopherol has no effect on endogenous spleen colony counts if injected after 5 hours nor is there an effect on the seeding efficiency of exogenous bonemarrow cells injected into recipients receiving tocopherol after irradiation. (orig.) [de

Enhanced reactivation and mutagenesis of UV-irradiated adenovirus in normal human fibroblasts

International Nuclear Information System (INIS)

Bennett, C.B.; Rainbow, A.J.

1988-01-01

UV-enhanced reactivation (UVER) and UV-enhanced mutagenesis (UVEM) for two adenovirus temperature-sensitive mutants were examined following the infection of normal human fibroblasts. UV-irradiation of the virus alone resulted in dose-dependent increase in the UV-induced reversion frequency (RF) of viral progeny and a dose-dependent exponential decrease in progeny survival, when infecting non-irradiated cells. Analysis of the slopes of the UV-induced reversion curves suggested that 2.5 ± 0.3 and 2.4 ± 0.5 'hits' were required to produce a targeted reversion event among the viral progeny of Ad5ts36 and Ad5ts125 respectively. UV-irradiation of cells 24 h prior to infection resulted in a significant increase in progeny survival for UV-irradiated virus (UVER factor = 3.4 ± 0.8) concomitant with a significant increase in RF for UV-irradiated virus (targeted increase = 1.9 ± 0.3). The UV-induced RF per lethal hit to the virus was also significantly greater in UV-irradiated compared with non-irradiated cells. These results are consistent with the existence of a UV-inducible error-prone DNA repair mechanism in normal human cells. (author)

Non-Lethal Weapons: Opportunities for R&D

Science.gov (United States)

2004-12-01

during the Vietnam War. US; emulsifying agents are used in food processing, drilling fluids, cosmetics , pharmaceuticals, heavy- duty cleaners, textile...conducted in a professional manner, with no threat to public safety or the environment. 11 References [1] Fenton , G., (2001). NLW Technology Taxonomy...W.A., Mason, R.L., Collins, K.R., (2000). Non-Lethal Applicants of Slippery Substances. NDIA Non-Lethal Defense IV. [24] Fenton , G., (2000). Overview

Photomimetic effect of serotonin on yeast cells irradiated by far-UV radiation

International Nuclear Information System (INIS)

Fraikin, G.Y.; Strakhovskaya, M.G.; Rubin, L.B.

1982-01-01

The effect of serotonin on the survival of far-UV irradiated cells of the yeast Candida guilliermondii was studied. Serotonin was found to have a photomimetic property. Preincubation of cells with serotonin results in protection against far-UV inactivation, whereas the post-radiation treatment with serotonin causes a potentiation of far-UV lethality. Both effects are similar to those produced by near-UV (334 nm) radiation. The observations provide support to the previously proposed idea that photosynthesized serotonin is the underlying cause of the two effects of near-UV radiation, photoprotection and potentiation of far-UV lethality. Experiments with an excision-deficient strain of the yeast Saccharomyces cerevisiae suggest that the effect of serotonin is by its binding to DNA. (author)

Molecular basis for the mutagenic and lethal effects of ultraviolet irradiation. Progress report

International Nuclear Information System (INIS)

1977-01-01

Pathways of DNA repair in bacteria and mammalian cells. Progress is reported on the following studies: genetic control of incision and excision in Escherichia coli; effects of binding proteins on the repair process in vitro; location of endonuclease - uv-irradiated DNA complexes; identification of eukaryotic repair mechanisms; nuclear complementation in HeLa cells; enzyme isolation from repair syndrome skin fibroblasts; and expression of the E. coli - SV40 hybrid DNA

Lethal synergy involving bicyclomycin: an approach for reviving old antibiotics.

Science.gov (United States)

Malik, Muhammad; Li, Liping; Zhao, Xilin; Kerns, Robert J; Berger, James M; Drlica, Karl

2014-12-01

One way to address the growing problem of antimicrobial resistance is to revive old compounds that may have intrinsic lethal activity that is obscured by protective factors. Bicyclomycin is an old inhibitor of the Rho transcription terminator that by itself shows little rapid lethal activity. However, bicyclomycin participates in bacteriostatic synergy, which raises the possibility that conditions for lethal synergy may exist, perhaps through a suppression of protective factors. Bicyclomycin was combined with bacteriostatic inhibitors of gene expression, and bactericidal activity was measured with several cultured Gram-negative pathogens. When used alone, bicyclomycin failed to rapidly kill growing cultures of Escherichia coli; however, the additional presence of bacteriostatic concentrations of tetracycline, chloramphenicol or rifampicin led to rapid killing. Four other pathogen species, Acinetobacter baumannii, Klebsiella pneumoniae, Salmonella enterica serotype Typhimurium and Shigella dysenteriae, also exhibited enhanced killing when bicyclomycin was combined with tetracycline or rifampicin. This lethal synergy was achieved at low concentrations (slightly above the MIC) for all agents tested in combinations. Follow-up work with E. coli indicated that lethal synergy arose from a blockage of transcription elongation. Moreover, lethal synergy was reduced when bicyclomycin was added 60 min before tetracycline, suggesting that bicyclomycin induces a protective factor. The action of bicyclomycin illustrates the potential present in a largely abandoned antibacterial agent; it exhibits lethal synergy when coadministered with known, bacteriostatic inhibitors of gene expression. The identification of protective factors, which are currently uncharacterized, may reveal new ways to promote the lethal action of some old antibiotics. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved

Sex differences in the MB49 syngeneic, murine model of bladder cancer.

Science.gov (United States)

White-Gilbertson, Shai; Davis, Megan; Voelkel-Johnson, Christina; Kasman, Laura M

The MB49 syngeneic, murine model of bladder cancer has been widely used for more than 35 years. In humans, bladder cancer is one third as prevalent in women as in men, with a trend toward lower prevalence in parous compared to nulliparous women. Our objective was to determine if the MB49 bladder cancer model reproduces the sex differences observed in humans, and to determine its sensitivity to testosterone and the pregnancy hormone, human chorionic gonadotropin (hCG). Male and female C57BL/6 mice were implanted with MB49 murine bladder cancer cells, and observed for tumor growth. MB49 dose responses to hCG and dihydrotestosterone were determined in vitro . MB49 tumor growth was significantly greater in male mice than female mice. Pregnancy did not affect MB49 tumor growth in female mice. MB49 cells did not proliferate in response to hCG in vitro and the functional receptor for gonadotropins was absent. Dihydrotestosterone strongly stimulated growth of MB49 cells in vitro . The MB49 murine model of bladder cancer reproduced some aspects of the sex differences observed in humans. Our results suggest that testosterone may stimulate MB49 cell proliferation, which may explain the more rapid MB49 tumor growth observed in male mice.

Two types of T helper cells in mice: Differences in cellular immune functions and cytokine secretion - selective reduction of one type after total lymphoid irradiation

International Nuclear Information System (INIS)

Bass, H.Z.

1989-01-01

As observed from a large panel of mouse T helper clones, there are at least two subsets of CD4 + T cells that both differ in function and demonstrate distinct patterns of cytokine secretion after antigen or mitogen stimulation. Th1 cells synthesize IL-2, INF-γ and lymphotoxin. They produce a DTH reaction in the footpads of naive mice. In addition, Th1 cells are required for the generation of CTL, and they appear to augment IgG2a antibody production. In contrast, by secreting IL-4, IL-5, and IL-6, Th2 cells play an essential role in humoral immunity. TLI consists of high dose, fractionated irradiation delivered selectively to the major lymphoid tissues. Four to six weeks after TLI, the CD4 + cells of the treated mice (counted as a percentage of the total spleen lymphocytes) recover to the similar levels as those in normal BALB/c mice. These CD4 + cells can help normal syngeneic B cells to produce a vigorous antibody response to TNP-KLH in adoptive cell transfer experiments, but the same cells are inactive in the MLR, and they fail to transfer DTH in TNP-KLH primed syngeneic BALB/c mice

Study of the radio restoration effects of some biochemical compounds on mice embryos (Oryza sativa L. var. Cigalon) irradiated with cobalt 60 gamma radiations

International Nuclear Information System (INIS)

Al Harithi, S.

1982-01-01

Research work on improvement of mutagenesis experiment techniques with emphasis on an improved repair of potentially lethal damage induced by high gamma radiation doses in rice embryos. The protective and recovery effects of the following biochemicals were investigated: cytokinines; indolylacetic acid; glucose; glucose phosphate; ATP; ATP-MG ++ complex; spermidine; cyclic AMP and cyclic GMP. Only ATP-MG ++ , C-AMP and C-GMP were able to increase the survival fraction of lethally irradiated rice embryos [fr

Radioprotective effects of chlorogenic acid against mortality induced by gamma irradiation in mice

International Nuclear Information System (INIS)

Seyed Jalal Hosseinimehr; Amirhossein Ahmadi; Shahram Akhlaghpoor; Tehran University of Medical Sciences, Tehran

2007-01-01

Complete text of publication follows. The radioprotective effects of the naturally occurring compound chlorogenic acid has been investigated against mortality induced by gamma irradiation in mice. Chlorogenic acid administrated at single doses of 100, 200 and 400 mg/kg 1 and 24 h prior to lethal dose of gamma irradiation (8.5 Gy). At 30 days after treatment, the percentage of animal survival in each group was: control, 20%; 100 mg/kg, 20% and 15%; 200 mg/kg, 45% and 15%; 400 mg/kg, 25% and 35% for 1 h and 24 h treatment prior gamma irradiation, respectively. Percentage of survival increased in animal treated with this agent at 200 mg/kg at 1 h statistically compared with irradiated alone group. Other doses of chlorogenic acid have not showed any enhanced survival at 1 and 24 h before irradiation. Chlorogenic acid exhibited concentration-dependent activity on 1, 1-diphenyl 2-picrylhydrazyl free radical to show strong antioxidant activity. It appeared that chlorogenic acid with antioxidant activity reduced mortality induced by gamma irradiation.

Cultured cells from a severe combined immunodeficient mouse have a slower than normal rate of repair of potentially lethal damage sensitive to hypertonic treatment

International Nuclear Information System (INIS)

Kimura, H.; Terado, T.; Ikebuchi, M.; Aoyama, T.; Komatsu, K.; Nozawa, A.

1995-01-01

The effects of hypertonic 0.5 M NaCl treatment after irradiation on the repair of DNA damage were examined in fibroblasts of the severe combined immunodeficient (scid) mouse. These cells are hypersensitive to ionizing radiation because of a deficiency in the repair of double-strand breaks. Hypertonic treatment caused radiosensitization due to a fixation of potentially lethal damage (PLD) in scid cells, demonstrating that scid cells normally repair PLD. To assess the kinetics of the repair of PLD, hypertonic treatment was delayed for various times after irradiation. Potentially lethal damage was repaired during these times in isotonic medium at 37 degrees C. It was found that the rate of repair of PLD was much slower in scid cells than in BALB/c 3T3 cells, which have a open-quotes wild-typeclose quotes level of radiosensitivity. This fact indicates that the scid mutation affects the type of repair of PLD that is sensitive to 0.5 M NaCl treatment. In scid hybrid cells containing fragments of human chromosome 8, which complements the radiosensitivity of the scid cells, the rate of repair was restored to a normal level. An enzyme encoded by a gene on chromosome 8 may also be connected with PLD which is sensitive to hypertonic treatment. 29 refs., 3 figs

Splenocytes cultured in low concentrations of IL-2 generate NK cell specificities toward syngenic and allogenic targets

DEFF Research Database (Denmark)

Nissen, Mogens Holst; Jeppesen, M; Claesson, M H

2000-01-01

Splenocytes cultured in the presence of 30-60 units/ml IL-2 for 5 days develop natural killer activity toward syngeneic and allogeneic tumor cell targets. The IL-2 activated splenocytes, themselves, are partially resistant, whereas concanavalin A-activated T blast cells are completely resistant...... to killing. Surprisingly, major histocompatibility complex (MHC)-I-negative target cells are also resistant to natural killer (NK)-cell-mediated killing. Cells resistant to killing were unable to block NK-cell-mediated killing of sensitive targets as judged from cold target cell inhibition experiments......, and one type of target cells sensitive to killing did generally not cross-block killing of other killing-sensitive target cell types. Alloantigen exposure of splenocytes, i.e., one-way mixed lymphocyte cultures, partially prevents the development of NK-cell activity. Our data suggest that target...

[Autoantibody formation against the antigens of the synaptonemal complex in the syngeneic immunization of male Mus musculus].

Science.gov (United States)

Dadashev, S Ia; Gorach, G G; Kolomiets, O L

1994-01-01

Male mice were immunized with the suspension of synaptonemal complexes (SC) isolated from mouse spermatocytes nuclei. The indirect immunofluorescent analysis showed the active binding of sera obtained from immunized mice to SC of mouse spermatocyte spreads. At early and mid-pachytene, SC can be clearly identified in 19 autosome bivalents and in sex chromosome bivalent. According to the electron microscopic analysis, all structural elements of SC bind antibodies. Metaphase chromosomes were not stained with the immune sera. Specificity of interaction between SC components and antibodies was confirmed in a series of control experiments. Analysis of sera obtained from mice after their syngeneic immunization with isolated SC fraction suggested that certain mouse SC components induce the formation of autoantibodies. This, in turn, suggests that these SC components are meiosis-specific.

The effect of recovery from potentially lethal damage on the determination of repair and repopulation in a murine tumour

International Nuclear Information System (INIS)

Sheldon, P.W.; Fowler, J.F.

1985-01-01

Repair and repopulation following X irradiation of clamped-off murine anaplastic MT tumours was investigated using the established method of (Dsub(n)-D 1 )/(n-1). Repair was complete in 4 h, similar in extent to that reported in other tumours, and within the range of that reported for normal tissues. Subsequent repopulation commenced after 4 days and was equivalent to 1.8 Gy/day recovered dose, corresponding to a clonogenic cell number doubling time of 1.8 days. However, estimates of repair and repopulation may have been in error because the chronically hypoxic cells in this tumour alone have the ability to recover from potentially lethal damage (PLD) and so are more radioresistant than cells rendered acutely hypoxic by clamping. Because of this, even clamping off tumours at irradiation does not render all cell populations equally radioresistant, and so reoxygenation between fractions could result in an underestimate of repair and repopulation. Further, the differing sensitivity between acutely and chronically hypoxic cells renders the apparent OER a function of dose (i.e., oxygen not truly dose-modifying to chronically hypoxic cells). Consequently it is incorrect to assume a constant OER in order to compare repair in tumours irradiated under hypoxic conditions with that in normal tissues irradiated under aerobic conditions. (author)

Polar solvent modification of x ray induced potentially lethal damage in heterogeneous human colon tumor cells in vitro

International Nuclear Information System (INIS)

Arundel, C.M.; Leith, J.T.; Dexter, D.L.; Glicksman, A.S.

1984-01-01

Two subpopulations of tumor cells (clones A and D) obtained from a human colon adenocarcinoma were examined for their sensitivities to x-irradiation as unfed, early plateau phase cultures. Both the single dose survival curves and the kinetics of potentially lethal damage recovery (PLDR) were determined for the two tumor lines. Also, possible modification of PLDR by N,N-dimethylformamide (DMF), which has previously been shown to enhance the radiosensitivity of exponentially growing tumor cells, was investigated by adding DMF (0.8% v/v) to plateau phase cultures immediately after irradiation, and determining effects on the extent of PLDR. For non-DMF treated cells, the survival curve parameters of the diploid (clone D) and aneuploid (clone A) lines were very similar. Using initial survival levels of 3.5% (clone D) or 5.5% (clone A) to investigate PLDR, it was found that the increase in survival for clone D was 2.2, while the SFR for clone A was 1.6. DMF did not change either the kinetics or extent of PLDR in these two tumor lines when added to cultures immediately after irradiation. These results indicate that significant heterogeneity in PLDR exists between these closely related tumor subpopulations

The induction of mutation and recombination following UV irradiation during meiosis in Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Kelly, S.L.; Parry, J.M.

1983-01-01

Irradiation of yeast cultures with ultraviolet light at discrete stages during meiosis produces cyclic variations in sensitivity, i.e. cells are more sensitive to the lethal effects of UV light prior to entry into the meiotic DNA synthesis, and this corresponds to a peak of induction of point mutation. Cells become more resistant to both induced point mutation and lethality as they enter meiotic DNA synthesis, but become more sensitive again during spore formation. The induced level of intragenic recombination rises during the period of commitment ot recombination to a level indistinguishable from the full meiotic level of spontaneous intragenic recombination. Induced reciprocal recombination remains above the spontaneous level up to the point of commitment to sporulation. (orig.)

The induction of mutation and recombination following UV irradiation during meiosis in Saccharomyces cerevisiae.

Science.gov (United States)

Kelly, S L; Parry, J M

1983-03-01

Irradiation of yeast cultures with ultraviolet light at discrete stages during meiosis produces cyclic variations in sensitivity, i.e. cells are more sensitive to the lethal effects of UV light prior to entry into the meiotic DNA synthesis, and this corresponds to a peak of induction of point mutation. Cells become more resistant to both induced point mutation and lethality as they enter meiotic DNA synthesis, but become more sensitive again during spore formation. The induced level of intragenic recombination rises during the period of commitment to recombination to a level indistinguishable from the full meiotic level of spontaneous intragenic recombination. Induced reciprocal recombination remains above the spontaneous level up to the point of commitment to sporulation.

Effect of Modified Alkaline Supplementation on Syngenic Melanoma Growth in CB57/BL Mice.

Science.gov (United States)

Azzarito, Tommaso; Lugini, Luana; Spugnini, Enrico Pierluigi; Canese, Rossella; Gugliotta, Alessio; Fidanza, Stefano; Fais, Stefano

2016-01-01

Tumor extracellular acidity is a hallmark of malignant cancers. Thus, in this study we evaluated the effects of the oral administration of a commercially available water alkalizer (Basenpulver®) (BP) on tumor growth in a syngenic melanoma mouse model. The alkalizer was administered daily by oral gavage starting one week after tumor implantation in CB57/BL mice. Tumors were calipered and their acidity measured by in vivo MRI guided 31P MRS. Furthermore, urine pH was monitored for potential metabolic alkalosis. BP administration significantly reduced melanoma growth in mice; the optimal dose in terms of tolerability and efficacy was 8 g/l (p< 0.05). The in vivo results were supported by in vitro experiments, wherein BP-treated human and murine melanoma cell cultures exhibited a dose-dependent inhibition of tumor cell growth. This investigation provides the first proof of concept that systemic buffering can improve tumor control by itself and that this approach may represent a new strategy in prevention and/or treatment of cancers.

Effect of Modified Alkaline Supplementation on Syngenic Melanoma Growth in CB57/BL Mice.

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Tommaso Azzarito

Full Text Available Tumor extracellular acidity is a hallmark of malignant cancers. Thus, in this study we evaluated the effects of the oral administration of a commercially available water alkalizer (Basenpulver® (BP on tumor growth in a syngenic melanoma mouse model. The alkalizer was administered daily by oral gavage starting one week after tumor implantation in CB57/BL mice. Tumors were calipered and their acidity measured by in vivo MRI guided 31P MRS. Furthermore, urine pH was monitored for potential metabolic alkalosis. BP administration significantly reduced melanoma growth in mice; the optimal dose in terms of tolerability and efficacy was 8 g/l (p< 0.05. The in vivo results were supported by in vitro experiments, wherein BP-treated human and murine melanoma cell cultures exhibited a dose-dependent inhibition of tumor cell growth. This investigation provides the first proof of concept that systemic buffering can improve tumor control by itself and that this approach may represent a new strategy in prevention and/or treatment of cancers.

Interaction between x-irradiated plateau-phase bone marrow stromal cell lines and co-cultivated factor-dependent cell lines leading to leukemogenesis in vitro

International Nuclear Information System (INIS)

Naparstek, E.; Anklesaria, P.; FitzGerald, T.J.; Sakakeeny, M.A.; Greenberger, J.S.

1987-01-01

Plateau-phase mouse clonal bone marrow stromal cell lines D2XRII and C3H cl 11 produce decreasing levels of M-CSF (CSF-1), a specific macrophage progenitor cell humoral regulator, following X-irradiation in vitro. The decrease did not go below 40% of control levels, even after irradiation doses of 50,000 rad (500 Gy). In contrast, a distinct humoral regulator stimulating growth of GM-CSF/IL-3 factor-dependent (FD) hematopoietic progenitor cell lines was detected following radiation to doses above 2000 rad. This humoral factor was not detectable in conditioned medium from irradiated cells, weakly detected using factor-dependent target cell populations in agar overlay, and was prominently detected by liquid co-cultivation of factor-dependent cells with irradiated stromal cell cultures. Subclonal lines of FD cells, derived after co-cultivation revealed karyotypic abnormalities and induced myeloblastic tumors in syngeneic mice. Five-eight weeks co-cultivation was required for induction of factor independence and malignancy and was associated with dense cell to cell contact between FD cells and stromal cells demonstrated by light and electron microscopy. Increases in hematopoietic to stromal cell surface area, total number of adherent cells per flask, total non-adherent cell colonies per flask, and cumulative non-adherent cell production were observed after irradiation. The present data may prove very relevant to an understanding of the cell to cell interactions during X-irradiation-induced leukemia

Detection of endonuclease III- and 8-oxoguanine glycosylase-sensitive base modifications in γ-irradiated DNA and cells by the aldehyde reactive probe (ARP) assay

International Nuclear Information System (INIS)

Mohsin Ali, M.; Kurisu, Satofumi; Yoshioka, Yoshihiro; Terato, Hiroaki; Ohyama, Yoshihiko; Ide Hiroshi; Kubo, Kihei

2004-01-01

Ionizing radiation generates diverse DNA lesions that differentially induce cell death and mutations. In the present study, calf thymus DNA (400 μg/ml) and HeLa cells were irradiated by 60 Co γ-rays, and abasic (AP) sites and endonuclease (Endo) III- and 8-oxoguanine glycosylase (hOGG1)-sensitive base modifications in DNA were quantitated by the aldehyde reactive probe (ARP) assay. The irradiation of calf thymus DNA in phosphate buffer generated 91 Endo III- and 100 hOGG1-sensitive base modifications and 110 AP sites per 10 6 base pairs (bp) per Gy. The yield of the lesions in Tris buffer was 41- to 91-fold lower than that in phosphate, demonstrating a radioprotective effect of Tris. The HeLa cell chromosomal DNA contained 12 Endo III- and 3.8 hOGG1-sensitive base modifications and less than 1 AP sites per 10 6 bp as endogenous damage, and their level was increased by irradiation. The yields of the damage at 1 Gy (roughly equivalent to the lethal dose of HeLa cells [1.6-1.8 Gy]) were 0.13 Endo III, 0.091 hOGG1, and 0.065 AP sites per 10 6 bp, showing that irradiation with a lethal dose brought about only a marginal increase in base damage relative to an endogenous one. A comparison of the present data with those reported for DNA strand breaks supports the primary importance of double-strand breaks and clustered lesions as lethal damages formed by ionizing radiation. (author)

Effect of gamma irradiation on behaviour of Botrytis alii in vitro

International Nuclear Information System (INIS)

Arabi, I. E. D.; Charbaji, T.; Jawhar, M.

1998-07-01

The fungus Botrytis alii was irradiated with different dose of gamma radiation (0.8, 1, 1.5, 2, 3, 4, 5, 6 KGy) at different stages (spores and hyphae), the rate of hyphae irradiation. This growth was significantly reduced in the higher doses (43.2% at 3 KGy and 100% at 4 KGy) of the control the hyphae were recultured in unirradiated medium to confirm the result. The germination and growth of the spores were significantly slower of 4, 5, 6 KGy as compared with the doses of (0 to 3 KGy), and when recultured in the unirradiated medium, the inhibitory effect of (4, 5 KGy) and the lethal effect of (6 KGy) were confirmed. (author)

Clinical Symptoms and Histological Changes in Poecilia reticulata following Gamma-Ray Irradiation

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K. Beňová

2006-01-01

Full Text Available Lethality, food intake, clinical symptoms and terminal histological changes were followed after gamma-irradiation with doses of 10, 20, 30, 35 and 40 Gy in guppy, Poecilia reticulata. Clinical symptoms, food intake and longevity were also monitored in the progeny of fish irradiated with a dose of 10 Gy. In the first days after irradiation timidity and lethargy were observed. After doses of 30, 35 and 40 Gy, these symptoms were accompanied with anorexia. The most prominent clinical symptoms observed were emaciation, hampered breathing, exophthalmia and haemorrhages. Histological findings corresponded with these symptoms. In the fish irradiated with 10 or 20 Gy the progeny survived, after a dose of 30 Gy the progeny died within 24 hours after birth and after doses of 35 and 40 Gy dead progeny was born. The survival data provide an estimate of LD50/30 equal to 29 Gy. Higher relative mortality and more severe clinical symptoms were observed in females. The progeny of irradiated parent fish grew and survived for 3 months maximum.

Effect of gamma irradiation and moisture on microbiological load of sewage sludge

International Nuclear Information System (INIS)

Al-Bachir, M.; Al-Adawi, M. A.; Shamma, M.

2002-07-01

Concentrated municipal sewage sludge, stored for 2, 4, and 6 months, with moisture content of 2, 20, 40, 60, and 80% were exposed to doses of 0, 1, 2, 3, 4, and 5 kGy in a 60 Co package irradiator. Immediately after irradiation, total microbial count, bacterial pathogens in sewage sludge was determined. Techno-economic feasibility of irradiated sewage according to the moisture content in sewage sludge and the needed irradiation dose to eliminate pathogens was evaluated. The results indicated that, all tested sewage sludge sample, bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and e. coli, were detected. Used doses of gamma irradiation reduced the counts of microorganisms. D 1 0 of total count decreased with increasing the moisture level of sewage sludge. The lowest lethal dose for bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and e. coli is over 5 kGy and 1 kGy in air dried and watered sludge with more than 40% sewage sludge respectively, for samples taken at 2, 4 and 6 months of storage. (author)

The Use of Gamma Irradiation in the Sterilization of Streptomyces Colonizing the Tempra Paintings in Ancient Egyptian Tombs

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Akmal Ali SAKR

2013-09-01

Full Text Available Eight out of forty six Streptomyces strains from mural paintings at the Tell Basta and Tanis tombs were exposed to increasing doses (5, 10, 15, 20, 25kGy of gamma irradiation. These strains varied in their resistance profile. S. canarius was the most resistant to gamma irradiation doses, as it was totally eliminated at 25kGy, whereas S. chibaensis and S. albidofuscus resisted to 20kGy and S. ambofaciens resisted 15kGy. The other strains under investigation showed a lower resistance to gamma irradiation. Tricyclazole (5, 7, 10 µg/mL inhibited melanin production after gamma irradiation at doses lower than lethal dose. Gamma irradiation with the previous doses enhanced the chitinease activity of irradiated Streptomyces strains, but S. canarius was the exception. No color change was observed either for pigments or for binding media, after gamma irradiation at the same doses.

Role of vegetative nervous system in regulation of excretory function of irradiated dog stomach

International Nuclear Information System (INIS)

Kostesha, N.Ya.

1989-01-01

Dogs and rats were exposed to γ/neutron- and X-radiation. The anterior part of dog's stomach was exposed to 10 Gy and 13 Gy respectively; rats were subjected to whole-body irradiation with absolutely lethal doses. Prior to irradiation, various parts of the vegetative nervous system of both types of animals were switched off pharmocologically. In addition to clinical investigation of radiation sickness the excretory function of the stomach was studied by the excretion of intravenously injected neutral red. The switching-off of the parasympathetic nervous system prior to irradiation stabilized the excretory processes in the stomach, increased the resistance of animals, and, vice wersa, the switching-off of the sympathetic nervous system destabilized the excetory processes and decreased the resistance of the organism

Post-irradiation thymocyte regeneration after bone marrow transplantation

International Nuclear Information System (INIS)

Boersma, W.J.A.

1981-01-01

Bone marrow cells were separated according to buoyant density, velocity sedimentation and cell surface charge. Fractionated (C3H x AKR)F 1 bone marrow cells were transplanted into lethally-irradiated C3H recipients. In all fractions, the CFUs content and the capacity to restore the thymus cell population were determined. For all the physical parameters tested, thymocyte progenitor cells show the same distribution as CFUs. The relationship between number of thymocyte progenitor cells and number of CFUs is dependent on density. Bone marrow progenitors of PHA responsive cells are of low buoyant density and show a distribution which resembles the distribution of the progenitors of Thy 1 positive cells. After transplantation of large numbers of bone marrow cells into irradiated mice, no significant change in the CFUs content of the thymus was observed. (author)

Influence Analysis of Shell Material and Charge on Shrapnel Lethal Power

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Wang Lin

2015-01-01

Full Text Available To compare the shrapnel lethal power with different shell material and charge, LS-DYNA was used to numerically simulate four kinds of shrapnel lethal power. The shell material was 58SiMn, 50SiMnVB or 40Cr, whereas the charge was RL-F. And the shell material was 58SiMn, whereas the charge was TNT. The shell rupture process and lethal power test were analyzed. The results show that, the lethal power of RL-F charge increase by 25%, 45%, 14% compared with the TNT charge, whereas the shell material was 58SiMn, 50SiMnVB, 40Cr. And then the guarantee range and lethal power can be improved by using the high explosive and changing shell material, whereas the projectile shape coefficient is invariable.

Metacyclic promastigotes of Leishmania amazonensis selection using gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Bonetti, Franco C.; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Centro de Biologia Molecular]. E-mail: fbonetti@usp.br; Andrade Junior, Heitor Franco de [Instituto de Medicina Tropical de Sao Paulo, SP (Brazil). Lab. de Protozoologia

2005-07-01

Leishmania spp. causes a spectrum of human diseases, ranging from self-healing skin lesions to severe and lethal visceral disease. In previous work we demonstrated that the protein and nucleic acid metabolism and oxidative respiration were severely affected by irradiation, in a dose response way, but a small but representative fractions are relatively radio resistant, surviving after 800 Gy of {sup 60}Co irradiation. The best explanation could be a selection of metacyclic promastigotes. In these forms, the G0 state allows the adequate correction of DNA repair after the irradiation insult. In this work, we are looking for the ideal radiation dose to select the higher proportion of metacyclic forms of L.. (L.) amazonensis in culture. Parasites were grown in RPMI 1640 medium, plus 20% fetal calf serum, than they were irradiated with different doses ranging between 25 and 400 Gy. Parasites irradiated at 400 Gy infected, proportionally, more cells than parasites irradiated at other doses. To confirm this metacyclogenesis, a complement lysis assay was performed with 5, 10 and 20% of male guinea pig blood serum at 20 deg C for 3 hours, and parasites counted. Guinea pig serum a 10% promotes more lysis, with 200 Gy irradiated parasites being less affected, probably due to metacyclic selection. These preliminary results suggests that the ionizing radiation, specially between 200 and 400 Gy, could be a alternative tool for the selection of metacyclic forms of Leishmania amazonensis in culture. (a0011uth.

Metacyclic promastigotes of Leishmania amazonensis selection using gamma irradiation

International Nuclear Information System (INIS)

Bonetti, Franco C.; Nascimento, Nanci do; Andrade Junior, Heitor Franco de

2005-01-01

Leishmania spp. causes a spectrum of human diseases, ranging from self-healing skin lesions to severe and lethal visceral disease. In previous work we demonstrated that the protein and nucleic acid metabolism and oxidative respiration were severely affected by irradiation, in a dose response way, but a small but representative fractions are relatively radio resistant, surviving after 800 Gy of 60 Co irradiation. The best explanation could be a selection of metacyclic promastigotes. In these forms, the G0 state allows the adequate correction of DNA repair after the irradiation insult. In this work, we are looking for the ideal radiation dose to select the higher proportion of metacyclic forms of L.. (L.) amazonensis in culture. Parasites were grown in RPMI 1640 medium, plus 20% fetal calf serum, than they were irradiated with different doses ranging between 25 and 400 Gy. Parasites irradiated at 400 Gy infected, proportionally, more cells than parasites irradiated at other doses. To confirm this metacyclogenesis, a complement lysis assay was performed with 5, 10 and 20% of male guinea pig blood serum at 20 deg C for 3 hours, and parasites counted. Guinea pig serum a 10% promotes more lysis, with 200 Gy irradiated parasites being less affected, probably due to metacyclic selection. These preliminary results suggests that the ionizing radiation, specially between 200 and 400 Gy, could be a alternative tool for the selection of metacyclic forms of Leishmania amazonensis in culture. (author)

Lethal and Sub-lethal Effects of Four Insecticides on the Aphidophagous Coccinellid Adalia bipunctata (Coleoptera: Coccinellidae).

Science.gov (United States)

Depalo, Laura; Lanzoni, Alberto; Masetti, Antonio; Pasqualini, Edison; Burgio, Giovanni

2017-12-05

Conventional insecticide assays, which measure the effects of insecticide exposure on short-term mortality, overlook important traits, including persistence of toxicity or sub-lethal effects. Therefore, such approaches are especially inadequate for prediction of the overall impact of insecticides on beneficial arthropods. In this study, the side effects of four modern insecticides (chlorantraniliprole, emamectin benzoate, spinosad, and spirotetramat) on Adalia bipunctata (L.) (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by exposition on treated potted plants. In addition to investigation of acute toxicity and persistence of harmful activity in both larvae and adults of A. bipunctata, demographic parameters were evaluated, to provide a comprehensive picture of the nontarget effects of these products. Field doses of the four insecticides caused detrimental effects to A. bipunctata; but in different ways. Overall, spinosad showed the best toxicological profile among the products tested. Emamectin benzoate could be considered a low-risk insecticide, but had high persistence. Chlorantraniliprole exhibited lethal effects on early instar larvae and adults, along with a long-lasting activity, instead spirotetramat showed a low impact on larval and adult mortality and can be considered a short-lived insecticide. However, demographic analysis demonstrated that chlorantraniliprole and spirotetramat caused sub-lethal effects. Our findings highlight that sole assessment of mortality can lead to underestimation of the full impact of pesticides on nontarget insects. Demographic analysis was demonstrated to be a sensitive method for detection of the sub-lethal effects of insecticides on A. bipunctata, and this approach should be considered for evaluation of insecticide selectivity. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Irradiation of liquid manure for the purpose of utilization in agriculture

International Nuclear Information System (INIS)

Simon, J.; Gleria, M. di; Szemeredi, Gy.

1980-01-01

The authors give an account of the use of ionizing radiation for disinfection of swine liquid manure. The most common representatives of pathogenic and facultative pathogenic microorganisms of swine liquid manure have been irradiated and their sensitivity to different doses of 60 Co has been examined. The microorganisms proved to be more resistant to irradiation in culture media than in swine liquid manure, where most of the studied bacteria were killed by radiation dose of 4 kGy. However, a very high resistance has been found at the saprophytic and pathogenic mycobacteria and at the spore containing Clostridium perfringens having required a lethal dose of 10 and 15 kGy respectively. After radiation-treatment the liquid manure can be used in agriculture for irrigation and it can be recycled to the stall cleaning procedures. The use of irradiated liquid manure as a possible animal food is also discussed. (Auth.)

Maintenance of host leukocytes in peripheral immune compartments following lethal irradiation and bone marrow reconstitution: implications for graft versus host disease.

Science.gov (United States)

Staley, Elizabeth M; Tanner, Scott M; Daft, Joseph G; Stanus, Andrea L; Martin, Steven M; Lorenz, Robin G

2013-03-01

Bone marrow reconstitution is utilized as a tool for disease treatment and as a research technique to elucidate the function of bone marrow derived cells. Clinically successful engraftment is indicated by the development of a functioning immune repertoire. In research, reconstitution is considered successful if >85% of splenic leukocytes are of donor origins. Previous work suggests that splenic reconstitution may not be indicative of reconstitution in the mucosa. We sought to evaluate mucosal reconstitution in animals following a standard bone marrow eradication and reconstitution technique. Bone marrow was harvested from adult B6.SJL donor mice (CD45.1) and injected via either the retro-orbital or intraperitoneal route into lethally irradiated B6 (CD45.2) adult or neonatal recipients respectively. The expression of CD45 by flow cytometry was used to calculate reconstitution with respect to immune compartment and cell type. In reconstituted adult animals 93.2±1.5% of splenic leukocytes expressed the donor CD45.1 antigen thus meeting the standard definition of reconstitution, however only 58.6±13.6% of intestinal lamina propria lymphocytes and 52.4±16.0% of intestinal intraepithelial lymphocytes were of donor origin, confirming splenic reconstitution fails to represent peripheral immune reconstitution. T-cells in the gastrointestinal tract are the most poorly reconstituted, while B-cells appear to be almost universally replaced by donor cells. The inadequate mucosal reconstitution was not corrected by evaluating later time points or by performing the bone marrow transfer during the neonatal period. This demonstration that substantial host T-cells remain in the intestinal mucosa after a "successful" bone marrow transplantation should cause a re-evaluation of data from research bone marrow chimera experiments, as well as the mechanisms for complications after clinical bone marrow transplantation. Copyright © 2013 Elsevier B.V. All rights reserved.

Back to the future: revisiting HIV-1 lethal mutagenesis

Science.gov (United States)

Dapp, Michael J.; Patterson, Steven E.; Mansky, Louis M.

2012-01-01

The concept of eliminating HIV-1 infectivity by elevating the viral mutation rate was first proposed over a decade ago, even though the general concept had been conceived earlier for RNA viruses. Lethal mutagenesis was originally viewed as a novel chemotherapeutic approach for treating HIV-1 infection in which use of a viral mutagen would over multiple rounds of replication lead to the lethal accumulation of mutations, rendering the virus population non infectious – known as the slow mutation accumulation model. There have been limitations in obtaining good efficacy data with drug leads, leaving some doubt into clinical translation. More recent studies of the APOBEC3 proteins as well as new progress in the use of nucleoside analogs for inducing lethal mutagenesis have helped to refocus attention on rapid induction of HIV-1 lethal mutagenesis in a single or limited number of replication cycles leading to a rapid mutation accumulation model. PMID:23195922

Perinatal-lethal Gaucher disease presenting as hydrops fetalis.