Stimulation of islet cell proliferation enhances pancreatic ductal carcinogenesis in the hamster model.

PubMed Central

Pour, P. M.; Kazakoff, K.

1996-01-01

Previous studies have shown that some N-nitrosobis (2-oxopropyl)amine (BOP)-induced ductal/ductular pancreatic cancers in the hamster model develop within islets and that streptozotocin (SZ) pretreatment that caused islet degeneration and atrophy inhibits pancreatic cancer induction. Hence, it appears that in this model islets play a significant role in exocrine pancreatic carcinogenesis. To examine whether stimulation of islet cell proliferation (nesidioblastosis) enhances pancreatic exocrine cancer development, we tested the effect of the pancreatic carcinogen BOP in hamsters after induction of nesidioblastosis by cellophane wrapping. Before wrapping, hamsters were treated with SZ to inhibit pancreatic tumor induction in the unwrapped pancreatic tissues. Control groups with a wrapped pancreas did not receive SZ. Six weeks after SZ treatment, all hamsters were treated with BOP (10 mg/kg body weight) weekly for 10 weeks and the experiment was terminated 38 weeks after the last BOP treatment. Many animals recovered from their diabetes at the time when BOP was injected and many more after BOP treatment. Only nine hamsters remained diabetic until the end of the experiment. Both SZ-treated and control groups developed proliferative and malignant pancreatic ductal-type lesions primarily in the wrapped area (47%) but less frequently in the larger segments of the pancreas, including the splenic lobe (34%), gastric lobe (13%), and duodenal lobe (6%). Only a few lesions developed in the unwrapped pancreatic region of nine diabetic hamsters with atrophic islets, whereas seven of these hamsters had tumors in the wrapped area. Histologically, most tumors appeared to originate from islets, many invasive carcinomas had foci of islets, and some tumor cells showed reactivity with anti-insulin. The results show that, in the BOP hamster model, islets are the site of formation of the major fraction of exocrine pancreatic cancer and that induction of nesidioblastosis enhances

Mutation and repair in an ultraviolet-sensitive Chinese hamster ovary cell line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wood, R.D.

1981-11-01

An ultraviolet (UV) light-sensitive mutant of Chinese hamster ovary cells (CHO) has been isolated and characterized with respect to a number of post-irradiation responses. The UV-sensitive mutant, termed 43-3B, has the same growth rate and chromosome number as the wild-type CHO-9. 43-3B is hypersensitive to the lethal effects of UV light (D/sub 0/ of 0.3 J/m/sup 2/ as compared to 3.2 J/m/sup 2/ for the wild-type). A marked UV-hypermutability is observed in 43-3B as compared to the wild-type, as measured with markers for induced resistance to 6-thioguanine, ouabain, and diphtheria toxin. A factor of 38 to 65 more mutations aremore » induced per unit fluence in 43-3B than in CHO-9. The UV-sensitive mutant is also sensitive to killing by simulated solar light, although the D/sub 0/ ratio is not as great as for germicidal UV. 43-3B exhibits only about 17% of the wild-type level of UV-stimulated DNA repair synthesis, as measured by autoradiography of G/sub 1/ phase cells. A much reduced ability to recover control rates of semiconservative DNA synthesis after UV irradiation was observed in the repair-deficient 43-3B cell line. Recovery of colony-forming ability between fractionated UV exposures was observed in the wild-type CHO-9, but little recovery was seen in 43-3B. The present investigation demonstrates that a sensitive/wild-type pair of CHO cell lines can be used in comparative studies to determine the involvement of repair in a wide range of post-irradiation phenomena.« less

T Cells Are Not Required for Pathogenesis in the Syrian Hamster Model of Hantavirus Pulmonary Syndrome ▿

PubMed Central

Hammerbeck, Christopher D.; Hooper, Jay W.

2011-01-01

Andes virus (ANDV) is associated with a lethal vascular leak syndrome in humans termed hantavirus pulmonary syndrome (HPS). In hamsters, ANDV causes a respiratory distress syndrome closely resembling human HPS. The mechanism for the massive vascular leakage associated with HPS is poorly understood; however, T cell immunopathology has been implicated on the basis of circumstantial and corollary evidence. Here, we show that following ANDV challenge, hamster T cell activation corresponds with the onset of disease. However, treatment with cyclophosphamide or specific T cell depletion does not impact the course of disease or alter the number of surviving animals, despite significant reductions in T cell number. These data demonstrate, for the first time, that T cells are not required for hantavirus pathogenesis in the hamster model of human HPS. Depletion of T cells from Syrian hamsters did not significantly influence early events in disease progression. Moreover, these data argue for a mechanism of hantavirus-induced vascular permeability that does not involve T cell immunopathology. PMID:21775442

Survival of Chinese Hamster Ovary Cells Following Ultrahigh Dose Rate Electron and Bremsstrahlung Radiation

DTIC Science & Technology

1990-04-01

and a stepped lead flattening filter. The electron energy used for these studies was 13 MeV. Dosimetry was performed by the Health Physics Division...VolI LJSAFSAPA-TR-90-4 AD-A222 722 SURVIVAL OF CHINESE HAMSTER OVARY CELLS FOLLOWING ULTRAHIGH DOSE RATE ELECTRON AND BREMISSTRAHLUNG RADIATION...Include Security ;a!. iatcn) Survival of Chinese Hamster Ovary Cells Following Ultrahigh Dose Rate Electron and Bremsstrahlung Radiation 12 PERSONAL

Treating cell culture media with UV irradiation against adventitious agents: minimal impact on CHO performance.

PubMed

Yen, Sandi; Sokolenko, Stanislav; Manocha, Bhavik; Blondeel, Eric J M; Aucoin, Marc G; Patras, Ankit; Daynouri-Pancino, Farnaz; Sasges, Michael

2014-01-01

Sterility of cell culture media is an important concern in biotherapeutic processing. In large scale biotherapeutic production, a unit contamination of cell culture media can have costly effects. Ultraviolet (UV) irradiation is a sterilization method effective against bacteria and viruses while being non-thermal and non-adulterating in its mechanism of action. This makes UV irradiation attractive for use in sterilization of cell culture media. The objective of this study was to evaluate the effect of UV irradiation of cell culture media in terms of chemical composition and the ability to grow cell cultures in the treated media. The results showed that UV irradiation of commercial cell culture media at relevant disinfection doses impacted the chemical composition of the media with respect to several carboxylic acids, and to a minimal extent, amino acids. The cumulative effect of these changes, however, did not negatively influence the ability to culture Chinese Hamster Ovary cells, as evaluated by cell viability, growth rate, and protein titer measurements in simple batch growth compared with the same cells cultured in control media exposed to visible light. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers.

Early effect of boron neutron capture therapy mediated by boronophenylalanine (BPA-BNCT) on mast cells in premalignant tissue and tumors of the hamster cheek pouch.

PubMed

Aromando, Romina F; Trivillin, Verónica A; Heber, Elisa M; Pozzi, Emiliano; Schwint, Amanda E; Itoiz, María E

2010-05-01

Mast cell (MC) activation in the hamster cheek pouch cancerization model is associated with the increase in tumor cell proliferation, mediated in turn by tryptase, a protease released from mast cell granules after activation. Tryptase induces tumor cell proliferation through the activation of PAR-2 (protease activated receptor-2) on the plasma membrane of carcinoma cells. The therapeutic success of boron neutron capture therapy mediated by boronophenylalanine (BPA-BNCT) in tumor control in the hamster cheek pouch oral cancer model has been previously reported by our laboratory. Early effects of BPA-BNCT on tumors of the hamster cheek pouch include a reduction in DNA-synthesis with the concomitant decrease in the proliferation of malignant cells. The aim of the present study was to investigate the early histological changes in mast cells after BPA-BNCT in tumors and premalignant tissue of the hamster cheek pouch. Tumor-bearing pouches were treated with BPA-BNCT or beam only (neutron irradiation without prior administration of the boron compound) and sacrificed 1day after treatment. The samples were fixed in Carnoy fixative and stained with alcian blue-safranin to identify all the populations of mast cells. Total, active and inactive mast cells (MC) were counted in the connective tissue and the adventitious tissue underlying the pouch wall and at the base of the tumors in pouches treated with BPA-BNCT, in keeping with a previously described technique. BPA-BNCT induced a marked reduction in the total number of mast cells in the pouch (p<0.05). This reduction in the total number of mast cells was due to a reduction in mast cells at the base of the tumor (p<0.005) and it occurred at the expense of the active mast cells (p<0.05). A slight reduction that did not reach statistical significance also occurred in the amount of mast cells in the pouch wall (that corresponds to the premalignant tissue in tumor-bearing pouches), and in the adventitious tissue. In this case the

Inhaled ozone as a mutagen. II - Effect on the frequency of chromosome aberrations observed in irradiated Chinese hamsters.

NASA Technical Reports Server (NTRS)

Zelac, R. E.; Cromroy, H. L.; Bolch, W. E., Jr.; Dunavant, B. G.; Bevis, H. A.

1971-01-01

Exposure-adjusted break frequencies for chromosome aberrations produced in Chinese hamster circulating blood lymphocytes were the quantitative indicator of damage from 5 hrs of exposure to X-radiation and/or to ozone. Radiation produced 5.51 x 0.0001 breaks/cell rad for cells withdrawn 2 weeks after exposure, a reasonable value when compared with data from in vivo exposure of human lymphocytes and Chinese hamster bone marrow cells. Animals exposed to the two agents simultaneously exhibited more than 70% of the total breaks anticipated assuming the expected equal contributions to be additive. Extending to humans, at presently permitted levels, exposure to ozone would be much more detrimental than exposure to radiati*n.

Irradiation chamber and sample changer for biological samples

NASA Astrophysics Data System (ADS)

Kraft, G.; Daues, H. W.; Fischer, B.; Kopf, U.; Liebold, H. P.; Quis, D.; Stelzer, H.; Kiefer, J.; Schöpfer, F.; Schneider, E.; Weber, K.; Wulf, H.; Dertinger, H.

1980-01-01

This paper describes an irradiation system with which living cells of different origin are irradiated with heavy ion beams (18⩽ Z⩽92) at energies up to 10 MeV/amu. The system consists of a beam monitor connected to the vacuum system of the accelerator and the irradiation chamber, containing the biological samples under atmospheric pressure. The requirements and aims of the set up are discussed. The first results with saccharomyces cerevisiae and Chinese Hamster tissue cells are presented.

Relative biological effectiveness of accelerated heavy ions for induction of morphological transformation in Syrian hamster embryo cells.

PubMed

Han, Z B; Suzuki, H; Suzuki, F; Suzuki, M; Furusawa, Y; Kato, T; Ikenaga, M

1998-09-01

Syrian hamster embryo cells were used to study the morphological transformation induced by accelerated heavy ions with different linear energy transfer (LET) ranging from 13 to 400 keV/micron. Exponentially growing cells were irradiated with 12C or 28Si ion beams generated by the Heavy Ion Medical Accelerator in Chiba (HIMAC), then inoculated to culture dishes. Morphologically altered colonies were scored as transformants. Over the LET range examined, the frequency of transformation induced by the heavy ions increased sharply at very low doses no greater than 5 cGy. The relative biological effectiveness (RBE) of the heavy ions relative to X-rays first increased with LET, reached a maximum value of about 7 at 100 keV/micron, then decreased with the further increase of LET. Our findings confirmed that high LET heavy ions are much more effective than X-rays for the induction of in vitro cell transformation.

Prevention of Simian Virus 40 Tumors by Hamster Fetal Tissue: Influence of Parity Status of Donor Females on Immunogenicity of Fetal Tissue and on Immune Cell Cytotoxicity

PubMed Central

Girardi, Anthony J.; Reppucci, Phyllis; Dierlam, Peggy; Rutala, William; Coggin, Joseph H.

1973-01-01

Fetal tissue from primiparous hamsters prevented simian virus 40 (SV40) tumorigenesis in male hamsters, whereas fetal tissue from multiparous hamsters did not. The parity status of normal (uninoculated) hamsters also influenced the cytotoxicity of their lymphoid cells against tumor cells. Lymph node cells from nonpregnant primiparous and multiparous animals were cytotoxic in microcytotoxicity tests against SV40, polyoma, and adenovirus 7 tumor cells, but were not active against control BHK cells. Lymph node cells from virgin female donors were inactive. Peritoneal exudate cells from these donors reacted in similar fashion against SV40 tumor cells in vitro and in adoptive transfer tests in vivo. However, the cytotoxicity of peritoneal exudate cells from multiparous hamsters was greatly reduced during pregnancy, a time when noncytotoxic humoral antibody reactive with surface antigen of SV40 tumor cells is present. This humoral antibody is not detected during first pregnancy, and peritoneal exudate cells obtained from pregnant primiparous hamsters demonstrated a high degree of cytotoxicity. PMID:4346032

Characteristics of the uridine uptake system in normal and polyoma transformed hamster embryo cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lemkin, J.A.

1973-01-01

The lability of the uridine uptake system in the normal and polyoma transformed hamster embryo fibroblast was studied. The major areas investigated were: the kinetic parameters of uridine transport, a comparison of changes in cellular ATP content by factors which modulate uridine uptake, and a comparison of the qualitative and quantitative effects of the same modulating agent on uridine transport, cell growth, and cellular ATP content. Uridine uptake into cells in vitro was examined using tritiated uridine as a tracer to measure the amount of uridine incorporated into the acid soluble and acid-insoluble fractions of the cells studied. The ATPmore » content of the cells was determined by the firefly bioluminescence method. It was found that the K/sub t/ for uridine uptake into the normal hamster embryo cell and two polyoma transformed hamster embryo cell lines was identical. However, the V/sub max/ for uridine transport was higher in both polyoma transformed cell lines. Furthermore, the K/sub t/ in both the normal and transformed cell cultured in serum-less or serum-containing media was identical, although the V/sub max/ was higher in the serum-stimulated cell in both the normal and transformed cell. Stimulation of the normal cell with adenosine produced a different K/sub t/ for uridine transport. Preliminary investigations have demonstrated that treatment of the polyoma transformed with adenosine also induces a different K/sub t/ (not shown). The K/sub i/ for phloretin inhibition in serum-less and serum-stimulated normal and polyoma transformed cells was found to be identical in each case.« less

Replication of adeno-associated virus in cells irradiated with UV light at 254 nm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yakobson, B.; Hrynko, T.A.; Peak, M.J.

1989-03-01

Irradiation of simian virus 40 (ori mutant)-transformed Chinese hamster embryo cells (OD4 line) with UV light induced a cellular capacity which supported a full cycle of helper-independent adeno-associated virus replication. Monochromatic UV light at 254 nm was about 1,000-fold more effective than UV light at 313 nm, indicating that cellular nucleic acid is the primary chromophore in the UV-induced process leading to permissiveness for adeno-associated virus replication. The UV irradiation and the infection could be separated for up to 12 h without substantial loss of permissiveness. During this time interval, the induction process was partly sensitive to cycloheximide, suggesting amore » requirement for de novo protein synthesis.« less

Histopathology of Lyme arthritis in LSH hamsters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hejka, A.; Schmitz, J.L.; England, D.M.

1989-05-01

The authors studied the histopathologic evolution of arthritis in nonirradiated and irradiated hamsters infected with Borrelia burgdorferi. Nonirradiated hamsters injected in the hind paws with B. burgdorferi developed an acute inflammatory reaction involving the synovium, periarticular soft tissues, and dermis. This acute inflammatory reaction was short-lived and was replaced by a mild chronic synovitis as the number of detectable spirochetes in the synovium, periarticular soft tissues, and perineurovascular areas diminished. Exposing hamsters to radiation before inoculation with B. burgdorferi exacerbated and prolonged the acute inflammatory phase. Spirochetes also persisted longer in the periarticular soft tissues. A major histopathologic finding wasmore » destructive and erosive bone changes of the hind paws, which resulted in deformation of the joints. These studies should be helpful in defining the immune mechanism participating in the onset, progression, and resolution of Lyme arthritis.« less

Transformation of Primary Hamster Brain Cells with JC Virus and Its DNA

PubMed Central

Frisque, R. J.; Rifkin, D. B.; Walker, D. L.

1980-01-01

We transformed primary hamster brain cells with four isolates of JC virus and JC virus DNA. Several properties of these transformants were characterized and compared to those of simian virus 40 transformants isolated under identical conditions. Images PMID:6251275

Hamster and Murine Models of Severe Destructive Lyme Arthritis

PubMed Central

Munson, Erik; Nardelli, Dean T.; Du Chateau, Brian K.; Callister, Steven M.; Schell, Ronald F.

2012-01-01

Arthritis is a frequent complication of infection in humans with Borrelia burgdorferi. Weeks to months following the onset of Lyme borreliosis, a histopathological reaction characteristic of synovitis including bone, joint, muscle, or tendon pain may occur. A subpopulation of patients may progress to a chronic, debilitating arthritis months to years after infection which has been classified as severe destructive Lyme arthritis. This arthritis involves focal bone erosion and destruction of articular cartilage. Hamsters and mice are animal models that have been utilized to study articular manifestations of Lyme borreliosis. Infection of immunocompetent LSH hamsters or C3H mice results in a transient synovitis. However, severe destructive Lyme arthritis can be induced by infecting irradiated hamsters or mice and immunocompetent Borrelia-vaccinated hamsters, mice, and interferon-gamma- (IFN-γ-) deficient mice with viable B. burgdorferi. The hamster model of severe destructive Lyme arthritis facilitates easy assessment of Lyme borreliosis vaccine preparations for deleterious effects while murine models of severe destructive Lyme arthritis allow for investigation of mechanisms of immunopathology. PMID:22461836

Effect of Antiviral Agents in Equine Abortion Virus-Infected Hamsters1

PubMed Central

Lieberman, Melvin; Pascale, Andrea; Schafer, Thomas W.; Came, Paul E.

1972-01-01

Equine abortion virus, a member of the herpesvirus group, produces a lethal infection in hamsters. With this system, the protective effect of certain inhibitors of deoxyribonucleic acid viruses, inducers of interferon and exogenous interferon, was evaluated. Of the various agents studied, 9-β-d-arabinofuranosyladenine markedly suppressed mortality, and 5-iodo-2′-deoxyuridine, distamycin A, and N-ethylisatin β-thiosemicarbazone were inactive. Of the inducers tested, statolon, ultraviolet-irradiated Newcastle disease virus, and polyriboinosinic:polyribocytidylic acid (poly I:C) were protective, and endotoxin, polyacrylic acid, and polymethacrylic acid did not protect. Administration of exogenous interferon did not afford protection. Statolon and ultraviolet-irradiated Newcastle disease virus induced circulating interferon in hamsters, whereas poly I:C, endotoxin, and polyacrylic acid did not produce interferon. Because of the severity of the disease produced in hamsters by equine abortion virus, lack of protective activity by an agent in this system should not preclude possible efficacy against other members of the herpesvirus group. PMID:4376907

Differential response of two cell lines sequentially irradiated with low X-ray doses.

PubMed

Güerci, A M; Dulout, F N; Grillo, C A; Seoane, A I

2005-05-01

An experiment was designed to compare the effect of repeated low doses of X-rays in two different cell lines: one transformed, epithelial like and aneuploid Chinese hamster ovary K-1 (CHO-K1); the other originated from a human primary culture, fibroblast, diploid and non-transformed, MRC-5. CHO and MRC-5 cells were cultured for 14 or eight passages, respectively. Irradiation was performed once per passage when cells were in the quiescent state (90 - 95% in G1/G0). Cells were exposed to 10.0 mSv X-ray doses. Ionizing radiation did not induce apoptosis or necrosis in the exposed CHO cell population. Significant increases of low-level damaged cells (degrees 1 and 2) were found for the 14 cycles of radiation when compared with controls, except for the first irradiation cycle. No significant increases in the frequency of cells with severe damage were observed. The frequency of MRC-5 cells with low-level damage increased significantly when compared with controls for radiation cycles seven and eight. Significant increases of apoptosis, necrosis and severe damage were found only for the highest dose. Transformed and non-transformed cell types responded differently to direct and indirect damage using low-dose repeat exposures to ionizing radiation. Though more investigation is needed to understand the mechanisms of radiation effects in chronic low-dose-exposed cell populations, cellular type should be taken into account in the design of in vitro experiments for understanding low-dose-irradiation effects.

Crocidolite asbestos and SV40 are cocarcinogens in human mesothelial cells and in causing mesothelioma in hamsters

PubMed Central

Kroczynska, Barbara; Cutrone, Rochelle; Bocchetta, Maurizio; Yang, Haining; Elmishad, Amira G.; Vacek, Pamela; Ramos-Nino, Maria; Mossman, Brooke T.; Pass, Harvey I.; Carbone, Michele

2006-01-01

Only a fraction of subjects exposed to asbestos develop malignant mesothelioma (MM), suggesting that additional factors may render some individuals more susceptible. We tested the hypothesis that asbestos and Simian virus (SV40) are cocarcinogens. Asbestos and SV40 in combination had a costimulatory effect in inducing ERK1/2 phosphorylation and activator protein-1 (AP-1) activity in both primary Syrian hamster mesothelial cells (SHM) and primary human mesothelial cells (HM). Ap-1 activity caused the expression and activation of matrix metalloprotease (MMP)-1 and MMP-9, which in turn led to cell invasion. Experiments using siRNA and chemical inhibitors confirmed the specificity of these results. The same effects were observed in HM and SHM. Experiments in hamsters showed strong cocarcinogenesis between asbestos and SV40: SV40 did not cause MM, asbestos caused MM in 20% of hamsters, and asbestos and SV40 together caused MM in 90% of hamsters. Significantly lower amounts of asbestos were sufficient to cause MM in animals infected with SV40. Our results indicate that mineral fibers and viruses can be cocarcinogens and suggest that lower amounts of asbestos may be sufficient to cause MM in individuals infected with SV40. PMID:16966607

Impact of Dissolved Oxygen during UV-Irradiation on the Chemical Composition and Function of CHO Cell Culture Media.

PubMed

Meunier, Sarah M; Todorovic, Biljana; Dare, Emma V; Begum, Afroza; Guillemette, Simon; Wenger, Andrew; Saxena, Priyanka; Campbell, J Larry; Sasges, Michael; Aucoin, Marc G

2016-01-01

Ultraviolet (UV) irradiation is advantageous as a sterilization technique in the biopharmaceutical industry since it is capable of targeting non-enveloped viruses that are typically challenging to destroy, as well as smaller viruses that can be difficult to remove via conventional separation techniques. In this work, we investigated the influence of oxygen in the media during UV irradiation and characterized the effect on chemical composition using NMR and LC-MS, as well as the ability of the irradiated media to support cell culture. Chemically defined Chinese hamster ovary cell growth media was irradiated at high fluences in a continuous-flow UV reactor. UV-irradiation caused the depletion of pyridoxamine, pyridoxine, pyruvate, riboflavin, tryptophan, and tyrosine; and accumulation of acetate, formate, kynurenine, lumichrome, and sarcosine. Pyridoxamine was the only compound to undergo complete degradation within the fluences considered; complete depletion of pyridoxamine was observed at 200 mJ/cm2. Although in both oxygen- and nitrogen-saturated media, the cell culture performance was affected at fluences above 200 mJ/cm2, there was less of an impact on cell culture performance in the nitrogen-saturated media. Based on these results, minimization of oxygen in cell culture media prior to UV treatment is recommended to minimize the negative impact on sensitive media.

Impact of Dissolved Oxygen during UV-Irradiation on the Chemical Composition and Function of CHO Cell Culture Media

PubMed Central

Meunier, Sarah M.; Todorovic, Biljana; Dare, Emma V.; Begum, Afroza; Guillemette, Simon; Wenger, Andrew; Saxena, Priyanka; Campbell, J. Larry; Sasges, Michael; Aucoin, Marc G.

2016-01-01

Ultraviolet (UV) irradiation is advantageous as a sterilization technique in the biopharmaceutical industry since it is capable of targeting non-enveloped viruses that are typically challenging to destroy, as well as smaller viruses that can be difficult to remove via conventional separation techniques. In this work, we investigated the influence of oxygen in the media during UV irradiation and characterized the effect on chemical composition using NMR and LC-MS, as well as the ability of the irradiated media to support cell culture. Chemically defined Chinese hamster ovary cell growth media was irradiated at high fluences in a continuous-flow UV reactor. UV-irradiation caused the depletion of pyridoxamine, pyridoxine, pyruvate, riboflavin, tryptophan, and tyrosine; and accumulation of acetate, formate, kynurenine, lumichrome, and sarcosine. Pyridoxamine was the only compound to undergo complete degradation within the fluences considered; complete depletion of pyridoxamine was observed at 200 mJ/cm2. Although in both oxygen- and nitrogen-saturated media, the cell culture performance was affected at fluences above 200 mJ/cm2, there was less of an impact on cell culture performance in the nitrogen-saturated media. Based on these results, minimization of oxygen in cell culture media prior to UV treatment is recommended to minimize the negative impact on sensitive media. PMID:26975046

Synergetic cholesterol-lowering effects of main alkaloids from Rhizoma Coptidis in HepG2 cells and hypercholesterolemia hamsters.

PubMed

Kou, Shuming; Han, Bing; Wang, Yue; Huang, Tao; He, Kai; Han, Yulong; Zhou, Xia; Ye, Xiaoli; Li, Xuegang

2016-04-15

Hyperlipidemia contributes to the progression of cardiovascular diseases. Main alkaloids from Rhizoma Coptidis including berberine (BBR), coptisine (COP), palmatine (PAL), epiberberine (EPI) and jatrorrhizine (JAT), improved dyslipidemia in hypercholesterolemic hamsters to a different degree. In this study, HepG2 cells and hypercholesterolemic hamsters were used to investigate the synergetic cholesterol-lowering efficacy of these five main alkaloids. The cellular lipid and cholesterol accumulation and in HepG2 cells were evaluated by Oil Red O staining and HPLC analysis. LDL receptor, 3-Hydroxy-3-methylglutaryl CoA reductase (HMGCR) and cholesterol 7-alpha-hydroxylase (CYP7A1) that involving cholesterol metabolism in HepG2 cells were measured by qRT-PCR, western blot and immunofluorescence analysis. The serum profiles including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c), as well as TC and total bile acids (TBA) of feces in hypercholesterolemic hamsters were also measured. As compared to single alkaloids, the combination of five main alkaloids (COM) reduced the lipid and cholesterol accumulation in HepG2 cells more effectively and performed an advantageous effect on controlling TC, TG, LDL-c and HDL-c in hypercholesterolemic hamsters. More effective reduction of TBA and TC levels in feces of hamsters were achieved after the administration of COM. These effects were derived from the up-regulation of LDL receptor and CYP7A1, as well as HMGCR downregulation. Our results demonstrated that COM showed a synergetic cholesterol-lowering efficacy, which was better than single alkaloids and it might be considered as a potential therapy for hypercholesterolemia. Copyright © 2016 Elsevier Inc. All rights reserved.

Inhibitory effect of vitamin D-binding protein-derived macrophage activating factor on DMBA-induced hamster cheek pouch carcinogenesis and its derived carcinoma cell line.

PubMed

Toyohara, Yukiyo; Hashitani, Susumu; Kishimoto, Hiromitsu; Noguchi, Kazuma; Yamamoto, Nobuto; Urade, Masahiro

2011-07-01

This study investigated the inhibitory effect of vitamin D-binding protein-derived macrophage-activating factor (GcMAF) on carcinogenesis and tumor growth, using a 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced hamster cheek pouch carcinogenesis model, as well as the cytocidal effect of activated macrophages against HCPC-1, a cell line established from DMBA-induced cheek pouch carcinoma. DMBA application induced squamous cell carcinoma in all 15 hamsters of the control group at approximately 10 weeks, and all 15 hamsters died of tumor burden within 20 weeks. By contrast, 2 out of the 14 hamsters with GcMAF administration did not develop tumors and the remaining 12 hamsters showed a significant delay of tumor development for approximately 3.5 weeks. The growth of tumors formed was significantly suppressed and none of the hamsters died within the 20 weeks during which they were observed. When GcMAF administration was stopped at the 13th week of the experiment in 4 out of the 14 hamsters in the GcMAF-treated group, tumor growth was promoted, but none of the mice died within the 20-week period. On the other hand, when GcMAF administration was commenced after the 13th week in 5 out of the 15 hamsters in the control group, tumor growth was slightly suppressed and all 15 hamsters died of tumor burden. However, the mean survival time was significantly extended. GcMAF treatment activated peritoneal macrophages in vitro and in vivo, and these activated macrophages exhibited a marked cytocidal effect on HCPC-1 cells. Furthermore, the cytocidal effect of activated macrophages was enhanced by the addition of tumor-bearing hamster serum. These findings indicated that GcMAF possesses an inhibitory effect on tumor development and growth in a DMBA-induced hamster cheek pouch carcinogenesis model.

Inhibitory effect of vitamin D-binding protein-derived macrophage activating factor on DMBA-induced hamster cheek pouch carcinogenesis and its derived carcinoma cell line

PubMed Central

TOYOHARA, YUKIYO; HASHITANI, SUSUMU; KISHIMOTO, HIROMITSU; NOGUCHI, KAZUMA; YAMAMOTO, NOBUTO; URADE, MASAHIRO

2011-01-01

This study investigated the inhibitory effect of vitamin D-binding protein-derived macrophage-activating factor (GcMAF) on carcinogenesis and tumor growth, using a 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced hamster cheek pouch carcinogenesis model, as well as the cytocidal effect of activated macrophages against HCPC-1, a cell line established from DMBA-induced cheek pouch carcinoma. DMBA application induced squamous cell carcinoma in all 15 hamsters of the control group at approximately 10 weeks, and all 15 hamsters died of tumor burden within 20 weeks. By contrast, 2 out of the 14 hamsters with GcMAF administration did not develop tumors and the remaining 12 hamsters showed a significant delay of tumor development for approximately 3.5 weeks. The growth of tumors formed was significantly suppressed and none of the hamsters died within the 20 weeks during which they were observed. When GcMAF administration was stopped at the 13th week of the experiment in 4 out of the 14 hamsters in the GcMAF-treated group, tumor growth was promoted, but none of the mice died within the 20-week period. On the other hand, when GcMAF administration was commenced after the 13th week in 5 out of the 15 hamsters in the control group, tumor growth was slightly suppressed and all 15 hamsters died of tumor burden. However, the mean survival time was significantly extended. GcMAF treatment activated peritoneal macrophages in vitro and in vivo, and these activated macrophages exhibited a marked cytocidal effect on HCPC-1 cells. Furthermore, the cytocidal effect of activated macrophages was enhanced by the addition of tumor-bearing hamster serum. These findings indicated that GcMAF possesses an inhibitory effect on tumor development and growth in a DMBA-induced hamster cheek pouch carcinogenesis model. PMID:22848250

Hematologic Assessment in Pet Rats, Mice, Hamsters, and Gerbils: Blood Sample Collection and Blood Cell Identification.

PubMed

Lindstrom, Nicole M; Moore, David M; Zimmerman, Kurt; Smith, Stephen A

2015-09-01

Hamsters, gerbils, rats, and mice are presented to veterinary clinics and hospitals for prophylactic care and treatment of clinical signs of disease. Physical examination, history, and husbandry practice information can be supplemented greatly by assessment of hematologic parameters. As a resource for veterinarians and their technicians, this article describes the methods for collection of blood, identification of blood cells, and interpretation of the hemogram in mice, rats, gerbils, and hamsters. Copyright © 2015 Elsevier Inc. All rights reserved.

Large-Scale Transient Transfection of Chinese Hamster Ovary Cells in Suspension.

PubMed

Rajendra, Yashas; Balasubramanian, Sowmya; Hacker, David L

2017-01-01

We describe a one-liter transfection of suspension-adapted Chinese hamster ovary (CHO-DG44) cells using polyethyleneimine (PEI) for DNA delivery. The method involves transfection at a high cell density (5 × 10 6 cells/mL) by direct addition of plasmid DNA (pDNA) and PEI to the culture and subsequent incubation at 31 °C with agitation by orbital shaking. We also describe an alternative method in which 90% of the pDNA is replaced by nonspecific (filler) DNA, and the production phase is performed at 31 °C in the presence of 0.25% N, N-dimethylacetamide (DMA).

Chromosomal mutations and chromosome loss measured in a new human-hamster hybrid cell line, ALC: studies with colcemid, ultraviolet irradiation, and 137Cs gamma-rays

NASA Technical Reports Server (NTRS)

Kraemer, S. M.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

1997-01-01

Small mutations, megabase deletions, and aneuploidy are involved in carcinogenesis and genetic defects, so it is important to be able to quantify these mutations and understand mechanisms of their creation. We have previously quantified a spectrum of mutations, including megabase deletions, in human chromosome 11, the sole human chromosome in a hamster-human hybrid cell line AL. S1- mutants have lost expression of a human cell surface antigen, S1, which is encoded by the M1C1 gene at 11p13 so that mutants can be detected via a complement-mediated cytotoxicity assay in which S1+ cells are killed and S1- cells survive. But loss of genes located on the tip of the short arm of 11 (11p15.5) is lethal to the AL hybrid, so that mutants that have lost the entire chromosome 11 die and escape detection. To circumvent this, we fused AL with Chinese hamster ovary (CHO) cells to produce a new hybrid, ALC, in which the requirement for maintaining 11p15.5 is relieved, allowing us to detect mutations events involving loss of 11p15.5. We evaluated the usefulness of this hybrid by conducting mutagenesis studies with colcemid, 137Cs gamma-radiation and UV 254 nm light. Colcemid induced 1000 more S1- mutants per unit dose in ALC than in AL; the increase for UV 254 nm light was only two-fold; and the increase for 137Cs gamma-rays was 12-fold. The increase in S1- mutant fraction in ALC cells treated with colcemid and 137Cs gamma-rays were largely due to chromosome loss and 11p deletions often containing a breakpoint within the centromeric region.

The induction by X-rays of chromosome aberrations in male guinea-pigs, golden hamsters and rabbits. II. Properties of translocations induced in post-meiotic stages.

PubMed

Cox, B D; Lyon, M F

1975-07-01

Translocations induced by X-rays in post-meiotic germ cells of male guinea-pigs, golden hamsters and rabbits were studied cytologically in the F1 sons of the irradiated males. The percentage of spermatocytes displaying multivalent configurations varied with the translocation, but the average percentage appeared to depend on the species: fewer quadrivalents were observed in hamster than in guinea-pig heterozygotes and most were recorded for rabbit heterozygotes. Chain quadrivalents were more abundant than ring quadrivalents at meiosis for the guinea-pig and hamster, in contrast to the mouse. Too few translocation heterozygotes were examined to determine which meiotic configuration was the more prevalent in the rabbit. In all three species, as in the mouse, translocations were found which caused male sterility, due to partial or complete failure of spermatogenesis, although most translocations caused semi-sterility. For these semi-sterile males both the frequency and time of embryonic death in the progeny appeared to be the same as in the mouse. It is concluded that similar types of chromosome aberrations are induced by X-rays in post-meiotic germ cells of male guinea-pigs, rabbits, golden hamsters and mice.

Metabolic design of macroscopic bioreaction models: application to Chinese hamster ovary cells.

PubMed

Provost, A; Bastin, G; Agathos, S N; Schneider, Y-J

2006-12-01

The aim of this paper is to present a systematic methodology to design macroscopic bioreaction models for cell cultures based upon metabolic networks. The cell culture is seen as a succession of phases. During each phase, a metabolic network represents the set of reactions occurring in the cell. Then, through the use of the elementary flux modes, these metabolic networks are used to derive macroscopic bioreactions linking the extracellular substrates and products. On this basis, as many separate models are obtained as there are phases. Then, a complete model is obtained by smoothly switching from model to model. This is illustrated with batch cultures of Chinese hamster ovary cells.

Senile amyloidosis and neuron binding antibody in the aging Syrian hamster

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blumenthal, H.T.; Musacchia, X.J.

1985-05-01

The effects of age, sex, and irradiation on the genesis of amyloidosis, neuron-binding antibody (NBA), and the concomitant appearance of these two phenomena were studied in a colony of Syrian hamsters. In nonirradiated controls amyloidosis increased in prevalence with age after 12 months, and prevalence was higher in females than in males. Irradiation had the effect of advancing the appearance of amyloidosis to the 7-12 months group but did not intensify the amyloidotic process. IgG binding to the nucleus or cytoplasm of neurons was rare, and, despite the fact that IgM and IgA binding to these structures was present inmore » about one-third of the animals, there was neither an aging nor an irradiation effect. The only statistically significant findings with respect to the concomitant occurrence of amyloid and NBA were negative correlations between nuclear IgM and IgA binding and amyloidosis. Of the various species thus far studied, the hamster is the first in which there has been no aging effect in respect to NBA.« less

Etiology of Tetracycline-Associated Pseudomembranous Colitis in Hamsters

PubMed Central

Toshniwal, Renu; Fekety, Robert; Silva, Joseph

1979-01-01

Tetracyclines were implicated in the 1950s in induction of protracted diarrhea and pseudomembranous colitis. Because the pathogenetic mechanism of these illnesses has been questioned recently, we studied tetracycline in hamster models of antibiotic-associated colitis. Orogastric administration of tetracycline caused diarrhea and death, with evidence of hemorrhagic typhlitis. Filtrates of cecal contents were toxic when inoculated into normal hamsters and cell culture monolayers, and toxicity was neutralized with Clostridium sordellii antitoxin. Tetracycline-resistant C. difficile was cultured from stools of these hamsters, but Staphylococcus aureus was not isolated. The value of tetracycline for treatment or prevention of clindamycin-induced colitis in hamsters was also studied, and it was found that daily orogastric administration of tetracycline was poorly protective against clindamycin-induced colitis. PMID:485127

Model-based analysis of N-glycosylation in Chinese hamster ovary cells

PubMed Central

Krambeck, Frederick J.; Bennun, Sandra V.; Betenbaugh, Michael J.

2017-01-01

The Chinese hamster ovary (CHO) cell is the gold standard for manufacturing of glycosylated recombinant proteins for production of biotherapeutics. The similarity of its glycosylation patterns to the human versions enable the products of this cell line favorable pharmacokinetic properties and lower likelihood of causing immunogenic responses. Because glycan structures are the product of the concerted action of intracellular enzymes, it is difficult to predict a priori how the effects of genetic manipulations alter glycan structures of cells and therapeutic properties. For that reason, quantitative models able to predict glycosylation have emerged as promising tools to deal with the complexity of glycosylation processing. For example, an earlier version of the same model used in this study was used by others to successfully predict changes in enzyme activities that could produce a desired change in glycan structure. In this study we utilize an updated version of this model to provide a comprehensive analysis of N-glycosylation in ten Chinese hamster ovary (CHO) cell lines that include a wild type parent and nine mutants of CHO, through interpretation of previously published mass spectrometry data. The updated N-glycosylation mathematical model contains up to 50,605 glycan structures. Adjusting the enzyme activities in this model to match N-glycan mass spectra produces detailed predictions of the glycosylation process, enzyme activity profiles and complete glycosylation profiles of each of the cell lines. These profiles are consistent with biochemical and genetic data reported previously. The model-based results also predict glycosylation features of the cell lines not previously published, indicating more complex changes in glycosylation enzyme activities than just those resulting directly from gene mutations. The model predicts that the CHO cell lines possess regulatory mechanisms that allow them to adjust glycosylation enzyme activities to mitigate side effects of

The effects of radiation on antitumor efficacy of an oncolytic adenovirus vector in the Syrian hamster model

PubMed Central

Young, Brittany A.; Spencer, Jacqueline F.; Ying, Baoling; Toth, Karoly; Wold, William S. M.

2013-01-01

We report that radiation enhances the antitumor efficacy of the oncolytic adenovirus vector VRX-007 in Syrian hamster tumors. We used tumor-specific irradiation of subcutaneous tumors and compared treatment options of radiation alone or combined with VRX-007 and cyclophosphamide (CP). Radiation therapy further augmented the VRX-007-mediated inhibition of tumor growth, in both CP-treated and non-CP-treated hamsters, even though radiation did not lead to increased viral replication in tumors when compared to those treated with VRX-007 alone. Moreover, tumor growth inhibition was similar in tumors irradiated either one week before or after injection with VRX-007, which suggests that radiation exerts its antitumor effect independently from vector therapy. Thus, our results demonstrate that these two therapies do not have to be provided simultaneously to enhance their combined effectiveness against subcutaneous hamster tumors. PMID:23928730

The effects of radiation on antitumor efficacy of an oncolytic adenovirus vector in the Syrian hamster model.

PubMed

Young, B A; Spencer, J F; Ying, B; Toth, K; Wold, W S M

2013-09-01

We report that radiation enhances the antitumor efficacy of the oncolytic adenovirus vector VRX-007 in Syrian hamster tumors. We used tumor-specific irradiation of subcutaneous tumors and compared treatment options of radiation alone or combined with VRX-007 and cyclophosphamide (CP). Radiation therapy further augmented the VRX-007-mediated inhibition of tumor growth, in both CP-treated and non-CP-treated hamsters, even though radiation did not lead to increased viral replication in tumors when compared with those treated with VRX-007 alone. Moreover, tumor growth inhibition was similar in tumors irradiated either 1 week before or after injection with VRX-007, which suggests that radiation exerts its antitumor effect independently from vector therapy. Thus, our results demonstrate that these two therapies do not have to be provided simultaneously to enhance their combined effectiveness against subcutaneous hamster tumors.

Induction of Thioguanine- and Ouabain-Resistant Mutants and Single-Strand Breaks in the DNA of Chinese Hamster Ovary Cells by 3H-Thymidine

PubMed Central

Cleaver, James E.

1977-01-01

Cultured Chinese hamster cells were labeled with 6-3H-thymidine or 5-methyl-3H-thymidine and allowed to accumulate damage from 3H decays for various periods of time while frozen. The frequencies of cells resistant to 6-thioguanine or ouabain and the amount of DNA damage (i.e., number of single-strand breaks) were determined and compared with the mutation frequencies resulting from X and ultraviolet light irradiation. Whereas 3H decays and X rays made only 6-thioguanine-resistant mutants, ultraviolet light made both 6-thioguanine- and ouabain-resistant mutants. 3H decays originating at the 6 position were two to three times as effective as decays at the 5-methyl position in making drug-resistant mutants, but decays at both sites were equally effective in making single-strand breaks. Mutants and strand breaks produced by beta irradiation of the nucleus probably are the same irrespective of the site of the decay in thymine; these results indicate that the local transmutation effects of 3H decay produce more mutations when they occur at the 6 position than at the 5-methyl position. PMID:914028

Effect of ambient temperature on the proliferation of brown adipocyte progenitors and endothelial cells during postnatal BAT development in Syrian hamsters.

PubMed

Nagaya, Kazuki; Okamatsu-Ogura, Yuko; Nio-Kobayashi, Junko; Nakagiri, Shohei; Tsubota, Ayumi; Kimura, Kazuhiro

2018-04-02

In Syrian hamsters, brown adipose tissue (BAT) develops postnatally through the proliferation and differentiation of brown adipocyte progenitors. In the study reported here, we investigated how ambient temperature influenced BAT formation in neonatal hamsters. In both hamsters raised at 23 or 30 °C, the interscapular fat changed from white to brown coloration in an age-dependent manner and acquired the typical morphological features of BAT by day 16. However, the expression of uncoupling protein 1, a brown adipocyte marker, and of vascular endothelial growth factor α were lower in the group raised at 30 °C than in that raised at 23 °C. Immunofluorescent staining revealed that the proportion of Ki67-expressing progenitors and endothelial cells was lower in the 30 °C group than in the 23 °C group. These results indicate that warm ambient temperature suppresses the proliferation of brown adipocyte progenitors and endothelial cells and negatively affects the postnatal development of BAT in Syrian hamsters.

CELLULAR TOXICITY IN CHINESE HAMSTER OVARY CELL CULTURES. 1. ANALYSIS OF CYTOTOXICITY ENDPOINTS FOR TWENTY-NINE PRIORITY POLLUTANTS

EPA Science Inventory

Chinese hamster ovary cells were exposed to 29 toxic chemical substances which were representative of several classes of compounds listed by the Natural Resources Defense Council Consent Decree as priority toxic pollutants. After cell cultures were exposed to the test substance, ...

Histological study of cell migration in the dermis of hamsters after immunisation with two different vaccines against visceral leishmaniasis.

PubMed

Moreira, Nádia das Dores; Giunchetti, Rodolfo Cordeiro; Carneiro, Cláudia Martins; Vitoriano-Souza, Juliana; Roatt, Bruno Mendes; Malaquias, Luiz Cosme Cotta; Corrêa-Oliveira, Rodrigo; Reis, Alexandre Barbosa

2009-04-15

Vaccine candidates, including live and/or killed parasites, Leishmania-purified fractions, defined recombinant antigens and antigen-encoding DNA-plasmids have been proposed to use as vaccine anti-Leishmania. More recently, the hamsters have been used to pre-selection of antigens candidate to apply in further experiments using canine model. In this report we evaluated the kinetics of cell migration in dermal inflammatory infiltrate, circulating leukocytes and the presence of nitric oxide (NO)/induced nitric oxide synthase during the early (1-24h) and late (48-168h) periods following inoculation of hamsters with antigenic components of anti-canine visceral leishmaniasis vaccines Leishmune and Leishmania braziliensis antigen (LB) with and without saponin (Sap) adjuvant. Our results show that LB caused an early reduction of lymphocytes in the dermis while Sap and LBSap triggered a late recruitment, suggesting the role of the adjuvant in the traffic of antigen-presenting cells and the induction of lymphocyte migration. In that manner our results suggest that the kinetics of cell migration on hamster model may be of value in the selection of vaccine antigens prior the tests in dogs particularly in respect of the toxicity of the preparations.

Ascorbate, added after irradiation, reduces the mutant yield and alters the spectrum of CD59- mutations in A(L) cells irradiated with high LET carbon ions

NASA Technical Reports Server (NTRS)

Ueno, Akiko; Vannais, Diane; Lenarczyk, Marek; Waldren, Charles A.; Chatterjee, A. (Principal Investigator)

2002-01-01

It has been reported that X-ray induced HPRT- mutation in cultured human cells is prevented by ascorbate added after irradiation. Mutation extinction is attributed to neutralization by ascorbate, of radiation-induced long-lived radicals (LLR) with half-lives of several hours. We here show that post-irradiation treatment with ascorbate (5 mM added 30 min after radiation) reduces, but does not eliminate, the induction of CD59- mutants in human-hamster hybrid A(L) cells exposed to high-LET carbon ions (LET of 100 KeV/microm). RibCys, [2(R,S)-D-ribo-1',2',3',4'-Tetrahydroxybutyl]-thiazolidene-4(R)-ca riboxylic acid] (4 mM) gave a similar but lesser effect. The lethality of the carbon ions was not altered by these chemicals. Preliminary data are presented that ascorbate also alters the spectrum of CD59- mutations induced by the carbon beam, mainly by reducing the incidence of small mutations and mutants displaying transmissible genomic instability (TGI), while large mutations are unaffected. Our results suggest that LLR are important in initiating TGI.

Mechanisms driving the lactate switch in Chinese hamster ovary cells.

PubMed

Hartley, Fiona; Walker, Tracy; Chung, Vicky; Morten, Karl

2018-03-31

The metabolism of Chinese Hamster Ovary (CHO) cells in a production environment has been extensively investigated. However, a key metabolic transition, the switch from lactate production to lactate consumption, remains enigmatic. Though commonly observed in CHO cultures, the mechanism(s) by which this metabolic shift is triggered is unknown. Despite this, efforts to control the switch have emerged due to the association of lactate consumption with improved cell growth and productivity. This review aims to consolidate current theories surrounding the lactate switch. The influence of pH, NAD + /NADH, pyruvate availability and mitochondrial function on lactate consumption are explored. A hypothesis based on the cellular redox state is put forward to explain the onset of lactate consumption. Various techniques implemented to control the lactate switch, including manipulation of the culture environment, genetic engineering, and cell line selection are also discussed. © 2018 Wiley Periodicals, Inc.

Targeted delivery of antigen to hamster nasal lymphoid tissue with M-cell-directed lectins.

PubMed Central

Giannasca, P J; Boden, J A; Monath, T P

1997-01-01

The nasal cavity of a rodent is lined by an epithelium organized into distinct regional domains responsible for specific physiological functions. Aggregates of nasal lymphoid tissue (NALT) located at the base of the nasal cavity are believed to be sites of induction of mucosal immune responses to airborne antigens. The epithelium overlying NALT contains M cells which are specialized for the transcytosis of immunogens, as demonstrated in other mucosal tissues. We hypothesized that NALT M cells are characterized by distinct glycoconjugate receptors which influence antigen uptake and immune responses to transcytosed antigens. To identify glycoconjugates that may distinguish NALT M cells from other cells of the respiratory epithelium (RE), we performed lectin histochemistry on sections of the hamster nasal cavity with a panel of lectins. Many classes of glycoconjugates were found on epithelial cells in this region. While most lectins bound to sites on both the RE and M cells, probes capable of recognizing alpha-linked galactose were found to label the follicle-associated epithelium (FAE) almost exclusively. By morphological criteria, the FAE contains >90% M cells. To determine if apical glycoconjugates on M cells were accessible from the nasal cavity, an M-cell-selective lectin and a control lectin in parallel were administered intranasally to hamsters. The M-cell-selective lectin was found to specifically target the FAE, while the control lectin did not. Lectin bound to M cells in vivo was efficiently endocytosed, consistent with the role of M cells in antigen transport. Intranasal immunization with lectin-test antigen conjugates without adjuvant stimulated induction of specific serum immunoglobulin G, whereas antigen alone or admixed with lectin did not. The selective recognition of NALT M cells by a lectin in vivo provides a model for microbial adhesin-host cell receptor interactions on M cells and the targeted delivery of immunogens to NALT following intranasal

Caffeine sensitization of cultured mammalian cells and human lymphocytes irradiated with gamma rays and fast neutrons: a study of relative biological effectiveness in relation to cellular repair

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hannan, M.A.; Gibson, D.P.

1985-10-01

The sensitizing effects of caffeine were studied in baby hamster kidney (BHK-21) cells and human lymphocytes following irradiation with gamma rays and fast neutrons. Caffeine sensitization occurred only when log-phase BHK cells and mitogen-stimulated lymphocytes were exposed to the two radiations. Noncycling (confluent) cells of BHK resulted in a shouldered survival curve following gamma irradiation while a biphasic curve was obtained with the log-phase cells. Survival in the case of lymphocytes was estimated by measurement of (TH)thymidine uptake. The relative biological effectiveness (RBE) of fast neutrons was found to be greater at survival levels corresponding to the resistant portions ofmore » the survival curves (shoulder or resistant tail). In both cell types, no reduction in RBE was observed when caffeine was present, because caffeine affected both gamma and neutron survival by the same proportion.« less

Photoperiod-dependent modulation of anti-Müllerian hormone in female Siberian hamsters, Phodopus sungorus.

PubMed

Kabithe, Esther W; Place, Ned J

2008-03-01

Fertility and fecundity decline with advancing age in female mammals, but reproductive aging was decelerated in Siberian hamsters (Phodopus sungorus) raised in a short-day (SD) photoperiod. Litter success was significantly improved in older hamsters when reared in SD and the number of primordial follicles was twice that of females held in long days (LD). Because anti-Müllerian hormone (AMH) appears to inhibit the recruitment of primordial follicles in mice, we sought to determine whether the expression patterns of AMH differ in the ovaries and serum of hamsters raised in SD versus LD. Ovaries of SD female hamsters are characterized by a paucity of follicular development beyond the secondary stage and are endowed with an abundance of large eosinophilic cells, which may derive from granulosa cells of oocyte-depleted follicles. In ovaries from 10-week-old SD hamsters, we found that the so-called 'hypertrophied granulosa cells' were immunoreactive for AMH, as were granulosa cells within healthy-appearing primary and secondary follicles. Conversely, ovaries from age-matched LD animals lack the highly eosinophilic cells present in SD ovaries. Therefore, AMH staining in LD was limited to primary and secondary follicles that are comparable in number to those found in SD ovaries. The substantially greater AMH expression in SD ovaries probably reflects the abundance of hypertrophied granulosa cells in SD ovaries and their relative absence in LD ovaries. The modulation of ovarian AMH by day length is a strong mechanistic candidate for the preservation of primordial follicles in female hamsters raised in a SD photoperiod.

Characterisation of monoclonal antibodies specific for hamster leukocyte differentiation molecules.

PubMed

Rees, Jennifer; Haig, David; Mack, Victoria; Davis, William C

2017-01-01

Flow cytometry was used to identify mAbs that recognize conserved epitopes on hamster leukocyte differentiation molecules (hLDM) and also to characterize mAbs developed against hLDM. Initial screening of mAbs developed against LDMs in other species yielded mAbs specific for the major histocompatibility (MHC) II molecule, CD4 and CD18. Screening of sets of mAbs developed against hLDM yielded 22 new mAbs, including additional mAbs to MHC II molecules and mAbs that recognize LDMs expressed on all leukocytes, granulocytes, all lymphocytes, all T cells, a subset of T cells, or on all B cells. Based on comparison of the pattern of expression of LDMs expressed on all hamster leukocytes with the patterns of expression of known LDMs in other species, as detected by flow cytometry (FC), four mAbs are predicted to recognize CD11a, CD44, and CD45. Cross comparison of mAbs specific for a subset of hamster T cells with a cross reactive mAb known to recognize CD4 in mice and one recognising CD8 revealed they recognize CD4. The characterization of these mAbs expands opportunities to use hamsters as an additional model species to investigate the mechanisms of immunopathogenesis of infectious diseases. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Single Unit Recordings of Cells Responsive to Visual, Somatic, Acoustic, and Noxious Stimuli in the Superior Colliculus of the Golden Hamster.

DTIC Science & Technology

1978-08-01

Acoustic, and Noxious Stimuli Thesis in the Superior Colliculus of the Golden 6. PERFORMING OG. REPORT NUMBER Hamster -. _ // 7. AUTHOR( a ) S. CONTRACT...OR GRANT NUMBER(s) James P. Dixon I - "JV 9. PERF 7 MING ORGANIZATION NAME A D10. PROGRAM ELEMENT, PROJECT, TASK AFIT Student at: Virginia...studied in the superior colliculus of the golden hamster. A laminar organiza- tion was observed with cells in the superficial layers responding exclusively

Augmenting Chinese hamster genome assembly by identifying regions of high confidence.

PubMed

Vishwanathan, Nandita; Bandyopadhyay, Arpan A; Fu, Hsu-Yuan; Sharma, Mohit; Johnson, Kathryn C; Mudge, Joann; Ramaraj, Thiruvarangan; Onsongo, Getiria; Silverstein, Kevin A T; Jacob, Nitya M; Le, Huong; Karypis, George; Hu, Wei-Shou

2016-09-01

Chinese hamster Ovary (CHO) cell lines are the dominant industrial workhorses for therapeutic recombinant protein production. The availability of genome sequence of Chinese hamster and CHO cells will spur further genome and RNA sequencing of producing cell lines. However, the mammalian genomes assembled using shot-gun sequencing data still contain regions of uncertain quality due to assembly errors. Identifying high confidence regions in the assembled genome will facilitate its use for cell engineering and genome engineering. We assembled two independent drafts of Chinese hamster genome by de novo assembly from shotgun sequencing reads and by re-scaffolding and gap-filling the draft genome from NCBI for improved scaffold lengths and gap fractions. We then used the two independent assemblies to identify high confidence regions using two different approaches. First, the two independent assemblies were compared at the sequence level to identify their consensus regions as "high confidence regions" which accounts for at least 78 % of the assembled genome. Further, a genome wide comparison of the Chinese hamster scaffolds with mouse chromosomes revealed scaffolds with large blocks of collinearity, which were also compiled as high-quality scaffolds. Genome scale collinearity was complemented with EST based synteny which also revealed conserved gene order compared to mouse. As cell line sequencing becomes more commonly practiced, the approaches reported here are useful for assessing the quality of assembly and potentially facilitate the engineering of cell lines. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Morphometric and histological analysis of the lungs of Syrian golden hamsters.

PubMed Central

Kennedy, A R; Desrosiers, A; Terzaghi, M; Little, J B

1978-01-01

Hamster lung morphometry and histology have been studied in an attempt to determine differences between hamster and human lungs which may have relevance for lung carcinogenesis studies. Morphometric measurements were made on fresh lungs, lung casts, and histological sections. Cell type and frequency measurements were determined from frozen, paraffin, 1 micron plastic (glycol methacrylate) and electron microscopic sections. A standard terminology for hamster lung histology is established, and differences between hamster and human lung morphometry and histology are discussed. Images Fig. 2 Fig. 3 Fig. 4 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 18 Fig. 19 Fig. 20 Fig. 21 Fig. 22 PMID:640957

Stable Expression of the Motor Protein Prestin in Chinese Hamster Ovary Cells

NASA Astrophysics Data System (ADS)

Iida, Koji; Konno, Kazuaki; Oshima, Takeshi; Tsumoto, Kouhei; Ikeda, Katsuhisa; Kumagai, Izumi; Kobayashi, Toshimitsu; Wada, Hiroshi

Mammalian hearing sensitivity relies on a mechanical amplification mechanism involving the outer hair cells (OHCs), which rapidly alter their longitudinal length in response to changes in their membrane potential. The molecular basis of this mechanism is thought to be a motor protein embedded in the lateral membrane of the OHCs. Recently, this motor protein was identified and termed prestin. Since then, prestin has been researched intensively to elucidate the behavior of the OHCs. However, little progress in the study of prestin at the molecular level has been made because no method of obtaining an adequate amount of prestin has been established. In this study, therefore, an attempt was made to construct a stable expression system of prestin using Chinese hamster ovary (CHO) cells. The expression of prestin in the transfected CHO cells and the activity of prestin on CHO cells were confirmed by immunofluorescence and whole-cell patch-clamp measurements, respectively.

Alpha 1-protease inhibitor moderates human neutrophil elastase-induced emphysema and secretory cell metaplasia in hamsters.

PubMed

Stone, P J; Lucey, E C; Virca, G D; Christensen, T G; Breuer, R; Snider, G L

1990-06-01

A study was undertaken to determine whether emphysema and airway secretory cell metaplasia, induced in hamsters by intratracheal treatment with human neutrophil elastase (HNE), could be moderated by pretreatment with human alpha 1-protease inhibitor (API). API (4.9 mg) was given intratracheally to hamsters 1 h before 0.3 mg HNE. Eight weeks later, lung volumes and pressure-volume relationships were measured in the anaesthetized animals. Mean linear intercepts and secretory cell indices were measured in lung sections. API given 1 h before HNE moderated the development of bronchial secretory cell metaplasia. The severity of emphysema was reduced by 75%. Clearance studies indicated that 80% of the functional activity of instilled API could be lavaged from the lungs after 1 h, indicating a 4 h half-life in the lavageable compartment of the lungs. We calculate that for 50% protection from emphysema the molar ratio of lavageable API to HNE at the time of HNE instillation was 4.8 as compared with 0.78 for 50% inhibition of elastolytic activity in vitro, indicating that API is only 16% as efficient in vivo as compared with its in vitro HNE inhibitory effectiveness. Nevertheless, we conclude that human API given intratracheally is efficacious against HNE-induced emphysema and secretory cell metaplasia.

DNA Double-strand Breaks Induced byFractionated Neutron Beam Irradiation for Boron Neutron Capture Therapy.

PubMed

Kinashi, Yuko; Yokomizo, Natsuya; Takahashi, Sentaro

2017-04-01

To use the 53BP1 foci assay to detect DNA double-strand breaks induced by fractionated neutron beam irradiation of normal cells. The Kyoto University Research Reactor heavy-water facility and gamma-ray irradiation system were used as experimental radiation sources. After fixation of Chinese Hamster Ovary cells with 3.6% formalin, immunofluorescence staining was performed. Number and size of foci were analyzed using ImageJ software. Fractionated neutron irradiation induced 25% fewer 53BP1 foci than single irradiation at the same dose. By contrast, gamma irradiation induced 30% fewer 53BP1 foci than single irradiation at the same dose. Fractionated neutron irradiation induced larger foci than gamma irradiation, raising the possibility that persistent unrepaired DNA damage was amplified due to the high linear energy transfer component in the neutron beam. Unrepaired cluster DNA damage was more prevalent after fractionated neutron irradiation than after gamma irradiation. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Mechanisms underlying radiosensitivity : iIvestigations in xrs-5, an X-ray sensitive hamster cell line

NASA Astrophysics Data System (ADS)

Johnston, Peter James

The damage caused to cells by ionising radiation is believed to center on damage to the DNA. In particular, the induction of DNA double strand breaks (DSB) have been implicated in biological end-points such as cell killing and the formation of chromosomal aberrations. The xrs-5 cell line is a mutant Chinese hamster ovary fibroblast (CHO-K1) mutant which exhibits sensitivity to ionising radiation and a number of other DNA damaging agents. This mutation, postulated to involve the hamster homologue of the human XRCC5 gene, is believed to be involved in the repair of the DSB. In addition, there are constitutive differences between the wild type and xrs cells involving the structure and function of the nucleus and higher order chromatin structures. The aims of this thesis were to study further the xrs-5 cell line and its response to DNA damage and to investigate the possible link between chromatin structure and DSB repair. By the examination of the response of xrs-5 cells to a number of DNA damaging agents and potential modulators of this response using the cytokinesis block micronucleus assay [Fenech and Morley, 1985] a possible cell cycle defect was identified in addition to elevated levels of chromosomal damage. Xrs-5 cells appeared to be partially defective in the cell cycle checkpoints involving the passage from G2 phase to mitosis. By the use of a modified neutral filter elution procedure variations in the repair of DSB were observed between xrs-5 and CHO. Conventional neutral filter elution requires harsh lysis conditions to remove higher order chromatin structures which interfere with the elution of DNA containing DSB. By lysing cells with non-ionic detergent in the presence of 2 M NaC1, histone depleted structures which retain the higher order nuclear matrix organisation, including chromatin loops, can be produced. Elution from these structures will only occur if two or more DSB lie within a single looped domain delineated by points of attachment to the nuclear

The antioxidant effect of the Malaysian Gelam honey on pancreatic hamster cells cultured under hyperglycemic conditions.

PubMed

Batumalaie, Kalaivani; Qvist, Rajes; Yusof, Kamaruddin Mohd; Ismail, Ikram Shah; Sekaran, Shamala Devi

2014-05-01

Type 2 diabetes consists of progressive hyperglycemia, insulin resistance, and pancreatic β-cell failure which could result from glucose toxicity, inflammatory cytokines, and oxidative stress. In the present study, we investigate the effect of pretreatment with Gelam honey (Melaleuca spp.) and the individual flavonoid components chrysin, luteolin, and quercetin, on the production of reactive oxygen species (ROS), cell viability, lipid peroxidation, and insulin content in hamster pancreatic cells (HIT-T15 cells), cultured under normal and hyperglycemic conditions. Phenolic extracts from a local Malaysian species of Gelam honey (Melaleuca spp.) were prepared using the standard extraction methods. HIT-T15 cells were cultured in 5 % CO2 and then preincubated with Gelam honey extracts (20, 40, 60, and 80 μg/ml) as well as some of its flavonoid components chrysin, luteolin, and quercetin (20, 40, 60, and 80 μM), prior to stimulation by 20 and 50 mM of glucose. The antioxidative effects were measured in these cultured cells at different concentrations and time point by DCFH-DA assay. Pretreatment of cells with Gelam honey extract or the flavonoid components prior to culturing in 20 or 50 mM glucose showed a significant decrease in the production of ROS, glucose-induced lipid peroxidation, and a significant increase in insulin content and the viability of cells cultured under hyperglycemic condition. Our results show the in vitro antioxidative property of the Gelam honey and the flavonoids on the β-cells from hamsters and its cytoprotective effect against hyperglycemia.

Modified multiple drug resistance phenotype of Chinese hamster ovary cells selected with X-rays and vincristine versus X-rays only.

PubMed Central

McClean, S.; Hill, B. T.

1994-01-01

Exposure of Chinese hamster ovary (CHO) cells to fractionated X-irradiation [ten fractions of 9 Gray (Gy)] resulted in the expression of a multiple drug resistance phenotype which was distinct from that of drug-selected cells in two features: (i) resistance to vinca alkaloids and epipodophyllotoxins but sensitivity to anthracyclines was retained; (ii) overexpression of P-glycoprotein (Pgp) but regulated by post-translational stability rather than by any elevation in Pgp mRNA (Hill et al., 1990). It was also reported that when these cells (designated DXR-10) were subsequently exposed to another ten fractions of 9 Gy (20 x 9 Gy in total), no further increases in drug resistance or in the extent of Pgp expression were observed. To examine this apparent plateauing of the drug resistance phenotype following X-ray pretreatment, DXR-10 cells were instead treated with ten pulsed vincristine exposures. The resultant cell line, designated DXR-10/VCR-10, proved to be more resistant to vincristine, implying that the effect of further drug selection was additive to that of X-ray pretreatment. In addition, these cells showed resistance to doxorubicin and increased Pgp expression which was matched by a concomitant elevation in Pgp mRNA. These findings appear to confirm that Pgp expression is differentially regulated in tumour cells showing drug resistance after drug as opposed to X-ray selection. Images Figure 2 Figure 3 Figure 5 PMID:7908216

Sequencing, Annotation and Analysis of the Syrian Hamster (Mesocricetus auratus) Transcriptome

PubMed Central

Tchitchek, Nicolas; Safronetz, David; Rasmussen, Angela L.; Martens, Craig; Virtaneva, Kimmo; Porcella, Stephen F.; Feldmann, Heinz

2014-01-01

Background The Syrian hamster (golden hamster, Mesocricetus auratus) is gaining importance as a new experimental animal model for multiple pathogens, including emerging zoonotic diseases such as Ebola. Nevertheless there are currently no publicly available transcriptome reference sequences or genome for this species. Results A cDNA library derived from mRNA and snRNA isolated and pooled from the brains, lungs, spleens, kidneys, livers, and hearts of three adult female Syrian hamsters was sequenced. Sequence reads were assembled into 62,482 contigs and 111,796 reads remained unassembled (singletons). This combined contig/singleton dataset, designated as the Syrian hamster transcriptome, represents a total of 60,117,204 nucleotides. Our Mesocricetus auratus Syrian hamster transcriptome mapped to 11,648 mouse transcripts representing 9,562 distinct genes, and mapped to a similar number of transcripts and genes in the rat. We identified 214 quasi-complete transcripts based on mouse annotations. Canonical pathways involved in a broad spectrum of fundamental biological processes were significantly represented in the library. The Syrian hamster transcriptome was aligned to the current release of the Chinese hamster ovary (CHO) cell transcriptome and genome to improve the genomic annotation of this species. Finally, our Syrian hamster transcriptome was aligned against 14 other rodents, primate and laurasiatheria species to gain insights about the genetic relatedness and placement of this species. Conclusions This Syrian hamster transcriptome dataset significantly improves our knowledge of the Syrian hamster's transcriptome, especially towards its future use in infectious disease research. Moreover, this library is an important resource for the wider scientific community to help improve genome annotation of the Syrian hamster and other closely related species. Furthermore, these data provide the basis for development of expression microarrays that can be used in functional

Unusual neutral oligosaccharides in mature Sindbis virus glycoproteins are synthesized from truncated precursor oligosaccharides in Chinese hamster ovary cells.

PubMed

Davidson, S K; Hunt, L A

1983-03-01

We have previously demonstrated the presence of unusual small asparaginyl-oligosaccharides [(Man)3GlcNAc2-ASN] in the mature glycoproteins of Sindbis virus released from both wild-type and lectin-resistant Chinese hamster ovary cells, but the mechanism of synthesis of these structures was not determined. Gel filtration and endo-beta-N-acetylglucosaminidase analyses of Pronase-digested glycopeptides from [3H]mannose-labelled Sindbis virus released at different times after infection of a phytohaemagglutinin-resistant line of Chinese hamster ovary cells demonstrated that these small asparaginyl-oligosaccharides were present in similar relative amounts in virus released throughout the virus infection, rather than arising primarily at late times when cytopathic effects were maximal. Similar analyses of pulse-labelled, cell-associated viral glycopeptides suggested that these small oligosaccharides on mature virus glycoprotein resulted from the normal alpha 1,2-mannosidase processing of truncated precursor oligosaccharides (containing five rather than nine mannoses), rather than from aberrant processing or degradation of the full-size precursor oligosaccharides or normal intermediates.

Caffeine-enhanced survival of radiation-sensitive, repair-deficient Chinese hamster cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Utsumi, H.; Elkind, M.M.

1983-11-01

A clone of V79 Chinese hamster cells (V79-AL162/S-10) with unique properties has been isolated after a challenge of parental cells (V79-AL162) with 1 mM ouabain. Compared with parental cells, or with other clones isolated after the ouabain challenge, these cells form smaller colonies, are more sensitive to both x rays and fission-spectrum neutrons, and respond atypically to a postirradiation treatment with caffeine. Their enhanced response to x rays results mainly from a large reduction in the shoulder of their survival curve, probably because in late S phase, the most resistant phase in the cell cycle, the survival curve of thesemore » cells has a reduced shoulder width. Caffeine, and to a lesser extent theophylline, added to the colony-forming medium immediately after exposure appreciably increases the width of the shoulder of these sensitive cells, whereas caffeine has the opposite effect on the response of normal V79 cells. Thus the unique response of the V79-AL162/S-10 cells to a radiation posttreatment with caffeine (increased survival) results from a net increase in their ability to repair damage that is otherwise lethal; caffeine treatment ordinarly prevents normal V79 cells from repairing damage that is only potentially lethal.« less

Effects of proliferation on the decay of thermotolerance in Chinese hamster cells.

PubMed

Armour, E P; Li, G C; Hahn, G M

1985-09-01

Development and decay of thermotolerance were observed in Chinese hamster HA-1 cells. The thermotolerance kinetics of exponentially growing and fed plateau-phase cells were compared. Following a 10-min heat exposure at 45 degrees C, cells in both growth states had similar rates of development of tolerance to a subsequent 45-min exposure at 45 degrees C. This thermotolerant state started to decay between 12 and 24 hr after the initial heat exposure. The decay appeared to initiate slightly sooner in the exponentially growing cells when compared to the fed plateau-phase cells. During the decay phase, the rate of thermotolerance decay was similar in the two growth conditions. In other experiments, cells were induced to divide at a slower rate by chronic growth (3 months) in a low concentration of fetal calf serum. Under these low serum conditions cells became more sensitive to heat and the rate of decay of thermotolerance remained the same for exponentially growing cells. Plateau-phase cells were also more sensitive, but thermotolerance decayed more rapidly in these cells. Although dramatic cell cycle perturbations were seen in the exponentially growing cells, these changes appeared not to be related to thermotolerance kinetics.

Decreased adult neurogenesis in hibernating Syrian hamster.

PubMed

León-Espinosa, Gonzalo; García, Esther; Gómez-Pinedo, Ulises; Hernández, Félix; DeFelipe, Javier; Ávila, Jesús

2016-10-01

Generation of new neurons from adult neural stem cells occurs in the dentate gyrus (DG) of the hippocampus and the lateral walls of the lateral ventricles. In this article, we study the neurogenesis that takes place during the hibernation of the Syrian hamster (Mesocricetus auratus). Using a variety of standard neurogenesis markers and 5-bromo-2-deoxyuridine (BrdU) incorporation, we describe a preferential decrease in the proliferation of newborn neurons in the subventricular zone (SVZ) of the hibernating hamsters (torpor) rather than in the hippocampus. Furthermore, we demonstrate that the proliferative capacity is recovered after 3-4days of torpor when arousal is triggered under natural conditions (i.e., not artificially provoked). In addition, we show that tau3R, a tau isoform with three microtubule-binding domains, is a suitable marker to study neurogenesis both in the SVZ and subgranular zone (SGZ) of the Syrian hamster brain. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Syngeneic syrian hamster tumors feature tumor-infiltrating lymphocytes allowing adoptive cell therapy enhanced by oncolytic adenovirus in a replication permissive setting.

PubMed

Siurala, Mikko; Vähä-Koskela, Markus; Havunen, Riikka; Tähtinen, Siri; Bramante, Simona; Parviainen, Suvi; Mathis, J Michael; Kanerva, Anna; Hemminki, Akseli

2016-05-01

Adoptive transfer of tumor-infiltrating lymphocytes (TIL) has shown promising yet sometimes suboptimal results in clinical trials for advanced cancer, underscoring the need for approaches improving efficacy and safety. Six implantable syngeneic tumor cell lines of the Syrian hamster were used to initiate TIL cultures. TIL generated from tumor fragments cultured in human interleukin-2 (IL-2) for 10 d were adoptively transferred into tumor-bearing hamsters with concomitant intratumoral injections of oncolytic adenovirus (Ad5-D24) for the assessment of antitumor efficacy. Pancreatic cancer (HapT1) and melanoma (RPMI 1846) TIL exhibited potent and tumor-specific cytotoxicity in effector-to-target (E/T) assays. MHC Class I blocking abrogated the cell killing of RPMI 1846 TIL, indicating cytotoxic CD8(+) T-cell activity. When TIL were combined with Ad5-D24 in vitro, HapT1 tumor cell killing was significantly enhanced over single agents. In vivo, the intratumoral administration of HapT1 TIL and Ad5-D24 resulted in improved tumor growth control compared with either treatment alone. Additionally, splenocytes derived from animals treated with the combination of Ad5-D24 and TIL killed autologous tumor cells more efficiently than monotherapy-derived splenocytes, suggesting that systemic antitumor immunity was induced. For the first time, TIL of the Syrian hamster have been cultured, characterized and used therapeutically together with oncolytic adenovirus for enhancing the efficacy of TIL therapy. Our results support human translation of oncolytic adenovirus as an enabling technology for adoptive T-cell therapy of solid tumors.

Syngeneic syrian hamster tumors feature tumor-infiltrating lymphocytes allowing adoptive cell therapy enhanced by oncolytic adenovirus in a replication permissive setting

PubMed Central

Siurala, Mikko; Vähä-Koskela, Markus; Havunen, Riikka; Tähtinen, Siri; Bramante, Simona; Parviainen, Suvi; Mathis, J. Michael; Kanerva, Anna; Hemminki, Akseli

2016-01-01

ABSTRACT Adoptive transfer of tumor-infiltrating lymphocytes (TIL) has shown promising yet sometimes suboptimal results in clinical trials for advanced cancer, underscoring the need for approaches improving efficacy and safety. Six implantable syngeneic tumor cell lines of the Syrian hamster were used to initiate TIL cultures. TIL generated from tumor fragments cultured in human interleukin-2 (IL-2) for 10 d were adoptively transferred into tumor-bearing hamsters with concomitant intratumoral injections of oncolytic adenovirus (Ad5-D24) for the assessment of antitumor efficacy. Pancreatic cancer (HapT1) and melanoma (RPMI 1846) TIL exhibited potent and tumor-specific cytotoxicity in effector-to-target (E/T) assays. MHC Class I blocking abrogated the cell killing of RPMI 1846 TIL, indicating cytotoxic CD8+ T-cell activity. When TIL were combined with Ad5-D24 in vitro, HapT1 tumor cell killing was significantly enhanced over single agents. In vivo, the intratumoral administration of HapT1 TIL and Ad5-D24 resulted in improved tumor growth control compared with either treatment alone. Additionally, splenocytes derived from animals treated with the combination of Ad5-D24 and TIL killed autologous tumor cells more efficiently than monotherapy-derived splenocytes, suggesting that systemic antitumor immunity was induced. For the first time, TIL of the Syrian hamster have been cultured, characterized and used therapeutically together with oncolytic adenovirus for enhancing the efficacy of TIL therapy. Our results support human translation of oncolytic adenovirus as an enabling technology for adoptive T-cell therapy of solid tumors. PMID:27467954

Free radical production by high energy shock waves--comparison with ionizing irradiation.

PubMed

Morgan, T R; Laudone, V P; Heston, W D; Zeitz, L; Fair, W R

1988-01-01

Fricke chemical dosimetry is used as an indirect measure of the free radical production of ionizing irradiation. We adapted the Fricke ferrous sulfate radiation dosimeter to examine the chemical effects of high energy shock waves. Significant free radical production was documented. The reaction was dose dependent, predictably increased by acoustic impedance, but curvilinear. A thousand shocks at 18 kilovolts induced the same free radical oxidation as 1100 rad cobalt-60 gamma ionizing irradiation, increasing to 2900 rad in the presence of an air-fluid zone of acoustic impedance. The biological effect of these free radicals was compared to that of cobalt-60 ionizing irradiation by measuring the affect on Chinese hamster cells by clonogenic assay. While cobalt-60 irradiation produced a marked decrease in clonogenic survivors, little effect was noted with high energy shock waves. This suggested that the chemical effects produced by shock waves were either absent or attenuated in the cells, or were inherently less toxic than those of ionizing irradiation.

Sensitivity and integration in a visual pathway for circadian entrainment in the hamster (Mesocricetus auratus).

PubMed Central

Nelson, D E; Takahashi, J S

1991-01-01

1. Light-induced phase shifts of the circadian rhythm of wheel-running activity were used to measure the photic sensitivity of a circadian pacemaker and the visual pathway that conveys light information to it in the golden hamster (Mesocricetus auratus). The sensitivity to stimulus irradiance and duration was assessed by measuring the magnitude of phase-shift responses to photic stimuli of different irradiance and duration. The visual sensitivity was also measured at three different phases of the circadian rhythm. 2. The stimulus-response curves measured at different circadian phases suggest that the maximum phase-shift is the only aspect of visual responsivity to change as a function of the circadian day. The half-saturation constants (sigma) for the stimulus-response curves are not significantly different over the three circadian phases tested. The photic sensitivity to irradiance (1/sigma) appears to remain constant over the circadian day. 3. The hamster circadian pacemaker and the photoreceptive system that subserves it are more sensitive to the irradiance of longer-duration stimuli than to irradiance of briefer stimuli. The system is maximally sensitive to the irradiance of stimuli of 300 s and longer in duration. A quantitative model is presented to explain the changes that occur in the stimulus-response curves as a function of photic stimulus duration. 4. The threshold for photic stimulation of the hamster circadian pacemaker is also quite high. The threshold irradiance (the minimum irradiance necessary to induce statistically significant responses) is approximately 10(11) photons cm-2 s-1 for optimal stimulus durations. This threshold is equivalent to a luminance at the cornea of 0.1 cd m-2. 5. We also measured the sensitivity of this visual pathway to the total number of photons in a stimulus. This system is maximally sensitive to photons in stimuli between 30 and 3600 s in duration. The maximum quantum efficiency of photic integration occurs in 300 s

The insecticide buprofezin induces morphological transformation and kinetochore-positive micronuclei in cultured Syrian hamster embryo cells in the absence of detectable DNA damage.

PubMed

Herrera, L A; Ostrosky-Wegman, P; Schiffmann, D; Chen, Q Y; Ziegler-Skylakakis, K; Andrae, U

1993-11-01

The insecticide buprofezin was examined for its genotoxicity in cultured Syrian hamster embryo cells in order to better understand the mechanisms underlying the genotoxicity of the compound in mammalian cells. Exposure to buprofezin concentrations of 12.5-100 microM did not significantly affect the colony-forming ability of the cells, but did result in increased frequencies of morphologically transformed colonies. Treatment with buprofezin did not cause a detectable induction of DNA repair synthesis, an indicator of DNA damage, but significantly increased the frequency of micronuclei. Immunostaining of the cells with antikinetochore antibody (CREST antibody) showed that essentially all of the buprofezin-induced micronuclei were kinetochore-positive. The results suggest that morphological transformation of Syrian hamster embryo cells by buprofezin results from an interaction of the compound or a metabolite of it with the mitotic apparatus rather than from DNA damage.

Identifying Early Target Cells of Nipah Virus Infection in Syrian Hamsters

PubMed Central

Baseler, Laura; Scott, Dana P.; Saturday, Greg; Horne, Eva; Rosenke, Rebecca; Thomas, Tina; Meade-White, Kimberly; Haddock, Elaine; Feldmann, Heinz

2016-01-01

Background Nipah virus causes respiratory and neurologic disease with case fatality rates up to 100% in individual outbreaks. End stage lesions have been described in the respiratory and nervous systems, vasculature and often lymphoid organs in fatal human cases; however, the initial target organs of Nipah virus infection have not been identified. Here, we detected the initial target tissues and cells of Nipah virus and tracked virus dissemination during the early phase of infection in Syrian hamsters inoculated with a Nipah virus isolate from Malaysia (NiV-M) or Bangladesh (NiV-B). Methodology/Principal Findings Syrian hamsters were euthanized between 4 and 48 hours post intranasal inoculation and tissues were collected and analyzed for the presence of viral RNA, viral antigen and infectious virus. Virus replication was first detected at 8 hours post inoculation (hpi). Nipah virus initially targeted type I pneumocytes, bronchiolar respiratory epithelium and alveolar macrophages in the lung and respiratory and olfactory epithelium lining the nasal turbinates. By 16 hpi, virus disseminated to epithelial cells lining the larynx and trachea. Although the pattern of viral dissemination was similar for both virus isolates, the rate of spread was slower for NiV-B. Infectious virus was not detected in the nervous system or blood and widespread vascular infection and lesions within lymphoid organs were not observed, even at 48 hpi. Conclusions/Significance Nipah virus initially targets the respiratory system. Virus replication in the brain and infection of blood vessels in non-respiratory tissues does not occur during the early phase of infection. However, virus replicates early in olfactory epithelium and may serve as the first step towards nervous system dissemination, suggesting that development of vaccines that block virus dissemination or treatments that can access the brain and spinal cord and directly inhibit virus replication may be necessary for preventing central

Identifying Early Target Cells of Nipah Virus Infection in Syrian Hamsters.

PubMed

Baseler, Laura; Scott, Dana P; Saturday, Greg; Horne, Eva; Rosenke, Rebecca; Thomas, Tina; Meade-White, Kimberly; Haddock, Elaine; Feldmann, Heinz; de Wit, Emmie

2016-11-01

Nipah virus causes respiratory and neurologic disease with case fatality rates up to 100% in individual outbreaks. End stage lesions have been described in the respiratory and nervous systems, vasculature and often lymphoid organs in fatal human cases; however, the initial target organs of Nipah virus infection have not been identified. Here, we detected the initial target tissues and cells of Nipah virus and tracked virus dissemination during the early phase of infection in Syrian hamsters inoculated with a Nipah virus isolate from Malaysia (NiV-M) or Bangladesh (NiV-B). Syrian hamsters were euthanized between 4 and 48 hours post intranasal inoculation and tissues were collected and analyzed for the presence of viral RNA, viral antigen and infectious virus. Virus replication was first detected at 8 hours post inoculation (hpi). Nipah virus initially targeted type I pneumocytes, bronchiolar respiratory epithelium and alveolar macrophages in the lung and respiratory and olfactory epithelium lining the nasal turbinates. By 16 hpi, virus disseminated to epithelial cells lining the larynx and trachea. Although the pattern of viral dissemination was similar for both virus isolates, the rate of spread was slower for NiV-B. Infectious virus was not detected in the nervous system or blood and widespread vascular infection and lesions within lymphoid organs were not observed, even at 48 hpi. Nipah virus initially targets the respiratory system. Virus replication in the brain and infection of blood vessels in non-respiratory tissues does not occur during the early phase of infection. However, virus replicates early in olfactory epithelium and may serve as the first step towards nervous system dissemination, suggesting that development of vaccines that block virus dissemination or treatments that can access the brain and spinal cord and directly inhibit virus replication may be necessary for preventing central nervous system pathology.

Photodynamic therapy of hamster Greene melanoma in vitro and in vivo using bacteriochlorin-a as photosensitizer

NASA Astrophysics Data System (ADS)

Schuitmaker, J. J.; Van Best, Jaap A.; van Delft, J. L.; Jannink, J. E.; Oosterhuis, J. A.; Vrensen, Gijs F.; Ms Wolff-Rouendaal, Didi; Dubbelman, T. M.

1996-01-01

Efficient photodynamic therapy (PDT) of malignant melanoma may be possible with photosensitizers having absorption maxima in the far-red region e.g., above 700 nm. Bacteriochlorin a (BCA), a non toxic derivative of bacteriochlorphyllin a, has a high molecular absorption coefficient (32.000 M-1.cm-1) at 760 nm. At this wavelength tissue penetration of light is almost optimal and melanin absorption is relatively low. In several series of experiments BCA was proven to be a very effective photosensitizer, in vitro and in vivo. It is preferentially retained in experimental hamster Greene melanoma, rhabdomyosarcoma, RIF- and mamma tumors. Its fluorescence can be detected in vivo, thus enabling early tumor detection and it is rapidly cleared from the tissues which promises no, or minor skin photosensitivity. The effects of BCA-PDT were studied in vitro and in vivo using the heavily pigmented Hamster Greene Melanoma (HGM) cell line as a model. In vitro it was found that the uptake of BCA was time, concentration and temperature dependant. Upon illumination (10 Mw/cm2, 756 nm) after incubation with 2.5 (mu) g/ml BCA for 1 h, almost complete cell kill was obtained within seconds. Hamster Greene Melanoma implanted in the anterior eye chamber of rabbits is an accepted in vivo model for ocular melanoma. The effects of BCA-PDT using this model were studied by light- and electron microscopy. Immediately after PDT intracellular spaces were enlarged and blood vessels were clotted with swollen erythrocytes. Electron microscopy showed fused inner and outer membranes and affected cristae mitchondriales of some mitochondria. With time, the severity of tissue and cell damage increased. One day after irradiation tumor growth had stopped; fluorescein angiography showed non perfusion of the tumor. Histopathology showed almost complete tumor necrosis with occasionally viable cells at the tumor periphery. It is concluded that the direct mitochondrial damage and the vascular damage both

Control of intracellular ionic concentrations by mid-infrared laser irradiation

NASA Astrophysics Data System (ADS)

Takebe, G.; Yamauchi, T.; Shimizu, Y.; Dougakiuchi, T.

2018-02-01

We successfully induced intracellular ion concentration changes in live culture cells using mid-infrared laser irradiation. The laser used for irradiation was a quantum cascade laser with a wavelength of 6.1 micrometers. We tuned the power of the laser to be between 30 to 60 mW at the sample. Cell lines, namely HeLa and Chinese hamster ovary cell lines, were used. They were cultured on specially fabricated silicon-bottom dishes. Live cells were stained using ion-sensitive dyes such as Calcium Green-1. The mid-infrared light was incident on the cell samples from the bottom of the dish through the silicon plate, and fluorescence imaging of the ion concentrations was performed using an upright fluorescence microscope placed on top of the sample stage. The mid-infrared lasers were operated in the continuous wave mode and light irradiations onto the cells were temporally controlled using a mechanical shutter in a periodical on-and-off pattern in the second timescale. The cells showed oscillations in their ionic concentration, which was synchronized with the periodical mid-infrared irradiation, and the threshold power needed for evoking the ion concentration change was dependent on the cell types and ion species. These results demonstrated that mid-infrared light directly changed the ionic response within cells and had the ability to change cell functions.

Characterization of an N-Terminal Non-Core Domain of RAG1 Gene Disrupted Syrian Hamster Model Generated by CRISPR Cas9.

PubMed

Miao, Jinxin; Ying, Baoling; Li, Rong; Tollefson, Ann E; Spencer, Jacqueline F; Wold, William S M; Song, Seok-Hwan; Kong, Il-Keun; Toth, Karoly; Wang, Yaohe; Wang, Zhongde

2018-05-06

The accumulating evidence demonstrates that Syrian hamsters have advantages as models for various diseases. To develop a Syrian hamster ( Mesocricetus auratus ) model of human immunodeficiency caused by RAG1 gene mutations, we employed the CRISPR/Cas9 system and introduced an 86-nucleotide frameshift deletion in the hamster RAG1 gene encoding part of the N-terminal non-core domain of RAG1. Histological and immunohistochemical analyses demonstrated that these hamsters (referred herein as RAG1-86nt hamsters) had atrophic spleen and thymus, and developed significantly less white pulp and were almost completely devoid of splenic lymphoid follicles. The RAG1-nt86 hamsters had barely detectable CD3⁺ and CD4⁺ T cells. The expression of B and T lymphocyte-specific genes (CD3γ and CD4 for T cell-specific) and (CD22 and FCMR for B cell-specific) was dramatically reduced, whereas the expression of macrophage-specific (CD68) and natural killer (NK) cell-specific (CD94 and KLRG1) marker genes was increased in the spleen of RAG1-nt86 hamsters compared to wildtype hamsters. Interestingly, despite the impaired development of B and T lymphocytes, the RAG1-86nt hamsters still developed neutralizing antibodies against human adenovirus type C6 (HAdV-C6) upon intranasal infection and were capable of clearing the infectious viruses, albeit with slower kinetics. Therefore, the RAG1-86nt hamster reported herein (similar to the hypomorphic RAG1 mutations in humans that cause Omenn syndrome), may provide a useful model for studying the pathogenesis of the specific RAG1-mutation-induced human immunodeficiency, the host immune response to adenovirus infection and other pathogens as well as for evaluation of cell and gene therapies for treatment of this subset of RAG1 mutation patients.

Identification of hamster inducible nitric oxide synthase (iNOS) promoter sequences that influence basal and inducible iNOS expression

PubMed Central

Saldarriaga, Omar A.; Travi, Bruno L.; Choudhury, Goutam Ghosh; Melby, Peter C.

2012-01-01

IFN-γ/LPS-activated hamster (Mesocricetus auratus) macrophages express significantly less iNOS (NOS2) than activated mouse macrophages, which contributes to the hamster's susceptibility to intracellular pathogens. We determined a mechanism responsible for differences in iNOS promoter activity in hamsters and mice. The HtPP (1.2 kb) showed low basal and inducible promoter activity when compared with the mouse, and sequences within a 100-bp region (−233 to −133) of the mouse and hamster promoters influenced this activity. Moreover, within this 100 bp, we identified a smaller region (44 bp) in the mouse promoter, which recovered basal promoter activity when swapped into the hamster promoter. The mouse homolog (100-bp region) contained a cis-element for NF-IL-6 (−153/−142), which was absent in the hamster counterpart. EMSA and supershift assays revealed that the hamster sequence did not support the binding of NF-IL-6. Introduction of a functional NF-IL-6 binding sequence into the hamster promoter or its alteration in the mouse promoter revealed the critical importance of this transcription factor for full iNOS promoter activity. Furthermore, the binding of NF-IL-6 to the iNOS promoter (−153/−142) in vivo was increased in mouse cells but was reduced in hamster cells after IFN-γ/LPS stimulation. Differences in the activity of the iNOS promoters were evident in mouse and hamster cells, so they were not merely a result of species-specific differences in transcription factors. Thus, we have identified unique DNA sequences and a critical transcription factor, NF-IL-6, which contribute to the overall basal and inducible expression of hamster iNOS. PMID:22517919

A low, adaptive dose of gamma-rays reduced the number and altered the spectrum of S1- mutants in human-hamster hybrid AL cells

NASA Technical Reports Server (NTRS)

Ueno, A. M.; Vannais, D. B.; Gustafson, D. L.; Wong, J. C.; Waldren, C. A.

1996-01-01

We examined the effects of a low, adaptive dose of 137Cs-gamma-irradiation (0.04 Gy) on the number and kinds of mutants induced in AL human-hamster hybrid cells by a later challenge dose of 4 Gy. The yield of S1- mutants was significantly less (by 53%) after exposure to both the adaptive and challenge doses compared to the challenge dose alone. The yield of hprt- mutants was similarly decreased. Incubation with cycloheximide (CX) or 3-aminobenzamide largely negated the decrease in mutant yield. The adaptive dose did not perturb the cell cycle, was not cytotoxic, and did not of itself increase the mutant yield above background. The adaptive dose did, however, alter the spectrum of S1- mutants from populations exposed only to the adaptive dose, as well as affecting the spectrum of S1- mutants generated by the challenge dose. The major change in both cases was a significant increase in the proportion of complex mutations compared to small mutations and simple deletions.

Lymphocyte function in experimental endemic syphilis of Syrian hamsters.

PubMed Central

Bagasra, O; Kushner, H; Hashemi, S

1985-01-01

We have studied the changes in the lymph nodes, spleen and thymus that occur in inbred LSH Syrian hamsters infected with Treponema pallidum Bosnia A, the causative agent of endemic syphilis, as well as the B-cell responses of these infected animals to helper T-cell independent and dependent antigens. The lymph nodes increased significantly in weight up to 6 weeks after infection, and contained viable treponemes. No significant changes in the spleen weight were observed, and no viable treponemes could be recovered from the spleen. However, the size of the thymus decreased steadily during the course of the disease. The relative number of Ig+ cells (B cells) increased in the spleen and regional lymph nodes, whereas the relative number of T cells decreased during the course of infection. In both the spleen and lymph nodes, the relative number of macrophages increased initially and decreased thereafter in the form of a bell-shaped curve showing a peak at 4-6 weeks of infection. The ability of splenic lymphocytes from infected hamsters to mount a primary PFC response to pneumococcal polysaccharide type III (SIII), a helper T-cell independent antigen, was elevated throughout the course of infection. However, the splenic PFC response to sheep erythrocytes (SRBC), a helper T-cell dependent antigen, was increased only during the first 4 weeks of infection and progressively decreased thereafter. The PFC responses of infected lymph node lymphocytes to both SIII and SRBC were increased during the first 4 weeks and decreased thereafter. These data suggested that atrophy of the thymus seen in syphilitic infection is accompanied by the complex losses of subsets of T cells and altered B-cell functions. An early loss of suppressor T cells in both the lymph nodes and spleen occurs concomitantly with a loss of T helper cells and heterologous (treponema-unrelated) B-cell functions in the lymph nodes. Helper T cells are lost from the spleen only in the later stages of infection, whereas

Expression of vascular endothelial growth factor does not promote transformation but confers a growth advantage in vivo to Chinese hamster ovary cells.

PubMed Central

Ferrara, N; Winer, J; Burton, T; Rowland, A; Siegel, M; Phillips, H S; Terrell, T; Keller, G A; Levinson, A D

1993-01-01

Vascular endothelial growth factor (VEGF) is a mitogen with a specificity for endothelial cells in vitro and an angiogenic inducer in vivo. We tested the hypothesis that VEGF may confer on expressing cells a growth advantage in vivo. Dihydrofolatereductase--Chinese hamster ovary cells were transfected with expression vectors which direct the constitutive synthesis of VEGF. Neither the expression nor the exogenous administration of VEGF stimulated anchorage-dependent or anchorage-independent growth of Chinese hamster ovary cells in vitro. However, VEGF-expressing clones, unlike control cells, demonstrated an ability to proliferate in nude mice. Histologic examination revealed that the proliferative lesions were compact, well vascularized, and nonedematous. Ultrastructural analysis revealed that capillaries within the lesions were of the continuous type. These findings indicate that the expression of VEGF may confer on cells the ability to grow in vivo in the absence of transformation by purely paracrine mechanisms. Since VEGF is a widely distributed protein, this property may have relevance for a variety of physiological and pathological proliferative processes. Images PMID:8423215

Antigenic specificity and morphologic characteristics of Chlamydia trachomatis, strain SFPD, isolated from hamsters with proliferative ileitis.

PubMed

Fox, J G; Stills, H F; Paster, B J; Dewhirst, F E; Yan, L; Palley, L; Prostak, K

1993-10-01

Profound diarrhea associated with proliferating intestinal cells containing intraepithelial campylobacter-like organisms (ICLO) occurs in a variety of mammalian hosts, particularly swine and hamsters. Recently, intracellular bacteria were isolated from proliferative intestinal tissue of hamsters and propagated in intestine cell line 407. Oral inoculation of hamsters with cell culture lysates containing these organisms reproduced the disease in susceptible hamsters. In the present study, an intracellular bacterium from the INT 407 cell line was shown by a variety of techniques to be a member of the genus Chlamydia and has been designated Chlamydia sp. strain SFPD. McCoy cells infected with Chlamydia sp. strain SFPD demonstrated bright fluorescent-stained intracytoplasmic inclusions when examined with fluorescein-labeled species-specific C. trachomatis monoclonal antibodies. The organism also reacted to fluorescein-labeled polyclonal but not monoclonal ICLO "omega" antisera. Ultrastructural examination of the Chlamydia sp. strain SFPD from McCoy cells revealed electrondense elementary bodies and a less electron-dense reticulate-like body that was circular; both features are consistent in morphology to developmental forms of Chlamydia and do not conform to ICLO morphology. Molecular studies, 16S ribosomal sequence analysis, and sequencing of the outer membrane protein confirmed that the isolate is a C. trachomatis closely related to the mouse pneumonitis strain of C. trachomatis.

Role of isolated and clustered DNA damage and the post-irradiating repair process in the effects of heavy ion beam irradiation.

PubMed

Tokuyama, Yuka; Furusawa, Yoshiya; Ide, Hiroshi; Yasui, Akira; Terato, Hiroaki

2015-05-01

Clustered DNA damage is a specific type of DNA damage induced by ionizing radiation. Any type of ionizing radiation traverses the target DNA molecule as a beam, inducing damage along its track. Our previous study showed that clustered DNA damage yields decreased with increased linear energy transfer (LET), leading us to investigate the importance of clustered DNA damage in the biological effects of heavy ion beam radiation. In this study, we analyzed the yield of clustered base damage (comprising multiple base lesions) in cultured cells irradiated with various heavy ion beams, and investigated isolated base damage and the repair process in post-irradiation cultured cells. Chinese hamster ovary (CHO) cells were irradiated by carbon, silicon, argon and iron ion beams with LETs of 13, 55, 90 and 200 keV µm(-1), respectively. Agarose gel electrophoresis of the cells with enzymatic treatments indicated that clustered base damage yields decreased as the LET increased. The aldehyde reactive probe procedure showed that isolated base damage yields in the irradiated cells followed the same pattern. To analyze the cellular base damage process, clustered DNA damage repair was investigated using DNA repair mutant cells. DNA double-strand breaks accumulated in CHO mutant cells lacking Xrcc1 after irradiation, and the cell viability decreased. On the other hand, mouse embryonic fibroblast (Mef) cells lacking both Nth1 and Ogg1 became more resistant than the wild type Mef. Thus, clustered base damage seems to be involved in the expression of heavy ion beam biological effects via the repair process. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth

PubMed Central

Opoku-Acheampong, Alexander B.; Penugonda, Kavitha; Lindshield, Brian L.

2016-01-01

Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth. PMID:27272436

Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth.

PubMed

Opoku-Acheampong, Alexander B; Penugonda, Kavitha; Lindshield, Brian L

2016-01-01

Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth.

Measuring the spectrum of mutation induced by nitrogen ions and protons in the human-hamster hybrid cell line A(L)C

NASA Technical Reports Server (NTRS)

Kraemer, S. M.; Kronenberg, A.; Ueno, A.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

2000-01-01

Astronauts can be exposed to charged particles, including protons, alpha particles and heavier ions, during space flights. Therefore, studying the biological effectiveness of these sparsely and densely ionizing radiations is important to understanding the potential health effects for astronauts. We evaluated the mutagenic effectiveness of sparsely ionizing 55 MeV protons and densely ionizing 32 MeV/nucleon nitrogen ions using cells of two human-hamster cell lines, A(L) and A(L)C. We have previously characterized a spectrum of mutations, including megabase deletions, in human chromosome 11, the sole human chromosome in the human-hamster hybrid cell lines A(L)C and A(L). CD59(-) mutants have lost expression of a human cell surface antigen encoded by the CD59 gene located at 11p13. Deletion of genes located on the tip of the short arm of 11 (11p15.5) is lethal to the A(L) hybrid, so that CD59 mutants that lose the entire chromosome 11 die and escape detection. In contrast, deletion of the 11p15.5 region is not lethal in the hybrid A(L)C, allowing for the detection of chromosome loss or other chromosomal mutations involving 11p15.5. The 55 MeV protons and 32 MeV/nucleon nitrogen ions were each about 10 times more mutagenic per unit dose at the CD59 locus in A(L)C cells than in A(L) cells. In the case of nitrogen ions, the mutations observed in A(L)C cells were predominantly due to chromosome loss events or 11p deletions, often containing a breakpoint in the pericentromeric region. The increase in the CD59(-) mutant fraction for A(L)C cells exposed to protons was associated with either translocation of portions of 11q onto a hamster chromosome, or discontinuous or "skipping" mutations. We demonstrate here that A(L)C cells are a powerful tool that will aid in the understanding of the mutagenic effects of different types of ionizing radiation.

ULTRASTRUCTURE OF THE NUCLEOLUS DURING THE CHINESE HAMSTER CELL CYCLE

PubMed Central

Noel, J. S.; Dewey, W. C.; Abel, J. H.; Thompson, R. P.

1971-01-01

Changes in the structure of the nucleolus during the cell cycle of the Chinese hamster cell in vitro were studied. Quantitative electron microscopic techniques were used to establish the size and volume changes in nucleolar structures. In mitosis, nucleolar remnants, "persistent nucleoli," consisting predominantly of ribosome-like granular material, and a granular coating on the chromosomes were observed. Persistent nucleoli were also observed in some daughter nuclei as they were leaving telophase and entering G1. During very early G1, a dense, fibrous material characteristic of interphase nucleoli was noted in the nucleoplasm of the cells. As the cells progressed through G1, a granular component appeared which was intimately associated with the fibrous material. By the middle of G1, complete, mature nucleoli were present. The nucleolar volume enlarged by a factor of two from the beginning of G1 to the middle of S primarily due to the accumulation of the granular component. During the G2 period, there was a dissolution or breakdown of the nucleolus prior to the entry of the cells into mitosis. Correlations between the quantitative aspects of this study and biochemical and cytochemical data available in the literature suggest the following: nucleolar reformation following division results from the activation of the nucleolar organizer regions which transcribe for RNA first appearing in association with protein as a fibrous component (45S RNA) and then later as a granular component (28S and 32S RNA). PMID:4933472

Inhibition of apoptosis using exosomes in Chinese hamster ovary cell culture.

PubMed

Han, Seora; Rhee, Won Jong

2018-05-01

Animal cell culture technology for therapeutic protein production has shown significant improvement over the last few decades. Chinese hamster ovary (CHO) cells have been widely adapted for the production of biopharmaceutical drugs. In the biopharmaceutical industry, it is crucial to develop cell culture media and culturing conditions to achieve the highest productivity and quality. However, CHO cells are significantly affected by apoptosis in the bioreactors, resulting in a substantial decrease in product quantity and quality. Thus, to overcome the obstacle of apoptosis in CHO cell culture, it is critical to develop a novel method that does not have minimal concern of safety or cost. Herein, we showed for the first time that exosomes, which are nano-sized extracellular vesicles, derived from CHO cells inhibited apoptosis in CHO cell culture when supplemented to the culture medium. Flow cytometric and microscopic analyses revealed that substantial amounts of exosomes were delivered to CHO cells. Higher cell viability after staurosporine treatment was observed by exosome supplementation (67.3%) as compared to control (41.1%). Furthermore, exosomes prevented the mitochondrial membrane potential loss and caspase-3 activation, meaning that the exosomes enhanced cellular activities under pro-apoptotic condition. As the exosomes supplements are derived from CHO cells themselves, it is not only beneficial for the biopharmaceutical productivity of CHO cell culture to inhibit apoptosis, but also from a regulatory standpoint to diminish any safety concerns. Thus, we conclude that the method developed in this research may contribute to the biopharmaceutical industry where minimizing apoptosis in CHO cell culture is beneficial. © 2018 Wiley Periodicals, Inc.

Identification of shed proteins from Chinese hamster ovary cells: Application of statistical confidence using human and mouse protein databases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahram, Mamoun; Strittmatter, Eric F.; Monroe, Matthew E.

The shedding process releases ligands, receptors, and other proteins from the surface of the cell and is a mechanism whereby cells communicate. Even though altered regulation of this process has been implicated in several diseases, global approaches to evaluate shed proteins have not been developed. A goal of this study was to identify global changes in shed proteins in media taken from cells exposed to low-doses of radiation in an effort to develop a fundamental understanding of the bystander response. CHO cells were chosen for this study because they have been widely used for radiation studies and since they havemore » been reported to respond to radiation by releasing factors into the media that cause genomic instability and cytotoxicity in unexposed cells, i.e., a bystander effect. Media samples taken for irradiated cells were evaluated using a combination of tandem- and FTICR-mass spectrometry analysis. Since the hamster genome has not been sequenced, mass spectrometry data was searched against the mouse and human proteins databases. Nearly 150 proteins that were identified by tandem mass spectrometry were confirmed by FTICR. When both types of mass spectrometry data were evaluated with a new confidence scoring tool, which is based on discriminant analyses, about 500 protein were identified. Approximately 20% of these identifications were either integral membrane proteins or membrane associated proteins, suggesting that they were derived from the cell surface, hence were likely shed. However, estimates of quantitative changes, based on two independent mass spectrometry approaches, did not identify any protein abundance changes attributable to the bystander effect. Results from this study demonstrate the feasibility of global evaluation of shed proteins using mass spectrometry in conjunction with cross-species protein databases and that significant improvement in peptide/protein identifications is provided by the confidence scoring tool.« less

Radiosensitivity and thermosensitization of thermotolerant Chinese hamster cells and RIF-1 tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartson-Eaton, M.; Malcolm, A.W.; Hahn, G.M.

1984-07-01

CHO cells subline HA-1 were made thermotolerant by a priming heat treatment(43/sup 0/C, 30 min). Later, 4, 16, or 24 hr, they were either irradiated or heated (43/sup 0/C, 30 min) and irradiated. Thermotolerance had no effect on the radiation sensitivity of the cells as measured by the D/sub 0/ value of the clonogenic survival curve. However the N value of the curve (width of shoulder) showed a significant increase at 24 hr, indicating an increased capacity to accumulate sublethal damage. The same priming treatment was given to RIF-1 tumors growing in C3H mice. Later, 24 hr, when the tumorsmore » were either irradiated or heated (43/sup 0/C, 30 min) and irradiated, it was found that thermotolerance had no effect on the radiosensitivity of the cells as measured by in vitro assay. However, thermal radiosensitization was not apparent 24 hr after the priming treatment.« less

Effects of preventing O-glycosylation on the secretion of human chorionic gonadotropin in Chinese hamster ovary cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matzuk, M.M.; Krieger, M.; Corless, C.L.

1987-09-01

Human chorionic gonadotropin (hCG) is a member of a family of heterodimeric glycoprotein hormones that have a common ..cap alpha.. subunit but differ in their hormone-specific ..beta..-subunits. The ..beta.. subunit of hCG (hCG..beta..) is unique among the ..beta.. subunits in that it contains four mucin-like O-linked oligosaccharides attached to a carboxyl-terminal extension. To study the effects of O-glycosylation on the secretion and assembly of hCG, expression vectors containing either hCG..beta.. gene alone or together with the hCG..cap alpha.. gene were transfected into a mutant Chinese hamster ovary cell line, 1d1D, which exhibits a reversible defect in O-glycosylation. The results revealmore » that hCG..beta.. can be secreted normally in the absence of its O-linked oligosaccharides. hCG..beta.. devoid of O-linked carbohydrate can also combine efficiently with hCG..cap alpha.. and be secreted as an intact dimer. The authors conclude that in Chinese hamster ovary cells, the hCG..beta.. O-linked chains play no role in the assembly and secretion of hCG. The normal and O-linked oligosaccharide-deficient forms of hCG secreted by these cells should prove useful in examining the role of O-linked chains on the biological function of hCG.« less

Zika virus infection of adult and fetal STAT2 knock-out hamsters.

PubMed

Siddharthan, Venkatraman; Van Wettere, Arnaud J; Li, Rong; Miao, Jinxin; Wang, Zhongde; Morrey, John D; Julander, Justin G

2017-07-01

Zika virus (ZIKV) infection was investigated in adult and fetal STAT2 knock-out (KO) hamsters. Subcutaneous injection of ZIKV of adults resulted in morbidity, mortality, and infection of the uterus, placenta, brain, spinal cord, and testicles, thus providing an opportunity to evaluate congenital ZIKV infection in a second rodent species besides mice. ZIKV-infected cells with morphologies of Sertoli cells and spermatogonia were observed in the testes, which may have implications for sexual transmission and male sterility. Neonates exposed as fetuses to ZIKV at 8 days post-coitus were not smaller than controls. Nevertheless, infectious virus and ZIKV RNA was detected in some, but not all, placentas and fetal brains of KO hamsters. STAT2 KO hamsters may be useful for addressing sexual transmission, pathogenesis, routes of fetal infection, and neurological disease outcomes, and may also be used in antiviral or vaccine studies to identify intervention strategies. Copyright © 2017. Published by Elsevier Inc.

Effects of caffeine on radiation-induced phenomena associated with cell- cycle traverse of mammalian cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walters, R.A.; Gurley, L.R.; Tobby, R.A.

1974-02-01

Caffeine induced a state of G/sub 1/ arrest when added to an exponentially growing culture of Chinese hamster cells (line CHO). In addition to its effect on cell-cycle traverse, caffeine ameliorated a number of the responses of cells to ionizing radiation. The duration of the division delay period following x-irradiation of caffeine-treated cells was reduced, and the magnitude of reduction was dependent on caffeine concentration. Cells irradiated during the DNA synthetic phase in the presence of caffeine were delayed less in their exit from S, measured autoradiographically, and the radiation-induced reduction of radioactive thymidine incorporation into DNA was lessened. Cellsmore » synchronized by isoleucine deprivation, while being generally less sensitive to the effects of ionizing radiation than mitotically synchronized cells, were equally responsive to the effects of caffeine. The x-rayinduced reduction of phosphorylation of lysine-rich histone F1 was less in caffeine-treated cells than in untreated cells. Finally, survival after irradiation was only slightly reduced in caffeinetreated cells. A possible role of cyclic AMP in cell-cycle traverse of irradiated cells is discussed. (auth)« less

Male hamster preference for odors of female hamster vaginal discharges: studies of experiential and hormonal determinants.

PubMed

Gregory, E; Engel, K; Pfaff, D

1975-07-01

Male hamsters approach sources of odors from female hamster vaginal discharges and spend significantly more time around these odor sources than around control locations in the test box. This preference for female hamster vaginal odors appears in sexually inexperienced as well as experienced males, even in individuals isolated from females since the time of weaning. Castration significantly reduces the sex odor preference, and treatment with testosterone propionate partially restores it.

Pleural lesions in Syrian golden hamsters and Fischer-344 rats following intrapleural instillation of man-made ceramic or glass fibers.

PubMed

Everitt, J I; Bermudez, E; Mangum, J B; Wong, B; Moss, O R; Janszen, D; Rutten, A A

1994-01-01

The mesothelium is a target of the toxic and carcinogenic effects of certain natural mineral and man-made fibers. Long-term inhalation of a ceramic fiber (RCF-1) results in a high incidence of pleural mesotheliomas in Syrian golden hamsters but not in identically exposed Fischer-344 rats. The present study compared the histopathology of the early pleural response in rats and hamsters instilled with artificial fibers. Groups of Syrian golden hamsters and Fischer-344 rats were instilled with ceramic (RCF-1) or glass (MMVF-10) fibers directly into the pleural space. Each species received approximately equal numbers of long, thin fibers per g body weight. Fiber-induced lesions were compared 7 and 28 days postinstillation. Both hamsters and rats developed qualitatively similar dose-dependent inflammatory lesions that were not fiber-type specific. Both species developed fibrosis in conjunction with inflammation in the visceral pleura, but a striking interspecies difference was noted in the pattern of mesothelial cell response. Hamsters developed greater surface mesothelial cell proliferation and had focal aggregates of mesothelial cells embedded deep within regions of visceral pleural fibrosis. It is hypothesized from the present study that the marked fiber-induced proliferative mesothelial cell response of the hamster visceral pleura may explain the high number of pleural mesotheliomas found in long-term fiber studies in this species.

Ionotropic glutamate receptor GluR2/3-immunoreactive neurons in the cat, rabbit, and hamster superficial superior colliculus.

PubMed

Park, Won-Mee; Kim, Min-Jeong; Jeon, Chang-Jin

2004-06-01

Ionotropic glutamate receptor (GluR) subtypes occur in various types of cells in the central nervous system. We studied the distribution of AMPA glutamate receptor subtype GluR2/3 in the superficial layers of cat, rabbit, and hamster superior colliculus (SC) with antibody immunocytochemistry and the effect of enucleation on this distribution. Furthermore, we compared this labeling to that of calbindin D28K and parvalbumin. Anti-GluR2/3-immunoreactive (IR) cells formed a dense band of labeled cells within the lower superficial gray layer (SGL) and upper optic layer (OL) in the cat SC. By contrast, GluR2/3-IR cells formed a dense band within the upper OL in the rabbit and within the OL in the hamster SC. Calbindin D28K-IR cells are located in three layers in the SC: one within the zonal layer (ZL) and the upper SGL in all three animals, a second within the lower OL and upper IGL in the cat, within the IGL in the rabbit and within the OL in the hamster, and a third within the deep gray layer (DGL) in all three animals. Many parvalbumin-IR neurons were found within the lower SGL and upper OL. Thus, the GluR2/3-IR band was sandwiched between the first and second layers of calbindin D28K-IR cells in the cat and rabbit SC while the distribution of GluR2/3-IR cells in the hamster matches the second layer of calbindin D28K-IR cells. The patterned distribution of GluR2/3-IR cells overlapped the tier of parvalbumin-IR neurons in cat, but only partially overlapped in hamster and rabbit. Two-color immunofluorescence revealed that more than half (55.1%) of the GluR2/3-IR cells in the hamster SC expressed calbindin D28K. By contrast, only 9.9% of GluR2/3-IR cells expressed calbindin D28K in the cat. Double-labeled cells were not found in the rabbit SC. Some (4.8%) GluR2/3-IR cells in the cat SC also expressed parvalbumin, while no GluR2/3-IR cells in rabbit and hamster SC expressed parvalbumin. In this dense band of GluR2/3, the majority of labeled cells were small to medium

Immune response in the hamster: definition of a novel IgG not expressed in all hamster strains.

PubMed Central

Coe, J E; Schell, R F; Ross, M J

1995-01-01

A new IgG isotype is described in serum from Syrian hamsters. This 7S-IgG is called IgG3 and was isolated from IgG1 and IgG2 because of its great affinity for protein A. The unique antigenic determinants of IgG3 were identified with a specific rabbit antisera. IgG3 is the least expressed IgG subclass in Syrian hamsters, but serum levels increase more than 10-fold after immunization or infection. Although found in all tested outbred strains, IgG3 is expressed in only some of the commercially available inbred strains of Syrian hamsters. Five inbred hamster strains were examined, and in three strains (CB, LHC and MHA) IgG3 was not detected in normal serum or in immune serum, indicating serum levels at least 100-fold less than other normal inbred/outbred hamsters. The results of breeding experiments suggests a single gene defect is responsible for this non-expression of IgG3. Immunodeficiency was not associated with this IgG3 deficiency. Selective deficiencies of immunoglobulin classes/subclasses in experimental animals are rare. The evolution of a similar IgG3 deficiency in these three hamster strains during inbreeding suggests a novel and efficient mechanism for regulation of IgG3 synthesis in the Syrian hamster. Images Figure 2 Figure 3 Figure 5 PMID:7590875

Intestinal transfer of choline in rat and hamster

PubMed Central

Sanford, P. A.; Smyth, D. H.

1971-01-01

1. The transfer of choline was studied with sacs of everted intestine of rat and hamster. 2. The choline transfer can be divided into two components, a diffusion process and a saturable process. The latter plays a relatively greater part at low concentrations of choline, which include the physiological concentration in the plasma. The saturable process is better seen in the hamster than in the rat. 3. Intestinal transfer of choline is influenced by substances altering the availability of energy in the cell, and by some substances chemically or pharmacologically related to choline. These findings are consistent with some kind of specific mechanism for choline transfer. 4. Part of the choline taken up by the cell appears as a metabolite not yet identified. The formation of the metabolite is a saturable process and is abolished by anaerobic conditions and by homogenization. 5. The results are also discussed in relation to parameters of transfer. PMID:5090994

Molecular Prerequisites for Diminished Cold Sensitivity in Ground Squirrels and Hamsters.

PubMed

Matos-Cruz, Vanessa; Schneider, Eve R; Mastrotto, Marco; Merriman, Dana K; Bagriantsev, Sviatoslav N; Gracheva, Elena O

2017-12-19

Thirteen-lined ground squirrels and Syrian hamsters are known for their ability to withstand cold during hibernation. We found that hibernators exhibit cold tolerance even in the active state. Imaging and electrophysiology of squirrel somatosensory neurons reveal a decrease in cold sensitivity of TRPM8-expressing cells. Characterization of squirrel and hamster TRPM8 showed that the channels are chemically activated but exhibit poor activation by cold. Cold sensitivity can be re-introduced into squirrel and hamster TRPM8 by transferring the transmembrane domain from the cold sensitive rat ortholog. The same can be achieved in squirrel TRPM8 by mutating only six amino acids. Reciprocal mutations suppress cold sensitivity of the rat ortholog, supporting functional significance of these residues. Our results suggest that ground squirrels and hamsters exhibit reduced cold sensitivity, partially due to modifications in the transmembrane domain of TRPM8. Our study reveals molecular adaptations that accompany cold tolerance in two species of mammalian hibernators. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Cultured Chinese hamster cells undergo apoptosis after exposure to cold but nonfreezing temperatures.

PubMed

Nagle, W A; Soloff, B L; Moss, A J; Henle, K J

1990-08-01

Cultured Chinese hamster V79 fibroblast cells at the transition from logarithmic to stationary growth have been shown to undergo apoptosis (programmed cell death) after cold shock [B. L. Soloff, W. A. Nagle, A. J. Moss, Jr., K. J. Henle, and J. T. Crawford, Biochem. Biophys. Res. Commun. 145, 876-883 (1987)]. In this report, we show that about 95% of the cell population was susceptible to cold-induced apoptosis, and the amount of cell killing was dependent on the duration of hypothermia. Cells treated for 0-90 min at 0 degrees C exhibited an exponential survival curve with a D0 of 32 min; thus, even short exposures to the cold (e.g., 5 min) produced measurable cell killing. The cold-induced injury was not produced by freezing, because similar results were observed at 6 degrees C, and cell killing was not influenced by the cryoprotective agent dimethyl sulfoxide. Cold-induced apoptosis was inhibited by rewarming at 23 degrees C, compared to 37 degrees C, by inhibitors of macromolecular synthesis, such as cycloheximide, and by 0.8 mM zinc sulfate. The results suggest that apoptosis represents a new manifestation of cell injury after brief exposure to 0-6 degrees C hypothermia.

Centriole distribution during tripolar mitosis in Chinese hamster ovary cells

PubMed Central

1984-01-01

During bipolar mitosis a pair of centrioles is distributed to each cell but the activities of the two centrioles within the pair are not equivalent. The parent is normally surrounded by a cloud of pericentriolar material that serves as a microtubule-organizing center. The daughter does not become associated with pericentriolar material until it becomes a parent in the next cell cycle (Rieder, C.L., and G. G. Borisy , 1982, Biol. Cell., 44:117-132). We asked whether the microtubule-organizing activity associated with a centriole was dependent on its becoming a parent. We induced multipolar mitosis in Chinese hamster ovary cells by treatment with 0.04 micrograms/ml colcemid for 4 h. After recovery from this colcemid block, the majority of cells divided into two, but 40% divided into three and 2% divided into four. The tripolar mitotic cells were examined by antitubulin immunofluorescence and by high voltage electron microscopy of serial thick (0.25-micron) sections. The electron microscope analysis showed that centriole number was conserved and that the centrioles were distributed among the three spindle poles, generally in a 2:1:1 or 2:2:0 pattern. The first pattern shows that centriole parenting is not prerequisite for association with pole function; the second pattern indicates that centrioles per se are not required at all. However, the frequency of midbody formation and successful division was higher when centrioles were present in the 2:1:1 pattern. We suggest that the centrioles may help the proper distribution and organization of the pericentriolar cloud, which is needed for the formation of a functional spindle pole. PMID:6373793

Hypothalamic Ventricular Ependymal Thyroid Hormone Deiodinases Are an Important Element of Circannual Timing in the Siberian Hamster (Phodopus sungorus)

PubMed Central

Bolborea, Matei; Wilson, Dana; Mercer, Julian G.; Ebling, Francis J. P.; Morgan, Peter J.; Barrett, Perry

2013-01-01

Exposure to short days (SD) induces profound changes in the physiology and behaviour of Siberian hamsters, including gonadal regression and up to 30% loss in body weight. In a continuous SD environment after approximately 20 weeks, Siberian hamsters spontaneously revert to a long day (LD) phenotype, a phenomenon referred to as the photorefractory response. Previously we have identified a number of genes that are regulated by short photoperiod in the neuropil and ventricular ependymal (VE) cells of the hypothalamus, although their importance and contribution to photoperiod induced physiology is unclear. In this refractory model we hypothesised that the return to LD physiology involves reversal of SD expression levels of key hypothalamic genes to their LD values and thereby implicate genes required for LD physiology. Male Siberian hamsters were kept in either LD or SD for up to 39 weeks during which time SD hamster body weight decreased before increasing, after more than 20 weeks, back to LD values. Brain tissue was collected between 14 and 39 weeks for in situ hybridization to determine hypothalamic gene expression. In VE cells lining the third ventricle, expression of nestin, vimentin, Crbp1 and Gpr50 were down-regulated at 18 weeks in SD photoperiod, but expression was not restored to the LD level in photorefractory hamsters. Dio2, Mct8 and Tsh-r expression were altered by SD photoperiod and were fully restored, or even exceeded values found in LD hamsters in the refractory state. In hypothalamic nuclei, expression of Srif and Mc3r mRNAs was altered at 18 weeks in SD, but were similar to LD expression values in photorefractory hamsters. We conclude that in refractory hamsters not all VE cell functions are required to establish LD physiology. However, thyroid hormone signalling from ependymal cells and reversal of neuronal gene expression appear to be essential for the SD refractory response. PMID:23637944

Influence of caffeine on X-ray-induced killing and mutation in V79 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhattacharjee, S.B.; Bhattacharyya, N.; Chatterjee, S.

1987-02-01

Effects produced by caffeine on X-irradiated Chinese hamster V79 cells depended on the growth conditions of the cells. For exponentially growing cells, nontoxic concentrations of caffeine decreased the shoulder width from the survival curve, but the slope remained unchanged. The yield of mutants under the same conditions also remained unaffected. In case of density-inhibited cells, delaying trypsinization for 24 h after X irradiation increased the survival and decreased the yield of mutants. The presence of caffeine during this incubation period inhibited such recovery and significantly increased the yield of X-ray-induced mutants.

Depletion of Alveolar Macrophages Does Not Prevent Hantavirus Disease Pathogenesis in Golden Syrian Hamsters.

PubMed

Hammerbeck, Christopher D; Brocato, Rebecca L; Bell, Todd M; Schellhase, Christopher W; Mraz, Steven R; Queen, Laurie A; Hooper, Jay W

2016-07-15

Andes virus (ANDV) is associated with a lethal vascular leak syndrome in humans termed hantavirus pulmonary syndrome (HPS). The mechanism for the massive vascular leakage associated with HPS is poorly understood; however, dysregulation of components of the immune response is often suggested as a possible cause. Alveolar macrophages are found in the alveoli of the lung and represent the first line of defense to many airborne pathogens. To determine whether alveolar macrophages play a role in HPS pathogenesis, alveolar macrophages were depleted in an adult rodent model of HPS that closely resembles human HPS. Syrian hamsters were treated, intratracheally, with clodronate-encapsulated liposomes or control liposomes and were then challenged with ANDV. Treatment with clodronate-encapsulated liposomes resulted in significant reduction in alveolar macrophages, but depletion did not prevent pathogenesis or prolong disease. Depletion also did not significantly reduce the amount of virus in the lung of ANDV-infected hamsters but altered neutrophil recruitment, MIP-1α and MIP-2 chemokine expression, and vascular endothelial growth factor (VEGF) levels in hamster bronchoalveolar lavage (BAL) fluid early after intranasal challenge. These data demonstrate that alveolar macrophages may play a limited protective role early after exposure to aerosolized ANDV but do not directly contribute to hantavirus disease pathogenesis in the hamster model of HPS. Hantaviruses continue to cause disease worldwide for which there are no FDA-licensed vaccines, effective postexposure prophylactics, or therapeutics. Much of this can be attributed to a poor understanding of the mechanism of hantavirus disease pathogenesis. Hantavirus disease has long been considered an immune-mediated disease; however, by directly manipulating the Syrian hamster model, we continue to eliminate individual immune cell types. As the most numerous immune cells present in the respiratory tract, alveolar macrophages are

Depletion of Alveolar Macrophages Does Not Prevent Hantavirus Disease Pathogenesis in Golden Syrian Hamsters

PubMed Central

Hammerbeck, Christopher D.; Brocato, Rebecca L.; Bell, Todd M.; Schellhase, Christopher W.; Mraz, Steven R.; Queen, Laurie A.

2016-01-01

ABSTRACT Andes virus (ANDV) is associated with a lethal vascular leak syndrome in humans termed hantavirus pulmonary syndrome (HPS). The mechanism for the massive vascular leakage associated with HPS is poorly understood; however, dysregulation of components of the immune response is often suggested as a possible cause. Alveolar macrophages are found in the alveoli of the lung and represent the first line of defense to many airborne pathogens. To determine whether alveolar macrophages play a role in HPS pathogenesis, alveolar macrophages were depleted in an adult rodent model of HPS that closely resembles human HPS. Syrian hamsters were treated, intratracheally, with clodronate-encapsulated liposomes or control liposomes and were then challenged with ANDV. Treatment with clodronate-encapsulated liposomes resulted in significant reduction in alveolar macrophages, but depletion did not prevent pathogenesis or prolong disease. Depletion also did not significantly reduce the amount of virus in the lung of ANDV-infected hamsters but altered neutrophil recruitment, MIP-1α and MIP-2 chemokine expression, and vascular endothelial growth factor (VEGF) levels in hamster bronchoalveolar lavage (BAL) fluid early after intranasal challenge. These data demonstrate that alveolar macrophages may play a limited protective role early after exposure to aerosolized ANDV but do not directly contribute to hantavirus disease pathogenesis in the hamster model of HPS. IMPORTANCE Hantaviruses continue to cause disease worldwide for which there are no FDA-licensed vaccines, effective postexposure prophylactics, or therapeutics. Much of this can be attributed to a poor understanding of the mechanism of hantavirus disease pathogenesis. Hantavirus disease has long been considered an immune-mediated disease; however, by directly manipulating the Syrian hamster model, we continue to eliminate individual immune cell types. As the most numerous immune cells present in the respiratory tract

A comparative genomic hybridization approach to study gene copy number variations among Chinese hamster cell lines.

PubMed

Vishwanathan, Nandita; Bandyopadhyay, Arpan; Fu, Hsu-Yuan; Johnson, Kathryn C; Springer, Nathan M; Hu, Wei-Shou

2017-08-01

Chinese Hamster Ovary (CHO) cells are aneuploid in nature. The genome of recombinant protein producing CHO cell lines continuously undergoes changes in its structure and organization. We analyzed nine cell lines, including parental cell lines, using a comparative genomic hybridization (CGH) array focused on gene-containing regions. The comparison of CGH with copy-number estimates from sequencing data showed good correlation. Hierarchical clustering of the gene copy number variation data from CGH data revealed the lineage relationships between the cell lines. On analyzing the clones of a clonal population, some regions with altered genomic copy number status were identified indicating genomic changes during passaging. A CGH array is thus an effective tool in quantifying genomic alterations in industrial cell lines and can provide insights into the changes in the genomic structure during cell line derivation and long term culture. Biotechnol. Bioeng. 2017;114: 1903-1908. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Regional assignment of seven genes on chromosome 1 of man by use of man-Chinese hamster somatic cell hybrids. I. Results obtained after hybridization of human cells carrying reciprocal translocations involving chromosome 1.

PubMed

Jongsma, A P; Burgerhout, W G

1977-01-01

Regional localization studies of genes coding for human PGD, PPH1, PGM1, UGPP, GuK1, Pep-C, and FH, which have been assigned to chromosome 1, were performed with man-Chinese hamster somatic cell hybrids, Informative hybrids that retained fragments of the human chromosome 1 were produced by fusion of hamster cells with human cells carrying reciprocal translocations involving chromosome 1. Analysis of the hybrids that retained one of the translocation chromosomes or de novo rearrangements involving the human 1 revealed the following gene positions: PGD and PPH1 in 1pter leads to 1p32, PGM1 in 1p32 leads to 1p22, UGPP and GuK1 in 1q21 leads to 1q42, FH in 1qter leads to 1q42, and Pep-C probably in 1q42.

Secondhand smoke induces hepatic apoptosis and fibrosis in hamster fetus.

PubMed

Huang, Chien-Wei; Horng, Chi-Ting; Huang, Chih-Yang; Cho, Ta-Hsiung; Tsai, Yi-Chang; Chen, Li-Jeng; Hsu, Tsai-Ching; Tzang, Bor-Show

2016-09-01

Secondhand smoke (SHS) is an important health issue worldwide. Inhaling SHS during pregnancy could cause abnormalities in the internal tissues of newborns, which may then impair fetal development and even cause severe intrauterine damage and perinatal death. However, the understanding of cytopathic mechanisms of SHS by maternal passive smoking on fetus liver during pregnancy is still limited. This study analyzed the effects of high-dose SHS (SHSH) on fetus liver using a maternal passive smoking animal model. Experiments showed that hepatic matrix metalloproteinase-9 activity and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling-positive cells were significantly increased in livers from fetuses of hamsters treated with SHSH. Similarly, expressions of both extrinsic and intrinsic apoptotic molecules were significantly higher in livers from fetuses of hamsters exposed to SHSH. Additionally, significantly increased inflammatory proteins, including transforming growth factor β, inducible nitric oxide synthase, and interleukin 1β, and fibrotic signaling molecules, including phosphorylated Smad2/3, SP1, and α-smooth muscle actin, were observed in the fetus livers from hamsters treated with SHSH. This study revealed that SHSH not only increased apoptosis through intrinsic and extrinsic pathways in the livers of fetuses from hamsters exposed to SHSH but also augmented hepatic fibrosis via Smad2/3 signaling. © The Author(s) 2015.

Evaluation of eight cephalosporins in hamster colitis model.

PubMed Central

Ebright, J R; Fekety, R; Silva, J; Wilson, K H

1981-01-01

Eight commonly used cephalosporins were evaluated in the hamster colitis mode. They were all found to cause hemorrhagic cecitis and death within 10 days of being given as subcutaneous or oral challenges. Necropsy findings were indistinguishable from clindamycin-induced cecitis. Bacteria-free cecal filtrate obtained from hamsters dying of cephalosporin-induced cecitis contained toxin similar or identical to hat produced by Clostridium difficile isolated from the cecum of a hamster. Daily oral administration of poorly absorbed cephalosporins protected hamsters from clindamycin-induced cecitis and death as long as the cephalosporins were continued. The absorbable cephalosporins were ineffective in protecting hamsters from clindamycin-induced cecitis. This difference probably relates to the lower concentrations of absorbable cephalosporins maintained in the ceca of the hamsters. The possible correlation of these findings to human cases of cephalosporin-induced pseudomembranous colitis is discussed. PMID:6973951

THE ACTION OF α-AMANITIN ON RNA SYNTHESIS IN CHINESE HAMSTER OVARY CELLS

PubMed Central

Kedinger, Claude; Simard, Rene

1974-01-01

α-Amanitin acts in vitro as a selective inhibitor of the nucleoplasmic form B RNA polymerases. Treatment of Chinese hamster ovary (CHO) cells with this drug leads principally to a severe fragmentation of the nucleoli. While the ultrastructural lesions induced by α-amanitin in CHO cells and in rat or mouse liver are quite similar, the results diverge concerning the effect on RNA synthesis. It has been shown that in rat or mouse liver α-amanitin blocks both extranucleolar and nucleolar RNA synthesis. Our autoradiographic and biochemical evidence indicates that in CHO cells high molecular weight extranucleolar RNA synthesis (HnRNA) is blocked by the α-amanitin treatment, whereas nucleolar RNA (preribosomal RNA) synthesis remains unaffected even several hours after the inhibition of extranucleolar RNA synthesis. Furthermore, the processing of this RNA as well as its transport to the cytoplasm seem only slightly affected by the treatment. Finally, under these conditions, the synthesis of the low molecular RNA species (4–5S) still occurs, though less actively. The results are interpreted as evidence for a selective impairment of HnRNA synthesis by α-amanitin in CHO cells. PMID:4474178

Toxicological safety and stability of the components of an irradiated Korean medicinal herb, Paeoniae Radix

NASA Astrophysics Data System (ADS)

Yu, Young-Beob; Jeong, Ill-Yun; Park, Hae-Ran; Oh, Heon; Jung, Uhee; Jo, Sung-Kee

2004-09-01

As utilization of medicinal herbs in food and bio-industry increases, mass production and the supply of herbs with a high quality are required. As the use of fumigants and preservatives for herbs is being restricted, safe hygienic technologies are demanded. To consider the possibility of the application of irradiation technology for this purpose, the genotoxicological safety and stability of the active components of the γ-irradiated Paeoniae Radix were studied. The herb was irradiated with γ-rays at a practical dosage of 10 kGy, and then it was extracted with hot water. The genotoxicity of the extract of the irradiated herb was examined in two short-term in vitro tests: (1) Ames test in Salmonella typhimurium; (2) Micronucleus test in cultured Chinese hamster ovary (CHO) cells. The extract of the irradiated herb did not show mutagenicity in the Ames test of the Salmonella reverse mutation assay, and did not show cytogenetic toxicity in the culture of the CHO cells. HPLC chromatogram of paeoniflorin in the irradiated Paeoniae Radix was similar with that of the non-irradiated sample. The quantity of paeoniflorin did not change significantly with irradiation. These results suggest that γ-irradiated Paeoniae Radix is toxicologically safe and chemically stable.

In vivo but not in vitro leptin enhances lymphocyte proliferation in Siberian hamsters (Phodopus sungorus).

PubMed

Demas, Gregory E

2010-04-01

Mounting an immune response requires a relatively substantial investment of energy and marked reductions in energy availability can suppress immune function and presumably increase disease susceptibility. We have previously demonstrated that a moderate reduction in energy stores by partial surgical lipectomy impairs humoral immunity of Siberian hamsters (Phodopus sungorus) and is mediated, in part, by changes in the adipose tissue hormone leptin. The goals of the present study were to assess the role of leptin in cell-mediated immunity and to determine if the potential effects of leptin on immunity are via the direct actions of this hormone on lymphocytes, or indirect, via the sympathetic nervous system (SNS). In Experiment 1, hamsters received osmotic minipumps containing either murine leptin (0.5 microl/h) or vehicle alone for 10 days and splenocyte proliferation in response to the T-cell mitogen Concanavalin A (Con A) was determined. In Experiment 2, Con A-induced splenocyte proliferation was tested in the presence or absence of leptin in vitro. In Experiment 3, exogenous leptin was administered to intact or sympathetically denervated hamsters. Hamsters treated with in vivo leptin displayed increased splenocyte proliferation compared with control hamsters receiving vehicle. In contrast, in vitro leptin had no effect on splenocyte proliferation. Sympathetic denervation attenuated, but did not block, leptin-induced increases in immunity. Taken together, these results are consistent with the idea that leptin can enhance cell-mediated immunity; the SNS appears to contribute, least in part, to leptin-induced increases in immunity. Importantly, these findings confirm previous studies that leptin serves as an important endocrine link between energy balance and immunity. (c) 2009 Elsevier Inc. All rights reserved.

Effects of red mold dioscorea on oral carcinogenesis in DMBA-induced hamster animal model.

PubMed

Hsu, Wei-Hsuan; Lee, Bao-Hong; Pan, Tzu-Ming

2011-06-01

Monascus-fermented products offer valuable therapeutic benefits and have been extensively used for centuries in East Asia. Dioscorea has been proved to have anti-cancer effect. The aim of this study is to investigate the anti-tumor ability of the ethanol extract of red mold dioscorea (RMDE) on 7,12-dimethyl-1,2-benz[a]anthracene (DMBA)-induced hamster buccal pouch carcinogenesis. We induced oral squamous cell carcinoma (OSCC) in the buccal pouch of male Syrian golden hamsters by painting with 0.5% DMBA three times a week for 14 weeks. From 9 to 14 weeks, a dose of 50, 100, and 200 mg RMDE per kg body weight were painting with the hamsters for 6 weeks on days alternate to the DMBA application. The results demonstrated that RMDE decreased nitric oxide (NO), reactive oxygen species (ROS), and prostaglandin E(2) (PGE(2)) overexpression in hamster buccal pouches in the DMBA treatment group and increased p53, serum tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) to significantly stimulate caspase-8 and -3 activities, indicating that RMDE reduced oxidative damage causing by DMBA and induced apoptosis in oral cancer cells. Therefore, RMDE may have therapeutic potentials against OSCC. Copyright © 2011 Elsevier Ltd. All rights reserved.

[Cardiac neuronal depopulation in hamsters (Mesocricetus auratus) chronically infected with Trypanosoma cruzi].

PubMed

Chapadeiro, E; Silva, E L; Silva, A C; Fernandes, P; Ramirez, L E

1999-01-01

The aim of this study was to obtain an experimental animal model of destruction of cardiac neurons in order to investigate the behavior of the cardiac nervous system of hamsters chronically infected with Trypanosoma cruzi. We counted the neuronal cells of the cardiac autonomic nervous plexus in hamsters inoculated with 35,000 blood forms of three different T. cruzi strains and killed 5, 8 and 10 months after infection. We showed for the first time severe neuronal destruction in an experimental animal model with characteristics similar to those observed in human Chagas'disease.

Expression and activity levels of chymase in mast cells of burn wound tissues increase during the healing process in a hamster model.

PubMed

Dong, Xianglin; Xu, Tao; Ma, Shaolin; Wen, Hao

2015-06-01

The present study aimed to investigate the changes in the expression levels and activity of mast cell chymase in the process of burn wound healing in a hamster model of deep second-degree burn. The hamster model was established by exposing a ~3 cm diameter area of bare skin to hot water (75°C) for 0, 6, 8, 10 or 12 sec. Tissue specimens were collected 24 h after burning and histological analysis revealed that hot water contact for 12 sec was required to produce a deep second-degree burn. Quantitative polymerase chain reaction and a radioimmunoassay were used to the determine changes in chymase mRNA expression levels and activity. The mRNA expression levels and activity of chymase were increased in the burn wound tissues when compared with the normal skin. However, no statistically significant differences were observed in mast cell chymase activity amongst the various post-burn stages. Chymase mRNA expression levels peaked at day 1 post-burn, subsequently decreasing at days 3 and 7 post-burn and finally increasing again at day 14 post-burn. In summary, a hamster model of deep second-degree burn can be created by bringing the skin into contact with water at 75°C for 12 sec. Furthermore, the mRNA expression levels and activity of chymase in the burn wound tissues increased when compared with those in normal skin tissues.

Expression and activity levels of chymase in mast cells of burn wound tissues increase during the healing process in a hamster model

PubMed Central

DONG, XIANGLIN; XU, TAO; MA, SHAOLIN; WEN, HAO

2015-01-01

The present study aimed to investigate the changes in the expression levels and activity of mast cell chymase in the process of burn wound healing in a hamster model of deep second-degree burn. The hamster model was established by exposing a ~3 cm diameter area of bare skin to hot water (75°C) for 0, 6, 8, 10 or 12 sec. Tissue specimens were collected 24 h after burning and histological analysis revealed that hot water contact for 12 sec was required to produce a deep second-degree burn. Quantitative polymerase chain reaction and a radioimmunoassay were used to the determine changes in chymase mRNA expression levels and activity. The mRNA expression levels and activity of chymase were increased in the burn wound tissues when compared with the normal skin. However, no statistically significant differences were observed in mast cell chymase activity amongst the various post-burn stages. Chymase mRNA expression levels peaked at day 1 post-burn, subsequently decreasing at days 3 and 7 post-burn and finally increasing again at day 14 post-burn. In summary, a hamster model of deep second-degree burn can be created by bringing the skin into contact with water at 75°C for 12 sec. Furthermore, the mRNA expression levels and activity of chymase in the burn wound tissues increased when compared with those in normal skin tissues. PMID:26136958

Damage and Repair of DNA in 5-Bromodeoxyuridine-Labeled Chinese Hamster Cells Exposed to Fluorescent Light

PubMed Central

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

1972-01-01

Illumination of Chinese hamster cells with fluorescent light after 5-bromodeoxyuridine incorporation leads to extensive single-strand breakage in the DNA of the exposed cells. The rate of production of single-strand breaks is dependent on the extent to which thymine is replaced by 5-bromouracil. At least some of the breaks observed with alkaline gradients are probably produced in vivo and are probably not contingent upon alkaline hydrolysis since breakage can be demonstrated with neutral gradients also. Cells are able to rejoin most of the single-strand breaks within 60 min; however, damage to the DNA-containing material (the “complex”) initially released from cells is repaired more slowly. Cysteamine protects against single-strand breakage with a dose-modifying factor of 2.8. A comparison is made between the production of single-strand breaks by fluorescent light and X-rays, and the significance of such breaks relative to cell survival is discussed. PMID:5063839

Characterization of prmt7alpha and beta isozymes from Chinese hamster cells sensitive and resistant to topoisomerase II inhibitors.

PubMed

Gros, Laurent; Renodon-Cornière, Axelle; de Saint Vincent, Bruno Robert; Feder, Marcin; Bujnicki, Janusz M; Jacquemin-Sablon, Alain

2006-11-01

By selection of genetic suppressor elements (GSEs) conferring resistance to topoisomerase II inhibitors in Chinese hamster cells (DC-3F), we identified a gene encoding two proteins of 78 and 82 kDa which belong to the protein arginine methyltransferase (PRMT) family. Down-regulation of these enzymes (named PRMT7alpha and beta), either induced by an antisense GSE or as observed in the 9-OH-ellipticine (9-OH-E) resistant mutant DC-3F/9-OH-E, was responsible for cell resistance to various DNA damaging agents. Alternative splicing alterations in the 5'-terminal region and changes of the polyadenylation site of PRMT7 mRNAs were observed in these resistant mutant cells. PRMT7alpha and beta are isoforms of a highly conserved protein containing two copies of a module common to all PRMTs, comprising a Rossmann-fold domain and a beta-barrel domain. The C-terminal repeat appears to be degenerate and catalytically inactive. PRMT7alpha and beta form homo- and hetero-dimers but differ by their sub-cellular localization and in vitro recognize different substrates. PRMT7beta was only observed in Chinese hamster cells while mouse 10T1/2 fibroblasts only contain PRMT7alpha. Surprisingly, in human cells the anti-PRMT7 antibody essentially recognized an approximately 37 kDa peptide, which is not formed during extraction, and a faint band at 78 kDa. Analysis of in vitro and in vivo methylation patterns in cell lines under- or over-expressing PRMT7alpha and beta detected a discrete number of proteins which methylation and/or expression are under the control of these enzymes.

Induction of tissue transglutaminase by dexamethasone: its correlation to receptor number and transglutaminase-mediated cell death in a series of malignant hamster fibrosarcomas.

PubMed Central

Johnson, T S; Scholfield, C I; Parry, J; Griffin, M

1998-01-01

Treatment of the hamster fibrosarcoma cell lines (Met B, D and E) and BHK-21 hamster fibroblast cells with the glucocorticoid dexamethasone led to a powerful dose-dependent mRNA-synthesis-dependent increase in transglutaminase activity, which can be correlated with dexamethasone-responsive receptor numbers in each cell line. Increasing the number of dexamethasone-responsive receptors by transfection of cells with the HG1 glucocorticoid receptor protein caused an increase in transglutaminase activity that was proportional to the level of transfected receptor. In all experiments the levels of the tissue transglutaminase-mediated detergent-insoluble bodies was found to be comparable with increases in transglutaminase activity. Despite an increase in detergent-insoluble body formation, an increase in apoptosis as measured by DNA fragmentation was not found. Incubation of cells with the non-toxic competitive transglutaminase substrate fluorescein cadaverine led to the incorporation of this fluorescent amine into cellular proteins when cells were damaged after exposure to trypsin during cell passage. These cross-linked proteins containing fluorescein cadaverine were shown to be present in the detergent-insoluble bodies, indicating that the origin of these bodies is via activation of tissue transglutaminase after cell damage by trypsinization rather than apoptosis per se, since Met B cells expressing the bcl-2 cDNA were not protected from detergent-insoluble body formation. We describe a novel mechanism of cell death related to tissue transglutaminase expression and cell damage. PMID:9512467

Metabolic engineering of Chinese hamster ovary cells: Towards a bioengineered heparin

PubMed Central

Baik, Jong Youn; Gasimli, Leyla; Yang, Bo; Datta, Payel; Zhang, Fuming; Glass, Charles A.; Esko, Jeffrey D.; Linhardt, Robert J.; Sharfstein, Susan T.

2012-01-01

Heparin is the most widely used pharmaceutical to control blood coagulation in modern medicine. A health crisis that took place in 2008 led to a demand for production of heparin from non-animal sources. Chinese hamster ovary (CHO) cells, commonly used mammalian host cells for production of foreign pharmaceutical proteins in the biopharmaceutical industry, are capable of producing heparan sulfate (HS), a related polysaccharide naturally. Since heparin and HS share the same biosynthetic pathway, we hypothesized that heparin could be produced in CHO cells by metabolic engineering. Based on the expression of endogenous enzymes in the HS / heparin pathways of CHO-S cells, human N-deacetylase/N-sulfotransferase (NDST2) and mouse heparan sulfate 3-O-sulfotransferase 1 (Hs3st1) genes were transfected sequentially into CHO host cells growing in suspension culture. Transfectants were screened using quantitative RT-PCR and Western blotting. Out of 120 clones expressing NDST2 and Hs3st1, 2 clones, Dual-3 and Dual-29, were selected for further analysis. An antithrombin III (ATIII) binding assay using flow cytometry, designed to recognize a key sugar structure characteristic of heparin, indicated that Hs3st1 transfection was capable of increasing ATIII binding. An anti-factor Xa assay, which affords a measure of anticoagulant activity, showed a significant increase in activity in the dual-expressing cell lines. Disaccharide analysis of the engineered HS showed a substantial increase in N-sulfo groups, but did not show a pattern consistent with pharmacological heparin, suggesting that further balancing the expression of transgenes with the expression levels of endogenous enzymes involved in HS / heparin biosynthesis might be necessary. PMID:22326251

Metabolic engineering of Chinese hamster ovary cells: towards a bioengineered heparin.

PubMed

Baik, Jong Youn; Gasimli, Leyla; Yang, Bo; Datta, Payel; Zhang, Fuming; Glass, Charles A; Esko, Jeffrey D; Linhardt, Robert J; Sharfstein, Susan T

2012-03-01

Heparin is the most widely used pharmaceutical to control blood coagulation in modern medicine. A health crisis that took place in 2008 led to a demand for production of heparin from non-animal sources. Chinese hamster ovary (CHO) cells, commonly used mammalian host cells for production of foreign pharmaceutical proteins in the biopharmaceutical industry, are capable of producing heparan sulfate (HS), a related polysaccharide naturally. Since heparin and HS share the same biosynthetic pathway, we hypothesized that heparin could be produced in CHO cells by metabolic engineering. Based on the expression of endogenous enzymes in the HS/heparin pathways of CHO-S cells, human N-deacetylase/N-sulfotransferase (NDST2) and mouse heparan sulfate 3-O-sulfotransferase 1 (Hs3st1) genes were transfected sequentially into CHO host cells growing in suspension culture. Transfectants were screened using quantitative RT-PCR and Western blotting. Out of 120 clones expressing NDST2 and Hs3st1, 2 clones, Dual-3 and Dual-29, were selected for further analysis. An antithrombin III (ATIII) binding assay using flow cytometry, designed to recognize a key sugar structure characteristic of heparin, indicated that Hs3st1 transfection was capable of increasing ATIII binding. An anti-factor Xa assay, which affords a measure of anticoagulant activity, showed a significant increase in activity in the dual-expressing cell lines. Disaccharide analysis of the engineered HS showed a substantial increase in N-sulfo groups, but did not show a pattern consistent with pharmacological heparin, suggesting that further balancing the expression of transgenes with the expression levels of endogenous enzymes involved in HS/heparin biosynthesis might be necessary. Copyright © 2012 Elsevier Inc. All rights reserved.

Histiocytic Sarcoma and Bilateral Facial Vein Thrombosis in a Siberian Hamster (Phodopus sungorus).

PubMed

Coble, Dondrae J; Shoemaker, Margaret; Harrington, Bonnie; Dardenne, Adrienne D; Bolon, Brad

2015-04-01

A 21-mo-old, male Siberian hamster (Phodopus sungorus) presented with left-sided facial swelling, proptosis of the left eye, and blepharospasm of the right eye. The hamster had been used only for breeding. Because of the poor prognosis, the hamster was euthanized without additional diagnostic assays or treatments. Routine gross pathologic evaluation demonstrated exophthalmos and presumptive hyphema of the left eye, bilateral facial edema, freely movable nodules within the mesentery, white foci within the liver, and a large mass effacing the cranial pole of the right kidney. On histologic evaluation, the mesenteric nodules and liver foci expressed histiocytic marker CD163 and thus were diagnosed as sites of histiocytic sarcoma, whereas the kidney mass was a well-differentiated renal cell carcinoma. The facial swelling resulted from bilateral, chronic, severe, branching thrombi in many facial veins. Additional age-related histopathologic findings were observed in other organs, including diffuse glomerulopathy, nesidioblastosis (pancreatic islet neoformation), and multiple foci of severe cartilage degeneration in the axial skeleton. To our knowledge, this report provides the first description of histiocytic sarcoma in a Siberian hamster.

Laguna Negra Virus Infection Causes Hantavirus Pulmonary Syndrome in Turkish Hamsters (Mesocricetus brandti).

PubMed

Hardcastle, K; Scott, D; Safronetz, D; Brining, D L; Ebihara, H; Feldmann, H; LaCasse, R A

2016-01-01

Laguna Negra virus (LNV) is a New World hantavirus associated with severe and often fatal cardiopulmonary disease in humans, known as hantavirus pulmonary syndrome (HPS). Five hamster species were evaluated for clinical and serologic responses following inoculation with 4 hantaviruses. Of the 5 hamster species, only Turkish hamsters infected with LNV demonstrated signs consistent with HPS and a fatality rate of 43%. Clinical manifestations in infected animals that succumbed to disease included severe and rapid onset of dyspnea, weight loss, leukopenia, and reduced thrombocyte numbers as compared to uninfected controls. Histopathologic examination revealed lung lesions that resemble the hallmarks of HPS in humans, including interstitial pneumonia and pulmonary edema, as well as generalized infection of endothelial cells and macrophages in major organ tissues. Histologic lesions corresponded to the presence of viral antigen in affected tissues. To date, there have been no small animal models available to study LNV infection and pathogenesis. The Turkish hamster model of LNV infection may be important in the study of LNV-induced HPS pathogenesis and development of disease treatment and prevention strategies. © The Author(s) 2015.

Mutagenic activities of heterocyclic amines in Chinese hamster lung cells in culture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terada, M.; Nagao, M.; Nakayasu, M.

1986-01-01

A mutation assay system with Chinese hamster lung cells (CHL) using diphtheria toxin resistance as a selective marker has been established. The mutagenic activities of heterocyclic amines, originally isolated from pyrolyzates of amino acids and proteins, broiled fish and fried beef were assayed in cultured CHL cells in the absence and presence of a metabolic activation system, with diphtheria toxin resistance as a marker. All the heterocyclic amines tested except 3-amino-1,4-dimethyl-5H-pyrido (4,3-b)indole (Trp-P-1) required the presence of a metabolic activation system for mutagenicity on CHL cells. 3-Amino-1-methyl-5H-pyrido(4,3-b)indole (Trp-P-2) was the most mutagenic among the heterocyclic amines tested. Other compounds weremore » also mutagenic in the following order of decreasing potency: Trp-P-1, 2-amino-3,4-dimethylimidazo(4,5-f)quinoline (MeIQ), 2-amino-3-methylimidazo(4,5-f)quinoline (IQ), 2-amino-9H-pyrido(2,3-b)indole (A..cap alpha..C), 2-amino-3,8-dimethylimidazo(4,5-f)quinoxaline (MeIQx), 2-amino-6-methyldipyrido(1,2-a:3',2'-d)imidazole (Glu-P-1) and 2-aminodipyrido(1,2--a:3',2'-d)imidazole (Glu-P-2).« less

Heat-resistant variants of the Chinese hamster ovary cell: alteration of cellular structure and expression of vimentin.

PubMed

Lee, Y J; Hou, Z Z; Curetty, L; Armour, E P; al-Saadi, A; Bernstein, J; Corry, P M

1992-04-01

Three heat-resistant mutant cell lines (78-1, 78-2, 78-3) were previously selected from Chinese hamster ovary cells. In this study, we investigated whether the differences in intrinsic thermal sensitivity result from alteration of stress protein levels or cellular structural changes. Although there was no significant difference in the levels of stress proteins, i.e., constitutive HSP70 in wild type and three heat-resistant mutant strains, there were marked differences in the amounts of vimentin among the cell lines. Two-dimensional gel electrophoresis and Western blot showed a 2.3-2.9-fold increase in the level of vimentin in the mutant cells under normal growth conditions. Northern blot also revealed higher amounts of vimentin mRNA in the mutant cells. Electron microscopy and immunofluorescence suggest that increased amounts of the vimentin-containing intermediate filaments are correlated with the heat-resistant phenotypes.

Stable expression of rat cytochrome P-450IIB1 cDNA in Chinese hamster cells (V79) and metabolic activation of aflatoxin B1.

PubMed Central

Doehmer, J; Dogra, S; Friedberg, T; Monier, S; Adesnik, M; Glatt, H; Oesch, F

1988-01-01

V79 Chinese hamster fibroblasts are widely used for mutagenicity testing but have the serious limitation that they do not express cytochromes P-450, which are needed for the activation of many promutagens to mutagenic metabolites. A full-length cDNA clone encoding the monooxygenase cytochrome P-450IIB1 under control of the simian virus 40 early promoter was constructed and cointroduced with the selection marker neomycin phosphotransferase (conferring resistance to G418) into V79 Chinese hamster cells. G418-resistant cells were selected, established as cell lines, and tested for cytochrome P-450IIB1 expression and enzymatic activity. Two cell lines (SD1 and SD3) were found that stably produce cytochrome P-450IIB1. Although purified cytochromes P-450 possess monooxygenase activity only after reconstitution with cytochrome P-450 reductase and phospholipid, the gene product of the construct exhibited this activity. This implies that the gene product is intracellularly localized in a way that allows access to the required components. If compared with V79 cells, the mutation rate for the hypoxanthine phosphoribosyltransferase (HPRT) locus in SD1 cells is markedly increased when exposed to aflatoxin B1, which is activated by this enzyme. Images PMID:3137560

Post-irradiation-examination of irradiated fuel outside the hot cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dawn E. Janney; Adam B. Robinson; Thomas P. O'Holleran

Because of their high radioactivity, irradiated fuels are commonly examined in a hot cell. However, the Idaho National Laboratory (INL) has recently investigated irradiated U-Mo-Al metallic fuel from the Reduced Enrichment for Research and Test Reactors (RERTR) project using a conventional unshielded scanning electron microscope outside a hot cell. This examination was possible because of a two-step sample-preparation approach in which a small volume of fuel was isolated in a hot cell and shielding was introduced during later stages of sample preparation. The resulting sample contained numerous sample-preparation artifacts but allowed analysis of microstructures from selected areas.

Cultivation of recombinant Chinese hamster ovary cells grown as suspended aggregates in stirred vessels.

PubMed

Han, Yi; Liu, Xing-Mao; Liu, Hong; Li, Shi-Chong; Wu, Ben-Chuan; Ye, Ling-Ling; Wang, Qu-Wei; Chen, Zhao-Lie

2006-11-01

Recombinant Chinese hamster ovary (rCHO) cells capable of producing a prourokinase mutant (mPro-uk) grown as suspended aggregates in stirred vessels were described and characterized. The addition of chitosan to a mixture of DMEM and Ham's F12 (D-MEM/F-12) medium promoted cell aggregation and spheroid formation efficiently. Multicellular aggregates formed immediately after the rCHO cells were inoculated into the chitosan-added medium, and the mean diameter of the cell aggregates reflecting the aggregate size increased with culture time, shifting from 65 to 163 mum after 2 and 9 d of culture in spinner flasks. No significant difference in the metabolism performance of the rCHO cells was observed between suspended aggregates and anchored monolayers. However, the cells cultured as suspended aggregates showed a marked decrease in growth rate as evaluated from specific growth rate (mu). Replacing D-MEM/F-12 medium with CD 293 medium caused compact spherical cell aggregates to dissociate into small irregular aggregates and single cells without apparent effects on cell performance in subcultures. The perfusion culture of the rCHO cells grown as suspended aggregates in a 2-l stirred tank bioreactor for 15 d resulted in a maximum viable cell density of 5.6 x 10(6) cells ml(-1) and an mPro-uk concentration of about 2.6 x 10(3) IU ml(-1), and cell viability was remained at roughly 90% during the entire run.

Neurogenesis and ontogeny of specific cell phenotypes within the hamster suprachiasmatic nucleus.

PubMed

Antle, Michael C; LeSauter, Joseph; Silver, Rae

2005-06-09

The hamster suprachiasmatic nucleus (SCN) is anatomically and functionally heterogeneous. A group of cells in the SCN shell, delineated by vasopressin-ergic neurons, are rhythmic with respect to Period gene expression and electrical activity but do not receive direct retinal input. In contrast, some cells in the SCN core, marked by neurons containing calbindin-D28k, gastrin-releasing peptide (GRP), substance P (SP), and vasoactive intestinal polypeptide (VIP), are not rhythmic with respect to Period gene expression and electrical activity but do receive direct retinal input. Examination of the timing of neurogenesis using bromodeoxyuridine indicates that SCN cells are born between embryonic day 9.5 and 12.5. Calbindin, GRP, substance P, and VIP cells are born only during early SCN neurogenesis, between embryonic days 9.5-11.0. Vasopressin cells are born over the whole period of SCN neurogenesis, appearing as late as embryonic day 12.5. Examination of the ontogeny of peptide expression in these cell types reveals transient expression of calbindin in a cluster of dorsolateral SCN cells on postnatal days 1-2. The adult pattern of calbindin expression is detected in a different ventrolateral cell cluster starting on postnatal day 2. GRP and SP expression appear on postnatal day 8 and 10, respectively, after the retinohypothalamic tract has innervated the SCN. In summary, the present study describes the ontogeny-specific peptidergic phenotypes in the SCN and compares these developmental patterns to previously identified patterns in the appearance of circadian functions. These comparisons suggest the possibility that these coincident appearances may be causally related, with the direction of causation to be determined.

X-ray irradiation of yeast cells

NASA Astrophysics Data System (ADS)

Masini, Alessandra; Batani, Dimitri; Previdi, Fabio; Conti, Aldo; Pisani, Francesca; Botto, Cesare; Bortolotto, Fulvia; Torsiello, Flavia; Turcu, I. C. Edmond; Allott, Ric M.; Lisi, Nicola; Milani, Marziale; Costato, Michele; Pozzi, Achille; Koenig, Michel

1997-10-01

Saccharomyces Cerevisiae yeast cells were irradiated using the soft X-ray laser-plasma source at Rutherford Laboratory. The aim was to produce a selective damage of enzyme metabolic activity at the wall and membrane level (responsible for fermentation) without interfering with respiration (taking place in mitochondria) and with nuclear and DNA activity. The source was calibrated by PIN diodes and X-ray spectrometers. Teflon stripes were chosen as targets for the UV laser, emitting X-rays at about 0.9 keV, characterized by a very large decay exponent in biological matter. X-ray doses to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. After irradiation, the selective damage to metabolic activity at the membrane level was measured by monitoring CO2 production with pressure silicon detectors. Preliminary results gave evidence of pressure reduction for irradiated samples and non-linear response to doses. Also metabolic oscillations were evidenced in cell suspensions and it was shown that X-ray irradiation changed the oscillation frequency.

Selenite restores Pax6 expression in neuronal cells of chronically arsenic-exposed Golden Syrian hamsters.

PubMed

Aguirre-Vázquez, Alain; Sampayo-Reyes, Adriana; González-Escalante, Laura; Hernández, Alba; Marcos, Ricard; Castorena-Torres, Fabiola; Lozano-Garza, Gerardo; Taméz-Guerra, Reyes; de León, Mario Bermúdez

2017-01-01

Arsenic is a worldwide environmental pollutant that generates public health concerns. Various types of cancers and other diseases, including neurological disorders, have been associated with human consumption of arsenic in drinking water. At the molecular level, arsenic and its metabolites have the capacity to provoke genome instability, causing altered expression of genes. One such target of arsenic is the Pax6 gene that encodes a transcription factor in neuronal cells. The aim of this study was to evaluate the effect of two antioxidants, α-tocopheryl succinate (α-TOS) and sodium selenite, on Pax6 gene expression levels in the forebrain and cerebellum of Golden Syrian hamsters chronically exposed to arsenic in drinking water. Animals were divided into six groups. Using quantitative real-time reverse transcriptase (RT)-PCR analysis, we confirmed that arsenic downregulates Pax6 expression in nervous tissues by 53 ± 21% and 32 ± 7% in the forebrain and cerebellum, respectively. In the presence of arsenic, treatment with α-TOS did not modify Pax6 expression in nervous tissues; however, sodium selenite completely restored Pax6 expression in the arsenic-exposed hamster forebrain, but not the cerebellum. Although our results suggest the use of selenite to restore the expression of a neuronal gene in arsenic-exposed animals, its use and efficacy in the human population require further studies.

Circadian rhythms accelerate wound healing in female Siberian hamsters

PubMed Central

Cable, Erin J.; Onishi, Kenneth G.; Prendergast, Brian J.

2017-01-01

Circadian rhythms (CRs) provide temporal regulation and coordination of numerous physiological traits, including immune function. CRs in multiple aspects of immune function are absent in rodents that have been rendered circadian-arrhythmic through various methods. In Siberian hamsters, circadian arrhythmia can be induced by disruptive light treatments (DPS). Here we examined CRs in wound healing, and the effects of circadian disruption on wound healing in DPS-arrhythmic hamsters. Circadian entrained/rhythmic (RHYTH) and behaviorally-arrhythmic (ARR) female hamsters were administered a cutaneous wound either 3 h after light onset (ZT03) or 2 h after dark onset (ZT18); wound size was quantified daily using image analyses. Among RHYTH hamsters, ZT03 wounds healed faster than ZT18 wounds, whereas in ARR hamsters, circadian phase did not affect wound healing. In addition, wounds healed slower in ARR hamsters. The results document a clear CR in wound healing, and indicate that the mere presence of organismal circadian organization enhances this aspect of immune function. Faster wound healing in CR-competent hamsters may be mediated by CR-driven coordination of the temporal order of mechanisms (inflammation, leukocyte trafficking, tissue remodeling) underlying cutaneous wound healing. PMID:27998755

Heterogeneity within populations of recombinant Chinese hamster ovary cells expressing human interferon-gamma.

PubMed

Coppen, S R; Newsam, R; Bull, A T; Baines, A J

1995-04-20

The Chinese hamster ovary (CHO) cell line has great commercial importance in the production of recombinant human proteins, especially those for therapeutic use. Much attention has been paid to CHO cell population physiology in order to define factors affecting product fidelity and yield. Such studies have revealed that recombinant proteins, including human interferon-gamma (IFN-gamma), can be heterogeneous both in glycosylation and in proteolytic processing. The type of heterogeneity observed depends on the growth physiology of the cell population, although the relationship between them is complex. In this article we report results of a cytological study of the CHO320 line which expresses recombinant human IFN-gamma. When grown in suspension culture, this cell line exhibited three types of heterogeneity: (1) heterogeneity of the production of IFN-gamma within the cell population, (2) heterogeneity of the number of nuclei and mitotic spindles in dividing cells, and (3) heterogeneity of cellular environment. The last of these arises from cell aggregates which form in suspension culture: Some cells are exposed to the culture medium; others are fully enclosed within the mass with little or no direct access to the medium. Thus, live cells producing IFN-gamma are heterogeneous in their environment, with variable access to O(2) and nutrients. Within the aggregates, it appears that live cells proliferate on a dead cell mass. The layer of live cells can be several cells deep. Specific cell-cell attachments are observed between the living cells in these aggregates. Two proteins, known to be required for the formation of certain types of intercellular junctions, spectrin and vinculin, have been localized to the regions of cell-cell contact. The aggregation of the cells appears to be an active process requiring protein synthesis. (c) 1995 John Wiley & Sons, Inc.

V79 Chinese-hamster cells rendered resistant to high cadmium concentration also become resistant to oxidative stress.

PubMed Central

Mello-Filho, A C; Chubatsu, L S; Meneghini, R

1988-01-01

Chinese hamster cells (V79) resistant to high concentrations of Cd2+ in the medium were obtained by using the procedure of Beach & Palmiter [(1981) Proc. Natl. Acad. Sci. U.S.A. 78, 2110-2114], which in mouse led to amplification of metallothionein (MT) genes and to an enrichment in cellular MT. The Cd-resistant V79 clones isolated were significantly more resistant than parental cells to oxidative stress by extracellular H2O2 or a mixture of H2O2 and superoxide anion (O2-) generated by xanthine oxidase plus acetaldehyde. On a per-cell basis, there was no difference between the two cells in their total H2O2-decomposing or O2-(-)dismutating activity. The most likely explanation is that an enrichment in MT content in the Cd-resistant cells was responsible for this effect, because of the antioxidant properties already described for this protein. Images Fig. 2. PMID:2851992

EMODIN EFFICACY ON THE AKT, MAPK, ERK AND DNMT EXPRESSION PATTERN DURING DMBA-INDUCED ORAL CARCINOMA IN GOLDEN SYRIAN HAMSTERS.

PubMed

Manimaran, Asokan; Manoharan, Shanmugam; Neelakandan, Mani

2016-01-01

The present study has evaluated the Emodin efficacy on the Akt, MAPK, ERK and DNMT expression pattern during 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinoma in golden Syrian hamsters, in order to explore its antitumor potential. Oral tumors were developed in the buccal pouches of golden Syrian hamsters using the carcinogen, DMBA. While the incidence of tumor formation was 100% in hamsters treated with DMBA alone, the tumor formation was not noticed in DMBA+ Emodin treated hamsters. Also, Emodin reduced the severity of precancerous pathological lesions such as dysplasia, in the hamsters treated with DMBA. Emodin administration corrected the abnormalities in the expression pattern of Akt, MAPK, ERK and DNMT in the buccal mucosa of hamsters treated with DMBA. The present study thus suggests that the tumor preventive potential of Emodin is partly related to its modulating effect on the Akt, MAPK, ERK and DNMT expression pattern, as these molecular markers have a pivotal role in the process of cell proliferation, inflammation, invasion, and apoptosis.

Topical Olive Leaf Extract Improves Healing of Oral Mucositis in Golden Hamsters.

PubMed

Showraki, Najmeh; Mardani, Maryam; Emamghoreishi, Masoumeh; Andishe-Tadbir, Azadeh; Aram, Alireza; Mehriar, Peiman; Omidi, Mahmoud; Sepehrimanesh, Masood; Koohi-Hosseinabadi, Omid; Tanideh, Nader

2016-12-01

Oral mucositis (OM) is a common side effect of anti-cancer drugs and needs significant attention for its prevention. This study aimed to evaluate the healing effects of olive leaf extract on 5-fluorouracil-induced OM in golden hamster. OM was induced in 63 male golden hamsters by the combination of 5-fluorouracil injections (days 0, 5 and 10) and the abrasion of the cheek pouch (days 3 and 4). On day 12, hamsters were received topical olive leaf extract ointment, base of ointment, or no treatment (control) for 5 days. Histopathology evaluations, blood examinations, and tissue malondialdehyde level measurement were performed 1, 3 and 5 days after treatments. Histopathology score and tissue malondialdehyde level were significantly lower in olive leaf extract treated group in comparison with control and base groups ( p = 0.000). Significant decreases in white blood cell, hemoglobin, hematocrit , and mean corpuscular volume and an increase in mean corpuscular hemoglobin concentration were observed in olive leaf extract treated group in comparison with control and base groups ( p < 0.05). Our findings demonstrated that daily application of olive leaf extract ointment had healing effect on 5-fluorouracil induced OM in hamsters. Moreover, the beneficial effect of olive leaf extract on OM might be due to its antioxidant and anti-inflammatory properties.

A mechanistic study on the effect of dexamethasone in moderating cell death in Chinese Hamster Ovary cell cultures.

PubMed

Jing, Ying; Qian, Yueming; Ghandi, Mahmoud; He, Aiqing; Borys, Michael C; Pan, Shih-Hsie; Li, Zheng Jian

2012-01-01

Dexamethasone (DEX) was previously shown (Jing et al., Biotechnol Bioeng. 2010;107:488-496) to play a dual role in increasing sialylation of recombinant glycoproteins produced by Chinese Hamster Ovary (CHO) cells. DEX addition increased sialic acid levels of a recombinant fusion protein through increased expression of α2,3-sialyltransferase and β1,4-galactosyltransferase, but also decreased the sialidase-mediated, extracellular degradation of sialic acid through slowing cell death at the end of the culture period. This study examines the underlying mechanism for this cytoprotective action by studying the transcriptional response of the CHO cell genome upon DEX treatment using DNA microarrays and gene ontology term analysis. Many of those genes showing a significant transcriptional response were associated with the regulation of programmed cell death. The gene with the highest change in expression level, as validated by Quantitative PCR assays with TaqMan® probes and confirmed by Western Blot analysis, was the antiapoptotic gene Tsc22d3, also referred to as GILZ (glucocorticoid-induced leucine zipper). The pathway by which DEX suppressed cell death towards the end of the culture period was also confirmed by showing involvement of glucocorticoid receptors and GILZ through studies using the glucocorticoid antagonist mifepristone (RU-486). These findings advance the understanding of the mechanism by which DEX suppresses cell death in CHO cells and provide a rationale for the application of glucocorticoids in CHO cell culture processes. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

neu mutation in schwannomas induced transplacentally in Syrian golden hamsters by N-nitrosoethylurea: high incidence but low allelic representation.

PubMed

Buzard, G S; Enomoto, T; Hongyo, T; Perantoni, A O; Diwan, B A; Devor, D E; Reed, C D; Dove, L F; Rice, J M

1999-10-01

Peripheral nerve tumors (PNT) and melanomas induced transplacentally on day 14 of gestation in Syrian golden hamsters by N-nitrosoethylurea were analyzed for activated oncogenes by the NIH 3T3 transfection assay, and for mutations in the neu oncogene by direct sequencing, allele-specific oligonucleotide hybridization, MnlI restriction-fragment-length polymorphism, single-strand conformation polymorphism, and mismatch amplification mutation assays. All (67/67) of the PNT, but none of the melanomas, contained a somatic missense T --> A transversion within the neu oncogene transmembrane domain at a site corresponding to that which also occurs in rat schwannomas transplacentally induced by N-nitrosoethylurea. In only 2 of the 67 individual hamster PNT did the majority of tumor cells appear to carry the mutant neu allele, in contrast to comparable rat schwannomas in which it overwhelmingly predominates. The low fraction of hamster tumor cells carrying the mutation was stable through multiple transplantation passages. In the hamster, as in the rat, specific point-mutational activation of the neu oncogene thus constitutes the major pathway for induction of PNT by transplacental exposure to an alkylating agent, but the low allelic representation of mutant neu in hamster PNT suggests a significant difference in mechanism by which the mutant oncogene acts in this species.

Homologous Recombination Repair Protects Against Particulate Chromate-induced Chromosome Instability in Chinese Hamster Cells

PubMed Central

Stackpole, Megan M.; Wise, Sandra S.; Duzevik, Eliza Grlickova; Munroe, Ray C.; Thompson, W. Douglas; Thacker, John; Thompson, Larry H.; Hinz, John M.; Wise, John Pierce

2008-01-01

Particulate hexavalent chromium [Cr(VI)] compounds are well-established human carcinogens. Cr(VI)-induced tumors are characterized by chromosomal instability (CIN); however, the mechanisms of this effect are unknown. We investigated the hypothesis that homologous recombination (HR) repair of DNA double strand breaks protect cells from Cr(VI)-induced CIN by focusing on the XRCC3 and RAD51C genes, which play an important role in cellular resistance to DNA double strand breaks. We used Chinese hamster cells defective in each HR gene (irs3 for RAD51C and irs1SF for XRCC3) and compared with their wildtype parental and cDNA-complemented controls. We found that the intracellular Cr ion levels varied among the cell lines after particulate chromate treatment. Importantly, accounting for differences in Cr ion levels, we discovered that XRCC3 and RAD51C cells treated with lead chromate had increased cytotoxicity and chromosomal aberrations, relative to wild-type and cDNA-complimented cells. We also observed the emergence of high levels of chromatid exchanges in the two mutant cell lines. For example, 1 ug/cm2 lead chromate induced 20 and 32 exchanges in XRCC3- and RAD51C-deficient cells, respectively, whereas no exchanges were detected in the wildtype and cDNA-complemented cells. These observations suggest that HR protects cells from Cr(VI)-induced CIN, consistent with the ability of particulate Cr(VI) to induce double strand breaks. PMID:17662313

Induction of carcinomas and sarcomas by 9,10-dimethyl-1,2-benzanthracene administration into the hamster maxillary sinus.

PubMed

Yura, Y; Tsujimoto, H; Kusaka, J; Harada, K; Yoshida, H; Sato, M

1995-03-01

To determine whether the local administration of 9,10-dimethyl-1,2-benzanthracene (DMBA) into the hamster maxillary sinus induced carcinoma at the injected site, hamsters were injected with 30 microliters of 0.5% solution of DMBA in dimethyl sulfoxide (DMSO) through the infraorbital foramen into the maxillary sinus once weekly for 10 weeks (Group 2). Another group of hamsters (Group 1) received similar injections of 30 microliters of DMSO only. In a third group of animals (Group 3), a roll of oxycellulose was inserted into the maxillary sinus and 40 microliters of a 2% solution of DMBA in DMSO was injected once. Sinonasal carcinomas were demonstrated in 73% (8/11) of the hamsters in Group 2 and sarcomas were shown in 73% (8/11) of the hamsters in Group 3, as well as some carcinomas. No tumors were seen in the Group 1 hamsters. Histologic examination revealed squamous cell carcinomas arising from the surface epithelium and submucous glands of the nasal cavity and maxillary sinus. These findings indicate that the intrasinal administration of a 0.5% solution of DMBA in DMSO is a reliable method for inducing maxillary sinus cancer.

Chemoprevention by Quercetin of Oral Squamous Cell Carcinoma by Suppression of the NF-κB Signaling Pathway in DMBA-treated Hamsters.

PubMed

Zhang, Wen; Yin, Gang; Dai, Jianguo; Sun, Y U; Hoffman, Robert M; Yang, Zhijian; Fan, Yuan

2017-08-01

The aim of this study was to investigate the effects of the flavonoid quercetin on chemoprevention of oral squamous cell carcinoma (OSCC). The study involved molecular signaling pathways in 7,12-dimethylbenz(a) anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. DMBA (0.5%) was painted at the right buccal pouches of hamsters for 14 weeks to induce carcinoma. DMBA-treated hamsters received simultaneous doses of quercetin. Animals without DMBA induction were used as normal controls. The incidence of OSCC and the severity of pre-malignant lesions were determined histologically. Apoptosis in the pouch tissue was determined by TUNEL staining. The mRNA and protein expression of NF-κB p50 and p65, as well as Bcl-2 and Bax genes were analyzed using RT-PCR and Western blotting, respectively. Quercetin, at various doses, significantly reduced OSCC incidence and severity of hyperplasia and dysplasia compared to the DMBA-induction-only group (p<0.01). Apoptosis was induced by quercetin treatment compared to the DMBA-induction-only group (p<0.01). mRNA and protein expression of NF-κB p50, p65 as well as Bcl-2 genes were significantly suppressed by quercetin at high doses compared to DMBA induction only (p<0.05). However, mRNA and protein expression of the Bax gene was increased by quercetin treatment at medium and high doses, compared to the DMBA-induction-only group (p<0.05). Quercetin significantly reduced body-weight loss compared to the DMBA-induction-only group (p<0.05). Quercetin reduced tumor incidence and induced apoptosis through modulation of NF-κB signaling and its target genes Bcl-2 and Bax in the DMBA-induced carcigenesis hamster model, suggesting the potential of quercetin as a candidate for OSCC chemoprevention. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Mitochondrial function in diaphragm of emphysematous hamsters after treatment with nandrolone.

PubMed

Wijnhoven, Hanneke J H; Ennen, Leo; Rodenburg, Richard J T; Dekhuijzen, P N Richard

2006-01-01

Respiratory failure in patients with COPD may be caused by insufficient force production or insufficient endurance capacity of the respiratory muscles. Anabolic steroids may improve respiratory muscle function in COPD. The effect of anabolic steroids on mitochondrial function in the diaphragm in emphysema is unknown. In an emphysematous male hamster model, we investigated whether administration of the anabolic steroid nandrolone decanoate (ND) altered the activity of mitochondrial respiratory chain complexes in the diaphragm. The bodyweight of hamsters treated with ND was decreased after treatment compared with initial values, and serum testosterone levels were significantly lower in hamsters treated with ND than in control hamsters. No difference in the activity of mitochondrial respiratory chain complexes in the diaphragm between normal and emphysematous hamsters was observed. Treatment with ND did not change the activity of mitochondrial respiratory chain complexes in the diaphragm of both normal and emphysematous hamsters. In emphysematous hamsters, administration of ND decreased the activity of succinate:cytochrome c oxidoreductase compared with ND treatment in normal hamsters. We conclude that anabolic steroids have negative effects on the activity of succinate:cytochrome c oxidoreductase and anabolic status in this emphysematous hamster model.

Mitochondrial function in diaphragm of emphysematous hamsters after treatment with nandrolone

PubMed Central

Wijnhoven, Hanneke JH; Ennen, Leo; Rodenburg, Richard JT; Dekhuijzen, PN Richard

2006-01-01

Respiratory failure in patients with COPD may be caused by insufficient force production or insufficient endurance capacity of the respiratory muscles. Anabolic steroids may improve respiratory muscle function in COPD. The effect of anabolic steroids on mitochondrial function in the diaphragm in emphysema is unknown. In an emphysematous male hamster model, we investigated whether administration of the anabolic steroid nandrolone decanoate (ND) altered the activity of mitochondrial respiratory chain complexes in the diaphragm. The bodyweight of hamsters treated with ND was decreased after treatment compared with initial values, and serum testosterone levels were significantly lower in hamsters treated with ND than in control hamsters. No difference in the activity of mitochondrial respiratory chain complexes in the diaphragm between normal and emphysematous hamsters was observed. Treatment with ND did not change the activity of mitochondrial respiratory chain complexes in the diaphragm of both normal and emphysematous hamsters. In emphysematous hamsters, administration of ND decreased the activity of succinate:cytochrome c oxidoreductase compared with ND treatment in normal hamsters. We conclude that anabolic steroids have negative effects on the activity of succinate:cytochrome c oxidoreductase and anabolic status in this emphysematous hamster model. PMID:18046906

Transmission and adaptation of chronic wasting disease to hamsters and transgenic mice: evidence for strains.

PubMed

Raymond, Gregory J; Raymond, Lynne D; Meade-White, Kimberly D; Hughson, Andrew G; Favara, Cynthia; Gardner, Donald; Williams, Elizabeth S; Miller, Michael W; Race, Richard E; Caughey, Byron

2007-04-01

In vitro screening using the cell-free prion protein conversion system indicated that certain rodents may be susceptible to chronic wasting disease (CWD). Therefore, CWD isolates from mule deer, white-tailed deer, and elk were inoculated intracerebrally into various rodent species to assess the rodents' susceptibility and to develop new rodent models of CWD. The species inoculated were Syrian golden, Djungarian, Chinese, Siberian, and Armenian hamsters, transgenic mice expressing the Syrian golden hamster prion protein, and RML Swiss and C57BL10 wild-type mice. The transgenic mice and the Syrian golden, Chinese, Siberian, and Armenian hamsters had limited susceptibility to certain of the CWD inocula, as evidenced by incomplete attack rates and long incubation periods. For serial passages of CWD isolates in Syrian golden hamsters, incubation periods rapidly stabilized, with isolates having either short (85 to 89 days) or long (408 to 544 days) mean incubation periods and distinct neuropathological patterns. In contrast, wild-type mouse strains and Djungarian hamsters were not susceptible to CWD. These results show that CWD can be transmitted and adapted to some species of rodents and suggest that the cervid-derived CWD inocula may have contained or diverged into at least two distinct transmissible spongiform encephalopathy strains.

Caffeine induces metformin anticancer effect on fibrosarcoma in hamsters.

PubMed

Popović, D J; Lalošević, D; Miljković, D; Popović, K J; Čapo, I; Popović, J K

2018-04-01

We investigated the effect of metformin and caffeine on fibrosarcoma in hamsters. 32 Syrian golden hamsters of both sexes, weighing approximately 100 g, were randomly allocated to 3 experimental and 2 control groups, with a minimum of 6 animals per group. 2 x 106 BHK-21/C13 cells in 1 ml were injected subcutaneously into the animals' back in 4 groups. The first experimental group started peroral treatment with metformin 500 mg/kg daily, the second with caffeine 100 mg/kg daily and the third with a combination of metformin 500 mg/kg and caffeine 100 mg/kg daily, via a gastric probe 3 days before tumor inoculation. After 2 weeks, when the tumors were approximately 2 cm in the control group, all animals were sacrificed. The blood was collected for glucose and other analyses. The tumors were excised and weighed and their diameters were measured. The tumor samples were pathohistologically (HE) and immunohistochemically (Ki-67, CD 31, COX IV, GLUT-1, iNOS) assessed and the main organs toxicologically analyzed, including the control animals that had received metformin and caffeine. Tumor volume was determined using the formula LxS2/2, where L was the longest and S the shortest diameter. Ki-67-positive cells in the tumor samples were quantified. Images were taken and processed by software UTHSCSA Image Tools for Windows Version 3.00. Statistical significances were determined by the Student's t-test. The combination of metformin and caffeine inhibited fibrosarcoma growth in hamsters without toxicity. Administration of metformin with caffeine might be an effective and safe approach in novel nontoxic adjuvant anticancer treatment.

Long-term carcinogenicity study in Syrian golden hamster of particulate emissions from coal- and oil-fired power plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Persson, S.A.; Ahlberg, M.; Berghem, L.

1988-04-01

Male Syrian golden hamsters were given 15 weekly intratracheal instillations with suspensions of coal fly ash or oil fly ash. Controls were instilled with saline containing gelatine (0.5 g/100 mL) or to check particle effects with suspensions of hematite (Fe/sub 2/O/sub 3/). The common weekly dose was 4.5 mg/hamster. In addition, one subgroup of hamsters was treated with oil fly ash at a weekly dose of 3.0 mg/hamster and another with coal fly ash at a weekly dose of 6.0 mg/hamster. Other groups of hamsters were treated with suspensions of benzo(a)pyrene (BaP) or with suspensions on coal fly ash, oilmore » fly ash, or Fe/sub 2/O/sub 3/ coated with BaP. The mass median aerodynamic diameters of the coal and oil fly ashes were 4.4 microns and 28 microns, respectively. Hamsters treated with oil fly ash showed a higher frequency of bronchiolar-alveolar hyperplasia than hamsters in the other treatment groups. Squamous dysplasia and squamous metaplasia were most frequent in animals treated with suspensions of BaP or BaP-coated particles. The earliest appearance of a tumor, the highest incidence of tumors, and the highest incidence of malignant tumors were observed in hamsters treated with oil fly ash coated with BaP. Squamous cell carcinoma and adenosquamous carcinoma were the most frequent malignant tumors. No malignant tumors and only few benign tumors were observed in hamsters instilled with suspensions of fly ash not coated with BaP. The present study gives no indication that coal fly ash could create more serious health problems than oil fly ash.« less

Heat and cold acclimation in helium-cold hypothermia in the hamster.

NASA Technical Reports Server (NTRS)

Musacchia, X. J.

1972-01-01

A study was made of the effects of acclimation of hamsters to high (34-35 C) and low (4-5 C) temperatures for periods up to 6 weeks on the induction of hypothermia in hamsters. Hypothermia was achieved by exposing hamsters to a helox mixture of 80% helium and 20% oxygen at 0 C. Hypothermic induction was most rapid (2-3 hr) in heat-acclimated hamsters and slowest (6-12 hr) in cold-acclimated hamsters. The induction period was intermediate (5-8 hr) in room temperature nonacclimated animals (controls). Survival time in hypothermia was relatable to previous temperature acclimations. The hypothesis that thermogenesis in cold-acclimated hamsters would accentuate resistance to induction of hypothermia was substantiated.

Understanding Transcriptional Enhancement in Monoclonal Antibody-Producing Chinese Hamster Ovary Cells

NASA Astrophysics Data System (ADS)

Nicoletti, Sarah E.

With the demand for monoclonal antibody (mAB) therapeutics continually increasing, the need to better understand what makes a high productivity clone has gained substantial interest. Monoclonal antibody producing Chinese hamster ovary (CHO) cells with different productivities were provided by a biopharmaceutical company for investigation. Gene copy numbers, mRNA levels, and mAb productivities were previously determined for two low producing clones and their amplified progeny. These results showed an increase in mRNA copy number in amplified clones, which correlated to the observed increases in specific productivity of these clones. The presence of multiple copies of mRNA per one copy of DNA in the higher productivity clones has been coined as transcriptional enhancement. The methylation status of the CMV promoter as well as transcription factor/promoter interactions were evaluated to determine the cause of transcriptional enhancement. Methylation analysis via bisulfite sequencing revealed no significant difference in overall methylation status of the CMV promoter. These data did, however, reveal the possibility of differential interactions of transcription factors between the high and low productivity cell clones. This finding was further supported by chromatin immunoprecipitations previously performed in the lab, as well as literature studies. Transcription activator-like effector (TALE) binding proteins were constructed and utilized to selectively immunoprecipitate the CMV promoter along with its associated transcription factors in the different CHO cell clones. Cells were transfected with the TALE proteins, harvested and subjected to a ChIP-like procedure. Results obtained from the TALE ChIP demonstrated the lack of binding of the protein to the promoter and the need to redesign the TALE. Overall, results obtained from this study were unable to give a clear indication as to the causes of transcriptional enhancement in the amplified CHO cell clones. Further

Cell cycle progression in irradiated endothelial cells cultured from bovine aorta

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rubin, D.B.; Drab, E.A.; Ward, W.F.

1988-11-01

Logarithmically growing endothelial cells from bovine aortas were exposed to single doses of 0-10 Gy of 60Co gamma rays, and cell cycle phase distribution and progression were examined by flow cytometry and autoradiography. In some experiments, cells were synchronized in the cell cycle with hydroxyurea (1 mM). Cell number in sham-irradiated control cultures doubled in approximately 24 h. Estimated cycle stage times for control cells were 14.4 h for G1 phase, 7.2 h for S phase, and 2.4 h for G2 + M phase. Irradiated cells demonstrated a reduced distribution at the G1/S phase border at 4 h, and anmore » increased distribution in G2 + M phase at 24 h postirradiation. Autoradiographs of irradiated cells after continuous (3H)thymidine labeling indicated a block in G1 phase or at the G1/S-phase border. The duration of the block was dose dependent (2-3 min/cGy). Progression of the endothelial cells through S phase after removal of the hydroxyurea block also was retarded by irradiation, as demonstrated by increased distribution in early S phase and decreased distribution in late S phase. These results indicate that progression of asynchronous cultured bovine aortic endothelial cells through the DNA synthetic cycle is susceptible to radiation inhibition at specific sites in the cycle, resulting in redistribution and partial synchronization of the population. Thus aortic endothelial cells, diploid cells from a normal tissue, resemble many immortal cell types that have been examined in this regard in vitro.« less

Reaction of long-lived radicals and vitamin C in γ-irradiated mammalian cells and their model system at 295 K. Tunneling reaction in biological system

NASA Astrophysics Data System (ADS)

Matsumoto, Takuro; Miyazaki, Tetsuo; Kosugi, Yoshio; Kumada, Takayuki; Koyama, Sinji; Kodama, Seiji; Watanabe, Masami

1997-05-01

When golden hamster embryo (GHE) cells or concentrated albumin solution (0.1 kg dm -3) that is a model system of cells is irradiated with γ-rays at 295 K, organic radicals produced can be observed by ESR. The organic radicals survive at both 295 and 310 K for such a long time as 20 h. The long-lived radicals in GHE cells and the albumin solution react with vitamin C by the rate constants of 0.007 dm 3 mol -1 s -1 and 0.014 dm 3 mol -1 s -1, respectively. The long-lived radicals in human cells cause gene mutation, which is suppressed by addition of vitamin C. The isotope effect on the rate constant ( k) for the reaction of the long-lived radicals and vitamin C has been studied in the albumin solution by use of protonated vitamin C and deuterated vitamin C. The isotope effect ( kH/ kD) was more than 20 ≈ 50 and was interpreted in terms of tunneling reaction.

A I-V analysis of irradiated Gallium Arsenide solar cells

NASA Technical Reports Server (NTRS)

Heulenberg, A.; Maurer, R. H.; Kinnison, J. D.

1991-01-01

A computer program was used to analyze the illuminated I-V characteristics of four sets of gallium arsenide (GaAs) solar cells irradiated with 1-MeV electrons and 10-MeV protons. It was concluded that junction regions (J sub r) dominate nearly all GaAs cells tested, except for irradiated Mitsubishi cells, which appear to have a different doping profile. Irradiation maintains or increases the dominance by J sub r. Proton irradiation increases J sub r more than does electron irradiation. The U.S. cells were optimized for beginning of life (BOL) and the Japanese for end of life (EOL). I-V analysis indicates ways of improving both the BOL and EOL performance of GaAs solar cells.

Effects of porcine pancreatic enzymes on the pancreas of hamsters. Part 2: carcinogenesis studies.

PubMed

Nozawa, Fumiaki; Yalniz, Mehmet; Saruc, Murat; Standop, Jens; Egami, Hiroshi; Pour, Parviz M

2012-09-10

Our previous study suggested that porcine pancreatic extract in hamsters with peripheral insulin resistance, normalizes insulin output, islet size and pancreatic DNA synthetic rate. It also inhibited the growth of human pancreatic cancer cells in nude mice. To examine the potential value of the porcine pancreatic extract in controlling pancreatic carcinogenesis in this model, the present experiment was performed. Hamsters were fed a high fat diet and four weeks later when insulin resistance emerges, they were divided into two groups. One group received 1 g/kg BW of porcine pancreatic extract in drinking water and the other group received tap water. One week later, when insulin output normalizes in porcine pancreatic extract-treated hamsters, a single subcutaneous injection of N-nitrosobis-(2-oxopropyl) amine (BOP) at a dose of 40 mg/kg BW was given to all hamsters. The experiment was terminated at 43 weeks after the porcine pancreatic extract treatment. The number and size of pancreatic tumors, blood glucose, insulin, amylase and lipase levels, the average size of islets and the number of insulin cells/islets were determined. The incidence of pancreatic cancer was significantly lower in the porcine pancreatic extract group (P=0.043), as well as the plasma insulin level and the size of the islets in the porcine pancreatic extract group were significantly lower (P<0.001) than in the control group. No significantly differences were found in the glucose level between the groups. These results show that porcine pancreatic extract has a potential to inhibit pancreatic cancer growth.

Irradiation induces glioblastoma cell senescence and senescence-associated secretory phenotype.

PubMed

Jeon, Hee-Young; Kim, Jun-Kyum; Ham, Seok Won; Oh, Se-Yeong; Kim, Jaebong; Park, Jae-Bong; Lee, Jae-Yong; Kim, Sung-Chan; Kim, Hyunggee

2016-05-01

Glioblastoma multiforme (GBM) is one of the most aggressive and fatal primary brain tumors in humans. The standard therapy for the treatment of GBM is surgical resection, followed by radiotherapy and/or chemotherapy. However, the frequency of tumor recurrence in GBM patients is very high, and the survival rate remains poor. Delineating the mechanisms of GBM recurrence is essential for therapeutic advances. Here, we demonstrate that irradiation rendered 17-20 % of GBM cells dead, but resulted in 60-80 % of GBM cells growth-arrested with increases in senescence markers, such as senescence-associated beta-galactosidase-positive cells, H3K9me3-positive cells, and p53-p21(CIP1)-positive cells. Moreover, irradiation induced expression of senescence-associated secretory phenotype (SASP) mRNAs and NFκB transcriptional activity in GBM cells. Strikingly, compared to injection of non-irradiated GBM cells into immune-deficient mice, the co-injection of irradiated and non-irradiated GBM cells resulted in faster growth of tumors with the histological features of human GBM. Taken together, our findings suggest that the increases in senescent cells and SASP in GBM cells after irradiation is likely one of main reasons for tumor recurrence in post-radiotherapy GBM patients.

X-irradiation of human bronchial cancer cells causes the bystander effects in normal bronchial cells in vitro.

PubMed

Konopacka, M; Rogoliński, J

2010-01-01

Using X radiation commonly used in radiotherapy of cancers we investigated bystander interactions between human cells: irradiated A549 bronchial carcinoma human cells and non irradiated BEAS-2B normal bronchial epithelial cells. Non irradiated cells were incubated in medium transferred from irradiated A549 cells (ICM-irradiation conditioned medium) for 48h and next the chromosomal damage and apoptosis were estimated. Conditioned medium collected from irradiated cancer cells induced in non irradiated cells of the same line as well as in BEAS-2B normal cells genetic changes such as micronuclei, chromatid and chromosomal breaks and condensation of chromatin characteristic for processes of apoptosis. Addition of only 1% of conditioned medium to fresh medium was sufficient to induction of bystander response to normal bronchial cells. The presented results in this study could have implications for human radiation risk and in evaluating the secondary effects of radiotherapy.

Directed Student Inquiry: Modeling in Roborovsky Hamsters

ERIC Educational Resources Information Center

Elwess, Nancy L.; Bouchard, Adam

2007-01-01

In this inquiry-based activity, Roborovsky hamsters are used to provide students with an opportunity to develop their skills of analysis, inquiry, and design. These hamsters are easy to maintain, yet offer students a means to use conventional techniques and those of their own design to make further observations through measuring, assessing, and…

Pineal melatonin synthesis in Syrian hamsters: A summary

NASA Astrophysics Data System (ADS)

Rollag, M. D.

1982-12-01

During the past decade there has been ample documentation of the proposition that the pineal gland mediates photoperiodic influences upon reproductive behavior of hamsters. It is commonly hypothesized that the pineal gland expresses its activity by transformation of photoperiodic information into an hormonal output, that hormone being melatonin. If this hypothesis is correct, there must be some essential diffrence in melatonin's output when hamsters are exposed to different photoperiodic environments. The experiments summarized in this communication analyze pineal melatonin contents in Syrian hamsters maintained in a variety of photoperiodic conditions during different physiological states. The results demonstrate that adult hamsters have a daily surge in pineal melatonin content throughout their lifetime when exposed to simulated annual photoperiodic cycles. There is some fluctuation in the amount of pineal melatonin produced during different physiological states and photoperiodic environments, but these fluctuations seem small when compared to those normally found for other regulatory hormones. When hamsters are exposed to different photoperiodic regimens, the daily melatonin surge maintains a relatively constant phase relationship with respect to the onset of daily activity. There is a concomitant change in its phase relationship with respect to light-dark transitions.

Fasting-induced daily torpor in desert hamsters (Phodopus roborovskii).

PubMed

Chi, Qing-Sheng; Wan, Xin-Rong; Geiser, Fritz; Wang, De-Hua

2016-09-01

Daily torpor is frequently expressed in small rodents when facing energetically unfavorable ambient conditions. Desert hamsters (Phodopus roborovskii, ~20g) appear to be an exception as they have been described as homeothermic. However, we hypothesized that they can use torpor because we observed reversible decreases of body temperature (Tb) in fasted hamsters. To test this hypothesis we (i) randomly exposed fasted summer-acclimated hamsters to ambient temperatures (Tas) ranging from 5 to 30°C or (ii) supplied them with different rations of food at Ta 23°C. All desert hamsters showed heterothermy with the lowest mean Tb of 31.4±1.9°C (minimum, 29.0°C) and 31.8±2.0°C (minimum, 29.0°C) when fasted at Ta of 23°C and 19°C, respectively. Below Ta 19°C, the lowest Tb and metabolic rate increased and the proportion of hamsters using heterothermy declined. At Ta 5°C, nearly all hamsters remained normothermic by increasing heat production, suggesting that the heterothermy only occurs in moderately cold conditions, perhaps to avoid freezing at extremely low Tas. During heterothermy, Tbs below 31°C with metabolic rates below 25% of those during normothermia were detected in four individuals at Ta of 19°C and 23°C. Consequently, by definition, our observations confirm that fasted desert hamsters are capable of shallow daily torpor. The negative correlation between the lowest Tbs and amount of food supply shows that heterothermy was mainly triggered by food shortage. Our data indicate that summer-acclimated desert hamsters can express fasting-induced shallow daily torpor, which may be of significance for energy conservation and survival in the wild. Copyright © 2016 Elsevier Inc. All rights reserved.

Pleural dosimetry and pathobiological responses in rats and hamsters exposed subchronically to MMVF 10a fiberglass.

PubMed

Bermudez, Edilberto; Mangum, James B; Moss, Owen R; Wong, Brian A; Everitt, Jeffrey I

2003-07-01

Interspecies differences in pulmonary and pleural responses to the inhalation of natural mineral and synthetic vitreous fibers have been observed in chronic and subchronic studies. However, the reasons for these differences are not clearly understood. There are also fiber-specific differences in the outcome of chronic inhalation exposure to natural mineral and synthetic vitreous fibers. Whether these differences are dependent upon the ability of these fibers to translocate to the pleural space is unknown. The present study was conducted to compare retained fiber burdens and selected pathological responses in the pleural compartments of rats and hamsters following subchronic inhalation of MMVF 10a fiberglass, a fiber negative for tumorigenesis or fibrosis in chronic studies. Fischer 344 rats and Syrian golden hamsters were exposed for 4 or 12 weeks by nose-only inhalation at nominal aerosol mass concentrations of 45 mg/m3 (610 WHO fibers/cc). Pulmonary fiber burdens and pulmonary inflammatory responses were greater in rats than in hamsters. The total number of fibers in the lung was approximately three orders of magnitude greater than in the pleural compartment. Pleural burdens in the hamster (160 fibers/cm2 surface area) were significantly greater than burdens in similarly exposed rats (60 fibers/cm2 surface area) following 12 weeks of exposure. With time postexposure, pleural burdens decreased in hamsters but were essentially unchanged in rats. Pleural inflammatory responses in both species were minimal. In rats, pleural inflammation was characterized by increased numbers of macrophages and increases in mesothelial cell replication during the period of fiber exposure. In contrast, hamsters had increased numbers of macrophages and lymphocytes, and mesothelial-cell replication indices were elevated on the parietal pleura of the costal wall and diaphragm, with some of these responses persisting through 12 weeks of postexposure recovery. Taken together, the results

The fluidity of Chinese hamster ovary cell and bull sperm membranes after cholesterol addition.

PubMed

Purdy, P H; Fox, M H; Graham, J K

2005-08-01

Cell plasma membrane fluidity is affected by membrane lipid and protein composition as well as temperature. Altering the cholesterol content of a membrane can change membrane fluidity at different temperatures and this may affect cell survival during cryopreservation. In these experiments, we examined the effect that adding cholesterol to the membranes of Chinese hamster ovary cells (CHO) and bull sperm had on cell plasma membrane fluidity and cell survival when cells were cooled to 5 degrees C or were cryopreserved. Cells were treated with 0, 1.5 or 5.0mg cholesterol-loaded cyclodextrin (CLC), stained with N-((4-(6-phenyl-1,3,5-hexatrienyl)phenyl)propyl)trimethylammonium-p-toluenesulfonate (TMAP-DPH) to evaluate membrane fluidity and with propidium iodide to evaluate cell viability, prior to analysis by flow cytometry at 23, 5 degrees C, and after cryopreservation. CHO cells exhibited a single cell population with all cells having similar membrane fluidity. Membrane fluidity did not change when temperature had been reduced and then returned to 23 degrees C (P<0.05), however, adding cholesterol to the cells induced membranes to become more rigid (P<0.05). Bull sperm samples consisted of two cell subpopulations, one having relatively higher membrane fluidity than the other, regardless of cholesterol treatment or temperature. In addition, cells possessing the highest membrane fluidity did not survive cooling or cryopreservation efficiently. CLC treatment did not significantly alter membrane fluidity after temperature changes, but did maintain higher percentages of spermatozoa surviving cooling to 5 degrees C and cryopreservation (P<0.05). In conclusion, adding cholesterol to cell resulted in detectable membrane fluidity changes in CHO cells and increased survival of bull sperm after cooling to 5 degrees C and after cryopreservation.

Resistance of hypoxic cells to ionizing radiation is influenced by homologous recombination status

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sprong, Debbie; Janssen, Hilde L.; Vens, Conchita

2006-02-01

Purpose: To determine the role of DNA repair in hypoxic radioresistance. Methods and Materials: Chinese hamster cell lines with mutations in homologous recombination (XRCC2, XRCC3, BRAC2, RAD51C) or nonhomologous end-joining (DNA-PKcs) genes were irradiated under normoxic (20% oxygen) and hypoxic (<0.1% oxygen) conditions, and the oxygen enhancement ratio (OER) was calculated. In addition, Fanconi anemia fibroblasts (complementation groups C and G) were compared with fibroblasts from nonsyndrome patients. RAD51 foci were studied using immunofluorescence. Results: All hamster cell lines deficient in homologous recombination showed a decrease in OER (1.5-2.0 vs. 2.6-3.0 for wild-types). In contrast, the OER for the DNA-PKcs-deficientmore » line was comparable to wild-type controls. The two Fanconi anemia cell strains also showed a significant reduction in OER. The OER for RAD51 foci formation at late times after irradiation was considerably lower than that for survival in wild-type cells. Conclusion: Homologous recombination plays an important role in determining hypoxic cell radiosensitivity. Lower OERs have also been reported in cells deficient in XPF and ERCC1, which, similar to homologous recombination genes, are known to play a role in cross-link repair. Because Fanconi anemia cells are also sensitive to cross-linking agents, this strengthens the notion that the capacity to repair cross-links determines hypoxic radiosensitivity.« less

Mammalian cells loaded with platinum-containing molecules are sensitized to fast atomic ions.

PubMed

Usami, N; Furusawa, Y; Kobayashi, K; Lacombe, S; Reynaud-Angelin, A; Sage, E; Wu, Ting-Di; Croisy, A; Guerquin-Kern, J-L; Le Sech, C

2008-07-01

This work investigates whether a synergy in cell death induction exists in combining atomic ions irradiation and addition of platinum salts. Such a synergy could be of interest in view of new cancer therapy protocol based on atomic ions--hadrontherapy--with the addition of radiosensitizing agents containing high-Z atoms. The experiment consists in irradiating by fast ions cultured cells previously exposed to dichloroterpyridine Platinum (PtTC) and analyzing cell survival by a colony-forming assay. Chinese Hamster Ovary (CHO) cells were incubated for six hours in medium containing 350 microM PtTC, and then irradiated by fast ions C(6+) and He(2+), with Linear Energy Transfer (LET) within range 2-70 keV/microm. In some experiments, dimethyl sulfoxide (DMSO) was added to investigate the role of free radicals. The intracellular localization of platinum was determined by Nano Secondary Ion Mass Spectroscopy (Nano-SIMS). For all LET examined, cell death rate is largely enhanced when irradiating in presence of PtTC. At fixed irradiation dose, cell death rate increases with increasing LET, while the platinum relative effect is larger at low LET. This finding suggests that hadrontherapy or protontherapy therapeutic index could be improved by combining irradiation procedure with concomitant chemotherapy protocols using platinum salts.

Characteristics of 263K Scrapie Agent in Multiple Hamster Species

PubMed Central

Barbian, Kent D.; Race, Brent; Favara, Cynthia; Gardner, Don; Taubner, Lara; Porcella, Stephen; Race, Richard

2009-01-01

Transmissible spongiform encephalopathy (TSE) diseases are known to cross species barriers, but the pathologic and biochemical changes that occur during transmission are not well understood. To better understand these changes, we infected 6 hamster species with 263K hamster scrapie strain and, after each of 3 successive passages in the new species, analyzed abnormal proteinase K (PK)–resistant prion protein (PrPres) glycoform ratios, PrPres PK sensitivity, incubation periods, and lesion profiles. Unique 263K molecular and biochemical profiles evolved in each of the infected hamster species. Characteristics of 263K in the new hamster species seemed to correlate best with host factors rather than agent strain. Furthermore, 2 polymorphic regions of the prion protein amino acid sequence correlated with profile differences in these TSE-infected hamster species. PMID:19193264

In vitro evaluation of low-intensity light radiation on murine melanoma (B16F10) cells.

PubMed

Peidaee, P; Almansour, N M; Pirogova, E

2016-03-01

Changes in the energy state of biomolecules induced by electromagnetic radiation lead to changes in biological functions of irradiated biomolecules. Using the RRM approach, it was computationally predicted that far-infrared light irradiation in the range of 3500-6000 nm affects biological activity of proto-oncogene proteins. This in vitro study evaluates quantitatively and qualitatively the effects of selected far-infrared exposures in the computationally determined wavelengths on mouse melanoma B16F10 cells and Chinese hamster ovarian (CHO) cells by MTT (thiazolyl blue tetrazolium bromide) cell proliferation assay and confocal laser-scanning microscopy (CLSM). This paper also presents the findings obtained from irradiating B16F10 and CHO cells by the selected wavelengths in visible and near-infrared range. The MTT results show that far-infrared wavelength irradiation induces detrimental effect on cellular viability of B16F10 cells, while that of normal CHO cells is not affected considerably. Moreover, CLSM images demonstrate visible cellular detachment of cancer cells. The observed effects support the hypothesis that far-infrared light irradiation within the computationally determined wavelength range induces biological effect on cancer cells. From irradiation of selected visible and near-infrared wavelengths, no visible changes were detected in cellular viability of either normal or cancer cells.

Effects of porcine pancreatic enzymes on the pancreas of hamsters. Part 1: basic studies.

PubMed

Saruc, Murat; Nozawa, Fumiaki; Yalniz, Mehmet; Itami, Atsushi; Pour, Parviz M

2012-09-10

Porcine pancreatic enzymes (PPE) extracted from glandular stomach has been used for the treatment of pancreatic cancer patients. Unfortunately, no information is available on the in vitro and in vivo effect on the pancreas and other tissues. We used Syrian Golden hamsters, a unique pancreatic cancer model, to obtain basic information on PPE for its eventual use for the treatment of pancreatic cancer. PPE was used in different concentrations in vitro and in vivo. The stability of the enzyme in the water solution was investigated. It was given to the hamsters by gavage in concentrations of 1g/kg and 400 mg/kg for short periods and in aqueous solution for 65 days. Plasma enzyme and insulin, the size of islets and the number of the insulin cells per islet were examined. The enzyme activity of PPE was maintained in water solution for at least 24 hours. Due to its content of calcium chloride it showed a high toxicity to normal and malignant hamster pancreatic cancer cells and human pancreatic cancer cell lines in vitro. PPE did not alter the plasma pancreatic enzyme levels regardless of the dose, duration and application route. On the contrary, PPE reduced their levels significantly. Remarkably, it also reduced the level of insulin, the size of the islets and the number of insulin cells in the islets significantly. The results imply that PPE does not enter the blood circulation but it appears to slow down the function of both the exocrine and endocrine pancreas.

A Systematic Approach to Time-series Metabolite Profiling and RNA-seq Analysis of Chinese Hamster Ovary Cell Culture.

PubMed

Hsu, Han-Hsiu; Araki, Michihiro; Mochizuki, Masao; Hori, Yoshimi; Murata, Masahiro; Kahar, Prihardi; Yoshida, Takanobu; Hasunuma, Tomohisa; Kondo, Akihiko

2017-03-02

Chinese hamster ovary (CHO) cells are the primary host used for biopharmaceutical protein production. The engineering of CHO cells to produce higher amounts of biopharmaceuticals has been highly dependent on empirical approaches, but recent high-throughput "omics" methods are changing the situation in a rational manner. Omics data analyses using gene expression or metabolite profiling make it possible to identify key genes and metabolites in antibody production. Systematic omics approaches using different types of time-series data are expected to further enhance understanding of cellular behaviours and molecular networks for rational design of CHO cells. This study developed a systematic method for obtaining and analysing time-dependent intracellular and extracellular metabolite profiles, RNA-seq data (enzymatic mRNA levels) and cell counts from CHO cell cultures to capture an overall view of the CHO central metabolic pathway (CMP). We then calculated correlation coefficients among all the profiles and visualised the whole CMP by heatmap analysis and metabolic pathway mapping, to classify genes and metabolites together. This approach provides an efficient platform to identify key genes and metabolites in CHO cell culture.

Response of thyroid follicular cells to gamma irradiation compared to proton irradiation. I. Initial characterization of DNA damage, micronucleus formation, apoptosis, cell survival, and cell cycle phase redistribution

NASA Technical Reports Server (NTRS)

Green, L. M.; Murray, D. K.; Bant, A. M.; Kazarians, G.; Moyers, M. F.; Nelson, G. A.; Tran, D. T.

2001-01-01

The RBE of protons has been assumed to be equivalent to that of photons. The objective of this study was to determine whether radiation-induced DNA and chromosome damage, apoptosis, cell killing and cell cycling in organized epithelial cells was influenced by radiation quality. Thyroid-stimulating hormone-dependent Fischer rat thyroid cells, established as follicles, were exposed to gamma rays or proton beams delivered acutely over a range of physical doses. Gamma-irradiated cells were able to repair DNA damage relatively rapidly so that by 1 h postirradiation they had approximately 20% fewer exposed 3' ends than their counterparts that had been irradiated with proton beams. The persistence of free ends of DNA in the samples irradiated with the proton beam implies that either more initial breaks or a quantitatively different type of damage had occurred. These results were further supported by an increased frequency of chromosomal damage as measured by the presence of micronuclei. Proton-beam irradiation induced micronuclei at a rate of 2.4% per gray, which at 12 Gy translated to 40% more micronuclei than in comparable gamma-irradiated cultures. The higher rate of micronucleus formation and the presence of larger micronuclei in proton-irradiated cells was further evidence that a qualitatively more severe class of damage had been induced than was induced by gamma rays. Differences in the type of damage produced were detected in the apoptosis assay, wherein a significant lag in the induction of apoptosis occurred after gamma irradiation that did not occur with protons. The more immediate expression of apoptotic cells in the cultures irradiated with the proton beam suggests that the damage inflicted was more severe. Alternatively, the cell cycle checkpoint mechanisms required for recovery from such damage might not have been invoked. Differences based on radiation quality were also evident in the alpha components of cell survival curves (0.05 Gy(-1) for gamma rays, 0

Sindbis virus glycoproteins are abnormally glycosylated in Chinese hamster ovary cells deprived of glucose.

PubMed

Davidson, S K; Hunt, L A

1985-07-01

We have previously demonstrated that Sindbis virus infection of Chinese hamster ovary (CHO) cells altered the protein glycosylation machinery of the cell, so that both normal, full-size (nine mannose-containing) oligosaccharides and abnormal, "truncated' (five mannose-containing) oligosaccharides are transferred from lipid-linked precursors to newly synthesized viral membrane glycoproteins. In the present studies, we have examined the precursor oligosaccharides on viral glycoproteins that were pulse-labelled with [3H]mannose in the presence or absence of glucose, since glucose starvation of uninfected CHO cells has been reported to induce synthesis of truncated precursor oligosaccharides. Pulse-labelling in the absence of glucose led to a greater than 10-fold increase in the relative amount of the truncated precursor oligosaccharides being transferred to the newly synthesized viral glycoproteins and to an apparent underglycosylation of some precursor viral polypeptides, with some asparaginyl sites not acquiring covalently linked oligosaccharides. The mature virion glycoproteins from CHO cells which were pulse-labelled in the absence of glucose and then 'chased' in the presence of glucose contained proportionately more unusual Man3GlcNAc2-size oligosaccharides. These small neutral-type oligosaccharides were apparently not as good a substrate for further processing into complex acidic-type oligosaccharides as the normal Man5GlcNAc2 intermediate that results from the full-size precursor oligosaccharides.

Short photoperiod-induced ovarian regression is mediated by apoptosis in Siberian hamsters (Phodopus sungorus)

PubMed Central

Moffatt-Blue, C S; Sury, J J; Young, Kelly A

2009-01-01

Siberian hamster reproduction is mediated by photoperiod-induced changes in gonadal activity. However, little is known about how photoperiod induces cellular changes in ovarian function. We hypothesized that exposing female hamsters to short (inhibitory) as opposed to long (control) photoperiods would induce an apoptosis-mediated disruption of ovarian function. Ovaries and plasma from hamsters exposed to either long (LD, 16 h light:8 h darkness) or short (SD, 8 h light:16 h darkness) days were collected during diestrus II after 3, 6, 9 and 12 weeks and processed for histology or RIA respectively. Apoptosis was assessed by in situ TUNEL and active caspase-3 protein immunolabeling. No significant differences were observed among LD hamsters for any parameter; therefore, these control data were pooled. SD exposure induced a decline in preantral follicles (P < 0.05), early antral/antral follicles (P < 0.01) and corpora lutea (P < 0.01) by week 12 as compared with LD. Terminal atretic follicles appeared by SD week 9; by week 12, these had become the predominant ovarian structures. Estradiol concentrations decreased by weeks 9 and 12 SD when compared with both LD and week-3 SD hamsters (P < 0.05); however, no changes were observed for progesterone. TUNEL-positive follicles in SD ovaries increased at week 3 and subsequently declined by week 12 as compared with LD ovaries (P < 0.01). Active capsase-3 protein immunostaining peaked at SD week 3 as compared with all other groups (P < 0.01). TUNEL and capsase-3 immunolabeling were localized to granulosa cells of late-preantral and early-antral/antral follicles. These data indicate that SD exposure rapidly induces follicular apoptosis in Siberian hamsters, which ultimately disrupts both estradiol secretion and folliculogenesis, resulting in the seasonal loss of ovarian function. PMID:16595728

Blood Vessel Normalization in the Hamster Oral Cancer Model for Experimental Cancer Therapy Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ana J. Molinari; Romina F. Aromando; Maria E. Itoiz

Normalization of tumor blood vessels improves drug and oxygen delivery to cancer cells. The aim of this study was to develop a technique to normalize blood vessels in the hamster cheek pouch model of oral cancer. Materials and Methods: Tumor-bearing hamsters were treated with thalidomide and were compared with controls. Results: Twenty eight hours after treatment with thalidomide, the blood vessels of premalignant tissue observable in vivo became narrower and less tortuous than those of controls; Evans Blue Dye extravasation in tumor was significantly reduced (indicating a reduction in aberrant tumor vascular hyperpermeability that compromises blood flow), and tumor bloodmore » vessel morphology in histological sections, labeled for Factor VIII, revealed a significant reduction in compressive forces. These findings indicated blood vessel normalization with a window of 48 h. Conclusion: The technique developed herein has rendered the hamster oral cancer model amenable to research, with the potential benefit of vascular normalization in head and neck cancer therapy.« less

Southern Analysis of Genomic Alterations in Gamma-Ray-Induced Aprt- Hamster Cell Mutants

PubMed Central

Grosovsky, Andrew J.; Drobetsky, Elliot A.; deJong, Pieter J.; Glickman, Barry W.

1986-01-01

The role of genomic alterations in mutagenesis induced by ionizing radiation has been the subject of considerable speculation. By Southern blotting analysis we show here that 9 of 55 (approximately 1/6) gamma-ray-induced mutants at the adenine phosphoribosyl transferase (aprt) locus of Chinese hamster ovary (CHO) cells have a detectable genomic rearrangement. These fall into two classes: intragenic deletions and chromosomal rearrangements. In contrast, no major genomic alterations were detected among 67 spontaneous mutants, although two restriction site loss events were observed. Three gamma-ray-induced mutants were found to be intragenic deletions; all may have identical break-points. The remaining six gamma-ray-induced mutants demonstrating a genomic alteration appear to be the result of chromosomal rearrangements, possibly translocation or inversion events. None of the remaining gamma-ray-induced mutants showed any observable alteration in blotting pattern indicating a substantial role for point mutation in gamma-ray-induced mutagenesis at the aprt locus. PMID:3013724

Molecular analysis of peroxisome proliferation in the hamster.

PubMed

Choudhury, Agharul I; Sims, Helen M; Horley, Neill J; Roberts, Ruth A; Tomlinson, Simon R; Salter, Andrew M; Bruce, Mary; Shaw, P Nicholas; Kendall, David; Barrett, David A; Bell, David R

2004-05-15

Three novel P450 members of the cytochrome P450 4A family were cloned as partial cDNAs from hamster liver, characterised as novel members of the CYP4A subfamily, and designated CYP4A17, 18, and 19. Hamsters were treated with the peroxisome proliferator-activated receptor alpha (PPARalpha) agonists, methylclofenapate (MCP) or Wy-14,643, and shown to develop hepatomegaly and induction of CYP4A17 RNA, and concomitant induction of lauric acid 12- hydroxylase. This treatment also resulted in hypolipidaemia, which was most pronounced in the VLDL fraction, with up to 50% reduction in VLDL-triglycerides; by contrast, blood cholesterol concentration was unaffected by this treatment. These data show that hamster is highly responsive to induction of CYP4A by peroxisome proliferators. To characterise the molecular basis of peroxisome proliferation, the hamster PPARalpha was cloned and shown to encode a 468-amino-acid protein, which is highly similar to rat and mouse PPARalpha proteins. The level of expression of hamster PPARalpha in liver is intermediate between mouse and guinea pig. These results fail to support the hypothesis that the level of PPARalpha in liver is directly responsible for species differences in peroxisome proliferation.

The adaptive immune response does not influence hantavirus disease or persistence in the Syrian hamster

PubMed Central

Prescott, Joseph; Safronetz, David; Haddock, Elaine; Robertson, Shelly; Scott, Dana; Feldmann, Heinz

2013-01-01

Pathogenic New World hantaviruses cause severe disease in humans characterized by a vascular leak syndrome, leading to pulmonary oedema and respiratory distress with case fatality rates approaching 40%. Hantaviruses infect microvascular endothelial cells without conspicuous cytopathic effects, indicating that destruction of the endothelium is not a mechanism of disease. In humans, high levels of inflammatory cytokines are present in the lungs of patients that succumb to infection. This, along with other observations, suggests that disease has an immunopathogenic component. Currently the only animal model available to study hantavirus disease is the Syrian hamster, where infection with Andes virus (ANDV), the primary agent of disease in South America, results in disease that closely mimics that seen in humans. Conversely, inoculation of hamsters with a passaged Sin Nombre virus (SNV), the virus responsible for most cases of disease in North America, results in persistent infection with high levels of viral replication. We found that ANDV elicited a stronger innate immune response, whereas SNV elicited a more robust adaptive response in the lung. Additionally, ANDV infection resulted in significant changes in the blood lymphocyte populations. To determine whether the adaptive immune response influences infection outcome, we depleted hamsters of CD4+ and CD8+ T cells before infection with hantaviruses. Depletion resulted in inhibition of virus-specific antibody responses, although the pathogenesis and replication of these viruses were unaltered. These data show that neither hantavirus replication, nor pathogenesis caused by these viruses, is influenced by the adaptive immune response in the Syrian hamster. PMID:23600567

Effects of Normothermic Conditioned Microwave Irradiation on Cultured Cells Using an Irradiation System with Semiconductor Oscillator and Thermo-regulatory Applicator

PubMed Central

Asano, Mamiko; Sakaguchi, Minoru; Tanaka, Satoshi; Kashimura, Keiichiro; Mitani, Tomohiko; Kawase, Masaya; Matsumura, Hitoshi; Yamaguchi, Takako; Fujita, Yoshikazu; Tabuse, Katsuyoshi

2017-01-01

We investigated the effects of microwave irradiation under normothermic conditions on cultured cells. For this study, we developed an irradiation system constituted with semiconductor microwave oscillator (2.45 GHz) and thermos-regulatory applicator, which could irradiate microwaves at varied output powers to maintain the temperature of cultured cells at 37 °C. Seven out of eight types of cultured cells were killed by microwave irradiation, where four were not affected by thermal treatment at 42.5 °C. Since the dielectric properties such as ε’, ε” and tanδ showed similar values at 2.45 GHz among cell types and media, the degree of microwave energy absorbed by cells might be almost the same among cell types. Thus, the vulnerability of cells to microwave irradiation might be different among cell types. In HL-60 cells, which were the most sensitive to microwave irradiation, the viability decreased as irradiation time and irradiation output increased; accordingly, the decrease in viability was correlated to an increase in total joule. However, when a high or low amount of joules per minute was supplied, the correlation between cellular viability and total joules became relatively weak. It is hypothesized that kinds of cancer cells are efficiently killed by respective specific output of microwave under normothermic cellular conditions. PMID:28145466

Low Doses of Gamma-Irradiation Induce an Early Bystander Effect in Zebrafish Cells Which Is Sufficient to Radioprotect Cells

PubMed Central

Pereira, Sandrine; Malard, Véronique; Ravanat, Jean-Luc; Davin, Anne-Hélène; Armengaud, Jean; Foray, Nicolas; Adam-Guillermin, Christelle

2014-01-01

The term “bystander effect” is used to describe an effect in which cells that have not been exposed to radiation are affected by irradiated cells though various intracellular signaling mechanisms. In this study we analyzed the kinetics and mechanisms of bystander effect and radioadaptation in embryonic zebrafish cells (ZF4) exposed to chronic low dose of gamma rays. ZF4 cells were irradiated for 4 hours with total doses of gamma irradiation ranging from 0.01–0.1 Gy. In two experimental conditions, the transfer of irradiated cells or culture medium from irradiated cells results in the occurrence of DNA double strand breaks in non-irradiated cells (assessed by the number of γ-H2AX foci) that are repaired at 24 hours post-irradiation whatever the dose. At low total irradiation doses the bystander effect observed does not affect DNA repair mechanisms in targeted and bystander cells. An increase in global methylation of ZF4 cells was observed in irradiated cells and bystander cells compared to control cells. We observed that pre-irradiated cells which are then irradiated for a second time with the same doses contained significantly less γ-H2AX foci than in 24 h gamma-irradiated control cells. We also showed that bystander cells that have been in contact with the pre-irradiated cells and then irradiated alone present less γ-H2AX foci compared to the control cells. This radioadaptation effect is significantly more pronounced at the highest doses. To determine the factors involved in the early events of the bystander effect, we performed an extensive comparative proteomic study of the ZF4 secretomes upon irradiation. In the experimental conditions assayed here, we showed that the early events of bystander effect are probably not due to the secretion of specific proteins neither the oxidation of these secreted proteins. These results suggest that early bystander effect may be due probably to a combination of multiple factors. PMID:24667817

Spindle disturbances in human-hamster hybrid (AL) cells induced by mobile communication frequency range signals.

PubMed

Schrader, Thorsten; Münter, Klaus; Kleine-Ostmann, Thomas; Schmid, Ernst

2008-12-01

The production of spindle disturbances in FC2 cells, a human-hamster hybrid (A(L)) cell line, by non-ionizing radiation was studied using an electromagnetic field with a field strength of 90 V/m at a frequency of 835 MHz. Due to the given experimental conditions slide flask cultures were exposed at room temperature in a microTEM (transversal electromagnetic field) cell, which allows optimal experimental conditions for small samples of biological material. Numerical calculations suggest that specific absorption rates of up to 60 mW/kg are reached for maximum field exposure. All exposure field parameters--either measured or calculable--are precisely defined and, for the first time, traceable to the standards of the SI system of physical units. Compared with co-incident negative controls, the results of two independently performed experiments suggest that exposure periods of time from 0.5 to 2 h with an electric field strength of 90 V/m are spindle acting agents as predominately indicated by the appearance of spindle disturbances at the ana- and telophase stages (especially lagging and non-disjunction of single chromosomes) of cell divisions. The spindle disturbances do not change the fraction of mitotic cells with increasing exposure time up to 2 h. Due to the applied experimental conditions an influence of temperature as a confounder parameter for spindle disturbances can be excluded.

Characterization of the Host Response to Pichinde Virus Infection in the Syrian Golden Hamster by Species-Specific Kinome Analysis*

PubMed Central

Falcinelli, Shane; Gowen, Brian B.; Trost, Brett; Napper, Scott; Kusalik, Anthony; Johnson, Reed F.; Safronetz, David; Prescott, Joseph; Wahl-Jensen, Victoria; Jahrling, Peter B.; Kindrachuk, Jason

2015-01-01

The Syrian golden hamster has been increasingly used to study viral hemorrhagic fever (VHF) pathogenesis and countermeasure efficacy. As VHFs are a global health concern, well-characterized animal models are essential for both the development of therapeutics and vaccines as well as for increasing our understanding of the molecular events that underlie viral pathogenesis. However, the paucity of reagents or platforms that are available for studying hamsters at a molecular level limits the ability to extract biological information from this important animal model. As such, there is a need to develop platforms/technologies for characterizing host responses of hamsters at a molecular level. To this end, we developed hamster-specific kinome peptide arrays to characterize the molecular host response of the Syrian golden hamster. After validating the functionality of the arrays using immune agonists of defined signaling mechanisms (lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-α), we characterized the host response in a hamster model of VHF based on Pichinde virus (PICV1) infection by performing temporal kinome analysis of lung tissue. Our analysis revealed key roles for vascular endothelial growth factor (VEGF), interleukin (IL) responses, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, and Toll-like receptor (TLR) signaling in the response to PICV infection. These findings were validated through phosphorylation-specific Western blot analysis. Overall, we have demonstrated that hamster-specific kinome arrays are a robust tool for characterizing the species-specific molecular host response in a VHF model. Further, our results provide key insights into the hamster host response to PICV infection and will inform future studies with high-consequence VHF pathogens. PMID:25573744

A dual near-infrared and dielectric spectroscopies strategy to monitor populations of Chinese hamster ovary cells in bioreactor.

PubMed

Courtès, Franck; Ebel, Bruno; Guédon, Emmanuel; Marc, Annie

2016-05-01

to develop a new strategy combining near-infrared (NIR) and dielectric spectroscopies for real-time monitoring and in-depth characterizing populations of Chinese hamster ovary cells throughout cultures performed in bioreactors. Spectral data processing was based on off-line analyses of the cells, including trypan blue exclusion method, and lactate dehydrogenase activity (LDH). Viable cell density showed a linear correlation with permittivity up to 6 × 10(6) cells ml(-1), while a logarithmic correlation was found between non-lysed dead cell density and conductivity up to 10(7) cells ml(-1). Additionally, partial least square technique was used to develop a calibration model of the supernatant LDH activity based on online NIR spectra with a RMSEC of 55 U l(-1). Considering the LDH content of viable cells measured to be 110 U per 10(9) cells, the lysed dead cell density could be then estimated. These calibration models provided real-time prediction accuracy (R(2) ≥ 0.95) for the three types of cell populations. The high potential of a dual spectroscopy strategy to enhance the online bioprocesses characterization is demonstrated since it allows the simultaneous determination of viable, dead and lysed cell populations in real time.

[The polyploidization characteristics of the hepatocytes of the mouse-like hamster Calomyscus mystax].

PubMed

Anatskaia, O V; Malikov, V G; Meĭer, M N; Kudriavtsev, B N

1995-01-01

A cytophotometric measurement of DNA content in hepatocytes of maturing mouse-like hamsters was made. Cells belonging to ordinary mammalian ploidy classes 2c, 2c x 2, 4c, and 4c x 2 made about 90% of the hepatocyte population. The share of binucleated cells wa high (about 80%), the majority of these cells being 2c X 2 hepatocytes. Binucleated cells with tetraploid and diploid nuclei occur in almost every animal. An average hepatocyte ploidy level in mouse-like hamster is 4.6c. The main peculiarity of parenchymal liver cell populations is that up 5% of hepatocytes contain 3--11 nuclei of different ploidy classes. Multinucleated cells increase in number from 1.5% to 4% within the period from one year (the age of maturation) to two years. Later on their percentage does not change. It is found that in binucleated and multinucleated hepatocytes DNA synthesis can proceed asynchronously. Asynchrony in DNA synthesis elevates as the number of nuclei increases. Among the 2c x 2 and 2c x 3 cells an uneven distribution of 3H-thymidine label can occur, respectively, in 5 and in 50% cases, whereas all the cells with more than 3 nuclei display an uneven an uneven 3H-thymidin label distribution. The formation of multinucleated cells is supposed to be associated with asynchrony in DNA-synthesis in binucleated cells and with the restitution of mitosis.

Alkaline phosphatases contribute to uterine receptivity, implantation, decidualization and defense against bacterial endotoxin in hamsters

PubMed Central

Lei, Wei; Nguyen, Heidi; Brown, Naoko; Ni, Hua; Kiffer-Moreira, Tina; Reese, Jeff; Millán, José Luis; Paria, Bibhash C.

2013-01-01

Alkaline phosphatase (AP) activity has been demonstrated in the uterus of several species, but its importance in the uterus, in general and during pregnancy, is yet to be revealed. In this study, we focused on identifying AP isozyme types, and their hormonal regulation, cell-type and event-specific expression and possible functions in the hamster uterus during the cycle and early pregnancy. Our RT-PCR and in situ hybridization studies demonstrated that among the known Akp2, Akp3, Akp5 and Akp6 murine AP isozyme genes, hamster uteri express only Akp2 and Akp6; and both genes are co-expressed in luminal epithelial cells. Studies in cyclic and ovariectomized hamsters established that while progesterone is the major uterine Akp2 inducer, both progesterone and estrogen are strong Akp6 regulators. Studies in preimplantation uteri showed induction of both genes and the activity of their encoded isozymes in luminal epithelial cells during uterine receptivity. However, at the beginning of implantation, Akp2 showed reduced expression in luminal epithelial cells surrounding the implanted embryo. In contrast, expression of Akp6 and its isozyme was maintained in luminal epithelial cells adjacent to, but not away from, the implanted embryo. Following implantation, stromal transformation to decidua was associated with induced expressions of only Akp2 and its isozyme. We next demonstrated that uterine APs dephosphorylate and detoxify endotoxin lipopolysaccharide at their sites of production and activity. Taken together, our findings suggest that uterine APs contribute to uterine receptivity, implantation, and decidualization in addition to their role in protection of the uterus and pregnancy against bacterial infection. PMID:23929901

Isolation, antimicrobial activities, and primary structures of hamster neutrophil defensins.

PubMed Central

Mak, P; Wójcik, K; Thogersen, I B; Dubin, A

1996-01-01

Hamster (Mesocricetus auratus) neutrophil granules contain at least four microbicidal peptides belonging to the defensin family. These compounds were purified from granule acid extracts by reverse-phase chromatography and termed HaNP-1 to -4 (hamster neutrophil peptide). HaNP-1 and HaNP-3 revealed the most bactericidal activity, with a 50% inhibitory concentration of 0.3 to 0.8 microg/ml for Staphylococcus aureus and Streptococcus pyogenes strains. The HaNP-4 was always isolated in concentrations exceeding about 10 times the concentrations of other hamster peptides, but its antibacterial activity as well as that of HaNP-2 was relatively lower, probably as a result of conserved Arg residue substitutions. Other microorganisms were also tested, and generally, hamster defensins exhibited less potency against gram-negative bacteria. The amino acid sequence of hamster defensins showed a high percentage of identity to the sequence of mouse enteric defensins, reaching about 60% identical residues in the case of HaNP-3 and cryptdin 3. PMID:8890190

[Rabies in the common hamster (Cricetus cricetus) in Slovakia].

PubMed

Svrcek, S; Ondrejka, R; Mlynarcíková, K; Svec, J

1984-11-01

The trials were conducted within the full-scale research on the ecology of lyssa virus. In a period of the mass outbreak of common hamster population in the East Slovakian region, 283 hamsters were examined for rabies. Using the direct immunofluorescence method (DIFM), the rabies antigen was detected in the brain of five hamsters. Three virus strains (denoted as 3 O, 7 E, 9 E) were isolated by means of the inoculation test on sucking mice. On the basis of the detection of the nucleo-protein antigen by DIFM, or its inhibition, detection of the Babes-Negri bodies, determination of the neutralization index, titration on mice and determination of incubation time, the isolated strains were identified as the street strains of rabies virus. As determined by further detailed studies on biological characteristics (determination of the invasiveness index on animals with different susceptibility to rabies virus, determination of pathogenicity for different species of laboratory animals, different weight categories, with different methods of administration, invasiveness index), the "hamster" strains are included among those of intermediate virulence or reduced virulence. At intramuscular administration, the most virulent of the three "hamster" strains studied (3 O) induces a fatal course of rabies in common fox and cat; for wolves, dogs and rabbits it is apathogenic. This strain is also contained in the salivary glands of foxes and cats. In immunofluorescent detection of the rabies nucleoprotein antigen, the "hamster" strains formed a mixed picture of fluorescing particles, characteristic of street strains.

Morphological changes in human melanoma cells following irradiation with thermal neutrons.

PubMed

Barkla, D H; Allen, B J; Brown, J K; Mountford, M; Mishima, Y; Ichihashi, M

1989-01-01

Morphological changes in two human melanoma cell lines, MM96 and MM418, following irradiation with thermal neutrons, were studied using light and electron microscopy. The results show that the response of human malignant melanoma cells to neutron irradiation is both cell line dependent and dose dependent, and that in any given cell line, some cells are more resistant to irradiation than others, thus demonstrating heterogeneity in respect to radiosensitivity. Cells repopulating MM96 flasks after irradiation were morphologically similar to the cells of origin whereas in MM418 flasks cells differentiated into five morphologically distinct subgroups and showed increased melanization. The results also show that radiation causes distinctive morphological patterns of damage although ultrastructural changes unique to the high LET particles released from boron 10 neutron capture are yet to be identified.

Absence of C-type natriuretic peptide receptors in hamster glomeruli.

PubMed

Luk, J K; Wong, E F; Wong, N L

1994-01-01

The distribution of atrial natriuretic peptide receptor B (ANPR-B) varies between tissues and species. The aim of this study is to determine whether ANPR-B is present in the hamster glomeruli. In vitro C-type natriuretic peptide (CNP)- and atrial natriuretic factor (ANF)-stimulated cGMP accumulation studies were performed in hamster glomeruli. Elevated cGMP accumulations were observed upon ANF addition. No cGMP response was seen with CNP. Competitive receptor-binding experiments were performed with 125I-CNP and 125I-ANF against their respective cold peptides in hamster glomeruli. Although no CNP binding was detected, positive ANF binding was found and two types of ANF receptor were demonstrated. The affinity (Kdl) and maximum binding capacity (Bmaxl) of the high-affinity ANF receptor were 0.014 +/- 0.001 nM and 60.4 +/- 10.2 fmol/mg protein, respectively. Those of the low-affinity receptor (Kd2 and Bmax2) were 45.7 +/- 6.2 nM and 28.3 +/- 6.3 pmol/mg protein, respectively. Similarly, saturation binding experiments also failed to show any CNP receptor binding in hamster glomeruli. This finding suggests that ANPR-B is not present in hamster glomeruli and CNP is not a direct physiological regulator of hamster renal function.

Radiosensitivity of Mammalian Cells

PubMed Central

Walters, R. A.; Petersen, D. F.

1968-01-01

Radiation effects on macromolecular synthesis essential for the Chinese hamster cell to traverse the life cycle and to divide have been investigated. Life-cycle analysis techniques employing inhibitors of macromolecular synthesis were used in determining the kinetics of cell growth for specific segments of the population following spontaneous recovery from radiation-induced division delay. The results indicated that recovery does not occur in the absence of functional protein synthesis. Under conditions which inhibit normal RNA and DNA synthesis, irradiated cells can recover the capacity to traverse the life cycle and to divide. The stability of mRNA species coding for proteins essential for division in irradiated cells was also measured. The mean functional lifetime of these mRNA species was 1 hr. The data demonstrate the existence of a specific segment of the population consisting of cells which have completed transcription related to division but not concomitant translation and which can recover from the radiation injury without synthesis of additional RNA. Thus, initial recovery of the ability to divide has an obligate requirement for protein synthesis but no corresponding requirement for nucleic acid synthesis during the period when original messenger remains intact. PMID:5753224

Systematization of the Mechanism by Which Plasma Irradiation Causes Cell Growth and Tumor Cell Death

NASA Astrophysics Data System (ADS)

Shimizu, Nobuyuki

2015-09-01

New methods and technologies have improved minimally invasive surgical treatment and saved numerous patients. Recently, plasma irradiation has been demonstrated that might be useful in medical field and the plasma irradiation device is expected to become practically applicable. Mild plasma coagulator showed some advantages such as hemostasis and adhesion reduction in experimental animal model, but the mechanism of plasma irradiation remains unclear. Our study group aim to clarify the mechanism of plasma irradiation effects, mainly focusing on oxidative stress using cultured cell lines and small animal model. First, a study using cultured cell lines showed that the culture medium that was activated by plasma irradiation (we called this kind of medium as ``PAM'' -plasma activated medium-) induced tumor cell death. Although this effect was mainly found to be due to hydrogen peroxide, the remaining portion was considered as the specific effect of the plasma irradiation and we are now studying focusing on this effect. Second, we established a mouse intra-peritoneal adhesion model and checked biological reaction that occurred in the adhesion part. Histopathological study showed inflammatory cells infiltration into adhesion part and the expression of PTX3 that might involve tissue repair around adhesion part. We also confirmed that cytokines IL-6 and IL-10 might be useful as a marker of adhesion formation in this model. Applying ``PAM'' or mild plasma irradiation in this model, we examine the effects of plasma on inflamed cells. The samples in these experiments would be applied to targeted proteomics analysis, and we aim to demonstrate the systematization of the cell's reaction by plasma irradiation.

Caffeine toxicity is inversely related to DNA repair in simian virus 40-transformed xeroderma pigmentosum cells irradiated with ultraviolet light

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cleaver, J.E.

1989-01-01

Human cells transformed by simian virus 40 (SV40) are more sensitive to killing by ultraviolet light when grown in caffeine after irradiation. The degree of sensitization at 2 mM caffeine (expressed as the ratio of the 37% survival dose for control cells divided by the 37% survival dose for cells grown in caffeine, i.e., the dose modification factor) was approximately 1.9 in transformed normal cells and 3.8-5.8 in excision-defective xeroderma pigmentosum (XP) groups A, C, and D cells. A large dose modification factor of 12 was observed in a transformed XP variant cell line. Chinese hamster ovary cells were notmore » significantly different from transformed normal human cells, with a maximum dose modification factor of 1.5. Two radioresistant XP revertants that do not excise cyclobutane dimers gave different responses; one resembled its group A parent in being sensitized by caffeine, and one did not. These results can be interpreted on the basis of a single hypothesis that cells are killed as a result of attempts to replicate damaged DNA. Increased replication rates caused by transformation, increased numbers of replication forks in DNA caused by caffeine, and increased numbers of damaged sites ahead of replication forks in excision-defective cells are all processes that will consequently increase killing according to this hypothesis. A corollary is that the XP variant may be highly sensitized to caffeine because of excision defects at the DNA replication forks, an idea that may be important in designing cloning strategies for the XP variant gene.« less

Melatonin alleviates hyperthyroidism induced oxidative stress and neuronal cell death in hippocampus of aged female golden hamster, Mesocricetus auratus.

PubMed

Rao, Geeta; Verma, Rakesh; Mukherjee, Arun; Haldar, Chandana; Agrawal, Neeraj Kumar

2016-09-01

Oxidative stress is a well known phenomenon under hyperthyroid condition that induces various physiological and neural problems with a higher prevalence in females. We, therefore investigated the antioxidant potential of melatonin (Mel) on hyperthyroidism-induced oxidative stress and neuronal cell death in the hippocampus region of brain (cognition and memory centre) of aged female golden hamster, Mesocricetus auratus. Aged female hamsters were randomly divided into four experimental groups (n=7); group-I: control, group-II: Melatonin (5mgkg(-1)day(-1), i.p., for one week), group-III: Hyperthyroid (100μg kg(-1)day(-1), i.p., for two weeks) and group-IV- Hyper+Mel. Hormonal profiles (thyroid and melatonin), activity of antioxidant enzymes (SOD, CAT and GPX), lipid peroxidation level (TBARS) and the specific apoptotic markers (Bax/Bcl-2 ratio and Caspase-3) expression were evaluated. A significant increase in the profile of total thyroid hormone (tT3 and tT4) in hyperthyroidic group as compared to control while tT3 significantly decreased in melatonin treated hyperthyroidic group. However, Mel level significantly decreased in hyperthyroidic group but increased in melatonin treated hyperthyroidic group. Further, the number of immune-positive cells for thyroid hormone receptor-alpha (TR-α) decreased in the hippocampus of hyperthyroidic group and increased in melatonin treated hyperthyroidic group. Profiles of antioxidant enzymes showed a significant decrease in hyperthyroidic group with a simultaneous increase in lipid peroxidation (TBARS). Melatonin treatment to hyperthyroidic group lead to decreased TBARS level with a concomitant increase in antioxidant enzyme activity. Moreover, increased expression of Bax/Bcl-2 ratio and Caspase-3, in hyperthyroidic group had elevated neuronal cell death in hippocampal area and melatonin treatment reduced its expression in hyperthyroidic group. Our findings thus indicate that melatonin reduced the hyperthyroidism

The adaptive immune response does not influence hantavirus disease or persistence in the Syrian hamster.

PubMed

Prescott, Joseph; Safronetz, David; Haddock, Elaine; Robertson, Shelly; Scott, Dana; Feldmann, Heinz

2013-10-01

Pathogenic New World hantaviruses cause severe disease in humans characterized by a vascular leak syndrome, leading to pulmonary oedema and respiratory distress with case fatality rates approaching 40%. Hantaviruses infect microvascular endothelial cells without conspicuous cytopathic effects, indicating that destruction of the endothelium is not a mechanism of disease. In humans, high levels of inflammatory cytokines are present in the lungs of patients that succumb to infection. This, along with other observations, suggests that disease has an immunopathogenic component. Currently the only animal model available to study hantavirus disease is the Syrian hamster, where infection with Andes virus (ANDV), the primary agent of disease in South America, results in disease that closely mimics that seen in humans. Conversely, inoculation of hamsters with a passaged Sin Nombre virus (SNV), the virus responsible for most cases of disease in North America, results in persistent infection with high levels of viral replication. We found that ANDV elicited a stronger innate immune response, whereas SNV elicited a more robust adaptive response in the lung. Additionally, ANDV infection resulted in significant changes in the blood lymphocyte populations. To determine whether the adaptive immune response influences infection outcome, we depleted hamsters of CD4(+) and CD8(+) T cells before infection with hantaviruses. Depletion resulted in inhibition of virus-specific antibody responses, although the pathogenesis and replication of these viruses were unaltered. These data show that neither hantavirus replication, nor pathogenesis caused by these viruses, is influenced by the adaptive immune response in the Syrian hamster. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Isolation and characterization of a Chinese hamster ovary cell mutant with altered regulation of phosphatidylserine biosynthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasegawa, K.; Kuge, O.; Nishijima, M.

1989-11-25

We have screened approximately 10,000 colonies of Chinese hamster ovary (CHO) cells immobilized on polyester cloth for mutants defective in (14C)ethanolamine incorporation into trichloroacetic acid-precipitable phospholipids. In mutant 29, discovered in this way, the activities of enzymes involved in the CDP-ethanolamine pathway were normal; however, the intracellular pool of phosphorylethanolamine was elevated, being more than 10-fold that in the parental CHO-K1 cells. These results suggested that the reduced incorporation of (14C)ethanolamine into phosphatidylethanolamine in mutant 29 was due to dilution of phosphoryl-(14C)ethanolamine with the increased amount of cellular phosphorylethanolamine. Interestingly, the rate of incorporation of serine into phosphatidylserine and themore » content of phosphatidylserine in mutant 29 cells were increased 3-fold and 1.5-fold, respectively, compared with the parent cells. The overproduction of phosphorylethanolamine in mutant 29 cells was ascribed to the elevated level of phosphatidylserine biosynthesis, because ethanolamine is produced as a reaction product on the conversion of phosphatidylethanolamine to phosphatidylserine, which is catalyzed by phospholipid-serine base-exchange enzymes. Using both intact cells and the particulate fraction of a cell extract, phosphatidylserine biosynthesis in CHO-K1 cells was shown to be inhibited by phosphatidylserine itself, whereas that in mutant 29 cells was greatly resistant to the inhibition, compared with the parental cells. As a conclusion, it may be assumed that mutant 29 cells have a lesion in the regulation of phosphatidylserine biosynthesis by serine-exchange enzyme activity, which results in the overproduction of phosphatidylserine and phosphorylethanolamine as well.« less

The effect of pinealectomy, melatonin and leptin hormones on ovarian follicular development in female Syrian hamsters (Mesocricetus auratus).

PubMed

Karakaş, A; Kaya, Aliye; Gündüz, B

2010-12-01

We studied the effects of melatonin and leptin hormones on ovarian follicular development in intact and pinealectomized female Syrian hamsters. We first monitored the oestrous cycle of the hamsters by the vaginal smear samples throughout a ten day period to start the injections simultaneously in all groups and performed saline, melatonin and leptin hormone injection groups for both control and pinealectomized hamsters. Then the injections were applied for four days starting the oestrus phase of the cycle and the ovaries were removed for preparation of histological analysis. We measured the diameters and the numbers of the follicles and we classified the follicles according to the number of the granulosa cell layer. Leptin hormone injection increased melatonin hormone injection decreased the number and the diameter of the follicles. The stimulating effect of the leptin hormone was more pronounced in the pinealectomized group. The results of the present study indicate that the removal of the pineal gland and leptin hormone administration are playing a stimulatory while melatonin hormone administration is playing an inhibitory role on the follicular development in female Syrian hamsters.

The Syrian hamster model of hantavirus pulmonary syndrome.

PubMed

Safronetz, David; Ebihara, Hideki; Feldmann, Heinz; Hooper, Jay W

2012-09-01

Hantavirus pulmonary syndrome (HPS) is a relatively rare, but frequently fatal disease associated with New World hantaviruses, most commonly Sin Nombre and Andes viruses in North and South America, respectively. It is characterized by fever and the sudden, rapid onset of severe respiratory distress and cardiogenic shock, which can be fatal in up to 50% of cases. Currently there are no approved antiviral therapies or vaccines for the treatment or prevention of HPS. A major obstacle in the development of effective medical countermeasures against highly pathogenic agents like the hantaviruses is recapitulating the human disease as closely as possible in an appropriate and reliable animal model. To date, the only animal model that resembles HPS in humans is the Syrian hamster model. Following infection with Andes virus, hamsters develop HPS-like disease which faithfully mimics the human condition with respect to incubation period and pathophysiology of disease. Perhaps most importantly, the sudden and rapid onset of severe respiratory distress observed in humans also occurs in hamsters. The last several years has seen an increase in studies utilizing the Andes virus hamster model which have provided unique insight into HPS pathogenesis as well as potential therapeutic and vaccine strategies to treat and prevent HPS. The purpose of this article is to review the current understanding of HPS disease progression in Syrian hamsters and discuss the suitability of utilizing this model to evaluate potential medical countermeasures against HPS. Copyright © 2012 Elsevier B.V. All rights reserved.

The Syrian hamster model of hantavirus pulmonary syndrome

PubMed Central

Safronetz, David; Ebihara, Hideki; Feldmann, Heinz; Hooper, Jay W.

2012-01-01

Hantavirus pulmonary syndrome (HPS) is a relatively rare, but frequently fatal disease associated with New World hantaviruses, most commonly Sin Nombre and Andes viruses in North and South America, respectively. It is characterized by fever and the sudden, rapid onset of severe respiratory distress and cardiogenic shock, which can be fatal in up to 50% of cases. Currently there are no approved antiviral therapies or vaccines for the treatment or prevention of HPS. A major obstacle in the development of effective medical countermeasures against highly pathogenic agents like the hantaviruses is recapitulating the human disease as closely as possible in an appropriate and reliable animal model. To date, the only animal model that resembles HPS in humans is the Syrian hamster model. Following infection with Andes virus, hamsters develop HPS-like disease which faithfully mimics the human condition with respect to incubation period and pathophysiology of disease. Perhaps most importantly, the sudden and rapid onset of severe respiratory distress observed in humans also occurs in hamsters. The last several years has seen an increase in studies utilizing the Andes virus hamster model which have provided unique insight into HPS pathogenesis as well as potential therapeutic and vaccine strategies to treat and prevent HPS. The purpose of this article is to review the current understanding of HPS disease progression in Syrian hamsters and discuss the suitability of utilizing this model to evaluate potential medical countermeasures against HPS. PMID:22705798

Nutritional stress enhances cell viability of odontoblast-like cells subjected to low level laser irradiation

NASA Astrophysics Data System (ADS)

Tagliani, M. M.; Oliveira, C. F.; Lins, E. M. M.; Kurachi, C.; Hebling, J.; Bagnato, V. S.; de Souza Costa, C. A.

2010-03-01

In spite of knowing that cells under stress are biostimulated by low level laser (LLL) irradiation, the ideal condition of stress to different cell lines has not yet been established. Consequently, the aim of the present in vitro study was to evaluate the effects of a defined parameter of LLL irradiation applied on stressed odontoblast-like pulp cells (MDPC-23). The cells were seeded (12500 cells/cm2) in wells of 24-well plates using complete culture medium (DMEM) and incubated for 24 hours. Then, the DMEM was replaced by a new medium with low concentrations (nutritional stress condition) of fetal bovine serum (FBS) giving rise to the following experimental groups: G1: 2% FBS; G2: 5% FBS; and G3: 10% FBS. The cells were irradiated three times with LLL in specific parameters (808±3 nm, 100 mW, 1.5 J/cm2) every 24 hours. No irradiation was carried out in groups G4 (2% FBS-Control), G5 (5% FBS-Control), and G6 (10% FBS-Control). For all groups, the cell metabolism (MTT assay) and morphology (SEM) was evaluated. The experimental groups showed enhanced cell metabolism and normal cell morphology regardless of FBS concentration. A slight increase in the cell metabolism was observed only in group G2. It was concluded that cell nutritional stress caused by reducing the concentration of FBS to 5% is the most suitable method to assess the biostimulation of LLL irradiated MDPC-23 cells.

Production of chimeric recombinant single domain antibody-green fluorescent fusion protein in Chinese hamster ovary cells.

PubMed

Bazl, M Rajabi; Rasaee, M J; Foruzandeh, M; Rahimpour, A; Kiani, J; Rahbarizadeh, F; Alirezapour, B; Mohammadi, M

2007-02-01

There is an increasing interest in the application of nanobodies such as VHH in the field of therapy and imaging. In the present study a stable genetically engineered cell line of Chinese hamster ovary (CHO) origin transfected using two sets of expression vectors was constructed in order to permit the cytoplasmic and extracellular expression of single domain antibody along with green fluorescent protein (GFP) as reporter gene. The quality of the constructs were examined both by the restriction map as well as sequence analysis. The gene transfection and protein expression was further examined by reverse transcription-polymerase chain reaction (RT-PCR). The transfected cells were grown in 200 microg/mL hygromycin containing media and the stable cell line obtained showed fluorescent activity for more than a period of 180 days. The production of fusion protein was also detected by fluorescent microscopy, fluorescent spectroscopy as well as by enzyme-linked immunosorbent assay (ELISA) analysis. This strategy allows a rapid production of recombinant fluobodies involving VHH, which can be used in various experiments such as imaging and detection in which a primary labeled antibody is required.

Inhibitory effects of Zengshengping fractions on DMBA-induced buccal pouch carcinogenesis in hamsters.

PubMed

Guan, Xiao-Bing; Sun, Zheng; Chen, Xiao-Xin; Wu, Hong-Ru; Zhang, Xin-Yan

2012-01-01

Zengshengping (ZSP) tablets had inhibitory effects on oral precancerous lesions by reducing the incidence of oral cancer. However, the severe liver toxicity caused by systemic administration of ZSP limits the long-term use of this anti-cancer drug. The purpose of this study was to evaluate the tumor inhibitory effects due to the topical application of extracts from ZSP, a Chinese herbal drug, on 7, 12-dimethlbenz(a)anthracene (DMBA) induced oral tumors in hamsters. The study also investigated the anti-cancer mechanisms of the ZSP extracts on oral carcinogenesis. DMBA (0.5%) was applied topically to the buccal pouches of Syrian golden hamsters (6 - 8 weeks old) three times per week for six weeks in order to induce the development of oral tumors. Different fractions of ZSP were either applied topically to the oral tumor lesions or fed orally at varying dosages to animals with oral tumors for 18 weeks. Tumor volume was measured by histopathological examination. Tumor cell proliferation was evaluated by counting BrdU labeled cells and by Western blotting for mitogen-activated protein kinase (MAPK) protein levels. The protein levels of apoptosis marker Caspase-3 and regulator Bcl-2 protein were also measured by Western blotting. Topical application of DMBA to the left pouch of hamsters induced oral tumor formation. Animals treated with DMBA showed a loss in body weight while animals treated with ZSP maintained normal body weights. Both the ZSP n-butanol fraction and water fraction significantly reduced tumor volume by 32.6% (P < 0.01) and 22.9% (P < 0.01) respectively. Topical application of ZSP also markedly decreased the BrdU-positive cell numbers in oral tumor lesions and reduced the expression level of MAPK. In addition, ZSP promoted tumor cell apoptosis by increasing Caspase-3 expression but decreasing Bcl-2 protein production. The n-butanol and water fractions of ZSP are effective at inhibiting tumor cell proliferation and stimulating apoptosis in oral cancer

Re-irradiation for head and neck squamous cell carcinoma.

PubMed

Benson, Rony; Giridhar, Prashant; Venkatesulu, Bhanu Prasad; Mallick, Supriya; Raza, Mohd Waseem; Rath, Goura Kishor

2017-03-01

Local recurrences after curative treatment have a potential for cure with salvage surgery or with re-irradiation. We reviewed the PubMed for articles published in English with key words squamous cell carcinoma, recurrent, re-irradiation, prognostic factors to find relevant articles describing prognostic factors, re-irradiation, and outcome for recurrent head and neck squamous cell carcinoma. Various factors including age, performance status, time for recurrence, previous radiation dose volume and site of recurrence, previous use of chemotherapy are all prognostic factors in recurrent head and neck squamous cell carcinoma. Surgery is feasible in very select subgroup of patients and must be done when feasible. Re-irradiation with the aid of modern sophisticated technology is safe and confers durable and clinically meaningful survival benefit. Re-irradiation in head and neck recurrent squamous cell carcinoma may provide an expected median survival of 10-12months. Chemotherapy may be added along with radiation in the recurrent setting. Treatment approaches may have to be personalized. Re surgery must be done in all patients in whom it is feasible. In patients in whom surgery is not feasible, re-irradiation must be evaluated as a therapeutic option especially in patients with limited volume recurrence. Copyright © 2016 National Cancer Institute, Cairo University. Production and hosting by Elsevier B.V. All rights reserved.

Endogenous ADP-ribosylation of elongation factor 2 in polyoma virus-transformed baby hamster kidney cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fendrick, J.L.; Iglewski, W.J.

1989-01-01

Polyoma virus-transformed baby hamster kidney (pyBHK) cells were cultured in medium containing ({sup 32}P)orthophosphate and 105 (vol/vol) fetal bovine serum. A {sup 32}P-labeled protein with an apparent molecular mass of 97 kDa was immunoprecipitated from cell lysates with antiserum to ADP-ribosylated elongation factor 2 (EF-2). The {sup 32}P labeling of the protein was enhanced by culturing cells in medium containing 2% serum instead of 10% serum. The {sup 32}P label was completely removed from the protein by treatment with snake venom phosphodiesterase and the digestion product was identified as ({sup 32}P)AMP, indicating the protein was mono-ADP-ribosylated. HPLC analysis of trypticmore » peptides of the {sup 32}P-labeled 97-kDa protein and purified EF-2, which was ADP-ribosylated in vitro with diphtheria toxin fragment A and ({sup 32}P)NAD, demonstrated an identical labeled peptide in the two proteins. The data strongly suggest that EF-2 was endogenously ADP-ribosylated in pyBHK cells. Maximum incorporation of radioactivity in EF-2 occurred by 12 hr and remained constant over the subsequent 12 hr. It was estimated that 30-35% of the EF-2 was ADP-ribosylated in cells cultured in medium containing 2% serum. When {sup 32}P-labeled cultures were incubated in medium containing unlabeled phosphate, the {sup 32}P label was lost from the EF-2 within 30 min.« less

Higher Initial DNA Damage and Persistent Cell Cycle Arrest after Carbon Ion Irradiation Compared to X-irradiation in Prostate and Colon Cancer Cells

PubMed Central

Suetens, Annelies; Konings, Katrien; Moreels, Marjan; Quintens, Roel; Verslegers, Mieke; Soors, Els; Tabury, Kevin; Grégoire, Vincent; Baatout, Sarah

2016-01-01

The use of charged-particle beams, such as carbon ions, is becoming a more and more attractive treatment option for cancer therapy. Given the precise absorbed dose-localization and an increased biological effectiveness, this form of therapy is much more advantageous compared to conventional radiotherapy, and is currently being used for treatment of specific cancer types. The high ballistic accuracy of particle beams deposits the maximal dose to the tumor, while damage to the surrounding healthy tissue is limited. In order to better understand the underlying mechanisms responsible for the increased biological effectiveness, we investigated the DNA damage and repair kinetics and cell cycle progression in two p53 mutant cell lines, more specifically a prostate (PC3) and colon (Caco-2) cancer cell line, after exposure to different radiation qualities. Cells were irradiated with various absorbed doses (0, 0.5, and 2 Gy) of accelerated 13C-ions at the Grand Accélérateur National d’Ions Lourds facility (Caen, France) or with X-rays (0, 0.1, 0.5, 1, 2, and 5 Gy). Microscopic analysis of DNA double-strand breaks showed dose-dependent increases in γ-H2AX foci numbers and foci occupancy after exposure to both types of irradiation, in both cell lines. However, 24 h after exposure, residual damage was more pronounced after lower doses of carbon ion irradiation compared to X-irradiation. Flow cytometric analysis showed that carbon ion irradiation induced a permanent G2/M arrest in PC3 cells at lower doses (2 Gy) compared to X-rays (5 Gy), while in Caco-2 cells the G2/M arrest was transient after irradiation with X-rays (2 and 5 Gy) but persistent after exposure to carbon ions (2 Gy). PMID:27148479

Progressive proliferative and dysplastic typhlocolitis in aging syrian hamsters naturally infected with Helicobacter spp.: a spontaneous model of inflammatory bowel disease.

PubMed

Nambiar, P R; Kirchain, S M; Courmier, K; Xu, S; Taylor, N S; Theve, E J; Patterson, M M; Fox, J G

2006-01-01

Helicobacter spp. have been implicated in a variety of gastrointestinal tract diseases, including peptic ulcer disease, gastric cancer, and inflammatory bowel disease (IBD), in humans and animals. Although most models of IBD are experimentally induced, spontaneous or natural models of IBD are rare. Herein, we describe a long-term study of chronic, progressive lesions that develop in the distal portion of the large bowel of unmanipulated Syrian hamsters naturally infected with Helicobacter spp. Twenty-four Syrian hamsters of three age groups (group A, 1 month [n = 4], group B, 7-12 months [n = 12], group C, 18-24 months [n = 12]), underwent complete postmortem examination. Results of microbial isolation and polymerase chain reaction and restriction fragment length polymorphism analyses confirmed the presence of Helicobacter spp. infection in the distal portion of the large bowel of all animals. Additionally, confounding pathogens, such as Clostridium difficile, Lawsonia intracellularis, and Giardia spp. that can cause proliferative enteritis, were absent in the hamsters of this study. Histopathologic scores for inflammation (P < 0.01), hyperplasia (P < 0.01), and dysplasia (P < 0.05) were significantly higher in the ileocecocolic (ICC) junction of animals in group C, relative to group A. Dysplastic lesions of various grades were detected in 5 of 11 hamsters in group C. Interestingly, the segment of the bowel that is usually colonized by Helicobacter spp. in hamsters had the most severe lesions. One hamster of group C developed a malignant fibrous histiocytoma, whereas another hamster developed a round cell sarcoma originating from the ICC junction. Thus, lesions in the distal portion of the large bowel of aging hamsters naturally colonized with Helicobacter spp. warrants developing the hamster as an animal model of IBD and potentially IBD-related cancer.

The Use of Transcription Terminators to Generate Transgenic Lines of Chinese Hamster Ovary Cells (CHO) with Stable and High Level of Reporter Gene Expression.

PubMed

Gasanov, N B; Toshchakov, S V; Georgiev, P G; Maksimenko, O G

2015-01-01

Mammalian cell lines are widely used to produce recombinant proteins. Stable transgenic cell lines usually contain many insertions of the expression vector in one genomic region. Transcription through transgene can be one of the reasons for target gene repression after prolonged cultivation of cell lines. In the present work, we used the known transcription terminators from the SV40 virus, as well as the human β- and γ-globin genes, to prevent transcription through transgene. The transcription terminators were shown to increase and stabilize the expression of the EGFP reporter gene in transgenic lines of Chinese hamster ovary (CHO) cells. Hence, transcription terminators can be used to create stable mammalian cells with a high and stable level of recombinant protein production.

Effect of ultrasonic irradiation on mammalian cells and chromosomes in vitro

NASA Technical Reports Server (NTRS)

Roseboro, J. A.; Buchanan, P.; Norman, A.; Stern, R.

1978-01-01

Human peripheral blood and HeLa cells were irradiated in vitro at the ultrasonic frequency of 65 kHz. The whole blood and HeLa cell suspensions were exposed to continuous and pulsed ultrasonic power levels of 0.12, 0.16, 0.72, 1.12 and 2.24 W for a period of one minute. The method of ultrasonic irradiation was carried out with the whole blood or HeLa cell suspensions coupled directly to a cylindrical transducer while heating of the cell suspensions in excess of 41 C was avoided. Irradiated and unirradiated peripheral blood lymphocyte chromosome cultures were prepared and scored for selected numerical and morphological aberrations. There was no significant difference in the frequency of chromosomal aberrations between irradiated and unirradiated cells.

Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset.

PubMed

Gualde, N; Goodwin, J S

1984-04-01

Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less [3H]thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced [3H]thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), and OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.

Chemopreventive effect of Toona sinensis leaf extract on 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch squamous cell carcinogenesis.

PubMed

Wang, Wen-Chen; Chen, Ching-Yi; Hsu, Hseng-Kuang; Lin, Li-Min; Chen, Yuk-Kwan

2016-10-01

Toona sinensis leaf extract (TSL) has been shown to have anti-tumor effects on cancer cell lines. This study aimed to investigate the chemopreventive potential and the underlying mechanism of TSL during 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. One hundred hamsters were divided into control (n=30), carcinogenic (n=20), preventive (n=42), and therapeutic (n=8) groups. The animals in carcinogenic and preventive groups were administered reverse osmosis water (carcinogenic group) or TSL (1g/kg bw) (preventive group) by gavage daily for 4 weeks, and their bilateral pouches were painted with a 0.5% DMBA solution for 4, 9, and 12 weeks. The animals in the therapeutic group were treated with DMBA for 12 weeks prior to TSL administration for 4 weeks. Expression levels of survivin, X chromosome-linked inhibitor of apoptosis (XIAP), proliferating cell nuclear antigen (PCNA), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) proteins were analyzed by immunohistochemistry. Apoptotic activity was examined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method, cytochrome C, and poly (ADP-ribose) polymerase (PARP). In the preventive group, the results showed significant decreases not only in the incidences of squamous cell carcinoma (SCC) (50%) and epithelial dysplasia (62.5%) but also in the tumor number, tumor volume, tumor burden, and the severity of dysplastic lesions. The down-regulation of survivin, XIAP, PCNA, iNOS, and COX-2 proteins and the increased apoptotic activity indicated anti-proliferative and apoptosis-inducing abilities of TSL on DMBA-induced HBP carcinogenesis. The results suggested that TSL might be a promising candidate for the prevention of oral cancer. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation with mTHPC of early squamous cell carcinomas of the cheek pouch mucosa of Golden Syrian hamsters as a model for clinical PDT of early cancers in the upper aerodigestive tract, the esophag

NASA Astrophysics Data System (ADS)

Glanzmann, Thomas M.; Theumann, Jean-Francois; Forrer, Martin; Braichotte, Daniel; Wagnieres, Georges A.; van den Bergh, Hubert; Andrejevic-Blant, Snezana; Savary, Jean-Francois; Monnier, Philippe

1995-03-01

Golden Syrian hamsters are evaluated as an animal model for light induced fluorescence (LIF) photodetection and phototherapy of early squamous cell carcinomas of the upper aerodigestive tract, the esophagus, and the traecheo-bronchial tree. Carcinomas of this type are induced on the hamster cheek pouch mucosa by the application of the carcinogen 7,12-DMBA. For phototherapeutic experiments on the animals we utilized meso-(tetrahydoxyphenyl) chlorin (mTHPC). This drug is currently in phase I and II clinical trials for ENT patients presenting superficial `early' squamous cell carcinomas. By means of LIF we measured in vivo the kinetics of the uptake and removal of mTHPC in the normal and tumoral cheek mucosa and in the skin. The photodynamic therapy (PDT) reaction of the tissue after excitation of the photosensitizer with laser light at 652 nm was studied. Both pharmacokinetics and PDT efficacy are compared between animal model and clinical results with special emphasis on selectivity between normal and tumoral mucosa. These first experiments show that this tumor model in the hamster cheek pouch seems to be suitable for testing new photosensitizers preceding their clinical application as well as for optimization of the multiple parameters of clinical PDT.

Effects of Nrf2 knockdown on the properties of irradiated cell conditioned medium from A549 human lung cancer cells.

PubMed

Yoshino, Hironori; Murakami, Kanna; Nawamaki, Mikoto; Kashiwakura, Ikuo

2018-05-01

The nuclear factor erythroid 2-related factor 2 (Nrf2) plays an important role in cellular defense against oxidative stress. Recent studies have demonstrated that Nrf2 is a useful target for cancer treatment, including radiation therapy. Ionizing radiation affects, not only the irradiated cells, but also the non-irradiated neighboring cells, and this effect is known as radiation-induced bystander effect. Upon exposure to radiation, the irradiated cells transmit signals to the non-irradiated cells via gap junctions or soluble factors. These signals in turn cause biological effects, such as a decrease in the clonogenic potential and cell death, in the non-irradiated neighboring cells. Nrf2 inhibition enhances cellular radiosensitivity. However, whether this modification of radiosensitivity by Nrf2 inhibition affects the radiation-induced bystander effects is unknown. In this study, we prepared an Nrf2 knockdown human lung cancer cell A549 and investigated whether the effects of irradiated cell conditioned medium (ICCM) on cell growth and cell death induction of non-irradiated cells vary depending on the Nrf2 knockdown. We found that Nrf2 knockdown resulted in a decrease in the cell growth and an increase in the radiosensitivity of A549 cells. When non-irradiated A549 cells were transfected with control siRNA and treated with ICCM, no significant difference was observed in the cell growth and proportion of Annexin V + dead cells between ICCM from non-irradiated cells and that from 2 or 8 Gy-irradiated cells. Similarly, no significant difference was observed in the cell growth and cell death induction upon treatment with ICCM in the Nrf2 knockdown A549 cells. Taken together, these results suggest that Nrf2 knockdown decreases cell growth and enhances the radiosensitivity of A549 cells; however, it does not alter the effect of ICCM on cell growth.

Topical photosan-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premaligant lesions: an in vivo study

NASA Astrophysics Data System (ADS)

Hsu, Yih-Chih; Chiang, Chun-Pin; Chen, Jian Wen; Chen, Ying-Ru; Lee, Jeng-Woei

2010-02-01

One of the best strategies to prevent the occurrence of oral cancer is to eliminate oral precancers and block their further malignant transformation. Previous studies showed that photosan-mediated photodynamic therapy (photosan-PDT) is very effective for human head and neck cancers. To avoid the systemic photodynamic toxicity of photosan, this study was designed to use a topical photosan-PDT for treatment of DMBA-induced hamster buccal pouch precancerous lesions. Twelve 10-week-old male Syrian golden hamsters were used in this study. DMBA was applied to the left buccal pouches thrice a week for 8 to 10 weeks and mineral oil was painted on the right buccal pouches thrice a week for 8 to 10 weeks as the normal controls. Six hamsters were euthanized for tissue harvest. Precancerous lesions of moderate to severe dysplasia were consistently induced and proven by histological examination. These induced precancerous lesions in the remaining 6 hamsters were used for testing the efficacy of topical photosan-PDT. Before PDT, fluorescence spectroscopy was used to determine when protoporphyrine IX (PpIX) reached its peak level in the lesional epithelial cells after topical application of photosan-gel. We found that PpIX reached its peak level in precancerous lesions about 13.5 min after topical application of photosan-gel. The precancerous lesions in 4 hamsters were treated with topical photosan-PDT using the 635-nm LED light once or twice a week. Complete regression of the precancerous lesions was found after 2-4 PDT treatments by visual and histological examination. Our findings indicate that topical photosan-PDT is a very effective treatment modality for DMBA-induced hamster buccal pouch precancerous lesions.

Metabolic influences on circadian rhythmicity in Siberian and Syrian hamsters exposed to long photoperiods.

PubMed

Challet, E; Kolker, D E; Turek, F W

2000-01-01

Calorie restriction and other situations of reduced glucose availability in rodents alter the entraining effects of light on the circadian pacemaker located in the suprachiasmatic nuclei. Siberian and Syrian hamsters are photoperiodic species that are sexually active when exposed to long summer-like photoperiods, while both species show opposite changes in body mass when transferred from long to short or short to long days. Because metabolic cues may fine tune the photoperiodic responses via the suprachiasmatic nuclei, we tested whether timed calorie restriction can alter the photic synchronization of the light-entrainable pacemaker in these two hamster species exposed to long photoperiods. Siberian and Syrian hamsters were exposed to 16 h:8 h light:dark cycles and received daily hypocaloric (75% of daily food intake) or normocaloric diet (100% of daily food intake) 4 h after light onset. Four weeks later, hamsters were transferred to constant darkness and fed ad libitum. The onset of the nocturnal pattern of locomotor activity was phase advanced by 1.5 h in calorie-restricted Siberian hamsters, but not in Syrian hamsters. The lack of phase change in calorie-restricted Syrian hamsters was also observed in individuals exposed to 14 h:10 h dim light:dark cycles and fed with lower hypocaloric food (i.e. 60% of daily food intake) 2 h after light onset. Moreover, in hamsters housed in constant darkness and fed ad lib., light-induced phase shifts of the locomotor activity in Siberian hamsters, but not in Syrian hamsters were significantly reduced when glucose utilization was blocked by pretreatment with 500 mg/kg i.p. 2-deoxy-D-glucose. Taken together, these results show that the photic synchronization of the light-entrainable pacemaker can be modulated by metabolic cues in Siberian hamsters, but not in Syrian hamsters maintained on long days.

A lethal disease model for New World hantaviruses using immunosuppressed Syrian hamsters.

PubMed

Vergote, Valentijn; Laenen, Lies; Vanmechelen, Bert; Van Ranst, Marc; Verbeken, Erik; Hooper, Jay W; Maes, Piet

2017-10-01

Hantavirus, the hemorrhagic causative agent of two clinical diseases, is found worldwide with variation in severity, incidence and mortality. The most lethal hantaviruses are found on the American continent where the most prevalent viruses like Andes virus and Sin Nombre virus are known to cause hantavirus pulmonary syndrome. New World hantavirus infection of immunocompetent hamsters results in an asymptomatic infection except for Andes virus and Maporal virus; the only hantaviruses causing a lethal disease in immunocompetent Syrian hamsters mimicking hantavirus pulmonary syndrome in humans. Hamsters, immunosuppressed with dexamethasone and cyclophosphamide, were infected intramuscularly with different New World hantavirus strains (Bayou virus, Black Creek Canal virus, Caño Delgadito virus, Choclo virus, Laguna Negra virus, and Maporal virus). In the present study, we show that immunosuppression of hamsters followed by infection with a New World hantavirus results in an acute disease that precisely mimics both hantavirus disease in humans and Andes virus infection of hamsters. Infected hamsters showed specific clinical signs of disease and moreover, histological analysis of lung tissue showed signs of pulmonary edema and inflammation within alveolar septa. In this study, we were able to infect immunosuppressed hamsters with different New World hantaviruses reaching a lethal outcome with signs of disease mimicking human disease.

Comparative viability of unirradiated and gamma irradiated bacterial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maxcy, R.B.

1977-01-01

Gamma radiation injured Escherichia coli, Salmonella typhimurium, and Moraxella sp. were studied under various environmental stresses to determine their fate relative to the parent population. Irradiated cultures formed smaller colonies on surface plates with fewer cells per colony. Unirradiated cultures had a shorter lag phase than irradiated cultures in broth and duration of lag increased as a result of increasing the radiation dose. Repeated irradiation and subculture progressively retarded growth rate. Multiple radiation of highly resistant Moraxella sp. showed radiation injured cells to be more sensitive than uninjured cells. With the three species studied, irradiation raised the lower limits ofmore » growth temperature, increased the sensitivity to freezing and thawing, and increased the susceptibility to lowered water activity. This work indicated that the production of a bizarre, resistant strain of bacteria through recycling in a food processing operation is highly unlikely.« less

Evaluation of formalin-inactivated Clostridium difficile vaccines administered by parenteral and mucosal routes of immunization in hamsters.

PubMed Central

Torres, J F; Lyerly, D M; Hill, J E; Monath, T P

1995-01-01

Clostridium difficile produces toxins that cause inflammation, necrosis, and fluid in the intestine and is the most important cause of nosocomial antibiotic-associated diarrhea and colitis. We evaluated C. difficile antigens as vaccines to protect against systemic and intestinal disease in a hamster model of clindamycin colitis. Formalin-inactivated culture filtrates from a highly toxigenic strain were administered by mucosal routes (intranasal, intragastric, and rectal) with cholera toxin as a mucosal adjuvant. A preparation of culture filtrate and killed whole cells was also tested rectally. The toxoid was also tested parenterally (subcutaneously and intraperitoneally) and by a combination of three intranasal immunizations followed by a combined intranasal-intraperitoneal boost. Serum antibodies against toxins A and B and whole-cell antigen were measured by enzyme-linked immunosorbent assay, neutralization of cytotoxic activity, and bacterial agglutination. The two rectal immunization regimens induced low antibody responses and protected only 20% of hamsters against death and 0% against diarrhea. The intragastric regimen induced high antibody responses but low protection, 40% against death and 0% against diarrhea. Hamsters immunized by the intranasal, intraperitoneal, and subcutaneous routes were 100% protected against death and partially protected (40, 40, and 20%, respectively) against diarrhea. Among the latter groups, intraperitoneally immunized animals had the highest serum anticytotoxic activity and the highest agglutinating antibody responses. Hamsters immunized intranasally and revaccinated intraperitoneally were 100% protected against both death and diarrhea. Protection against death and diarrhea correlated with antibody responses to all antigens tested. The results indicate that optimal protection against C. difficile disease can be achieved with combined parenteral and mucosal immunization. PMID:7591115

Mechanisms of taste bud cell loss after head and neck irradiation

PubMed Central

Nguyen, Ha M.; Reyland, Mary E.; Barlow, Linda A.

2012-01-01

Taste loss in human patients following radiotherapy for head and neck cancer is a common and significant problem, but the cellular mechanisms underlying this loss are not understood. Taste stimuli are transduced by receptor cells within taste buds, and like epidermal cells, taste cells are regularly replaced throughout adult life. This renewal relies on a progenitor cells adjacent to taste buds, which continually supply new cells to each bud. Here we treated adult mice with a single 8 Gy dose of X-ray irradiation to the head and neck, and analyzed taste epithelium at 1–21 days post-irradiation (dpi). We found irradiation targets the taste progenitor cells, which undergo cell cycle arrest (1–3 dpi) and apoptosis (within 1 dpi). Taste progenitors resume proliferation at 5–7 dpi, with the proportion of cells in S and M phase exceeding control levels at 5–6 and 6 dpi, respectively, suggesting that proliferation is accelerated and/or synchronized following radiation damage. Using BrdU birthdating to identify newborn cells, we found that the decreased proliferation following irradiation reduces the influx of cells at 1–2 dpi, while the robust proliferation detected at 6 dpi accelerates entry of new cells into taste buds. By contrast, the number of differentiated taste cells was not significantly reduced until 7 dpi. These data suggest a model where continued natural taste cell death, paired with temporary interruption of cell replacement underlies taste loss after irradiation. PMID:22399770

Foodborne transmission of nipah virus in Syrian hamsters.

PubMed

de Wit, Emmie; Prescott, Joseph; Falzarano, Darryl; Bushmaker, Trenton; Scott, Dana; Feldmann, Heinz; Munster, Vincent J

2014-03-01

Since 2001, outbreaks of Nipah virus have occurred almost every year in Bangladesh with high case-fatality rates. Epidemiological data suggest that in Bangladesh, Nipah virus is transmitted from the natural reservoir, fruit bats, to humans via consumption of date palm sap contaminated by bats, with subsequent human-to-human transmission. To experimentally investigate this epidemiological association between drinking of date palm sap and human cases of Nipah virus infection, we determined the viability of Nipah virus (strain Bangladesh/200401066) in artificial palm sap. At 22°C virus titers remained stable for at least 7 days, thus potentially allowing food-borne transmission. Next, we modeled food-borne Nipah virus infection by supplying Syrian hamsters with artificial palm sap containing Nipah virus. Drinking of 5×10⁸ TCID₅₀ of Nipah virus resulted in neurological disease in 5 out of 8 hamsters, indicating that food-borne transmission of Nipah virus can indeed occur. In comparison, intranasal (i.n.) inoculation with the same dose of Nipah virus resulted in lethal respiratory disease in all animals. In animals infected with Nipah virus via drinking, virus was detected in respiratory tissues rather than in the intestinal tract. Using fluorescently labeled Nipah virus particles, we showed that during drinking, a substantial amount of virus is deposited in the lungs, explaining the replication of Nipah virus in the respiratory tract of these hamsters. Besides the ability of Nipah virus to infect hamsters via the drinking route, Syrian hamsters infected via that route transmitted the virus through direct contact with naïve hamsters in 2 out of 24 transmission pairs. Although these findings do not directly prove that date palm sap contaminated with Nipah virus by bats is the origin of Nipah virus outbreaks in Bangladesh, they provide the first experimental support for this hypothesis. Understanding the Nipah virus transmission cycle is essential for preventing

Foodborne Transmission of Nipah Virus in Syrian Hamsters

PubMed Central

de Wit, Emmie; Prescott, Joseph; Falzarano, Darryl; Bushmaker, Trenton; Scott, Dana; Feldmann, Heinz; Munster, Vincent J.

2014-01-01

Since 2001, outbreaks of Nipah virus have occurred almost every year in Bangladesh with high case-fatality rates. Epidemiological data suggest that in Bangladesh, Nipah virus is transmitted from the natural reservoir, fruit bats, to humans via consumption of date palm sap contaminated by bats, with subsequent human-to-human transmission. To experimentally investigate this epidemiological association between drinking of date palm sap and human cases of Nipah virus infection, we determined the viability of Nipah virus (strain Bangladesh/200401066) in artificial palm sap. At 22°C virus titers remained stable for at least 7 days, thus potentially allowing food-borne transmission. Next, we modeled food-borne Nipah virus infection by supplying Syrian hamsters with artificial palm sap containing Nipah virus. Drinking of 5×108 TCID50 of Nipah virus resulted in neurological disease in 5 out of 8 hamsters, indicating that food-borne transmission of Nipah virus can indeed occur. In comparison, intranasal (i.n.) inoculation with the same dose of Nipah virus resulted in lethal respiratory disease in all animals. In animals infected with Nipah virus via drinking, virus was detected in respiratory tissues rather than in the intestinal tract. Using fluorescently labeled Nipah virus particles, we showed that during drinking, a substantial amount of virus is deposited in the lungs, explaining the replication of Nipah virus in the respiratory tract of these hamsters. Besides the ability of Nipah virus to infect hamsters via the drinking route, Syrian hamsters infected via that route transmitted the virus through direct contact with naïve hamsters in 2 out of 24 transmission pairs. Although these findings do not directly prove that date palm sap contaminated with Nipah virus by bats is the origin of Nipah virus outbreaks in Bangladesh, they provide the first experimental support for this hypothesis. Understanding the Nipah virus transmission cycle is essential for preventing and

Effect of diisopropanolamine upon choline uptake and phospholipid synthesis in Chinese hamster ovary cells.

PubMed

Stott, W T; Kleinert, K M

2008-02-01

Aminoalcohols differ in mammalian toxicity at least in part based upon their ability to alter the metabolism of phospholipids and to cause depletion of the essential nutrient choline in animals. This study examined the incorporation of diisopropanolamine (DIPA) into phospholipids (PLs) and effects of DIPA upon choline uptake and phospholipid synthesis in Chinese hamster ovary (CHO) cells. Results were compared to those of a related secondary alcohol amine, diethanolamine (DEA), whose systemic toxicity is closely associated with its metabolic incorporation into PLs and depletion of choline pools. DIPA caused a dose-related inhibition of (3)H-choline uptake by CHO cells that was approximately 3-4 fold less potent, based upon an IC50, than that reported for DEA. DIPA, in contrast to DEA, did not cause changes in the synthesis rates of (33)P-phosphatidylethanolamine, (33)P-phosphatidylcholine or (33)P-sphingomyelin at either non-toxic or moderately toxic concentrations. Only approximately 0.004%, of administered (14)C-DIPA was metabolically incorporated into PLs, over 30-fold less than the incorporation of (14)C-DEA under similar conditions. Overall, these data and previous pharmacokinetic and toxicity data obtained in vivo suggests that DIPA is distinct from DEA and lacks significant choline and PL metabolism related toxicity in animals.

MSH3 deficiency is not sufficient for a mutator phenotype in Chinese hamster ovary cells.

PubMed

Hinz, J M; Meuth, M

1999-02-01

In the yeast Saccharomyces cerevisiae, the mutS homolog protein products MSH3 and MSH6, each in cooperation with MSH2, play well-defined and specific roles in the repair of DNA mismatches and nucleotide loops. The discrete functions of the human homologs hMSH3 and hMSH6 are less clear and current evidence suggests that the substrate specificity of these proteins may be less strict. To determine the role of MSH3 in mammalian mismatch repair, we employed MSH3-deficient Chinese hamster ovary (CHO) cell lines. No significant changes in mutation rate were detected in the MSH3-deficient strain and there were no differences in sensitivity to DNA-damaging agents. Further analysis of hprt mutants did not show a MSH3-dependent shift in the mutant spectrum. Interestingly, thorough examination of four dinucleotide microsatellite regions revealed instability at only one locus in one of the MSH3-deficient cell lines. These data support the idea of a high degree of redundancy in the function of the MutS homologs MSH3 and MSH6, at least with respect to the control of microsatellite instability.

Proton beam irradiation inhibits the migration of melanoma cells.

PubMed

Jasińska-Konior, Katarzyna; Pochylczuk, Katarzyna; Czajka, Elżbieta; Michalik, Marta; Romanowska-Dixon, Bożena; Swakoń, Jan; Urbańska, Krystyna; Elas, Martyna

2017-01-01

In recent years experimental data have indicated that low-energy proton beam radiation might induce a difference in cellular migration in comparison to photons. We therefore set out to compare the effect of proton beam irradiation and X-rays on the survival and long-term migratory properties of two cell lines: uveal melanoma Mel270 and skin melanoma BLM. Cells treated with either proton beam or X-rays were analyzed for their survival using clonogenic assay and MTT test. Long-term migratory properties were assessed with time-lapse monitoring of individual cell movements, wound test and transpore migration, while the expression of the related proteins was measured with western blot. Exposure to proton beam and X-rays led to similar survival but the quality of the cell colonies was markedly different. More paraclones with a low proliferative activity and fewer highly-proliferative holoclones were found after proton beam irradiation in comparison to X-rays. At 20 or 40 days post-irradiation, migratory capacity was decreased more by proton beam than by X-rays. The beta-1-integrin level was decreased in Mel270 cells after both types of radiation, while vimentin, a marker of EMT, was increased in BLM cells only. We conclude that proton beam irradiation induced long-term inhibition of cellular motility, as well as changes in the level of beta-1 integrin and vimentin. If confirmed, the change in the quality, but not in the number of colonies after proton beam irradiation might favor tumor growth inhibition after fractionated proton therapy.

Phosphatidylserine biosynthesis in cultured Chinese hamster ovary cells. II. Isolation and characterization of phosphatidylserine auxotrophs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuge, O.; Nishijima, M.; Akamatsu, Y.

1986-05-05

Chinese hamster ovary (CHO) cell mutants that required exogenously added phosphatidylserine for cell growth were isolated by using the replica technique with polyester cloth, and three such mutants were characterized. Labeling experiments on intact cells with /sup 32/Pi and L-(U-/sup 14/C)serine revealed that a phosphatidylserine auxotroph, designated as PSA-3, was strikingly defective in phosphatidylserine biosynthesis. When cells were grown for 2 days without phosphatidylserine, the phosphatidylserine content of PSA-3 was about one-third of that of the parent. In extracts of the mutant, the enzymatic activity of the base-exchange reaction of phospholipids with serine producing phosphatidylserine was reduced to 33% ofmore » that in the parent; in addition, the activities of base-exchange reactions of phospholipids with choline and ethanolamine in the mutant were also reduced to 1 and 45% of those in the parent, respectively. Furthermore, it was demonstrated that the serine-exchange activity in the parent was inhibited approximately 60% when choline was added to the reaction mixture whereas that in the mutant was not significantly affected. From the results presented here, we conclude the following. There are at least two kinds of serine-exchange enzymes in CHO cells; one (serine-exchange enzyme I) can catalyze the base-exchange reactions of phospholipids with serine, choline, and ethanolamine while the other (serine-exchange enzyme II) does not use the choline as a substrate. Serine-exchange enzyme I, in which mutant PSA-3 is defective, plays a major role in phosphatidylserine biosynthesis in CHO cells. Serine-exchange enzyme I is essential for the growth of CHO cells.« less

Genetic changes in mammalian cells transformed by helium ions

NASA Astrophysics Data System (ADS)

Durante, M.; Grossi, G.; Yang, T. C.; Roots, R.

Midterm Syrian Hamster embryo (SHE) cells were employed to study high LET-radiation induced tumorigenesis. Normal SHE cells (secondary passage) were irradiated with accelerated helium ions at an incident energy of 22 MeV/u (9-10 keV/μm). Transformed clones were isolated after growth in soft agar of cells obtained from the foci of the initial monolayer plated postirradiation. To study the progression process of malignant transformation, the transformed clones were followed by monolayer subculturing for prolonged periods of time. Subsequently, neoplasia tests in nude mice were done. In this work, however, we have focused on karyotypic changes in the banding patterns of the chromosomes during the early part of the progressive process of cell transformation for helium ion-induced transformed cells.

Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gualde, N.; Goodwin, J.S.

1984-04-01

Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less (/sup 3/H)thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced (/sup 3/H)thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), andmore » OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.« less

Senescence of nickel-transformed cells by an X chromosome: Possible epigenetic control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, C.B.; Xin Wei Wang; Bhamra, R.K.

1991-02-15

Transfer of a normal Chinese hamster X chromosome (carried in a mouse A9 donor cell line) to a nickel-transformed Chinese hamster cell line with an Xq chromosome deletion resulted in senescense of these previously immortal cells. At early passages of the A9/CX donor cells, the hamster X chromosome was highly active, inducing senescence in 100% of the colonies obtained after its transfer into the nickel-transformed cells. However, senescence was reduced to 50% when Chinese hamster X chromosomes were transferred from later passage A9 cells. Full senescing activity of the intact hamster X chromosome was restored by treatment of the donormore » mouse cells with 5-azacytidine, which induced demethylation of DMA. These results suggest that a senescence gene or genes, which may be located on the Chinese hamster X chromosome, can be regulated by DNA methylation, and that escape from senescence and possibly loss of tumor suppressor gene activity can occur by epigenetic mechanisms.« less

Retinal ganglion cell projections to the hamster suprachiasmatic nucleus, intergeniculate leaflet, and visual midbrain: bifurcation and melanopsin immunoreactivity

NASA Technical Reports Server (NTRS)

Morin, Lawrence P.; Blanchard, Jane H.; Provencio, Ignacio

2003-01-01

The circadian clock in the suprachiasmatic nucleus (SCN) receives direct retinal input via the retinohypothalamic tract (RHT), and the retinal ganglion cells contributing to this projection may be specialized with respect to direct regulation of the circadian clock. However, some ganglion cells forming the RHT bifurcate, sending axon collaterals to the intergeniculate leaflet (IGL) through which light has secondary access to the circadian clock. The present studies provide a more extensive examination of ganglion cell bifurcation and evaluate whether ganglion cells projecting to several subcortical visual nuclei contain melanopsin, a putative ganglion cell photopigment. The results showed that retinal ganglion cells projecting to the SCN send collaterals to the IGL, olivary pretectal nucleus, and superior colliculus, among other places. Melanopsin-immunoreactive (IR) ganglion cells are present in the hamster retina, and some of these cells project to the SCN, IGL, olivary pretectal nucleus, or superior colliculus. Triple-label analysis showed that melanopsin-IR cells bifurcate and project bilaterally to each SCN, but not to the other visual nuclei evaluated. The melanopsin-IR cells have photoreceptive characteristics optimal for circadian rhythm regulation. However, the presence of moderately widespread bifurcation among ganglion cells projecting to the SCN, and projection by melanopsin-IR cells to locations distinct from the SCN and without known rhythm function, suggest that this ganglion cell type is generalized, rather than specialized, with respect to the conveyance of photic information to the brain. Copyright 2003 Wiley-Liss, Inc.

Cell migration under ultrasound irradiations in micrometer scale

NASA Astrophysics Data System (ADS)

Murakami, Shinya; Otsuka, Yo; Oshima, Yusuke; Hikita, Atsuhiko; Mitsui, Toshiyuki

2013-03-01

Cell movements, migration play an important role in many physiological processes including cell proliferation and differentiation. C2C12, a line of mouse myoblasts is known to differentiate into osteoblast under appropriate conditions. Therefore, C2C12 cells can be chosen for the differentiation studies. However, the movement of the C2C12's has not been fully investigated although the movements may provide a better understanding of the healing processes of bone repair, regeneration and differentiation. In addition, low intensity ultrasound has been thought and used to promote bone fracture healing although the microscopic mechanism of this healing is not well understood. As a first step, we have investigated single cell migration of C2C12 under optical microscopy with and without ultrasound irradiations. The ultrasound is irradiated from an apex of a sharp needle. The frequency is 1.5 MHz and the power intensity is near 24 mW/cm2. These values were similar to the ultrasound treatment values. In this conference, we will show the influence of the ultrasound irradiation on the cell movement by plotting the mean squared displacement and the velocity autocorrelation function as a function of time.

Experimental study on rat NK cell activity improvement by laser acupoint irradiation

NASA Astrophysics Data System (ADS)

Yang, Dongxiao; Chen, Xiufeng; Ruan, Buqing; Yang, Feng

1998-08-01

To study the improvement of the natural killer (NK) cell activity by semiconductor laser acupoint irradiation, rats were used in this experiment and were injected immunosuppressant in their abdomen. The immunoassay was made after the surface irradiation and inner irradiation at Baihui point by semiconductor laser. The NK cell activity is an important index of immunologic function. The results showed that the NK cell activity after laser acupoint irradiation was enhanced. This enhancement is relatively important in the clinical therapy of tumor.

Cell irradiation setup and dosimetry for radiobiological studies at ELBE

NASA Astrophysics Data System (ADS)

Zeil, K.; Beyreuther, E.; Lessmann, E.; Wagner, W.; Pawelke, J.

2009-07-01

The radiation source ELBE delivers different types of secondary radiation, which is used for cell irradiation studies in radiobiological research. Thereby an important issue is the determination of the biological effectiveness of photon radiation as a function of photon energy by using low-energetic, monochromatic channeling radiation (10-100 keV) and high-energetic bremsstrahlung (up to 40 MV). Radiobiological studies at the research facility ELBE demand special technical and dosimetric prerequisites. Therefore, a cell irradiation system (CIS) has been designed, constructed and installed at the beam line. The CIS allows automatic irradiation of a larger cell sample number and the compensation of spatial inhomogeneity of the dose distribution within the beam spot. The recently introduced GafChromic ® EBT radiochromic film model has been used to verify the cell irradiation dose deposition achieving a dose uncertainty of <5%. Both, the installed cell irradiation system and the developed dosimetric procedure based on the use of the EBT film have been experimentally tested at ELBE. The biological effectiveness of 34 MV bremsstrahlung with respect to 200 kV X-rays from a conventional X-ray tube has been determined. An RBE value of 0.75 has been measured in good agreement with literature.

Natural Immunity to Ebola Virus in the Syrian Hamster Requires Antibody Responses.

PubMed

Prescott, Joseph; Falzarano, Darryl; Feldmann, Heinz

2015-10-01

Most ebolaviruses can cause severe disease in humans and other primates, with high case fatality rates during human outbreaks. Although these viruses have been studied for almost 4 decades, little is know regarding the mechanisms by which they cause disease and what is important for protection or treatment after infection. Because of the sporadic nature of the outbreaks and difficulties accessing the populations affected by ebolaviruses, little is also known about what constitutes an appropriate immune response to infection in humans that survive infection. Such knowledge would allow a targeted approach to therapies. In contrast to humans, rodents are protected from disease on infection with ebolaviruses, although adapted versions of some of the viruses are lethal in mice, hamsters and guinea pigs. Using the recently described hamster model, along with T-cell depletion strategies, we show that CD4(+) T cells are required for natural immunity to Ebola virus infection and that CD4-dependent antibody responses are required for immunity in this model. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Nipah virus transmission in a hamster model.

PubMed

de Wit, Emmie; Bushmaker, Trenton; Scott, Dana; Feldmann, Heinz; Munster, Vincent J

2011-12-01

Based on epidemiological data, it is believed that human-to-human transmission plays an important role in Nipah virus outbreaks. No experimental data are currently available on the potential routes of human-to-human transmission of Nipah virus. In a first dose-finding experiment in Syrian hamsters, it was shown that Nipah virus was predominantly shed via the respiratory tract within nasal and oropharyngeal secretions. Although Nipah viral RNA was detected in urogenital and rectal swabs, no infectious virus was recovered from these samples, suggesting no viable virus was shed via these routes. In addition, hamsters inoculated with high doses shed significantly higher amounts of viable Nipah virus particles in comparison with hamsters infected with lower inoculum doses. Using the highest inoculum dose, three potential routes of Nipah virus transmission were investigated in the hamster model: transmission via fomites, transmission via direct contact and transmission via aerosols. It was demonstrated that Nipah virus is transmitted efficiently via direct contact and inefficiently via fomites, but not via aerosols. These findings are in line with epidemiological data which suggest that direct contact with nasal and oropharyngeal secretions of Nipah virus infected individuals resulted in greater risk of Nipah virus infection. The data provide new and much-needed insights into the modes and efficiency of Nipah virus transmission and have important public health implications with regards to the risk assessment and management of future Nipah virus outbreaks.

Nipah Virus Transmission in a Hamster Model

PubMed Central

de Wit, Emmie; Bushmaker, Trenton; Scott, Dana; Feldmann, Heinz; Munster, Vincent J.

2011-01-01

Based on epidemiological data, it is believed that human-to-human transmission plays an important role in Nipah virus outbreaks. No experimental data are currently available on the potential routes of human-to-human transmission of Nipah virus. In a first dose-finding experiment in Syrian hamsters, it was shown that Nipah virus was predominantly shed via the respiratory tract within nasal and oropharyngeal secretions. Although Nipah viral RNA was detected in urogenital and rectal swabs, no infectious virus was recovered from these samples, suggesting no viable virus was shed via these routes. In addition, hamsters inoculated with high doses shed significantly higher amounts of viable Nipah virus particles in comparison with hamsters infected with lower inoculum doses. Using the highest inoculum dose, three potential routes of Nipah virus transmission were investigated in the hamster model: transmission via fomites, transmission via direct contact and transmission via aerosols. It was demonstrated that Nipah virus is transmitted efficiently via direct contact and inefficiently via fomites, but not via aerosols. These findings are in line with epidemiological data which suggest that direct contact with nasal and oropharyngeal secretions of Nipah virus infected individuals resulted in greater risk of Nipah virus infection. The data provide new and much-needed insights into the modes and efficiency of Nipah virus transmission and have important public health implications with regards to the risk assessment and management of future Nipah virus outbreaks. PMID:22180802

Expression of FSH receptor in the hamster ovary during perinatal development

PubMed Central

Chakraborty, Prabuddha; Roy, Shyamal K.

2014-01-01

FSH plays an important role in ovarian follicular development, and it functions via the G-protein coupled FSH receptor. The objectives of the present study were to determine if full-length FSHR mRNA and corresponding protein were expressed in fetal through postnatal hamster ovaries to explain the FSH-induced primordial follicle formation, and if FSH or estrogen (E) would affect the expression. A full-length and two alternately spliced FSHR transcripts were expressed from E14 through P20. The level of the full-length FSHR mRNA increased markedly through P7 before stabilizing at a lower level with the formation and activation of primordial follicles. A predicted 87kDa FSHR protein band was detected in fetal through P4 ovaries, but additional bands appeared as ovary developed. FSHR immunosignal was present in undifferentiated somatic cells and oocytes in early postnatal ovaries, but was granulosa cells specific after follicles formed. Both eCG and E significantly up-regulated full-length FSHR mRNA levels. Therefore, FSHR is expressed in the hamster ovary from the fetal life to account for FSH-induced primordial follicle formation and cAMP production. Further, FSH or E regulates the receptor expression. PMID:25462586

Inhibition of EGFR nuclear shuttling decreases irradiation resistance in HeLa cells.

PubMed

Wei, Hong; Zhu, Zijie; Lu, Longtao

2017-01-01

Cervical cancer is a leading cause of mortality in women worldwide. The resistance to irradiation at the advanced stage is the main reason for the poor prognosis and high mortality. This work aims to elucidate the molecular mechanism underlying the radio-resistance. In this study, we determined the pEGFR-T654 and pDNA-PK-T2609 expression level changes in irradiated HeLa cells treated with T654 peptide, a nuclear localization signal (NLS) inhibitor, to inhibit EGFR nuclear transport. Cell viability, cell cycle and migratory capacity were analyzed. Xenograft animal model was used to evaluate the effect of EGFR nuclear transport inhibition on the tumor growth in vivo. The enhanced translocation of nuclear EGFR in the irradiated HeLa cells correlated with the increasing level of pEGFR-T654 and pDNA-PK-T2609. Inhibition of EGFR nuclear translocation by NLS peptide inhibitor attenuated DNA damage repair in the irradiated HeLa cells, decreased cell viability and promoted cell death through arrest at G0 phase. NLS peptide inhibitor impaired the migratory capacity of irradiated HeLa cells, and negatively affected tumorigenesis in xenograft mice. This work puts forward a potential molecular mechanism of the irradiation resistance in cervical cancer cells, providing a promising direction towards an efficient therapy of cervical cancer.

Irradiated fibroblasts promote epithelial–mesenchymal transition and HDGF expression of esophageal squamous cell carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bao, Ci-Hang; Wang, Xin-Tong; Ma, Wei

2015-03-06

Recent evidence suggested that nonirradiated cancer-associated fibroblasts (CAFs) promoted aggressive phenotypes of cancer cells through epithelial–mesenchymal transition (EMT). Hepatoma-derived growth factor (HDGF) is a radiosensitive gene of esophageal squamous cell carcinoma (ESCC). This study aimed to investigate the effect of irradiated fibroblasts on EMT and HDGF expression of ESCC. Our study demonstrated that coculture with nonirradiated fibroblasts significantly increased the invasive ability of ESCC cells and the increased invasiveness was further accelerated when they were cocultured with irradiated fibroblasts. Scattering of ESCC cells was also accelerated by the supernatant from irradiated fibroblasts. Exposure of ESCC cells to supernatant from irradiatedmore » fibroblasts resulted in decreased E-cadherin, increased vimentin in vitro and β-catenin was demonstrated to localize to the nucleus in tumor cells with irradiated fibroblasts in vivo models. The expression of HDGF and β-catenin were increased in both fibroblasts and ESCC cells of irradiated group in vitro and in vivo models. Interestingly, the tumor cells adjoining the stromal fibroblasts displayed strong nuclear HDGF immunoreactivity, which suggested the occurrence of a paracrine effect of fibroblasts on HDGF expression. These data suggested that irradiated fibroblasts promoted invasion, growth, EMT and HDGF expression of ESCC. - Highlights: • Irradiated CAFs accelerated invasiveness and scattering of ESCC cell lines. • Irradiated CAFs promoted EMT of ESCC cells. • Irradiated fibroblasts induced nuclear β-catenin relocalization in ESCC cells. • Irradiated fibroblasts increased HDGF expression in vitro and in vivo.« less

Reproductive responses to photoperiod persist in olfactory bulbectomized Siberian hamsters (Phodopus sungorus).

PubMed

Prendergast, Brian J; Pyter, Leah M; Galang, Jerome; Kay, Leslie M

2009-03-02

In reproductively photoperiodic Syrian hamsters, removal of the olfactory bulbs (OBx) leads to a marked and sustained increase in gonadotrophin secretion which prevents normal testicular regression in short photoperiods. In contrast, among reproductively nonphotoperiodic laboratory strains of rats and mice, bulbectomy unmasks reproductive responses to photoperiod. The role of the olfactory bulbs has been proposed to have opposite effects on responsiveness to photoperiod, depending on the photoperiodicity of the reproductive system; however, Syrian hamsters are the only reproductively photoperiodic rodent species for which the role of the olfactory bulb in reproductive endocrinology has been assessed. This experiment evaluated the role of the olfactory bulbs in the photoperiodic control of reproduction in Siberian hamsters (Phodopus sungorus), an established model species for the study of neural substrates mediating seasonality. Relative to control hamsters housed in long days (15 h light/day), exposure of adult male hamsters to short days (9h light/day) for 8 weeks led to a temporal expansion of the pattern of nocturnal locomotor activity, testicular regression, decreases in testosterone (T) production, and undetectable levels of plasma follicle-stimulating hormone (FSH). Bilateral olfactory bulbectomy failed to affect any of these responses to short days. The patterns of entrainment to long and short days suggests that pre-pineal mechanisms involved in photoperiodic timekeeping are functioning normally in OBx hamsters. The absence of increases in FSH following bulbectomy in long days is incompatible with the hypothesis that the olfactory bulbs provide tonic inhibition of the HPG axis in this species. In marked contrast to Syrian hamsters, the olfactory bulbs of Siberian hamsters play essentially no role in the modulation of tonic gonadotrophin production or gonadotrophin responses to photoperiod.

Thermostability of sperm nuclei assessed by microinjection into hamster oocytes

EPA Science Inventory

Nuclei isolated from spermatozoa of various species (golden hamster, mouse, human, rooster, and the fish tilapia) were heated at 60 degrees-125 degrees C for 20-120 min and then microinjected into hamster oocytes to determine whether they could decondense and develop into pronucl...

Cancer Cell Radiobiological Studies Using In-House-Developed α-Particle Irradiator.

PubMed

Nilsson, Jenny; Bauden, Monika Posaric; Nilsson, Jonas M; Strand, Sven-Erik; Elgqvist, Jörgen

2015-11-01

An α-particle irradiator, enabling high-precision irradiation of cells for in vitro studies, has been constructed. The irradiation source was a (241)Am source, on which well inserts containing cancer cells growing in monolayer were placed. The total radioactivity, uniformity, and α-particle spectrum were determined by use of HPGe detector, Gafchromic dosimetry film, and PIPS detector measurements, respectively. Monte Carlo simulations were used for dosimetry. Three prostate cancer (LNCaP, DU145, PC3) and three pancreatic cancer (Capan-1, Panc-1, BxPC-3) cell lines were irradiated by α-particles to the absorbed doses 0, 0.5, 1, and 2 Gy. For reference, cells were irradiated using (137)Cs to the absorbed doses 0, 1, 2, 4, 6, 8, and 10 Gy. Radiation sensitivity was estimated using a tetrazolium salt-based colorimetric assay with absorbance measurements at 450 nm. The relative biological effectiveness for α-particles relative to γ-irradiation at 37% cell survival for the LNCaP, DU145, PC3, Capan-1, Panc-1, and BxPC-3 cells was 7.9 ± 1.7, 8.0 ± 0.8, 7.0 ± 1.1, 12.5 ± 1.6, 9.4 ± 0.9, and 6.2 ± 0.7, respectively. The results show the feasibility of constructing a desktop α-particle irradiator as well as indicate that both prostate and pancreatic cancers are good candidates for further studies of α-particle radioimmunotherapy.

Black tea extract and dental caries formation in hamsters.

PubMed

Linke, Harald A B; LeGeros, Racquel Z

2003-01-01

Several studies have suggested that green tea and Oolong tea extracts have antibacterial and anticariogenic properties in vitro and in vivo. The aim of the present study was to determine the effect of a standardized black tea extract (BTE) on caries formation in inbred hamsters on a regular and a cariogenic diet. Eighty hamsters were divided into four groups of 20 animals each. Two groups received a pelleted regular diet (LabChow) with water or BTE ad libitum. The other two groups received a powdered cariogenic diet (Diet 2000, containing 56% sucrose) with water or BTE ad libitum. The animals were kept for 3 months on their respective diets and then were sacrificed. The heads were retained, the jaws were prepared and stained using alizarin mordant red II, and were then scored for dental caries according to the Keyes method. This is the first study indicating that BTE, as compared with water, significantly decreased caries formation by 56.6% in hamsters on a regular diet and by 63.7% in hamsters on a cariogenic diet (P < 0.05). In the cariogenic diet group BTE, reduced the mandibular caries score of the hamsters slightly more than the maxillary caries score. The fluoride content of the standardized BTE solution was frequently monitored during the experiment; the mean fluoride concentration was found to be 4.22 ppm. A frequent intake of black tea can significantly decrease caries formation, even in the presence of sugars in the diet.

Time-Lapse Cinemicrographic Studies of X-Irradiated HeLa S3 Cells

PubMed Central

Hurwitz, Camilla; Tolmach, L. J.

1969-01-01

Analysis of time-lapse cinemicrographs of X-irradiated HeLa S3 cells has shown that the incidence of cell fusion was increased from 0.9% (following 1267 divisions) in control cells to an average of 22% (following 655 divisions) in cells irradiated with 500 rad doses of 220 kv X-rays. The incidence depended on the stage of the generation cycle at which the parent cells were irradiated. It was nearly constant in the first three postirradiation generations. Fusion occurred at all stages of the generation cycle, but preferentially during the first 20%. Cells undergoing fusion progressed more slowly through the generation cycle and had a higher probability of disintegrating than did irradiated cells that did not fuse. The occurrence of fusion was clonally distributed in the population. It took place only between sister (or closely related) cells. Protoplasmic bridges were often visible between sister cells prior to fusion. Giant cells arose only as a result of fusion. The incidence of multipolar divisions, though higher than in unirradiated cells, was only 5.5% in cultures irradiated with 500 rads. Fusion occurred following 85% of the multipolar divisions and was often followed by a multipolar division. ImagesFigure 1 PMID:5807221

The hamster flank organ model: Is it relevant to man

DOE Office of Scientific and Technical Information (OSTI.GOV)

Franz, T.J.; Lehman, P.A.; Pochi, P.

1989-10-01

The critical role that androgens play in the etiology of acne has led to a search for topically active antiandrogens and the frequent use of the flank organ of the golden Syrian hamster as an animal model. 17-alpha-propyltestosterone (17-PT) has been identified as having potent antiandrogenic activity in the hamster model, and this report describes its clinical evaluation. Two double-blind placebo controlled studies comparing 4% 17-PT in 80% alcohol versus vehicle alone were conducted. One study examined 17-PT sebosuppressive activity in 20 subjects. The second study examined its efficacy in 44 subjects having mild to moderate acne. A third studymore » measured in vitro percutaneous absorption of 17-PT through hamster flank and monkey skin, and human face skin in-vivo, using radioactive drug. 17-PT was found to be ineffective in reducing either the sebum excretion rate or the number of inflammatory acne lesions. Failure of 17-PT to show clinical activity was not a result of poor percutaneous absorption. Total absorption in man was 7.7% of the dose and only 1.0% in the hamster. The sebaceous gland of hamster flank organ is apparently more sensitive to antiandrogens than the human sebaceous gland.« less

Aryl- and alkyl-phosphorus-containing flame retardants induced mitochondrial impairment and cell death in Chinese hamster ovary (CHO-k1) cells.

PubMed

Huang, Chao; Li, Na; Yuan, Shengwu; Ji, Xiaoya; Ma, Mei; Rao, Kaifeng; Wang, Zijian

2017-11-01

Phosphorus-containing flame retardants (PFRs) are increasingly in demand worldwide as replacements for brominated flame retardants (BFRs), but insufficient available toxicological information on PFRs makes assessing their health risks challenging. Mitochondria are important targets of various environmental pollutants, and mitochondrial dysfunction may lead to many common diseases. In the present study, mitochondria impairment-related endpoints were measured by a high content screening (HCS) assay for 11 selected non-halogen PFRs in Chinese hamster ovary (CHO-k1) cells. A cluster analysis was used to categorize these PFRs into three groups according to their structural characteristics and results from the HCS assay. Two groups, containing long-chain alkyl-PFRs and all aryl-PFRs, were found to cause mitochondrial impairment but showed different mechanisms of toxicity. Due to the high correlation between cell death and mitochondrial impairment, two PFRs with different structures, trihexyl phosphate (THP) and cresyl diphenyl phosphate (CDP), were selected and compared with chlorpyrifos (CPF) to elucidate their mechanism of inducing cell death. THP (an alkyl-PFR) was found to utilize a similar pathway as CPF to induce apoptosis. However, cell death induced by CDP (an aryl-PFR) was different from classical necrosis based on experiments to discriminate among the different modes of cell death. These results confirm that mitochondria might be important targets for some PFRs and that differently structured PFRs could function via distinct mechanisms of toxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Identification, Expression, and Physiological Functions of Siberian Hamster Gonadotropin-Inhibitory Hormone

PubMed Central

Ubuka, Takayoshi; Inoue, Kazuhiko; Fukuda, Yujiro; Mizuno, Takanobu; Ukena, Kazuyoshi; Kriegsfeld, Lance J.

2012-01-01

Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic neuropeptide that inhibits gonadotropin secretion in birds and mammals. To further understand its physiological roles in mammalian reproduction, we identified its precursor cDNA and endogenous mature peptides in the Siberian hamster brain. The Siberian hamster GnIH precursor cDNA encoded two RFamide-related peptide (RFRP) sequences. SPAPANKVPHSAANLPLRF-NH2 (Siberian hamster RFRP-1) and TLSRVPSLPQRF-NH2 (Siberian hamster RFRP-3) were confirmed as mature endogenous peptides by mass spectrometry from brain samples purified by immunoaffinity chromatography. GnIH mRNA expression was higher in long days (LD) compared with short days (SD). GnIH mRNA was also highly expressed in SD plus pinealectomized animals, whereas expression was suppressed by melatonin, a nocturnal pineal hormone, administration. GnIH-immunoreactive (-ir) neurons were localized to the dorsomedial region of the hypothalamus, and GnIH-ir fibers projected to hypothalamic and limbic structures. The density of GnIH-ir perikarya and fibers were higher in LD and SD plus pinealectomized hamsters than in LD plus melatonin or SD animals. The percentage of GnRH neurons receiving close appositions from GnIH-ir fiber terminals was also higher in LD than SD, and GnIH receptor was expressed in GnRH-ir neurons. Finally, central administration of hamster RFRP-1 or RFRP-3 inhibited LH release 5 and 30 min after administration in LD. In sharp contrast, both peptides stimulated LH release 30 min after administration in SD. These results suggest that GnIH peptides fine tune LH levels via its receptor expressed in GnRH-ir neurons in an opposing fashion across the seasons in Siberian hamsters. PMID:22045661

Effect of curcumin on pathogenesis of hamster-opisthorchiasis through apoptosis-related gene expression.

PubMed

Sriraj, Pranee; Boonmars, Thidarut; Boonjaraspinyo, Sirintip; Kaewsamut, Butsara; Srisawangwong, Tuanchai; Sithithaworn, Paiboon; Wu, Zhiliang

2009-11-01

The present study investigated the effect of curcumin, a phenolic compound with yellow color from Curcuma longa L., on the expression of the apoptosis-related genes [BAX (Bcl-2 associated protein X), PKB, p53, MDM2 (mouse double minute 2), caspase 9, c-Ski, smad1 and smad4] in hamster opisthorchiasis. On Opisthorchis viverrini infection treated with dietary curcumin apoptosis-related gene expression profiles were similar to O. viverrini-infected group, but the expression levels seemed lower. Light microscopic observation revealed that aggregation of inflammatory cells surrounding the hepatic bile ducts in the groups infected with O. viverrini and treated with dietary curcumin was lower than in infected group. The intensity of the response is correlated with expression of the genes studied. The results suggest that curcumin reduces pathogenesis in hamster-opisthorchiasis by controlling apoptosis-related gene expression.

Dose-rate effect was observed in T98G glioma cells following BNCT.

PubMed

Kinashi, Yuko; Okumura, Kakuji; Kubota, Yoshihisa; Kitajima, Erika; Okayasu, Ryuichi; Ono, Koji; Takahashi, Sentaro

2014-06-01

It is generally said that low LET radiation produce high dose-rate effect, on the other hand, no significant dose rate effect is observed in high LET radiation. Although high LET radiations are produced in BNCT, little is known about dose-rate effect of BNCT. T98G cells, which were tumor cells, were irradiated by neutron mixed beam with BPA. As normal tissue derived cells, Chinese hamster ovary (CHO-K1) cells and DNA double strand breaks (DNA-DSBs) repair deficient cells, xrs5 cells were irradiated by the neutrons (not including BPA). To DNA-DSBs analysis, T98G cells were stained immunochemically with 53BP1 antibody. The number of DNA-DSBs was determined by counting 53BP1 foci. There was no dose-rate effect in xrs5 cells. D0 difference between 4cGy/min and 20cGy/min irradiation were 0.5 and 5.9 at the neutron and gamma-ray irradiation for CHO-K1, and 0.3 at the neutron for T98G cells. D0 difference between 20cGy/min and 80cGy/min irradiation for T98G cells were 1.2 and 0.6 at neutron irradiation plus BPA and gamma-ray. The differences between neutron irradiations at the dose rate in T98G cells were supported by not only the cell viability but also 53BP1 foci assay at 24h following irradiation to monitor DNA-DSBs. Dose-rate effect of BNCT when T98G cells include 20ppm BPA was greater than that of gamma-ray irradiation. Moreover, Dose-rate effect of the neutron beam when CHO-K1 cells did not include BPA was less than that of gamma-ray irradiation These present results may suggest the importance of dose-rate effect for more efficient BNCT and the side effect reduction. © 2013 Published by Elsevier Ltd.

Stable expression of recombinant human coagulation factor XIII in protein-free suspension culture of Chinese hamster ovary cells.

PubMed

Chun, B H; Bang, W G; Park, Y K; Woo, S K

2001-11-01

The recombinant a and bsubunits for human coagulation factor XIII were transfected into Chinese hamster ovary (CHO) cells. CHO cells were amplified and selected with methotrexate in adherent cultures containing serum, and CHO 1-62 cells were later selected in protein-free medium. To develop a recombinant factor XIII production process in a suspension culture, we have investigated the growth characteristics of CHO cells and the maintenance of factor XIII expression in the culture medium. Suspension adaptation of CHO cells was performed in protein-free medium, GC-CHO-PI, by two methods, such as serum weaning and direct switching from serum containing media to protein-free media. Although the growth of CHO cells in suspension culture was affected initially by serum depletion, cell specific productivity of factor XIII showed only minor changes by the direct switching to protein-free medium during a suspension culture. As for the long-term stability of factor XIII, CHO 1-62 cells showed a stable expression of factor XIII in protein-free condition for 1000 h. These results indicate that the CHO 1-62cells can be adapted to express recombinant human factor XIII in a stable maimer in suspension culture using a protein-free medium. Our results demonstrate that enhanced cell growth in a continuous manner is achievable for factor XIII production in a protein-free medium when a perfusion bioreactor culture system with a spin filter is employed.

Phosphorylation of 3-deazaguanosine by nicotinamide riboside kinase in Chinese hamster ovary cells.

PubMed

Saunders, P P; Tan, M T; Spindler, C D; Robins, R K

1989-12-01

The growth inhibitory activity of 3-deazaguanosine toward a mutant line (TGR-3) of Chinese hamster ovary cells deficient in hypoxanthine-guanine phosphoribosyltransferase (EC 2.4.2.8) was substantially reversed by the simultaneous addition of nicotinamide riboside. The activities of most other ribonucleoside analogues tested were unaffected. The formation of cellular 3-deazaGMP and 3-deazaGTP from the ribonucleoside analogue, as measured by high-pressure liquid chromatography, was inhibited by the presence of nicotinamide riboside. The inhibition was dependent on concentration of 3-deazaguanosine and could also be demonstrated by following the metabolism of 3-deazaguanosine, labeled with 14C in the ribose moiety, to [14C]3-deazaGTP. In the presence of 100 microM nicotinamide riboside formation of the labeled triphosphate derivative of 3-deazaguanosine was undetectable. A 3-deazaguanosine phosphorylating activity was separated from other cellular kinases by DEAE-cellulose chromatography. Contaminating purine nucleoside phosphorylase (EC 2.4.2.1) was subsequently removed by sucrose density gradient centrifugation. The resulting enzyme preparation demonstrated the greatest activities with nicotinamide riboside and 3-deazaguanosine and, in addition, could also phosphorylate tiazofurin and guanosine to lesser, but significant, degrees. These and other observations suggest that 3-deazaguanosine, and perhaps other agents such as tiazofurin, may, at least in part, be phosphorylated by a nicotinamide ribonucleoside kinase in these cells. If so, it is possible that the activity of this agent in other types of cells in vivo could be dependent upon the presence of this enzyme and that it could be influenced by cellular concentrations of the natural pyridine nucleoside.

The Syrian hamster embryo cells transformation assay identifies efficiently nongenotoxic carcinogens, and can contribute to alternative, integrated testing strategies.

PubMed

Benigni, Romualdo; Bossa, Cecilia; Tcheremenskaia, Olga; Battistelli, Chiara Laura; Giuliani, Alessandro

2015-02-01

The long-term carcinogenesis bioassays have played a central role in protecting human health, but for ethical and practical reasons their use is dramatically diminishing and the genotoxicity short-term tests have taken the pivotal role in the pre-screening of chemical carcinogenicity. However, this strategy cannot detect nongenotoxic carcinogens. Since up to 25% of IARC human carcinogens are recognized to have nongenotoxic mechanisms of action, the risk they pose to human health cannot be disregarded, and it is urgent to fill the gap in the tools for alternative testing. In this paper, we analyze from different perspectives the ability of Cell Transformation Assays to identify nongenotoxic carcinogens, and we conclude that the Syrian hamster embryo cells test is able to identify nongenotoxic carcinogens with 80-90% efficiency, and thus, can play an important role in integrated, alternative testing strategies. Copyright © 2015 Elsevier B.V. All rights reserved.

RESISTANCE TO X-IRRADIATION BY EMBRYONIC CELLS OF THE LIMB-BUDS OF TADPOLES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, B.M.; Ewell, L.M.

1959-01-01

Both total-body irradiation and shielding of the trunk were used to study the effects of x irradiation from 1000 to 30000 r upon the limb-buds of Bufo boreas and Hyla regilla tadpoles. The object was to test the view that the younger the cells the more sensitive they are to irradiation. The answer is negative. If there is any special susceptibility of these undifferentiated cells it should appear at levels far below the 30000 r maximum employed. A sharp distinction is made between the very susceptible mitotic cells and the resistant non-dividing embryonic cells that have been accumulated in suchmore » numbers that they may rapidly differentiate into the characteristic limb tissues under the stimulus of the thyroid hormone. Many irradiated ectoderm cells were changed to form bizarre excrescences but were not destroyed. Unicellular cuthneous gland cells continued to arise even after the heaviest irradiation. Irradiated tadpoles with hind limb-buds from 0.6 mm down to 0.2 mm length were unable to develop normal limbs. This capacity was propontional to the number of non-dividing embryonic cells stored at the time of irradiation. Irradiation of 5000, equal degree but the rapidity was greatest in the cases of higher dosage. Not only did these levels of irradiation fail to destroy the non-dividing embryonic cells but they did not effect their pre-deterrmined specificity nor modify their capacity for subsequent differentiation and growth. Exposure to a thyroxin solution caused the hind limb-buds without visible differentiation of cells to grow from a length of 0.8 or 0.9 mm or 1.0 mm at the time of irradiation to a length of as much as 5.0 mm in the course of 7 days. Development of thigh, shank, ankle, and toes was complete. Microscopic studies showed characteristic tissues such as cartilage, connective tissue, and muscle, developed to a comparable degree in control and irradiated specimens. (auth)« less

Cloning and characterization of the hamster and guinea pig nicotinic acid receptors.

PubMed

Torhan, April Smith; Cheewatrakoolpong, Boonlert; Kwee, Lia; Greenfeder, Scott

2007-09-01

In this study, we present the identification and characterization of hamster and guinea pig nicotinic acid receptors. The hamster receptor shares approximately 80-90% identity with the nucleotide and amino acid sequences of human, mouse, and rat receptors. The guinea pig receptor shares 76-80% identity with the nucleotide and amino acid sequences of these other species. [(3)H]nicotinic acid binding affinity at guinea pig and hamster receptors is similar to that in human (dissociation constant = 121 nM for guinea pig, 72 nM for hamster, and 74 nM for human), as are potencies of nicotinic acid analogs in competition binding studies. Inhibition of forskolin-stimulated cAMP production by nicotinic acid and related analogs is also similar to the activity in the human receptor. Analysis of mRNA tissue distribution for the hamster and guinea pig nicotinic acid receptors shows expression across a number of tissues, with higher expression in adipose, lung, skeletal muscle, spleen, testis, and ovary.

Electrophysiological characteristics of hamster dorsal root ganglion cells and their response to axotomy.

PubMed

Gurtu, S; Smith, P A

1988-02-01

1. The active and passive membrane properties of neurons in the lower lumbar (L6, L7) or sacral (S1) dorsal root ganglia from golden hamsters were examined in vitro by means of conventional intracellular recording techniques. Data were collected from neurons exhibiting action potentials (AP) of 70 mV or more in amplitude. 2. Cells with axonal conduction velocities (CV) greater than 20 m/s were termed fast-A-cells, those with CVs between 2.5 and 20 m/s were termed A-delta-cells, and those with CVs less than 1 m/s were termed C-cells. 3. Fast-A-cells usually exhibited short-duration APs (2.51 +/- 0.41 ms, n = 19) followed by short (less than 50 ms) afterhyperpolarizations (AHPs). C-cells usually exhibited long-duration APs (10.5 +/- 0.69 ms, n = 18) followed by long-duration AHPs (much greater than 50 ms). The characteristics of APs in A-delta-cells (AP mean duration 3.34 +/- 0.42 ms, n = 32) were intermediate between those of fast-A- and C-cells. Long AHPs (duration much greater than 50 ms) were manifest in 43.8% of A-delta-cells. 4. A time-dependent sag in hyperpolarizing electrotonic potentials (rectification) was found in 68.8% of fast-A-cells, 45.5% of A-delta-cells, and 62.5% of C-cells. 5. To examine neuronal properties 1-6 wk after transection of the sciatic nerve (axotomy), cells were reclassified as SAP (short action potential) cells and LAP (long action potential) cells. Cells in the SAP category had AP durations less than 5 ms and included all fast-A-cells and the majority of A-delta-cells. The LAP category included cells with AP durations greater than 8 ms contained only C-cells. 6. Axotomy failed to decrease the CV of LAP cells or A-delta-cells in the SAP group. The CV of LAP cells may have increased (P less than 0.05), whereas that of SAP cells was unchanged. 7. The duration of the AP and AHP of SAP cells were slightly increased (0.1 greater than P greater than 0.05), whereas AP and AHP duration of LAP cells were unchanged after axotomy. AHP amplitudes

Hibernation, stress, intestinal functions, and catecholoamine turnover rate in hamsters and gerbils

NASA Technical Reports Server (NTRS)

Musacchia, X. J.

1973-01-01

Bioenergetic studies on hamsters during depressed metabolic states are reported. External support of blood glucose extended the survival times of hibernating animals. Radioresistance increased in hibernating as well as in hypothermic hamsters. Marked changes in hamster catecholamine turnover rates were observed during acclimatization to high temperature stress. High radioresistance levels of the gerbil gastrointestinal system were attributed in part to the ability of the gut to maintain functional integrity.

Photoperiod history differentially impacts reproduction and immune function in adult Siberian hamsters.

PubMed

Prendergast, Brian J; Pyter, Leah M

2009-12-01

Seasonal changes in numerous aspects of mammalian immune function arise as a result of the annual variation in environmental day length (photoperiod), but it is not known if absolute photoperiod or relative change in photoperiod drives these changes. This experiment tested the hypothesis that an individual's history of exposure to day length determines immune responses to ambiguous, intermediate-duration day lengths. Immunological (blood leukocytes, delayed-type hypersensitivity reactions [DTH]), reproductive, and adrenocortical responses were assessed in adult Siberian hamsters (Phodopus sungorus) that had been raised initially in categorically long (15-h light/day; 15L) or short (9L) photoperiods and were subsequently transferred to 1 of 7 cardinal experimental photoperiods between 9L and 15L, inclusive. Initial photoperiod history interacted with contemporary experimental photoperiods to determine reproductive responses: 11L, 12L, and 13L caused gonadal regression in hamsters previously exposed to 15L, but elicited growth in hamsters previously in 9L. In hamsters with a 15L photoperiod history, photoperiods < or = 11L elicited sustained enhancement of DTH responses, whereas in hamsters with a 9L photoperiod history, DTH responses were largely unaffected by increases in day length. Enhancement and suppression of blood leukocyte concentrations occurred at 13L in hamsters with photoperiod histories of 15L and 9L, respectively; however, prior exposure to 9L imparted marked hysteresis effects, which suppressed baseline leukocyte concentrations. Cortisol concentrations were only enhanced in 15L hamsters transferred to 9L and, in common with DTH, were unaffected by photoperiod treatments in hamsters with a 9L photoperiod history. Photoperiod history acquired in adulthood impacts immune responses to photoperiod, but manifests in a markedly dissimilar fashion as compared to the reproductive system. Prior photoperiod exposure has an enduring impact on the ability of the

Acute brown adipose tissue temperature response to cold in monosodium glutamate-treated Siberian hamsters

PubMed Central

Leitner, Claudia; Bartness, Timothy J.

2014-01-01

Neonatal monosodium glutamate (MSG) administration increases adiposity, decreases energy expenditure and is associated with arcuate nucleus (Arc) destruction. Disrupted brown adipose tissue (BAT) thermogenesis underlies some of these effects, although, interscapular BAT temperature (TIBAT) has not been measured. Therefore, we tested the effects of neonatal MSG or vehicle administration in Siberian hamsters and, when they were adults, measured TIBAT during acute cold exposure. The Arc and its projection to the hypothalamic paraventricular nucleus (PVH) are both components of the CNS outflow circuits to IBAT, with the latter implicated in BAT thermogenesis that could be compromised by MSG treatment. Using a viral transneuronal tract tracer, pseudorabies virus (PRV), we also tested whether the components of these circuits were intact. As adults, MSG-treated hamsters had significantly increased body mass and some white fat pad masses, markedly reduced Arc Nissl and neuropeptide staining, and PVH neuropeptide fiber staining. Cold-exposed (18 h at 5 °C) MSG- and vehicle-treated hamsters initially maintained TIBAT, but the ability of the former waned after 2 h being significantly decreased by 18 h. PRV immunoreactive fibers/cells were not altered by neonatal MSG treatment despite substantial Arc and PVH destruction. MSG- and vehicle-treated hamsters given an exogenous norepinephrine challenge showed identical increases in the duration and peak of TIBAT. Thus, the inability of MSG-treated animals to sustain TIBAT in the cold is not due to any obvious MSG-induced deletions of central sympathetic outflow circuits to IBAT, but appears to be extrinsic to the tissue nevertheless. PMID:19643091

Infestivity of Demodex canis to hamster skin engrafted onto SCID mice.

PubMed

Tani, Kenji; Une, Satoshi; Hasegawa, Atsuhiko; Adachi, Makoto; Kanda, Naoko; Watanabe, Shin-ichi; Nakaichi, Munekazu; Taura, Yasuho

2005-04-01

We demonstrated that Demodex canis was transferred to skin xenografts of a dog and a hamster onto severe combined immunodeficiency mice. After the transfer of mites, the number of eggs, larvae, nymphs and adult mites per gram of canine and hamster xenografts increased, whereas no live mites were detected on murine allograft. These results indicate that D. canis proliferates in hair follicles of dog and hamster skins but not in murine allograft. Therefore, D. canis may have host preference but not strict host-specificity.

Carbon Ion Irradiation Inhibits Glioma Cell Migration Through Downregulation of Integrin Expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rieken, Stefan, E-mail: Stefan.Rieken@med.uni-heidelberg.de; Habermehl, Daniel; Wuerth, Lena

2012-05-01

Purpose: To investigate the effect of carbon ion irradiation on glioma cell migration. Methods and Materials: U87 and Ln229 glioma cells were irradiated with photons and carbon ions. Migration was analyzed 24 h after irradiation. Fluorescence-activated cell sorting analysis was performed in order to quantify surface expression of integrins. Results: Single photon doses of 2 Gy and 10 Gy enhanced {alpha}{sub {nu}}{beta}{sub 3} and {alpha}{sub {nu}}{beta}{sub 5} integrin expression and caused tumor cell hypermigration on both vitronectin (Vn) and fibronectin (Fn). Compared to integrin expression in unirradiated cells, carbon ion irradiation caused decreased integrin expression and inhibited cell migration onmore » both Vn and Fn. Conclusion: Photon radiotherapy (RT) enhances the risk of tumor cell migration and subsequently promotes locoregional spread via photon induction of integrin expression. In contrast to photon RT, carbon ion RT causes decreased integrin expression and suppresses glioma cell migration on both Vn and Fn, thus promising improved local control.« less

Neurons identified by NeuN/Fox-3 immunoreactivity have a novel distribution in the hamster and mouse suprachiasmatic nucleus.

PubMed

Morin, Lawrence P; Hefton, Sara; Studholme, Keith M

2011-11-03

The suprachiasmatic nucleus (SCN) has several structural characteristics and cell phenotypes shared across species. Here, we describe a novel feature of SCN anatomy that is seen in both hamster and mouse. Frozen sections through the SCN were obtained from fixed brains and stained for the presence of immunoreactivity to neuronal nuclear protein (NeuN-IR) using a mouse monoclonal antibody which is known to exclusively identify neurons. NeuN-IR did not identify all SCN neurons as medial NeuN-IR neurons were generally not present. In the hamster, NeuN-IR cells are present rostrally, scattered in the dorsal half of the nucleus. More caudally, the NeuN-IR cells are largely, but not exclusively, scattered inside the lateral and dorsolateral border. At mid- to mid-caudal SCN levels, a dense group of NeuN-IR cells extends from the dorsolateral border ventromedially to encompass the central subnucleus of the SCN (SCNce). The pattern is similar in the mouse SCN. NeuN-IR does not co-localize with either cholecystokinin- or vasoactive intestinal polypeptide, but does with vasopressin-IR in the caudal SCN. In the hamster SCNce, numerous cells contain both calbindin- and NeuN-IR. The distribution of NeuN-IR cells in the SCN is unique, especially with regard to its generally lateral location through the length of the nucleus. The distribution of NeuN-IR cells is not consistent with most schemas representing SCN organization or with terminology referring to its widely accepted subdivisions. NeuN has recently been identified as Fox-3 protein. Its function in the SCN is not known, nor is it known why a large proportion of SCN cells do not contain NeuN-IR. Copyright © 2011 Elsevier B.V. All rights reserved.

Cross-species transcriptomic approach reveals genes in hamster implantation sites.

PubMed

Lei, Wei; Herington, Jennifer; Galindo, Cristi L; Ding, Tianbing; Brown, Naoko; Reese, Jeff; Paria, Bibhash C

2014-12-01

The mouse model has greatly contributed to understanding molecular mechanisms involved in the regulation of progesterone (P4) plus estrogen (E)-dependent blastocyst implantation process. However, little is known about contributory molecular mechanisms of the P4-only-dependent blastocyst implantation process that occurs in species such as hamsters, guineapigs, rabbits, pigs, rhesus monkeys, and perhaps humans. We used the hamster as a model of P4-only-dependent blastocyst implantation and carried out cross-species microarray (CSM) analyses to reveal differentially expressed genes at the blastocyst implantation site (BIS), in order to advance the understanding of molecular mechanisms of implantation. Upregulation of 112 genes and downregulation of 77 genes at the BIS were identified using a mouse microarray platform, while use of the human microarray revealed 62 up- and 38 down-regulated genes at the BIS. Excitingly, a sizable number of genes (30 up- and 11 down-regulated genes) were identified as a shared pool by both CSMs. Real-time RT-PCR and in situ hybridization validated the expression patterns of several up- and down-regulated genes identified by both CSMs at the hamster and mouse BIS to demonstrate the merit of CSM findings across species, in addition to revealing genes specific to hamsters. Functional annotation analysis found that genes involved in the spliceosome, proteasome, and ubiquination pathways are enriched at the hamster BIS, while genes associated with tight junction, SAPK/JNK signaling, and PPARα/RXRα signalings are repressed at the BIS. Overall, this study provides a pool of genes and evidence of their participation in up- and down-regulated cellular functions/pathways at the hamster BIS. © 2014 Society for Reproduction and Fertility.

Analysis of Giant-nucleated Cell Formation Following X-ray and Proton Irradiations

NASA Astrophysics Data System (ADS)

Almahwasi, Ashraf Abdu

Radiation-induced genetic instability has been observed in survivors of irradiated cancerous and normal cells in vitro and in vivo and has been determined in different forms, such as delayed cell death, chromosomal aberration or mutation. A well defined and characterized normal human-diploid AG1522 fibroblast cell line was used to study giant-nucleated cell (GCs) formation as the ultimate endpoint of this research. The average nuclear cross-sectional areas of the AG1522 cells were measured in mum2. The doubling time required by the AG1522 cells to divide was measured. The potential toxicity of the Hoechst dye at a working concentration on the live AG1522 cells was assessed. The yield of giant cells was determined at 7, 14 and 21 days after exposure to equivalent clinical doses of 0.2, 1 or 2 Gy of X-ray or proton irradiation. Significant differences were found to exist between X-ray or proton irradiation when compared with sham-irradiated control populations. The frequency of GCs induced by X-rays was also compared to those formed in proton irradiated cultures. The results confirm that 1 Gy X-rays are shown to induce higher rates of mitotically arrested GCs, increasing continually over time up to 21 days post-irradiation. The yield of GCs was significantly greater (10%) compared to those formed in proton populations (2%) 21 days postirradiation. The GCs can undergo a prolonged mitotic arrest that significantly increases the length of cell cycle. The arrest of GCs at the mitotic phase for longer periods of time might be indicative of a strategy for cell survival, as it increases the time available for DNA repair and enables an alternative route to division for the cells. However, the reduction in their formation 21 days after both types of radiation might favour GCs formation, ultimately contributing to carcinogenesis or cancer therapy resistance. The X-ray experiments revealed a dose-dependent increase in the GCs up to 14 days after irradiation. Although the proton

Pentoxifylline increases sperm penetration into zona-free hamster oocytes without increasing the acrosome reaction.

PubMed

Morales, P; Llanos, M; Yovich, J L; Cummins, J M; Vigil, P

1993-01-01

Several drugs have been used to stimulate human sperm motility, including 3-deoxy-adenosine, caffeine, and pentoxifylline. Pentoxifylline is an inhibitor of the phosphodiesterase and may stimulate sperm motility by increasing the intracellular levels of cAMP. In this study we have evaluated the effect of pentoxifylline in the outcome of the sperm penetration assay into zona-free hamster oocytes. Twenty-seven semen samples, obtained for diagnostic purposes, were used. After the motile sperm were selected by the swim-up technique, the samples were divided into two aliquots. One aliquot was incubated with 1 mg ml-1 of pentoxifylline at 37 degrees C, 5% CO2 for 30 min. The control aliquot was incubated with culture medium. The samples were then washed and resuspended in fresh, pentoxifylline-free medium, at a sperm concentration of 10 x 10(6) cells ml-1. One hundred microlitres of each sperm suspension was then deposited under oil and 30-40 zona-free hamster oocytes were added. After 6 h of gamete coincubation, the percentage of penetrated oocytes and the number of decondensed sperm heads were evaluated. The percentage of acrosome-reacted sperm was evaluated using the Pisum sativum lectin. The percentage of zona-free hamster oocytes penetrated was increased after pentoxifylline-treatment. The percentage of acrosome reacted sperm and the number of decondensed sperm heads per egg were not different between the control and the pentoxifylline-treated groups. The results suggest that the beneficial effect of pentoxifylline upon the sperm cells is not mediated by stimulation of the acrosome reaction.

Cell cycle tracking for irradiated and unirradiated bystander cells in a single colony with exposure to a soft X-ray microbeam.

PubMed

Kaminaga, Kiichi; Noguchi, Miho; Narita, Ayumi; Hattori, Yuya; Usami, Noriko; Yokoya, Akinari

2016-11-01

To establish a new experimental technique to explore the photoelectric and subsequent Auger effects on the cell cycles of soft X-ray microbeam-irradiated cells and unirradiated bystander cells in a single colony. Several cells located in the center of a microcolony of HeLa-Fucci cells consisting of 20-80 cells were irradiated with soft X-ray (5.35 keV) microbeam using synchrotron radiation as a light source. All cells in the colony were tracked for 72 h by time-lapse microscopy imaging. Cell cycle progression, division, and death of each cell in the movies obtained were analyzed by pedigree assay. The number of cell divisions in the microcolony was also determined. The fates of these cells were clarified by tracking both irradiated and unirradiated bystander cells. Irradiated cells showed significant cell cycle retardation, explosive cell death, or cell fusion after a few divisions. These serious effects were also observed in 15 and 26% of the bystander cells for 10 and 20 Gy irradiation, respectively, and frequently appeared in at least two daughter or granddaughter cells from a single-parent cell. We successfully tracked the fates of microbeam-irradiated cells and unirradiated bystander cells with live cell recordings, which have revealed the dynamics of soft X-ray irradiated and unirradiated bystander cells for the first time. Notably, cell deaths or cell cycle arrests frequently arose in closely related cells. These details would not have been revealed by a conventional immunostaining imaging method. Our approach promises to reveal the dynamic cellular effects of soft X-ray microbeam irradiation and subsequent Auger processes from various endpoints in future studies.

Altered cytokeratin expression during chemoprevention of experimental hamster buccal pouch carcinogenesis by garlic.

PubMed

Balasenthil, S; Rao, K S; Nagini, S

2002-03-01

Cytokeratins (also known as keratins (K)) are members of the family of intermediate filaments and form major components of the mammalian epithelial cell cytoskeleton. Cytokeratins have emerged as reliable cellular markers of oral cancer development and chemoprevention because of their abundance, stability and high antigenicity. We investigated the effect of aqueous garlic extract on cytokeratin expression during 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. Hamsters were divided into four groups of six animals. Animals in group 1 were painted with a 0.5% solution of DMBA in liquid paraffin, on the right buccal pouches, three times a week for 14 weeks. Group 2 animals were painted with DMBA as in group 1 and also received 250 mg/kg body weight aqueous garlic extract orally on alternate days to the DMBA application. Group 3 animals received garlic extract only, as in group 2. Group 4 animals received neither DMBA nor garlic extract and served as the control. The hamsters were killed after an experimental period of 14 weeks. Cytokeratin expression was studied using human monoclonal antibodies AE1 and AE3, which react with type I and II keratins. In DMBA-induced squamous cell carcinomas, decreased expression of high molecular weight keratins was observed. Administration of garlic extract to animals painted with DMBA suppressed HBP carcinomas and restored normal cytokeratin expression. The results of the present study suggest that inhibition of HBP carcinogenesis by garlic may be due to its regulatory effects on differentiation, tumour invasiveness, migratory and metastatic potential. We suggest that one of the mechanisms of tumour inhibition by garlic is an influence on cellular differentiation.

Photoperiodic Regulation of the Orexigenic Effects of Ghrelin in Siberian Hamsters

PubMed Central

Bradley, Sean P.; Pattullo, Lucia M.; Patel, Priyesh N.; Prendergast, Brian J.

2010-01-01

Animals living in temperate climates with predictable seasonal changes in food availability may use seasonal information to engage different metabolic strategies. Siberian hamsters decrease costs of thermoregulation during winter by reducing food intake and body mass in response to decreasing or short day lengths (SD). These experiments examined whether SD reductions in food intake in hamsters is driven, at least in part, by altered behavioral responses to ghrelin, a gut-derived orexigenic peptide which induces food intake via NPY-dependent mechanisms. Relative to hamsters housed in long day (LD) photoperiods, SD hamsters consumed less food in response to i.p. treatment with ghrelin across a range of doses from 0.03 to 3 mg/kg. To determine whether changes in photoperiod alter behavioral responses ghrelin-induced activation of NPY neurons, c-Fos and NPY expression were quantified in the arcuate nucleus (ARC) via double-label fluorescent immunocytochemistry following i.p. treatment with 0.3 mg/kg ghrelin or saline. Ghrelin induced c-Fos immunoreactivity (-ir) in a greater proportion of NPY-ir neurons of LD relative to SD hamsters. In addition, following ghrelin treatment, a greater proportion of ARC c-Fos-ir neurons were identifiable as NPY-ir in LD relative to SD hamsters. Changes in day length markedly alter the behavioral response to ghrelin. The data also identify photoperiod-induced changes in the ability of ghrelin to activate ARC NPY neurons as a possible mechanism by which changes in day length alter food intake. PMID:20600050

Biological characterization of a novel in vitro cell irradiator

PubMed Central

Fowler, Tyler L.; Fisher, Michael M.; Bailey, Alison M.; Bednarz, Bryan P.

2017-01-01

To evaluate the overall robustness of a novel cellular irradiator we performed a series of well-characterized, dose-responsive assays to assess the consequences of DNA damage. We used a previously described novel irradiation system and a traditional 137Cs source to irradiate a cell line. The generation of reactive oxygen species was assessed using chloromethyl-H2DCFDA dye, the induction of DNA DSBs was observed using the comet assay, and the initiation of DNA break repair was assessed through γH2AX image cytometry. A high correlation between physical absorbed dose and biologic dose was seen for the production of intracellular reactive oxygen species, physical DNA double strand breaks, and modulation of the cellular double stand break pathway. The results compared favorably to irradiation with a traditional 137Cs source. The rapid, straightforward tests described form a reasonable approach for biologic characterization of novel irradiators. These additional testing metrics go beyond standard physics testing such as Monte Carlo simulation and thermo-luminescent dosimeter evaluation to confirm that a novel irradiator can produce the desired dose effects in vitro. Further, assessment of these biological metrics confirms that the physical handling of the cells during the irradiation process results in biologic effects that scale appropriately with dose. PMID:29232400

Phosphatidylserine biosynthesis in cultured Chinese hamster ovary cells. III. Genetic evidence for utilization of phosphatidylcholine and phosphatidylethanolamine as precursors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuge, O.; Nishijima, M.; Akamatsu, Y.

1986-05-05

We reported that Chinese hamster ovary (CHO) cells contain two different serine-exchange enzymes (I and II) which catalyze the base-exchange reaction of phospholipid(s) with serine and that a phosphatidylserine-requiring mutant (strain PSA-3) of CHO cells is defective in serine-exchange enzyme I and lacks the ability to synthesize phosphatidylserine. In this study, we examined precursor phospholipids for phosphatidylserine biosynthesis in CHO cells. When mutant PSA-3 and parent (CHO-K1) cells were cultured with (/sup 32/P)phosphatidylcholine, phosphatidylserine in the parent accumulated radioactivity while that in the mutant was not labeled significantly. On the contrary, when cultured with (/sup 32/P)phosphatidylethanolamine, the mutant incorporated themore » label into phosphatidylserine more efficiently than the parent. Furthermore, we found that mutant PSA-3 grew normally in growth medium supplemented with 30 microM phosphatidylethanolamine as well as phosphatidylserine and that the biosynthesis of phosphatidylserine in the mutant was normal when cells were cultured in the presence of exogenous phosphatidylethanolamine. The simplest interpretation of these findings is that phosphatidylserine in CHO cells is biosynthesized through the following sequential reactions: phosphatidylcholine----phosphatidylserine----phosphatidylethanolamine--- - phosphatidylserine. The three reactions are catalyzed by serine-exchange enzyme I, phosphatidylserine decarboxylase, and serine-exchange enzyme II, respectively.« less

Regulation of lipid metabolism by obeticholic acid in hyperlipidemic hamsters.

PubMed

Dong, Bin; Young, Mark; Liu, Xueqing; Singh, Amar Bahadur; Liu, Jingwen

2017-02-01

The farnesoid X receptor (FXR) plays critical roles in plasma cholesterol metabolism, in particular HDL-cholesterol (HDL-C) homeostasis. Obeticholic acid (OCA) is a FXR agonist being developed for treating various chronic liver diseases. Previous studies reported inconsistent effects of OCA on regulating plasma cholesterol levels in different animal models and in different patient populations. The mechanisms underlying its divergent effects have not yet been thoroughly investigated. The scavenger receptor class B type I (SR-BI) is a FXR-modulated gene and the major receptor for HDL-C. We investigated the effects of OCA on hepatic SR-BI expression and correlated such effects with plasma HDL-C levels and hepatic cholesterol efflux in hyperlipidemic hamsters. We demonstrated that OCA induced a time-dependent reduction in serum HDL-C levels after 14 days of treatment, which was accompanied by a significant reduction of liver cholesterol content and increases in fecal cholesterol in OCA-treated hamsters. Importantly, hepatic SR-BI mRNA and protein levels in hamsters were increased to 1.9- and 1.8-fold of control by OCA treatment. Further investigations in normolipidemic hamsters did not reveal OCA-induced changes in serum HDL-C levels or hepatic SR-BI expression. We conclude that OCA reduces plasma HDL-C levels and promotes transhepatic cholesterol efflux in hyperlipidemic hamsters via a mechanism involving upregulation of hepatic SR-BI.

Pulmonary toxicity in hamsters of smoke particles from Kuwaiti oil fires.

PubMed Central

Brain, J D; Long, N C; Wolfthal, S F; Dumyahn, T; Dockery, D W

1998-01-01

The Kuwaiti oil wells set on fire by retreating Iraqi troops at the end of the Persian Gulf War released complex particles, inorganic and organic gases, and hydrocarbons into the atmosphere, damaging the environment where many people live and work. In this study, we assessed the health effects of particles from the Kuwaiti oil fires by instilling hamsters intratracheally with particles (<3.5 microM in size) collected in Ahmadi, a residential area in Kuwait located downwind of hundreds of oil fires. Twenty-four hours after instillation, we performed bronchoalveolar lavage (BAL) to assess various indicators of pulmonary inflammation, including neutrophil and macrophage numbers; albumin, an index of air-blood barrier permeability; and activities of three enzymes: lactate dehydrogenase (LDH; an indicator of cell injury), myeloperoxidase (MPO; which indicates activation of neutrophils), and ss-N-acetylglucosaminidase (GLN; which is indicative of damage to macrophages or neutrophils). We compared the response of hamsters instilled with particles from Ahmadi to animals instilled with urban particles collected in St. Louis, Missouri. We also compared the Ahmadi particles against a highly fibrogenic positive control ([alpha]-quartz) and a relatively nontoxic negative control (iron oxide). When compared to hamsters instilled with particles from St. Louis, the animals treated with the Ahmadi particles had between 1.4- and 2.2-fold more neutrophils in their BAL fluids. The Ahmadi hamsters had more macrophages and lower MPO and LDH activities, but comparable albumin levels and GLN activities. Thus, the acute toxicity of the Ahmadi particles was roughly similar to that of urban particles collected in the United States, when identical masses were compared. However, the relatively higher concentrations of particles measured in Kuwait and Saudi Arabia during the oil fires (at times more than 16 times higher than the EPA standard) is of particular concern. In addition, since the

A biologically based model of growth and senescence of Syrian hamster embryo (SHE) cells after exposure to arsenic.

PubMed Central

Liao, K H; Gustafson, D L; Fox, M H; Chubb, L S; Reardon, K F; Yang, R S

2001-01-01

We modified the two-stage Moolgavkar-Venzon-Knudson (MVK) model for use with Syrian hamster embryo (SHE) cell neoplastic progression. Five phenotypic stages are proposed in this model: Normal cells can either become senescent or mutate into immortal cells followed by anchorage-independent growth and tumorigenic stages. The growth of normal SHE cells was controlled by their division, death, and senescence rates, and all senescent cells were converted from normal cells. In this report, we tested the modeling of cell kinetics of the first two phenotypic stages against experimental data evaluating the effects of arsenic on SHE cells. We assessed cell division and death rates using flow cytometry and correlated cell division rates to the degree of confluence of cell cultures. The mean cell death rate was approximately equal to 1% of the average division rate. Arsenic did not induce immortalization or further mutations of SHE cells at concentrations of 2 microM and below, and chromium (3.6 microM) and lead (100 microM) had similar negative results. However, the growth of SHE cells was inhibited by 5.4 microM arsenic after a 2-day exposure, with cells becoming senescent after only 16 population doublings. In contrast, normal cells and cells exposed to lower arsenic concentrations grew normally for at least 30 population doublings. The biologically based model successfully predicted the growth of normal and arsenic-treated cells, as well as the senescence rates. Mechanisms responsible for inducing cellular senescence in SHE cells exposed to arsenic may help explain the apparent inability of arsenic to induce neoplasia in experimental animals. PMID:11748027

DNA (DEOXYRIBONUCLEIC ACID) SYNTHESIS FOLLOWING MICROINJECTION OF HETEROLOGOUS SPERM AND SOMATIC CELL NUCLEI INTO HAMSTER OOCYTES

EPA Science Inventory

The authors have investigated the ability of the hamster oocyte to initiate DNA synthesis in nuclei differing in basic protein content. DNA synthesis was studied by autoradiography in oocytes that had been incubated in 3H-thymidine after being parthenogenetically activated by sha...

Acceleration of astrocytic differentiation in neural stem cells surviving X-irradiation.

PubMed

Ozeki, Ayumi; Suzuki, Keiji; Suzuki, Masatoshi; Ozawa, Hiroki; Yamashita, Shunichi

2012-03-28

Neural stem cells (NSCs) are highly susceptible to DNA double-strand breaks; however, little is known about the effects of radiation in cells surviving radiation. Although the nestin-positive NSCs predominantly became glial fibrillary acidic protein (GFAP)-positive in differentiation-permissive medium, little or no cells were GFAP positive in proliferation-permissive medium. We found that more than half of the cells surviving X-rays became GFAP positive in proliferation-permissive medium. Moreover, localized irradiation stimulated differentiation of cells outside the irradiated area. These results indicate for the first time that ionizing radiation is able to stimulate astrocyte-specific differentiation of surviving NSCs, whose process is mediated both by the direct activation of nuclear factor-κB and by the indirect bystander effect induced by X-irradiation.

Mechanisms of taste bud cell loss after head and neck irradiation.

PubMed

Nguyen, Ha M; Reyland, Mary E; Barlow, Linda A

2012-03-07

Taste loss in human patients following radiotherapy for head and neck cancer is a common and significant problem, but the cellular mechanisms underlying this loss are not understood. Taste stimuli are transduced by receptor cells within taste buds, and like epidermal cells, taste cells are regularly replaced throughout adult life. This renewal relies on progenitor cells adjacent to taste buds, which continually supply new cells to each bud. Here we treated adult mice with a single 8 Gy dose of x-ray irradiation to the head and neck, and analyzed taste epithelium at 1-21 d postirradiation (dpi). We found irradiation targets the taste progenitor cells, which undergo cell cycle arrest (1-3 dpi) and apoptosis (within 1 dpi). Taste progenitors resume proliferation at 5-7 dpi, with the proportion of cells in S and M phase exceeding control levels at 5-6 and 6 dpi, respectively, suggesting that proliferation is accelerated and/or synchronized following radiation damage. Using 5-bromo-2-deoxyuridine birthdating to identify newborn cells, we found that the decreased proliferation following irradiation reduces the influx of cells at 1-2 dpi, while the robust proliferation detected at 6 dpi accelerates entry of new cells into taste buds. In contrast, the number of differentiated taste cells was not significantly reduced until 7 dpi. These data suggest a model where continued natural taste cell death, paired with temporary interruption of cell replacement, underlies taste loss after irradiation.

Arnica Tincture Cures Cutaneous Leishmaniasis in Golden Hamsters.

PubMed

Robledo, Sara M; Vélez, Ivan D; Schmidt, Thomas J

2018-01-12

In search for potential therapeutic alternatives to existing treatments for cutaneous Leishmaniasis, we have investigated the effect of Arnica tincture Ph. Eur. (a 70% hydroethanolic tincture prepared from flowerheads of Arnica montana L.) on the lesions caused by infection with Leishmania braziliensis in a model with golden hamsters. The animals were treated topically with a daily single dose of the preparation for 28 days. Subsequently, the healing process was monitored by recording the lesion size in intervals of 15 days up to day 90. As a result, Arnica tincture fully cured three out of five hamsters while one animal showed an improvement and another one suffered from a relapse. This result was slightly better than that obtained with the positive control, meglumine antimonate, which cured two of five hamsters while the other three showed a relapse after 90 days. This result encourages us to further investigate the potential of Arnica tincture in the treatment of cutaneous Leishmaniasis.

Peripheral gustatory processing of sweet stimuli by golden hamsters.

PubMed

Frank, Marion E; Formaker, Bradley K; Hettinger, Thomas P

2005-07-15

Behaviors and taste-nerve responses to bitter stimuli are linked to compounds that bind T2 receptors expressed in one subset of taste-bud receptor cells (TRCs); and behavioral and neural responses to sweet stimuli are linked to chemical compounds that bind a T1 receptor expressed in a different TRC subset. Neural and behavioral responses to bitter-sweet mixtures, however, complicate the ostensible bitter and sweet labeled lines. In the golden hamster, Mesocricetus auratus, quinine hydrochloride, the bitter prototype, suppresses chorda tympani (CT) nerve responses to the sweet prototype: sucrose. This bitter-sweet inhibition was tested with concentration series of sucrose and dulcin, a hydrophobic synthetic sweetener that hamsters behaviorally cross-generalize with sucrose. Dulcin, sucrose and other sweeteners activate one subset of CT fibers: S neurons; whereas, quinine activates a separate subset of CT fibers: E neurons. Whole-nerve and S-neuron CT responses to a sweetener concentration series, mixed with 0, 1, 3 and 10 mM quinine, were measured for 0-2.5 s transient and/or 2.6-10 s steady-state response periods. Ten-sec total single-fiber records, aligned at response onset, were averaged for 100 ms bins to identify response oscillations. Quinine inhibition of dulcin and sucrose responses was identical. Each log molar increment in quinine resulted in equivalent declines in response to either sweetener. Furthermore, sucrose response decrements paralleled response increments in quinine-sensitive CT neurons to the same quinine increases. A 1.43 Hz bursting rhythm to the sweeteners was unchanged by quinine inhibition or decreases in sweetener concentration. Taste-bud processing, possibly between-cell inhibition and within-cell negative feedback, must modify signals initiated by T1 receptors before they are transmitted to the brain.

9 CFR 3.36 - Primary enclosures used to transport live guinea pigs and hamsters.

Code of Federal Regulations, 2011 CFR

2011-01-01

... live guinea pigs and hamsters. 3.36 Section 3.36 Animals and Animal Products ANIMAL AND PLANT HEALTH..., Care, Treatment, and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.36 Primary enclosures used to transport live guinea pigs and hamsters. No person subject to the Animal Welfare...

9 CFR 3.36 - Primary enclosures used to transport live guinea pigs and hamsters.

Code of Federal Regulations, 2010 CFR

2010-01-01

... live guinea pigs and hamsters. 3.36 Section 3.36 Animals and Animal Products ANIMAL AND PLANT HEALTH..., Care, Treatment, and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.36 Primary enclosures used to transport live guinea pigs and hamsters. No person subject to the Animal Welfare...

9 CFR 3.36 - Primary enclosures used to transport live guinea pigs and hamsters.

Code of Federal Regulations, 2014 CFR

2014-01-01

... live guinea pigs and hamsters. 3.36 Section 3.36 Animals and Animal Products ANIMAL AND PLANT HEALTH..., Care, Treatment, and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.36 Primary enclosures used to transport live guinea pigs and hamsters. No person subject to the Animal Welfare...

9 CFR 3.36 - Primary enclosures used to transport live guinea pigs and hamsters.

Code of Federal Regulations, 2013 CFR

2013-01-01

... live guinea pigs and hamsters. 3.36 Section 3.36 Animals and Animal Products ANIMAL AND PLANT HEALTH..., Care, Treatment, and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.36 Primary enclosures used to transport live guinea pigs and hamsters. No person subject to the Animal Welfare...

9 CFR 3.36 - Primary enclosures used to transport live guinea pigs and hamsters.

Code of Federal Regulations, 2012 CFR

2012-01-01

... live guinea pigs and hamsters. 3.36 Section 3.36 Animals and Animal Products ANIMAL AND PLANT HEALTH..., Care, Treatment, and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.36 Primary enclosures used to transport live guinea pigs and hamsters. No person subject to the Animal Welfare...

Irradiation at 636 nm positively affects diabetic wounded and hypoxic cells in vitro.

PubMed

Sekhejane, Palesa R; Houreld, Nicolette N; Abrahamse, Heidi

2011-08-01

This study investigated the effect of low-intensity laser irradiation (LILI) on pro-inflammatory cytokines involved in wound healing processes in diabetes and hypoxia. Diabetes is associated with impaired wound healing and a prolonged inflammatory phase. Pro-inflammatory cytokines such as interleukin (IL)-1β, tumor necrosis factor (TNF)-α and IL-6 are elevated in diabetes. LILI has been reported to accelerate wound healing and decrease inflammatory cytokines. A human skin fibroblast cell line (WS1) was used in vitro. Cells were exposed to various insults, namely, wounding, and a diabetic or hypoxic environment. Experimental cells were exposed to an energy density of 5  J/cm(2) using a continuous wave 636-nm diode laser at an average power of 95  mW, an illuminated area of 9.05  cm(2), and an irradiance of 11 mW/cm(2) (irradiation time, 476  sec). The effect of laser irradiation on cytokine expression was examined at 1 or 24  h post-irradiation. Cellular morphology, viability, proliferation, and cytokine expression (IL-1β, IL-6, and TNF-α) were investigated. Translocation of nuclear factor-kappa B (NF-κB) was also determined. There was a higher rate of migration in irradiated wounded cultures, and irradiated hypoxic cells showed an improvement in cellular morphology. All cell models showed an increase in proliferation. Normal wounded cells showed a decrease in apoptosis, TNF-α, and IL-1β. Diabetic wounded cells showed an increase in viability and a decrease in apoptosis and IL-1β, whereas hypoxic cells showed an increase in viability and IL-6, and a decrease in apoptosis and TNF-α. NF-κB was translocated into the nucleus post-irradiation. Phototherapy resulted in hastened wound closure, increased proliferation, and normalization of cellular function. The decrease in the different pro-inflammatory cytokines and NF-κB translocation was model and time dependent. Overall, laser irradiation resulted in a reduction in inflammatory cytokines and

Seasonal adaptation of dwarf hamsters (Genus Phodopus): differences between species and their geographic origin.

PubMed

Müller, D; Hauer, J; Schöttner, K; Fritzsche, P; Weinert, D

2015-12-01

The genus Phodopus consists of three species--P. campbelli (Pc), P. sungorus (Ps), and P. roborovskii (Pr). They inhabit steppes, semi-deserts, and deserts in continental Asia with a climate changing from a moderate to a hard Continental one with extreme daily and seasonal variations. These different environmental challenges are likely to have consequences for hamsters' morphology, physiology, and behavior. Hamsters of all three species were investigated during the course of the year in the laboratory though using natural lighting and temperature conditions. Motor activity and body temperature were measured continuously, and body mass, testes size, and fur coloration every 1-2 weeks. With regard to the pattern of activity, nearly twice as many Pc as Ps hamsters (25 vs. 14%) failed to respond to changes of photoperiod, whereas all Pr hamsters did. Body mass and testes size were high in summer and low in winter, with the biggest relative change in Ps and the lowest in Pr hamsters. Changes of fur coloration were found in Ps hamsters only. All responding animals (that is excluding Pr), exhibited regular torpor bouts during the short winter days. In autumn, seasonal changes started considerably earlier in Ps hamsters. To investigate the putative causes of these different time courses, a further experiment was performed, to identify the critical photoperiod. Hamsters were kept for 10 weeks under different photoperiods, changing from 16 to 8 h light per day. Motor activity was recorded continuously, to identify responding and non-responding animals. Body mass was measured at the beginning and the end of the experiment, testes mass only at the end. The critical photoperiod was found to be similar in all three species. Though in a further experiment, Pc and Pr hamsters showed a delayed response, whereas the changes in Ps hamsters started immediately following transfer to short-day conditions. The results show that interspecific differences in seasonal adaptation exist, even

Mutant Fusion Proteins with Enhanced Fusion Activity Promote Measles Virus Spread in Human Neuronal Cells and Brains of Suckling Hamsters

PubMed Central

Shirogane, Yuta; Suzuki, Satoshi O.; Ikegame, Satoshi; Koga, Ritsuko

2013-01-01

Subacute sclerosing panencephalitis (SSPE) is a fatal degenerative disease caused by persistent measles virus (MV) infection in the central nervous system (CNS). From the genetic study of MV isolates obtained from SSPE patients, it is thought that defects of the matrix (M) protein play a crucial role in MV pathogenicity in the CNS. In this study, we report several notable mutations in the extracellular domain of the MV fusion (F) protein, including those found in multiple SSPE strains. The F proteins with these mutations induced syncytium formation in cells lacking SLAM and nectin 4 (receptors used by wild-type MV), including human neuronal cell lines, when expressed together with the attachment protein hemagglutinin. Moreover, recombinant viruses with these mutations exhibited neurovirulence in suckling hamsters, unlike the parental wild-type MV, and the mortality correlated with their fusion activity. In contrast, the recombinant MV lacking the M protein did not induce syncytia in cells lacking SLAM and nectin 4, although it formed larger syncytia in cells with either of the receptors. Since human neuronal cells are mainly SLAM and nectin 4 negative, fusion-enhancing mutations in the extracellular domain of the F protein may greatly contribute to MV spread via cell-to-cell fusion in the CNS, regardless of defects of the M protein. PMID:23255801

Non-thermal cytocidal effect of infrared irradiation on cultured cancer cells using specialized device.

PubMed

Tanaka, Yohei; Matsuo, Kiyoshi; Yuzuriha, Shunsuke; Yan, Huimin; Nakayama, Jun

2010-06-01

As infrared penetrates the skin, thermal effects of infrared irradiation on cancer cells have been investigated in the field of hyperthermia. We evaluated non-thermal effects of infrared irradiation using a specialized device (1100-18000 nm with filtering of wavelengths between 1400 and 1500 nm and contact cooling) on cancer cells. In in vitro study, five kinds of cultured cancer cell lines (MCF7 breast cancer, HeLa uterine cervical cancer, NUGC-4 gastric cancer, B16F0 melanoma, and MDA-MB435 melanoma) were irradiated using the infrared device, and then the cell proliferation activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Proliferation of all the cancer cell lines was significantly suppressed by infrared irradiation. Total infrared output appeared to be correlated with cell survival. Increased temperature during infrared irradiation appeared not to play a role in cell survival. The maximum temperature elevation in the wells after each shot in the 20 and 40 J/cm(2) culture was 3.8 degrees C and 6.9 degrees C, respectively. In addition, we have shown that infrared irradiation significantly inhibited the tumor growth of MCF7 breast cancer transplanted in severe combined immunodeficiency mice and MDA-MB435 melanoma transplanted in nude mice in vivo. Significant differences between control and irradiated groups were observed in tumor volume and frequencies of TUNEL-positive and Ki-67-positive cells. These results indicate that infrared, independent of thermal energy, can induce cell killing of cancer cells. As this infrared irradiation schedule reduces discomfort and side effects, reaches the deep subcutaneous tissues, and facilitates repeated irradiations, it may have potential as an application for treating various forms of cancer.

Yellow fever 17-D vaccine is neurotropic and produces encephalitis in immunosuppressed hamsters.

PubMed

Mateo, Rosa I; Xiao, Shu-Yuan; Travassos da Rosa, Amelia P A; Lei, Hao; Guzman, Hilda; Lu, Liang; Tesh, Robert B

2007-11-01

Immunosuppressed (cyclophosphamide) adult golden hamsters inoculated intraperitoneally (i.p.) with wild-type Asibi yellow fever virus (YFV) developed a rapidly fatal illness. Histopathologic and immunohistochemical studies of tissues from these animals showed typical hepatic changes of severe yellow fever (inflammation, hepatocyte necrosis, and steatosis) without brain involvement. In contrast, 50% of immunosuppressed hamsters receiving the YFV-17D-attenuated vaccine developed a slowly progressive encephalitic-type illness. Brain tissue from these latter animals revealed focal neuronal changes, inflammation, and YFV antigen-positive neurons; however, the liver and spleen appeared normal. YFV was isolated from brain cultures of many of these animals. Immunocompetent (non-immunosuppressed) hamsters inoculated with both viruses developed a subclinical infection. Results of this study indicate that wild-type YFV is hepatotropic in immunosuppressed hamsters, whereas the attenuated YFV-17 is primarily neurotropic. These findings support current recommendations against yellow fever vaccination of immunosuppressed/immunocompromised people and suggest that this hamster model might be useful for monitoring the safety of other live-attenuated YFV vaccines.

Depopulation of the ventromedial hypothalamic nucleus in the diabetic Chinese hamster.

PubMed

Garris, D R; Diani, A R; Smith, C; Gerritsen, G C

1982-01-01

The relationship between diabetes and the size, density and area of the ventromedial hypothalamic nucleus (VMH) was studied in the genetically diabetic Chinese hamster. Matched diabetic and non-diabetic control chinese hamsters were perfused, the hypothalamus collected, sectioned and stained for light microscopy. The mid-point of each VMH nucleus was located, photographed and enlarged for morphometric analysis. Each neuron that possessed a nucleolus and was located within the confines of a VMH was counted, and subsequently the area of each nucleus and the density of neurons per area of VMH were calculated. The results indicated that both the area and absolute number of neurons within the VMH of diabetic hamsters were significantly reduced compared to control values (P less than 0.01) The density of neurons per unit area of VMH was similar in both groups. These data suggest that the VMH experiences a neuronal depopulation in diabetic hamsters which may have a functional influence on the hypothalamic-pancreatic axis in this species.

The zinc ionophore clioquinol reverses autophagy arrest in chloroquine-treated ARPE-19 cells and in APP/mutant presenilin-1-transfected Chinese hamster ovary cells.

PubMed

Seo, Bo-Ra; Lee, Sook-Jeong; Cho, Kyung Sook; Yoon, Young Hee; Koh, Jae-Young

2015-12-01

Arrested autophagy may contribute to the pathogenesis of Alzheimer's disease. Because we found that chloroquine (CQ) causes arrested autophagy but clioquinol (ClioQ), a zinc ionophore, activates autophagic flux, in the present study, we examined whether ClioQ can overcome arrested autophagy induced by CQ or mutant presenilin-1 (mPS1). CQ induced vacuole formation and cell death in adult retinal pigment epithelial (ARPE-19) cells, but co-treatment with ClioQ attenuated CQ-associated toxicity in a zinc-dependent manner. Increases in lysosome dilation and blockage of autophagic flux by CQ were also markedly attenuated by ClioQ treatment. Interestingly, CQ increased lysosomal pH in amyloid precursor protein (APP)/mPS1-expressing Chinese hamster ovary 7WΔE9 (CHO-7WΔE9) cell line, and ClioQ partially re-acidified lysosomes. Furthermore, accumulation of amyloid-β (Aβ) oligomers in CHO-7WΔE9 cells was markedly attenuated by ClioQ. Moreover, intracellular accumulation of exogenously applied fluorescein isothiocyanate-conjugated Aβ(1-42) was also increased by CQ but was returned to control levels by ClioQ. These results suggest that modulation of lysosomal functions by manipulating lysosomal zinc levels may be a useful strategy for clearing intracellular Aβ oligomers. Copyright © 2015 Elsevier Inc. All rights reserved.

New insight into mitochondrial changes in vascular endothelial cells irradiated by gamma ray.

PubMed

Hu, Shunying; Gao, Yajing; Zhou, Hao; Kong, Fanxuan; Xiao, Fengjun; Zhou, Pingkun; Chen, Yundai

2017-05-01

To investigate alterations of mitochondria in irradiated endothelial cells to further elucidate the mechanism underlying radiation-induced heart disease. Experiments were performed using human umbilical vein endothelial cells (HUVECs). HUVECs were irradiated with single gamma ray dose of 0, 5, 10 and 20 Gy, respectively. Apoptosis was assessed by flow cytometry at 24, 48 and 72 h post-irradiation, respectively. The intracellular reactive oxygen species (ROS) was measured with 2',7'-dichlorofluorescein-diacetate (DCFH-DA) at 24 h post-irradiation. Mitochondrial membrane potential (ΔΨm) by JC-1 and the opening of mitochondrial permeability transition pore (mPTP) by a calcein-cobalt quenching method were detected at 24 h post-irradiation in order to measure changes of mitochondria induced by gamma ray irradiation. Gamma ray irradiation increased HUVECs apoptosis in a dose-dependent and time-dependent manner. Irradiation also promoted ROS production in HUVECs in a dose-dependent manner. At 24 h post-irradiation, the results showed that irradiation decreases ΔΨm, however, paradoxically, flow cytometry showed green fluorescence instensity higher in irradiated HUVECs than in control HUVECs in an irradiation dose-dependent manner which indicated gamma ray irradiation inhibited mPTP opening in HUVECs. Gamma ray irradiation induces apoptosis and ROS production of endothelial cells, and decreases ΔΨm meanwhile contradictorily inhibiting the opening of mPTP.

Protective effect of enzymatic hydrolysates from highbush blueberry (Vaccinium corymbosum L.) against hydrogen peroxide-induced oxidative damage in Chinese hamster lung fibroblast cell line.

PubMed

Senevirathne, Mahinda; Kim, Soo-Hyun; Jeon, You-Jin

2010-06-01

Blueberry was enzymatically hydrolyzed using selected commercial food grade carbohydrases (AMG, Celluclast, Termamyl, Ultraflo and Viscozyme) and proteases (Alcalase, Flavourzyme, Kojizyme, Neutrase and Protamex) to obtain water soluble compounds, and their protective effect was investigated against H(2)O(2)-induced damage in Chinese hamster lung fibroblast cell line (V79-4) via various published methods. Both AMG and Alcalase hydrolysates showed higher total phenolic content as well as higher cell viability and ROS scavenging activities, and hence, selected for further antioxidant assays. Both AMG and Alcalase hydrolysates also showed higher protective effects against lipid peroxidation, DNA damage and apoptotic body formation in a dose-dependent fashion. Thus, the results indicated that water soluble compounds obtained by enzymatic hydrolysis of blueberry possess good antioxidant activity against H(2)O(2)-induced cell damage in vitro.

Model-directed engineering of "difficult-to-express" monoclonal antibody production by Chinese hamster ovary cells.

PubMed

Pybus, Leon P; Dean, Greg; West, Nathan R; Smith, Andrew; Daramola, Olalekan; Field, Ray; Wilkinson, Stephen J; James, David C

2014-02-01

Despite improvements in volumetric titer for monoclonal antibody (MAb) production processes using Chinese hamster ovary (CHO) cells, some "difficult-to-express" (DTE) MAbs inexplicably reach much lower process titers. These DTE MAbs require intensive cell line and process development activity, rendering them more costly or even unsuitable to manufacture. To rapidly and rationally identify an optimal strategy to improve production of DTE MAbs, we have developed an engineering design platform combining high-yielding transient production, empirical modeling of MAb synthesis incorporating an unfolded protein response (UPR) regulatory loop with directed expression and cell engineering approaches. Utilizing a panel of eight IgG1 λ MAbs varying >4-fold in volumetric titer, we showed that MAb-specific limitations on folding and assembly rate functioned to induce a proportionate UPR in host CHO cells with a corresponding reduction in cell growth rate. Derived from comparative empirical modeling of cellular constraints on the production of each MAb we employed two strategies to increase production of DTE MAbs designed to avoid UPR induction through an improvement in the rate/cellular capacity for MAb folding and assembly reactions. Firstly, we altered the transfected LC:HC gene ratio and secondly, we co-expressed a variety of molecular chaperones, foldases or UPR transactivators (BiP, CypB, PDI, and active forms of ATF6 and XBP1) with recombinant MAbs. DTE MAb production was significantly improved by both strategies, although the mode of action was dependent upon the approach employed. Increased LC:HC ratio or CypB co-expression improved cell growth with no effect on qP. In contrast, BiP, ATF6c and XBP1s co-expression increased qP and reduced cell growth. This study demonstrates that expression-engineering strategies to improve production of DTE proteins in mammalian cells should be product specific, and based on rapid predictive tools to assess the relative impact of

Individual differences in circadian waveform of Siberian hamsters under multiple lighting conditions

PubMed Central

Evans, Jennifer A.; Elliott, Jeffrey A.; Gorman, Michael R.

2013-01-01

Because the circadian clock in the mammalian brain derives from a network of interacting cellular oscillators, characterizing the nature and bases of circadian coupling is fundamental to understanding how the pacemaker operates. Various phenomena involving plasticity in circadian waveform have been theorized to reflect changes in oscillator coupling; however, it remains unclear whether these different behavioral paradigms reference a unitary underlying process. To test if disparate coupling assays index a common mechanism, we examined whether there is co-variation among behavioral responses to various lighting conditions that produce changes in circadian waveform. Siberian hamsters, Phodopus sungorus, were transferred from long to short photoperiods to distinguish short photoperiod responders (SP-R) from non-responders (SP-NR). Short photoperiod chronotyped hamsters were subsequently transferred, along with unselected controls, to 24 h light:dark:light:dark cycles (LDLD) with dim nighttime illumination, a procedure that induces bifurcated entrainment. Under LDLD, SP-R hamsters were more likely to bifurcate their rhythms than SP-NR hamsters or unselected controls. After transfer from LDLD to constant dim light, SP-R hamsters were also more likely to become arrhythmic compared to SP-NR hamsters and unselected controls. In contrast, short photoperiod chronotype did not influence more transient changes in circadian waveform. The present data reveal a clear relationship in the plasticity of circadian waveform across three distinct lighting conditions, suggesting a common mechanism wherein individual differences reflect variation in circadian coupling. PMID:23010663

Pineal-Induced Depression of Free Thyroxine in Syrian Hamsters

DTIC Science & Technology

1985-01-01

activation by blind- ness in Syrian hamsters, can influence free 14 concentration. MATERIALS AND METHODS Male golden hamsters, Mesocricetus auratus...considered that the changes in T4 passively result from pineal- induced hypogonadism and the possible resultant effects on T4 serum bind- ing proteins...the presence of pineal-induced hypogonadism and that, like T4 and FT41, -• ’. 328 Vaughan and Pruitt TESrE S PROSTATE 0.6 80- 20 gn Mgm ,... =_ 9 Mg_

Topical chlorophyll-pheophytin derivative-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premaligant lesions: an in vivo study

NASA Astrophysics Data System (ADS)

Hsu, Yih-Chih; Chiang, Chung-Pin; Chen, Jian Wen; Lee, Jeng-Woei; How, Mon-Hsin

2010-02-01

In Taiwan, oral cancer has become a prominent cancer because of its highest annual increase rate among all cancer diseases. Betel quid chewing habit is a major risk factor for oral precancerous and cancerous lesions and there are more than two million people who have this habit in Taiwan. Our previous studies showed that chlorophyll-pheophytin derivative (CPD)-mediated PDT is very effective for killing of SCC-4 cell lines in vitro. In order to decrease the systemic phototoxic effect of CPD, this study was designed to use a topical CPD-mediated PDT for treatment of DMBA-induced hamster buccal pouch precancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 8 to 10 weeks. Precancerous lesions of moderate to severe dysplasia were induced and proven by histological examination. These induced precancerous lesions were used for testing the efficacy of topical CPD-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when CPD reached its peak level in the lesional epithelial cells after topical application of CPD gel. We found that CPD reached its peak level in precancerous lesions about 1 hour (range, 0 to 30 hours) after topical application of CPD gel. The precancerous lesions in hamsters were then treated with topical CPD-mediated PDT (fluence rate: 200 mW/cm2; light exposure dose 100 J/cm2) using the portable WonderLight LED 635 nm fiber-guided light device once or twice a week. Visual and histological examination demonstrated that topical CPD-mediated PDT was partially effective treatment modality for DMBA-induced hamster buccal pouch precancerous lesions.

Vaccinia virus, herpes simplex virus, and carcinogens induce DNA amplification in a human cell line and support replication of a helpervirus dependent parvovirus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlehofer, J.R.; Ehrbar, M.; zur Hausen, H.

1986-07-15

The SV40-transformed human kidney cell line, NB-E, amplifies integrated as well as episomal SV40 DNA upon treatment with chemical (DMBA) or physical (uv irradiation) carcinogens (initiators) as well as after infection with herpes simplex virus (HSV) type 1 or with vaccinia virus. In addition it is shown that vaccinia virus induces SV40 DNA amplification also in the SV40-transformed Chinese hamster embryo cell line, CO631. These findings demonstrate that human cells similar to Chinese hamster cells amplify integrated DNA sequences after treatment with carcinogens or infection with specific viruses. Furthermore, a poxvirus--vaccinia virus--similar to herpes group viruses induces DNA amplification. Asmore » reported for other systems, the vaccinia virus-induced DNA amplification in NB-E cells is inhibited by coinfection with adeno-associated virus (AAV) type 5. This is in line with previous studies on inhibition of carcinogen- or HSV-induced DNA amplification in CO631 cells. The experiments also demonstrate that vaccinia virus, in addition to herpes and adenoviruses acts as a helper virus for replication and structural antigen synthesis of AAV-5 in NB-E cells.« less

A Syrian golden hamster model recapitulating ebola hemorrhagic fever.

PubMed

Ebihara, Hideki; Zivcec, Marko; Gardner, Donald; Falzarano, Darryl; LaCasse, Rachel; Rosenke, Rebecca; Long, Dan; Haddock, Elaine; Fischer, Elizabeth; Kawaoka, Yoshihiro; Feldmann, Heinz

2013-01-15

Ebola hemorrhagic fever (EHF) is a severe viral infection for which no effective treatment or vaccine is currently available. While the nonhuman primate (NHP) model is used for final evaluation of experimental vaccines and therapeutic efficacy, rodent models have been widely used in ebolavirus research because of their convenience. However, the validity of rodent models has been questioned given their low predictive value for efficacy testing of vaccines and therapeutics, a result of the inconsistent manifestation of coagulopathy seen in EHF. Here, we describe a lethal Syrian hamster model of EHF using mouse-adapted Ebola virus. Infected hamsters displayed most clinical hallmarks of EHF, including severe coagulopathy and uncontrolled host immune responses. Thus, the hamster seems to be superior to the existing rodent models, offering a better tool for understanding the critical processes in pathogenesis and providing a new model for evaluating prophylactic and postexposure interventions prior to testing in NHPs.

SU-C-204-04: Irradiation of Human Cell Lines Using Various Ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Y; McMahon, S; Kaminuma, T

2016-06-15

Purpose: The purpose of this study is to investigate and quantify the biological effects of ion radiation using several human cell lines. We aim to answer the question of whether carbon ion the most ideal ion species for heavy ion radiotherapy. Methods: The cells were irradiated at different positions along the pristine Bragg peak of several ions with different atomic number. The biological effectiveness was evaluated using the clonogenic cell survival assay. Irradiation of three human lung cancer cell lines and a fibroblast cell line were undertaken using the charged particle beam at the NASA Space Radiation Laboratory at Brookhavenmore » National Lab. Four mono-energetic ion beams (carbon, oxygen, helium and lithium) were used to irradiate the cells. Water or media-filled T25 flasks were lined up along the beam line so that the cell-containing surfaces of the flasks were placed at a specific depth along the pristine Bragg curve. Four depths along the curve, representing entrance point, rising peak, peak and distal fall off, were selected to determine biological effectiveness. Gaf-chromic films were placed between the flasks to monitor the irradiation as soon as it was finished. Results: For all ion radiations, the maximum cell killing effect occurs at either peak or distal fall off, depending on the cell lines. For instance, for the fibroblast cell line AGO1522, RBEs of 1.4, 1.2, 1.4 and 1.9 were observed at the Bragg peak for Helium, Lithium, Carbon and Oxygen ions. Comparing positions, RBEs of 0.9, 1.2, 1.4 and 1.8 were observed for carbon irradiation of AGO-1522 cells positions corresponding to entrance, rising peak, peak and distal fall off. Conclusion: RBE values differ with position in the Bragg peak, ion species and cell line. Ions other than carbon may prove more effective in certain irradiation conditions and may contribute to optimized heavy ion therapy.« less

Low- and high-dose laser irradiation effects on cell migration and destruction

NASA Astrophysics Data System (ADS)

Layton, Elivia; Gallagher, Kyra A.; Zukerman, Sara; Stevens, Brianna; Zhou, Feifan; Liu, Hong; Chen, Wei R.

2018-02-01

Metastases are the cause of more than 90 percent of cancer-related deaths. Current treatment methods, including chemotherapy, radiation, and surgery, fail to target the metastases effectively. One potential treatment for metastatic cancer is laser immunotherapy (LIT). LIT combines the use of a photothermal laser with an immunoadjuvant, Glycated Chitosan (GC). GC combined with single-walled carbon nanotubes (SWNTs) has proven to be a viable alternative to traditional cancer treatment methods, when under irradiation of laser with appropriate wavelength. In this study, the effects of low dose and high dose laser irradiation on metastatic pancreatic cancer cell migration were observed. It was found that low dose irradiation increased the migration rate, but the high dose irradiation significantly decreased the migration rate of the cancer cells. When using LIT, the goal is to kill tumor cells and to prompt the correct immune response. If the tumor were irradiated with a low dose, it would promote metastasis. If the dose of irradiation were too high, it would destroy the entire tumor and the immune response would not recognize the tumor. Therefore, the laser dose plays an important role in LIT, particularly when using SWNT as light absorbing agent. Our results from this study will delineate the optimal laser irradiation dose for destroying tumor cells and at the same time preserve and release tumor antigens as a precursor of antitumor immune response.

X-ray microbeam stand-alone facility for cultured cells irradiation

NASA Astrophysics Data System (ADS)

Bożek, Sebastian; Bielecki, Jakub; Wiecheć, Anna; Lekki, Janusz; Stachura, Zbigniew; Pogoda, Katarzyna; Lipiec, Ewelina; Tkocz, Konrad; Kwiatek, Wojciech M.

2017-03-01

The article describes an X-ray microbeam standalone facility dedicated for irradiation of living cultured cells. The article can serve as an advice for such facilities construction, as it begins from engineering details, through mathematical modeling and experimental procedures, ending up with preliminary experimental results and conclusions. The presented system consists of an open type X-ray tube with microfocusing down to about 2 μm, an X-ray focusing system with optical elements arranged in the nested Kirckpatrick-Baez (or Montel) geometry, a sample stand and an optical microscope with a scientific digital CCD camera. For the beam visualisation an X-ray sensitive CCD camera and a spectral detector are used, as well as a scintillator screen combined with the microscope. A method of precise one by one irradiation of previously chosen cells is presented, as well as a fast method of uniform irradiation of a chosen sample area. Mathematical models of beam and cell with calculations of kerma and dose are presented. The experiments on dose-effect relationship, kinetics of DNA double strand breaks repair, as well as micronuclei observation were performed on PC-3 (Prostate Cancer) cultured cells. The cells were seeded and irradiated on Mylar foil, which covered a hole drilled in the Petri dish. DNA lesions were visualised with γ-H2AX marker combined with Alexa Fluor 488 fluorescent dye.

Regulation of lipid metabolism by obeticholic acid in hyperlipidemic hamsters[S

PubMed Central

Dong, Bin; Young, Mark; Liu, Xueqing; Singh, Amar Bahadur; Liu, Jingwen

2017-01-01

The farnesoid X receptor (FXR) plays critical roles in plasma cholesterol metabolism, in particular HDL-cholesterol (HDL-C) homeostasis. Obeticholic acid (OCA) is a FXR agonist being developed for treating various chronic liver diseases. Previous studies reported inconsistent effects of OCA on regulating plasma cholesterol levels in different animal models and in different patient populations. The mechanisms underlying its divergent effects have not yet been thoroughly investigated. The scavenger receptor class B type I (SR-BI) is a FXR-modulated gene and the major receptor for HDL-C. We investigated the effects of OCA on hepatic SR-BI expression and correlated such effects with plasma HDL-C levels and hepatic cholesterol efflux in hyperlipidemic hamsters. We demonstrated that OCA induced a time-dependent reduction in serum HDL-C levels after 14 days of treatment, which was accompanied by a significant reduction of liver cholesterol content and increases in fecal cholesterol in OCA-treated hamsters. Importantly, hepatic SR-BI mRNA and protein levels in hamsters were increased to 1.9- and 1.8-fold of control by OCA treatment. Further investigations in normolipidemic hamsters did not reveal OCA-induced changes in serum HDL-C levels or hepatic SR-BI expression. We conclude that OCA reduces plasma HDL-C levels and promotes transhepatic cholesterol efflux in hyperlipidemic hamsters via a mechanism involving upregulation of hepatic SR-BI. PMID:27940481

Prevention by cromakalim of spontaneously occurring cardiac necroses in polymyopathic hamsters.

PubMed

Jasmin, G; Proschek, L

1996-11-01

Previous studies on the heart necrotizing process at early stages of the hamster polymyopathy have led us to believe that this hereditary disease derives from a defective transmembrane ion flux resulting in myocardial Ca2+ over-load. On the other hand, certain K+ ATP channel openers were shown to prevent cytosolic Ca2+ accumulation in ischemic hearts. Therefore, we investigated the potential beneficial effect of chronic treatment with cromakalim (CR) on the development of necrotic changes in hamster myopathic hearts. Young cardiomyopathic (CM) hamsters were treated parenterally with CR over 4 consecutive weeks. The K+ ATP opener was dissolved in 5% DMSO and injected twice daily (s.c. and i.p. alternatively) at a dose level of 2.5 mg/kg per injection. Microscopic readings were carried out in staged serial paraffin sections of heart ventricles, the diaphragm, and tongue, will all tissues freshly taken at autopsy. In comparison with control untreated hearts, which exhibit numerous necrotic calcific foci, only minute myolytic lesions were found in 5 of 12 hamsters hearts receiving CR (p < 0.0001). Interestingly, the dystrophic process in the tongue was significantly less severe (p < 0.0004) in CR-treated animals. These observations provide evidence for the first time that in vivo sustained treatment with a K+ ATP opener exerts cardioprotection upon development of the hamster hereditary cardiomyopathy.

Combination therapies in adjuvant with topical ALA-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premalignant lesions

NASA Astrophysics Data System (ADS)

Yang, Deng-Fu; Hsu, Yih-Chih

2012-03-01

In Taiwan, oral cancer has becomes the fastest growth male cancer disease due to the betel nut chewing habit combing with smoking and alcohol-drinking lifestyle of people. In order to eliminate the systemic phototoxic effect of 5-aminolevulinic acid (ALA), this study was designed to use a topical ALA-mediated PDT for treatment of DMBA-induced hamster buccal pouch precancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 10 to 12 weeks. Cancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical ALA-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when ALA reached its peak level in the lesional epithelial cells after topical application of ALA gel. We found that ALA reached its peak level in precancerous lesions about 2.5 hrs after topical application of ALA gel. The cancerous lesions in hamsters were then treated with topical ALA -mediated PDT with light exposure dose of 150 J/cm2 using LED 635 nm fiber-guided light device. Visual examination demonstrated that adjuvant topical ALA -mediated PDT group has shown better therapeutic results in compared to those of non-adjuvant topical ALA-mediated PDT group for DMBA-induced hamster buccal pouch precancerous lesions.

Dopamine mediates testosterone-induced social reward in male Syrian hamsters.

PubMed

Bell, Margaret R; Sisk, Cheryl L

2013-03-01

Adolescent maturation of responses to social stimuli is essential for adult-typical sociosexual behavior. Naturally occurring developmental changes in male Syrian hamster responses to a salient social cue, female hamster vaginal secretions (VS), provide a good model system for investigating neuroendocrine mechanisms of adolescent change in social reward. Sexually naïve adult, but not juvenile, males show a conditioned place preference (CPP) to VS, indicating that VS is not rewarding before puberty. In this series of experiments, the authors examined the roles of testosterone and dopamine receptor activation in mediating the adolescent gain in positive valence of VS. Experiment 1 showed that testosterone replacement is necessary for gonadectomized adult hamsters to form a CPP to VS. Experiment 2 showed that testosterone treatment is sufficient for juvenile hamsters to form a CPP to VS, and that the dopamine receptor antagonist haloperidol blocks formation of a CPP to VS in these animals. Experiments 3 and 4 demonstrated that the disruption of VS CPP with low doses of haloperidol is the result of a reduction in the attractive properties of VS and not attributable to aversive properties of haloperidol. Together, these studies demonstrate that the unconditioned rewarding properties of a social cue necessary for successful adult sociosexual interactions come about as the result of the pubertal increase in circulating testosterone in male hamsters. Furthermore, this social reward can be prevented by dopamine receptor antagonism, indicating that hypothalamic and/or mesocorticolimbic dopaminergic circuits are targets for hormonal activation of social reward.

Reaction of cells to local, regional, and general low-intensive laser irradiation

NASA Astrophysics Data System (ADS)

Baibekov, Iskander M.; Kasymov, A. S.; Musaev, Erkin S.; Vorojeikin, V. M.; Artikov, S. N.

1993-07-01

Local influence of low intensive laser irradiation (LILI) of Helium-Neon (HNL), Copper vapor (CVL), Nitrogen (UVL) and Arsenic Gallium (AGL) lasers cause stimulation of processes of physiological and reparative regeneration in intact skin, and mucous membrane of stomach and duodenum, dermatome wounds and gastroduodenal ulcers. Structural bases of these effects are the acceleration of cell proliferation and differentiation and also the activation of intracellular structures and intensification of cell secretion. Regional influence of the pointed types of LILI on hepar in cirrhosis and hepatitis causes decreasing of the inflammatory and cirrhotic changes. After endo- and exo-vascular laser irradiations of blood the decreasing of the number of pathological forms of erythrocytes and the increasing of their catalase activity, are indicated. General (total) laser irradiation of the organism--laser shower, increases the bone marrow cells proliferation, especially myeloid series. It is accompanied with acceleration of their differentiation and migration in circulation. It was revealed, that HNL to a considerable extent influences the epithelial cells and CVL the connective tissue cells. UVL increases the amount of microorganisms on cell surfaces (membrane bound microorganisms). Regional irradiation of the LILI causes both direct and indirect influence of cells. Structural changes of bone marrow cells and gut mucous membrane cells indicate intersystemic interaction.

Syrian Hamster as an Animal Model for the Study of Human Influenza Virus Infection.

PubMed

Iwatsuki-Horimoto, Kiyoko; Nakajima, Noriko; Ichiko, Yurie; Sakai-Tagawa, Yuko; Noda, Takeshi; Hasegawa, Hideki; Kawaoka, Yoshihiro

2018-02-15

Ferrets and mice are frequently used as animal models for influenza research. However, ferrets are demanding in terms of housing space and handling, whereas mice are not naturally susceptible to infection with human influenza A or B viruses. Therefore, prior adaptation of human viruses is required for their use in mice. In addition, there are no mouse-adapted variants of the recent H3N2 viruses, because these viruses do not replicate well in mice. In this study, we investigated the susceptibility of Syrian hamsters to influenza viruses with a view to using the hamster model as an alternative to the mouse model. We found that hamsters are sensitive to influenza viruses, including the recent H3N2 viruses, without adaptation. Although the hamsters did not show weight loss or clinical signs of H3N2 virus infection, we observed pathogenic effects in the respiratory tracts of the infected animals. All of the H3N2 viruses tested replicated in the respiratory organs of the hamsters, and some of them were detected in the nasal washes of infected animals. Moreover, a 2009 pandemic (pdm09) virus and a seasonal H1N1 virus, as well as one of the two H3N2 viruses, but not a type B virus, were transmissible by the airborne route in these hamsters. Hamsters thus have the potential to be a small-animal model for the study of influenza virus infection, including studies of the pathogenicity of H3N2 viruses and other strains, as well as for use in H1N1 virus transmission studies. IMPORTANCE We found that Syrian hamsters are susceptible to human influenza viruses, including the recent H3N2 viruses, without adaptation. We also found that a pdm09 virus and a seasonal H1N1 virus, as well as one of the H3N2 viruses, but not a type B virus tested, are transmitted by the airborne route in these hamsters. Syrian hamsters thus have the potential to be used as a small-animal model for the study of human influenza viruses. Copyright © 2018 American Society for Microbiology.

Proteomics analysis identified peroxiredoxin 2 involved in early-phase left ventricular impairment in hamsters with cardiomyopathy.

PubMed

Kuzuya, Kentaro; Ichihara, Sahoko; Suzuki, Yuka; Inoue, Chisa; Ichihara, Gaku; Kurimoto, Syota; Oikawa, Shinji

2018-01-01

Given the hypothesis that inflammation plays a critical role in the progression of cardiovascular diseases, the aim of the present study was to identify new diagnostic and prognostic biomarkers of myocardial proteins involved in early-phase cardiac impairment, using proteomics analysis. Using the two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) combined with MALDI-TOF/TOF tandem mass spectrometry, we compared differences in the expression of proteins in the whole left ventricles between control hamsters, dilated cardiomyopathic hamsters (TO-2), and hypertrophy cardiomyopathic hamsters (Bio14.6) at 6 weeks of age (n = 6, each group). Proteomic analysis identified 10 protein spots with significant alterations, with 7 up-regulated and 3 down-regulated proteins in the left ventricles of both TO-2 and Bio 14.6 hamsters, compared with control hamsters. Of the total alterations, peroxiredoxin 2 (PRDX2) showed significant upregulation in the left ventricles of TO-2 and Bio 14.6 hamsters. Our data suggest that PRDX2, a redox regulating molecule, is involved in early-phase left ventricular impairment in hamsters with cardiomyopathy.

Histochemical study of brown-fat cells in the golden hamster (Mesocricetus auratus) in cultures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sokolov, V.E.; Boyadzhieva-Mikhailova, A.; Koncheva, L.

1985-11-01

The authors undertake the task of studying the synthesis of certain hormones by brown-fat cells. The authors used brown-fat cells from the golden hamster. The metabolism of brown-fat cells was studied on precultured cells, which made it possible to detect the synthesis of the studied substances rather than their accumulation in the organ. The authors conducted three experiments. First, fragments of brown fat were cultivated in diffusion chambers in vivo. Pieces of brown fat were cultivated in parallel in vitro on agar (organotypic cultures) and on plasma (histotypic cultures). During cultivation in diffusion chambers, the chambers were implanted in themore » abdominal cavity of young white rats. For in vitro cultivation, TCM 199 plus 15-20% calf serum was used. A total of 36 cultures with 12 cultures in each series of experiments were performed. The auto-radiographic studies of brown-fat cells were conducted on 24-hour cultures and on brown-fat fragments taken from the intact animal. The cultures were incubated with isotopes for 1 h. Either (/sup 3/H)lysine (87.3 Ci/mM specific activity), (/sup 3/H)arginine (16.7 Ci/mM), (/sup 3/H)glycerol (43 Ci/mM), or (/sup 3/H)cholesterol (43 Ci/mM) were added to the medium. After incubation, the cultures were washed three times in pure medium, fixed in Sierra fluid, and embedded in paraffin. The paraffin sections were covered with Ilford K/sub 2/ emulsion, and the preparations were exposed for 20 days at 4/sup 0/C temperature. Radio-immunological methods were used to study the accumulation of estradiol-17-beta in the culture medium by the Dobson method and that of testerone. The culture medium was taken on cultivation days 2,4,6,8, and 10. The medium was changed during cultivation every third day, which made it possible to judge the rates of accumulation of material with increase in the cultivation times.« less

Independent regulation of periarteriolar and perivenular nitric oxide mechanisms in the in vivo hamster cheek pouch microvasculature

PubMed Central

Kim, David D.; Kanetaka, Takehito; Durán, Ricardo G.; Sánchez, Fabiola A.; Bohlen, H Glenn; Durán, Walter N.

2011-01-01

Objective We tested the hypothesis that differential stimulation of nitric oxide (NO) production can be induced in pre- and postcapillary segments of the microcirculation in the hamster cheek pouch. Methods We applied acetylcholine (ACh) or platelet-activating factor (PAF) topically and measured perivascular NO concentration ([NO]) with NO-sensitive microelectrodes in arterioles and venules of the hamster cheek pouch. We also measured NO in cultured coronary endothelial cells (CVEC) after ACh or PAF. Results ACh increased periarteriolar [NO] significantly in a dose-dependent manner. ACh at 1 μM increased [NO] from 438.1±43.4 nM at baseline to 647.9±66.3 nM, while 10 μM ACh increased [NO] from baseline to 1035.0±59.2 nM (P < 0.05). Neither 1 μM nor 10 μM ACh changed perivenular [NO] in the hamster cheek pouch. PAF, at 100 nM, increased perivenular [NO] from 326.6±50.8 nM to 622.8±41.5 nM. Importantly, 100 nM PAF did not increase periarteriolar [NO]. PAF increased [NO] from 3.6 ± 2.1 to 455.5 ± 19.9 in CVEC, while ACh had no effect. Conclusions We conclude that NO production can be stimulated in a differential manner in preand postcapillary segments in the hamster cheek pouch. ACh selectively stimulates the production of NO only in arterioles, while PAF stimulates the production of NO only in venules. PMID:19235626

Rescue of CD8+ T cell vaccine memory following sublethal γ irradiation.

PubMed

McFarland, Hugh I; Berkson, Julia D; Lee, Jay P; Elkahloun, Abdel G; Mason, Karen P; Rosenberg, Amy S

2015-07-31

Sublethal γ irradiation eliminates CD8+ T cell mediated memory responses. In this work, we explored how these memory responses could be rescued in the aftermath of such exposure. We utilized two models of CD8+ T cell mediated immunity: a mouse model of Listeria monocytogenes (LM) infection in which CD8+ T cells specific for LM expressed antigens (Listeriolysin O, LLO) can be tracked, and a murine skin graft model in which CD8+ T cells mediate rejection across a MHC class I (D(d)) disparity. In the LM immunized mice, LL0 specific CD8+ T memory cells were lost on irradiation, preserved with rapid revaccination with an attenuated strain 1-3 days post-irradiation (PI), and these mice survived a subsequent wild type LM challenge. A genetic "signature of rescue" identified a group of immune-associated mRNA maintained or upregulated following irradiation and rescue. A number of these factors, including IL-36γ, dectin-2 (Clec4n), and mir101c are upregulated rapidly after exposure of mice to sublethal γ radiation alone and are sustained by early, but not later rescue. Such factors will be evaluated as potential therapeutics to replace individual vaccines for global rescue of CD8+ T memory cell responses following sublethal γ irradiation. The skin allograft model mirrored that of the LM model in that the accelerated D(d) skin allograft rejection response was lost in mice exposed to sublethal γ radiation, but infusion of allogeneic D(d) expressing bone marrow cells 1-4 days PI preserved the CD8+ T memory mediated accelerated rejection response, further suggesting that innate immune responses may not always be essential to rescue of CD8+ memory T cells following γ irradiation. Published by Elsevier Ltd.

Ultrastructure of the filiform papillae on the tongue of the hamster.

PubMed Central

Fernandez, B; Suarez, I; Zapata, A

1978-01-01

The fine structure of the filiform papillae on the hamster tongue is described level by level from the basal layer to the surface. We did not observe two distinct types of cells with different morphology or components which could be held responsible for the production of two different types of keratin as have been described in other animals, but rather a uniformity of cell structures in each layer and only the so-called "smooth" type of keratin. However, keratin granules were more abundant in the anterior part of the papilla. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 PMID:689988

The activation of directional stem cell motility by green light-emitting diode irradiation.

PubMed

Ong, Wei-Kee; Chen, How-Foo; Tsai, Cheng-Ting; Fu, Yun-Ju; Wong, Yi-Shan; Yen, Da-Jen; Chang, Tzu-Hao; Huang, Hsien-Da; Lee, Oscar Kuang-Sheng; Chien, Shu; Ho, Jennifer Hui-Chun

2013-03-01

Light-emitting diode (LED) irradiation is potentially a photostimulator to manipulate cell behavior by opsin-triggered phototransduction and thermal energy supply in living cells. Directional stem cell motility is critical for the efficiency and specificity of stem cells in tissue repair. We explored that green LED (530 nm) irradiation directed the human orbital fat stem cells (OFSCs) to migrate away from the LED light source through activation of extracellular signal-regulated kinases (ERK)/MAP kinase/p38 signaling pathway. ERK inhibitor selectively abrogated light-driven OFSC migration. Phosphorylation of these kinases as well as green LED irradiation-induced cell migration was facilitated by increasing adenosine triphosphate (ATP) production in OFSCs after green LED exposure, and which was thermal stress-independent mechanism. OFSCs, which are multi-potent mesenchymal stem cells isolated from human orbital fat tissue, constitutionally express three opsins, i.e. retinal pigment epithelium-derived rhodopsin homolog (RRH), encephalopsin (OPN3) and short-wave-sensitive opsin 1 (OPN1SW). However, only two non-visual opsins, i.e. RRH and OPN3, served as photoreceptors response to green LED irradiation-induced OFSC migration. In conclusion, stem cells are sensitive to green LED irradiation-induced directional cell migration through activation of ERK signaling pathway via a wavelength-dependent phototransduction. Copyright © 2012 Elsevier Ltd. All rights reserved.

Irradiated KHYG-1 retains cytotoxicity: potential for adoptive immunotherapy with a natural killer cell line.

PubMed

Suck, G; Branch, D R; Keating, A

2006-05-01

To evaluate gamma-irradiation on KHYG-1, a highly cytotoxic natural killer (NK) cell line and potential candidate for cancer immunotherapy. The NK cell line KHYG-1 was irradiated at 1 gray (Gy) to 50 Gy with gamma-irradiation, and evaluated for cell proliferation, cell survival, and cytotoxicity against tumor targets. We showed that a dose of at least 10 Gy was sufficient to inhibit proliferation of KHYG-1 within the first day but not its cytolytic activity. While 50 Gy had an apoptotic effect in the first hours after irradiation, the killing of K562 and HL60 targets was not different from non-irradiated cells but was reduced for the Ph + myeloid leukemia lines, EM-2 and EM-3. gamma-irradiation (at least 10 Gy) of KHYG-1 inhibits cell proliferation but does not diminish its enhanced cytolytic activity against several tumor targets. This study suggests that KHYG-1 may be a feasible immunotherapeutic agent in the treatment of cancers.

[6]-Shogaol, a Novel Chemopreventor in 7,12-Dimethylbenz[a]anthracene-induced Hamster Buccal Pouch Carcinogenesis.

PubMed

Kathiresan, Suresh; Govindhan, Annamalai

2016-04-01

Oral cancer is a major cause of morbidity and mortality in developing countries. Despite advances in chemotherapy for the cancer management, the survival rate has not yet been improved. Dietary nutrient has been receiving a lot of attention and interest in the chemotherapeutic development. [6]-Shogaol is a major bioactive compound identified in ginger that possesses many pharmacological properties. The aim of the present study is to investigate the effect of [6]-shogaol on 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch (HBP) carcinogenesis. Oral squamous cell carcinoma induced in HBP by painting with 0.5% 7,12-dimethylbenz(a)anthracene (DMBA), thrice in a week for 16 weeks. We observed 100% tumour incidence, decreased levels of lipid peroxidation, antioxidant, and phase II detoxification enzymes (GST, GR and GSH) in DMBA-induced hamsters. Further, enhanced activity of phase I enzymes (cytochrome p450 and b5) and over-expression of mutant p53, Bcl-2 and decreased expression of wild type p53 and Bax were noticed in DMBA-induced hamsters. Our results indicated that [6]-shogaol (10, 20 and 40 mg/kg body weight) treated with DMBA-painted hamsters, considerably reversed tumour incidence, improved antioxidant status, phase II detoxification enzymes, and also inhibit lipid peroxidation and phase I enzymes. Moreover, [6]-shogaol inhibits mutant p53 and Bcl-2 expression and significantly restored normal p53, Bax levels. Thus, we concluded that [6]-shogaol prevents DMBA-induced HBP carcinogenesis through its antioxidant as well as modulating apoptotic signals. Copyright © 2016 John Wiley & Sons, Ltd.

Selective retension of active cells employing low centrifugal force at the medium change during suspension culture of Chinese hamster ovary cells producing tPA.

PubMed

Takagi, M; Ilias, M; Yoshida, T

2000-01-01

The effect of centrifugal force applied for cell separation at the medium change on the growth, metabolism and tissue plasminogen activator (tPA) productivity of Chinese hamster ovary (CHO) cells suspension culture was investigated. The viability of the precipitated cells increased exponentially as the centrifugal force decreased. However, the cell recovery was lower than 91% when centrifugal forces applied for 5 min was less than 67 x g. In cultures incubated for 474 h with 7 medium changes employing centrifugal forces ranging from 67 to 364 x g, a centrifugal force lower than 119 x g resulted in higher specific rates of growth, glucose consumption, and lactate and tPA production during the whole culture period. On the other hand, daily centrifugation at 67 to 537 x g without discarding the supernatant had no effect on the specific rates. The cultures inoculated with cells precipitated at a centrifugal force of 67 x g showed apparently higher specific rates of metabolism compared to those inoculated with cells in the supernatant. The cells in the supernatant and the precipitate obtained following centrifugation at 67 x g have average diameters of 15.5 and 17.4 microm, respectively. The intracellular contents of amino acids, especially nonessential amino acids, of the precipitated cells were markedly higher than those of the cells in the supernatant. These results indicate that large cells with high amino acid content and metabolic activity were selectively retained in the culture by means of centrifugation at low forces such as 67 x g. Consequently, application of a low centrifugal force is recommended for medium change in order to maintain higher specific productivity of suspended mammalian cells in perfusion culture.

A Syrian Golden Hamster Model Recapitulating Ebola Hemorrhagic Fever

PubMed Central

Ebihara, Hideki; Zivcec, Marko; Gardner, Donald; Falzarano, Darryl; LaCasse, Rachel; Rosenke, Rebecca; Long, Dan; Haddock, Elaine; Fischer, Elizabeth; Kawaoka, Yoshihiro; Feldmann, Heinz

2013-01-01

Ebola hemorrhagic fever (EHF) is a severe viral infection for which no effective treatment or vaccine is currently available. While the nonhuman primate (NHP) model is used for final evaluation of experimental vaccines and therapeutic efficacy, rodent models have been widely used in ebolavirus research because of their convenience. However, the validity of rodent models has been questioned given their low predictive value for efficacy testing of vaccines and therapeutics, a result of the inconsistent manifestation of coagulopathy seen in EHF. Here, we describe a lethal Syrian hamster model of EHF using mouse-adapted Ebola virus. Infected hamsters displayed most clinical hallmarks of EHF, including severe coagulopathy and uncontrolled host immune responses. Thus, the hamster seems to be superior to the existing rodent models, offering a better tool for understanding the critical processes in pathogenesis and providing a new model for evaluating prophylactic and postexposure interventions prior to testing in NHPs. PMID:23045629

Preliminary Low Temperature Electron Irradiation of Triple Junction Solar Cells

NASA Technical Reports Server (NTRS)

Stella, Paul M.; Mueller, Robert L.; Scrivner, Roy L.; Helizon, Roger S.

2007-01-01

For many years extending solar power missions far from the sun has been a challenge not only due to the rapid falloff in solar intensity (intensity varies as inverse square of solar distance) but also because some of the solar cells in an array may exhibit a LILT (low intensity low temperature) degradation that reduces array performance. Recent LILT tests performed on commercial triple junction solar cells have shown that high performance can be obtained at solar distances as great as approx. 5 AU1. As a result, their use for missions going far from the sun has become very attractive. One additional question that remains is whether the radiation damage experienced by solar cells under low temperature conditions will be more severe than when measured during room temperature radiation tests where thermal annealing may take place. This is especially pertinent to missions such as the New Frontiers mission Juno, which will experience cell irradiation from the trapped electron environment at Jupiter. Recent testing2 has shown that low temperature proton irradiation (10 MeV) produces cell degradation results similar to room temperature irradiations and that thermal annealing does not play a factor. Although it is suggestive to propose the same would be observed for low temperature electron irradiations, this has not been verified. JPL has routinely performed radiation testing on commercial solar cells and has also performed LILT testing to characterize cell performance under far sun operating conditions. This research activity was intended to combine the features of both capabilities to investigate the possibility of any room temperature annealing that might influence the measured radiation damage. Although it was not possible to maintain the test cells at a constant low temperature between irradiation and electrical measurements, it was possible to obtain measurements with the cell temperature kept well below room temperature. A fluence of 1E15 1MeV electrons was

Iron ion irradiation increases promotes adhesion of monocytic cells to arterial vascular endothelium

NASA Astrophysics Data System (ADS)

Kucik, Dennis; Khaled, Saman; Gupta, Kiran; Wu, Xing; Yu, Tao; Chang, Polly; Kabarowski, Janusz

Radiation causes inflammation, and chronic, low-level vascular inflammation is a risk factor for atherosclerosis. Consistent with this, exposure to radiation from a variety of sources is associated with increased risk of heart disease and stroke. Part of the inflammatory response to radiation is a change in the adhesiveness of the endothelial cells that line the blood vessels, triggering inappropriate accumulation of leukocytes, leading to later, damaging effects of inflammation. Although some studies have been done on the effects of gamma irradiation on vascular endothelium, the response of endothelium to heavy ion radiation likely to be encountered in prolonged space flight has not been determined. We investigated how irradiation of aortic endothelial cells with iron ions affects adhesiveness of cultured aortic endothelial cells for monocytic cells and the consequences of this for development of atherosclerosis. Aortic endothelial cells were irradiated with 600 MeV iron ions at Brookhaven National Laboratory and adhesion-related changes were measured. Cells remained viable for at least 72 hours, and were even able to repair acute damage to cell junctions. We found that iron ion irradiation altered expression levels of specific endothelial cell adhesion molecules. Further, these changes had functional consequences. Using a flow chamber adhesion assay to measure adhesion of monocytic cells to endothelial cells under physiological shear stress, we found that adhesivity of vascular endothelium was enhanced in as little as 24 hours after irradiation. Further, the radiation dose dependence was not monotonic, suggesting that it was not simply the result of endothelial cell damage. We also irradiated aortic arches and carotid arteries of Apolipoprotein-E-deficient mice. Histologic analysis of these mice will be conducted to determine whether effects of radiation on endothelial adhesiveness result in consequences for development of atherosclerosis. (Supported by NSBRI

Protective effect of enzymatic hydrolysates from highbush blueberry (Vaccinium corymbosum L.) against hydrogen peroxide-induced oxidative damage in Chinese hamster lung fibroblast cell line

PubMed Central

Senevirathne, Mahinda; Kim, Soo-Hyun

2010-01-01

Blueberry was enzymatically hydrolyzed using selected commercial food grade carbohydrases (AMG, Celluclast, Termamyl, Ultraflo and Viscozyme) and proteases (Alcalase, Flavourzyme, Kojizyme, Neutrase and Protamex) to obtain water soluble compounds, and their protective effect was investigated against H2O2-induced damage in Chinese hamster lung fibroblast cell line (V79-4) via various published methods. Both AMG and Alcalase hydrolysates showed higher total phenolic content as well as higher cell viability and ROS scavenging activities, and hence, selected for further antioxidant assays. Both AMG and Alcalase hydrolysates also showed higher protective effects against lipid peroxidation, DNA damage and apoptotic body formation in a dose-dependent fashion. Thus, the results indicated that water soluble compounds obtained by enzymatic hydrolysis of blueberry possess good antioxidant activity against H2O2-induced cell damage in vitro. PMID:20607062

[Purification of arsenic-binding proteins in hamster plasma after oral administration of arsenite].

PubMed

Wang, Wenwen; Zhang, Min; Li, Chunhui; Qin, Yingjie; Hua, Naranmandura

2013-01-01

To purify the arsenic-binding proteins (As-BP) in hamster plasma after a single oral administration of arsenite (iAs(III)). Arsenite was given to hamsters in a single dose. Three types of HPLC columns, size exclusion, gel filtration and anion exchange columns, combined with an inductively coupled argon plasma mass spectrometer (ICP MS) were used to purify the As-BP in hamster plasma. SDS-PAGE was used to confirm the arsenic-binding proteins at each purification step. The three-step purification process successfully separated As-BP from other proteins (ie, arsenic unbound proteins) in hamster plasma. The molecular mass of purified As-BP in plasma was approximately 40-50 kD on SDS-PAGE. The three-step purification method is a simple and fast approach to purify the As-BP in plasma samples.

Role of photoperiod and melatonin in seasonal acclimatization of the djungarian hamster, Phodopus sungorus

NASA Astrophysics Data System (ADS)

Steinlechner, S.; Heldmaier, G.

1982-12-01

The Djungarian hamster, Phodopus sungorus, shows a clear annual cycle in some thermogenic parameters such as nonshivering thermogenesis (NST) and cold resistance. These seasonal changes were found to be basically controlled by natural changes in photoperiod. Further support for this view was obtained by exposing the hamsters to artificial long and short photoperiods. Implantation of melatonin during fall and winter results in an increased thermogenic capacity in both short and long day hamsters comparable to that shown by values of control hamsters exposed to short photoperiods during winter. This thermotropic action of melatonin and of short photoperiod could be found only in fall and winter whereas during spring and summer, melatonin, like photoperiod, had no influence on thermogenic capacities. These results show that the actions of melatonin and photoperiod vary with the season and that they depend upon the photoperiodic history of the hamsters. Our results further indicate that the pineal gland with its hormone melatonin is involved in mediation of photoperiodic control of seasonal acclimatization.

Sweet taste transduction in hamster: sweeteners and cyclic nucleotides depolarize taste cells by reducing a K+ current.

PubMed

Cummings, T A; Daniels, C; Kinnamon, S C

1996-03-01

1. The gigaseal voltage-clamp technique was used to record responses of hamster taste receptor cells to synthetic sweeteners and cyclic nucleotides. Voltage-dependent currents and steady-state currents were monitored during bath exchanges of saccharin, two high-potency sweeteners, 8-chlorophenylthio-adenosine 3',5'-cyclic monophosphate (8cpt-cAMP), and dibutyryl-guanosine 3',5'-cyclic monophosphate (db-cGMP). 2. Of the 237 fungiform taste cells studied, only one in eight was sweet responsive. Outward currents, both voltage-dependent and resting, were reduced by all of the sweeteners tested in sweet-responsive taste cells, whereas these currents were unaffected by sweeteners in sweet-unresponsive taste cells. 3. In every sweet-responsive cell tested, 8cpt-cAMP and db-cGMP mimicked the response to the sweeteners, but neither nucleotide elicited responses in sweet-unresponsive cells. Thus there was a one-to-one correlation between sweet responsivity and cyclic nucleotide responsivity. 4. Sweet responses showed cross adaptation with cyclic nucleotide responses. This indicates that the same ion channel is modulated by sweeteners and cyclic nucleotides. 5. The sweetener- and cyclic nucleotide-blocked current had an apparent reversal potential of -50 mV, which was close to the potassium reversal potential in these experiments. In addition, there was no effect of sweeteners and cyclic nucleotides in the presence of the K+ channel blocker tetraethylammonium bromide (TEA). These data suggest that block of a resting, TEA-sensitive K+ current is the final common step leading to taste cell depolarization during sweet transduction. 6. These data, together with data from a previous study (Cummings et al. 1993), suggest that both synthetic sweeteners and sucrose utilize second-messenger pathways that block a resting K+ conductance to depolarize the taste cell membrane.

The calculated influence of atmospheric conditions on solar cell ISC under direct and global solar irradiances

NASA Technical Reports Server (NTRS)

Mueller, Robert L.

1987-01-01

Calculations of the influence of atmospheric conditions on solar cell short-circuit current (Isc) are made using a recently developed computer model for solar spectral irradiance distribution. The results isolate the dependence of Isc on changes in the spectral irradiance distribution without the direct influence of the total irradiance level. The calculated direct normal irradiance and percent diffuse irradiance are given as a reference to indicate the expected irradiance levels. This method can be applied to the calibration of photovoltaic reference cells. Graphic examples are provided for amorphous silicon and monocrystalline silicon solar cells under direct normal and global normal solar irradiances.

Comparison of Bacterial Burden and Cytokine Gene Expression in Golden Hamsters in Early Phase of Infection with Two Different Strains of Leptospira interrogans.

PubMed

Fujita, Rie; Koizumi, Nobuo; Sugiyama, Hiromu; Tomizawa, Rina; Sato, Ryoichi; Ohnishi, Makoto

2015-01-01

Leptospirosis, a zoonotic infection with worldwide prevalence, is caused by pathogenic spirochaetes of Leptospira spp., and exhibits an extremely broad clinical spectrum in human patients. Although previous studies indicated that specific serovars or genotypes of Leptospira spp. were associated with severe leptospirosis or its outbreak, the mechanism underlying the difference in virulence of the various Leptospira serotypes or genotypes remains unclear. The present study addresses this question by measuring and comparing bacterial burden and cytokine gene expression in hamsters infected with strains of two L. interrogans serovars Manilae (highly virulent) and Hebdomadis (less virulent). The histopathology of kidney, liver, and lung tissues was also investigated in infected hamsters. A significantly higher bacterial burden was observed in liver tissues of hamsters infected with serovar Manilae than those infected with serovar Hebdomadis (p < 0.01). The average copy number of the leptospiral genome was 1,302 and 20,559 in blood and liver, respectively, of hamsters infected with serovar Manilae and 1,340 and 4,896, respectively, in hamsters infected with serovar Hebdomadis. The expression levels of mip1alpha in blood; tgfbeta, il1beta, mip1alpha, il10, tnfalpha and cox2 in liver; and tgfbeta, il6, tnfalpha and cox2 in lung tissue were significantly higher in hamsters infected with serovar Manilae than those infected with serovar Hebdomadis (p < 0.05). In addition, infection with serovar Manilae resulted in a significantly larger number of hamsters with tnfalpha upregulation (p = 0.04). Severe distortion of tubular cell arrangement and disruption of renal tubules in kidney tissues and hemorrhage in lung tissues were observed in Manilae-infected hamsters. These results demonstrate that serovar Manilae multiplied more efficiently in liver tissues and induced significantly higher expression of genes encoding pro- and anti-inflammatory cytokines than serovar Hebdomadis

Comparison of Bacterial Burden and Cytokine Gene Expression in Golden Hamsters in Early Phase of Infection with Two Different Strains of Leptospira interrogans

PubMed Central

Fujita, Rie; Koizumi, Nobuo; Sugiyama, Hiromu; Tomizawa, Rina; Sato, Ryoichi; Ohnishi, Makoto

2015-01-01

Leptospirosis, a zoonotic infection with worldwide prevalence, is caused by pathogenic spirochaetes of Leptospira spp., and exhibits an extremely broad clinical spectrum in human patients. Although previous studies indicated that specific serovars or genotypes of Leptospira spp. were associated with severe leptospirosis or its outbreak, the mechanism underlying the difference in virulence of the various Leptospira serotypes or genotypes remains unclear. The present study addresses this question by measuring and comparing bacterial burden and cytokine gene expression in hamsters infected with strains of two L. interrogans serovars Manilae (highly virulent) and Hebdomadis (less virulent). The histopathology of kidney, liver, and lung tissues was also investigated in infected hamsters. A significantly higher bacterial burden was observed in liver tissues of hamsters infected with serovar Manilae than those infected with serovar Hebdomadis (p < 0.01). The average copy number of the leptospiral genome was 1,302 and 20,559 in blood and liver, respectively, of hamsters infected with serovar Manilae and 1,340 and 4,896, respectively, in hamsters infected with serovar Hebdomadis. The expression levels of mip1alpha in blood; tgfbeta, il1beta, mip1alpha, il10, tnfalpha and cox2 in liver; and tgfbeta, il6, tnfalpha and cox2 in lung tissue were significantly higher in hamsters infected with serovar Manilae than those infected with serovar Hebdomadis (p < 0.05). In addition, infection with serovar Manilae resulted in a significantly larger number of hamsters with tnfalpha upregulation (p = 0.04). Severe distortion of tubular cell arrangement and disruption of renal tubules in kidney tissues and hemorrhage in lung tissues were observed in Manilae-infected hamsters. These results demonstrate that serovar Manilae multiplied more efficiently in liver tissues and induced significantly higher expression of genes encoding pro- and anti-inflammatory cytokines than serovar Hebdomadis

Efficient expression of stable recombinant human insulin-like growth factor-1 fusion with human serum albumin in Chinese hamster ovary cells.

PubMed

Wan, Aini; Xu, Dongsheng; Liu, Kedong; Peng, Lin; Cai, Yanfei; Chen, Yun; He, Yang; Yang, Jianfeng; Jin, Jian; Li, Huazhong

2017-08-09

Insulin-like growth factor-1 (IGF-1) plays a crucial role in cell development, differentiation, and metabolism, and has been a potential therapeutic agent for many diseases. Chinese hamster ovary (CHO) cells are widely used for production of recombinant therapeutic proteins, but the expression level of IGF-1 in CHO cells is very low (1,500 µg/L) and the half-life of IGF-1 in blood circulation is only 4.5 min according to previous studies. Therefore, IGF-1 was fused to long-circulating serum protein human serum albumin (HSA) and expressed in CHO cells. After 8-day fed-batch culture, the expression level of HSA-IGF-1 reached 100 mg/L. The fusion protein HSA-IGF-1 was purified with a recovery of 35% using a two-step chromatographic procedure. According to bioactivity assay, the purified HSA-IGF-1 could stimulate the proliferation of NIH3T3 cells in a dose-dependent fashion and promote the cell-cycle progression. Besides this, HSA-IGF-1 could bind to IGF-1 receptor on cell membrane and activate the intracellular PI3K/AKT signaling pathway. Our study suggested that HSA fusion technology carried out in CHO cells not only provided bioactivity in HSA-IGF-1 for further research but also offered a beneficial strategy to produce other similar cytokines in CHO cells.

A new species of Giardia Künstler, 1882 (Sarcomastigophora: Hexamitidae) in hamsters.

PubMed

Lyu, Zhangxia; Shao, Jingru; Xue, Min; Ye, Qingqing; Chen, Bing; Qin, Yan; Wen, Jianfan

2018-03-20

Giardia spp. are flagellated protozoan parasites that infect humans and many other vertebrates worldwide. Currently seven species of Giardia are considered valid. Here, we report a new species, Giardia cricetidarum n. sp. in hamsters. Trophozoites of G. cricetidarum n. sp. are pear-shaped with four pairs of flagella and measure on average 14 μm (range 12-18 μm) in length and 10 μm (range 8-12 μm) in width. The trophozoites of the new species are generally larger and stouter than those of most of the other Giardia spp. and exhibit the lowest length/width ratio (c.1.40) of all recognized Giardia species. Cysts of G. cricetidarum n. sp. are ovoid and measure on average 11 μm (range 9-12 μm) in length and 10 μm (range 8-10 μm) in width and are indistinguishable from the cysts of other Giardia species. Molecular phylogenetic analyses based on beta-giardin, small subunit rRNA, and elongation factor-1 alpha loci all demonstrated that G. cricetidarum n. sp. is genetically distinct from all currently accepted Giardia spp. Investigation of the host range indicated that the new species was only found in hamsters (including Phodopus sungorus, P. campbelli and Mesocricetus auratus), while all the other described mammal-parasitizing species (G. muris, G. microti and G. intestinalis) each infect multiple hosts. Cross-transmission studies further demonstrated the apparent host specificity of G. cricetidarum n. sp. as it only infected hamsters. Trophozoites were found in high numbers in hamster intestines (5 × 10 5 - 5 × 10 6 ) and was rarely detected co-infecting with other Giardia spp. in the common hamster, suggesting it has some advantages in parasitizing hamsters. This study has identified a new species of Giardia, which appears to be specific to hamsters, and together with the three other mammal-parasitizing Giardia species with different host ranges, may be able to be used as a model system for the study of evolutionary divergence of host parasitism strategies in

Apoptosis and proliferation of oligodendrocyte progenitor cells in the irradiated rodent spinal cord

DOE Office of Scientific and Technical Information (OSTI.GOV)

Atkinson, Shelley L.; Li Yuqing; Wong, C. Shun

2005-06-01

Purpose: Oligodendrocytes undergo early apoptosis after irradiation. The aim of this study was to determine the relationship between oligodendroglial apoptosis and proliferation of oligodendrocyte progenitor cells (OPC) in the irradiated central nervous system. Methods and Materials: Adult rats and p53 transgenic mice were given single doses of 2 Gy, 8 Gy, or 22 Gy to the cervical spinal cord. Apoptosis was assessed using TUNEL (Tdt-mediated dUTP terminal nick-end labeling) staining or by examining nuclear morphology. Oligodendrocyte progenitor cells were identified with an NG2 antibody or by in situ hybridization for platelet-derived growth factor receptor {alpha}. Proliferation of OPC was assessedmore » by in vivo bromodeoxyuridine (BrdU) labeling and subsequent immunohistochemistry. Because radiation-induced apoptosis of oligodendroglial cells is p53 dependent, p53 transgenic mice were used to study the relationship between apoptosis and cell proliferation. Results: Oligodendrocyte progenitor cells underwent apoptosis within 24 h of irradiation in the rat. That did not result in a change in OPC density at 24 h. Oligodendrocyte progenitor cell density was significantly reduced by 2-4 weeks, but showed recovery by 6 weeks after irradiation. An increase in BrdU-labeled cells was observed at 2 weeks after 8 Gy or 22 Gy, and proliferating cells in the rat spinal cord were immunoreactive for NG2. The mouse spinal cord showed a similar early cell proliferation after irradiation. No difference was observed in the proliferation response in the spinal cord of p53 -/- mice compared with wild type animals. Conclusions: Oligodendroglial cells undergo early apoptosis and OPC undergo early proliferation after ionizing radiation. However, apoptosis is not likely to be the trigger for early proliferation of OPC in the irradiated central nervous system.« less

Reversion of 6-thioguanine resistant Chinese hamster cell lines: agent specificity and evidence for the repair of promutagenic lesions.

PubMed

Hodgkiss, R J; Brennand, J; Fox, M

1980-02-01

The kinetics and mutagen specificity of reversion of an HGPRT(-)TG(R) line of Chinese hamster cells have been examined in detail by measuring the frequency of HAT(R) colonies. Alkylating agents which produce relatively high levels of O-atom reaction were effective in inducing reversion. MMS, DMS and u.v. were less efficient, and aflatoxin B1, acridine orange and N-acetoxy-AAF were completely ineffective. For agents which were effective, the relationship between HAT(R) colony frequency and dose of mutagen was linear at early expression times (6 h). HAT(R) colony frequency fell subsequently at all doses and the rate and extent of the fall was inversely related to dose. These observations suggest repair of a pro-mutagenic DNA lesion. Other TG(R) mutants isolated from the same wild-type cell line under different selective conditions were also tested for revertibility after exposure to the same mutagens. The majority did not revert, this suggests that they carry deletions within the structural gene for HGPRT. The infrequent revertible lines all arose spontaneously and our evidence suggests that they carry nonsense mutations.

Low-intensity laser irradiation at 660 nm stimulates cytochrome c oxidase in stressed fibroblast cells.

PubMed

Houreld, Nicolette N; Masha, Roland T; Abrahamse, Heidi

2012-07-01

Low-intensity laser irradiation (LILI) has been used to modulate a variety of biological processes, including diabetic wound healing. The mechanism of action is thought to exist primarily with the mitochondria. This study aimed to determine the effect of irradiation on normal, diabetic, and ischemic mitochondrial electron transport chain (ETC) complexes. Normal, diabetic and ischemic human skin fibroblast mitochondria were irradiated in vitro at a wavelength of 660 nm and a fluence of either 5 or 15 J/cm(2). Non-irradiated mitochondria served as controls. Enzyme activities of mitochondrial complexes I, II, III, and IV were determined immediately post-irradiation. Normal, diabetic, and ischemic cells were irradiated and adenosine triphosphate (ATP) and active mitochondria were determined by luminescence and fluorescent microscopy, respectively. Irradiated diabetic mitochondria at a fluence of 15 J/cm(2) showed a significant decrease in complex III activity (P < 0.05). Normal (P < 0.01) and diabetic (P < 0.05) mitochondria irradiated at either 5 or 15 J/cm(2) showed a significant increase in complex IV activity. ATP results showed a significant increase in irradiated normal cells (5 J/cm(2); P < 0.05) and diabetic cells (15 J/cm(2); P < 0.01). There was a higher accumulation of active mitochondria in irradiated cells than non-irradiated cells. Irradiation at 660 nm has the ability to influence mitochondrial enzyme activity, in particular cytochrome c oxidase. This leads to increased mitochondrial activity and ATP synthesis. Copyright © 2012 Wiley Periodicals, Inc.

A Comparison of Hamster Anesthetics and Their Effect on Mosquito Blood Feeding

USDA-ARS?s Scientific Manuscript database

Hamsters or mice are often anesthetized when they are used as the hosts for insect feeding experiments. An experiment was done to determine if there was a difference in mosquito blood feeding success when fed on hamsters anesthetized using two commonly used protocols. The number of blood-fed females...

The pathophysiology of human obstructive cholestasis is mimicked in cholestatic Gold Syrian hamsters.

PubMed

van Golen, Rowan F; Olthof, Pim B; de Haan, Lianne R; Coelen, Robert J; Pechlivanis, Alexandros; de Keijzer, Mark J; Weijer, Ruud; de Waart, Dirk R; van Kuilenburg, André B P; Roelofsen, Jeroen; Gilijamse, Pim W; Maas, Martinus A; Lewis, Matthew R; Nicholson, Jeremy K; Verheij, Joanne; Heger, Michal

2018-03-01

Obstructive cholestasis causes liver injury via accumulation of toxic bile acids (BAs). Therapeutic options for cholestatic liver disease are limited, partially because the available murine disease models lack translational value. Profiling of time-related changes following bile duct ligation (BDL) in Gold Syrian hamsters revealed a biochemical response similar to cholestatic patients in terms of BA pool composition, alterations in hepatocyte BA transport and signaling, suppression of BA production, and adapted BA metabolism. Hamsters tolerated cholestasis well for up to 28days and progressed relatively slowly to fibrotic liver injury. Hepatocellular necrosis was absent, which coincided with preserved intrahepatic energy levels and only mild oxidative stress. The histological response to cholestasis in hamsters was similar to the changes seen in 17 patients with prolonged obstructive cholestasis caused by cholangiocarcinoma. Hamsters moreover upregulated hepatic fibroblast growth factor 15 (Fgf15) expression in response to BDL, which is a cytoprotective adaptation to cholestasis that hitherto had only been documented in cholestatic human livers. Hamster models should therefore be added to the repertoire of animal models used to study the pathophysiology of cholestatic liver disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of wheel running on chronic ethanol intake in aged Syrian hamsters.

PubMed

Brager, Allison J; Hammer, Steven B

2012-10-10

Alcohol dependence in aging populations is seen as a public health concern, most recently because of the significant proportion of heavy drinking among "Baby Boomers." Basic animal research on the effects of aging on physiological and behavioral regulation of ethanol (EtOH) intake is sparse, since most of this research is limited to younger models of alcoholism. Here, EtOH drinking and preference were measured in groups of aged Syrian hamsters. Further, because voluntary exercise (wheel-running) is a rewarding substitute for EtOH in young adult hamsters, the potential for such reward substitution was also assessed. Aged (24 month-old) male hamsters were subjected to a three-stage regimen of free-choice EtOH (20% v/v) or water and unlocked or locked running wheels to investigate the modulatory effects of voluntary wheel running on EtOH intake and preference. Levels of fluid intake and activity were recorded daily across 60 days of experimentation. Prior to wheel running, levels of EtOH intake were significantly less than levels of water intake, resulting in a low preference for EtOH (30%). Hamsters with access to an unlocked running wheel had decreased EtOH intake and preference compared with hamsters with access to a locked running wheel. These group differences in EtOH intake and preference were sustained for up to 10 days after running wheels were re-locked. These results extend upon those of our previous work in young adult hamsters, indicating that aging dampens EtOH intake and preference. Voluntary wheel running further limited EtOH intake, suggesting that exercise could offer a practical approach for managing late-life alcoholism. Copyright © 2012 Elsevier Inc. All rights reserved.

Cell performance and defect behavior in proton-irradiated lithium-counterdoped n(+)p silicon solar cells

NASA Technical Reports Server (NTRS)

Weinberg, I.; Stupica, J. W.; Swartz, C. K.; Goradia, C.

1986-01-01

Lithium-counterdoped n(+)p silicon solar cells were irradiated by 10-MeV protons, and their performance was determined as a function of fluence. It was found that the cell with the highest lithium concentration exhibited the higher radiation resistance. Deep-level transient spectroscopy studies of deep-level defects were used to identify two lithium-related defects. Defect energy levels obtained after the present 10-MeV irradiations were found to be markedly different than those observed after previous 1-MeV electron irradiations. However, the present DLTS data are consistent with previous suggestion by Weinberg et al. (1984) of a lithium-oxygen interaction which tends to inhibit formation of an interstitial boron-oxygen defect.

Acute encephalitis, a poliomyelitis-like syndrome and neurological sequelae in a hamster model for flavivirus infections.

PubMed

Leyssen, Pieter; Croes, Romaric; Rau, Philipp; Heiland, Sabine; Verbeken, Erik; Sciot, Raphael; Paeshuyse, Jan; Charlier, Nathalie; De Clercq, Erik; Meyding-Lamadé, Uta; Neyts, Johan

2003-07-01

Infection of hamsters with the murine flavivirus Modoc results in (meningo)encephalitis, which is, during the acute phase, frequently associated with flaccid paralysis, as also observed in patients with West Nile virus encephalitis. Twenty percent of the hamsters that recover from the acute encephalitis develop life-long neurological sequelae, reminiscent of those observed, for example, in survivors of Japanese encephalitis. Magnetic resonance imaging and histology revealed severe lesions predominantly located in the olfactory-limbic system, both in hamsters with acute encephalitis as in survivors. Prominent pathology was also detected in the spinal cord of hamsters with paralysis. Modoc virus infections in hamsters provide a unique model for the study of encephalitis, a poliomyelitis-like syndrome and neurological sequelae following flavivirus infection.

Long-term cognitive effects of human stem cell transplantation in the irradiated brain.

PubMed

Acharya, Munjal M; Martirosian, Vahan; Christie, Lori-Ann; Limoli, Charles L

2014-09-01

Radiotherapy remains a primary treatment modality for the majority of central nervous system tumors, but frequently leads to debilitating cognitive dysfunction. Given the absence of satisfactory solutions to this serious problem, we have used human stem cell therapies to ameliorate radiation-induced cognitive impairment. Here, past studies have been extended to determine whether engrafted cells provide even longer-term benefits to cognition. Athymic nude rats were cranially irradiated (10 Gy) and subjected to intrahippocampal transplantation surgery 2 days later. Human embryonic stem cells (hESC) or human neural stem cells (hNSC) were transplanted, and animals were subjected to cognitive testing on a novel place recognition task 8 months later. Grafting of hNSC was found to provide long lasting cognitive benefits over an 8-month post-irradiation interval. At this protracted time, hNSC grafting improved behavioral performance on a novel place recognition task compared to irradiated animals not receiving stem cells. Engrafted hESC previously shown to be beneficial following a similar task, 1 and 4 months after irradiation, were not found to provide cognitive benefits at 8 months. Our findings suggest that hNSC transplantation promotes the long-term recovery of the irradiated brain, where intrahippocampal stem cell grafting helps to preserve cognitive function.

A Lethal Disease Model for Hantavirus Pulmonary Syndrome in Immunosuppressed Syrian Hamsters Infected with Sin Nombre Virus

PubMed Central

Brocato, Rebecca L.; Hammerbeck, Christopher D.; Bell, Todd M.; Wells, Jay B.; Queen, Laurie A.

2014-01-01

Sin Nombre virus (SNV) is a rodent-borne hantavirus that causes hantavirus pulmonary syndrome (HPS) predominantly in North America. SNV infection of immunocompetent hamsters results in an asymptomatic infection; the only lethal disease model for a pathogenic hantavirus is Andes virus (ANDV) infection of Syrian hamsters. Efforts to create a lethal SNV disease model in hamsters by repeatedly passaging virus through the hamster have demonstrated increased dissemination of the virus but no signs of disease. In this study, we demonstrate that immunosuppression of hamsters through the administration of a combination of dexamethasone and cyclophosphamide, followed by infection with SNV, results in a vascular leak syndrome that accurately mimics both HPS disease in humans and ANDV infection of hamsters. Immunosuppressed hamsters infected with SNV have a mean number of days to death of 13 and display clinical signs associated with HPS, including pulmonary edema. Viral antigen was widely detectable throughout the pulmonary endothelium. Histologic analysis of lung sections showed marked inflammation and edema within the alveolar septa of SNV-infected hamsters, results which are similar to what is exhibited by hamsters infected with ANDV. Importantly, SNV-specific neutralizing polyclonal antibody administered 5 days after SNV infection conferred significant protection against disease. This experiment not only demonstrated that the disease was caused by SNV, it also demonstrated the utility of this animal model for testing candidate medical countermeasures. This is the first report of lethal disease caused by SNV in an adult small-animal model. PMID:24198421

A lethal disease model for hantavirus pulmonary syndrome in immunosuppressed Syrian hamsters infected with Sin Nombre virus.

PubMed

Brocato, Rebecca L; Hammerbeck, Christopher D; Bell, Todd M; Wells, Jay B; Queen, Laurie A; Hooper, Jay W

2014-01-01

Sin Nombre virus (SNV) is a rodent-borne hantavirus that causes hantavirus pulmonary syndrome (HPS) predominantly in North America. SNV infection of immunocompetent hamsters results in an asymptomatic infection; the only lethal disease model for a pathogenic hantavirus is Andes virus (ANDV) infection of Syrian hamsters. Efforts to create a lethal SNV disease model in hamsters by repeatedly passaging virus through the hamster have demonstrated increased dissemination of the virus but no signs of disease. In this study, we demonstrate that immunosuppression of hamsters through the administration of a combination of dexamethasone and cyclophosphamide, followed by infection with SNV, results in a vascular leak syndrome that accurately mimics both HPS disease in humans and ANDV infection of hamsters. Immunosuppressed hamsters infected with SNV have a mean number of days to death of 13 and display clinical signs associated with HPS, including pulmonary edema. Viral antigen was widely detectable throughout the pulmonary endothelium. Histologic analysis of lung sections showed marked inflammation and edema within the alveolar septa of SNV-infected hamsters, results which are similar to what is exhibited by hamsters infected with ANDV. Importantly, SNV-specific neutralizing polyclonal antibody administered 5 days after SNV infection conferred significant protection against disease. This experiment not only demonstrated that the disease was caused by SNV, it also demonstrated the utility of this animal model for testing candidate medical countermeasures. This is the first report of lethal disease caused by SNV in an adult small-animal model.

Cell killing and chromatid damage in primary human bronchial epithelial cells irradiated with accelerated 56Fe ions

NASA Technical Reports Server (NTRS)

Suzuki, M.; Piao, C.; Hall, E. J.; Hei, T. K.

2001-01-01

We examined cell killing and chromatid damage in primary human bronchial epithelial cells irradiated with high-energy 56Fe ions. Cells were irradiated with graded doses of 56Fe ions (1 GeV/nucleon) accelerated with the Alternating Gradient Synchrotron at Brookhaven National Laboratory. The survival curves for cells plated 1 h after irradiation (immediate plating) showed little or no shoulder. However, the survival curves for cells plated 24 h after irradiation (delayed plating) had a small initial shoulder. The RBE for 56Fe ions compared to 137Cs gamma rays was 1.99 for immediate plating and 2.73 for delayed plating at the D10. The repair ratio (delayed plating/immediate plating) was 1.67 for 137Cs gamma rays and 1.22 for 56Fe ions. The dose-response curves for initially measured and residual chromatid fragments detected by the Calyculin A-mediated premature chromosome condensation technique showed a linear response. The results indicated that the induction frequency for initially measured fragments was the same for 137Cs gamma rays and 56Fe ions. On the other hand, approximately 85% of the fragments induced by 137Cs gamma rays had rejoined after 24 h of postirradiation incubation; the corresponding amount for 56Fe ions was 37%. Furthermore, the frequency of chromatid exchanges induced by gamma rays measured 24 h after irradiation was higher than that induced by 56Fe ions. No difference in the amount of chromatid damage induced by the two types of radiations was detected when assayed 1 h after irradiation. The results suggest that high-energy 56Fe ions induce a higher frequency of complex, unrepairable damage at both the cellular and chromosomal levels than 137Cs gamma rays in the target cells for radiation-induced lung cancers.

Gene expression analysis and microdialysis suggest hypothalamic triiodothyronine (T3) gates daily torpor in Djungarian hamsters (Phodopus sungorus).

PubMed

Bank, Jonathan H H; Cubuk, Ceyda; Wilson, Dana; Rijntjes, Eddy; Kemmling, Julia; Markovsky, Hanna; Barrett, Perry; Herwig, Annika

2017-07-01

Thyroid hormones play an important role in regulating seasonal adaptations of mammals. Several studies suggested that reduced availability of 3,3',5-triiodothyronine (T3) in the hypothalamus is required for the physiological adaptation to winter in Djungarian hamsters. We have previously shown that T3 is involved in the regulation of daily torpor, but it remains unclear, whether T3 affects torpor by central or peripheral mechanisms. To determine the effect of T3 concentrations within the hypothalamus in regulating daily torpor, we tested the hypothesis that low hypothalamic T3 metabolism would favour torpor and high T3 concentrations would not. In experiment 1 gene expression in torpid hamsters was assessed for transporters carrying thyroid hormones between cerebrospinal fluid and hypothalamic cells and for deiodinases enzymes, activating or inactivating T3 within hypothalamic cells. Gene expression analysis suggests reduced T3 in hypothalamic cells during torpor. In experiment 2, hypothalamic T3 concentrations were altered via microdialysis and torpor behaviour was continuously monitored by implanted body temperature transmitters. Increased T3 concentrations in the hypothalamus reduced expression of torpor as well as torpor bout duration and depth. Subsequent analysis of gene expression in the ependymal layer of the third ventricle showed clear up-regulation of T3 inactivating deiodinase 3 but no changes in several other genes related to photoperiodic adaptations in hamsters. Finally, serum analysis revealed that increased total T3 serum concentrations were not necessary to inhibit torpor expression. Taken together, our results are consistent with the hypothesis that T3 availability within the hypothalamus significantly contributes to the regulation of daily torpor via a central pathway.

Chinese hamster ovary K1 host cell enables stable cell line development for antibody molecules which are difficult to express in DUXB11-derived dihydrofolate reductase deficient host cell.

PubMed

Hu, Zhilan; Guo, Donglin; Yip, Shirley S M; Zhan, Dejin; Misaghi, Shahram; Joly, John C; Snedecor, Bradley R; Shen, Amy Y

2013-01-01

Therapeutic monoclonal antibodies (mAb) are often produced in Chinese hamster ovary (CHO) cells. Three commonly used CHO host cells for generating stable cell lines to produce therapeutic proteins are dihydrofolate reductase (DHFR) positive CHOK1, DHFR-deficient DG44, and DUXB11-based DHFR deficient CHO. Current Genentech commercial full-length antibody products have all been produced in the DUXB11-derived DHFR-deficient CHO host. However, it has been challenging to develop stable cell lines producing an appreciable amount of antibody proteins in the DUXB11-derived DHFR-deficient CHO host for some antibody molecules and the CHOK1 host has been explored as an alternative approach. In this work, stable cell lines were developed for three antibody molecules in both DUXB11-based and CHOK1 hosts. Results have shown that the best CHOK1 clones produce about 1 g/l for an antibody mAb1 and about 4 g/l for an antibody mAb2 in 14-day fed batch cultures in shake flasks. In contrast, the DUXB11-based host produced ∼0.1 g/l for both antibodies in the same 14-day fed batch shake flask production experiments. For an antibody mAb3, both CHOK1 and DUXB11 host cells can generate stable cell lines with the best clone in each host producing ∼2.5 g/l. Additionally, studies have shown that the CHOK1 host cell has a larger endoplasmic reticulum and higher mitochondrial mass. © 2013 American Institute of Chemical Engineers.

Altered Gene Expression Patterns During the Initiation and Promotion Stages of Neonatally Diethylstilbestrol-Induced Hyperplasia/Dysplasia/Neoplasia in the Hamster Uterus

PubMed Central

Hendry, William J.; Hariri, Hussam Y.; Alwis, Imala D.; Gunewardena, Sumedha S.; Hendry, Isabel R.

2014-01-01

Neonatal treatment of hamsters with diethylstilbestrol (DES) induces uterine hyperplasia/dysplasia/neoplasia (endometrial adenocarcinoma) in adult animals. We subsequently determined that the neonatal DES exposure event directly and permanently disrupts the developing hamster uterus (initiation stage) so that it responds abnormally when it is stimulated with estrogen in adulthood (promotion stage). To identify candidate molecular elements involved in progression of the disruption/neoplastic process, we performed: 1) immunoblot analyses and 2) microarray profiling (Affymetrix Gene Chip System) on sets of uterine protein and RNA extracts, respectively, and 3) immunohistochemical analysis on uterine sections; all from both initiation stage and promotion stage groups of animals. Here we report that: 1) progression of the neonatal DES-induced hyperplasia/dysplasia/neoplasia phenomenon in the hamster uterus involves a wide spectrum of specific gene expression alterations and 2) the gene products involved and their manner of altered expression differ dramatically during the initiation vs. promotion stages of the phenomenon. Particularly interesting changes included members in the functional categories of nuclear receptors (progesterone receptor), cell-cell interactions (E-cadherin, connexins), cytokine action (IRF-1, Stat5A), growth factor action (IRS-1), extracellular matrix component (tenascin-C), transcription factors (Nrf2, Sp1), and multi-functional nuclear protein (SAFB1). PMID:25242112

Topical photosan-mediated photodynamic therapy for DMBA-induced hamster buccal pouch early cancer lesions: an in vivo study

NASA Astrophysics Data System (ADS)

Hsu, Yih-Chih; Chang, Walter Hong-Shong; Chang, Junn-Liang; Liu, Kuang-Ting; Chiang, Chun-Pin; Liu, Chung-Ji; Chen, Chih-Ping

2011-03-01

Oral cancer has becomes the most prominent cancer disease in recent years in Taiwan. The reason is the betel nut chewing habit combing with smoking and alcohol-drinking lifestyle of people results in oral cancer becomes the fastest growth incident cancer amongst other major cancer diseases. In previous studies showed that photosan, haematoporphyrin derivative (HPD), has demonstrated effective PDT results on human head and neck disease studies. To avoid the systemic phototoxic effect of photosan, this study was designed to use a topical photosan-mediated PDT for treatment of DMBA-induced hamster buccal pouch cancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 10 to 12 weeks. Cancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical photosan-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when photosan reached its peak level in the lesional epithelial cells after topical application of photosan gel. We found that photosan reached its peak level in cancerous lesions about 13.5 min after topical application of photosan gel. The cancerous lesions in hamsters were then treated with topical photosan-mediated PDT (fluence rate: 600 mW/cm2; light exposure dose 200 J/cm2) using the portable Lumacare 635 nm fiber-guided light device. Visual examination demonstrated that topical photosan-mediated PDT was an applicable treatment modality for DMBA-induced hamster buccal pouch cancerous lesions.

Temperature dependence of damage coefficient in electron irradiated solar cells

NASA Technical Reports Server (NTRS)

Faith, T. J.

1973-01-01

Measurements of light-generated current vs cell temperature on electron-irradiated n/p silicon solar cells show the temperature coefficient of this current to increase with increasing fluence for both 10-ohm and 20-ohm cells. A relationship between minority-carrier diffusion length and light-generated current was derived by combining measurements of these two parameters: vs fluence at room temperature, and vs cell temperature in cells irradiated to a fluence of 1 x 10 to the 15th power e/sq cm. This relationship was used, together with the light-generated current data, to calculate the temperature dependence of the diffusion-length damage coefficient. The results show a strong decrease in the damage coefficient with increasing temperature in the range experienced by solar panels in synchronous earth orbit.

The Effect of Laser Irradiation on Adipose Derived Stem Cell Proliferation and Differentiation

NASA Astrophysics Data System (ADS)

Abrahamse, H.; de Villiers, J.; Mvula, B.

2009-06-01

There are two fundamental types of stem cells: Embryonic Stem cells and Adult Stem cells. Adult Stem cells have a more restricted potential and can usually differentiate into a few different cell types. In the body these cells facilitate the replacement or repair of damaged or diseased cells in organs. Low intensity laser irradiation was shown to increase stem cell migration and stimulate proliferation and it is thought that treatment of these cells with laser irradiation may increase the stem cell harvest and have a positive effect on the viability and proliferation. Our research is aimed at determining the effect of laser irradiation on differentiation of Adipose Derived Stem Cells (ADSCs) into different cell types using a diode laser with a wavelength of 636 nm and at 5 J/cm2. Confirmation of stem cell characteristics and well as subsequent differentiation were assessed using Western blot analysis and cellular morphology supported by fluorescent live cell imaging. Functionality of subsequent differentiated cells was confirmed by measuring adenosine triphosphate (ATP) production and cell viability.

Leptin mediates seasonal variation in some but not all symptoms of sickness in Siberian hamsters

PubMed Central

Carlton, Elizabeth D.; Demas, Gregory E.

2014-01-01

Many seasonally breeding species, including Siberian hamsters (Phodopus sungorus), exhibit seasonal variation in sickness responses. One hypothesis regarding the mechanism of this variation is that sickness intensity tracks an animal's energetic state, such that sickness is attenuated in the season that an animal has the lowest fat stores. Energetic state may be signaled via leptin, an adipose hormone that provides a signal of fat stores. Siberian hamsters respond to extended housing in short, winter-like days by reducing fat stores and leptin levels, relative to those housed in long, summer-like days. Sickness responses are also attenuated in short-day hamsters as compared to long-day hamsters. We hypothesized that leptin provides a physiological signal by which seasonally breeding animals modulate sickness responses, such that animals with higher leptin levels show increased sickness intensity. To test this, we provided short-day hamsters with a long-day-like leptin signal and assessed their responses to lipopolysaccharide (LPS), a sickness-inducing antigen. We compared these responses to short-day vehicle-, long-day vehicle-, and long-day leptin-treated hamsters. Unexpectedly, LPS induced a hypothermic response (rather than fever) in all groups. Short-day vehicle-treated hamsters exhibited the greatest LPS-induced hypothermia, and leptin treatment attenuated this response, making hypothermia more long-day-like. Contrary to our hypothesis, short-day leptin-treated hamsters showed the least pronounced LPS-induced anorexia among all groups. These results suggest that leptin may mediate some but not all aspects of seasonal sickness variation in this species. Future studies should be targeted at determining roles of other energetic hormones in regulating seasonal sickness response variation. PMID:25461974

[Screening of virulence gene in golden hamster cheek pouch mucosa carcinomatous change induced by 9,10-dimethylene-1,2-benzanthracene].

PubMed

Zhang, Guo-dong; Yang, Kai; Mei, Jie

2010-05-01

To examine and analyze the global gene expression at the different stages of golden hamster cheek pouch mucosa carcinomatous change induced by 9,10-dimethylene-1,2 benzanthracene (DMBA). The model of golden hamster cheek pouch squamous cell carcinoma was induced by DMBA. The RNA of normal mucosa, precancerous lesions and squamous cell carcinoma of fresh tissue of golden hamsters was extracted and purified and the cRNA labeled by fluorescent Cy3 synthesized, which respectively hybridized with the agilent rat cDNA microarray containing 41 000 genes-expressed sequence tags, scanning with Agilent G2565AA fluorescence scanner. The Ratio>or=2 and Ratiocell carcinoma, of which 2896 was up-regulated and 2359 down-regulated. There were 22 genes that showed continues abnormal expression through the three different stages of carcinomatous change, including 3 up-regulated, 19 down-regulated. The RT-PCR results of Eaf-2 and Ecg-2 were consistent with the gene chip. The development of oral mucosal squamous cell carcinoma involved a number of abnormal genes. The genes showing continues abnormal expression at different stages of carcinomatous change may be the important pathogenetic ones.

Theileria parva: effects of irradiation on a culture of parasitized bovine lymphoid cells. [Gamma radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Irvin, A.D.; Brown, C.G.D.; Stagg, D.A.

1975-01-01

Aliquots of a culture of Theileria parva-infected bovine lymphoid cells were irradiated at 0, 300, 600, 900, and 1200 rads. The short-term effects of irradiation were evaluated on examination of Giemsa-stained smears and on autoradiography of cells labeled with (/sup 3/H)thymidine. Irradiation inhibited cell division but parasite division did not appear to be inhibited and macroschizont nuclear particles increased in number, frequently to several hundred per schizont. There was no evidence of an increased percentage switch from macro- to microschizont. Apparently viable cells were still present in all cultures 4 days after irradiation.

Induction of micronuclei and apoptosis in natural killer cells compared to T lymphocytes after gamma-irradiation.

PubMed

Louagie, H; Philippé, J; Vral, A; Cornelissen, M; Thierens, H; De Ridder, L

1998-02-01

To investigate the chromosomal damage caused by gamma-irradiation in T lymphocytes and natural killer (NK) cells and compare this with apoptosis induction in both lymphocyte subsets. Apoptosis induction by gamma-irradiation in T lymphocytes and NK cells was quantified using the annexin V flow cytometric assay. The cytokinesis-block micronucleus (MN) assay was used to evaluate the induced cytogenetic damage. For the MN assays on NK cells, gamma-irradiated peripheral blood mononuclear cells were cultured and stimulated with interleukin 15 (IL-15). Afterwards the NK cells (characterized by the CD3-/CD56+ phenotype) were separated with the FACSort flow cytometer and the number of MN in the sorted binuclear cells was scored. Doses of 1 and 2 Gy gamma-irradiation were applied. Higher numbers of MN in NK cells were found compared with the MN yield in T lymphocytes. In contrast, NK cells were less than T lymphocytes prone to apoptosis after gamma-irradiation. The results support the view that cytogenetic damage and apoptosis after gamma-irradiation are not necessarily correlated.

HPRT mutations in V79 Chinese hamster cells induced by accelerated Ni, Au and Pb ions.

PubMed

Stoll, U; Barth, B; Scheerer, N; Schneider, E; Kiefer, J

1996-07-01

Mutation induction by accelerated heavy ions to 6-TG resistance (HPRT system) in V79 Chinese hamster cells was investigated with Ni (6-630 Me V/u), Au (2.2, 8.7 Me V/u) and Pb ions (11.6-980 Me V/u) corresponding to a LET range between 180 and 12895 ke V/microns. Most experiments could only be performed once due to technical limitations using accelerator beam times. Survival curves were exponential, mutation induction curves linear with fluence. From their slopes inactivation- and mutation-induction cross-sections were derived. If they are plotted versus LET, single, ion-specific curves are obtained. It is shown that other parameters like ion energy and effective charge play an important role. In the case of Au and Pb ions the cross-sections follow a common line, since these ions have nearly the same atomic weight, so that they should have similar spatial ionization patterns in matter at the same energies. Calculated RBEs were higher for mutation induction than for killing for all LETs.

Spatially-Selective Membrane Permeabilization Induced by Cell-Solution Electrode Atmospheric Pressure Plasma Irradiation

NASA Astrophysics Data System (ADS)

Sasaki, Shota; Hokari, Yutaro; Kanzaki, Makoto; Kaneko, Toshiro

2015-09-01

Gene transfection, which is the process of deliberately introducing nucleic acids into cells, is expected to play an important role in medical treatment because the process is necessary for gene therapy and creation of induced pluripotent stem (iPS) cells. However, the conventional transfection methods have some problems, so we focus attention on promising transfection methods by atmospheric pressure plasma (APP). We have previously reported that the cell membrane permeability, which is closely related with gene transfection, is improved using a cell-solution electrode for generating He-APP. He-APP is irradiated to the solution containing the adherent cells and delivery materials such as fluorescent dyes (YOYO-1) and plasmid DNA (GFP). In case of YOYO-1 delivery, more than 80% of cells can be transferred only in the plasma-irradiated area and the spatially-selective membrane permeabilization is realized by the plasma irradiation. In addition, it is confirmed that plasmid DNA is transfected and the GFP genes are expressed using same APP irradiation system with no obvious cellular damage.

Vasopressin differentially modulates aggression and anxiety in adolescent hamsters administered anabolic steroids.

PubMed

Morrison, Thomas R; Ricci, Lesley A; Melloni, Richard H

2016-11-01

Adolescent Syrian hamsters (Mesocricetus auratus) treated with anabolic/androgenic steroids display increased offensive aggression and decreased anxiety correlated with an increase in vasopressin afferent development, synthesis, and neural signaling within the anterior hypothalamus. Upon withdrawal from anabolic/androgenic steroids, this neurobehavioral relationship shifts as hamsters display decreased offensive aggression and increased anxiety correlated with a decrease in anterior hypothalamic vasopressin. This study investigated the hypothesis that alterations in anterior hypothalamic vasopressin neural signaling modulate behavioral shifting between adolescent anabolic/androgenic steroid-induced offensive aggression and anxiety. To test this, adolescent male hamsters were administered anabolic/androgenic steroids and tested for offensive aggression or anxiety following direct pharmacological manipulation of vasopressin V1A receptor signaling within the anterior hypothalamus. Blockade of anterior hypothalamic vasopressin V1A receptor signaling suppressed offensive aggression and enhanced general and social anxiety in hamsters administered anabolic/androgenic steroids during adolescence, effectively reversing the pattern of behavioral response pattern normally observed during the adolescent exposure period. Conversely, activation of anterior hypothalamic vasopressin V1A receptor signaling enhanced offensive aggression in hamsters exposed to anabolic/androgenic steroids during adolescence. Together, these findings suggest that the state of vasopressin neural development and signaling in the anterior hypothalamus plays an important role in behavioral shifting between aggression and anxiety following adolescent exposure to anabolic/androgenic steroids. Copyright © 2016 Elsevier Inc. All rights reserved.

Vasopressin Differentially Modulates Aggression and Anxiety in Adolescent Hamsters Administered Anabolic Steroids

PubMed Central

Morrison, Thomas R.; Ricci, Lesley A.; Melloni, Richard H.

2016-01-01

Adolescent Syrian hamsters (Mesocricetus auratus) treated with anabolic/androgenic steroids display increased offensive aggression and decreased anxiety correlated with an increase in vasopressin afferent development, synthesis, and neural signaling within the anterior hypothalamus. Upon withdrawal from anabolic/androgenic steroids, this neurobehavioral relationship shifts as hamsters display decreased offensive aggression and increased anxiety correlated with a decrease in anterior hypothalamic vasopressin. This study investigated the hypothesis that alterations in anterior hypothalamic vasopressin neural signaling modulate behavioral shifting between adolescent anabolic/androgenic steroid-induced offensive aggression and anxiety. To test this, adolescent male hamsters were administered anabolic/androgenic steroids and tested for offensive aggression or anxiety following direct pharmacological manipulation of vasopressin V1A receptor signaling within the anterior hypothalamus. Blockade of anterior hypothalamic vasopressin V1A receptor signaling suppressed offensive aggression and enhanced general and social anxiety in hamsters administered anabolic/androgenic steroids during adolescence, effectively reversing the pattern of behavioral response pattern normally observed during the adolescent exposure period. Conversely, activation of anterior hypothalamic vasopressin V1A receptor signaling enhanced offensive aggression in hamsters exposed to anabolic/androgenic steroids during adolescence. Together, these findings suggest that the state of vasopressin neural development and signaling in the anterior hypothalamus plays an important role in behavioral shifting between aggression and anxiety following adolescent exposure to anabolic/androgenic steroids. PMID:27149949

Estimation of the radiation-induced DNA double-strand breaks number by considering cell cycle and absorbed dose per cell nucleus

PubMed Central

Mori, Ryosuke; Matsuya, Yusuke; Yoshii, Yuji; Date, Hiroyuki

2018-01-01

Abstract DNA double-strand breaks (DSBs) are thought to be the main cause of cell death after irradiation. In this study, we estimated the probability distribution of the number of DSBs per cell nucleus by considering the DNA amount in a cell nucleus (which depends on the cell cycle) and the statistical variation in the energy imparted to the cell nucleus by X-ray irradiation. The probability estimation of DSB induction was made following these procedures: (i) making use of the Chinese Hamster Ovary (CHO)-K1 cell line as the target example, the amounts of DNA per nucleus in the logarithmic and the plateau phases of the growth curve were measured by flow cytometry with propidium iodide (PI) dyeing; (ii) the probability distribution of the DSB number per cell nucleus for each phase after irradiation with 1.0 Gy of 200 kVp X-rays was measured by means of γ-H2AX immunofluorescent staining; (iii) the distribution of the cell-specific energy deposition via secondary electrons produced by the incident X-rays was calculated by WLTrack (in-house Monte Carlo code); (iv) according to a mathematical model for estimating the DSB number per nucleus, we deduced the induction probability density of DSBs based on the measured DNA amount (depending on the cell cycle) and the calculated dose per nucleus. The model exhibited DSB induction probabilities in good agreement with the experimental results for the two phases, suggesting that the DNA amount (depending on the cell cycle) and the statistical variation in the local energy deposition are essential for estimating the DSB induction probability after X-ray exposure. PMID:29800455

Estimation of the radiation-induced DNA double-strand breaks number by considering cell cycle and absorbed dose per cell nucleus.

PubMed

Mori, Ryosuke; Matsuya, Yusuke; Yoshii, Yuji; Date, Hiroyuki

2018-05-01

DNA double-strand breaks (DSBs) are thought to be the main cause of cell death after irradiation. In this study, we estimated the probability distribution of the number of DSBs per cell nucleus by considering the DNA amount in a cell nucleus (which depends on the cell cycle) and the statistical variation in the energy imparted to the cell nucleus by X-ray irradiation. The probability estimation of DSB induction was made following these procedures: (i) making use of the Chinese Hamster Ovary (CHO)-K1 cell line as the target example, the amounts of DNA per nucleus in the logarithmic and the plateau phases of the growth curve were measured by flow cytometry with propidium iodide (PI) dyeing; (ii) the probability distribution of the DSB number per cell nucleus for each phase after irradiation with 1.0 Gy of 200 kVp X-rays was measured by means of γ-H2AX immunofluorescent staining; (iii) the distribution of the cell-specific energy deposition via secondary electrons produced by the incident X-rays was calculated by WLTrack (in-house Monte Carlo code); (iv) according to a mathematical model for estimating the DSB number per nucleus, we deduced the induction probability density of DSBs based on the measured DNA amount (depending on the cell cycle) and the calculated dose per nucleus. The model exhibited DSB induction probabilities in good agreement with the experimental results for the two phases, suggesting that the DNA amount (depending on the cell cycle) and the statistical variation in the local energy deposition are essential for estimating the DSB induction probability after X-ray exposure.

Decreasing temperature shifts hippocampal function from memory formation to modulation of hibernation bout duration in Syrian hamsters.

PubMed

Arant, Ryan J; Goo, Marisa S; Gill, Phoebe D; Nguyen, Yen; Watson, Katherine D; Hamilton, Jock S; Horowitz, John M; Horwitz, Barbara A

2011-08-01

Previous studies in hibernating species have characterized two forms of neural plasticity in the hippocampus, long-term potentiation (LTP) and its reversal, depotentiation, but not de novo long-term depression (LTD), which is also associated with memory formation. Studies have also shown that histamine injected into the hippocampus prolonged hibernation bout duration. However, spillover into the ventricles may have affected brain stem regions, not the hippocampus. Here, we tested the hypothesis that decreased brain temperature shifts the major function of the hippocampus in the Syrian hamster (Mesocricetus auratus) from one of memory formation (via LTP, depotentiation, and de novo LTD) to increasing hibernation bout duration. We found reduced evoked responses in hippocampal CA1 pyramidal neurons following low-frequency stimulation in young (<30 days old) and adult (>60 days old) hamsters, indicating that de novo LTD was generated in hippocampal slices from both pups and adults at temperatures >20°C. However, at temperatures below 20°C, synchronization of neural assemblies (a requirement for LTD generation) was markedly degraded, implying that de novo LTD cannot be generated in hibernating hamsters. Nonetheless, even at temperatures below 16°C, pyramidal neurons could still generate action potentials that may traverse a neural pathway, suppressing the ascending arousal system (ARS). In addition, histamine increased the excitability of these pyramidal cells. Taken together, these findings are consistent with the hypothesis that hippocampal circuits remain operational at low brain temperatures in Syrian hamsters and suppress the ARS to prolong bout duration, even though memory formation is muted at these low temperatures.

Chronic inhalation exposure of hamsters to nickel-enriched fly ash

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wehner, A.P.; Dagle, G.E.; Milliman, E.M.

1981-10-01

Hamsters were chronically exposed to approx.70 ..mu..g/liter respirable nickel-enriched fly ash (NEFA) aerosol, approx.17 ..mu..g/liter NEFA, or approx.70 ..mu..g/liter fly ash (FA) for up to 20 months. A control group received sham exposures. The NEFA particles of respirable size contained approximately 6% nickel, compared to about 0.3% for FA. Five hamsters/group were sacrificed after 4, 8, 12, or 16 months of exposure. An additional five hamsters/group were withdrawn from exposure at the same intervals for lifelong observations. Exposures to NEFA had no significant effect on body weight and life span of the animals although heavy deposits of NEFA in themore » lungs were demonstrated. However, lung weights of the high NEFA- and of the FA-exposed animals were significantly higher than those of the low-NEFA group and the controls, and mean lung volumes were significantly larger for the high-NEFA grop and the FA group than for the low-NEFA group and the controls. Dust was deposited (anthracosis) in the lungs of all exposed hamsters. Incidence and severity of interstitial reaction and bronchiolization were significantly higher in the dust-exposed groups than in the sham-exposed controls. The severity of anthracosis, interstitial reaction, and bronchiolization was significantly lower in the low-NEFA group than in the high-NEFA and FA groups. While two malignant primary thorax tumors were found in two hamsters of the high-NEFA group, no statistically significant carcinogenesis was observed. Of the exposure-related changes, only anthracosis decreased after withdrawal from exposure. Pulmonary nickel burdens after 20 months of exposure suggest that the pulmonary clearance rate was slower in the high-NEFA group than in the low-NEFA group.« less

Sunitinib Improves Some Clinical Aspects and Reverts DMBA-Induced Hyperplasic Lesions in Hamster Buccal Pouch

PubMed Central

de Souza, Fernanda Lopes; Oliveira, Mariana; Nunes, Marianne Brochado; Serafim, Lucas Horstmann; Azambuja, Alan Arrieira; Braga, Luisa Maria G. de M.; Saur, Lisiani; de Souza, Maria Antonieta Lopes; Xavier, Léder Leal

2014-01-01

Oral squamous cell carcinoma (OSCC) is a public health problem. The hamster buccal pouch model is ideal for analyzing the development of OSCC. This research analysed the effects of sunitinib (tyrosine kinase inhibitor) in precancerous lesions induced by 7,12-dimethylbenz(a)anthracene (DMBA) in this model. Thirty-four male hamsters, divided into six groups: control—C (n = 7), acetone—A (n = 12), carbamide peroxide—CP (n = 5 ), acetone and CP—A+CP (n = 8), 1% DMBA in acetone and CP—DA+CP (n = 6), and 1% DMBA in acetone and CP and 4-week treatment with sunitinib—DA+CP+S (n = 7). The aspects evaluated were anatomopathological features (peribuccal area, paws, nose, and fur), histological sections of the hamster buccal pouches (qualitatively analyzed), epithelium thickness, and the rete ridge density (estimated). Sunitinib was unable to attenuate the decrease in weight gain induced by DMBA; no increase in volume was detected in the pouch and/or ulceration, observed in 43% of the animals in the DA+CP group. DA+CP groups presented a significant increase in rete ridge density compared to the control groups (P < 0.01) which was reverted by sunitinib in the DA+CP+S group. Sunitinib seems to have important benefits in early stage carcinogenesis and may be useful in chemoprevention. PMID:24693453

Chromatin remodeling modulates radiosensitivity of the daughter cells derived from cell population exposed to low- and high-LET irradiation

PubMed Central

Chen, Xiaoyan; Zhu, Lin; Zhang, Hang; Wang, Chen; Shao, Chunlin

2017-01-01

Radiation effects are dependent of linear energy transfer (LET), but it is still obscure whether the daughter cells (DCs) derived from irradiated population are radioresistance and much less the underlying mechanism. With the measurements of survival, proliferation and γH2AX foci, this study shows that the DCs from γ-ray irradiated cells (DCs-γ) became more radioresistant than its parent control without irradiation, but the radiosensitivity of DCs from α-particle irradiated cells (DCs-α) was not altered. After irradiation with equivalent doses of γ-rays and α-particles, the foci number of histone H3 lysine 9 dimethylation (H3K9me3) and the activity of histone deacetylase (HDAC) in DCs-γ was extensively higher than these in DCs-α and its parent control, indicating that a higher level of heterochromatin was formed in DCs-γ but not in DCs-α. Treatment of cells with SAHA (an inhibitor of HDAC) decreased the level of heterochromatin domains by inhibiting the expressions of H3K9m3 and HP-1a proteins and triggering the expression of acetylated core histone H3 (Ac-H3). When cells were treated with SAHA, the radioresistance phenotype of DCs-γ was eliminated so that the radiosensitivities of DCs-γ, DCs-α and their parent cells approached to same levels. Our current results reveal that γ-rays but not α-particles could induce chromatin remodeling and heterochromatinization which results in the occurrence of radioresistance of DCs, indicating that the combination treatment of irradiation and HDAC inhibitor could serve as a potential cancer therapy strategy, especially for the fraction radiotherapy of low-LET irradiation. PMID:28881774

Omega 3 Fatty Acids Promote Macrophage Reverse Cholesterol Transport in Hamster Fed High Fat Diet

PubMed Central

Kasbi Chadli, Fatima; Nazih, Hassane; Krempf, Michel; Nguyen, Patrick; Ouguerram, Khadija

2013-01-01

The aim of this study was to investigate macrophage reverse cholesterol transport (RCT) in hamster, a CETP-expressing species, fed omega 3 fatty acids (ω3PUFA) supplemented high fat diet (HFD). Three groups of hamsters (n = 6/group) were studied for 20 weeks: 1) control diet: Control, 2) HFD group: HF and 3) HFD group supplemented with ω3PUFA (EPA and DHA): HFω3. In vivo macrophage-to-feces RCT was assessed after an intraperitoneal injection of 3H-cholesterol-labelled hamster primary macrophages. Compared to Control, HF presented significant (p<0.05) increase in body weight, plasma TG (p<0.01) and cholesterol (p<0.001) with an increase in VLDL TG and in VLDL and LDL cholesterol (p<0.001). Compared to HF, HFω3 presented significant decrease in body weight. HFω3 showed less plasma TG (p<0.001) and cholesterol (p<0.001) related to a decrease in VLDL TG and HDL cholesterol respectively and higher LCAT activity (p<0.05) compared to HF. HFω3 showed a higher fecal bile acid excretion (p<0.05) compared to Control and HF groups and higher fecal cholesterol excretion (p<0.05) compared to HF. This increase was related to higher gene expression of ABCG5, ABCA1 and SR-B1 in HFω3 compared to Control and HF groups (<0.05) and in ABCG1 and CYP7A1 compared to HF group (p<0.05). A higher plasma efflux capacity was also measured in HFω3 using 3H- cholesterol labeled Fu5AH cells. In conclusion, EPA and DHA supplementation improved macrophage to feces reverse cholesterol transport in hamster fed HFD. This change was related to the higher cholesterol and fecal bile acids excretion and to the activation of major genes involved in RCT. PMID:23613796

HTB140 melanoma cells under proton irradiation and/or alkylating agents

NASA Astrophysics Data System (ADS)

Korićanac, L.; Petrović, I.; Privitera, G.; Cuttone, G.; Ristić-Fira, A.

2007-09-01

Chemoresistance is a major problem in the treatment of malignant melanoma. The mainstay of treatment for melanoma is the DNA-alkylating agent dacarbazine (DTIC). Fotemustine (FM), a member of the chloroethylnitrosourea group of alkylating agents, has also demonstrated significant antitumor effects in malignant melanoma. However, the intrinsic and acquired resistance of melanoma limits the clinical application of these drugs. Melanomas are also extremely radioresistant. With the objective of enhancing growth inhibition of melanoma cells, combined treatments of FM or DTIC with proton irradiation have been investigated. These effects were studied on HTB140 melanoma cell viability and proliferation. Cells exposed to treatment with FM and protons have shown inhibition of cell growth and significant reduction of proliferation capacity compared to single irradiation or drug treatment. Treatment with DTIC and protons has shown improved growth inhibition compared to appropriate single drug treatment, while the effects of single proton irradiation have been the most pronounced.

Neurotensin is an antagonist of the human neurotensin NT2 receptor expressed in Chinese hamster ovary cells.

PubMed

Vita, N; Oury-Donat, F; Chalon, P; Guillemot, M; Kaghad, M; Bachy, A; Thurneyssen, O; Garcia, S; Poinot-Chazel, C; Casellas, P; Keane, P; Le Fur, G; Maffrand, J P; Soubrie, P; Caput, D; Ferrara, P

1998-11-06

The human levocabastine-sensitive neurotensin NT2 receptor was cloned from a cortex cDNA library and stably expressed in Chinese hamster ovary (CHO) cells in order to study its binding and signalling characteristics. The receptor binds neurotensin as well as several other ligands already described for neurotensin NT1 receptor. It also binds levocabastine, a histamine H1 receptor antagonist that is not recognised by neurotensin NT1 receptor. Neurotensin binding to recombinant neurotensin NT2 receptor expressed in CHO cells does not elicit a biological response as determined by second messenger measurements. Levocabastine, and the peptides neuromedin N and xenin were also ineffective on neurotensin NT2 receptor activation. Experiments with the neurotensin NT1 receptor antagonists SR48692 and SR142948A, resulted in the unanticipated discovery that both molecules are potent agonists on neurotensin NT2 receptor. Both compounds, following binding to neurotensin NT2 receptor, enhance inositol phosphates (IP) formation with a subsequent [Ca2+]i mobilisation; induce arachidonic acid release; and stimulate mitogen-activated protein kinase (MAPK) activity. Interestingly, these activities are antagonised by neurotensin and levocabastine in a concentration-dependent manner. These activities suggest that the human neurotensin NT2 receptor may be of physiological importance and that a natural agonist for the receptor may exist.

Efficacy of 2'-C-methylcytidine against yellow fever virus in cell culture and in a hamster model.

PubMed

Julander, Justin G; Jha, Ashok K; Choi, Jung-Ae; Jung, Kie-Hoon; Smee, Donald F; Morrey, John D; Chu, Chung K

2010-06-01

Yellow fever virus (YFV) continues to cause outbreaks of disease in endemic areas where vaccine is underutilized. Due to the effectiveness of the vaccine, antiviral development solely for the treatment of YFV is not feasible, but antivirals that are effective in the treatment of related viral diseases may be characterized for potential use against YFV as a secondary indication disease. 2'-C-methylcytidine (2'-C-MeC), a compound active against hepatitis C virus, was found to have activity against the 17D vaccine strain of YFV in cell culture (EC(90)=0.32 microg/ml, SI=141). This compound was effective when added as late as 16 h after virus challenge of Vero cells. When administered to YFV-infected hamsters 4 h prior to virus challenge at a dose as low as 80 mg/kg/d, 2'-C-MeC was effective in significantly improving survival and other disease parameters (weight change, serum ALT, and liver virus titers). Disease was improved when compound was administered beginning as late as 3 d post-virus infection. Broadly active antiviral compounds, such as 2'-C-MeC, represent potential for the development of compounds active against related viruses for the treatment of YFV. Copyright 2010 Elsevier B.V. All rights reserved.

Analysis of mutant quantity and quality in human-hamster hybrid AL and AL-179 cells exposed to 137Cs-gamma or HZE-Fe ions

NASA Technical Reports Server (NTRS)

Waldren, C.; Vannais, D.; Drabek, R.; Gustafson, D.; Kraemer, S.; Lenarczyk, M.; Kronenberg, A.; Hei, T.; Ueno, A.; Chatterjee, A. (Principal Investigator)

1998-01-01

We measured the number of mutants and the kinds of mutations induced by 137Cs-gamma and by HZE-Fe (56Fe [600 MeV/amu, LET = 190 KeV/micrometer) in standard AL human hamster hybrid cells and in a new variant hybrid, AL-179. We found that HZE-Fe was more mutagenic than 137Cs-gamma per unit dose (about 1.6 fold), but was slightly less mutagenic per mean lethal dose, DO, at both the S1 and hprt- loci of AL cells. On the other hand, HZE-Fe induced about nine fold more complex S1- mutants than 137Cs-gamma rays, 28% vs 3%. 137Cs-gamma rays induced about twice as many S1- mutants and hprt-mutants in AL-179 as in AL cells, and about nine times more of the former were complex, and potentially unstable kinds of mutations.

Winning agonistic encounters increases testosterone and androgen receptor expression in Syrian Hamsters

PubMed Central

Clinard, Catherine T.; Barnes, Abigail K.; Adler, Samuel G.; Cooper, Matthew A.

2016-01-01

Winning aggressive disputes is one of several experiences that can alter responses to future stressful events. We have previously tested dominant and subordinate male Syrian hamsters in a conditioned defeat model and found that dominant individuals show less change in behavior following social defeat stress compared to subordinates and controls, indicating a reduced conditioned defeat response. Resistance to the effects of social defeat in dominants is experience-dependent and requires the maintenance of dominance relationships for 14 days. For this study we investigated whether winning aggressive interactions increases plasma testosterone and whether repeatedly winning increases androgen receptor expression. First, male hamsters were paired in daily 10-min aggressive encounters and blood samples were collected immediately before and 15-min and 30-min after the formation of dominance relationships. Dominants showed an increase in plasma testosterone at 15-min post-interaction compared to their pre-interaction baseline, whereas subordinates and controls showed no change in plasma testosterone. Secondly, we investigated whether 14 days of dominant social status increased androgen or estrogen alpha-receptor immunoreactivity in brain regions that regulate the conditioned defeat response. Dominants showed more androgen, but not estrogen alpha, receptor immuno-positive cells in the dorsal medial amygdala (dMeA) and ventral lateral septum (vLS) compared to subordinates and controls. Finally, we showed that one day of dominant social status was insufficient to increase androgen receptor immunoreactivity compared to subordinates. These results suggest that elevated testosterone signaling at androgen receptors in the dMeA and vLS might contribute to the reduced conditioned defeat response exhibited by dominant hamsters. PMID:27619945

Comparison of human lung cancer cell radiosensitivity after irradiations with therapeutic protons and carbon ions.

PubMed

Keta, Otilija D; Todorović, Danijela V; Bulat, Tanja M; Cirrone, Pablo Ga; Romano, Francesco; Cuttone, Giacomo; Petrović, Ivan M; Ristić Fira, Aleksandra M

2017-05-01

The aim of this study was to investigate effects of irradiations with the therapeutic proton and carbon ion beams in two non-small cell lung cancers, CRL5876 adenocarcinoma and HTB177 large cell lung carcinoma. The DNA damage response dynamics, cell cycle regulation, and cell death pathway activation were followed. Viability of both cell lines was lower after carbon ions compared to the therapeutic proton irradiations. HTB177 cells showed higher recovery than CRL5876 cells seven days following the treatments, but the survival rates of both cell lines were lower after exposure to carbon ions with respect to therapeutic protons. When analyzing cell cycle distribution of both CRL5876 and HTB177 cells, it was noticed that therapeutic protons predominantly induced G1 arrest, while the cells after carbon ions were arrested in G2/M phase. The results illustrated that differences in the levels of phosphorylated H2AX, a double-strand break marker, exist after therapeutic proton and carbon ion irradiations. We also observed dose- and time-dependent increase in the p53 and p21 levels after applied irradiations. Carbon ions caused larger increase in the quantity of p53 and p21 compared to therapeutic protons. These results suggested that various repair mechanisms were induced in the treated cells. Considering the fact that we have not observed any distinct change in the Bax/Bcl-2 ratio following irradiations, it seemed that different types of cell death were involved in the response to the two types of irradiations that were applied.

Comparison of human lung cancer cell radiosensitivity after irradiations with therapeutic protons and carbon ions

PubMed Central

Keta, Otilija D; Todorović, Danijela V; Bulat, Tanja M; Cirrone, Pablo GA; Romano, Francesco; Cuttone, Giacomo; Petrović, Ivan M

2016-01-01

The aim of this study was to investigate effects of irradiations with the therapeutic proton and carbon ion beams in two non-small cell lung cancers, CRL5876 adenocarcinoma and HTB177 large cell lung carcinoma. The DNA damage response dynamics, cell cycle regulation, and cell death pathway activation were followed. Viability of both cell lines was lower after carbon ions compared to the therapeutic proton irradiations. HTB177 cells showed higher recovery than CRL5876 cells seven days following the treatments, but the survival rates of both cell lines were lower after exposure to carbon ions with respect to therapeutic protons. When analyzing cell cycle distribution of both CRL5876 and HTB177 cells, it was noticed that therapeutic protons predominantly induced G1 arrest, while the cells after carbon ions were arrested in G2/M phase. The results illustrated that differences in the levels of phosphorylated H2AX, a double-strand break marker, exist after therapeutic proton and carbon ion irradiations. We also observed dose- and time-dependent increase in the p53 and p21 levels after applied irradiations. Carbon ions caused larger increase in the quantity of p53 and p21 compared to therapeutic protons. These results suggested that various repair mechanisms were induced in the treated cells. Considering the fact that we have not observed any distinct change in the Bax/Bcl-2 ratio following irradiations, it seemed that different types of cell death were involved in the response to the two types of irradiations that were applied. PMID:27633574

[Decorative forms of hamsters Phodopus (Mammalia, Cricetinae): an analysis of genetic lines distribution and peculiarities of hair changes].

PubMed

Feoktistova, N Iu; Chernova, O F; Meshcherskiĭ, I G

2012-01-01

Three species of dwarf hamsters (genus Phodopus, family Cricetidae) inhabit some regions of Russia, Kazakhstan, Mongolia, and China, each having quite extensive range. In recent decades, the dwarf hamsters became widely spread all over the world, initially as laboratory animals and later as popular pets. By now, there is lot of decorative breed lines and colored forms of these animals. Comparison of mtDNA nucleotide sequences of dwarf hamsters acquired in pet shops of some countries in Europe, South-East Asia and North America with distribution of mtDNA haplotypes within natural ranges showed the limitation of decorative line founders' points of origin by one region for each of the species. All haplotypes found in decorative Dzungarian hamsters (Ph. sungorus) purchased ounside Russia coincide with or are significantly close to haplotypes spread in the southern part of West Siberia (Russia) and adjacent regions of Kazakhstan; haplotypes of decorative Campbell's hamster (Ph. campbelli) belong to haplogroup of this species natural populations inhabiting South Tyva (Russia); and all studied decorative Desert hamsters (Ph. roborovskii) had one hapotype specific for South-Eastern Kazakhstan. The review of the history of researches on dwarf hamsters biology allows to determine delivery of hamsters from mentioned regions to scientific laboratories and zoos by certain expeditions and/or researchers. Unlike hamsters with natural hair color, the colored hamsters have no normal hair. Their hair is dull and straggly. The hair differentiation (presence of different hair types and their size characteristics) gets broken and results in deformation, bending, and splitting of the shaft, cracks in cuticle, change of configuration and location of medulla, uneven development of cortex. It is assumed that these destructive changes are associated with genetic characteristics of these hamsters' colored forms.

Human Macrophages and Dendritic Cells Can Equally Present MART-1 Antigen to CD8+ T Cells after Phagocytosis of Gamma-Irradiated Melanoma Cells

PubMed Central

Barrio, María Marcela; Abes, Riad; Colombo, Marina; Pizzurro, Gabriela; Boix, Charlotte; Roberti, María Paula; Gélizé, Emmanuelle; Rodriguez-Zubieta, Mariana

2012-01-01

Dendritic cells (DC) can achieve cross-presentation of naturally-occurring tumor-associated antigens after phagocytosis and processing of dying tumor cells. They have been used in different clinical settings to vaccinate cancer patients. We have previously used gamma-irradiated MART-1 expressing melanoma cells as a source of antigens to vaccinate melanoma patients by injecting irradiated cells with BCG and GM-CSF or to load immature DC and use them as a vaccine. Other clinical trials have used IFN-gamma activated macrophage killer cells (MAK) to treat cancer patients. However, the clinical use of MAK has been based on their direct tumoricidal activity rather than on their ability to act as antigen-presenting cells to stimulate an adaptive antitumor response. Thus, in the present work, we compared the fate of MART-1 after phagocytosis of gamma-irradiated cells by clinical grade DC or MAK as well as the ability of these cells to cross present MART-1 to CD8+ T cells. Using a high affinity antibody against MART-1, 2A9, which specifically stains melanoma tumors, melanoma cell lines and normal melanocytes, the expression level of MART-1 in melanoma cell lines could be related to their ability to stimulate IFN-gamma production by a MART-1 specific HLA-A*0201-restricted CD8+ T cell clone. Confocal microscopy with Alexa Fluor®647-labelled 2A9 also showed that MART-1 could be detected in tumor cells attached and/or fused to phagocytes and even inside these cells as early as 1 h and up to 24 h or 48 h after initiation of co-cultures between gamma-irradiated melanoma cells and MAK or DC, respectively. Interestingly, MART-1 was cross-presented to MART-1 specific T cells by both MAK and DC co-cultured with melanoma gamma-irradiated cells for different time-points. Thus, naturally occurring MART-1 melanoma antigen can be taken-up from dying melanoma cells into DC or MAK and both cell types can induce specific CD8+ T cell cross-presentation thereafter. PMID:22768350

Circadian body temperature variability is an indicator of poor prognosis in cardiomyopathic hamsters.

PubMed

Ahmed, Amany; Gondi, Sreedevi; Cox, Casey; Wang, Suwei; Stupin, Igor V; Shankar, K J; Munir, Shahzeb M; Sobash, Ed; Brewer, Alan; Ferguson, James J; Elayda, Macarthur A; Casscells, S Ward; Wilson, James M

2010-03-01

Low body temperature is an independent predictor of poor prognosis in patients with congestive heart failure. The cardiomyopathic hamster develops progressive biventricular dysfunction, resulting in heart failure death at 9 months to 1 year of life. Our goal was to use cardiomyopathic hamsters to examine the relationship between body temperature and heart failure decompensation and death. To this end, we implanted temperature and activity transducers with telemetry into the peritoneal space of 46 male Bio-TO-2 Syrian cardiomyopathic hamsters. Multiple techniques, including computing mean temperature, frequency domain analysis, and nonlinear analysis, were used to determine the most useful method for predicting poor prognosis. Data from 44 hamsters were included in our final analysis. We detected a decline in core body temperature in 98% of the hamsters 8+/-4 days before death (P < .001). We examined the dominant frequency of temperature variation (ie, the circadian rhythm) by using cosinor analysis, which revealed a significant decrease in the amplitude of the body temperature circadian rhythm 8 weeks before death (0.28 degrees C; 95% CI, 0.26-0.31) compared to baseline (0.36 degrees C; 95% CI, 0.34-0.39; P=.005). The decline in the circadian temperature variation preceded all other evidence of decompensation. We conclude that a decrease in the amplitude of the body temperature circadian rhythm precedes fatal decompensation in cardiomyopathic hamsters. Continuous temperature monitoring may be useful in predicting preclinical decompensation in patients with heart failure and in identifying opportunities for therapeutic intervention. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Evaluation of the mutagenic and cytotoxic effects of mercurous chloride by the micronuclei technique in golden Syrian hamsters.

PubMed

Cortés-Gutiérrez, Elva I; Cerda-Flores, Ricardo M; González-Ramírez, Diego; Zúñiga-Charles, Miguel A; Lazcano-Martínez, Sigifredo; Sampayo-Reyes, Adriana; Leal-Garza, Carlos H

2004-05-01

The aims of this study were to evaluate the mutagenic and cytotoxic activity of mercurous chloride by the micronucleus technique in vivo on the bone marrow of golden Syrian hamsters after a single i.p. drug administration. Forty male golden Syrian hamsters were classified into eight groups: negative control, positive control and six groups treated with different doses of mercurous chloride (1.25, 2.5, 5, 10, 20 and 40 mg/kg). The negative control was injected with physiological saline i.p. and the positive control with cyclophosphamide at a dose of 80 mg/kg i.p. With respect to mutagenic effect, the average number of micronucleated polychromatic erythrocytes (MPE) in hamsters treated with different doses of mercurous chloride was not significant compared with the negative control. With respect to cytotoxic effect, the average polychromatic erythrocyte/red blood cell ratio showed a significant decrease when the doses were higher than the 2.5 mg/kg dose compared with the negative control. In conclusion, this preliminary study shows a cytotoxic effect but not a mutagenic effect of calomel in vivo at one time point (24 h).

Effects of fotemustine or dacarbasine on a melanoma cell line pretreated with therapeutic proton irradiation

PubMed Central

Ristić-Fira, Aleksandra M; Korićanac, Lela B; Žakula, Jelena J; Valastro, Lucia M; Iannolo, Gioacchin; Privitera, Giuseppe; Cuttone, Giacomo; Petrović, Ivan M

2009-01-01

Background Considering that HTB140 melanoma cells have shown a poor response to either protons or alkylating agents, the effects of a combined use of these agents have been analysed. Methods Cells were irradiated in the middle of the therapeutic 62 MeV proton spread out Bragg peak (SOBP). Irradiation doses were 12 or 16 Gy and are those frequently used in proton therapy. Four days after irradiation cells were treated with fotemustine (FM) or dacarbazine (DTIC). Drug concentrations were 100 and 250 μM, values close to those that produce 50% of growth inhibition. Cell viability, proliferation, survival and cell cycle distribution were assessed 7 days after irradiation that corresponds to more than six doubling times of HTB140 cells. In this way incubation periods providing the best single effects of drugs (3 days) and protons (7 days) coincided at the same time. Results Single proton irradiations have reduced the number of cells to ~50%. FM caused stronger cell inactivation due to its high toxicity, while the effectiveness of DTIC, that was important at short term, almost vanished with the incubation of 7 days. Cellular mechanisms triggered by proton irradiation differently influenced the final effects of combined treatments. Combination of protons and FM did not improve cell inactivation level achieved by single treatments. A low efficiency of the single DTIC treatment was overcome when DTIC was introduced following proton irradiation, giving better inhibitory effects with respect to the single treatments. Most of the analysed cells were in G1/S phase, viable, active and able to replicate DNA. Conclusion The obtained results are the consequence of a high resistance of HTB140 melanoma cells to protons and/or drugs. The inactivation level of the HTB140 human melanoma cells after protons, FM or DTIC treatments was not enhanced by their combined application. PMID:19358719

Effects of fotemustine or dacarbasine on a melanoma cell line pretreated with therapeutic proton irradiation.

PubMed

Ristić-Fira, Aleksandra M; Korićanac, Lela B; Zakula, Jelena J; Valastro, Lucia M; Iannolo, Gioacchin; Privitera, Giuseppe; Cuttone, Giacomo; Petrović, Ivan M

2009-04-09

Considering that HTB140 melanoma cells have shown a poor response to either protons or alkylating agents, the effects of a combined use of these agents have been analysed. Cells were irradiated in the middle of the therapeutic 62 MeV proton spread out Bragg peak (SOBP). Irradiation doses were 12 or 16 Gy and are those frequently used in proton therapy. Four days after irradiation cells were treated with fotemustine (FM) or dacarbazine (DTIC). Drug concentrations were 100 and 250 microM, values close to those that produce 50% of growth inhibition. Cell viability, proliferation, survival and cell cycle distribution were assessed 7 days after irradiation that corresponds to more than six doubling times of HTB140 cells. In this way incubation periods providing the best single effects of drugs (3 days) and protons (7 days) coincided at the same time. Single proton irradiations have reduced the number of cells to approximately 50%. FM caused stronger cell inactivation due to its high toxicity, while the effectiveness of DTIC, that was important at short term, almost vanished with the incubation of 7 days. Cellular mechanisms triggered by proton irradiation differently influenced the final effects of combined treatments. Combination of protons and FM did not improve cell inactivation level achieved by single treatments. A low efficiency of the single DTIC treatment was overcome when DTIC was introduced following proton irradiation, giving better inhibitory effects with respect to the single treatments. Most of the analysed cells were in G1/S phase, viable, active and able to replicate DNA. The obtained results are the consequence of a high resistance of HTB140 melanoma cells to protons and/or drugs. The inactivation level of the HTB140 human melanoma cells after protons, FM or DTIC treatments was not enhanced by their combined application.

Irradiation and measurements of fluorinated ethylene-propylene-A on silicon solar cells in vacuum

NASA Technical Reports Server (NTRS)

Marsik, S. J.; Broder, J. D.

1975-01-01

Silicon monoxide (SiO) coated silicon solar cells covered with fluorinated ethylene-propylene-A (FEP-A) were irradiated by 1-MeV electrons in vacuum. The effect of irradiation on the light transmittance of FEP-A was checked by measuring the short-circuit current of the cells while in vacuum after each dose increment, immediately after the irradiation, and again after a minimum elapsed time of 16 hr. The results indicated no apparent loss in transmission due to irradiation of FEP-A and no delamination from the SiO surface while the cells were in vacuum, but embrittlement of FEP-A occurred at the accumulated dose.