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

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

T cells are not required for pathogenesis in the Syrian hamster model of hantavirus pulmonary syndrome.

PubMed

Hammerbeck, Christopher D; Hooper, Jay W

2011-10-01

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.

Effects of 13 T Static Magnetic Fields (SMF) in the Cell Cycle Distribution and Cell Viability in Immortalized Hamster Cells and Human Primary Fibroblasts Cells

NASA Astrophysics Data System (ADS)

Zhao, Guoping; Chen, Shaopeng; Zhao, Ye; Zhu, Lingyan; Huang, Pei; Bao, Lingzhi; Wang, Jun; Wang, Lei; Wu, Lijun; Wu, Yuejin; Xu, An

2010-02-01

Magnetic resonance image (MRI) systems with a much higher magnetic flux density were developed and applied for potential use in medical diagnostic. Recently, much attention has been paid to the biological effects of static, strong magnetic fields (SMF). With the 13 T SMF facility in the Institute of Plasma Physics, Chinese Academy of Sciences, the present study focused on the cellular effects of the SMF with 13 T on the cell viability and the cell cycle distribution in immortalized hamster cells, such as human-hamster hybrid (AL) cells, Chinese hamster ovary (CHO) cells, DNA double-strand break repair deficient mutant (XRS-5) cells, and human primary skin fibroblasts (AG1522) cells. It was found that the exposure of 13 T SMF had less effect on the colony formation in either nonsynchronized or synchronized AL cells. Moreover, as compared to non-exposed groups, there were slight differences in the cell cycle distribution no matter in either synchronized or nonsynchronized immortalized hamster cells after exposure to 13 T SMF. However, it should be noted that the percentage of exposed AG1522 cells at G0/G1 phase was decreased by 10% as compared to the controls. Our data indicated that although 13 T SMF had minimal effects in immortalized hamster cells, the cell cycle distribution was slightly modified by SMF in human primary fibroblasts.

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.

A unique mitigator sequence determines the species specificity of the major late promoter in adenovirus type 12 DNA.

PubMed Central

Zock, C; Iselt, A; Doerfler, W

1993-01-01

Human adenovirus type 12 (Ad12) cannot replicate in hamster cells, whereas human cells are permissive for Ad12. Ad12 DNA replication and late-gene and virus-associated RNA expression are blocked in hamster cells. Early Ad12 genes are transcribed, and the viral DNA can be integrated into the host genome. Ad12 DNA replication and late-gene transcription can be complemented in hamster cells by E1 functions of Ad2 or Ad5, for which hamster cells are fully permissive (for a review, see W. Doerfler, Adv. Virus Res. 39:89-128, 1991). We have previously demonstrated that a 33-nucleotide mitigator sequence, which is located in the downstream region of the major late promoter (MLP) of Ad12 DNA, is responsible for the inactivity of the Ad12 MLP in hamster cells (C. Zock and W. Doerfler, EMBO J. 9:1615-1623, 1990). A similar negative regulator has not been found in the MLP of Ad2 DNA. We have now studied the mechanism of action of this mitigator element. The results of nuclear run-on experiments document the absence of MLP transcripts in the nuclei of Ad12-infected BHK21 hamster cells. Surprisingly, the mitigator element cannot elicit its function in in vitro transcription experiments with nuclear extracts from both hamster BHK21 and human HeLa cells. Intact nuclear topology and/or tightly bound nuclear elements that cannot be eluted in nuclear extracts are somehow required for recognition of the Ad12 mitigator. Electrophoretic mobility shift assays have not revealed significant differences in the binding of proteins from human HeLa or hamster BHK21 cells to the mitigator sequence in the MLP of Ad12 DNA or to the corresponding sequence in Ad2 DNA. We have converted the sequence of the mitigator in the MLP of Ad12 DNA to the equivalent sequence in the MLP of Ad2 DNA by site-directed mutagenesis. This construct was not active in hamster cells. When the Ad12 mitigator, on the other hand, was inserted into the Ad2 MLP, the latter's function in hamster cells was not compromised. Deletions in the 5' upstream region of the Ad12 MLP have provided evidence for the existence of additional sequences that codetermine the deficiency of the Ad12 MLP in hamster cells. The amphifunctional YY1 protein from HeLa cells can bind specifically to the mitigator and to upstream elements of the MLP of Ad12 DNA.(ABSTRACT TRUNCATED AT 400 WORDS) Images PMID:8419643

EMODIN DOWNREGULATES CELL PROLIFERATION MARKERS DURING DMBA INDUCED ORAL CARCINOGENESIS IN GOLDEN SYRIAN HAMSTERS.

PubMed

Manimaran, Asokan; Buddhan, Rajamanickam; Manoharan, Shanmugam

2017-01-01

Cell-cycle disruption is the major characteristic features of neoplastic transformation and the status of cell-cycle regulators can thus be utilized to assess the prognostic significance in patients with cancer. The PCNA, cyclin D1, CDK4, CDK6 and survivin expression in the buccal mucosa was utilized to evaluate the Emodin efficacy on abnormal cell proliferation during 7,12-dimethylbenz(a)anthracene (DMBA) induced oral carcinogenesis in golden Syrian hamsters. Topical application of DMBA, three times a week for 14 weeks, on the hamsters' buccal pouches developed well differentiated squamous cell carcinoma. Cyclin D1 and PCNA over-expression and up-regulation of CDK4, CDK6 and survivin were noticed in the buccal mucosa of hamsters treated with DMBA alone. Emodin administration (50mg/kg b.w) orally to hamsters treated with DMBA down-regulated the expression of cell proliferation markers in the buccal mucosa. The anti-cell proliferative role of Emodin is owing to its modulating efficacy on cell-cycle markers towards the tumor suppression during DMBA induced oral carcinogenesis.

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

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

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

Rapid endocytosis of the low density lipoprotein receptor-related protein modulates cell surface distribution and processing of the beta-amyloid precursor protein.

PubMed

Cam, Judy A; Zerbinatti, Celina V; Li, Yonghe; Bu, Guojun

2005-04-15

The low density lipoprotein receptor-related protein (LRP) is a approximately 600-kDa multifunctional endocytic receptor that is highly expressed in the brain. LRP and its ligands apolipoprotein E, alpha2-macroglobulin, and beta-amyloid precursor protein (APP), are genetically linked to Alzheimer disease and are found in characteristic plaque deposits in brains of patients with Alzheimer disease. To identify which extracellular domains of LRP interact with APP, we used minireceptors of each of the individual LRP ligand binding domains and assessed their ability to bind and degrade a soluble APP fragment. LRP minireceptors containing ligand binding domains II and IV, but not I or III, interacted with APP. To test whether APP trafficking is directly related to the rapid endocytosis of LRP, we generated stable Chinese hamster ovary cell lines expressing either a wild-type LRP minireceptor or its endocytosis mutants. Chinese hamster ovary cells stably expressing wild-type LRP minireceptor had less cell surface APP than pcDNA3 vector-transfected cells, whereas those stably expressing endocytosis-defective LRP minireceptors accumulated APP at the cell surface. We also found that the steady-state levels of the amyloid beta-peptides (Abeta) is dictated by the relative expression levels of APP and LRP, probably reflecting the dual roles of LRP in both Abeta production and clearance. Together, these data establish a relationship between LRP rapid endocytosis and APP trafficking and proteolytic processing to generate Abeta.

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

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.

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.

Molecular Biology: Conference on Genetic Engineering Techniques (2nd) Held in London (United Kingdom) on 20-21 November 1986.

DTIC Science & Technology

1987-05-27

system in Chinese t-PA to be a serine protease of 327 amino ovary hamster cells. Precise yields from acids in length. The protein appears, high-level...ham- ster or mouse cell line, allowing the differentiation of human and hamster or ________ mouse clones by hybridization with total human DNA or...appropriate lo- functional protein when transferred into cation downstream of a strong promoter in baby hamster kidney (BHK) cells or rat place of one or

Newly identified CHO ERCC3/XPB mutations and phenotype characterization

PubMed Central

Rybanská, Ivana; Gurský, Ján; Fašková, Miriam; Salazar, Edmund P.; Kimlíčková-Polakovičová, Erika; Kleibl, Karol; Thompson, Larry H.; Piršel, Miroslav

2010-01-01

Nucleotide excision repair (NER) is a complex multistage process involving many interacting gene products to repair a wide range of DNA lesions. Genetic defects in NER cause human hereditary diseases including xeroderma pigmentosum (XP), Cockayne syndrome (CS), trichothiodystrophy and a combined XP/CS overlapping symptom. One key gene product associated with all these disorders is the excision repair cross-complementing 3/xeroderma pigmentosum B (ERCC3/XPB) DNA helicase, a subunit of the transcription factor IIH complex. ERCC3 is involved in initiation of basal transcription and global genome repair as well as in transcription-coupled repair (TCR). The hamster ERCC3 gene shows high degree of homology with the human ERCC3/XPB gene. We identified new mutations in the Chinese hamster ovary cell ERCC3 gene and characterized the role of hamster ERCC3 protein in DNA repair of ultraviolet (UV)-induced and oxidative DNA damage. All but one newly described mutations are located in the protein C-terminal region around the last intron–exon boundary. Due to protein truncations or frameshifts, they lack amino acid Ser751, phosphorylation of which prevents the 5′ incision of the UV-induced lesion during NER. Thus, despite the various locations of the mutations, their phenotypes are similar. All ercc3 mutants are extremely sensitive to UV-C light and lack recovery of RNA synthesis (RRS), confirming a defect in TCR of UV-induced damage. Their limited global genome NER capacity averages ∼8%. We detected modest sensitivity of ercc3 mutants to the photosensitizer Ro19-8022, which primarily introduces 8-oxoguanine lesions into DNA. Ro19-8022-induced damage interfered with RRS, and some of the ercc3 mutants had delayed kinetics. All ercc3 mutants showed efficient base excision repair (BER). Thus, the positions of the mutations have no effect on the sensitivity to, and repair of, Ro19-8022-induced DNA damage, suggesting that the ERCC3 protein is not involved in BER. PMID:19942596

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

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-sized round/oval or stellate cells. Immunoreactivity for the GluR2/3 was clearly reduced in the contralateral SC following unilateral enucleation in the hamster. By contrast, enucleation appeared to have had no effect on the GluR2/3 immunoreactivity in the cat and rabbit SC. The results indicate that neurons in the mammalian SC express GluR2/3 in specific layers, which does not correlate with the expression of calbindin D28K and parvalbumin among the animals.

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

Altered synthesis and processing of oligosaccharides of vesicular stomatitis virus glycoprotein in different lectin-resistant Chinese hamster ovary cell lines.

PubMed

Hunt, L A

1980-08-01

To determine the particular intracellular steps in the glycosylation of the vesicular stomatitis virus (VSV) glycoprotein that were altered in several lectin-resistant CHO cell lines, VSV-infected parental and mutant cells were pulse-labeled for 30 and 120 min with [3H]mannose and [3H]glucosamine. Cell-associated viral glycopeptides were analyzed by gel filtration combined with specific glycosidase digestions and compared with the corresponding mature virion oligosaccharides. The intracellular glycosylation of the VSV glycoprotein in a mutant cell line resistant to phytohemagglutinin was identical to that in the normal cells except for a complete block in processing at a specific step in the final trimming of the oligomannosyl core from five to three mannoses. The results demonstrated that a double-mutant cell line selected from the phytohemagglutinin-resistant cells for resistance to concanavalin A had an additional defect in one of the earliest stages of glycosylation, resulting in smaller precursor oligosaccharides linked to protein.

Altered synthesis and processing of oligosaccharides of vesicular stomatitis virus glycoprotein in different lectin-resistant Chinese hamster ovary cell lines.

PubMed Central

Hunt, L A

1980-01-01

To determine the particular intracellular steps in the glycosylation of the vesicular stomatitis virus (VSV) glycoprotein that were altered in several lectin-resistant CHO cell lines, VSV-infected parental and mutant cells were pulse-labeled for 30 and 120 min with [3H]mannose and [3H]glucosamine. Cell-associated viral glycopeptides were analyzed by gel filtration combined with specific glycosidase digestions and compared with the corresponding mature virion oligosaccharides. The intracellular glycosylation of the VSV glycoprotein in a mutant cell line resistant to phytohemagglutinin was identical to that in the normal cells except for a complete block in processing at a specific step in the final trimming of the oligomannosyl core from five to three mannoses. The results demonstrated that a double-mutant cell line selected from the phytohemagglutinin-resistant cells for resistance to concanavalin A had an additional defect in one of the earliest stages of glycosylation, resulting in smaller precursor oligosaccharides linked to protein. Images PMID:6255177

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.

Atypical fibrosarcomas derived from cutaneous ganglion cell-like cells in 2 domestic Djungarian hamsters (Phodopus sungorus).

PubMed

Kondo, Hirotaka; Onuma, Mamoru; Shibuya, Hisashi; Sato, Tsuneo; Abbott, Jeffrey R

2011-07-01

Androgen-dependent atypical fibromas are benign tumors derived from ganglion-cell-like cells that are particular to Djungarian hamsters (Phodopus sungorus). Masses excised from 2 hamsters were composed of pleomorphic ganglion cell-like cells supported by small to moderate amounts of collagenous matrix. Intracytoplasmic fibrils were present in silver-stained sections, and immunohistochemistry showed that the cells expressed vimentin, androgen receptor, and, in one case, estrogen receptor α. In contrast to previously reported atypical fibromas, these tumors had features of anaplasia and were locally invasive. We diagnosed the tumors as atypical fibrosarcomas and consider them an unusual malignant counterpart of atypical fibroma. Copyright 2011 by the American Association for Laboratory Animal Science

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.

High intake of saturated fat, but not polyunsaturated fat, improves survival in heart failure despite persistent mitochondrial defects.

PubMed

Galvao, Tatiana F; Brown, Bethany H; Hecker, Peter A; O'Connell, Kelly A; O'Shea, Karen M; Sabbah, Hani N; Rastogi, Sharad; Daneault, Caroline; Des Rosiers, Christine; Stanley, William C

2012-01-01

The impact of a high-fat diet on the failing heart is unclear, and the differences between polyunsaturated fatty acids (PUFA) and saturated fat have not been assessed. Here, we compared a standard low-fat diet to high-fat diets enriched with either saturated fat (palmitate and stearate) or PUFA (linoleic and α-linolenic acids) in hamsters with genetic cardiomyopathy. Male δ-sarcoglycan null Bio TO2 hamsters were fed a standard low-fat diet (12% energy from fat), or high-fat diets (45% fat) comprised of either saturated fat or PUFA. The median survival was increased by the high saturated fat diet (P< 0.01; 278 days with standard diet and 361 days with high saturated fat)), but not with high PUFA (260 days) (n = 30-35/group). Body mass was modestly elevated (∼10%) in both high fat groups. Subgroups evaluated after 24 weeks had similar left ventricular chamber size, function, and mass. Mitochondrial oxidative enzyme activity and the yield of interfibrillar mitochondria (IFM) were decreased to a similar extent in all TO2 groups compared with normal F1B hamsters. Ca(2+)-induced mitochondrial permeability transition pore opening was enhanced in IFM in all TO2 groups compared with F1B hamsters, but to a significantly greater extent in those fed the high PUFA diet compared with the standard or high saturated fat diet. These results show that a high intake of saturated fat improves survival in heart failure compared with a high PUFA diet or low-fat diet, despite persistent mitochondrial defects.

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, ...

MEK-ERK inhibition corrects the defect in VLDL assembly in HepG2 cells: potential role of ERK in VLDL-ApoB100 particle assembly.

PubMed

Tsai, Julie; Qiu, Wei; Kohen-Avramoglu, Rita; Adeli, Khosrow

2007-01-01

Hepatic VLDL assembly is defective in HepG2 cells, resulting in the secretion of immature triglyceride-poor LDL-sized apoB particles. We investigated the mechanisms underlying defective VLDL assembly in HepG2 and have obtained evidence implicating the MEK-ERK pathway. HepG2 cells exhibited considerably higher levels of the ERK1/2 mass and activity compared with primary hepatocytes. Inhibition of ERK1/2 using the MEK1/MEK2 inhibitor, U0126 (but not the inactive analogue) led to a significant increase in apoB secretion. In the presence of oleic acid, ERK1/2 inhibition caused a major shift in the lipoprotein distribution with a majority of particles secreted as VLDL, an effect independent of insulin. In contrast, overexpression of constitutively active MEK1 decreased apoB and large VLDL secretion. MEK1/2 inhibition significantly increased both cellular and microsomal TG mass, and mRNA levels for DGAT-1 and DGAT-2. In contrast to ERK, modulation of the PI3-K pathway or inhibition of the p38 MAP kinase, had no effect on lipoprotein density profile. Modulation of the MEK-ERK pathway in primary hamster hepatocytes led to changes in apoB secretion and altered the density profile of apoB-containing lipoproteins. Inhibition of the overactive ras-MEK-ERK pathway in HepG2 cells can correct the defect in VLDL assembly leading to the secretion of large, VLDL-sized particles, similar to primary hepatocytes, implicating the MEK-ERK cascade in VLDL assembly in the HepG2 model. Modulation of this pathway in primary hepatocytes also regulates apoB secretion and appears to alter the formation of VLDL-1 sized particles.

Serotonergic modulation of hippocampal pyramidal cells in euthermic, cold-acclimated, and hibernating hamsters

NASA Technical Reports Server (NTRS)

Horrigan, D. J.; Horwitz, B. A.; Horowitz, J. M.

1997-01-01

Serotonergic fibers project to the hippocampus, a brain area previously shown to have distinctive changes in electroencephalograph (EEG) activity during entrance into and arousal from hibernation. The EEG activity is generated by pyramidal cells in both hibernating and nonhibernating species. Using the brain slice preparation, we characterized serotonergic responses of these CA1 pyramidal cells in euthermic, cold-acclimated, and hibernating Syrian hamsters. Stimulation of Shaffer-collateral/commissural fibers evoked fast synaptic excitation of CA1 pyramidal cells, a response monitored by recording population spikes (the synchronous generation of action potentials). Neuromodulation by serotonin (5-HT) decreased population spike amplitude by 54% in cold-acclimated animals, 80% in hibernating hamsters, and 63% in euthermic animals. The depression was significantly greater in slices from hibernators than from cold-acclimated animals. In slices from euthermic animals, changes in extracellular K+ concentration between 2.5 and 5.0 mM did not significantly alter serotonergic responses. The 5-HT1A agonist 8-hydroxy-2(di-n-propylamino)tetralin mimicked serotonergic inhibition in euthermic hamsters. Results show that 5-HT is a robust neuromodulator not only in euthermic animals but also in cold-acclimated and hibernating hamsters.

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.

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

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

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.

Species differences in susceptibility to 1,3-dinitrobenzene-induced testicular toxicity and methemoglobinemia.

PubMed

Obasaju, M F; Katz, D F; Miller, M G

1991-02-01

The testicular toxicity and methemoglobinemia induced by 1,3-dinitrobenzene (1,3-DNB) was compared in two species, the Sprague-Dawley rat and the golden Syrian hamster. A marked difference in susceptibility to both endpoints of toxicity was observed. The hamster showed no testicular lesions at dose levels up to 50 mg/kg whereas, as previously reported by others, damage to rat testicular tubules in later stages of spermatogenesis was readily apparent at a 25 mg/kg dose level. Similarly, administration of 1,3-DNB induced substantially less methemoglobinemia in the hamster than in the rat. For example, at the 25 mg/kg dose level peak levels of methemoglobin in the hamster were 15% compared with 80% in the rat. Mortality in the rat also occurred at lower doses than in the hamster (50 vs 100 mg/kg, respectively). In in vitro studies, the capacity of 1,3-DNB and 1,3-DNB metabolites (nitroaniline, nitroacetanilide, aminoacetanilide, diacetamidobenzene) to induce methemoglobinemia was examined in suspensions of red blood cells obtained from both species. Only 1,3-DNB caused the formation of methemoglobin and rat red blood cells were twice as sensitive as hamster red blood cells. The species difference in susceptibility to both methemoglobinemia and testicular toxicity could indicate differences in 1,3-DNB clearance and/or formation of toxic metabolites. Additional metabolic work is under way. This study demonstrates that the hamster is more resistant than the rat to the testicular lesion and methemoglobinemia induced by 1,3-DNB.

Experimental evidence for the origin of ductal-type adenocarcinoma from the islets of Langerhans.

PubMed Central

Pour, P. M.; Weide, L.; Liu, G.; Kazakoff, K.; Scheetz, M.; Toshkov, I.; Ikematsu, Y.; Fienhold, M. A.; Sanger, W.

1997-01-01

To investigate the role of the islets of Langerhans in pancreatic carcinogenesis, freshly isolated islets from male Syrian hamsters were transplanted into the right submandibular glands of 50 female hamsters that were or were not pre-treated with streptozotocin. Thyroid gland fragments, cellulose powder, and immortal hamster pancreatic ductal cells were injected into the left submandibular gland of the same hamsters. All recipient hamsters were then treated with the potent pancreatic carcinogen N-nitrosobis(2-oxopropyl)amine weekly at a dose of 40 mg/kg of body weight for 3 weeks. Between 3 and 8 weeks later, 18 of 75 (24%) hamsters developed large ductal-type adenocarcinomas in the submandibular gland region, where islets were transplanted, but none developed tumors in the left submandibular gland. In 9 of 18 hamsters, tumors were multiple so that a total of 31 cancers were found. Eleven of these carcinomas were in the vicinity of transplanted islets, eight of which showed intra-insular ductular or cyst formation as seen in the pancreas of hamsters during pancreatic carcinogenesis. The formation of ductular structures within islets was also demonstrated in vitro. Some tumor cells in the vicinity of these islets were reactive with anti-insulin. Y chromosome message was found by polymerase chain reaction analysis in one of the three tumors examined. Also, like the induced pancreatic tumors, all three submandibular gland tumors that were examined had the mutation of the c-Ki-ras oncogene at codon 12 and all tumors expressed blood group A antigen. These and other findings strongly suggest that some components of islets, most probably stem cells, are the origin of ductal-type adenocarcinomas in this model. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:9176407

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 pancreatic carcinogenesis. Images Figure 2 Figure 3 Figure 4 PMID:8780405

Pharmacokinetics and pharmacodynamics of tetra(m-hydroxyphenyl)chlorin in the hamster cheek pouch tumor model: comparison with clinical measurements.

PubMed

Glanzmann, T; Forrer, M; Blant, S A; Woodtli, A; Grosjean, P; Braichotte, D; van den Bergh, H; Monnier, P; Wagnières, G

2000-08-01

The pharmacokinetics (PK) of the photosensitizer tetra(m-hydroxyphenyl)chlorin (mTHPC) was measured by optical fiber-based light-induced fluorescence spectroscopy (LIFS) in the normal and tumoral cheek pouch mucosa of 29 Golden Syrian hamsters with chemically induced squamous cell carcinoma. Similar measurements were carried out on the normal oral cavity mucosa of five patients up to 30 days after injection. The drug doses were between 0.15 and 0.3 mg per kg of body weight (mg/kg), and the mTHPC fluorescence in the tissue was excited at 420 nm. The PK in both human and hamster exhibited similar behavior although the PK in the hamster mucosa was slightly delayed in comparison with that of its human counterpart. The mTHPC fluorescence signal of the hamster mucosa was smaller than that of the human mucosa by a factor of about 3 for the same injected drug dose. A linear correlation was found between the fluorescence signal and the mTHPC dose in the range from 0.075 to 0.5 mg/kg at times between 8 and 96 h after injection. No significant selectivity in mTHPC fluorescence between the tumoral and normal mucosa of the hamsters was found at any of the applied conditions. The sensitivity of the normal and tumoral hamster cheek pouch mucosa to mTHPC photodynamic therapy as a function of the light dose was determined by light irradiation at 650 nm and 150 mW/cm2, 4 days after the injection of a drug dose of 0.15 mg/kg. These results were compared with irradiations of the normal oral and normal and tumoral bronchial mucosa of 37 patients under the same conditions. The reaction to PDT of both types of human mucosae was considerably stronger than that of the hamster cheek pouch mucosa. The sensitivity to PDT became comparable between hamster and human mucosa when the drug dose for the hamster was increased to 0.5 mg/kg. A significant therapeutic selectivity between the normal and neoplastic hamster cheek pouch was observed. Less selectivity was found following irradiations of normal mucosa and early carcinomas in the human bronchi. The pharmacodynamic behavior of mTHPC was determined by test irradiations of the normal mucosa of hamsters and patients between 6 h and 8 days after injection of 0.5 and 0.15 mg/kg in the hamsters and the patients, respectively. The normal hamster cheek pouch showed a maximum response to irradiation 6 h after injection and then decreased continuously to no observable reaction at 8 days after injection. The reaction of the normal human oral mucosa, however, showed an increasing sensitivity to the applied light between 6 h and 4 days after mTHPC injection and then decreased again at 8 days. The hamster model with the chemically induced early squamous cell cancer in the cheek pouch thus showed some similarity to the early squamous cell cancer of the human oral mucosa considering the PK. However, a quantitative difference in fluorescence signal for identical mTHPC doses as well as a significant difference in pharmacodynamic behavior were also observed. The suitability of this animal model for the optimization of PDT parameters in the clinic is therefore limited. Hence great care must be taken in screening new dyes for PDT of early squamous cell cancer of the upper aerodigestive tract based upon observables in the hamster cheek pouch model.

Evaluation of Chloropentafluorobenzene in a Battery of in vitro Short Term Assays

DTIC Science & Technology

1986-01-01

metabolic activation. The CHO/HGPRT assay measures the ability of a test agent to induce forward mutations at the enzyme hypoxanthine-guanine...phosphoribosyl transferase (HGPRT) locus of Chinese hamster ovary cells on the basis- that presumptive mutants defective in the enzyme HGPRT are unable to...10 0 4.) $4 coc H4 0 o uE p- ’-’ coQ i u ,q10 t GD 4- r ) c41 uH 0 0 41GD c t Ia) U, 40 r. 4 coV P-1- 41 E-4 0 .Z ~-H 1 0) N Cu I0 m : L0 0 z4v- +10

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

Centrosome Amplification: A Potential Marker of Breast Cancer Agressiveness

DTIC Science & Technology

2006-07-01

centrosome amplification. Introduction of DNA damage in the MCF-7 cell line by treatment with hydroxyurea (HU) or daunorubicin (DR) resulted in the...cycles of DNA synthesis and mitotic division in hydroxyurea - arrested Chinese hamster ovary cells. J Cell Biol, 130: 105-115, 1995. 23. D’Assoro, A. B...from cycles of DNA synthesis and mitotic division in hydroxyurea -arrested Chinese hamster ovary cells. J Cell Biol, 1995. 130(1): p. 105-15. 22

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.

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.

Dicholesteroyl diselenide: cytotoxicity, genotoxicity and mutagenicity in the yeast Saccharomyces cerevisiae and in Chinese hamster lung fibroblasts.

PubMed

de Oliveira, Iuri Marques; Degrandi, Tiago Hoerbe; Jorge, Patrícia Mendes; Saffi, Jenifer; Rosa, Renato Moreira; Guecheva, Temenouga Nikolova; Henriques, João Antonio Pêgas

2014-03-15

The organoselenium compound, dicholesteroyl diselenide (DCDS) is a structural analogue of diphenyl diselenide (DPDS) and may be considered as a promising antioxidant drug in vivo. Nevertheless, little is known about the toxicological properties of DCDS. In the present study we evaluated the cytotoxic, genotoxic and mutagenic properties of DCDS in Chinese hamster lung fibroblasts (V79) and in strains of the yeast Saccharomyces cerevisiae, proficient and deficient in several DNA-repair pathways. The results with V79 cells show that DCDS induced cytotoxicity, GSH depletion and elevation of lipid peroxidation at lower concentrations than did DPDS. DCDS also generated single- and double-strand DNA breaks in V79 cells, both in the presence and in the absence of metabolic activation, as revealed by alkaline and neutral comet assays. Moreover, the induction of oxidative DNA base-damage was demonstrated by means of a modified comet assay with formamidopyrimidine-DNA glycosylase and endonuclease III. Treatment with DCDS also induced micronucleus formation in V79 cells as well as point and frame-shift mutations in a haploid wild-type strain of S. cerevisiae. Yeast mutants defective in base excision-repair proteins were the most sensitive to DCDS. Pre-incubation with N-acetylcysteine reduced DCDS's oxidative, genotoxic and mutagenic effects in yeast and in V79 cells. Our findings indicate that the presence of cholesteroyl substituents in DCDS results in elevation of its cytotoxic and genotoxic potential compared with that of DPDS in yeast and in V79 cells. However, due to dose-dependent contrasting behaviour of organoselenium compounds and differences in their toxicity in in vitro and in vivo systems, further studies are needed in order to establish the non-toxic concentration range for treatment in mammals. Copyright © 2014 Elsevier B.V. All rights reserved.

Primers of glycosaminoglycan biosynthesis from Peruvian rain forest plants.

PubMed

Taylor, W H; Sinha, A; Khan, I A; McDaniel, S T; Esko, J D

1998-08-28

We have developed a rapid, high throughput screening assay for compounds that alter the assembly of glycosaminoglycan chains in Chinese hamster ovary cells. The assay uses autoradiography to measure the binding of newly synthesized [35S]proteoglycans and [35S]glycosaminoglycans to a positively charged membrane. Screening over 1000 extracts from a random plant collection obtained from the Amazon rain forest yielded five plants that stimulated glycosaminoglycan assembly in both wild-type cells and a mutant cell line defective in xylosyltransferase (the first committed enzyme involved in glycosaminoglycan biosynthesis). Fractionation of an extract of Maieta guianensis by silica gel and reverse-phase chromatography yielded two pure compounds with stimulatory activity. Spectroscopic analysis by NMR and mass spectrometry revealed that the active principles were xylosides of dimethylated ellagic acid. One of the compounds also contained a galloyl group at C-3 of the xylose moiety. These findings suggest that plants and other natural products may be a source of agents that can potentially alter glycosaminoglycan and proteoglycan formation in animal cells.

Endocytic function is critical for influenza A virus infection via DC-SIGN and L-SIGN

PubMed Central

Gillespie, Leah; Roosendahl, Paula; Ng, Wy Ching; Brooks, Andrew G.; Reading, Patrick C.; Londrigan, Sarah L.

2016-01-01

The ubiquitous presence of cell-surface sialic acid (SIA) has complicated efforts to identify specific transmembrane glycoproteins that function as bone fide entry receptors for influenza A virus (IAV) infection. The C-type lectin receptors (CLRs) DC-SIGN (CD209) and L-SIGN (CD209L) enhance IAV infection however it is not known if they act as attachment factors, passing virions to other unknown receptors for virus entry, or as authentic entry receptors for CLR-mediated virus uptake and infection. Sialic acid-deficient Lec2 Chinese Hamster Ovary (CHO) cell lines were resistant to IAV infection whereas expression of DC-SIGN/L-SIGN restored susceptibility of Lec2 cells to pH- and dynamin-dependent infection. Moreover, Lec2 cells expressing endocytosis-defective DC-SIGN/L-SIGN retained capacity to bind IAV but showed reduced susceptibility to infection. These studies confirm that DC-SIGN and L-SIGN are authentic endocytic receptors for IAV entry and infection. PMID:26763587

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.

INGN 007, an oncolytic adenovirus vector, replicates in Syrian hamsters but not mice: comparison of biodistribution studies.

PubMed

Ying, B; Toth, K; Spencer, J F; Meyer, J; Tollefson, A E; Patra, D; Dhar, D; Shashkova, E V; Kuppuswamy, M; Doronin, K; Thomas, M A; Zumstein, L A; Wold, W S M; Lichtenstein, D L

2009-08-01

Preclinical biodistribution studies with INGN 007, an oncolytic adenovirus (Ad) vector, supporting an early stage clinical trial were conducted in Syrian hamsters, which are permissive for Ad replication, and mice, which are a standard model for assessing toxicity and biodistribution of replication-defective (RD) Ad vectors. Vector dissemination and pharmacokinetics following intravenous administration were examined by real-time PCR in nine tissues and blood at five time points spanning 1 year. Select organs were also examined for the presence of infectious vector/virus. INGN 007 (VRX-007), wild-type Ad5 and AdCMVpA (an RD vector) were compared in the hamster model, whereas only INGN 007 was examined in mice. DNA of all vectors was widely disseminated early after injection, but decayed rapidly in most organs. In the hamster model, DNA of INGN 007 and Ad5 was more abundant than that of the RD vector AdCMVpA at early times after injection, but similar levels were seen later. An increased level of INGN 007 and Ad5 DNA but not AdCMVpA DNA in certain organs early after injection, and the presence of infectious INGN 007 and Ad5 in lung and liver samples at early times after injection, strongly suggests that replication of INGN 007 and Ad5 occurred in several Syrian hamster organs. There was no evidence of INGN 007 replication in mice. In addition to providing important information about INGN 007, the results underscore the utility of the Syrian hamster as a permissive immunocompetent model for Ad5 pathogenesis and oncolytic Ad vectors.

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.

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 matrix. Repair experiments indicate that in CHO cells repair of DSB in loops containing multiple DSB are repaired with "slow" kinetics (t1/2 = 5 hrs) whilst DSB occurring in loops containing single DSB are repaired with "fast" kinetics (t1/2 " 10 min). Xrs- 5 cells are incapable of repairing these multiply damaged loops. This work indicates that the spatial orientation of DSB in higher order structures of chromatin are a possible factor in the repair of these lesions. By construction of a mathematical model of the process of elution from chromatin loops it was possible to postulate the size of the loops to approximate to 2.5-3 Mbp. Further evidence of a potential structural defect in the chromatin of xrs-5 cells was provided by examination of the polypeptide composition and DNA binding activity of nuclear extracts. The affinity of extracted proteins for double-stranded calf-thymus DNA was measured in nuclear extracts of xrs-5 and CHO cells. There was an alteration in the DNA binding activity of salt extractable proteins from xrs-5 as measured by a filter binding assay. By the use of SDS-PAGE and the technique of South-Western blotting, it was possible to identify the approximate molecular weights of these DNA binding proteins. Differences were found in DNA binding between proteins from CHO and xrs-5 extracts of both non-irradiated and irradiated cells. Two proteins with apparent molecular weights of 32.2 and 31.8 kDa exhibited a lower DNA binding activity in xrs-5 than proteins of similar extracts from CHO. The amount of the 32.2 kDa protein was less in the xrs-5 extracts than in CHO extracts, as measured by Coomassie blue staining. The two proteins have not yet been identified but comprise a major DNA binding activity in CHO extracts obtained by detergent-free extraction procedures. This work provides circumstantial evidence that suggests these two polypeptides may form part of the histone H1 family.

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 reduction was seen in the inactive population. Both BPA-BNCT and beam only elicited a qualitative change in the secretion modality of the granule content. Although further studies are needed to evaluate the subcellular effect of BNCT on mast cell granule secretion, the reduction in cell proliferation induced by BPA-BNCT would be partially due to the decrease in total mast cells in the hamster check pouch. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Vero/BC-F: an efficient packaging cell line stably expressing F protein to generate single round-infectious human parainfluenza virus type 2 vector.

PubMed

Ohtsuka, J; Fukumura, M; Tsurudome, M; Hara, K; Nishio, M; Kawano, M; Nosaka, T

2014-08-01

A stable packaging cell line (Vero/BC-F) constitutively expressing fusion (F) protein of the human parainfluenza virus type 2 (hPIV2) was established for production of the F-defective and single round-infectious hPIV2 vector in a strategy for recombinant vaccine development. The F gene expression has not evoked cytostatic or cytotoxic effects on the Vero/BC-F cells and the F protein was physiologically active to induce syncytial formation with giant polykaryocytes when transfected with a plasmid expressing hPIV2 hemagglutinin-neuraminidase (HN). Transduction of the F-defective replicon RNA into the Vero/BC-F cells led to the release of the infectious particles that packaged the replicon RNA (named as hPIV2ΔF) without detectable mutations, limiting the infectivity to a single round. The maximal titer of the hPIV2ΔF was 6.0 × 10(8) median tissue culture infections dose per ml. The influenza A virus M2 gene was inserted into hPIV2ΔF, and the M2 protein was found to be highly expressed in a human lung cancer cell line after transduction. Furthermore, in vivo airway infection experiments revealed that the hPIV2ΔF was capable of delivering transgenes to hamster tracheal cells. Thus, non-transmissible or single round-infectious hPIV2 vector will be potentially applicable to human gene therapy or recombinant vaccine development.

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.

The role of pancreatic islets in experimental pancreatic carcinogenicity.

PubMed Central

Ishikawa, O.; Ohigashi, H.; Imaoka, S.; Nakai, I.; Mitsuo, M.; Weide, L.; Pour, P. M.

1995-01-01

Our previous studies have suggested that the presence of intact islets is essential for the induction of pancreatic exocrine tumors in the Syrian hamster model. To validate this, we investigated the effect of the carcinogen, N-nitrosobis(2-oxo-propyl)amine (BOP) in hamsters, in which homologous isolated intact islets were transplanted into the submandibular gland (SMG). Freshly isolated pure islets from hamster donors were transplanted into the left SMG of 20 female host hamsters. Ten of these hamsters (group 1) received BOP (40 mg/kg) weekly for 3 weeks. Another 10 hamsters (group 2) were kept untreated. In groups 3 and 4 (10 hamsters each) the salt solution or isolated pancreatic ductal cells, respectively, was injected into the gland. In other groups (10 hamsters each) islets were transplanted into the peri-SMG connective tissue (group 5) or into the renal subcapsular space (group 6). Hamsters of group 1 (40 mg/kg, weekly for 3 weeks) as were group 7 hamsters, which served as BOP-treated controls. All BOP-treated hamsters developed pancreatic lesions. Similar hyperplastic and atypical ductal/ductular proliferation and in situ carcinoma were found in the SMG of many group 1 hamsters. No such lesions were found in the SMG, peri-SMG, or renal subcapsular space of the other groups. Islets appear to be involved in carcinogenicity of BOP. The mechanism is obscure. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7485408

Functional integrins from normal and glycosylation-deficient baby hamster kidney cells. Terminal processing of asparagine-linked oligosaccharides is not correlated with fibronectin-binding activity.

PubMed

Koyama, T; Hughes, R C

1992-12-25

We have examined the properties of the alpha 5 beta 1 integrin of baby hamster kidney (BHK) cells, a ricin-resistant variant Ric14 lacking N-acetylglucosaminyl transferase I, and hence unable to complete assembly of hybrid- or complex-type N-glycans, and BHK cells treated with 1-deoxymannojirimycin (dMM), an inhibitor of Golgi mannosidases involved in the initial processing of N-glycan precursors. Comparable amounts of alpha 5 beta 1 integrin were isolated from these cells by chromatography of detergent extracts on a fibronectin cell-binding fragment affinity column and elution with EDTA. The alpha 5 beta 1 integrin obtained from normal BHK cells by fibronectin affinity chromatography contained mainly endoglycosidase H-resistant oligosaccharides, whereas in RicR14 cells or dMM-treated BHK cells these were entirely endoglycosidase H-sensitive. Analysis of lactoperoxidase labeled or long term biosynthetically 35S-labeled proteins from cultures of normal or glycosylation deficient cells showed similar steady state levels of alpha 5 beta 1 integrin and expression at the cell surface. Pulse-chase experiments in normal BHK cells showed rapid conversion of the alpha 5 subunit into a mature form containing oligosaccharides resistant to endoglycosidase H and slower maturation of a precursor beta 1 subunit, as in other cell types. In Ric14 cells the precursor beta 1 subunit was found to carry glycans larger than the fully processed Man5GlcNAc2 glycan of the mature subunit, indicating that the bulk precursor pool had not been translocated into the cis-Golgi compartment containing mannosidase I. We conclude that in BHK cells terminal oligosaccharide processing of alpha 5 beta 1 integrin subunits is not required for dimer formation, surface expression, and fibronectin binding, and that expression of the glycosylation defect of Ric14 cells on the alpha 5 beta 1 integrin does not account for the reduced adhesiveness of these cells on fibronectin compared with normal and dMM-treated BHK cells.

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

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

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

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.

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.

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.

Brca2 (XRCC11) Deficiency Results in Radioresistant DNA Synthesis and a Higher Frequency of Spontaneous Deletions

PubMed Central

Kraakman-van der Zwet, Maria; Overkamp, Wilhelmina J. I.; van Lange, Rebecca E. E.; Essers, Jeroen; van Duijn-Goedhart, Annemarie; Wiggers, Ingrid; Swaminathan, Srividya; van Buul, Paul P. W.; Errami, Abdellatif; Tan, Raoul T. L.; Jaspers, Nicolaas G. J.; Sharan, Shyam K.; Kanaar, Roland; Zdzienicka, Małgorzata Z.

2002-01-01

We show here that the radiosensitive Chinese hamster cell mutant (V-C8) of group XRCC11 is defective in the breast cancer susceptibility gene Brca2. The very complex phenotype of V-C8 cells is complemented by a single human chromosome 13 providing the BRCA2 gene, as well as by the murine Brca2 gene. The Brca2 deficiency in V-C8 cells causes hypersensitivity to various DNA-damaging agents with an extreme sensitivity toward interstrand DNA cross-linking agents. Furthermore, V-C8 cells show radioresistant DNA synthesis after ionizing radiation, suggesting that Brca2 deficiency affects cell cycle checkpoint regulation. In addition, V-C8 cells display tremendous chromosomal instability and a high frequency of abnormal centrosomes. The mutation spectrum at the hprt locus showed that the majority of spontaneous mutations in V-C8 cells are deletions, in contrast to wild-type V79 cells. A mechanistic explanation for the genome instability phenotype of Brca2-deficient cells is provided by the observation that the nuclear localization of the central DNA repair protein in homologous recombination, Rad51, is reduced in V-C8 cells. PMID:11756561

INGN 007, an oncolytic adenovirus vector, replicates in Syrian hamsters but not mice: comparison of biodistribution studies

PubMed Central

Ying, B; Toth, K; Spencer, JF; Meyer, J; Tollefson, AE; Patra, D; Dhar, D; Shashkova, EV; Kuppuswamy, M; Doronin, K; Thomas, MA; Zumstein, LA; Wold, WSM; Lichtenstein, DL

2012-01-01

Preclinical biodistribution studies with INGN 007, an oncolytic adenovirus (Ad) vector, supporting an early stage clinical trial were conducted in Syrian hamsters, which are permissive for Ad replication, and mice, which are a standard model for assessing toxicity and biodistribution of replication-defective (RD) Ad vectors. Vector dissemination and pharmacokinetics following intravenous administration were examined by real-time PCR in nine tissues and blood at five time points spanning 1 year. Select organs were also examined for the presence of infectious vector/virus. INGN 007 (VRX-007), wild-type Ad5 and AdCMVpA (an RD vector) were compared in the hamster model, whereas only INGN 007 was examined in mice. DNA of all vectors was widely disseminated early after injection, but decayed rapidly in most organs. In the hamster model, DNA of INGN 007 and Ad5 was more abundant than that of the RD vector AdCMVpA at early times after injection, but similar levels were seen later. An increased level of INGN 007 and Ad5 DNA but not AdCMVpA DNA in certain organs early after injection, and the presence of infectious INGN 007 and Ad5 in lung and liver samples at early times after injection, strongly suggests that replication of INGN 007 and Ad5 occurred in several Syrian hamster organs. There was no evidence of INGN 007 replication in mice. In addition to providing important information about INGN 007, the results underscore the utility of the Syrian hamster as a permissive immunocompetent model for Ad5 pathogenesis and oncolytic Ad vectors. PMID:19197322

FATE OF FLUORIDE-INDUCED SUBAMELOBLASTIC CYSTS IN DEVELOPING HAMSTER MOLAR TOOTH GERMS

PubMed Central

Lyaruu, DM; Alberga, JMR; Kwee, NCH; Bervoets, TJM; Bronckers, ALJJ; DenBesten, PK

2016-01-01

White opacities and pits are developmental defects in enamel caused by high intake of fluoride (F) during amelogenesis. We tested the hypothesis that these enamel pits develop at locations where F induces the formation of sub-ameloblastic cysts. We followed the fate of these cysts during molar development over time. Mandibles from hamster pups injected with 20 mg NaF/kg at postnatal day 4 were excised from 1 h after injection till shortly after tooth eruption, 8 days later. Tissues were histologically processed and cysts located and measured. Cysts were formed at early secretory stage and transitional stage of amelogenesis and detected as early 1 h after injection. The number of cysts increased from 1 to almost 4 per molar during the first 16 h post-injection. The size of the cysts was about the same, i.e., 0.46±0.29 ×106 μm3 at 2hr and 0.50±0.35×106 μm3 at 16 h post-injection. By detachment of the ameloblasts the forming enamel surface below the cyst was cell-free the first 16 h post-injection. With time new ameloblasts repopulated and covered the enamel surface in the cystic area. Three days after injection all cysts had disappeared and the integrity of the ameloblastic layer restored. After eruption, white opaque areas with intact enamel surface were found occlusally at similar anatomical locations as late secretory stage cysts were seen pre-eruptively. We conclude that at this moderate F dose, the opaque sub-surface defects with intact surface enamel (white spots) are the consequence of the fluoride-induced cystic lesions formed earlier under the late secretory–transitional stage ameloblasts. PMID:21277565

Chromatid repulsion associated with Roberts/SC phocomelia syndrome is reduced in malignant cells and not expressed in interspecies somatic-cell hybrids.

PubMed Central

Krassikoff, N E; Cowan, J M; Parry, D M; Francke, U

1986-01-01

Different cell types from a female patient with Roberts/SC phocomelia syndrome were evaluated quantitatively for the presence of repulsion of heterochromatin and satellite regions of mitotic chromosomes. Whereas EBV-transformed lymphoblasts from an established cell line revealed these phenomena at frequencies equal to those in PHA-stimulated lymphocytes and cultured skin fibroblasts, aneuploid cells from a metastatic melanoma displayed them at 50% lower frequency. Cocultivation of the patient's fibroblasts with either an immortal Chinese hamster cell line or with a human male fibroblast strain carrying a t(4;6)(p14;q21) translocation showed that the phenomenon was not corrected or induced by a diffusible factor or by cell-to-cell contact. In each experiment, only the patient's metaphase spreads revealed chromatid repulsion. In fusion hybrids between the patient's fibroblasts and an established Chinese hamster cell line, the human chromosomes behaved perfectly normally, suggesting that the gene product which is missing or mutant in Roberts/SC phocomelia syndrome is supplied by the Chinese hamster genome. Images Fig. 1 Fig. 2 Fig. 3 PMID:3788975

Parent-of-origin growth effects and the evolution of hybrid inviability in dwarf hamsters.

PubMed

Brekke, Thomas D; Good, Jeffrey M

2014-11-01

Mammalian hybrids often show abnormal growth, indicating that developmental inviability may play an important role in mammalian speciation. Yet, it is unclear if this recurrent phenotype reflects a common genetic basis. Here, we describe extreme parent-of-origin-dependent growth in hybrids from crosses between two species of dwarf hamsters, Phodopus campbelli and Phodopus sungorus. One cross type resulted in massive placental and embryonic overgrowth, severe developmental defects, and maternal death. Embryos from the reciprocal cross were viable and normal sized, but adult hybrid males were relatively small. These effects are strikingly similar to patterns from several other mammalian hybrids. Using comparative sequence data from dwarf hamsters and several other hybridizing mammals, we argue that extreme hybrid growth can contribute to reproductive isolation during the early stages of species divergence. Next, we tested if abnormal growth in hybrid hamsters was associated with disrupted genomic imprinting. We found no association between imprinting status at several candidate genes and hybrid growth, though two interacting genes involved in embryonic growth did show reduced expression in overgrown hybrids. Collectively, our study indicates that growth-related hybrid inviability may play an important role in mammalian speciation but that the genetic underpinnings of these phenotypes remain unresolved. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

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.

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.

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

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 genomics studies. PMID:25398096

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.

Acute toxic effects of single dose dacarbazine: hematological and histological changes in an animal model.

PubMed

Milijašević, B; Stefanović, D; Lalić-Popović, M; Tomić, Z; Kolarović, J; Lalošević, D; Mikov, M

2014-11-01

Treatment of advanced soft tissue sarcoma usually includes dacarbazine (DTIC), an alkylating agent that methylates DNA and is active during all phases of the cell cycle. Common side effects of DTIC include nausea, vomiting, impaired liver and kidney function, myelosuppression, and pneumonia. There are no accounts, however, of histological and hematological changes caused by DTIC. We investigated acute hematological and morphological changes in different organs and in tumors that were caused by a single dose of DTIC. Adult Syrian golden hamsters were inoculated with a suspension of tumorigenic baby hamster kidney (BHK) cells by subcutaneous injection. On day 14 after inoculation, doses of 1.4, 1.6, 1.8 or 2.0 g/m(2) DTIC were injected intraperitoneally into the hamsters. Hamsters in the control group were injected with physiological saline in the same way. Seven days after drug or saline injection the animals were sacrificed and samples of blood, heart, kidney, liver, lungs, spleen, small intestine and tumor were excised, processed and analyzed. Mitoses were counted using an ocular extension with engraved frame. Anemia, thrombocytopenia and leukocytosis were found in the control group of hamsters with fibrosarcoma, whereas animals with fibrosarcoma treated with DTIC developed anemia, thrombocytopenia and leukopenia. Severe pneumonia and moderate hepatitis were detected in all DTIC treated groups. Effects of DTIC on tumor cells included rounding and enlargement of nuclei and rarefaction of chromatin. The number of mitoses was reduced with increasing doses of DTIC. Hepatitis, myelosuppression, pneumonia, and dose-related inhibition of tumor cell proliferation were observed after a single dose of DTIC.

Mutant with diphtheria toxin receptor and acidification function but defective in entry of toxin

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

Kohno, Kenji; Hayes, H.; Mekada, Eisuke

1987-09-01

A mutant of Chinese hamster ovary cells, GE1, that is highly resistant to diphtheria toxin was isolated. The mutant contains 50% ADP-ribosylatable elongation factor 2, but its protein synthesis was not inhibited by the toxin even at concentrations above 100 {mu}g/ml. {sup 125}I-labeled diphtheria toxin was associated with GE1 cells as well as with the parent cells but did not block protein synthesis of GE1 cells even when the cells were exposed to low pH in the presence or absence of NH{sub 4}Cl. The infections of GE1 cells and the parent cells by vesicular stomatitis virus were similar. GE1 cellsmore » were cross-resistant to Pseudomonas aeruginosa exotoxin A and so were about 1,000 times more resistant to this toxin than the parent cells. Hybrids of GE1 cells and the parent cells or mutant cells lacking a functional receptor were more sensitive to diphtheria toxin than GE1 cells. These results suggest that entry of diphtheria toxin into cells requires a cellular factor(s) in addition to those involved in receptor function and acidification of endosomes and that GE1 cells do not express this cellular factor. This character is recessive in GE1 cells.« less

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.

The evolution of chromosomal instability in Chinese hamster cells: a changing picture?

NASA Technical Reports Server (NTRS)

Ponnaiya, B.; Limoli, C. L.; Corcoran, J.; Kaplan, M. I.; Hartmann, A.; Morgan, W. F.

1998-01-01

PURPOSE: To investigate the kinetics of chromosomal instability induced in clones of Chinese hamster cells following X-irradiation. MATERIALS AND METHODS: X-irradiated clones of GM10115, human-hamster hybrid cells containing a single human chromosome 4 (HC4), have been previously established. These clones were defined as unstable if they contained > or = three subpopulations of cells with unique rearrangements of HC4 as detected by FISH. Stable and unstable clones were analysed by FISH and Giemsa staining at various times post-irradiation. RESULTS: While most of the stable clones continued to show chromosomal stability of HC4 over time, one became marginally unstable at approximately 45 population doublings post-irradiation. Clones exhibiting chromosomal instability had one of several fates. Many of the unstable clones were showed similar levels of instability over time. However, one unstable clone became stable with time in culture, while another became even more unstable over time. Cytogenetic analyses of all clones after Giemsa staining indicated that in some clones the hamster chromosomes were rearranged independent of HC4, demonstrating increased frequencies of chromatid breaks and dicentric chromosomes. The majority of the unstable clones also had higher yields of chromatid gaps. CONCLUSIONS: These data demonstrate the dynamic nature of chromosomal instability as measured by two different cytogenetic assays.

Transgene Expression and Host Cell Responses to Replication-Defective, Single-Cycle, and Replication-Competent Adenovirus Vectors.

PubMed

Crosby, Catherine M; Barry, Michael A

2017-02-18

Most adenovirus (Ad) vectors are E1 gene deleted replication defective (RD-Ad) vectors that deliver one transgene to the cell and all expression is based on that one gene. In contrast, E1-intact replication-competent Ad (RC-Ad) vectors replicate their DNA and their transgenes up to 10,000-fold, amplifying transgene expression markedly higher than RD-Ad vectors. While RC-Ad are more potent, they run the real risk of causing adenovirus infections in vector recipients and those that administer them. To gain the benefits of transgene amplification, but avoid the risk of Ad infections, we developed "single cycle" Ad (SC-Ad) vectors. SC-Ads amplify transgene expression and generated markedly stronger and more persistent immune responses than RD-Ad as expected. However, they also unexpectedly generated stronger immune responses than RC-Ad vectors. To explore the basis of this potency here, we compared gene expression and the cellular responses to infection to these vectors in vitro and in vivo. In vitro, in primary human lung epithelial cells, SC- and RC-Ad amplified their genomes more than 400-fold relative to RD-Ad with higher replication by SC-Ad. This replication translated into higher green fluorescent protein (GFP) expression for 48 h by SC- and RC-Ad than by RD-Ad. In vitro, in the absence of an immune system, RD-Ad expression became higher by 72 h coincident with cell death mediated by SC- and RC-Ad and release of transgene product from the dying cells. When the vectors were compared in human THP-1 Lucia- interferon-stimulated gene (ISG) cells, which are a human monocyte cell line that have been modified to quantify ISG activity, RC-Ad6 provoked significantly stronger ISG responses than RD- or SC-Ad. In mice, intravenous or intranasal injection produced up to 100-fold genome replication. Under these in vivo conditions in the presence of the immune system, luciferase expression by RC and SC-Ad was markedly higher than that by RD-Ad. In immunodeficient mice, SC-Ad drove stronger luciferase expression than RC- or RD-Ad. These data demonstrate better transgene expression by SC- and RC-Ad in vitro and in vivo than RD-Ad. This higher expression by the replicating vectors results in a peak of expression within 1 to 2 days followed by cell death of infected cells and release of transgene products. While SC- and RC-Ad expression were similar in mice and in Syrian hamsters, RC-Ad provoked much stronger ISG induction which may explain in part SC-Ad's ability to generate stronger and more persistent immune responses than RC-Ad in Ad permissive hamsters.

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

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.

Triphenyltin impairs a protein kinase A (PKA)-dependent increase of cytosolic Na{sup +} and Ca{sup 2+} and PKA-independent increase of cytosolic Ca{sup 2+} associated with insulin secretion in hamster pancreatic {beta}-cells

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

Miura, Yoshikazu; Matsui, Hisao

2006-11-01

Oral administration of triphenyltin chloride (TPT) (60 mg/kg body weight) inhibits the insulin secretion by decreasing the cytoplasmic Ca{sup 2+} concentration ([Ca{sup 2+}] {sub i}) induced by glucose-dependent insulinotropic polypeptide (GIP) in pancreatic {beta}-cells of the hamster. To test the possibility that the abnormal level of [Ca{sup 2+}] {sub i} induced by TPT administration could be due to a defect in the cAMP-dependent cytoplasmic Na{sup +} concentration ([Na{sup +}] {sub i}) in the {beta}-cells, we investigated the effects of TPT administration on the changes of [Na{sup +}] {sub i} induced by GIP, glucagon-like peptide-1 (GLP-1), or forskolin, an activator ofmore » adenylyl cyclase, and on the changes of [Na{sup +}] {sub i} or [Ca{sup 2+}] {sub i} induced by 6-Bnz-cAMP, an activator of protein kinase A (PKA), and 8-pCPT-2'-O-Me-cAMP, an activator of Epac. The [Na{sup +}] {sub i} and [Ca{sup 2+}] {sub i} were measured in islet cells loaded with sodium-binding benzofuran isophthalate (SBFI) and fura-2, respectively. In the presence of 135 mM Na{sup +}, TPT administration significantly reduced the rise in [Na{sup +}] {sub i} by 10 nM GLP-1, 10 {mu}M forskolin, and 50 {mu}M 6-Bnz-cAMP, but had not effect in a Na{sup +}-free medium. In the presence of 135 mM Na{sup +}, TPT administration also reduced the rise in [Ca{sup 2+}] {sub i} by 8-pCPT-2'-O-Me-cAMP plus10 {mu}M H-89, a inhibitor of PKA, and 6-Bnz-cAMP. Moreover, TPT administration significantly reduced the insulin secretion by 2 mM db-cAMP, GLP-1, GIP, and 8-pCPT-2'-O-Me-cAMP with and without H-89, and that by 6-Bnz-cAMP and forskolin. Our study suggested that TPT has inhibitory effects on the cellular Ca{sup 2+} response due to a reduced Na{sup +} permeability through PKA-dependent mechanisms in hamster islet cells. Also TPT has the reduction of [Ca{sup 2+}] {sub i} related to Na{sup +}-dependent insulin secretion after an activation of Epac.« less

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

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...

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.

Pregnancy interceptive efficacy and biological profile of 3-amino-6,7-dimethoxy-1H-pyrazolo [3,4-b] quinoline (compound 85/83) in rodents.

PubMed

Mehrotra, P K; Shukla, R; Dwivedi, A; Srivastava, R P; Bhat, N; Seth, M; Bhaduri, A P; Kamboj, V P

1991-05-01

Administration of compound 85/83 during the peri- and post-implantation period intercepted pregnancy in hamster and guinea pig by parenteral route and in hamster by oral route also. The m.e.d. for hamster and guinea pig was 10 and 20 mg/kg, respectively; lower doses were less effective. Restricting the administration to early post-implantation schedule interrupted pregnancy partially in both species. The compound was, however, ineffective in rat and in the pre-implantation schedule (days 1-4 post-coitum) in hamster. When tested in vitro on growing trophoblasts at 13.8 x 10(-5) M concentration, it prevented growth and caused degeneration of the cells within 24 h; lower concentration (9.2 x 10(-5) M) was less effective. The compound was found to be devoid of estrogenic, antiestrogenic, progestational and antiprogestational properties in conventional bioassays. In hormone competition assays, its relative binding affinity (RBA) to estrogen receptor was negligible (0.002% of estradiol-17 beta), while for uterine cytosol progesterone receptors in rabbit and hamster was 0.06 and 0.08% of progesterone, respectively. The compound 85/83 appears to intercept pregnancy by interfering with development of trophoblast cells.

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 poised to defend against hantavirus infection, but those antiviral responses may also contribute to hantavirus disease. Here, we demonstrate that, like in our prior T and B cell studies, alveolar macrophages neither prevent hantavirus infection nor cause hantavirus disease. While these studies reflect pathogenesis in the hamster model, they should help us rule out specific cell types and prompt us to consider other potential mechanisms of disease in an effort to improve the outcome of human HPS. Copyright © 2016 Hammerbeck et al.

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, alveolar macrophages are poised to defend against hantavirus infection, but those antiviral responses may also contribute to hantavirus disease. Here, we demonstrate that, like in our prior T and B cell studies, alveolar macrophages neither prevent hantavirus infection nor cause hantavirus disease. While these studies reflect pathogenesis in the hamster model, they should help us rule out specific cell types and prompt us to consider other potential mechanisms of disease in an effort to improve the outcome of human HPS. PMID:27099308

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.

Induction of experimental bone metastasis in mice by transfection of integrin alpha 4 beta 1 into tumor cells.

PubMed Central

Matsuura, N.; Puzon-McLaughlin, W.; Irie, A.; Morikawa, Y.; Kakudo, K.; Takada, Y.

1996-01-01

Cell adhesion receptors (eg, integrins and CD44) play an important role in invasion and metastasis during tumor progression. The increase in integrin alpha 4 beta 1 expression on primary melanomas has been reported to significantly correlate with the development of metastases. alpha 4 beta 1 is a cell surface heterodimer that mediates cell-cell and cell-extracellular matrix interactions through adhesion to vascular cell adhesion molecule (VCAM)-1 and to the IIICS region of fibronectin. To test the effects of alpha 4 beta 1 expression on tumor cell metastasis, Chinese hamster ovary cells were transfected with human alpha 4 cDNA. Whereas alpha 4-negative Chinese hamster ovary cells developed only pulmonary metastasis, alpha 4-positive Chinese hamster ovary cells developed bone and pulmonary metastasis in 3 to 4 weeks when injected intravenously into nude mice. Bone metastasis was inhibited by antibody against alpha 4 or VCAM-1. Expression of alpha 3 beta 1, alpha 6 beta 1, or alpha V beta 1 did not induce bone metastasis. Expression of alpha 4 beta 1 also induced bone metastasis in K562 human erythroleukemia cells injected into SCID mice. These results demonstrate that alpha 4 beta 1 can induce tumor cell trafficking to bone, probably via interaction with VCAM-1 that is constitutively expressed on bone marrow stromal cells. Images Figure 1 Figure 3 PMID:8546226

[Hybrids of human and monkey adenoviruses (adeno-adeno hybrids) that can reproduce in monkey cells: biological and molecular genetic peculiarities].

PubMed

Grinenko, N F; Savitskaia, N V; Pashvykina, G V; Al'tshteĭn, A D

2003-06-01

A highly oncogenic monkey adenovirus SA7(C8) facilitates the reproduction of human adenovirus type 2 (Ad2) in monkey cells. Upon mixed infection of monkey cells with both viruses, these viruses recombine producing defective adeno-adeno hybrids Ad2C8 serologically identical to Ad2 and capable of assisting Ad2 to reproduce in monkey cells. Ad2C8 and Ad2 form an intercomplementary pair inseparable in monkey cells. Unlike oncogenic SA7(C8), Ad2C8 is a nononcogenic virus for hamsters but is able to induce tumor antigens of this virus (T and TSTA). Molecular genetic analysis of 68 clones of adeno-adeno hybrids revealed that the left part of their genome consists of Ad2 DNA, and the right part contains no less than 40% of the viral SA7(C8) genome where E2A, E3, and E4 genes are located. Apparently, the products of these genes contribute to the composition of adenoviral tumor antigens, while the E4 gene is involved in complementation of monkey and human adenoviruses and makes a contribution to host range determination of these viruses.

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.

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).

The combination of i-leader truncation and gemcitabine improves oncolytic adenovirus efficacy in an immunocompetent model.

PubMed

Puig-Saus, C; Laborda, E; Rodríguez-García, A; Cascalló, M; Moreno, R; Alemany, R

2014-02-01

Adenovirus (Ad) i-leader protein is a small protein of unknown function. The C-terminus truncation of the i-leader protein increases Ad release from infected cells and cytotoxicity. In the current study, we use the i-leader truncation to enhance the potency of an oncolytic Ad. In vitro, an i-leader truncated oncolytic Ad is released faster to the supernatant of infected cells, generates larger plaques, and is more cytotoxic in both human and Syrian hamster cell lines. In mice bearing human tumor xenografts, the i-leader truncation enhances oncolytic efficacy. However, in a Syrian hamster pancreatic tumor model, which is immunocompetent and less permissive to human Ad, antitumor efficacy is only observed when the i-leader truncated oncolytic Ad, but not the non-truncated version, is combined with gemcitabine. This synergistic effect observed in the Syrian hamster model was not seen in vitro or in immunodeficient mice bearing the same pancreatic hamster tumors, suggesting a role of the immune system in this synergism. These results highlight the interest of the i-leader C-terminus truncation because it enhances the antitumor potency of an oncolytic Ad and provides synergistic effects with gemcitabine in the presence of an immune competent system.

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 splenic B-cell functions remain intact throughout the course of the disease. These findings were further tested by in vitro methods where splenic and lymph node lymphocytes from infected hamsters were examined for their ability to respond to Con A in terms of the induction of antigen non-specific suppressor T cells. The mixing of Con A stimulated splenic or lymph node lymphocytes from infected hamsters was unable to inhibit the primary antibody responses of SRBC as compared to the normal control.(ABSTRACT TRUNCATED AT 400 WORDS) Images Figure 1 PMID:2931353

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.

A Double Selection Approach to Achieve Specific Expression of Toxin Genes for Ovarian Cancer Gene Therapy

DTIC Science & Technology

2006-11-01

fibers that served as the junction for the replacement of the OAdV7 tail domain, as well as other common sequences, is highlighted. The final Ad5Luc1-OvF...Fold increase in luciferase activity vs. Ad5 b Reference CHO Hamster ovary L/N 22 Soudais et al., 2000 RD Rhabdomyosarcoma L/N 1.5 Dmitriev et al., 1998...of OV-3 cells (human ovarian cancer, 23-fold) and CAR-deficient CHO cells (Chinese hamster ovary, 22-fold), suggesting that RD cells do not express

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.

A novel small animal model to study the replication of simian foamy virus in vivo.

PubMed

Blochmann, Rico; Curths, Christoph; Coulibaly, Cheick; Cichutek, Klaus; Kurth, Reinhard; Norley, Stephen; Bannert, Norbert; Fiebig, Uwe

2014-01-05

Preclinical evaluation in a small animal model would help the development of gene therapies and vaccines based on foamy virus vectors. The establishment of persistent, non-pathogenic infection with the prototype foamy virus in mice and rabbits has been described previously. To extend this spectrum of available animal models, hamsters were inoculated with infectious cell supernatant or bioballistically with a foamy virus plasmid. In addition, a novel foamy virus from a rhesus macaque was isolated and characterised genetically. Hamsters and mice were infected with this new SFVmac isolate to evaluate whether hamsters are also susceptible to infection. Both hamsters and mice developed humoral responses to either virus subtype. Virus integration and replication in different animal tissues were analysed by PCR and co-cultivation. The results strongly indicate establishment of a persistent infection in hamsters. These studies provide a further small animal model for studying FV-based vectors in addition to the established models. © 2013 Elsevier Inc. All rights reserved.

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.

[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.

Regional assignment of seven genes on chromosome 1 of man by use of man-Chinese hamster somatic cell hybrids. II. Results obtained after induction of breaks in chromosome 1 by X-irradiation.

PubMed

Burgerhout, W G; Smit, S L; Jongsma, A P

1977-01-01

The position of genes coding for PGD, PPH1, UGPP, GuK1, PGM1, Pep-C, and FH on human chromosome 1 was investigated by analysis of karyotype and enzyme phenotypes in man-Chinese hamster somatic cell hybrids carrying aberrations involving chromosome 1. Suitable hybrid cell lines were obtained by X-irradiation of hybrid cells carrying an intact chromosome 1 and by fusion of human cells from a clonal population carrying a translocation involving chromosome 1 with Chinese hamster cells. The latter human cell population had been isolated following X-irradiation of primary Lesch-Nyhan fibroblasts. In addition, products of de novo chromosome breakage in the investigated hybrid lines were utilized. By integrating the results of these analyses with earlier findings in our laboratory, the following positions of genes are deduced: PGD and PPH1 in 1p36 leads to 1p34; PGM1 in 1p32; UGPP in 1q21 leads to 1q23; GuK1 in 1q31 leads to 1q42; Pep-C in 1q42; and FH in 1qter leads to 1q42.

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

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.

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.

An Arg for Gly substitution at position 31 in the insulin receptor, linked to insulin resistance, inhibits receptor processing and transport.

PubMed

van der Vorm, E R; van der Zon, G C; Möller, W; Krans, H M; Lindhout, D; Maassen, J A

1992-01-05

In a patient with Leprechaunism, we have characterized a new mutation in the insulin receptor substituting Arg for Gly at position 31. The proband, the mother, and the maternal grandfather were heterozygous for the mutation. Fibroblasts of the proband show a strongly reduced number of high affinity insulin receptors on the cell surface, whereas fibroblasts of the healthy mother and grandfather show moderately reduced insulin receptor numbers. In the other family members neither the binding defect nor the Arg31 mutation was found. The Arg31-mutant receptor was overexpressed in Chinese hamster ovary cells. In these cells the mutant alpha beta-proreceptor was not proteolytically cleaved and no transport to the cell surface took place. The proreceptor was unable to bind insulin and to undergo autophosphorylation. In addition, the proreceptor was not recognized by monoclonal antibodies directed against conformation-dependent epitopes. These findings suggest that the Gly31 to Arg31 mutant is involved in the insulin receptor dysfunction seen in the Leprechaun patient. The mutation seems to alter the conformation of the receptor in such way that the transport of the proreceptor to the Golgi compartment, where proteolytical processing occurs, is inhibited.

Retention of secretory proteins in an intermediate compartment and disappearance of the Golgi complex in an END4 mutant of Chinese hamster ovary cells

PubMed Central

1992-01-01

Mutant V.24.1, a member of the End4 complementation group of temperature-sensitive CHO cells, is defective in secretion at the restrictive temperature (Wang, R.-H., P. A. Colbaugh, C.-Y. Kao, E. A. Rutledge, and R. K. Draper. 1990. J. Biol. Chem. 265:20179-20187; Presley, J. F., R. K. Draper, and D. T. Brown. 1991. J. Virol. 65:1332- 1339). We have further investigated the secretory lesion and report three main findings. First, the block in secretion is not due to aberrant folding or oligomerization of secretory proteins in the endoplasmic reticulum because the hemagglutinin of influenza virus folded and oligomerized at the same rate in mutant and parental cells at the restrictive temperature. Second, secretory proteins accumulated in a compartment intermediate between the ER and the Golgi. Several lines of evidence support this conclusion, the most direct being the colocalization by immunofluorescence microscopy of influenza virus hemagglutinin with a 58-kD protein that is known to reside in an intermediate compartment. Third, at the resolution of fluorescence microscopy, the Golgi complex in the mutant cells vanished at the restrictive temperature. PMID:1577851

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

Ultraviolet light induction of diphtheria toxin-resistant mutations in normal and DNA repair-deficient human and Chinese hamster fibroblasts

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

Trosko, J.E.; Schultz, R.S.; Chang, C.C.

1980-01-01

The role on unrepaired DNA lesions in the production of mutations is suspected of contributing to the initiation phase of carcinogenesis. Since the molecular basis of mutagenesis is not understood in eukaryotic cells, development of new genetic markers for quantitative in vitro measurement of mutations for mammalian cells is needed. Furthermore, mammalian cells, genetically deficient for various DNA repair enzymes, will be needed to study the role of unrepaired DNA lesions in mutagenesis. The results in this report relate to preliminary attempts to characterize the diphtheria toxin resistance marker as a useful quantitative genetic marker in human cells and tomore » isolate and characterize various DNA repair-deficient Chinese hamster cells.« less

A combination of liver fluke infection and traditional northeastern Thai foods associated with cholangiocarcinoma development.

PubMed

Sriraj, Pranee; Boonmars, Thidarut; Aukkanimart, Ratchadawan; Songsri, Jiraporn; Sripan, Panupan; Ratanasuwan, Panaratana; Boonjaraspinyo, Sirintip; Wongchalee, Nadchanan; Laummaunwai, Porntip

2016-10-01

Opisthorchis viverrini infection is one of the risk factors for cholangiocarcinoma (CCA) in northeast Thailand, a region with one of the highest reported incidence rates of CCA. The traditional practice of eating raw fish, repeated exposure to liver flukes, and consumption of nitrosamine-contaminated food are major risk factors for CCA. So far, there have been no reports about which northeastern traditional dishes may be involved in CCA development. The present study, thus, investigated the effects of traditional foods. It focused specifically on the consumption of fermented foods in combination with O. viverrini infection in hamsters. Syrian hamsters were divided into six groups: (i) normal hamsters, (ii) O. viverrini infection only and (iii)-(vi) O. viverrini infection plus fermented foods (pla som-fish fermented for 1 day), som wua-fermented beef, som phag-fermented vegetables, and pla ra-fish fermented for 6 months. Syrian hamster livers were used for analysis of histopathological changes through hematoxylin and eosin; Sirius Red; and immunohistostaining for cytokeratin-19, proliferating cell nuclear antigen, and CA19-9. Hamster sera were used for liver and kidney function tests. Results of all O. viverrini-infected groups and fermented food groups showed that histopathological changes consisted primarily of aggregations of inflammatory cells surrounding the hepatic bile duct, especially at the hilar region. However, there was a difference in virulence. Interestingly, aggregations of inflammatory cells, new bile duct formation, and fibrosis were observed in subcapsular hepatic tissue, which correlated to positive immunohistochemical staining and increased liver function test. The present study suggests that fermented food consumption can exacerbate cholangitis and cholangiofibrosis, which are risk factors for cholangiocarcinoma-associated opisthorchiasis.

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

Various heterologous cells exhibit interferon induced transfer of viral resistance.

PubMed

Hughes, T K; Blalock, J E; Baron, S

1978-01-01

Previously it was shown that cocultivation of mouse L and human WISH or baby hamster kidney cells in the presence of mouse interferon resulted in decreased viral yield from both cell species. We now show that this phenomenon also occurs when rabbit kidney and human WISH cells, with their corresponding interferons, are cocultivated with human WISH and baby hamster kidney cells, respectively. This finding increases the number of donor cell types to three. The related finding that monkey VERO and chick embryo cells can be recipients of transferred resistance expands the number of heterologous recipient cell species capable of receiving transferred resistence to five. Not all cell types tested have been shown to function in this transfer system. The fact that VERO cells, which do not produce interferon, are capable of receiving transferred resistence is significant because it indicates that the mechanism of transfer does not involve production or interferon by the recipient cells.

Autonomic deficit not the cause of death in West Nile virus neurological disease.

PubMed

Wang, Hong; Siddharthan, Venkatraman; Hall, Jeffery O; Morrey, John D

2014-02-01

Some West Nile virus (WNV)-infected patients have been reported to manifest disease signs consistent with autonomic dysfunction. Moreover, WNV infection in hamsters causes reduced electromyography amplitudes of the gastrointestinal tract and diaphragm, and they have reduced heart rate variability (HRV), a read-out for the parasympathetic autonomic function. HRV was measured in both hamsters and mice using radiotelemetry to identify autonomic deficits. To identify areas of WNV infection within the medulla oblongata mapping to the dorsal motor nucleus of vagus (DMNV) and the nucleus ambiguus (NA), fluorogold dye was injected into the cervical trunk of the vagus nerve of hamsters. As a measurement of the loss of parasympathetic function, tachycardia was monitored contiguously over the time course of the disease. Decrease of HRV did not occur in all animals that died, which is not consistent with autonomic function being the mechanism of death. Fluorogold-stained cells in the DMNV were not stained for WNV envelope protein. Fourteen percent of WNV-stained cells were co-localized with fluorogold-stained cells in the NA. These data, however, did not suggest a fatal loss of autonomic functions because tachycardia was not observed in WNV-infected hamsters. Parasympathetic autonomic function deficit was not a likely mechanism of death in WNV-infected rodents and possibly in human patients with fatal WN neurological disease.

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.

The use of primary rat hepatocytes to achieve metabolic activation of promutagens in the Chinese hamster ovary/hypoxanthine-guanine phosphoribosyl transferase mutational assay.

PubMed

Bermudez, E; Couch, D B; Tillery, D

1982-01-01

A method is described in which primary rat hepatocytes have been cocultured with Chinese hamster ovary (CHO) cells to provide metabolic activation of promutagens in the Chinese hamster ovary/hypoxanthine-guanine phosphoribosyl transferase (CHO/HGPRT) mutational assay. Single cell hepatocyte suspensions were prepared from male Fischer-344 rats using the in situ collagenase perfusion technique. Hepatocytes were allowed to attach for 1.5 hours in tissue culture dishes containing an approximately equal number of CHO cells in log growth. The cocultures were exposed to promutagens for up to 20 hours in serum-free medium. The survival and 6-thioguanine-resistant fraction of treated CHO cells were then determined as in the standard CHO/HGPRT assay. Aflatoxin B1 (AFB1) 7,12-dimethylbenz(a)anthracene (DMBA) and benzo(a)pyrene (B(A)P) were found to produce increases in the mutant fractions of treated CHO cells as a function of concentration. The time required for optimum expression of the mutant phenotype following exposure to DMBA and AFB1 was approximately 8 days. Primary cell-mediated mutagenesis may be useful in elucidating metabolic pathways important in the production and detoxification of genotoxic products in vivo.

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

Zyflamend reduces LTB4 formation and prevents oral carcinogenesis in a 7,12-dimethylbenz[alpha]anthracene (DMBA)-induced hamster cheek pouch model.

PubMed

Yang, Peiying; Sun, Zheng; Chan, Diana; Cartwright, Carrie A; Vijjeswarapu, Mary; Ding, Jibin; Chen, Xiaoxin; Newman, Robert A

2008-11-01

Aberrant arachidonic acid metabolism, especially altered cyclooxygenase and 5-lipoxygenase (LOX) activities, has been associated with chronic inflammation as well as carcinogenesis in human oral cavity tissues. Here, we examined the effect of Zyflamend, a product containing 10 concentrated herbal extracts, on development of 7,12-dimethylbenz[alpha]anthracene (DMBA)-induced inflammation and oral squamous cell carcinoma (SCC). A hamster cheek pouch model was used in which 0.5% DMBA was applied topically onto the left cheek pouch of male Syrian golden hamsters either three times per week for 3 weeks (short term) or 6 weeks (long term). Zyflamend was then applied topically at one of three different doses (25, 50 and 100 microl) onto the left cheek pouch three times for 1 week (short-term study) or chronically for 18 weeks. Zyflamend significantly reduced infiltration of inflammatory cells, incidence of hyperplasia and dysplastic lesions, bromodeoxyuridine-labeling index as well as number of SCC in a concentration-dependent manner. Application of Zyflamend (100 microl) reduced formation of leukotriene B(4) (LTB(4)) by 50% compared with DMBA-treated tissues. The reduction of LTB(4) was concentration dependent. The effect of Zyflamend on inhibition of LTB(4) formation was further confirmed with in vitro cell-based assay. Adding LTB(4) to RBL-1 cells, a rat leukemia cell line expressing high levels of 5-LOX and LTA(4) hydrolase, partially blocked antiproliferative effect of Zyflamend. This study demonstrates that Zyflamend inhibited LTB(4) formation and modulated adverse histopathological changes in the DMBA-induced hamster cheek pouch model. The study suggests that Zyflamend might prevent oral carcinogenesis at the post-initiation stage.

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

[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.

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.

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.

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.

Changes in neocortical and hippocampal microglial cells during hibernation.

PubMed

León-Espinosa, Gonzalo; Regalado-Reyes, Mamen; DeFelipe, Javier; Muñoz, Alberto

2018-05-01

Mammalian hibernation proceeds alongside a wide range of complex brain adaptive changes that appear to protect the brain from extreme hypoxia and hypothermia. Using immunofluorescence, confocal microscopy, quantitative analysis methods and intracellular injections, we have characterized microglia morphological changes that occur in the neocortex and hippocampus of the Syrian hamster during hibernation. In euthermic hamsters, microglial cells showed the typical ramified/resting morphology with multiple long, thin and highly-branched processes homogeneously immunostained for Iba-1. However, during torpor, microglial cell process numbers increase significantly accompanied by a shortening of the Iba-1 immunoreactive processes, which show a fragmented appearance. Adaptative changes of microglial cells during torpor coursed with no expression of microglial cell activation markers. We discuss the possibility that these morphological changes may contribute to neuronal damage prevention during hibernation.

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.

Targeted transgene insertion into the CHO cell genome using Cre recombinase-incorporating integrase-defective retroviral vectors.

PubMed

Kawabe, Yoshinori; Shimomura, Takuya; Huang, Shuohao; Imanishi, Suguru; Ito, Akira; Kamihira, Masamichi

2016-07-01

Retroviral vectors have served as efficient gene delivery tools in various biotechnology fields. However, viral DNA is randomly inserted into the genome, which can cause problems, such as insertional mutagenesis and gene silencing. Previously, we reported a site-specific gene integration system, in which a transgene is integrated into a predetermined chromosomal locus of Chinese hamster ovary (CHO) cells using integrase-defective retroviral vectors (IDRVs) and Cre recombinase. In this system, a Cre expression plasmid is transfected into founder cells before retroviral transduction. In practical applications of site-specific gene modification such as for hard-to-transfect cells or for in vivo gene delivery, both the transgene and the Cre protein into retroviral virions should be encapsulate. Here, we generated novel hybrid IDRVs in which viral genome and enzymatically active Cre can be delivered (Cre-IDRVs). Cre-IDRVs encoding marker genes, neomycin resistance and enhanced green fluorescent protein (EGFP), flanked by wild-type and mutated loxP sites were produced using an expression plasmid for a chimeric protein of Cre and retroviral gag-pol. After analyzing the incorporation of the Cre protein into retroviral virions by Western blotting, the Cre-IDRV was infected into founder CHO cells, in which marker genes (hygromycin resistance and red fluorescent protein) flanked with corresponding loxP sites are introduced into the genome. G418-resistant colonies expressing GFP appeared and the site-specific integration of the transgene into the expected chromosomal site was confirmed by PCR and sequencing of amplicons. Moreover, when Cre-IDRV carried a gene expression unit for a recombinant antibody, the recombinant cells in which the antibody expression cassette was integrated in a site-specific manner were generated and the cells produced the recombinant antibody. This method may provide a promising tool to perform site-specific gene modification according to Cre-based cell engineering. Biotechnol. Bioeng. 2016;113: 1600-1610. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

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.

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.

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.

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

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 suggest that differences among rodent species in pleural responses to inhaled fibers are due to a delivered dose of fibers and to the biological responses to the presence of the fibers.

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

Pharmacokinetics of meso-(tetrahydroxyphenyl)chlorin (m-THPC) studied by fluorescence spectroscopy on early cancer of the cheek pouch mucosa of Golden Syrian hamsters

NASA Astrophysics Data System (ADS)

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

1995-01-01

Golden Syrian hamsters are evaluated as an animal model for phototherapy of early squamous cell carcinomas of the mucosa of the upper aerodigestive tract, the esophagus and the tracheobronchial 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). The same drug is currently in phase I, II clinical trials for ENT patients with superficial squamous cell carcinomas. By means of light induced fluorescence (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 by 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 tests of a number of PDT variables of new photosensitizers preceding their clinical application as well as for optimization of the multiple parameters of clinical phototherapy.

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 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.

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.

[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 Ratio

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.

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.

Circadian time-dependent chemopreventive potential of withaferin-A in 7,12-dimethylbenz[a]anthracene-induced oral carcinogenesis.

PubMed

Manoharan, Shanmugam; Panjamurthy, Kuppusamy; Balakrishnan, Subramanian; Vasudevan, Kalaiarasan; Vellaichamy, Lakshmanan

2009-01-01

Circadian time-dependent treatment with chemotherapeutic drugs (chronotherapy) optimizes the therapeutic index by maximizing treatment efficacy and minimizing toxicity. The circadian time-dependent chemopreventive and anti-lipid peroxidative efficacy of withaferin-A in 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinogenesis was investigated in the present study. We induced oral squamous cell carcinoma in the buccal pouches of golden Syrian hamsters during the day (4:00, 8:00, 12:00, 16:00, 20:00 and 24:00) by application of DMBA three times per week for 14 weeks. The circadian time-dependent tumor incidence, volume and burden were observed in hamsters treated with either DMBA alone or DMBA + withaferin-A. The circadian pattern of lipid peroxidation by-products, as measured by the formation of thiobarbituric acid reactive substances (TBARS) and enzymatic antioxidants [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)], was also analyzed in the buccal mucosa of DMBA-treated hamsters. We found the highest incidence of tumor formation at 24.00 h in hamsters treated with DMBA alone as compared to other experimental groups. Circadian dysregulation of lipid peroxidation and antioxidant status was observed in DMBA-treated animals as compared to control animals. Oral (po) administration of withaferin-A (20 mg/kg) completely prevented the formation of tumors between 8.00 h and 12.00 h and synchronized the status of lipid peroxidation and antioxidants in the buccal mucosa of hamsters treated with DMBA alone. Also, oral administration of withaferin-A to DMBA-treated animals significantly reduced the formation of tumors and synchronized the status of lipid peroxidation and antioxidants in the rest of the time intervals. Our study thus suggests that withaferin-A has significant chemopreventive and anti-lipid peroxidative potential in DMBA-induced oral carcinogenesis, probably by interfering with DMBA-induced abnormal cell proliferation in the buccal mucosa.

Two-photon autofluorescence spectroscopy of oral mucosa tissue

NASA Astrophysics Data System (ADS)

Edward, Kert; Shilagard, Tuya; Qiu, Suimin; Vargas, Gracie

2011-03-01

The survival rate for individuals diagnosed with oral cancer is correlated with the stage of detection. Thus the development of novel techniques for the earliest possible detection of malignancies is of critical importance. Single photon (1P) autofluorescence spectroscopy has proven to be a powerful diagnostic tool in this regard, but 2P (two photon) spectroscopy remains essentially unexplored. In this investigation, a spectroscopic system was incorporated into a custom-built 2P laser scanning microscope. Oral cancer was induced in the buccal pouch of Syrian Golden hamsters by tri-weekly topical application of 9,10-dimethyl-1,2-benzanthracene (DMBA).Three separated sites where investigated in each hamster at four excitation wavelengths from 780 nm to 890 nm. A Total of 8 hamsters were investigated (4 normal and 4 DMBA treated). All investigated sites were imaged via 2p imaging, marked for biopsy, processed for histology and H&E staining, and graded by a pathologist. The in vivo emission spectrum for normal, mild/high grade dysplasia and squamous cell carcinoma is presented. It is shown that the hamsters with various stages of dysplasia are characterized by spectral differences as a function of depth and excitation wavelength, compared to normal hamsters.

Effect of mangrove black tea extract from Ceriops decandra (Griff.) on hematology and biochemical changes in dimethyl benz[a]anthracene-induced hamster buccal pouch carcinogenesis.

PubMed

Sithranga Boopathy, N; Kathiresan, K; Jeon, Y J

2011-09-01

Effect of the black tea extracted from a mangrove plant species, Ceriops decandra (Griff.) was studied on dimethyl benz[a]anthracene (DMBA)-induced changes in blood hematology and plasma non-enzymatic antioxidants in male hamsters. Hamsters were painted with 0.5% solution of DMBA in liquid paraffin on the right buccal pouch three times in a week up to 14 weeks. Each application treated with 0.4mg of DMBA. The mangrove black tea extract (MBTE) was administrated orally with 5mgkg(-1) twice a day and then with DMBA on alternate days. Results showed that the DMBA caused a significant (P<0.05) decline in the levels of reduced glutathione (GSH), vitamin-C, -E, red blood cells, hemoglobin, mean corpuscular volume and hematocrit; and increase in the levels of WBC, platelets, lymphocytes and neutrophils. The MBTE prevented the DMBA-induced adverse changes significantly in blood and biochemical parameters of the male hamsters. This work concluded that the black tea extracted from the coastal mangrove species C. decandra prevented the DMBA-induced buccal pouch carcinogenesis in hamsters. Copyright © 2011 Elsevier B.V. All rights reserved.

Control of carbohydrate processing: increased beta-1,6 branching in N-linked carbohydrates of Lec9 CHO mutants appears to arise from a defect in oligosaccharide-dolichol biosynthesis.

PubMed Central

Rosenwald, A G; Stanley, P; Krag, S S

1989-01-01

A correlation between increased beta-1,6 branching of N-linked carbohydrates and the ability of a cell to metastasize or to form a tumor has been observed in several experimental models. Lec9 Chinese hamster ovary (CHO) mutants exhibit a drastic reduction in tumorigenicity in nude mice, and this phenotype directly correlates with their ability to attach an increased proportion of beta-1,6-branched carbohydrates to the G glycoprotein of vesicular stomatitis virus (J. Ripka, S. Shin, and P. Stanley, Mol. Cell. Biol. 6:1268-1275, 1986). In this paper we provide evidence that cellular carbohydrates from Lec9 cells also contain an increased proportion of beta-1,6-branched carbohydrates, although they do not possess significantly increased activity of the beta-1,6 branching enzyme (GlcNAc-transferase V). Biosynthetic labeling experiments show that a substantial degree of underglycosylation occurs in Lec9 cells and that this affects several classes of glycoproteins. Lec9 cells synthesize ca. 40-fold less Glc3Man9GlcNAc2-P-P-lipid and ca. 2-fold less Man5GlcNAc2-P-P-lipid than parental cells do. In addition, Lec9 cells possess ca. fivefold less protein-bound oligosaccharide intermediates, and one major species is resistant to release by endo-beta-N-acetylglucosaminidase H (endo H). Membranes of Lec9 cells exhibit normal mannosylphosphoryldolichol synthase, glucosylphosphoryldolichol synthase, and N-acetylglucosaminylphosphate transferase activities in the presence of exogenous dolichyl phosphate. However, in the absence of exogenous dolichyl phosphate, mannosylphosphoryldolichol synthase and glucosylphosphoryldolichol synthase activities are reduced in membranes of Lec9 cells, indicating that membranes of Lec9 cells are deficient in lipid phosphate. This was confirmed by analysis of lipids labeled by [3H]mevalonate, which showed that Lec9 cells have less lipid phosphate than parental CHO cells. Mechanisms by which a defect in the synthesis of dolichol-oligosaccharides might alter the degree of beta-1,6 branching in N-linked carbohydrates are discussed. Images PMID:2725506

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

Infection of the upper respiratory tract of hamsters by the bovine parainfluenza virus type 3 BN-1 strain expressing enhanced green fluorescent protein.

PubMed

Ohkura, Takashi; Minakuchi, Moeko; Sagai, Mami; Kokuho, Takehiro; Konishi, Misako; Kameyama, Ken-Ichiro; Takeuchi, Kaoru

2015-02-01

Bovine parainfluenza virus type 3 (BPIV3) is an important pathogen associated with bovine respiratory disease complex (BRDC). We have generated a recombinant BPIV3 expressing enhanced green fluorescent protein (rBPIV3-EGFP) based on the BN-1 strain isolated in Japan. After intranasal infection of hamsters with rBPIV3-EGFP, EGFP fluorescence was detected in the upper respiratory tract including the nasal turbinates, pharynx, larynx, and trachea. In the nasal turbinates, rBPIV3-EGFP attained high titers (>10(6) TCID50/g of tissue) 2-4 days after infection. Ciliated epithelial cells in the nasal turbinates and trachea were infected with rBPIV3-EGFP. Histopathological analysis indicated that mucosal epithelial cells in bronchi were shed by 6 days after infection, leaving non-ciliated cells, which may have increased susceptibility to bacterial infection leading to the development of BRDC. These data indicate that rBPIV3-EGFP infection of hamsters is a useful small animal model for studying the development of BPIV3-associated BRDC. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

Acanthamoeba culbertsoni isolated from a clinical case with intraocular dissemination: Structure and in vitro analysis of the interaction with hamster cornea and MDCK epithelial cell monolayers.

PubMed

González-Robles, Arturo; Omaña-Molina, Maritza; Salazar-Villatoro, Lizbeth; Flores-Maldonado, Catalina; Lorenzo-Morales, Jacob; Reyes-Batlle, María; Arnalich-Montiel, Francisco; Martínez-Palomo, Adolfo

2017-12-01

Acanthamoeba culbertsoni trophozoites, previously isolated from a human keratitis case with severe intraocular damage, were maintained in axenic culture. Co-incubation of amoebae with MDCK cell monolayers demonstrated an apparent preference of the amoebae to introduce themselves between the cells. The trophozoites appeared to cross the cell monolayer through the tight junctions, which resulted in decreased trans-epithelial resistance (TER) measurements. Unexpectedly, after co-incubation of amoebae with hamster corneas, we observed that the trophozoites were able to cross the different cell layers and reach the corneal stroma after only 12 h of interaction, in contrast to other Acanthamoeba species. These observations suggest that this A. culbertsoni isolate is particularly pathogenic. Further research with diverse methodologies needs to be performed to explain the unique behavior of this Acanthamoeba strain. Copyright © 2017 Elsevier Inc. All rights reserved.

Study of radiation effects on mammalian cells in vitro

NASA Technical Reports Server (NTRS)

Sinclair, W. K.

1968-01-01

Radiation effect on single cells and cell populations of Chinese hamster lung tissue is studied in vitro. The rate and position as the cell progresses through the generation cycle shows division delay, changes in some biochemical processes in the cell, chromosomal changes, colony size changes, and loss of reproductive capacity.

Response to high LET radiation 12C (LET, 295 keV/microm) in M5 cells, a radio resistant cell strain derived from Chinese hamster V79 cells.

PubMed

Pathak, R; Sarma, A; Sengupta, B; Dey, S K; Khuda-Bukhsh, A R

2007-01-01

To study the effects of 12C-beam of 295 keV/microm (57.24 MeV) on M5 and Chinese hamster V79 cells by using cytogenetic assays like micronuclei (MN) induction, chromosomal aberrations (CA) and apoptosis. Additionally, the relative survival of these two cell lines was tested by the colony forming ability of the cells, with a view to understanding the mechanism of cellular damages that lead to difference in cell survival. Confluent cells were irradiated with 12C-beam at various doses using 15UD Pelletron accelerator. Cell survival was studied by the colony forming ability of cells. MN assay was done by fluorescent staining. Different types of chromosomal aberrations in metaphase cells were scored at 12 h after irradiation. Apoptosis was measured at different post irradiation times as detected by nuclear fragmentation and DNA ladder was prepared after 48 h of incubation. Dose-dependent decrease in surviving fractions was found in both the cell lines. However, the surviving fractions were higher in M5 cells in comparison to V79 cells when exposed to the same radiation doses. On the other hand, induced MN frequencies, CA frequencies and apoptosis percentages were less in M5 cells than V79 cells. Very good correlations between surviving fractions and induced MN frequencies or induced total CA or induced apoptosis percentages were obtained in this study. The cell strain M5 showed relatively more radio-resistance to 12C-beam compared to Chinese hamster V79 cells in this study. As the MN formation, CA and apoptosis induction were less in M5 cells as compared to parental V79 cells, the higher cell survival in the former could possibly be attributed to their better repairing ability leading to higher cell survival.

Social reward: interactions with social status, social communication, aggression, and associated neural activation in the ventral tegmental area.

PubMed

Gil, Mario; Nguyen, Ngoc-Thao; McDonald, Mark; Albers, H Elliott

2013-07-01

Nearly all species engage in a variety of intraspecific social interactions, and there is evidence that these interactions are rewarding. Less is known, however, about the factors that influence social reward. Using the conditioned place preference paradigm, we tested whether social interactions are rewarding for male Syrian hamsters. We also tested whether social stimuli increase neural activation in the ventral tegmental area (VTA), a component of the mesolimbic reward system, and how individual differences in social behavior and experience influence neural activation. In the present study, we found that hamsters developed a conditioned place preference for social interactions, but the effects were significantly stronger in dominant animals compared with subordinates. The number of Fos-immunoreactive cells in the VTA was significantly higher in hamsters that had engaged in a direct social encounter compared with hamsters exposed to a caged stimulus hamster or controls. Interestingly, socially experienced males had more Fos-immunoreactive cells in the VTA than socially naive males after exposure to a social stimulus. Surprisingly, the amount of Fos immunoreactivity in the VTA induced by a social stimulus was correlated with the amount of aggressive/dominance behaviors that had been observed during interactions that had occurred 2 months earlier. Our results indicate that social interactions between males are rewarding, and that social dominance increases the reward value. Social interactions stimulate the mesolimbic reward system, and social experience enhances its response to novel social stimuli and may produce long-term changes in the neural mechanisms that mediate the maintenance of dominance over long periods of time. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

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.

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

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.

Assessment of prion reduction filters in decreasing infectivity of ultracentrifuged 263K scrapie-infected brain homogenates in "spiked" human blood and red blood cells.

PubMed

Cardone, Franco; Sowemimo-Coker, Samuel; Abdel-Haq, Hanin; Sbriccoli, Marco; Graziano, Silvia; Valanzano, Angelina; Berardi, Vito Angelo; Galeno, Roberta; Puopolo, Maria; Pocchiari, Maurizio

2014-04-01

The safety of red blood cells (RBCs) is of concern because of the occurrence of four transfusion-transmitted variant Creutzfeldt-Jakob disease (vCJD) cases in the United Kingdom. The absence of validated screening tests requires the use of procedures to remove prions from blood to minimize the risk of transmission. These procedures must be validated using infectious prions in a form that is as close as possible to one in blood. Units of human whole blood (WB) and RBCs were spiked with high-speed supernatants of 263K scrapie-infected hamster brain homogenates. Spiked samples were leukoreduced and then passed through prion-removing filters (Pall Corporation). In another experiment, RBCs from 263K scrapie-infected hamsters were treated as above, and residual infectivity was measured by bioassay. The overall removal of infectivity by the filters from prion-spiked WB and RBCs was approximately two orders of magnitude. No infectivity was detected in filtered hamster RBCs endogenously infected with scrapie. The use of prion-removing filters may help to reduce the risk of transfusion-transmitted vCJD. To avoid overestimation of prion removal efficiency in validation studies, it may be more appropriate to use supernates from ultracentrifugation of scrapie-infected hamster brain homogenate rather than the current standard brain homogenates. © 2013 American Association of Blood Banks.

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

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.

Biophysical studies on calcium and carbohydrate binding to carbohydrate recognition domain of Gal/GalNAc lectin from Entamoeba histolytica: insights into host cell adhesion.

PubMed

Yadav, Rupali; Verma, Kuldeep; Chandra, Mintu; Mukherjee, Madhumita; Datta, Sunando

2016-09-01

Entamoeba histolytica, an enteric parasite expresses a Gal/GalNAc-specific lectin that contributes to its virulence by establishing adhesion to host cell. In this study, carbohydrate recognition domain of Hgl (EhCRD) was purified and biophysical studies were conducted to understand the thermodynamic basis of its binding to carbohydrate and Ca(++) Here, we show that carbohydrate recognition domain (CRD) of the lectin binds to calcium through DPN motif. To decipher the role of calcium in carbohydrate binding and host cell adhesion, biophysical and cell-based studies were carried out. We demonstrated that the presence of the cation neither change the affinity of the lectin for carbohydrates nor alters its conformation. Mutation of the calcium-binding motif in EhCRD resulted in complete loss of ability to bind calcium but retained its affinity for carbohydrates. Purified EhCRD significantly diminished adhesion of the amebic trophozoites to Chinese Hamster Ovary (CHO) cells as well as triggered red blood cell agglutination. The calcium-binding defective mutant abrogated amebic adhesion to CHO cells similar to the wild-type protein, but it failed to agglutinate RBCs suggesting a differential role of the cation in these two processes. This study provides the first molecular description of the role of calcium in Gal/GalNAc mediated host cell adhesion. © The Authors 2016. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Mechanism of proteasomal degradation of inositol trisphosphate receptors in CHO-K1 cells.

PubMed

Bhanumathy, Cunnigaiper D; Nakao, Steven K; Joseph, Suresh K

2006-02-10

myo-Inositol 1,4,5-trisphosphate receptor (IP3R) degradation occurs in response to carbachol (Cch) stimulation of CHO-K1 cells. The response was mediated by endogenous muscarinic receptors and was blocked by atropine or proteasomal inhibitors. We have used these cells to identify the sites of ubiquitination on IP3Rs and study the role of Ca2+ and substrate recognition properties of the degradation system using exogenously expressed IP3R constructs. Employing caspase-3 for IP3R cleavage, we show that Cch promotes polyubiquitination in the N-terminal domain and monoubiquitination in the C-terminal domain. The addition of extracellular Ca2+ to Ca2+-depleted Chinese hamster ovary (CHO) cells initiates IP3R degradation provided Cch is present. This effect is inhibited by thapsigargin. The data suggest that both a sustained elevation of IP3 and a minimal content of Ca2+ in the endoplasmic reticulum lumen is required to initiate IP3R degradation. Transient transfection of IP3R constructs into CHO cells indicated the selective degradation of only the SI+ splice variant of the type I IP3R. This was also the splice form present endogenously in these cells. A pore-defective, nonfunctional SI+ IP3R mutant (D2550A) was also degraded in Cch-stimulated cells. The Cch-mediated response in CHO cells provides a convenient model system to further analyze the Ca2+ dependence and structural requirements of the IP3R proteasomal degradation pathway.

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 even in tissues for which a significant difference in leptospiral load was not observed. In addition, our results suggest a serovar Manilae-specific mechanism responsible for inducing severe damage in kidneys and hemorrhage in lung.

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 even in tissues for which a significant difference in leptospiral load was not observed. In addition, our results suggest a serovar Manilae-specific mechanism responsible for inducing severe damage in kidneys and hemorrhage in lung. PMID:26146835

Entamoeba histolytica. Phagocytosis as a virulence factor

PubMed Central

1983-01-01

In this paper, we attempted to define the role of phagocytosis in the virulence of Entamoeba histolytica. We have isolated, from a highly phagocytic and virulent strain, a clone deficient in phagocytosis. Trophozoites of wild-type strain HM1:IMSS were fed with Escherichia coli strain CR34-Thy- grown on 5-bromo,2'-deoxyuridine. The trophozoites that had incorporated the base analog through phagocytosis of the bacteria were killed by irradiation with 310 nm light. The survivors, presumably trophozoites defective in phagocytosis, were grown until log phase and submitted two more times to the selection procedure. Clone L-6, isolated from a subpopulation resulting from this selection procedure, showed 75-85% less erythrophagocytic activity than the wild-type strain. The virulence of clone L-6 and strain HM1:IMSS was measured. The inoculum required to induce liver abscesses in 50% of the newborn hamsters inoculated (AD50) of HM1:IMSS was 1.5 X 10(4) trophozoites. Clone L-6 trophozoites failed to induce liver abscesses in newborn hamsters even with inocula of 5 X 10(5) trophozoites. Virulence revertants were obtained by successive passage of L-6 trophozoites through the liver of young hamsters. The trophozoites that recovered the ability to produce liver abscesses simultaneously recuperate high erythrophagocytic rates. These results show that phagocytosis is involved in the aggressive mechanisms of E. histolytica. PMID:6313842

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.

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 genotoxic and cytotoxic properties of pesticides employed in Italian agricultural practices.

PubMed

De Marco, A; De Salvia, R; Polani, S; Ricordy, R; Sorrenti, F; Perticone, P; Cozzi, R; D'Ambrosio, C; De Simone, C; Guidotti, M; Albanesi, T; Duranti, G; Festa, F; Gensabella, G; Owczarek, M

2000-07-01

In a program coordinated by the Italian Ministry of Works, we tested in vitro four pesticides widely employed in a developed agricultural region of central Italy. The four commercial agents were chosen on the basis of their diffusion in agricultural practice, knowledge of their active principle(s), and scant availability of data concerning their toxic and genotoxic activity. The agents were Cirtoxin, Decis, Tramat Combi (TC), and Lasso Micromix (LM). All substances were tested in three in vitro systems: Chinese hamster ovary (CHO) cells, a metabolically competent hamster cell line (Chinese hamster epithelial liver; CHEL), and root tips of Vicia faba (VF). The cytotoxic and genotoxic end points challenged were micronuclei and root tip length (RTL) in VF and mitotic index (MI), proliferation index (PI), cell survival (CS), cell growth (CG), cell cycle length (CCL), sister chromatid exchanges, chromosomal aberrations, and single-cell gel electrophoresis, or comet assay, in CHEL and CHO cells. Tested doses ranged from the field dose up to 200x the field dose to take into account accumulation effects. On the whole, tested agents appear to induce genotoxic damage only at subtoxic or toxic doses, indicating a low clastogenic risk. MI, PI, CS, CG, RTL, and CCL appear to be the less sensitive end points, showing no effects in the presence of a clear positive response in some or all of the other tests. Using cytogenetic tests, we obtained positive results for TC and LM treatments in CHO but not in CHEL cells. These data could be accounted for by postulating a detoxifying activity exerted by this cell line. However, cytogenetic end points appear to be more sensitive than those referring to cytotoxicity.

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

cDNA cloning of the human monocarboxylate transporter 1 and chromosomal localization of the SLC16A1 locus to 1p13.2-p12

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

Garcia, C.K.; Li, X.; Luna, J.

1994-09-15

Lactate and pyruvate are transported across cell membranes by monocarboxylate transporters (MCTs). Here, the authors use the recently cloned cDNA for hamster MCT1 to isolate cDNA and genomic clones for human MCT1. Comparison of the human and hamster amino acid sequences revealed that the proteins are 86% identical. The gene for human MCT1 (gene symbol, SLC16A1) was localized to human chromosome bands 1p13.2-p12 by PCR analysis of panels of human X rodent cell hybrid lines and by fluorescence chromosomal in situ hybridization. 9 refs., 2 figs.

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 administration. PMID:9317039

Molecular Genetic Analysis of an Endotoxin Nonresponder Mutant Cell Line

PubMed Central

Schromm, Andra B.; Lien, Egil; Henneke, Philipp; Chow, Jesse C.; Yoshimura, Atsutoshi; Heine, Holger; Latz, Eicke; Monks, Brian G.; Schwartz, David A.; Miyake, Kensuke; Golenbock, Douglas T.

2001-01-01

Somatic cell mutagenesis is a powerful tool for characterizing receptor systems. We reported previously two complementation groups of mutant cell lines derived from CD14-transfected Chinese hamster ovary–K1 fibroblasts defective in responses to bacterial endotoxin. Both classes of mutants expressed a normal gene product for Toll-like receptor (TLR)4, and fully responded to stimulation by tumor necrosis factor (TNF)-α or interleukin (IL)-1β. We identified the lesion in one of the complementation groups in the gene for MD-2, a putative TLR4 coreceptor. The nonresponder phenotype of this mutant was reversed by transfection with MD-2. Cloning of MD-2 from the nonresponder cell line revealed a point mutation in a highly conserved region resulting in a C95Y amino acid exchange. Both forms of MD-2 colocalized with TLR4 on the cell surface after transfection, but only the wild-type cDNA reverted the lipopolysaccharide (LPS) nonresponder phenotype. Furthermore, soluble MD-2, but not soluble MD-2C95Y, functioned to enable LPS responses in cells that expressed TLR4. Thus, MD-2 is a required component of the LPS signaling complex and can function as a soluble receptor for cells that do not otherwise express it. We hypothesize that MD-2 conformationally affects the extracellular domain of TLR4, perhaps resulting in a change in affinity for LPS or functioning as a portion of the true ligand for TLR4. PMID:11435474

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

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

Effect of caffeine on the ultraviolet light induction of SV40 virus from transformed hamster cells

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

Zamansky, G.B.; Kleinman, L.F.; Little, J.B.

1976-01-01

The effect of caffeine on the uv light induction of SV40 virus from two transformed hamster cell lines heterogeneous for the induction of infectious virus was studied. The amount of virus induced was significantly increased in both cell lines when exposure to uv light was followed by treatment with caffeine. Caffeine in the absence of uv irradiation did not stimulate virus induction, nor did it stimulate SV40 replication in a lytic infection. There was an apparent difference in the concentrations of caffeine which maximally stimulated SV40 virus induction in the two cell lines. This effect could not be explained bymore » differences in cell survival after exposure to uv light and caffeine. Since caffeine is known to cause the accumulation of gaps formed in DNA during postreplication repair of uv-irradiated rodent cells, our results support the hypothesis that the formation of gaps or breaks in DNA is an important early step in virus induction.« less

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

Induction of morphological transformation in mouse C3H/10T1/2 clone 8 cells and chromosomal damage in hamster A(T1)C1-3 cells by cancer chemotherapeutic agents.

PubMed

Benedict, W F; Banerjee, A; Gardner, A; Jones, P A

1977-07-01

Various cancer chemotherapeutic agents including alkylating agents, antimetabolites, and antibiotics or natural products were studied for their ability to produce morphological transformation in the C3H/10T1/2 clone 8 mouse cell line and chromosomal damage in the A(T1)C1-3 hamster cell line following a 24-hr exposure of each agent at different concentrations. Those drugs that were known to be carcinogenic in vivo also produced morphological transformation and chromosomal damage, whereas those agents that have not been shown to be carcinogenic in vivo produced neither transformation nor chromosomal lesions. The concentrations used for these studies were in general similar to those actually reached in the plasma of patients treated with these same drugs for malignant, as well as certain nonmalignant, conditions.

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.

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.

Locomotive forces produced by single leukocytes in vivo and in vitro.

PubMed

Guilford, W H; Lantz, R C; Gore, R W

1995-05-01

We report here the first time-resolved measurements of the forces produced during the migration of single leukocytes in vivo and in vitro. Pulmonary macrophages from hamsters and mice, in vitro, and Nembutal (pentobarbital sodium)-anesthetized hamster neutrophils, in vivo, generated maximum locomotive forces ranging from 1.9 to 10.7 nN or tenths of microdynes. Force production was periodic and correlated with the length of the leading lamellipod but not with generalized cell ruffling. Although the extension of the leading lamella is critical to locomotive force generation, these direct measurements suggest that lamellar extension may not arise from the same contractile processes driving forward motion of the cell mass. Indeed, cell ruffling, lamellar extension, and locomotive force generation may be differentially controlled and have different origins. This technique may be extended to test numerous hypotheses of how these and other nonmuscle cells crawl.

Analysis of yeast prp20 mutations and functional complementation by the human homologue RCC1, a protein involved in the control of chromosome condensation.

PubMed

Fleischmann, M; Clark, M W; Forrester, W; Wickens, M; Nishimoto, T; Aebi, M

1991-07-01

Mutations in the PRP20 gene of yeast show a pleiotropic phenotype, in which both mRNA metabolism and nuclear structure are affected. srm1 mutants, defective in the same gene, influence the signal transduction pathway for the pheromone response. The yeast PRP20/SRM1 protein is highly homologous to the RCC1 protein of man, hamster and frog. In mammalian cells, this protein is a negative regulator for initiation of chromosome condensation. We report the analysis of two, independently isolated, recessive temperature-sensitive prp20 mutants. They have identical G to A transitions, leading to the alteration of a highly conserved glycine residue to glutamic acid. By immunofluorescence microscopy the PRP20 protein was localized in the nucleus. Expression of the RCC1 protein can complement the temperature-sensitive phenotype of prp20 mutants, demonstrating the functional similarity of the yeast and mammalian proteins.

Evaluation of the chemopreventive response of naringenin-loaded nanoparticles in experimental oral carcinogenesis using laser-induced autofluorescence spectroscopy

NASA Astrophysics Data System (ADS)

Sulfikkarali, N. K.; Krishnakumar, N.

2013-04-01

The aim of the present study is to investigate the chemopreventive effects of prepared naringenin-loaded nanoparticles (NARNPs) relative to the efficacy of free naringenin (NAR) in modifying the carcinogenic process and to study the changes in the endogenous fluorophores during DMBA-induced hamster buccal pouch (HBP) carcinogenesis by laser-induced autofluorescence (LIAF) spectroscopy. LIAF emission spectra from the hamster buccal mucosa of the control and experimental groups of animals were recorded in the 350-700 nm spectral range on a miniature fiber optic spectrometer from different anatomical sites of each group, with excitation at 404 nm from a diode laser. Oral squamous cell carcinoma (OSCC) was developed in the buccal pouch of golden Syrian hamsters by painting with 0.5% DMBA in liquid paraffin three times a week for 14 weeks. DMBA-painted animals revealed morphological changes, hyperplasia, dysplasia and well-differentiated squamous cell carcinoma. LIAF emission spectra showed significant difference between the control and tumor tissues. The tumor tissues are characterized by an increase in the emission of porphyrins and a decrease in the emission of nicotinamide adenine dinucleotide hydrogenase (NADH) and flavin adenine nucleotide (FAD) when compared to the control tissues. Furthermore, oral administration of NAR and its nanoparticulates restored the status of endogenous fluorophores in the buccal mucosa of DMBA-painted animals. On a comparative basis, the treatment of nanoparticulate naringenin was found to be more effective than free naringenin in completely preventing the formation of squamous cell carcinoma and in improving the status of endogenous porphyrins to a normal range in DMBA-induced hamster buccal pouch carcinogenesis. The result of the present study further suggests that LIAF spectroscopy may be a very valuable tool for rapid and sensitive detection of endogenous fluorophore changes in response to chemopreventive agents.

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.

A Consistent Orally-Infected Hamster Model for Enterovirus A71 Encephalomyelitis Demonstrates Squamous Lesions in the Paws, Skin and Oral Cavity Reminiscent of Hand-Foot-and-Mouth Disease.

PubMed

Phyu, Win Kyaw; Ong, Kien Chai; Wong, Kum Thong

2016-01-01

Enterovirus A71 (EV-A71) causes self-limiting, hand-foot-and-mouth disease (HFMD) that may rarely be complicated by encephalomyelitis. Person-to-person transmission is usually by fecal-oral or oral-oral routes. To study viral replication sites in the oral cavity and other tissues, and to gain further insights into virus shedding and neuropathogenesis, we developed a consistent, orally-infected, 2-week-old hamster model of HFMD and EV-A71 encephalomyelitis. Tissues from orally-infected, 2-week-old hamsters were studied by light microscopy, immunohistochemistry and in situ hybridization to detect viral antigens and RNA, respectively, and by virus titration. Hamsters developed the disease and died after 4-8 days post infection; LD50 was 25 CCID50. Macroscopic cutaneous lesions around the oral cavity and paws were observed. Squamous epithelium in the lip, oral cavity, paw, skin, and esophagus, showed multiple small inflammatory foci around squamous cells that demonstrated viral antigens/RNA. Neurons (brainstem, spinal cord, sensory ganglia), acinar cells (salivary gland, lacrimal gland), lymphoid cells (lymph node, spleen), and muscle fibres (skeletal, cardiac and smooth muscles), liver and gastric epithelium also showed varying amounts of viral antigens/RNA. Intestinal epithelium, Peyer's patches, thymus, pancreas, lung and kidney were negative. Virus was isolated from oral washes, feces, brain, spinal cord, skeletal muscle, serum, and other tissues. Our animal model should be useful to study squamous epitheliotropism, neuropathogenesis, oral/fecal shedding in EV-A71 infection, person-to-person transmission, and to test anti-viral drugs and vaccines.

A Consistent Orally-Infected Hamster Model for Enterovirus A71 Encephalomyelitis Demonstrates Squamous Lesions in the Paws, Skin and Oral Cavity Reminiscent of Hand-Foot-and-Mouth Disease

PubMed Central

Phyu, Win Kyaw; Ong, Kien Chai; Wong, Kum Thong

2016-01-01

Enterovirus A71 (EV-A71) causes self-limiting, hand-foot-and-mouth disease (HFMD) that may rarely be complicated by encephalomyelitis. Person-to-person transmission is usually by fecal-oral or oral-oral routes. To study viral replication sites in the oral cavity and other tissues, and to gain further insights into virus shedding and neuropathogenesis, we developed a consistent, orally-infected, 2-week-old hamster model of HFMD and EV-A71 encephalomyelitis. Tissues from orally-infected, 2-week-old hamsters were studied by light microscopy, immunohistochemistry and in situ hybridization to detect viral antigens and RNA, respectively, and by virus titration. Hamsters developed the disease and died after 4–8 days post infection; LD50 was 25 CCID50. Macroscopic cutaneous lesions around the oral cavity and paws were observed. Squamous epithelium in the lip, oral cavity, paw, skin, and esophagus, showed multiple small inflammatory foci around squamous cells that demonstrated viral antigens/RNA. Neurons (brainstem, spinal cord, sensory ganglia), acinar cells (salivary gland, lacrimal gland), lymphoid cells (lymph node, spleen), and muscle fibres (skeletal, cardiac and smooth muscles), liver and gastric epithelium also showed varying amounts of viral antigens/RNA. Intestinal epithelium, Peyer’s patches, thymus, pancreas, lung and kidney were negative. Virus was isolated from oral washes, feces, brain, spinal cord, skeletal muscle, serum, and other tissues. Our animal model should be useful to study squamous epitheliotropism, neuropathogenesis, oral/fecal shedding in EV-A71 infection, person-to-person transmission, and to test anti-viral drugs and vaccines. PMID:26815859

Animal cells dependent on exogenous phosphatidylcholine for membrane biogenesis.

PubMed Central

Esko, J D; Nishijima, M; Raetz, C R

1982-01-01

A Chinese hamster ovary cell (CHO) mutant (strain 58), defective in CDP-choline synthetase (cholinephosphate cytidylyltransferase; CTP:cholinephosphate cytidylyltransferase, EC 2.7.7.15), is temperature sensitive for growth and contains less than half of the normal amount of phosphatidylcholine under nonpermissive conditions [Esko, J. D. & Raetz, C. R. H. (1980) Proc. Natl. Acad. Sci. USA 77, 5192-5196]. We now report that the addition of 40 microM egg phosphatidylcholine or lysophosphatidylcholine to the medium suppresses the temperature sensitivity of mutant 58 and permits the growth of colonies at the restrictive temperature. Phospholipids with different polar headgroups, lipoprotein-bound phospholipids, sphingomyelin, and glycerophosphocholine do not support prolonged growth at 40 degrees C, whereas phosphatidylcholine analogs such as phosphatidyldimethylethanolamine, D-phosphatidylcholine, and beta-phosphatidylcholine are quite effective. A broad range of saturated phosphatidylcholines, especially those with fatty acids 12-18 carbons in length, suppresses the phenotype. Phospholipids containing ether-linked hydrocarbons are ineffective, whereas polyunsaturated phosphatidylcholines are toxic. Residual endogenous synthesis of phosphatidylcholine by the mutant is not stimulated under conditions of phenotypic bypass, but the uptake of exogenous lipid is enhanced considerably compared to the wild type. Our findings demonstrate that exogenous phospholipid can provide at least 50% of the phosphatidylcholine required for membrane biogenesis in animal cells and that uptake of exogenous phospholipids may be regulated. PMID:6281780

FANCJ helicase controls the balance between short- and long-tract gene conversions between sister chromatids

PubMed Central

Nath, Sarmi; Somyajit, Kumar; Mishra, Anup; Scully, Ralph

2017-01-01

Abstract The FANCJ DNA helicase is linked to hereditary breast and ovarian cancers as well as bone marrow failure disorder Fanconi anemia (FA). Although FANCJ has been implicated in the repair of DNA double-strand breaks (DSBs) by homologous recombination (HR), the molecular mechanism underlying the tumor suppressor functions of FANCJ remains obscure. Here, we demonstrate that FANCJ deficient human and hamster cells exhibit reduction in the overall gene conversions in response to a site-specific chromosomal DSB induced by I-SceI endonuclease. Strikingly, the gene conversion events were biased in favour of long-tract gene conversions in FANCJ depleted cells. The fine regulation of short- (STGC) and long-tract gene conversions (LTGC) by FANCJ was dependent on its interaction with BRCA1 tumor suppressor. Notably, helicase activity of FANCJ was essential for controlling the overall HR and in terminating the extended repair synthesis during sister chromatid recombination (SCR). Moreover, cells expressing FANCJ pathological mutants exhibited defective SCR with an increased frequency of LTGC. These data unravel the novel function of FANCJ helicase in regulating SCR and SCR associated gene amplification/duplications and imply that these functions of FANCJ are crucial for the genome maintenance and tumor suppression. PMID:28911102

Cerebral visual impairment and intellectual disability caused by PGAP1 variants.

PubMed

Bosch, Daniëlle G M; Boonstra, F Nienke; Kinoshita, Taroh; Jhangiani, Shalini; de Ligt, Joep; Cremers, Frans P M; Lupski, James R; Murakami, Yoshiko; de Vries, Bert B A

2015-12-01

Homozygous variants in PGAP1 (post-GPI attachment to proteins 1) have recently been identified in two families with developmental delay, seizures and/or spasticity. PGAP1 is a member of the glycosylphosphatidylinositol anchor biosynthesis and remodeling pathway and defects in this pathway are a subclass of congenital disorders of glycosylation. Here we performed whole-exome sequencing in an individual with cerebral visual impairment (CVI), intellectual disability (ID), and factor XII deficiency and revealed compound heterozygous variants in PGAP1, c.274_276del (p.(Pro92del)) and c.921_925del (p.(Lys308Asnfs*25)). Subsequently, PGAP1-deficient Chinese hamster ovary (CHO)-cell lines were transfected with either mutant or wild-type constructs and their sensitivity to phosphatidylinositol-specific phospholipase C (PI-PLC) treatment was measured. The mutant constructs could not rescue the PGAP1-deficient CHO cell lines resistance to PI-PLC treatment. In addition, lymphoblastoid cell lines (LCLs) of the affected individual showed no sensitivity to PI-PLC treatment, whereas the LCLs of the heterozygous carrier parents were partially resistant. In conclusion, we report novel PGAP1 variants in a boy with CVI and ID and a proven functional loss of PGAP1 and show, to our knowledge, for the first time this genetic association with CVI.

Detection of early changes in lung cell cytology by flow-systems analysis techniques, July 1--December 31, 1975

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

Steinkamp, J.A.; Ingram, M.; Hansen, K.M.

1976-03-01

This report summarizes results of preliminary experiments to demonstrate the feasibility of using automated flow-systems analysis in detecting early changes of respiratory epithelium exposed to physical and chemical agents associated with the by-products of nonnuclear energy production. The Syrian hamster was selected as the experimental test animal to begin investigation of the effects of toxic agents to cells of the respiratory tract. Since initiation of the program approximately six months ago, the goals have been acquisition of adequate numbers of exfoliated cells from the lung; adaptation of cytological techniques developed on human exfoliated gynecological samples to hamster lung epithelium formore » obtaining single-cell suspensions; utilization of existing cell staining methods to measure DNA content in lung cells; and analysis of DNA content and cell size. As the flow-system cell analysis technology is adapted to the measurement of exfoliated lung cells, rapid and quantitative determination of early changes in the physical and biochemical cellular properties will be attempted as a function of exposure to the toxic agents. (auth)« less

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 contribute to BCA-PDT induced tumor necrosis.

Expression of estrogen receptor α 36 (ESR36) in the hamster ovary throughout the estrous cycle: effects of gonadotropins.

PubMed

Chakraborty, Prabuddha; Roy, Shyamal K

2013-01-01

Estradiol-17β (E) plays an important role in ovarian follicular development. Evidence indicates that some of the effect of E is mediated by the transmembrane estrogen receptor. In this study, we examined the spatio-temporal expression of recently discovered ERα36 (ESR36), a splice variant of Esr1 and a receptor for non-genomic E signaling, in the hamster ovary during the estrous cycle and the role of gonadotropins and ovarian steroid hormones in ESR36 expression. ESR36 expression was high on estrus (D1:0900 h) and declined precipitously by proestrus (D4:0900 h) and remained low up to D4:1600 h. Immunofluorescence findings corroborated immunoblot findings and revealed that ESR36 was expressed only in the cell membrane of both follicular and non-follicular cells, except the oocytes. Ovarian ESR36 was capable of binding to the E-affinity matrix, and have different molecular weight than that of the ESR1 or GPER. Hypophysectomy (Hx) resulted in a marked decline in ESR36 protein levels. FSH and LH, alone or combined, markedly upregulated ESR36 protein in Hx hamsters to the levels observed in D1 hamsters, but neither E nor P had any effect. Inhibition of the gonadotropin surge by phenobarbital treatment on D4:1100 h attenuated ESR36 expression in D1:0900 h ovaries, but the decline was restored by either FSH or LH replacement on D4 afternoon. This is the first report to show that ESR36, which is distinct from ESR1 or GPER is expressed in the plasma membrane of ovarian follicular and non-follicular cells, binds to E and its expression is regulated directly by the gonadotropins. In light of our previous findings, the results suggest that ovarian cells contain at least two distinct membrane estrogen receptors, such as GPER and ESR36, and strongly suggest for a non-genomic action of E regulating ovarian follicular functions.

Quantitative analysis of cellular glutathione by flow cytometry utilizing monochlorobimane: some applications to radiation and drug resistance in vitro and in vivo.

PubMed

Rice, G C; Bump, E A; Shrieve, D C; Lee, W; Kovacs, M

1986-12-01

An assay using a bimane derivative has been developed to detect free glutathione (GSH) in individual viable cells by flow cytometry. Monochlorobimane [syn-(ClCH2CH3)-1,5-diazabicycla[3.30]acta-3,6-diene-2,8-dio ne], itself nonfluorescent, reacts with GSH to form a highly fluorescent derivative. High pressure liquid chromatography analysis showed that, using specific staining conditions, the only low molecular weight fluorescent derivative formed in Chinese hamster ovary cells was that formed with GSH. Very little reaction with protein sulfhydryls was observed. Rates of GSH depletion in Chinese hamster ovary cells exposed to diethylmaleate were essentially the same, whether measured by relative fluorescence intensity, by flow cytometry or by enzymatic assay on cellular extracts. This method was shown to be useful for measurement of GSH resynthesis, uptake, and depletion by prolonged hypoxia and misonidazole treatment. Since measurements are made on individual cells, cell-to-cell variation and populational heterogeneity in GSH content are revealed by flow cytometry. Although under most conditions in vitro GSH content is relatively homogeneous, under certain circumstances, such as release from hypoxia, heterogeneity in populational GSH levels was observed. The significance of this heterogeneity is discussed in regard to the induction of gene amplification and drug resistance by transient hypoxia. Numerous subclones of Chinese hamster ovary cells selected by growth in Adriamycin or methotrexate-containing medium express elevated levels of GSH per cell. The method was extended to quantitate the GSH content of cells excised from EMT-6/SF mouse tumors that had been treated in vivo with L-buthionine-S-R-sulfoximine, an inhibitor of GSH synthesis. The bivariate analysis (forward angle light scatter versus monochlorobimane fluorescence) of cells derived from these tumors gave excellent resolution of normal and tumor cells and demonstrated extensive heterogeneity in the tumor cell population with respect to GSH content per cell.

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.

Molecular cloning of a murine homologue of membrane cofactor protein (CD46): preferential expression in testicular germ cells.

PubMed Central

Tsujimura, A; Shida, K; Kitamura, M; Nomura, M; Takeda, J; Tanaka, H; Matsumoto, M; Matsumiya, K; Okuyama, A; Nishimune, Y; Okabe, M; Seya, T

1998-01-01

Human membrane cofactor protein (MCP, CD46) has been suggested, although no convincing evidence has been proposed, to be a fertilization-associated protein, in addition to its primary functions as a complement regulator and a measles virus receptor. We have cloned a cDNA encoding the murine homologue of MCP. This cDNA showed 45% identity in deduced protein sequence and 62% identity in nucleotide sequence with human MCP. Its ectodomains were four short consensus repeats and a serine/threonine-rich domain, and it appeared to be a type 1 membrane protein with a 23-amino acid transmembrane domain and a short cytoplasmic tail. The protein expressed on Chinese hamster ovary cell transfectants was 47 kDa on SDS/PAGE immunoblotting, approximately 6 kDa larger than the murine testis MCP. It served as a cofactor for factor I-mediated inactivation of the complement protein C3b in a homologous system and, to a lesser extent, in a human system. Strikingly, the major message of murine MCP was 1.5 kb and was expressed predominantly in the testis. It was not detected in mice defective in spermatogenesis or with immature germ cells (until 23 days old). Thus, murine MCP may be a sperm-dominant protein the message of which is expressed selectively in spermatids during germ-cell differentiation. PMID:9461505

Neoplastic transformation of hamster embryo cells by heavy ions

NASA Astrophysics Data System (ADS)

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

1998-11-01

We have studied the induction of morphological transformation of Syrian hamster embryo cells by low doses of heavy ions with different linear energy transfer (LET), ranging from 13 to 400 keV/μm. Exponentially growing cells were irradiated with 12C or 28Si ion beams generated by the Heavy Ion Medical Accelerator in Chiba (HIMAC), inoculated to culture dishes, and transformed colonies were identified when the cells were densely stacked and showed a crisscross pattern. 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 250 kVp X-rays showed an initial increase with LET, reaching a maximum value of about 7 at 100 keV/μm, and then decreased with the further increase in LET. Thus, we confirmed that high LET heavy ions are significantly more effective than X-rays for the induction of in vitro cell transformation.

Neoplastic transformation of hamster embyro cells by heavy ions.

PubMed

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

1998-01-01

We have studied the induction of morphological transformation of Syrian hamster embryo cells by low doses of heavy ions with different linear energy transfer (LET), ranging from 13 to 400 keV/micrometer. Exponentially growing cells were irradiated with 12C or 28Si ion beams generated by the Heavy Ion Medical Accelerator in Chiba (HIMAC), inoculated to culture dishes, and transformed colonies were identified when the cells were densely stacked and showed a crisscross pattern. 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 250 kVp X-rays showed an initial increase with LET, reaching a maximum value of about 7 at 100 keV/micrometer, and then decreased with the further increase in LET. Thus, we confirmed that high LET heavy ions are significantly more effective than X-rays for the induction of in vitro cell transformation.

CHOgenome.org 2.0: Genome resources and website updates.

PubMed

Kremkow, Benjamin G; Baik, Jong Youn; MacDonald, Madolyn L; Lee, Kelvin H

2015-07-01

Chinese hamster ovary (CHO) cells are a major host cell line for the production of therapeutic proteins, and CHO cell and Chinese hamster (CH) genomes have recently been sequenced using next-generation sequencing methods. CHOgenome.org was launched in 2011 (version 1.0) to serve as a database repository and to provide bioinformatics tools for the CHO community. CHOgenome.org (version 1.0) maintained GenBank CHO-K1 genome data, identified CHO-omics literature, and provided a CHO-specific BLAST service. Recent major updates to CHOgenome.org (version 2.0) include new sequence and annotation databases for both CHO and CH genomes, a more user-friendly website, and new research tools, including a proteome browser and a genome viewer. CHO cell-line specific sequences and annotations facilitate cell line development opportunities, several of which are discussed. Moving forward, CHOgenome.org will host the increasing amount of CHO-omics data and continue to make useful bioinformatics tools available to the CHO community. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comparison of repair of DNA double-strand breaks in identical sequences in primary human fibroblast and immortal hamster-human hybrid cells harboring a single copy of human chromosome 11

NASA Technical Reports Server (NTRS)

Fouladi, B.; Waldren, C. A.; Rydberg, B.; Cooper, P. K.; Chatterjee, A. (Principal Investigator)

2000-01-01

We have optimized a pulsed-field gel electrophoresis assay that measures induction and repair of double-strand breaks (DSBs) in specific regions of the genome (Lobrich et al., Proc. Natl. Acad. Sci. USA 92, 12050-12054, 1995). The increased sensitivity resulting from these improvements makes it possible to analyze the size distribution of broken DNA molecules immediately after the introduction of DSBs and after repair incubation. This analysis shows that the distribution of broken DNA pieces after exposure to sparsely ionizing radiation is consistent with the distribution expected from randomly induced DSBs. It is apparent from the distribution of rejoined DNA pieces after repair incubation that DNA ends continue to rejoin between 3 and 24 h postirradiation and that some of these rejoining events are in fact misrejoining events, since novel restriction fragments both larger and smaller than the original fragment are generated after repair. This improved assay was also used to study the kinetics of DSB rejoining and the extent of misrejoining in identical DNA sequences in human GM38 cells and human-hamster hybrid A(L) cells containing a single human chromosome 11. Despite the numerous differences between these cells, which include species and tissue of origin, levels of TP53, expression of telomerase, and the presence or absence of a homologous chromosome for the restriction fragments examined, the kinetics of rejoining of radiation-induced DSBs and the extent of misrejoining were similar in the two cell lines when studied in the G(1) phase of the cell cycle. Furthermore, DSBs were removed from the single-copy human chromosome in the hamster A(L) cells with similar kinetics and misrejoining frequency as at a locus on this hybrid's CHO chromosomes.

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.

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.

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.

Targeted knock-in of an scFv-Fc antibody gene into the hprt locus of Chinese hamster ovary cells using CRISPR/Cas9 and CRIS-PITCh systems.

PubMed

Kawabe, Yoshinori; Komatsu, Shinya; Komatsu, Shodai; Murakami, Mai; Ito, Akira; Sakuma, Tetsushi; Nakamura, Takahiro; Yamamoto, Takashi; Kamihira, Masamichi

2018-05-01

Chinese hamster ovary (CHO) cells have been used as host cells for the production of pharmaceutical proteins. For the high and stable production of target proteins, the transgene should be integrated into a suitable genomic locus of host cells. Here, we generated knock-in CHO cells, in which transgene cassettes without a vector backbone sequence were integrated into the hprt locus of the CHO genome using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 and CRISPR-mediated precise integration into target chromosome (CRIS-PITCh) systems. We investigated the efficiency of targeted knock-in of transgenes using these systems. As a practical example, we generated knock-in CHO cells producing an scFv-Fc antibody using the CRIS-PITCh system mediated by microhomology sequences for targeting. We found that the CRIS-PITCh system can facilitate targeted knock-in for CHO cell engineering. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Endonuclease-independent LINE-1 retrotransposition at mammalian telomeres.

PubMed

Morrish, Tammy A; Garcia-Perez, José Luis; Stamato, Thomas D; Taccioli, Guillermo E; Sekiguchi, JoAnn; Moran, John V

2007-03-08

Long interspersed element-1 (LINE-1 or L1) elements are abundant, non-long-terminal-repeat (non-LTR) retrotransposons that comprise approximately 17% of human DNA. The average human genome contains approximately 80-100 retrotransposition-competent L1s (ref. 2), and they mobilize by a process that uses both the L1 endonuclease and reverse transcriptase, termed target-site primed reverse transcription. We have previously reported an efficient, endonuclease-independent L1 retrotransposition pathway (EN(i)) in certain Chinese hamster ovary (CHO) cell lines that are defective in the non-homologous end-joining (NHEJ) pathway of DNA double-strand-break repair. Here we have characterized EN(i) retrotransposition events generated in V3 CHO cells, which are deficient in DNA-dependent protein kinase catalytic subunit (DNA-PKcs) activity and have both dysfunctional telomeres and an NHEJ defect. Notably, approximately 30% of EN(i) retrotransposition events insert in an orientation-specific manner adjacent to a perfect telomere repeat (5'-TTAGGG-3'). Similar insertions were not detected among EN(i) retrotransposition events generated in controls or in XR-1 CHO cells deficient for XRCC4, an NHEJ factor that is required for DNA ligation but has no known function in telomere maintenance. Furthermore, transient expression of a dominant-negative allele of human TRF2 (also called TERF2) in XRCC4-deficient XR-1 cells, which disrupts telomere capping, enables telomere-associated EN(i) retrotransposition events. These data indicate that L1s containing a disabled endonuclease can use dysfunctional telomeres as an integration substrate. The findings highlight similarities between the mechanism of EN(i) retrotransposition and the action of telomerase, because both processes can use a 3' OH for priming reverse transcription at either internal DNA lesions or chromosome ends. Thus, we propose that EN(i) retrotransposition is an ancestral mechanism of RNA-mediated DNA repair associated with non-LTR retrotransposons that may have been used before the acquisition of an endonuclease domain.

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 suggesting that these fractions have chemopreventive effects on DMBA induced oral carcinogenesis.

Decreased risk of cholangiocarcinogenesis following repeated cycles of Opisthorchis viverrini infection-praziquantel treatment: Magnetic Resonance Imaging (MRI) and histopathological study in a hamster model.

PubMed

Hanpanich, Petcharakorn; Laha, Thewarach; Sripa, Banchob; Mairiang, Eimorn; Sereerak, Piya; Upontain, Songkaid; Tangkawattana, Prasarn; Brindley, Paul J; Tangkawattana, Sirikachorn

2017-08-01

It has been suggested that repeated infection of Opisthorchis viverrini followed by repeated treatment with praziquantel (PZQ) increases risk of development of cholangiocarcinoma (CCA). Evidence for the prediction has accumulated based on findings of indirect approaches involving molecular changes and epidemiological trends. By contrast, here we directly monitored the impact of repeated liver fluke infection and treatment with PZQ on cholangiocarcinogenesis in a rodent model of human opisthorchiasis, using magnetic resonance imaging (MRI) and histopathology. Twenty five Syrian golden hamsters were assigned to five treatment groups: 1) infection with O. viverrini (OV group), 2) treatment with the carcinogen N-nitrosodimethylamine (NDMA) at 12.5ppm (DMN), 3) O. viverrini infection in tandem with NDMA (OD), 4) O. viverrini infection, NDMA, and treatment with PZQ (ODP), and 5) uninfected, untreated control. The repeated infections were established by intragastric inoculation of 50 metacercariae of O. viverrini to the OV, OD and ODP hamsters at weeks 0, 5 and 10. PZQ at 300mg/kg body weight was given to each hamster of the ODP group on weeks 4, 9 and 13 (four weeks after each infection). Imaging by MRI was undertaken on weeks 5, 10 and 14 (i.e. one week after each PZQ treatment). MRI revealed that the ODP hamsters did not develop CCA, whereas necropsy at week 40 revealed CCA in hamsters of the OD and DMN groups. Findings for histopathology and for proliferating cell nuclear antigen index conformed to the MRI findings. In overview, and notwithstanding that the immune response of individual hosts may play roles in cholangiocarcinogenesis, three cycles of the infection with O. viverrini followed treatment of the infection with PZQ did not increase the risk of bile duct cancer in this hamster model of liver fluke infection-induced CCA. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

STATs profiling reveals predominantly-activated STAT3 in cholangiocarcinoma genesis and progression.

PubMed

Dokduang, Hasaya; Techasen, Anchalee; Namwat, Nisana; Khuntikeo, Narong; Pairojkul, Chawalit; Murakami, Yoshinori; Loilome, Watcharin; Yongvanit, Puangrat

2014-10-01

We investigated the aberrant expression of the STAT family in humans and liver fluke (Opisthorchis viverrini, Ov)-induced hamster cholangiocarcinoma (CCA) tissues. The expression and phosphorylation of STAT1, STAT2, STAT3, STAT4, STAT5a, STAT5b and STAT6 in human hamster CCA tissues were immunohistochemistry-profiled. Localizations of STAT5 in macrophages and lipopolysaccharide (LPS)-induced macrophage-conditioned media mediated STAT3 activation in CCA cells were demonstrated. The expressions of STAT 1-4 and 6 were detected in the cytoplasm of hyperplastic bile ducts and tumor cells, whereas STAT5a and STAT5b were observed in macrophages and connective tissues surrounding tumor, respectively. The expressions of STAT3 and STAT5b were significantly observed in tumors with a poorer histological differentiation. STAT3 expression was significantly associated with shorter survival of CCA patients and was predominately activated in CCA cell lines. In the CCA-hamsters, STATs expression was gradually increased along the carcinogenesis, especially at 30 days post-infection in which the inflammatory response was markedly observed, showing the correlation between the inflammation and STATs activation. Moreover, LPS-induced macrophage-conditioned media could mediate STAT3 activation in CCA cells. STAT3 is the major STAT, which plays roles in the inflammation that contributes to CCA carcinogenesis and progression and may serve as a marker for a poor prognosis of CCA. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

Cell-Matrix Interactions in Breast Carcinoma Invasion.

DTIC Science & Technology

1998-01-01

concentrated in hemidesmosomes, adhesive junctions which connect the basement membrane to the intracellular keratin cytoskeleton. In virtually all...fibronectin receptor contribute to the adhesive abnormalities of transformed fibroblasts by overexpressing this integrin in Chinese hamster ovary (CHO) cells...normal breast epithelium , the integrins expressed in breast carcinoma cells are diffusely distributed over the cell surface (Zutter et al., 1990

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.

Effect of heavy-ion beam irradiation on the level of serum soluble interleukin-2 receptors in hamster cheek pouch carcinoma model

PubMed Central

AN, XIAOLI; LI, MINGXIN; LI, NA; LIU, BIN; ZHANG, HONG; WANG, JIZENG

2014-01-01

Soluble interleukin-2 receptor (sIL-2R) is a glycoprotein derived from α chain of interleukin 2 receptors of mononuclear as well as T-cell membranes. The aims of this study were to detect the changes of serum soluble interleukin-2 receptor (sIL-2R) levels following heavy-ion beam irradiation in the hamster model with cheek pouch carcinoma, as well as to examine the impact of immune status of the hamster cheek pouch carcinoma model using heavy-ion beam irradiation. sIL-2R serum levels were detected by radioimmunoassay (RIA) in 40 hamsters bearing cheek pouch carcinoma prior to and following exposure to heavy-ion beam irradiation, and 8 normal animals served as the control. The sIL-2R serum level in hamster cheek pouch carcinoma model was significantly increased as compared to the normal control group (P<0.05). Results showed that an increase in the irradiation dose led to a gradual decrease in the sIL-2R serum level. Additionally, a statistical significance was observed compared to the tumor group (P<0.05). In conclusion, alterations in serum sIL-2R expression have an effect on the hamsters cheek pouch carcinoma model subsequent to heavy-ion beam irradiation. An increase in the irradiation dose indicated a decreased tendency in serum sIL-2R content. Detection of serum level changes may lead to an improved understanding of heavy-ion irradiation in vivo immune status, which is crucial for clinical diagnosis and prognosis. It can also provide a sensitive indicator to help estimate the effects of heavy-ion cancer targets. PMID:24748984

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.

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

Detection of early changes in lung-cell cytology by flow-systems analysis techniques. Progress report, January 1--June 30, 1976

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

Steinkamp, J. A.; Hansen, K. M.; Wilson, J. S.

1976-08-01

This report summarizes results of preliminary experiments to develop cytological and biochemical indicators for estimating damage to respiratory epithelium exposed to toxic agents associated with the by-products of nonnuclear energy production using advanced flow-systems cell-analysis technologies. Since initiation of the program one year ago, progress has been made in obtaining adequate numbers of exfoliated lung cells from the Syrian hamster for flow analysis; cytological techniques developed on human exfoliated gynecological samples have been adapted to hamster lung epithelium for obtaining single-cell suspensions; and lung-cell samples have been initially characterized based on DNA content, total protein, nuclear and cytoplasmic size, andmore » multiangle light-scatter measurements. Preliminary results from measurements of the above parameters which recently became available are described in this report. As the flow-systems technology is adapted further to analysis of exfoliated lung cells, measurements of changes in physical and biochemical cellular properties as a function of exposure to toxic agents will be performed.« less

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.

Adeno-associated virus (AAV)-3-based vectors transduce haematopoietic cells not susceptible to transduction with AAV-2-based vectors.

PubMed

Handa, A; Muramatsu, S; Qiu, J; Mizukami, H; Brown, K E

2000-08-01

Although adeno-associated virus (AAV)-2 has a broad tissue-host range and can transduce a wide variety of tissue types, some cells, such as erythro-megakaryoblastoid cells, are non-permissive and appear to lack the AAV-2 receptor. However, limited studies have been reported with the related dependovirus AAV-3. We have previously cloned this virus, characterized its genome and produced an infectious clone. In this study, the gene for green fluorescent protein (GFP) was inserted into AAV-2- and AAV-3-based plasmids and recombinant viruses were produced. These viruses were then used to transduce haematopoietic cells and the transduction efficiencies were compared. In contrast to recombinant (r) AAV-2, rAAV-3 successfully transduced erythroid and megakaryoblastoid cells, although rAAV-2 was superior in transduction of lymphocyte-derived cell lines. Recently, it was reported that heparan sulphate can act as a receptor of AAV-2. The infectivity of rAAV-2 and rAAV-3 was tested with mutant cell lines of Chinese hamster ovary cells that were defective for heparin or heparan sulphate expression on the cell surface. There was no correlation between the ability of rAAV-2 or rAAV-3 to infect cells and the cell surface expression of heparan sulphate and, although heparin blocked both rAAV-2 and rAAV-3 transduction, the ID(50) of rAAV-3 was higher than that of rAAV-2. In addition, virus-binding overlay assays indicated that AAV-2 and AAV-3 bound different membrane proteins. These results suggest not only that there are different cellular receptors for AAV-2 and AAV-3, but that rAAV-3 vectors may be preferred for transduction of some haematopoietic cell types.

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).

[Observation on alpha-SMA during Erigeron Breviscapus (Vant) Hand-Mazz obstructs the evolution of carcinogenesis of golden hamster cheek pouch].

PubMed

Zhou, C T; Zhang, S L; Ding, R Y; Hua, L; Zhong, W J

2000-06-01

To observe dynamically that Erigeron Breviscapus (Vant) Hand-Mazz (HEr) affects the expression of alpha-smooth muscle actin (alpha-SMA). To discuss the probable mechanism of obstructing leukoplakia carcinogenesis of this medicine. 120 golden hamsters were randomly divided into model group (48), HEr group (48) and control group (6). HEr was applied to obstruct the evolution of carcinogenesis of golden hamster cheek pouch. Immunohistochemistry was used to detect the expression level of alpha-SMA with cheek pouch specimen that besmears DMBA in 4-9 weeks. Results were compared with model group. Vessel density dyed with alpha-SMA continuously of HEr group was 65.76 significantly higher than that of model group 42.12 (P<0.001). High classification cases in HEr group were much more than model group when cases were divided into five groups as follow: 100%, 50%, 20%, 10%, 3% (P<0.01). HEr can raise the expression level of alpha-SMA exactly during the evolution of leukoplakia carcinogenesis of golden hamster, which shows that this medicine obstructs carcinogenesis by keeping the normal physiological function of vascular myoepithelial cell and integrity of vascular basement membrane.

Occurrence, Synthesis and Mammalian Cell Cytotoxicity and Genotoxicity of Haloacetamides: An Emerging Class of Nitrogenous Drinking Water Disinfection By-Products

EPA Science Inventory

The haloacetamides, a class of emerging nitrogenous drinking water disinfection by-products (DBPs), were analyzed for their chronic cytotoxicity and for the induction of genomic DNA damage in Chinese hamster ovary cells.

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.

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.

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.

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.

Hypolipidemic activity and mechanisms of the total phenylpropanoid glycosides from Ligustrum robustum (Roxb.) Blume by AMPK-SREBP-1c pathway in hamsters fed a high-fat diet.

PubMed

Yang, Runmei; Chu, Xinxin; Sun, Le; Kang, Zhuoying; Ji, Min; Yu, Ying; Liu, Ying; He, Zhendan; Gao, Nannan

2018-04-01

The aim of this study was to evaluate the hypolipidemic effect and mechanisms of total phenylpropanoid glycosides extracted from Ligustrum robustum (Roxb.) Blume (LRTPG) in hamsters fed a high-fat diet and to discover bioactive components in HepG2 cell model induced by oleic acid. LRTPG of high (1.2 g/kg), medium (0.6 g/kg), and low (0.3 g/kg) doses was administrated daily for 21 consecutive days in hamsters. We found that in hamsters fed a high-fat diet, LRTPG effectively reduced the concentrations of plasma triglycerides (TG), free fatty acid, total cholesterol, low-density lipoprotein cholesterol, and hepatic TG and total cholesterol. And the compounds acteoside, ligupurpuroside A, ligupurpuroside C, and ligupurpuroside D significantly inhibited lipid accumulation in HepG2 cell at the concentration of 50 μmol/L. Mechanism research demonstrated that LRTPG increased the levels of phospho-AMP-activated protein kinase and phospho-sterol regulatory element binding protein-1c in liver, further to suppress the downstream lipogenic genes as stearoyl-CoA desaturase 1, glycerol-3-phosphate acyltransferase, 1-acylglycerol-3-phosphate O-acyltransferase 2, and diacylglycerol acyltransferase 2. In addition, LRTPG increased the hydrolysis of circulating TG by up-regulating lipoprotein lipase activities. These results indicate that LRTPG prevents hyperlipidemia via activation of hepatic AMP-activated protein kinase-sterol regulatory element binding protein-1c pathway. Copyright © 2018 John Wiley & Sons, Ltd.

Insulin-like Growth Factor (IGF) Signaling Requires αvβ3-IGF1-IGF Type 1 Receptor (IGF1R) Ternary Complex Formation in Anchorage Independence, and the Complex Formation Does Not Require IGF1R and Src Activation

PubMed Central

Fujita, Masaaki; Takada, Yoko K.; Takada, Yoshikazu

2013-01-01

Integrin αvβ3 plays a role in insulin-like growth factor 1 (IGF1) signaling (integrin-IGF1 receptor (IGF1R) cross-talk) in non-transformed cells in anchorage-dependent conditions. We reported previously that IGF1 directly binds to αvβ3 and induces αvβ3-IGF1-IGF1R ternary complex formation in these conditions. The integrin-binding defective IGF1 mutant (R36E/R37E) is defective in inducing ternary complex formation and IGF signaling, whereas it still binds to IGF1R. We studied if IGF1 can induce signaling in anchorage-independent conditions in transformed Chinese hamster ovary cells that express αvβ3 (β3-CHO) cells. Here we describe that IGF1 signals were more clearly detectable in anchorage-independent conditions (polyHEMA-coated plates) than in anchorage-dependent conditions. This suggests that IGF signaling is masked by signals from cell-matrix interaction in anchorage-dependent conditions. IGF signaling required αvβ3 expression, and R36E/R37E was defective in inducing signals in polyHEMA-coated plates. These results suggest that αvβ3-IGF1 interaction, not αvβ3-extracellular matrix interaction, is essential for IGF signaling. Inhibitors of IGF1R, Src, AKT, and ERK1/2 did not suppress αvβ3-IGF-IGF1R ternary complex formation, suggesting that activation of these kinases are not required for ternary complex formation. Also, mutations of the β3 cytoplasmic tail (Y747F and Y759F) that block β3 tyrosine phosphorylation did not affect IGF1R phosphorylation or AKT activation. We propose a model in which IGF1 binding to IGF1R induces recruitment of integrin αvβ3 to the IGF-IGF1R complex and then β3 and IGF1R are phosphorylated. It is likely that αvβ3 should be together with the IGF1-IGF1R complex for triggering IGF signaling. PMID:23243309

Effect of steady magnetic field on human lymphocytes

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

Mileva, M.; Ivanov, B.; Bulanova, M.

1983-01-01

Exposure to steady magnetic field (SMF) for different periods of time did not elicit statistically reliable increase in chromosome aberrations in human peripheral blood lymphocytes. Metaphase analysis of Crepis capilaris cells revealed that SMF (9 k0e, 200 0e/cm) for 2 days did not induce chromosome aberrations. Nor were any changes demonstrated in roots of beans, onions and L-fibroblasts of subcutaneous tissue of mice and Chinese hamsters. The obtained data are indicative of absence of cytogenetic effect of SMF. The level and spectrum of chromosome aberrations did not exceed the values for spontaneous chromatic fragments in cultures. Cytogenetic analysis of DEDEmore » cells of the Chinese hamster revealed a mild mutagenic effect of SMF. Chromosomal aberrations were also demonstrated after exposure (5 min) of garlic roots.« less

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

Specificity, Size, and Frequency of Spaces That Characterize the Mechanism of Bulk Transepithelial Transport of Prions in the Nasal Cavities of Hamsters and Mice

PubMed Central

Ayers, J. I.; Bartz, J. C.

2016-01-01

ABSTRACT Inhalation of infected brain homogenate results in transepithelial transport of prions across the nasal mucosa of hamsters, some of which occurs rapidly in relatively large amounts between cells (A. E. Kincaid, K. F. Hudson, M. W. Richey, and J. C. Bartz, J. Virol 86:12731–12740, 2012, doi:http://dx.doi.org/10.1128/JVI.01930-12). Bulk transepithelial transport in the nasal cavity has not been studied to date. In the present study, we characterized the frequency, size, and specificity of the intercellular spaces that mediate the bulk transport of inhaled prions between cells of mice or hamsters following extranasal inoculation with mock-infected brain homogenate, different strains of prion-infected brain homogenate, or brain homogenate mixed with India ink. Infected or mock-infected inoculum was identified within lymphatic vessels of the lamina propria and in spaces of >5 μm between a small number of cells of the nasal mucosa in >90% of animals from 5 to 60 min after inhalation. The width of the spaces between cells, the amount of the inoculum within the lumen of lymphatic vessels, and the timing of the transport indicate that this type of transport was taking place through preexisting spaces in the nasal cavity that were orders of magnitude wider than what is normally reported for paracellular transport. The indiscriminate rapid bulk transport of brain homogenate in the nasal cavity results in immediate entry into nasal cavity lymphatics following inhalation. This novel mechanism may underlie the recent report of the early detection of prions in blood following inhalation and has implications for horizontal prion transmission. IMPORTANCE The results of these studies demonstrate that the nasal mucosa of mice and hamsters is not an absolute anatomical barrier to inhaled prion-infected or uninfected brain homogenate. Relatively large amounts of infected and uninfected brain homogenate rapidly cross the nasal mucosa and enter the lumen of lymphatic vessels following inhalation. These bulk transepithelial transport events were relatively rare but present in >90% of animals 5 to 60 min following inhalation. This novel mechanism of bulk transepithelial transport was seen in experimental and control hamsters and mice, indicating that it was not species specific or in response to prion exposure. The indiscriminate bulk intercellular transport of inhaled pathogens across the nasal mucosa followed by entry into the lymphatic system may be a mechanism that underlies the entry and spread of other toxins and pathogens in olfactory system-driven animals. PMID:27384659

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.

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

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.

FH Afrikaner-3 LDL receptor mutation results in defective LDL receptors and causes a mild form of familial hypercholesterolemia.

PubMed

Graadt van Roggen, J F; van der Westhuyzen, D R; Coetzee, G A; Marais, A D; Steyn, K; Langenhoven, E; Kotze, M J

1995-06-01

Three founder-related gene mutations (FH Afrikaner-1, -2, and -3) that affect the LDL receptor are responsible for 90% of the familial hypercholesterolemia (FH) in South African Afrikaners. Patients heterozygous for the FH Afrikaner-1 (FH1) mutation, which results in receptors having approximately 20% of normal receptor activity, have significantly lower plasma cholesterol levels and milder clinical symptoms than heterozygotes with the FH Afrikaner-2 mutation, which completely abolishes LDL receptor activity. In this study we re-created the FH3 mutation (Asp154-->Asn) in exon 4 by site-directed mutagenesis and analyzed the expression of the mutant receptors in Chinese hamster ovary cells. The mutation resulted in the formation of LDL receptors that are markedly defective in their ability to bind LDL, whereas binding of apoE-containing beta-VLDL is less affected. The mutant receptors are poorly expressed on the cell surface as a result of significant degradation of receptor precursors. The plasma cholesterol levels of 31 FH3 heterozygotes were similar to FH1 heterozygotes but significantly lower than FH2 heterozygotes. The FH1 and FH3 heterozygotes also tended to be less severely affected clinically (by coronary heart disease and xanthomata) than FH2 patients. This study demonstrates that mutational heterogeneity in the LDL receptor gene influences the phenotypic expression of heterozygous FH and that severity of expression correlates with the activity of the LDL receptor measured in vitro. The results further indicate that knowledge of the specific mutation underlying FH in heterozygotes is valuable in determining the potential risk of premature atherosclerosis and should influence the clinical management of FH patients.

NEURAL ORGANIZATION OF SENSORY INFORMATIONS FOR TASTE,

DTIC Science & Technology

TASTE , ELECTROPHYSIOLOGY), (*NERVES, *TONGUE), NERVE CELLS, NERVE IMPULSES, PHYSIOLOGY, NERVOUS SYSTEM, STIMULATION(PHYSIOLOGY), NERVE FIBERS, RATS...HAMSTERS, STIMULATION(PHYSIOLOGY), PERCEPTION, COOLING, BEHAVIOR, PSYCHOPHYSIOLOGY, TEMPERATURE, THRESHOLDS(PHYSIOLOGY), CHEMORECEPTORS , STATISTICAL ANALYSIS, JAPAN

Measurement of Bluetongue Virus Binding to a Mammalian Cell Surface Receptor by an In Situ Immune Fluorescent Staining Technique

USDA-ARS?s Scientific Manuscript database

A quantifiable in situ immune fluorescent assay (IFA) was developed to measure bluetongue virus (BTV) binding to mammalian cells. The utility of the assay was demonstrated with both Chinese hamster ovary (CHO) and bovine pulmonary artery endothelial (CPAE) cells. Since heparin sulfate (HS) has been ...

Growing And Assembling Cells Into Tissues

NASA Technical Reports Server (NTRS)

Wolf, David A.; Schwarz, Ray P.; Lewis, Marian L.; Cross, John H.; Huls, M. Helen

1990-01-01

Laboratory process for growth and assembly of mammalian cells into tissue-like masses demonstrated with hamster and rat cells. New process better able to provide culture environment with reduced fluid shear stress, freedom for three-dimensional spatial orientation of particles suspended in culture medium, and localization of particles of different or similar sedimentation properties in similar spatial region.

Studies on the inhalation toxicology of two fiberglasses and amosite asbestos in the syrian golden hamster. Part I. Results of a subchronic study and dose selection for a chronic study.

PubMed

Hesterberg, T W; Axten, C; McConnell, E E; Hart, G A; Miiller, W; Chevalier, J; Everitt, J; Thevenaz, P; Oberdörster, G

1999-09-01

A multidose, subchronic inhalation study was used to estimate the maximum tolerated dose (MTD) of 901 fiberglass (MMVF10.1) for a chronic inhalation study using hamsters. Subchronic study results indicated that 30 mg/m(3) [250-300 WHO fibers (>5 microm long)/cm(3) and 100-130 fibers/cm(3) >20 microm long] meets or exceeds the estimated MTD, and chronic study results confirmed this. For the subchronic study, hamsters were exposed 6 h/day, 5 days/wk, for 13 wk to MMVF10.1 at 3, 16, 30, 45, and 60 mg/m(3) (36, 206, 316, 552, or 714 WHO fibers/cm(3)), then monitored for 10 wk. Results demonstrating MTD were: inflammatory response (all fiber exposures); elevated lung cell proliferation with @ges;16 mg/m(3); lung lavage neutrophil elevations with @ges;16 mg/m(3) and lactate dehydrogenase (LDH) and protein elevations with > or = 30 mg/m(3); and persistent abnormal macrophage/fiber clumps in lungs exposed to 45 and 60 mg/m(3), which suggest overloading of clearance mechanisms. For the chronic study, hamsters were exposed for 78 wk to MMVF10a (901 fiber glass) or MMVF33 (special-application 475 fiberglass) at approximately 300 WHO fibers/cm(3) ( approximately 100 fibers/cm(3) @gt;20 @mu;m long), or to amosite asbestos at an equivalent concentration and 2 lower concentrations. All fiber-exposed animals had pulmonary inflammation, elevated lung lavage cells, and increased lung cell proliferation. Between 52 and 78 wk of exposure, lung burdens of all fibers increased at an accelerated rate, suggesting impairment of clearance mechanisms. MMVF33 and amosite induced fibrosis and pleural mesothelioma. These findings substantiate that exposures in the chronic study adequately tested the toxic potential of fiberglass.

Box C/D small nucleolar RNA (snoRNA) U60 regulates intracellular cholesterol trafficking.

PubMed

Brandis, Katrina A; Gale, Sarah; Jinn, Sarah; Langmade, Stephen J; Dudley-Rucker, Nicole; Jiang, Hui; Sidhu, Rohini; Ren, Aileen; Goldberg, Anna; Schaffer, Jean E; Ory, Daniel S

2013-12-13

Mobilization of plasma membrane (PM) cholesterol to the endoplasmic reticulum is essential for cellular cholesterol homeostasis. The mechanisms regulating this retrograde, intermembrane cholesterol transfer are not well understood. Because mutant cells with defects in PM to endoplasmic reticulum cholesterol trafficking can be isolated on the basis of resistance to amphotericin B, we conducted an amphotericin B loss-of-function screen in Chinese hamster ovary (CHO) cells using insertional mutagenesis to identify genes that regulate this trafficking mechanism. Mutant line A1 displayed reduced cholesteryl ester formation from PM-derived cholesterol and increased de novo cholesterol synthesis, indicating a deficiency in retrograde cholesterol transport. Genotypic analysis revealed that the A1 cell line contained one disrupted allele of the U60 small nucleolar RNA (snoRNA) host gene, resulting in haploinsufficiency of the box C/D snoRNA U60. Complementation and mutational studies revealed the U60 snoRNA to be the essential feature from this locus that affects cholesterol trafficking. Lack of alteration in predicted U60-mediated site-directed methylation of 28 S rRNA in the A1 mutant suggests that the U60 snoRNA modulates cholesterol trafficking by a mechanism that is independent of this canonical function. Our study adds to a growing body of evidence for participation of small noncoding RNAs in cholesterol homeostasis and is the first to implicate a snoRNA in this cellular function.

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

Structural changes in plasma membranes prepared from irradiated Chinese hamster V79 cells as revealed by Raman spectroscopy

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

Verma, S.P.; Sonwalkar, N.

1991-04-01

The effect of gamma irradiation on the integrity of plasma membranes isolated from Chinese hamster V79 cells was investigated by Raman spectroscopy. Plasma membranes of control V79 cells show transitions between {minus}10 and 5{degree}C (low-temperature transition), 10 and 22{degree}C (middle-temperature transition), and 32 and 40{degree}C (high-temperature transition). Irradiation (5 Gy) alters these transitions markedly. First, the low-temperature transition shifts to higher temperature (onset and completion temperatures 4 and 14{degree}C). Second, the middle-temperature transition shifts up to the range of about 20-32{degree}C, but the width remains unchanged. Third, the higher temperature transition broadens markedly and shifts to the range of aboutmore » 15-40{degree}C. Protein secondary structure as determined by least-squares analysis of the amide I bands shows 36% total helix, 55% total beta-strand, and 9% turn plus undefined for control plasma membrane proteins. Plasma membrane proteins of irradiated V79 cells show an increase in total helix (40 and 45% at 5 and 10 Gy, respectively) and a decrease in the total beta-strand (48 and 44% at 5 and 10 Gy, respectively) structures. The qualitative analysis of the Raman features of plasma membranes and model compounds in the 1600 cm-1 region, assigned to tyrosine groups, revealed that irradiation alters the microenvironment of these groups. We conclude that the radiation dose used in the survival range of Chinese hamster V79 cells can cause damage to plasma membrane proteins without detectable lipid peroxidation, and that the altered proteins react differently with lipids, yielding a shift in the thermal transition properties.« less

Morphological characterization of sprouting and intussusceptive angiogenesis by SEM in oral squamous cell carcinoma.

PubMed

Oliveira de Oliveira, Laura Beatriz; Faccin Bampi, Vinícius; Ferreira Gomes, Carolina; Braga da Silva, Jefferson Luis; Encarnação Fiala Rechsteiner, Sandra Mara

2014-01-01

The word angiogenesis indicates the formation of new vascular segments from existing vessels such as capillaries and venules. Blood vessel formation in tumors is the result of rapid, disorganized vascular growth through two distinct mechanisms: sprouting and intussusceptive angiogenesis. The objective of this study was to elucidate the morphological aspects of these two vascular growth mechanisms in oral squamous cell carcinoma induced in hamster buccal pouch. Eight Syrian golden hamsters had their right buccal pouch treated with DMBA 0.5% and 10% carbamide peroxide for 90 days in order to produce squamous cell carcinoma in this site. Next, buccal pouches of the animals were submitted to the vascular corrosion technique and then analyzed by scanning electron microscopy. The vascular figures of sprouts were observed in the entire vascular network of the buccal pouches, as opposed to the intussusceptive angiogenesis that was predominantly observed in the sub-epithelial network. It was possible to differentiate the figures of sprouts from artifacts by the analysis of the blind ending of these structures. Intussusceptive angiogenesis was identified by the presence of holes trespassing the lumen of the capillaries. Vascular expansion occurred through intussusceptive angiogenesis in two ways: by the fusion of the pillars to form a new capillary and, by increasing the girth of the pillar to form meshes. The method of corrosion associated with scanning electron microscopy proved to be an excellent tool to study the two types of angiogenesis in oral squamous cell carcinoma in the hamster buccal pouch. © 2013 Wiley Periodicals, Inc.

Spontaneous and induced aneuploidy, considerations which may influence chromosome malsegregation.

PubMed

Parry, James M; Al-Obaidly, A; Al-Walhaib, M; Kayani, M; Nabeel, T; Strefford, J; Parry, E M

2002-07-25

Aneuploidy plays a major role in the production of human birth defects and is becoming increasingly recognised as a critical event in the etiology of a wide range of human cancers. Thus, the detection of aneuploidy and the characterisation of the mechanisms which lead to chromosome malsegregation is an important area of genotoxicological research. As an aid to aneuploidy research, methods have been developed to analyse the mechanisms of chromosome malsegregation and to investigate the role of aneuploidy in tumour progression. The presence of aneuploid cells is a common characteristic of many of tumour cell types as illustrated by the wide range of chromosome number changes detected in post-menopausal breast tumours. To investigate the time of occurrence of aneuploidy during tumour progression, we have studied the chromosome number status of Syrian hamster dermal (SHD) cells cultures progressing to morphological transformation. The production of both polyploid and aneuploid cells is a common feature of progressing cells in this model. The elevation of both progression to morphological transformation and aneuploid frequencies can be produced by exposure to a diverse range of carcinogens and tumour promoters. Analysis of the genotoxic activity of the hormone 17-beta oestradiol demonstrated its ability to induce both chromosome loss and non-disjunction in human lymphoblastoid cells implicating aneugenic activity in hormone related cancers. Mutations in the p53 tumour suppressor gene introduced into human fibroblasts produced modifications in chromosome separation at mitosis which may lead to the production of both aneuploidy and polyploid cells. Our studies indicate that the production of aneuploid cells can be influenced by both endogenous and exogenous factors and occur throughout the progression of normal cells to a malignant phenotype.

[6]-Shogaol attenuates inflammation, cell proliferation via modulate NF-κB and AP-1 oncogenic signaling in 7,12-dimethylbenz[a]anthracene induced oral carcinogenesis.

PubMed

Annamalai, Govindhan; Suresh, Kathiresan

2018-02-01

Nuclear factor-kappaB (NF-κB) and activator protein 1 (AP-1) is a major transcription factor which regulates many biological and pathological processes such as inflammation and cell proliferation, which are major implicates in cancer progression. [6]-Shogaol ([6]-SHO) is a major constituent of ginger, exhibits various biological properties such as anti-oxidants, anti-inflammation and anti-tumor. Recently, we proven that [6]-SHO prevents oral squamous cell carcinoma by activating proapoptotic factors in in vitro and in vivo experimental model. However, the preventive efficacy of [6]-SHO in 7,12-dimethylbenz[a]anthracene (DMBA) induced hamster buccal pouch carcinogenesis (HBP) has not been fully elucidated, so far. Hence, we aimed to investigate the effect of [6]-SHO on inflammation and cell proliferation by inhibiting the translocation of NF-κB and AP-1 in DMBA induced HBP carcinogenesis. In this study, we observed upregulation of inflammatory markers (COX-2, iNOS, TNF-α, interleukin-1 and -6), cell proliferative markers (Cyclin D1, PCNA and Ki-67) and aberrant activation of NF-κB, AP-1, IKKβ, c-jun, c-fos and decreased IκB-α in DMBA induced hamsters. Conversely, oral administration of [6]-SHO strongly inhibited constitutive phosphorylation and degradation of IκB and inhibit phosphorylation of c-jun, c-fos, resulting in inhibition of nuclear translocation of NF-κBp65 and AP-1. Thus, inhibition of NF-κB and AP-1 activation by [6]-SHO attenuates inflammation and cell proliferative response in DMBA induced hamsters. Our finding suggested that [6]-SHO is a novel functional agent capable of preventing DMBA induced inflammation and cell proliferation associated tumorigenesis by modulating multiple signalling molecules. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

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.

Ultrasound Backscatter Microscopy for Imaging of Oral Carcinoma

PubMed Central

Lam, Matthew; Chaudhari, Abhijit J.; Sun, Yang; Zhou, Feifei; Dobbie, Allison; Gandour-Edwards, Regina F.; Tinling, Steve P.; Farwell, D. Gregory; Monsky, Wayne L.; Shung, K. Kirk; Marcu, Laura

2013-01-01

Objectives Ultrasound backscatter microscopy (UBM), or ultrasound biomicroscopy, is a noninvasive, label-free, and ionizing radiation–free technique allowing high-resolution 3-dimensional structural imaging. The goal of this study was to evaluate UBM for resolving anatomic features associated with squamous cell carcinoma of the oral cavity. Methods The study was conducted in a hamster buccal pouch model. A carcinogen was topically applied to cheeks of 14 golden Syrian hamsters. Six additional hamsters served as healthy controls. A high-frequency (41 MHz, 6-mm focal depth, lateral and axial resolutions of 65 and 37 μm, respectively) UBM system was used for scanning the oral cavity after 14 weeks of carcinogen application. Histologic analyses were conducted on scanned regions. Results The histologic structure of buccal tissue and microvasculature networks could be visualized from the UBM images. Epithelial and mucosal hypertrophy and neoplastic changes were identified in animals subjected to the carcinogen. In animals with invasive squamous cell carcinoma, lesion development and destruction of the structural integrity of tissue layers were noted. Conclusions In this pilot study, UBM generated sufficient contrast for morphologic features associated with oral carcinoma compared to healthy tissue. This modality may present a practical technique for detection of oral neoplasms that is potentially translatable to humans. PMID:24065260

Altered microRNA expression patterns during the initiation and promotion stages of neonatal diethylstilbestrol-induced dysplasia/neoplasia in the hamster (Mesocricetus auratus) uterus.

PubMed

Padmanabhan, Ramesh; Hendry, Isabel R; Knapp, Jennifer R; Shuai, Bin; Hendry, William J

2017-10-01

Treatment of Syrian hamsters on the day of birth with the prototypical endocrine disruptor and synthetic estrogen, diethylstilbestrol (DES), leads to 100% occurrence of uterine hyperplasia/dysplasia in adulthood, a large proportion of which progress to neoplasia (endometrial adenocarcinoma). Consistent with our prior gene expression analyses at the mRNA and protein levels, we now report (based on microarray, real-time polymerase chain reaction, and in situ hybridization analyses) that progression of the neonatal DES-induced dysplasia/neoplasia phenomenon in the hamster uterus also includes a spectrum of microRNA expression alterations (at both the whole-organ and cell-specific level) that differ during the initiation (upregulated miR-21, 200a, 200b, 200c, 29a, 29b, 429, 141; downregulated miR-181a) and promotion (downregulated miR-133a) stages of the phenomenon. The biological processes targeted by those differentially expressed miRNAs include pathways in cancer and adherens junction, plus regulation of the cell cycle, apoptosis, and miRNA functions, all of which are consistent with our model system phenotype. These findings underscore the need for continued efforts to identify and assess both the classical genetic and the more recently recognized epigenetic mechanisms that truly drive this and other endocrine disruption phenomena.

Primary lymph node responses to mosquito bites.

PubMed

Mellink, J J; Vos, B J

1977-03-29

Post-auricular lymph node responses and changes in fresh weight of thymus and spleen of hamsters and mice at 4 and 8 days after primary exposure of both ears to 20 bites by the mosquito Aedes aegypti were studied quantitatively. In both hosts lymph node changes characteristic of the development of cell-mediated immune responses and those which are believed to lead to antibody production occurred, with the emphasis on the latter phenomena. No reactions of thymus and spleen were observed. The responses recorded are considered to be immunologically specific. In hamsters, but not in mice, the responses related to humoral sensitization coincided in time to a large extent with those of the cell-mediated immune processes. The stronger humoral responses in mice were probably in the first place the result of the relatively higher dosages applied.

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.

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

Feline leukemia virus infection requires a post-receptor binding envelope-dependent cellular component.

PubMed

Hussain, Naveen; Thickett, Kelly R; Na, Hong; Leung, Cherry; Tailor, Chetankumar S

2011-12-01

Gammaretrovirus receptors have been suggested to contain the necessary determinants to mediate virus binding and entry. Here, we show that murine NIH 3T3 and baby hamster kidney (BHK) cells overexpressing receptors for subgroup A, B, and C feline leukemia viruses (FeLVs) are weakly susceptible (10(1) to 10(2) CFU/ml) to FeLV pseudotype viruses containing murine leukemia virus (MLV) core (Gag-Pol) proteins, whereas FeLV receptor-expressing murine Mus dunni tail fibroblast (MDTF) cells are highly susceptible (10(4) to 10(6) CFU/ml). However, NIH 3T3 cells expressing the FeLV subgroup B receptor PiT1 are highly susceptible to gibbon ape leukemia virus pseudotype virus, which differs from the FeLV pseudotype viruses only in the envelope protein. FeLV resistance is not caused by a defect in envelope binding, low receptor expression levels, or N-linked glycosylation. Resistance is not alleviated by substitution of the MLV core in the FeLV pseudotype virus with FeLV core proteins. Interestingly, FeLV resistance is alleviated by fusion of receptor-expressing NIH 3T3 and BHK cells with MDTF or human TE671 cells, suggesting the absence of an additional cellular component in NIH 3T3 and BHK cells that is required for FeLV infection. The putative FeLV-specific cellular component is not a secreted factor, as MDTF conditioned medium does not alleviate the block to FeLV infection. Together, our findings suggest that FeLV infection requires an additional envelope-dependent cellular component that is absent in NIH 3T3 and BHK cells but that is present in MDTF and TE671 cells.

in Vitro and in Vivo Inhibitory Effects of α-Mangostin on Cholangiocarcinoma Cells and Allografts

PubMed Central

Aukkanimart, Ratchadawan; Boonmars, Thidarut; Sriraj, Pranee; Sripan, Panupan; Songsri, Jiraporn; Ratanasuwan, Panaratana; Laummaunwai, Porntip; Boueroy, Parichart; Khueangchaingkhwang, Sukhonthip; Pumhirunroj, Benjamabhorn; Artchayasawat, Atchara; Boonjaraspinyo, Sirintip; Wu, Zhiliang; Hahnvajanawong, Chariya; Vaeteewoottacharn, Kulthida; Wongkham, Sopit

2017-01-01

We investigated the anti-cholangiocarcinoma effect of α-mangostin from Garcinia mangostana pericarp extract (GM) in a human cholangiocarcinoma (CCA) cell line and a hamster CCA allograft model. In vitro, human CCA cells were treated with GM at various concentrations and for different time periods; then cell-cycle arrest and apoptosis were evaluated using flow cytometry, and metastatic potential with wound healing assays. In vivo, hamster allografts were treated with GM, gemcitabine (positive control) and a placebo (negative control) for 1 month; tumor weight and volume were then determined. Histopathological features and immunostaining (CK19 and PCNA) characteristics were examined by microscopy. The present study found that α-mangostin could: inhibit CCA cell proliferation by inducing apoptosis through the mitochondrial pathway; induce G1 cell-cycle arrest; and inhibit metastasis. Moreover, α-mangostin could inhibit CCA growth, i.e. reduce tumor mass (weight and size) and alter CCA pathology, as evidenced by reduced positive staining for CK19 and PCNA. The present study thus suggested that α-mangostin is a promising anti-CCA compound whose ready availability in tropical countries might indicate use for prevention and treatment of CCA. PMID:28441703

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

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.

[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.

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.

Curcuma oil attenuates accelerated atherosclerosis and macrophage foam-cell formation by modulating genes involved in plaque stability, lipid homeostasis and inflammation.

PubMed

Singh, Vishal; Rana, Minakshi; Jain, Manish; Singh, Niharika; Naqvi, Arshi; Malasoni, Richa; Dwivedi, Anil Kumar; Dikshit, Madhu; Barthwal, Manoj Kumar

2015-01-14

In the present study, the anti-atherosclerotic effect and the underlying mechanism of curcuma oil (C. oil), a lipophilic fraction from turmeric (Curcuma longa L.), was evaluated in a hamster model of accelerated atherosclerosis and in THP-1 macrophages. Male golden Syrian hamsters were subjected to partial carotid ligation (PCL) or FeCl3-induced arterial oxidative injury (Ox-injury) after 1 week of treatment with a high-cholesterol (HC) diet or HC diet plus C. oil (100 and 300 mg/kg, orally). Hamsters fed with the HC diet were analysed at 1, 3 and 5 weeks following carotid injury. The HC diet plus C. oil-fed group was analysed at 5 weeks. In hyperlipidaemic hamsters with PCL or Ox-injury, C. oil (300 mg/kg) reduced elevated plasma and aortic lipid levels, arterial macrophage accumulation, and stenosis when compared with those subjected to arterial injury alone. Similarly, elevated mRNA transcripts of matrix metalloproteinase-2 (MMP-2), MMP-9, cluster of differentiation 45 (CD45), TNF-α, interferon-γ (IFN-γ), IL-1β and IL-6 were reduced in atherosclerotic arteries, while those of transforming growth factor-β (TGF-β) and IL-10 were increased after the C. oil treatment (300 mg/kg). The treatment with C. oil prevented HC diet- and oxidised LDL (OxLDL)-induced lipid accumulation, decreased the mRNA expression of CD68 and CD36, and increased the mRNA expression of PPARα, LXRα, ABCA1 and ABCG1 in both hyperlipidaemic hamster-derived peritoneal and THP-1 macrophages. The administration of C. oil suppressed the mRNA expression of TNF-α, IL-1β, IL-6 and IFN-γ and increased the expression of TGF-β in peritoneal macrophages. In THP-1 macrophages, C. oil supplementation prevented OxLDL-induced production of TNF-α and IL-1β and increased the levels of TGF-β. The present study shows that C. oil attenuates arterial injury-induced accelerated atherosclerosis, inflammation and macrophage foam-cell formation.

Neural mechanisms controlling seasonal reproduction: principles derived from the sheep model and its comparison with hamsters.

PubMed

Weems, Peyton W; Goodman, Robert L; Lehman, Michael N

2015-04-01

Seasonal reproduction is a common adaptive strategy among mammals that allows for breeding to occur at times of the year when it is most advantageous for the subsequent survival and growth of offspring. A major mechanism responsible for seasonal reproduction is a striking increase in the responsiveness of gonadotropin-releasing hormone (GnRH) neurons to the negative feedback effects of estradiol. The neural and neuroendocrine circuitry responsible for mammalian seasonal reproduction has been primarily studied in three animal models: the sheep, and two species of hamsters. In this review, we first describe the afferent signals, neural circuitry and transmitters/peptides responsible for seasonal reproductive transitions in sheep, and then compare these mechanisms with those derived from studies in hamsters. The results suggest common principles as well as differences in the role of specific brain nuclei and neuropeptides, including that of kisspeptin cells of the hypothalamic arcuate nucleus, in regulating seasonal reproduction among mammals. Copyright © 2014 Elsevier Inc. All rights reserved.

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 primary loss or gain of glycosylation function known to exist in these mutant cell lines. Quantitative models of CHO cell glycosylation have the potential for predicting how glycoengineering manipulations might affect glycoform distributions to improve the therapeutic performance of glycoprotein products. PMID:28486471

Enhanced malignant transformation is accompanied by increased survival recovery after ionizing radiation in Chinese hamster embryo fibroblasts

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

Boothman, D.A.

Transformed Chinese hamster embryo fibroblasts (CHEF), which gradually increase in tumor-forming ability in nude mice, were isolated from normal diploid CHEF/18 cells. Transformed CHEF cells (i.e., T30-4 > 21-2M3 > 21-2 > normal CHEF/18) showed gradual increases in potentially lethal damage (PLD) survival recovery. {beta}-Lapachone and camptothecin, modulators of topoisomerase I (Topo I) activity, not only prevented survival recovery in normal as well as in tumor cells, but enhanced unscheduled DNA synthesis. These seemingly conflicting results are due to the fact that Topo I activity can be modulated by inhibitors to convert single-stranded DNA lesions into double-stranded breaks. Increases inmore » unscheduled DNA synthesis may result from a continual supply of free ends, on which DNA repair processes may act. Altering Topo I activity with modulators appears to increase X-ray lethality via a DNA lesion modification suicide pathway. Cells down-regulate Topo I immediately after ionizing radiation to prevent Topo I-mediated lesion modification and to enhance survival recovery. 16 refs., 3 figs., 1 tab.« less

Genotoxicity of corrosion eluates obtained from endosseous implants.

PubMed

Ribeiro, Daniel Araki; Matsumoto, Mariza Akemi; Padovan, Luís Eduardo Marques; Marques, Mariângela Esther Alencar; Salvadori, Daisy Maria Fávero

2007-03-01

Commercially pure titanium alloys are currently used as metallic biomaterials in implantology. Corrosion phenomena appear to play a decisive role in metallic implant long-term behavior. Thus, the goal of this study was to examine the genotoxic potential of corrosion eluates obtained from dental implants using Chinese ovary hamster cells in vitro by the single-cell gel (comet) assay. This technique detects deoxyribonucleic acid strand breaks in individual cells in alkaline conditions. The materials tested included 3 dental implants commercially available. Each of the tested materials was corroded in a solution consisting of equal amounts of acetic acid and sodium chloride (0.1 M) for 1, 3, 7, 14, and 21 days. The Chinese ovary hamster cultures were then exposed to all corrosion eluates obtained from endosseous dental implants for 30 minutes at 37 degrees C. None of the eluates was found to exhibit genotoxicity, regardless of the type of dental implant used. The results suggest that all dental implants tested in this study did not induce deoxyribonucleic acid breakage as depicted by the single-cell gel (comet) assay.

Cytotoxic and mutagenic properties of shale oil byproducts. II. Comparison of mutagenic effects at five genetic markers induced by retort process water plus near ultraviolet light in Chinese hamster ovary cells

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

Chen, D.J.C.; Strniste, G.F.

1982-01-01

A Chinese hamster ovary (CHO) cell line heterozygous at the adenine phosphoribosyl transferase (APRT) locus was used for selection of induced mutants resistant to 8-azaadenine (8AA), 6-thioguanine (6TG), ouabain (OUA), emetine (EMT) and diphtheria toxin (DIP). The expression times necessary for optimizing the number of mutants recovered at the different loci have been determined using the known direct acting mutagen, far ultraviolet light (FUV), and a complex aqueous organic mixture (shale oil process water) activated with near ultraviolet light (NUV). The results indicate that optimal expression times following treatment with either mutagen was between 2 and 8 days. For CHOmore » cells treated with shale oil process water and subsequently exposed to NUV a linear dose response for mutant induction was observed for all five genetic loci. At 10% surviving fraction of cells, between 35- and 130-fold increases above backgound mutation frequencies were observed for the various markers examined.« less

General anesthetic octanol and related compounds activate wild-type and delF508 cystic fibrosis chloride channels

PubMed Central

Marcet, Brice; Becq, Frédéric; Norez, Caroline; Delmas, Patrick; Verrier, Bernard

2004-01-01

Cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel is defective during cystic fibrosis (CF). Activators of the CFTR Cl− channel may be useful for therapy of CF. Here, we demonstrate that a range of general anesthetics like normal-alkanols (n-alkanols) and related compounds can stimulate the Cl− channel activity of wild-type CFTR and delF508-CFTR mutant. The effects of n-alkanols like octanol on CFTR activity were measured by iodide (125I) efflux and patch-clamp techniques on three distinct cellular models: (1) CFTR-expressing Chinese hamster ovary cells, (2) human airway Calu-3 epithelial cells and (3) human airway JME/CF15 epithelial cells which express the delF508-CFTR mutant. Our data show for the first time that n-alkanols activate both wild-type CFTR and delF508-CFTR mutant. Octanol stimulated 125I efflux in a dose-dependent manner in CFTR-expressing cells (wild-type and delF508) but not in cell lines lacking CFTR. 125I efflux and Cl− currents induced by octanol were blocked by glibenclamide but insensitive to 4,4′-diisothiocyanatostilbene-2,2′-disulfonic acid, as expected for a CFTR Cl− current. CFTR activation by octanol was neither due to cell-to-cell uncoupling properties of octanol nor to an intracellular cAMP increase. CFTR activation by octanol requires phosphorylation by protein kinase-A (PKA) since it was prevented by H-89, a PKA inhibitor. n-Alkanols chain length was an important determinant for channel activation, with rank order of potencies: 1-heptanol<1-octanol<2-octanol<1-decanol. Our findings may be of valuable interest for developing novel therapeutic strategies for CF. PMID:14967738

General anesthetic octanol and related compounds activate wild-type and delF508 cystic fibrosis chloride channels.

PubMed

Marcet, Brice; Becq, Frédéric; Norez, Caroline; Delmas, Patrick; Verrier, Bernard

2004-03-01

1. Cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel is defective during cystic fibrosis (CF). Activators of the CFTR Cl(-) channel may be useful for therapy of CF. Here, we demonstrate that a range of general anesthetics like normal-alkanols (n-alkanols) and related compounds can stimulate the Cl(-) channel activity of wild-type CFTR and delF508-CFTR mutant. 2. The effects of n-alkanols like octanol on CFTR activity were measured by iodide ((125)I) efflux and patch-clamp techniques on three distinct cellular models: (1). CFTR-expressing Chinese hamster ovary cells, (2). human airway Calu-3 epithelial cells and (3). human airway JME/CF15 epithelial cells which express the delF508-CFTR mutant. 3. Our data show for the first time that n-alkanols activate both wild-type CFTR and delF508-CFTR mutant. Octanol stimulated (125)I efflux in a dose-dependent manner in CFTR-expressing cells (wild-type and delF508) but not in cell lines lacking CFTR. (125)I efflux and Cl(-) currents induced by octanol were blocked by glibenclamide but insensitive to 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, as expected for a CFTR Cl(-) current. 4. CFTR activation by octanol was neither due to cell-to-cell uncoupling properties of octanol nor to an intracellular cAMP increase. CFTR activation by octanol requires phosphorylation by protein kinase-A (PKA) since it was prevented by H-89, a PKA inhibitor. 5. n-Alkanols chain length was an important determinant for channel activation, with rank order of potencies: 1-heptanol<1-octanol<2-octanol<1-decanol. Our findings may be of valuable interest for developing novel therapeutic strategies for CF.

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.

Detection of early changes in lung cell cytology by flow-systems analysis techniques

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

Steinkamp, J.A.; Hansen, K.M.; Wilson, J.S.

1976-12-01

This report summarizes results of continuing experiments to develop cytological and biochemical indicators for estimating damage to respiratory cells in test animals exposed by inhalation to toxic agents associated with nonnuclear energy production, the specific goal being the application of advanced multiparameter flow-systems technologies to the detection of early atypical cellular changes in lung epithelium. Normal Syrian hamster lung cell samples composed of macrophages, leukocytes, ciliated columnar cells, and epithelial cells were stained with fluorescent dyes specific for different biochemical parameters and were analyzed in liquid suspension as they flowed through a chamber intersecting a laser beam of exciting light.more » Multiple sensors measured the total or two-color fluorescence and light scatter on a cell-by-cell basis. Cellular parameters proportional to optical measurements (i.e., cell size, DNA content, total protein, nonspecific esterase activity, nuclear and cytoplasmic diameters) were displayed as frequency distribution histograms. Lung cell samples were also separated according to various cytological parameters and identified microscopically. The basic operating features of the methodology are discussed briefly, along with specific examples of preliminary results illustrating the initial characterization of exfoliated pulmonary cells from normal hamsters. As the flow technology is adapted further to the analysis of respiratory cells, measurements of changes in physical and biochemical properties as a function of exposure to toxic agents will be performed.« less

Removal of transmissible spongiform encephalopathy prion from large volumes of cell culture media supplemented with fetal bovine serum by using hollow fiber anion-exchange membrane chromatography.

PubMed

Chou, Ming Li; Bailey, Andy; Avory, Tiffany; Tanimoto, Junji; Burnouf, Thierry

2015-01-01

Cases of variant Creutzfeldt-Jakob disease in people who had consumed contaminated meat products from cattle with bovine spongiform encephalopathy emphasize the need for measures aimed at preventing the transmission of the pathogenic prion protein (PrPSc) from materials derived from cattle. Highly stringent scrutiny is required for fetal bovine serum (FBS), a growth-medium supplement used in the production of parenteral vaccines and therapeutic recombinant proteins and in the ex vivo expansion of stem cells for transplantation. One such approach is the implementation of manufacturing steps dedicated to removing PrPSc from materials containing FBS. We evaluated the use of the QyuSpeed D (QSD) adsorbent hollow-fiber anion-exchange chromatographic column (Asahi Kasei Medical, Tokyo, Japan) for the removal of PrPSc from cell culture media supplemented with FBS. We first established that QSD filtration had no adverse effect on the chemical composition of various types of culture media supplemented with 10% FBS or the growth and viability characteristics of human embryonic kidney (HEK293) cells, baby hamster kidney (BHK-21) cells, African green monkey kidney (Vero) cells, and Chinese hamster ovary (CHO-k1) cells propagated in the various culture-medium filtrates. We used a 0.6-mL QSD column for removing PrPSc from up to 1000 mL of Dulbecco's modified Eagle's medium containing 10% FBS previously spiked with the 263K strain of hamster-adapted scrapie. The Western blot analysis, validated alongside an infectivity assay, revealed that the level of PrPSc in the initial 200mL flow-through was reduced by 2.5 to > 3 log10, compared with that of the starting material. These results indicate that QSD filtration removes PrPSc from cell culture media containing 10% FBS, and demonstrate the ease with which QSD filtration can be implemented in at industrial-scale to improve the safety of vaccines, therapeutic recombinant proteins, and ex vivo expanded stem cells produced using growth media supplemented with FBS.

Removal of Transmissible Spongiform Encephalopathy Prion from Large Volumes of Cell Culture Media Supplemented with Fetal Bovine Serum by Using Hollow Fiber Anion-Exchange Membrane Chromatography

PubMed Central

Chou, Ming Li; Bailey, Andy; Avory, Tiffany; Tanimoto, Junji; Burnouf, Thierry

2015-01-01

Cases of variant Creutzfeldt-Jakob disease in people who had consumed contaminated meat products from cattle with bovine spongiform encephalopathy emphasize the need for measures aimed at preventing the transmission of the pathogenic prion protein (PrPSc) from materials derived from cattle. Highly stringent scrutiny is required for fetal bovine serum (FBS), a growth-medium supplement used in the production of parenteral vaccines and therapeutic recombinant proteins and in the ex vivo expansion of stem cells for transplantation. One such approach is the implementation of manufacturing steps dedicated to removing PrPSc from materials containing FBS. We evaluated the use of the QyuSpeed D (QSD) adsorbent hollow-fiber anion-exchange chromatographic column (Asahi Kasei Medical, Tokyo, Japan) for the removal of PrPSc from cell culture media supplemented with FBS. We first established that QSD filtration had no adverse effect on the chemical composition of various types of culture media supplemented with 10% FBS or the growth and viability characteristics of human embryonic kidney (HEK293) cells, baby hamster kidney (BHK-21) cells, African green monkey kidney (Vero) cells, and Chinese hamster ovary (CHO-k1) cells propagated in the various culture-medium filtrates. We used a 0.6-mL QSD column for removing PrPSc from up to 1000 mL of Dulbecco’s modified Eagle’s medium containing 10% FBS previously spiked with the 263K strain of hamster-adapted scrapie. The Western blot analysis, validated alongside an infectivity assay, revealed that the level of PrPSc in the initial 200mL flow-through was reduced by 2.5 to > 3 log10, compared with that of the starting material. These results indicate that QSD filtration removes PrPSc from cell culture media containing 10% FBS, and demonstrate the ease with which QSD filtration can be implemented in at industrial-scale to improve the safety of vaccines, therapeutic recombinant proteins, and ex vivo expanded stem cells produced using growth media supplemented with FBS. PMID:25874629

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.

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

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

A dual reporter cell assay for identifying serotype and drug susceptibility of herpes simplex virus.

PubMed

Lu, Wen-Wen; Sun, Jun-Ren; Wu, Szu-Sian; Lin, Wan-Hsuan; Kung, Szu-Hao

2011-08-15

A dual reporter cell assay (DRCA) that allows real-time detection of herpes simplex virus (HSV) infection was developed. This was achieved by stable transfection of cells with an expression cassette that contains the dual reporter genes, secreted alkaline phosphatase (SEAP) and enhanced green fluorescent protein (EGFP), under the control of an HSV early gene promoter. Baby hamster kidney (BHK) and Chinese hamster ovary (CHO) cell lines were used as parental cell lines because the former is permissive for both HSV serotypes, HSV-1 and HSV-2, whereas the latter is susceptible to infection only by HSV-2. The DRCA permitted differential detection of HSV-1 and HSV-2 by observation of EGFP-positive cells, as substantiated by screening a total of 35 samples. The BHK-based cell line is sensitive to a viral titer as low as a single plaque-forming unit with a robust assay window as measured by a chemiluminescent assay. Evaluations of the DRCA with representative acyclovir-sensitive and acyclovir-resistant HSV strains demonstrated that their drug susceptibilities were accurately determined by a 48-h format. In summary, this novel DRCA is a useful means for serotyping of HSV in real time as well as a rapid screening method for determining anti-HSV susceptibilities. Copyright © 2011 Elsevier Inc. All rights reserved.

Genetic analysis of tumorigenesis: XXXII. Localization of constitutionally amplified KRAS sequences to Chinese hamster chromosomes X and Y by in situ hybridization.

PubMed

Stenman, G; Anisowicz, A; Sager, R

1988-11-01

The KRAS gene is constitutionally amplified in the Chinese hamster. We have mapped the amplified sequences by in situ hybridization to two major sites on the X and Y chromosomes, Xq4 and Yp2. No autosomal site was detected despite a search under relaxed hybridization conditions. KRAS DNA is amplified about 50-fold compared to a human cell line known to have a diploid number of KRAS sequences, whereas mRNA expression is 5- to 10-fold lower than in normal human cells. While mRNA expression levels do not necessarily parallel gene copy number, the low expression level strongly suggests that the amplified sequences are transcriptionally silent. It is suggested that the amplified sequences arose from the original KRAS gene on chromosome 8 and that the KRAS sequences on the Y chromosome arose by X-Y recombination.

Modeling Severe Fever with Thrombocytopenia Syndrome Virus Infection in Golden Syrian Hamsters: Importance of STAT2 in Preventing Disease and Effective Treatment with Favipiravir

PubMed Central

Westover, Jonna B.; Miao, Jinxin; Van Wettere, Arnaud J.; Rigas, Johanna D.; Hickerson, Brady T.; Jung, Kie-Hoon; Li, Rong; Conrad, Bettina L.; Nielson, Skot; Furuta, Yousuke; Wang, Zhongde

2016-01-01

ABSTRACT Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease endemic in parts of Asia. The etiologic agent, SFTS virus (SFTSV; family Bunyaviridae, genus Phlebovirus) has caused significant morbidity and mortality in China, South Korea, and Japan, with key features of disease being intense fever, thrombocytopenia, and leukopenia. Case fatality rates are estimated to be in the 30% range, and no antivirals or vaccines are approved for use for treatment and prevention of SFTS. There is evidence that in human cells, SFTSV sequesters STAT proteins in replication complexes, thereby inhibiting type I interferon signaling. Here, we demonstrate that hamsters devoid of functional STAT2 are highly susceptible to as few as 10 PFU of SFTSV, with animals generally succumbing within 5 to 6 days after subcutaneous challenge. The disease included marked thrombocytopenia and inflammatory disease characteristic of the condition in humans. Infectious virus titers were present in the blood and most tissues 3 days after virus challenge, and severe inflammatory lesions were found in the spleen and liver samples of SFTSV-infected hamsters. We also show that SFTSV infection in STAT2 knockout (KO) hamsters is responsive to favipiravir treatment, which protected all animals from lethal disease and reduced serum and tissue viral loads by 3 to 6 orders of magnitude. Taken together, our results provide additional insights into the pathogenesis of SFTSV infection and support the use of the newly described STAT2 KO hamster model for evaluation of promising antiviral therapies. IMPORTANCE Severe fever with thrombocytopenia syndrome (SFTS) is an emerging viral disease for which there are currently no therapeutic options or available vaccines. The causative agent, SFTS virus (SFTSV), is present in China, South Korea, and Japan, and infections requiring medical attention result in death in as many as 30% of the cases. Here, we describe a novel model of SFTS in hamsters genetically engineered to be deficient in a protein that helps protect humans and animals against viral infections. These hamsters were found to be susceptible to SFTSV and share disease features associated with the disease in humans. Importantly, we also show that SFTSV infection in hamsters can be effectively treated with a broad-spectrum antiviral drug approved for use in Japan. Our findings suggest that the new SFTS model will be an excellent resource to better understand SFTSV infection and disease as well as a valuable tool for evaluating promising antiviral drugs. PMID:27881648

Modeling Severe Fever with Thrombocytopenia Syndrome Virus Infection in Golden Syrian Hamsters: Importance of STAT2 in Preventing Disease and Effective Treatment with Favipiravir.

PubMed

Gowen, Brian B; Westover, Jonna B; Miao, Jinxin; Van Wettere, Arnaud J; Rigas, Johanna D; Hickerson, Brady T; Jung, Kie-Hoon; Li, Rong; Conrad, Bettina L; Nielson, Skot; Furuta, Yousuke; Wang, Zhongde

2017-02-01

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease endemic in parts of Asia. The etiologic agent, SFTS virus (SFTSV; family Bunyaviridae, genus Phlebovirus) has caused significant morbidity and mortality in China, South Korea, and Japan, with key features of disease being intense fever, thrombocytopenia, and leukopenia. Case fatality rates are estimated to be in the 30% range, and no antivirals or vaccines are approved for use for treatment and prevention of SFTS. There is evidence that in human cells, SFTSV sequesters STAT proteins in replication complexes, thereby inhibiting type I interferon signaling. Here, we demonstrate that hamsters devoid of functional STAT2 are highly susceptible to as few as 10 PFU of SFTSV, with animals generally succumbing within 5 to 6 days after subcutaneous challenge. The disease included marked thrombocytopenia and inflammatory disease characteristic of the condition in humans. Infectious virus titers were present in the blood and most tissues 3 days after virus challenge, and severe inflammatory lesions were found in the spleen and liver samples of SFTSV-infected hamsters. We also show that SFTSV infection in STAT2 knockout (KO) hamsters is responsive to favipiravir treatment, which protected all animals from lethal disease and reduced serum and tissue viral loads by 3 to 6 orders of magnitude. Taken together, our results provide additional insights into the pathogenesis of SFTSV infection and support the use of the newly described STAT2 KO hamster model for evaluation of promising antiviral therapies. Severe fever with thrombocytopenia syndrome (SFTS) is an emerging viral disease for which there are currently no therapeutic options or available vaccines. The causative agent, SFTS virus (SFTSV), is present in China, South Korea, and Japan, and infections requiring medical attention result in death in as many as 30% of the cases. Here, we describe a novel model of SFTS in hamsters genetically engineered to be deficient in a protein that helps protect humans and animals against viral infections. These hamsters were found to be susceptible to SFTSV and share disease features associated with the disease in humans. Importantly, we also show that SFTSV infection in hamsters can be effectively treated with a broad-spectrum antiviral drug approved for use in Japan. Our findings suggest that the new SFTS model will be an excellent resource to better understand SFTSV infection and disease as well as a valuable tool for evaluating promising antiviral drugs. Copyright © 2017 American Society for Microbiology.

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.

Effects of transplanted circulating endothelial progenitor cells and platelet microparticles in atherosclerosis development.

PubMed

Georgescu, Adriana; Alexandru, Nicoleta; Andrei, Eugen; Dragan, Emanuel; Cochior, Daniel; Dias, Sérgio

2016-08-01

Atherosclerosis is an inflammatory disease, in which risk factors such as hyperlipidemia and hypertension affect the arterial endothelium, resulting in dysfunction, cell damage or both. The number of circulating endothelial progenitor cells and microparticles provides invaluable outcome prediction for atherosclerosis disease. However, evidence for the therapeutic potential of endothelial progenitor cells and microparticles in atherosclerosis development is limited. Our study was designed to investigate the possible protective role of a cell therapy-based approach, using endothelial progenitor cells and the dual behaviour of circulating platelet microparticles, on atherosclerosis development in hypertensive-hypercholesterolemic hamster model. Consequently, control hamsters received four intravenous inoculations of: (1) 1×10(5) endothelial progenitor cells of healthy origins in one dose per month, during four months of diet-induced atherosclerosis, and after hypertensive-hypercholesterolemic diet for further four months; (2) in a second set of experiments, 1×10(5) endothelial progenitor cells of healthy origins or/and 1×10(5) platelet microparticles of atherosclerotic origins were inoculated every other month during hypertensive-hypercholesterolemic diet. Endothelial progenitor cell treatment had the following effects: (1) re-established plasmatic parameters: cholesterol and triglyceride concentrations, blood pressure, heart rate, cytokine and chemokine profiles, platelet microparticle pro-thrombotic activity and endothelial progenitor cell paracrine activity reflected by cytokine/chemokine detection; (2) reduced lipid, macrophage and microparticle accumulation in liver; (3) reduced atherosclerosis development, revealed by decreased lipid, macrophage and microparticle content of arterial wall; (4) induced the recruitment and incorporation of endothelial progenitor cells into liver and arterial wall; (5) improved arterial dysfunction by increasing contraction and relaxation; (6) reduced the protein expression of specific pro-inflammatory molecules in liver and arterial wall. Platelet microparticle transplantation aggravated the above-mentioned biomarkers and atherosclerosis process, which were partially reverted with co-inoculation of platelet microparticles and endothelial progenitor cells. With this study, we demonstrate in a hypertensive-hypercholesterolemic hamster model, that the endothelial progenitor cell-based therapy suppresses the development of atherosclerosis and reduces hepatic lipid and macrophage accumulation with the consequent alleviation of dyslipidaemia and hypertension. Our results support the notion that increasing the number of circulating endothelial progenitor cells by different ways could be a promising therapeutic tool for atherosclerosis. © 2016 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.

Monosodium glutamate-induced arcuate nucleus damage affects both natural torpor and 2DG-induced torpor-like hypothermia in Siberian hamsters.

PubMed

Pelz, Kimberly M; Routman, David; Driscoll, Joseph R; Kriegsfeld, Lance J; Dark, John

2008-01-01

Siberian hamsters (Phodopus sungorus) have the ability to express daily torpor and decrease their body temperature to approximately 15 degrees C, providing a significant savings in energy expenditure. Daily torpor in hamsters is cued by winterlike photoperiods and occurs coincident with the annual nadirs in body fat reserves and chronic leptin concentrations. To better understand the neural mechanisms underlying torpor, Siberian hamster pups were postnatally treated with saline or MSG to ablate arcuate nucleus neurons that likely possess leptin receptors. Body temperature was studied telemetrically in cold-acclimated (10 degrees C) male and female hamsters moved to a winterlike photoperiod (10:14-h light-dark cycle) (experiments 1 and 2) or that remained in a summerlike photoperiod (14:10-h light-dark cycle) (experiment 3). In experiment 1, even though other photoperiodic responses persisted, MSG-induced arcuate nucleus ablations prevented the photoperiod-dependent torpor observed in saline-treated Siberian hamsters. MSG-treated hamsters tended to possess greater fat reserves. To determine whether reductions in body fat would increase frequency of photoperiod-induced torpor after MSG treatment, hamsters underwent 2 wk of food restriction (70% of ad libitum) in experiment 2. Although food restriction did increase the frequency of torpor in both MSG- and saline-treated hamsters, it failed to normalize the proportion of MSG-treated hamsters undergoing photoperiod-dependent torpor. In experiment 3, postnatal MSG treatments reduced the proportion of hamsters entering 2DG-induced torpor-like hypothermia by approximately 50% compared with saline-treated hamsters (38 vs. 72%). In those MSG-treated hamsters that did become hypothermic, their minimum temperature during hypothermia was significantly greater than comparable saline-treated hamsters. We conclude that 1) arcuate nucleus mechanisms mediate photoperiod-induced torpor, 2) food-restriction-induced torpor may also be reduced by MSG treatments, and 3) arcuate nucleus neurons make an important, albeit partial, contribution to 2DG-induced torpor-like hypothermia.

Regulation of Glutathione in a Rat Diploid Hepatic Epithelial Cell Line

DTIC Science & Technology

1990-06-01

supporting the contention that they are not pre-neoplastic (60). Metabolic cooperation by gap- junctional intercellular communication has been demonstrated...counted. The resulting population statistics allowed calculation and display of cycle-specific cell characteristics and compartment transit times (see...was repeated in chinese hamster V79 cells to see if the effect is idiosyncratic. It is not - V79 cells respond to CYC in the same fashion as WB344(s) if

Cytologic Effects of Air Force Chemicals

DTIC Science & Technology

1980-11-01

Studies of DNA replication and repair in cell cultures have shown that hydrazine, although highly toxic to cells, does not damage DNA and thus...interfere directly with DNA replication in Chinese hamster ovary cells grown in vitro, nor does it affect DNA repair synthesis in CCL-185 human lung cells...vitro with chemicals and monitoring their effect on DNA replication and repair. This method has been used to show that the alkylating agents MMS and 4

In-vivo monitoring of development of cholangiocarcinoma induced with C. sinensis and N-nitrosodimethylamine in Syrian golen hamsters using ultrasonography and magnetic resonance imaging: a preliminary study.

PubMed

Woo, Hyunsik; Han, Joon Koo; Kim, Jung Hoon; Hong, Sung-Tae; Uddin, Md Hafiz; Jang, Ja-June

2017-04-01

The purpose of this study is to evaluate high-resolution ultrasound and magnetic resonance imaging (MRI) in monitoring of cholangiocarcinoma in the hamsters with C. sinensis infection and N-nitrosodimethylamine (NDMA). Twenty-four male Syrian golden hamsters of were divided into four groups composed of five hamsters as control, five hamsters receiving 30 metacercariae of C. sinensis per each hamster, five hamsters receiving NDMA in drinking water, and nine hamsters receiving both metacercariae and NDMA. Ultrasound was performed every other week from baseline to the 12th week of infection. MRI and histopathologic examination was done from the 4th week to 12th week. Cholangiocarcinomas appeared as early as the 6th week of infection. There were 12 cholangiocarcinomas, nine and ten of which were demonstrated by ultrasound and MRI, respectively. Ultrasound and MRI findings of cholangiocarcinomas in the hamsters were similar to those of the mass-forming intrahepatic cholangiocarcinomas in humans. Ultrasound and MRI also showed other findings of disease progression such as periductal increased echogenicity or signal intensity, ductal dilatation, complicated cysts, and sludges in the gallbladder. High-resolution ultrasound and MRI can monitor and detect the occurrence of cholangiocarcinoma in the hamsters non-invasively. • High-resolution ultrasound and MRI can monitor occurrence of cholangiocarcinoma in the hamsters. • Cholangiocarcinomas were detected as early as the 6th week after C. sinensis infection. • Axial T2-weighted MRI demonstrated cholangiocarcinomas and various inflammatory findings in the hamsters.

Cytokine and Chemokine Expression in Kidneys during Chronic Leptospirosis in Reservoir and Susceptible Animal Models

PubMed Central

Matsui, Mariko; Roche, Louise; Geroult, Sophie; Soupé-Gilbert, Marie-Estelle; Monchy, Didier; Huerre, Michel; Goarant, Cyrille

2016-01-01

Leptospirosis is caused by pathogenic spirochetes of the genus Leptospira. Humans can be infected after exposure to contaminated urine of reservoir animals, usually rodents, regarded as typical asymptomatic carriers of leptospires. In contrast, accidental hosts may present an acute form of leptospirosis with a range of clinical symptoms including the development of Acute Kidney Injury (AKI). Chronic Kidney Disease (CKD) is considered as a possible AKI-residual sequela but little is known about the renal pathophysiology consequent to leptospirosis infection. Herein, we studied the renal morphological alterations in relation with the regulation of inflammatory cytokines and chemokines, comparing two experimental models of chronic leptospirosis, the golden Syrian hamster that survived the infection, becoming carrier of virulent leptospires, and the OF1 mouse, a usual reservoir of the bacteria. Animals were monitored until 28 days after injection with a virulent L. borgpetersenii serogroup Ballum to assess chronic infection. Hamsters developed morphological alterations in the kidneys with tubulointerstitial nephritis and fibrosis. Grading of lesions revealed higher scores in hamsters compared to the slight alterations observed in the mouse kidneys, irrespective of the bacterial load. Interestingly, pro-fibrotic TGF-β was downregulated in mouse kidneys. Moreover, cytokines IL-1β and IL-10, and chemokines MIP-1α/CCL3 and IP-10/CXCL-10 were significantly upregulated in hamster kidneys compared to mice. These results suggest a possible maintenance of inflammatory processes in the hamster kidneys with the infiltration of inflammatory cells in response to bacterial carriage, resulting in alterations of renal tissues. In contrast, lower expression levels in mouse kidneys indicated a better regulation of the inflammatory response and possible resolution processes likely related to resistance mechanisms. PMID:27219334

Comparison of the pathogenicity of Nipah virus isolates from Bangladesh and Malaysia in the Syrian hamster.

PubMed

DeBuysscher, Blair L; de Wit, Emmie; Munster, Vincent J; Scott, Dana; Feldmann, Heinz; Prescott, Joseph

2013-01-01

Nipah virus is a zoonotic pathogen that causes severe disease in humans. The mechanisms of pathogenesis are not well described. The first Nipah virus outbreak occurred in Malaysia, where human disease had a strong neurological component. Subsequent outbreaks have occurred in Bangladesh and India and transmission and disease processes in these outbreaks appear to be different from those of the Malaysian outbreak. Until this point, virtually all Nipah virus studies in vitro and in vivo, including vaccine and pathogenesis studies, have utilized a virus isolate from the original Malaysian outbreak (NiV-M). To investigate potential differences between NiV-M and a Nipah virus isolate from Bangladesh (NiV-B), we compared NiV-M and NiV-B infection in vitro and in vivo. In hamster kidney cells, NiV-M-infection resulted in extensive syncytia formation and cytopathic effects, whereas NiV-B-infection resulted in little to no morphological changes. In vivo, NiV-M-infected Syrian hamsters had accelerated virus replication, pathology and death when compared to NiV-B-infected animals. NiV-M infection also resulted in the activation of host immune response genes at an earlier time point. Pathogenicity was not only a result of direct effects of virus replication, but likely also had an immunopathogenic component. The differences observed between NiV-M and NiV-B pathogeneis in hamsters may relate to differences observed in human cases. Characterization of the hamster model for NiV-B infection allows for further research of the strain of Nipah virus responsible for the more recent outbreaks in humans. This model can be used to study NiV-B pathogenesis, transmission, and countermeasures that could be used to control outbreaks.

Comparison of the Pathogenicity of Nipah Virus Isolates from Bangladesh and Malaysia in the Syrian Hamster

PubMed Central

DeBuysscher, Blair L.; de Wit, Emmie; Munster, Vincent J.; Scott, Dana; Feldmann, Heinz; Prescott, Joseph

2013-01-01

Nipah virus is a zoonotic pathogen that causes severe disease in humans. The mechanisms of pathogenesis are not well described. The first Nipah virus outbreak occurred in Malaysia, where human disease had a strong neurological component. Subsequent outbreaks have occurred in Bangladesh and India and transmission and disease processes in these outbreaks appear to be different from those of the Malaysian outbreak. Until this point, virtually all Nipah virus studies in vitro and in vivo, including vaccine and pathogenesis studies, have utilized a virus isolate from the original Malaysian outbreak (NiV-M). To investigate potential differences between NiV-M and a Nipah virus isolate from Bangladesh (NiV-B), we compared NiV-M and NiV-B infection in vitro and in vivo. In hamster kidney cells, NiV-M-infection resulted in extensive syncytia formation and cytopathic effects, whereas NiV-B-infection resulted in little to no morphological changes. In vivo, NiV-M-infected Syrian hamsters had accelerated virus replication, pathology and death when compared to NiV-B-infected animals. NiV-M infection also resulted in the activation of host immune response genes at an earlier time point. Pathogenicity was not only a result of direct effects of virus replication, but likely also had an immunopathogenic component. The differences observed between NiV-M and NiV-B pathogeneis in hamsters may relate to differences observed in human cases. Characterization of the hamster model for NiV-B infection allows for further research of the strain of Nipah virus responsible for the more recent outbreaks in humans. This model can be used to study NiV-B pathogenesis, transmission, and countermeasures that could be used to control outbreaks. PMID:23342177

Cathinone increases body temperature, enhances locomotor activity, and induces striatal c-fos expression in the Siberian hamster.

PubMed

Jones, S; Fileccia, E L; Murphy, M; Fowler, M J; King, M V; Shortall, S E; Wigmore, P M; Green, A R; Fone, K C F; Ebling, F J P

2014-01-24

Cathinone is a β-keto alkaloid that is the major active constituent of khat, the leaf of the Catha edulis plant that is chewed recreationally in East Africa and the Middle East. Related compounds, such as methcathinone and mephedrone have been increasing in popularity as recreational drugs, resulting in the recent proposal to classify khat as a Class C drug in the UK. There is still limited knowledge of the pharmacological effects of cathinone. This study examined the acute effects of cathinone on core body temperature, locomotor and other behaviors, and neuronal activity in Siberian hamsters. Adult male hamsters, previously implanted with radio telemetry devices, were treated with cathinone (2 or 5mg/kg i.p.), the behavioral profile scored and core body temperature and locomotor activity recorded by radio telemetry. At the end of the study, hamsters received vehicle or cathinone (5mg/kg) and neuronal activation in the brain was determined using immunohistochemical evaluation of c-fos expression. Cathinone dose-dependently induced significant (p<0.0001) increases in both temperature and locomotor activity lasting 60-90min. Cathinone (2mg/kg) increased rearing (p<0.02), and 5mg/kg increased both rearing (p<0.001) and lateral head twitches (p<0.02). Both cathinone doses decreased the time spent at rest (p<0.001). The number of c-fos immunopositive cells were significantly increased in the striatum (p<0.0001) and suprachiasmatic nucleus (p<0.05) following cathinone, indicating increased neuronal activity. There was no effect of cathinone on food intake or body weight. It is concluded that systemic administration of cathinone induces significant behavioral changes and CNS activation in the hamster. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Development of a bifunctional filter for prion protein and leukoreduction of red blood cell components.

PubMed

Yokomizo, Tomo; Kai, Takako; Miura, Morikazu; Ohto, Hitoshi

2015-02-01

Leukofiltration of blood components is currently implemented worldwide as a precautionary measure against white blood cell-associated adverse effects and the potential transmission of variant Creutzfeldt-Jakob disease (vCJD). A newly developed bifunctional filter (Sepacell Prima, Asahi Kasei Medical) was assessed for prion removal, leukoreduction (LR), and whether the filter significantly affected red blood cells (RBCs). Sepacell Prima's postfiltration effects on RBCs, including hemolysis, complement activation, and RBC chemistry, were compared with those of a conventional LR filter (Sepacell Pure RC). Prion removal was measured by Western blot after spiking RBCs with microsomal fractions derived from scrapie-infected hamster brain homogenate. Serially diluted exogenous prion solutions (0.05 mL), with or without filtration, were injected intracerebrally into Golden Syrian hamsters. LR efficiency of 4.44 log with the Sepacell Prima was comparable to 4.11 log with the conventional LR filter. There were no significant differences between the two filters in hemoglobin loss, hemolysis, complement activation, and RBC biomarkers. In vitro reduction of exogenously spiked prions by the filter exceeded 3 log. The titer, 6.63 (log ID50 /mL), of prefiltration infectivity of healthy hamsters was reduced to 2.52 (log ID50 /mL) after filtration. The reduction factor was calculated as 4.20 (log ID50 ). With confirmed removal efficacy for exogenous prion protein, this new bifunctional prion and LR filter should reduce the residual risk of vCJD transmission through blood transfusion without adding complexity to component processing. © 2014 AABB.

Single Amino Acid Residue in the A2 Domain of Major Histocompatibility Complex Class I Is Involved in the Efficiency of Equine Herpesvirus-1 Entry*

PubMed Central

Sasaki, Michihito; Kim, Eunmi; Igarashi, Manabu; Ito, Kimihito; Hasebe, Rie; Fukushi, Hideto; Sawa, Hirofumi; Kimura, Takashi

2011-01-01

Equine herpesvirus-1 (EHV-1), an α-herpesvirus of the family Herpesviridae, causes respiratory disease, abortion, and encephalomyelitis in horses. EHV-1 utilizes equine MHC class I molecules as entry receptors. However, hamster MHC class I molecules on EHV-1-susceptible CHO-K1 cells play no role in EHV-1 entry. To identify the MHC class I molecule region that is responsible for EHV-1 entry, domain exchange and site-directed mutagenesis experiments were performed, in which parts of the extracellular region of hamster MHC class I (clone C5) were replaced with corresponding sequences from equine MHC class I (clone A68). Substitution of alanine for glutamine at position 173 (Q173A) within the α2 domain of the MHC class I molecule enabled hamster MHC class I C5 to mediate EHV-1 entry into cells. Conversely, substitution of glutamine for alanine at position 173 (A173Q) in equine MHC class I A68 resulted in loss of EHV-1 receptor function. Equine MHC class I clone 3.4, which possesses threonine at position 173, was unable to act as an EHV-1 receptor. Substitution of alanine for threonine at position 173 (T173A) enabled MHC class I 3.4 to mediate EHV-1 entry into cells. These results suggest that the amino acid residue at position 173 of the MHC class I molecule is involved in the efficiency of EHV-1 entry. PMID:21949188

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.

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.

Detection of extracellular neutrophil elastase in hamster lungs after intratracheal instillation of E. coli lipopolysaccharide using a fluorogenic, elastase-specific, synthetic substrate.

PubMed Central

Rudolphus, A.; Stolk, J.; van Twisk, C.; van Noorden, C. J.; Dijkman, J. H.; Kramps, J. A.

1992-01-01

Repeated intratracheal instillations of E. coli lipopolysaccharide (LPS) in hamster lungs cause an influx of polymorphonuclear leukocytes (PMNs) into the alveolar walls, with concomitant development of severe emphysema. It has been suggested that elastase, released by these PMNs, is involved in the development of emphysema. This study demonstrates the release of elastase from recruited PMNs in cryostat sections of hamster lungs, after being treated once, twice, or thrice with LPS, intratracheally. Elastase activity was visualized using two elastase-specific synthetic substrates, to which a methoxynaphthylamine (MNA) group had been bound covalently. Liberated MNA, when made insoluble by coupling with 5-nitrosalicylaldehyde, fluoresces strongly. The authors observed that the interval between start of incubation and appearance of fluorescence and the intensity of fluorescence correlated with the number of LPS administrations. Fluorescence was observed to be located in or in close vicinity to alveolar walls. No fluorescence was observed in sections of untreated hamsters. Liberation of MNA from synthetic substrates was delayed strongly by the addition of a recombinant secretory leukocyte proteinase inhibitor or a substituted cephalosporin neutrophil elastase inhibitor. The authors conclude that LPS-mediated PMN influx into the lung is accompanied by release of elastase from these cells and speculate that this PMN-elastase is involved in the development of LPS-mediated emphysema. Images Figure 1 Figure 2 Figure 3 PMID:1632460

Anti-inflammatory and anti-periductal fibrosis effects of an anthocyanin complex in Opisthorchis viverrini-infected hamsters.

PubMed

Intuyod, Kitti; Priprem, Aroonsri; Limphirat, Wanwisa; Charoensuk, Lakhanawan; Pinlaor, Porntip; Pairojkul, Chawalit; Lertrat, Kamol; Pinlaor, Somchai

2014-12-01

The pharmacological activities of herbal extracts can be enhanced by complex formation. In this study, we manipulated cyanidin and delphinidin-rich extracts to form an anthocyanin complex (AC) with turmeric and evaluated activity against inflammation and periductal fibrosis in Opisthorchis viverrini-infected hamsters. The AC was prepared from anthocyanins extracted from cobs of purple waxy corn (70%), petals of blue butterfly pea (20%) and turmeric extract (10%), resulting in an enhanced free-radical scavenging capacity. Oral administration of AC (175 and 700 mg/kg body weight) every day for 1 month to O. viverrini-infected hamsters resulted in reduced inflammatory cells and periductal fibrosis. Fourier transform infrared spectroscopy and partial least square discriminant analysis suggested nucleic acid changes in the O. viverrini-infected liver samples, which were partially prevented by the AC treatment. AC reduced 8-oxodG formation, an oxidative DNA damage marker, significantly decreased levels of nitrite in the plasma and alanine aminotransferase activity and increased the ferric reducing ability of plasma. AC also decreased the expression of oxidant-related genes (NF-κB and iNOS) and increased the expression of antioxidant-related genes (CAT, SOD, and GPx). Thus, AC increases free-radical scavenging capacity, decreases inflammation, suppresses oxidative/nitrative stress, and reduces liver injury and periductal fibrosis in O. viverrini-infected hamsters.

Visual pigment coexpression in all cones of two rodents, the Siberian hamster, and the pouched mouse.

PubMed

Lukáts, Akos; Dkhissi-Benyahya, Ouria; Szepessy, Zsuzsanna; Röhlich, Pál; Vígh, Béla; Bennett, Nigel C; Cooper, Howard M; Szél, Agoston

2002-07-01

To decide whether the identical topography of short- and middle-wavelength cone photoreceptors in two species of rodents reflects the presence of both opsins in all cone cells. Double-label immunocytochemistry using antibodies directed against short-wavelength (S)-and middle- to long-wavelength (M/L)-sensitive opsin were used to determine the presence of visual pigments in cones of two species of rodents, the Siberian hamster (Phodopus sungorus) and the pouched mouse (Saccostomus campestris) from South Africa. Topographical distribution was determined from retinal whole-mounts, and the colocalization of visual pigments was examined using confocal laser scanning microscopy. Opsin colocalization was also confirmed in consecutive semithin tangential sections. The immunocytochemical results demonstrate that in both the Siberian hamster and the pouched mouse all retinal cones contain two visual pigments. No dorsoventral gradient in the differential expression of the two opsins is observed. The retina of the Siberian hamster and the pouched mouse is the first example to show a uniform coexpression of M and S cone opsins in all cones, without any topographical gradient in opsin expression. This finding makes these two species good models for the study of molecular control mechanisms in opsin coexpression in rodents, and renders them suitable as sources of dual cones for future investigations on the role and neural connections of this cone type.

Inactivated yellow fever 17D vaccine: development and nonclinical safety, immunogenicity and protective activity.

PubMed

Monath, Thomas P; Lee, Cynthia K; Julander, Justin G; Brown, Alicja; Beasley, David W; Watts, Douglas M; Hayman, Edward; Guertin, Patrick; Makowiecki, Joseph; Crowell, Joseph; Levesque, Philip; Bowick, Gavin C; Morin, Merribeth; Fowler, Elizabeth; Trent, Dennis W

2010-05-14

In the last 10 years new concerns have arisen about safety of the live, attenuated yellow fever (YF) 17D vaccine, in particular viscerotropic adverse events, which have a case-fatality rate of 64%. A non-replicating cell culture-based vaccine would not cause these adverse events, and potentially could be used in persons with precautions or contraindications to use of the live vaccine, including age <9 months and >60 years, egg allergy, immune suppression, and pregnancy. We developed a whole virion vaccine from the 17D strain inactivated with beta-propiolactone, and adsorbed to aluminum hydroxide. The inactivated vaccine was highly immunogenic in mice, hamsters, and cynomolgus macaques. After a single dose in hamsters and macaques, neutralizing antibody titers were similar to those elicited by the live 17D vaccine (YF-VAX, Sanofi Pasteur). After two doses of inactivated vaccine, neutralizing antibody titers in hamsters were significantly higher than after a single dose of YF-VAX [geometric mean titer (GMT) 20,480 vs. 1940, respectively (P<0.001, ANOVA)]. Hamsters given a single dose or two doses of inactivated vaccine or a single dose of YF-VAX were fully protected against hepatitis, viremia, weight loss and death after challenge with YF virus (Jimenez strain). A clinical trial of the inactivated vaccine (XRX-001) has been initiated. Copyright 2010 Elsevier Ltd. All rights reserved.

Binding-, intracellular transport-, and biosynthesis-defective mutants of vasopressin type 2 receptor in patients with X-linked nephrogenic diabetes insipidus.

PubMed Central

Tsukaguchi, H; Matsubara, H; Taketani, S; Mori, Y; Seido, T; Inada, M

1995-01-01

Nephrogenic diabetes insipidus (NDI) is most often an X-linked disorder in which urine is not concentrated due to renal resistance to arginine vasopressin. We recently identified four vasopressin type 2 receptor gene mutations in unrelated X-linked NDI families, including R143P, delta V278, R202C, and 804insG. All these mutations reduced ligand binding activity to < 10% of the normal without affecting mRNA accumulation. To elucidate whether the receptors are expressed on the cell surface, we analyzed biosynthesis and localization of tagged or untagged receptors stably expressed in Chinese hamster ovary (CHO) cells, using two antibodies directed against distinct termini. Whole-cell and surface labeling studies revealed that the R202C clone had both surface-localized (50-55 kD) and intracellular proteins (40 and 75 kD), similar to the wild-type AVPR2 clone, whereas the R143P and delta V278 clones lacked the surface receptors, despite relatively increased intracellular components. The 804insG mutant cell produced no proteins despite an adequate mRNA level. Immunofluorescence staining confirmed that the R202C mutant reaches the cell surface, whereas the R143P and delta V278 mutants are retained within the cytoplasmic compartment. Thus, R202C, R143P/delta V278, and 804insG result in three distinct phenotypes, that is, a simple binding impairment at the cell surface, blocked intracellular transport, and ineffective biosynthesis or/and accelerated degradation of the receptor, respectively, and therefore are responsible for NDI. This phenotypic classification will help understanding of molecular pathophysiology of this disorder. Images PMID:7560098

Lectin histochemistry as a tool to identify apoptotic cells in the seminiferous epithelium of Syrian hamster (Mesocricetus auratus) subjected to short photoperiod.

PubMed

Seco-Rovira, V; Beltrán-Frutos, E; Ferrer, C; Sánchez-Huertas, M M; Madrid, J F; Saez, F J; Pastor, L M

2013-12-01

Lectins have been widely used to study the pattern of cellular glycoconjugates in numerous species. In the process of cellular apoptosis, it has been observed that changes occur in the membrane sugar sequences of these apoptotic cells. The aim of our work was to identify which lectins, out of an extensive battery of the same (PNA, SBA, HPA, LTA, Con-A, UEA-I, WGA, DBA, MAA, GNA, AAA, SNA), show affinity for germinal cells in apoptosis, at what stage of cell death they do so and in which germinal cell types they can be detected. For this, we studied testis sections during testicular regression in Syrian hamster (Mesocricetus auratus) subjected to short photoperiod. Several lectins showed an affinity for the glycoconjugate residues of germ cells in apoptosis: Gal β1,3-GalNAcα1, α-d-mannose, N-acetylgalactosamine and l-fucose. Furthermore, lectin specificity was observed for some specific germinal cells and in certain stages of apoptosis. It was also observed that one of these lectins (PNA) showed affinity for Sertoli cells undergoing apoptosis. Therefore, we conclude that the use of lectin histochemistry could be a very useful tool for studying apoptosis in the seminiferous epithelium because of the specificity shown towards germinal cells in pathological or experimentally induced epithelial depletion models. © 2013 Blackwell Verlag GmbH.

Comparative ultrastructure of vallate, foliate and fungiform taste buds of golden Syrian hamster.

PubMed

Miller, R L; Chaudhry, A P

1976-01-01

A fine-structure study of the hamster fungiform, foliate and vallate taste buds was undertaken for comparative purposes. All three taste bud types shared in common composition of the dark cells, light cells, basal cells, nerve fibers and nerve endings and undifferentiated peripheral cells, but morphological difference existed among them. The foliate and vallate taste buds were quite similar in their ultrastructural morphology. Their dark cells displayed long apical necks, long apical microvilli, apical osmiophilic secretory granules and an abundant rough endoplasmic reticulum. The dark cells of the fungiform taste buds, however, showed no neck formation and lacked apical osmiophilic granules. They had short apical microvilli and relatively scant rough endoplasmic reticulum. There was no difference in the fine structure features of the light cells, basal cells and neural elements of different types of taste buds. Both light and dark cells were much more readily distinguishable in foliate and vallate buds than in fungiform buds at both light-and electron-microscopic levels. Foliate and vallate buds demonstrated homogeneous dense substance within the taste pores while fungiform pores were frequently empty. It is speculated that the differences in taste bud morphology may be due to their different lingual locations and/or may be a reflection of the differences in the inductive influences from different nerves. Furthermore, structural differences may be responsible for varying thresholds to different taste modalities.

Photoperiodic regulation of cellular retinol binding protein, CRBP1 [corrected] and nestin in tanycytes of the third ventricle ependymal layer of the Siberian hamster.

PubMed

Barrett, Perry; Ivanova, Elena; Graham, E Scott; Ross, Alexander W; Wilson, Dana; Plé, Helene; Mercer, Julian G; Ebling, Francis J; Schuhler, Sandrine; Dupré, Sandrine M; Loudon, Andrew; Morgan, Peter J

2006-12-01

Tanycytes in the ependymal layer of the third ventricle act both as a barrier and a communication gateway between the cerebrospinal fluid, brain and portal blood supply to the pituitary gland. However, the range, importance and mechanisms involved in the function of tanycytes remain to be explored. In this study, we have utilized a photoperiodic animal to examine the expression of three unrelated gene sequences in relation to photoperiod-induced changes in seasonal physiology and behaviour. We demonstrate that cellular retinol binding protein [corrected] (CRBP1), a retinoic acid transport protein, GPR50, an orphan G-protein-coupled receptor and nestin, an intermediate filament protein, are down-regulated in short-day photoperiods. The distribution of the three sequences is very similar, with expression located in cells with tanycyte morphology in the region of the ependymal layer where tanycytes are located. Furthermore, CRBP1 expression in the ependymal layer is shown to be independent of a circadian clock and altered testosterone levels associated with testicular regression in short photo-period. Pinealectomy of Siberian hamsters demonstrates CRBP1 expression is likely to be dependent on melatonin output from the pineal gland. This provides evidence that tanycytes are seasonally responsive cells and are likely to be an important part of the mechanism to facilitate seasonal physiology and behaviour in the Siberian hamster.

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.

Novel inhibitor candidates of TRPV2 prevent damage of dystrophic myocytes and ameliorate against dilated cardiomyopathy in a hamster model.

PubMed

Iwata, Yuko; Katayama, Yoshimi; Okuno, Yasushi; Wakabayashi, Shigeo

2018-03-06

Transient receptor potential cation channel, subfamily V, member 2 (TRPV2) is a principal candidate for abnormal Ca 2+ -entry pathways, which is a potential target for therapy of muscular dystrophy and cardiomyopathy. Here, an in silico drug screening and the following cell-based screening to measure the TRPV2 activation were carried out in HEK293 cells expressing TRPV2 using lead compounds (tranilast or SKF96365) and off-patent drug stocks. We identified 4 chemical compounds containing amino-benzoyl groups and 1 compound (lumin) containing an ethylquinolinium group as candidate TRPV2 inhibitors. Three of these compounds inhibited Ca 2+ entry through both mouse and human TRPV2, with IC 50 of less than 10 μM, but had no apparent effect on other members of TRP family such as TRPV1 and TRPC1. Particularly, lumin inhibited agonist-induced TRPV2 channel activity at a low dose. These compounds inhibited abnormally increased Ca 2+ influx and prevented stretch-induced skeletal muscle damage in cultured myocytes from dystrophic hamsters (J2N-k). Further, they ameliorated cardiac dysfunction, and prevented disease progression in vivo in the same J2N-k hamsters developing dilated cardiomyopathy as well as muscular dystrophy. The identified compounds described here are available as experimental tools and represent potential treatments for patients with cardiomyopathy and muscular dystrophy.

Novel inhibitor candidates of TRPV2 prevent damage of dystrophic myocytes and ameliorate against dilated cardiomyopathy in a hamster model

PubMed Central

Iwata, Yuko; Katayama, Yoshimi; Okuno, Yasushi; Wakabayashi, Shigeo

2018-01-01

Transient receptor potential cation channel, subfamily V, member 2 (TRPV2) is a principal candidate for abnormal Ca2+-entry pathways, which is a potential target for therapy of muscular dystrophy and cardiomyopathy. Here, an in silico drug screening and the following cell-based screening to measure the TRPV2 activation were carried out in HEK293 cells expressing TRPV2 using lead compounds (tranilast or SKF96365) and off-patent drug stocks. We identified 4 chemical compounds containing amino-benzoyl groups and 1 compound (lumin) containing an ethylquinolinium group as candidate TRPV2 inhibitors. Three of these compounds inhibited Ca2+ entry through both mouse and human TRPV2, with IC50 of less than 10 μM, but had no apparent effect on other members of TRP family such as TRPV1 and TRPC1. Particularly, lumin inhibited agonist-induced TRPV2 channel activity at a low dose. These compounds inhibited abnormally increased Ca2+ influx and prevented stretch-induced skeletal muscle damage in cultured myocytes from dystrophic hamsters (J2N-k). Further, they ameliorated cardiac dysfunction, and prevented disease progression in vivo in the same J2N-k hamsters developing dilated cardiomyopathy as well as muscular dystrophy. The identified compounds described here are available as experimental tools and represent potential treatments for patients with cardiomyopathy and muscular dystrophy. PMID:29581825

[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.

Brain-derived neurotrophic factor-, neurotrophin-3-, and tyrosine kinase receptor-like immunoreactivity in lingual taste bud fields of mature hamster.

PubMed

Ganchrow, Donald; Ganchrow, Judith R; Verdin-Alcazar, Mary; Whitehead, Mark C

2003-01-01

The neurotrophins brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), as well as their respective tyrosine kinase (Trk) receptors, TrkB and TrkC, influence peripheral target cell innervation, survival, and proliferation. In the mature taste system the role of neurotrophins and their receptors is not known. The mature hamster is an intriguing model because anterior lingual fungiform, unlike posterior lingual foliate and circumvallate, taste buds survive denervation. In light of this difference, we examined whether the degree of neurotrophin- or neurotrophin receptor-like immunoreactivity (IR) normally differs among lingual gemmal fields. In single- and double-labeled immunofluorescent experiments, 3,209 taste bud sections (profiles) from 13 hamsters were examined for immunopositive gemmal cells or nerve fibers using antibodies to BDNF and NT-3, their respective receptors TrkB and TrkC, and the neural marker ubiquitin c-terminal hydrolase L-1 [protein gene product (PGP) 9.5]. In each gemmal field, more than 75% of taste bud profiles showed immunopositivity to BDNF, NT-3, and TrkB. Across bud fields, BDNF-, TrkB-, and BDNF/TrkB-like IR, as well as PGP 9.5 and PGP 9.5/BDNF-like IR in centrally located, fungiform bud cells was greater (P < 0.0001 to P < 0.002) than in circumvallate or foliate buds. Within bud fields, the number of BDNF-like, labeled bud cells/bud profile was greater than that for NT-3-like IR in fungiform (P < 0.0002) and foliate (P < 0.0001) buds. TrkC was immunonegative in gemmal cells. The average density of TrkB- and TrkC-like fiber IR was more pronounced in fungiform than posterior gemmal-bearing papillae. Thus, fungiform papillae, whose taste buds are least affected by denervation, exhibit specific neurotrophin and receptor enrichment. Copyright 2002 Wiley-Liss, Inc.

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.

Cellular changes in the hamster testicular interstitium with ageing and after exposure to short photoperiod.

PubMed

Beltrán-Frutos, E; Seco-Rovira, V; Ferrer, C; Madrid, J F; Sáez, F J; Canteras, M; Pastor, L M

2016-04-01

The aim of this study was to evaluate the cellular changes that occur in the hamster testicular interstitium in two very different physiological situations involving testicular involution: ageing and exposure to a short photoperiod. The animals were divided into an 'age group' with three subgroups - young, adult and old animals - and a 'regressed group' with animals subjected to a short photoperiod. The testicular interstitium was characterised by light and electron microscopy. Interstitial cells were studied histochemically with regard to their proliferation, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP in situ nick end labelling (TUNEL+) and testosterone synthetic activity. We identified two types of Leydig cell: Type A cells showed a normal morphology, while Type B cells appeared necrotic. With ageing, pericyte proliferation decreased but there was no variation in the index of TUNEL-positive Leydig cells. In the regressed group, pericyte proliferation was greater and TUNEL-positive cells were not observed in the interstitium. The testicular interstitium suffered few ultrastructural changes during ageing and necrotic Leydig cells were observed. In contrast, an ultrastructural involution of Leydig cells with no necrosis was observed in the regressed group. In conclusion, the testicular interstitium of Mesocricetus auratus showed different cellular changes in the two groups (age and regressed), probably due to the irreversible nature of ageing and the reversible character of changes induced by short photoperiod.

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

Naphthol AS-BI (7-bromo-3-hydroxy-2-naphtho-o-anisidine) phosphatase and naphthol AS-BI. beta. -D-glucuronidase in Chinese hamster ovary cells: biochemical and flow cytometric studies

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

Dolbeare, F.A.; Phares, W.

1979-01-01

Conditions for the biochemical and flow cytometric assay of 7-bromo-3-hydroxy-2-naphtho-o-anisidine phosphatase and ..beta..-D-glucuronidase activities in Chinese hamster ovary cells were studied. In the biochemical assays, the pH optimum for the phosphatase activity was pH 4.6 with a Km of 10/sup -5/ M; the pH optimum for ..beta..-D-glucuronidase activity was pH 5.0 with a Km of 2 x 10/sup -5/ M. For intact cells the derived constants were 3 to 10 times higher. The rate of hydrolysis of both substrates was also examined by flow cytometry. Cellular fluorescence increased linearly for only about 15 min. Diffusion of the fluorescent product probablymore » caused nonlinearity of the fluorescence increase and was demonstrated by mixing cells incubated with substrate with those that had not been incubated. After 15 min, cells that had not been exposed previously to product or substrate contained the fluorescent product. Cells fractionated into size classes by centrifugal elutriation also were analyzed by flow cytometry for ..beta..-D-glucuronidase activity. The activity increased linearly with the increase in cell size corresponding to the progression from G/sub 1/ through S and into G/sub 2/-M phases of the cell cycle.« less

N-Linked Glycosylation and Sequence Changes in a Critical Negative Control Region of the ASCT1 and ASCT2 Neutral Amino Acid Transporters Determine Their Retroviral Receptor Functions

PubMed Central

Marin, Mariana; Lavillette, Dimitri; Kelly, Sean M.; Kabat, David

2003-01-01

A widely dispersed interference group of retroviruses that includes the feline endogenous virus (RD114), baboon endogenous virus (BaEV), human endogenous virus type W (HERV-W), and type D primate retroviruses uses the human Na+-dependent neutral amino acid transporter type 2 (hASCT2; gene name, SLC1A5) as a common cell surface receptor. Although hamster cells are fully resistant to these viruses and murine cells are susceptible only to BaEV and HERV-W pseudotype viruses, these rodent cells both become highly susceptible to all of the viruses after treatment with tunicamycin, an inhibitor of protein N-linked glycosylation. A partial explanation for these results was recently provided by findings that the orthologous murine transporter mASCT2 is inactive as a viral receptor, that a related (ca. 55% identity) murine paralog (mASCT1; gene name, SLC1A4) mediates infections specifically of BaEV and HERV-W, and that N-deglycosylation of mASCT1 activates it as a receptor for all viruses of this interference group. Because the only two N-linked oligosaccharides in mASCT1 occur in the carboxyl-terminal region of extracellular loop 2 (ECL2), it was inferred that this region contributes in an inhibitory manner to infections by RD114 and type D primate viruses. To directly and more thoroughly investigate the receptor active sites, we constructed and analyzed a series of hASCT2/mASCT2 chimeras and site-directed mutants. Our results suggest that a hypervariable sequence of 21 amino acids in the carboxyl-terminal portion of ECL2 plays a critical role in determining the receptor properties of ASCT2 proteins for all viruses in this interference group. In addition, we analyzed the tunicamycin-dependent viral susceptibility of hamster cells. In contrast to mASCT1, which contains two N-linked oligosaccharides that partially restrict viral infections, hamster ASCT1 contains an additional N-linked oligosaccharide clustered close to the others in the carboxyl-terminal region of ECL2. Removal of this N-linked oligosaccharide by mutagenesis enabled hamster ASCT1 to function as a receptor for all viruses of this interference group. These results strongly suggest that combinations of amino acid sequence changes and N-linked oligosaccharides in a critical carboxyl-terminal region of ECL2 control retroviral utilization of both the ASCT1 and ASCT2 receptors. PMID:12584318

HALOACETONITRILES VS. REGULATED HALOACETIC ACIDS: ARE NITROGEN CONTAINING DBPS MORE TOXIC?

EPA Science Inventory

Haloacetonitriles (HANs) are toxic nitrogenous drinking water disinfection by-products (N-DBPs) and are observed with chlorine, chloramine, or chlorine dioxide disinfection. Using microplate-based Chinese hamster ovary (CHO) cell assays for chronic cytotoxicity and acute genotoxi...

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.

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

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.

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.

Cloning of a Recombinant Plasmid Encoding Thiol-Specific Antioxidant Antigen (TSA) Gene of Leishmania majorand Expression in the Chinese Hamster Ovary Cell Line.

PubMed

Fatemeh, Ghaffarifar; Fatemeh, Tabatabaie; Zohreh, Sharifi; Abdolhosein, Dalimiasl; Mohammad Zahir, Hassan; Mehdi, Mahdavi

2012-01-01

TSA (thiol-specific antioxidant antigen) is the immune-dominant antigen of Leishmania major and is considered to be the most promising candidate molecule for a recombinant or DNA vaccine against leishmaniasis. The aim of the present work was to express a plasmid containing the TSA gene in eukaryotic cells. Genomic DNA was extracted, and the TSA gene was amplified by polymerase chain reaction (PCR). The PCR product was cloned into the pTZ57R/T vector, followed by subcloning into the eukaryotic expression vector pcDNA3 (EcoRI and HindIII sites). The recombinant plasmid was characterised by restriction digest and PCR. Eukaryotic Chinese hamster ovary cells were transfected with the plasmid containing the TSA gene. Expression of the L. major TSA gene was confirmed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting. The plasmid containing the TSA gene was successfully expressed, as demonstrated by a band of 22.1 kDa on Western blots. The plasmid containing the TSA gene can be expressed in a eukaryotic cell line. Thus, the recombinant plasmid may potentially be used as a DNA vaccine in animal models.

CYTOTOXIC EFFECTS OF SOME MINERAL DUSTS ON SYRIAN HAMSTER PERITONEAL MACROPHAGES

PubMed Central

Bey, Elke; Harington, J. S.

1971-01-01

Hamster peritoneal macrophages were grown in cell culture and their response to various conditions was examined. The cultures responded favorably to high concentrations of serum and to medium which had been preconditioned by contact with tumor cells. After 2–3 days of adaptation, they entered into a period of stability which lasted from the 4th to the 9th day. Macrophage cultures in this stable phase were treated with various samples of mineral dusts and their response determined by counting the number of viable macrophages/cm2 at intervals over a period of 72 hr. Crystalline silica Snowit was found to be nontoxic. Amorphous silica Fransil caused a characteristic cytotoxic effect and a rapid decline in cell population at doses less than 150 µg/5 x 105 cells. Of the three different kinds of asbestos used, chrysotile was toxic and amosite and crocidolite nontoxic at equivalent concentrations. A comparison of two preparations of chrysotile which differed in surface area showed that weight rather than surface area determines toxicity. Pretreatment of chrysotile with tryptose phosphate broth under drastic conditions accelerated but did not increase the final intensity of the cytotoxic effect. PMID:4101804

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.

Involvement of PSMD10, CDK4, and Tumor Suppressors in Development of Intrahepatic Cholangiocarcinoma of Syrian Golden Hamsters Induced by Clonorchis sinensis and N-Nitrosodimethylamine

PubMed Central

Uddin, Md. Hafiz; Choi, Min-Ho; Kim, Woo Ho; Jang, Ja-June; Hong, Sung-Tae

2015-01-01

Background Clonorchis sinensis is a group-I bio-carcinogen for cholangiocarcinoma (CCA). Although the epidemiological evidence links clonorchiasis and CCA, the underlying molecular mechanism involved in this process is poorly understood. In the present study, we investigated expression of oncogenes and tumor suppressors, including PSMD10, CDK4, p53 and RB in C. sinensis induced hamster CCA model. Methods Different histochemical/immunohistochemical techniques were performed to detect CCA in 4 groups of hamsters: uninfected control (Ctrl.), infected with C. sinensis (Cs), ingested N-nitrosodimethylamine (NDMA), and both Cs infected and NDMA introduced (Cs+NDMA). The liver tissues from all groups were analyzed for gene/protein expressions by quantitative PCR (qPCR) and western blotting. Principal Findings CCA was observed in all hamsters of Cs+NDMA group with well, moderate, and poorly differentiated types measured in 21.8% ± 1.5%, 13.3% ± 1.3%, and 10.8% ± 1.3% of total tissue section areas respectively. All CCA differentiations progressed in a time dependent manner, starting from the 8th week of infection. CCA stroma was characterized with increased collagen type I, mucin, and proliferative cell nuclear antigen (PCNA). The qPCR analysis showed PSMD10, CDK4 and p16INK4 were over-expressed, whereas p53 was under-expressed in the Cs+NDMA group. We observed no change in RB1 at mRNA level but found significant down-regulation of RB protein. The apoptosis related genes, BAX and caspase 9 were found downregulated in the CCA tissue. Gene/protein expressions were matched well with the pathological changes of different groups except the NDMA group. Though the hamsters in the NDMA group showed no marked pathological lesions, we observed over-expression of Akt/PKB and p53 genes proposing molecular interplay in this group which might be related to the CCA initiation in this animal model. Conclusions/Significance The present findings suggest that oncogenes, PSMD10 and CDK4, and tumor suppressors, p53 and RB, are involved in the carcinogenesis process of C. sinensis induced CCA in hamsters. PMID:26313366

Recombinant lipoprotein-based vaccine candidates against C. difficile infections.

PubMed

Huang, Jui-Hsin; Wu, Chia-Wei; Lien, Shu-Pei; Leng, Chih-Hsiang; Hsiao, Kuang-Nan; Liu, Shih-Jen; Chen, Hsin-Wei; Siu, Leung-Kei; Chong, Pele

2015-08-07

Opportunistically nosocomial infections in hospitalized patients are often related to Clostridium difficile infections (CDI) due to disruption of the intestinal micro-flora by antibiotic therapies during hospitalization. Clostridial exotoxins A and B (TcdA and TcdB) specifically bind to unknown glycoprotein(s) in the host intestine, disrupt the intestinal barrier leading to acute inflammation and diarrhea. The C-terminal receptor binding domain of TcdA (A-rRBD) has been shown to elicit antibody responses that neutralize TcdA toxicity in Vero cell cytotoxicity assays, but not effectively protect hamsters against a lethal dose challenge of C. difficile spores. To develop an effective recombinant subunit vaccine against CDI, A-rRBD was lipidated (rlipoA-RBD) as a rational design to contain an intrinsic adjuvant, a toll-like receptor 2 agonist and expressed in Escherichia coli. The purified rlipoA-RBD was characterized immunologically and found to have the following properties: (a) mice, hamsters and rabbits vaccinated with 3 μg of rlipoA-RBD produced strong antibody responses that neutralized TcdA toxicity in Vero cell cytotoxicity assays; furthermore, the neutralization titer was comparable to those obtained from antisera immunized either with 10 μg of TcdA toxoid or 30 μg of A-rRBD; (b) rlipoA-RBD elicited immune responses and protected mice from TcdA challenge, but offered insignificant protection (10 to 20 %) against C. difficile spores challenge in hamster models; (c) only rlipoA-RBD formulated with B-rRBD consistently confers protection (90 to 100 %) in the hamster challenge model; and (d) rlipoA-RBD was found to be 10-fold more potent than A-rRBD as an adjuvant to enhancing immune responses against a poor antigen such as ovalbumin. These results indicate that rlipoA-RBD formulated with B-rRBD could be an excellent vaccine candidate for preclinical studies and future clinical trials.

Detection of early changes in lung cell cytology by flow-systems analysis techniques. Progress report, July 1--December 31, 1977

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

Steinkamp, J.A.; Hansen, K.M.; Wilson, J.S.

1978-04-01

This report summarizes ongoing experiments to develop cytological and biochemical indicators for measuring damage to respiratory tract cells exposed by inhalation of environmental toxic agents. The specific goal of this project is to apply flow cytometric methods to analyze and detect changes in lung epithelium as a function of exposure to toxic agents such as those associated with the production of synthetic fuels from oil shale and coal. The objectives during the past 6 months were to complete modifications to the multiparameter cell separator by adding a krypton laser with an output capability of specific wavelengths ranging from the uvmore » to the ir; analyze and separate lung cells based on their DNA content; evaluate some new fluorescent DNA and protein stains; and treat hamster lung cells with proteolytic enzymes for increasing cell yield. Future experiments will involve the continued analysis and characterization of exfoliated lung cells based primarily on cellular DNA content, protein, morphological features, and specific enzyme activities; quantitation of macrophage activity; exposure of hamsters to toxic agents such as oil shale particulates and ozone; and continued analysis of cells based on DNA content. As this new technology becomes adapted to analyzing respiratory tract cells, the measurement of physical and biochemical cell properties as a function of exposure to toxic agents will be increased. This analytical approach is designed to assist in the establishment of guidelines for estimating risks to exposed humans.« less

Etoposide; colchicine; mitomycin C and cyclophosphamide tested in the in vitro mammalian cell micronucleus test (MNvit) in Chinese hamster lung (CHL) cells at Covance laboratories; Harrogate UK in support of OECD draft Test Guideline 487.

PubMed

Fowler, Paul; Whitwell, James; Jeffrey, Laura; Young, Jamie; Smith, Katie; Kirkland, David

2010-10-29

The following genotoxic chemicals were tested in the in vitro micronucleus assay, at Covance Laboratories, Harrogate, UK in the Chinese hamster lung cell line CHL. Etoposide (a topoisomerase inhibitor), colchicine (an aneugen), mitomycin C (a DNA cross linking agent) and cyclophosphamide (an alkylating agent requiring metabolic activation) were treated with and without cytokinesis block (by addition of cytochalasin B). This work formed part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 for the in vitro micronucleus test. The toxicity measures used, detecting both cytostasis and cell death, were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index or cytokinesis blocked proliferation index in the presence of cytokinesis block. All of the chemicals tested gave significant increases in the percentage of micronucleated cells with and without cytokinesis block at concentrations giving approximately 60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcomes from this series of tests support the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

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...

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.

After infection with Leishmania infantum, Golden Hamsters (Mesocricetus auratus) become more attractive to female sand flies (Lutzomyia longipalpis).

PubMed

Nevatte, T M; Ward, R D; Sedda, L; Hamilton, J G C

2017-07-21

In Brazil, human and canine visceral leishmaniasis is caused by infection with Leishmania infantum, a Protist parasite transmitted by blood-feeding female Lutzomyia longipalpis sand flies. The objective of this study was to determine if the odour of hamsters, infected with Le. infantum, was more attractive than the odour of the same hamsters, before they were infected. The attractiveness of odour collected from individual hamsters (n = 13), before they were infected, was compared in a longitudinal study, with the attractiveness of the odour of the same hamster in a Y-tube olfactometer bioassay, at a late stage of infection. The odour of six of the golden hamsters was significantly more attractive to 50% of the female sand flies at the end of infection compared to before infection and the odour of four of the golden hamsters was significantly more attractive to 75% of the female sand flies at the end of infection. These results strongly indicate that hamsters infected with Le. infantum become significantly more attractive to a greater proportion of female sand flies as the infection progresses.

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.

Radiosensitization of Hypoxic Tumor Cells by Depletion of Intracellular Glutathione

NASA Astrophysics Data System (ADS)

Bump, Edward A.; Yu, Ning Y.; Brown, J. Martin

1982-08-01

Depletion of glutathione in Chinese hamster ovary cells in vitro by diethyl maleate resulted in enhancement of the effect of x-rays on cell survival under hypoxic conditions but not under oxygenated conditions. Hypoxic EMT6 tumor cells were similarly sensitized in vivo. The action of diethyl maleate is synergistic with the effect of the electron-affinic radiosensitizer misonidazole, suggesting that the effectiveness of misonidazole in cancer radiotherapy may be improved by combining it with drugs that deplete intracellular glutathione.

Radiosensitization of hypoxic tumor cells by depletion of intracellular glutathione

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

Bump, E.A.; Yu, N.Y.; Brown, J.M.

1982-08-06

Depletion of glutathione in Chinese hamster ovary cells in vitro by diethyl maleate resulted in enhancement of the effect of x-rays on cell survival under hypoxic conditions but not under oxygenated conditions. Hypoxic EMT6 tumor cells were similarly sensitized in vivo. The action of diethyl maleate is synergistic with the effect of the electron-affinic radiosensitizer misonidazole, suggesting that the effectiveness of misonidazole in cancer radiotherapy may be improved by combining it with drugs that deplete intracellular glutathione.

Scavenging of long-lived radicals by (-)-epigallocatechin-3- O-gallate and simultaneous suppression of mutation in irradiated mammalian cells

NASA Astrophysics Data System (ADS)

Kumagai, Jun; Nakama, Mitsuo; Miyazaki, Tetsuo; Ise, Tamaki; Kodama, Seiji; Watanabe, Masami

2002-07-01

Effect of (-)-epigallocatechin-3- O-gallate (EGCg) on scavenging long-lived radicals and its biological significance were investigated using electron-spin-resonance spectroscopy and mutation assay in cultured human embryo cells. EGCg scavenged long-lived radicals in irradiated golden hamster embryo cells and albumin solution, and simultaneously reduced mutation frequency in the irradiated human embryo cells. These results indicate that long-lived radials are involved in the induction of mutation by radiation.

A 50-year research journey. From laboratory to clinic.

PubMed

Ross, John

2009-01-01

Prior important research is not always cited, exemplified by Oswald Avery's pioneering discovery that DNA is the genetic transforming factor; it was not cited by Watson and Crick 10 years later. My first laboratory research (National Institutes of Health 1950s) resulted in the clinical development of transseptal left heart catheterization. Laboratory studies on cardiac muscle mechanics in normal and failing hearts led to the concept of afterload mismatch with limited preload reserve. At the University of California, San Diego in La Jolla (1968) laboratory experiments on coronary artery reperfusion after sustained coronary occlusion showed salvage of myocardial tissue, a potential treatment for acute myocardial infarction proven in clinical trials of thrombolysis 14 years later. Among 60 trainees who worked with me in La Jolla, one-third were Japanese and some of their important laboratory experiments are briefly recounted, beginning with Sasayama, Tomoike and Shirato in the 1970 s. Recently, we developed a method for cardiac gene transfer, and subsequently we showed that gene therapy for the defect in cardiomyopathic hamsters halted the progression of advanced disease. Cardiovascular research and medicine are producing continuing advances in technologies for gene transfer and embryonic stem cell transplantation, targeting of small molecules, and tissue and organ engineering.

Antigenic relatedness of glucosyltransferase enzymes from streptococcus mutans.

PubMed

Smith, D J; Taubman, M A

1977-01-01

The antigenic relationship of glucosyltransferases (GTF) produced by different serotypes of Streptococcus mutans was studied by using a functional inhibition assay. Rat, rabbit, or hamster immune fluids, directed to cell-associated or supernatant-derived GTF, were tested against ammonium sulfate-precipitated culture supernatants containing GTF from seven strains of S. mutans representing six different serotypes. An antigenic relationship was shown to exist among GTF from serotypes a, d, and g, since both rat and rabbit antisera directed to serotype a or g GTF inhibited GTF of serotypes d and g similarly and both antisera also inhibited serotype a GTF. Furthermore, serum inhibition patterns indicated that GTF of serotypes c and e, and possibly b, are antigenically related to each other, but are antigenically distinct from GTF of serotype a, d, or g. Serum antibody directed to antigens other than enzyme (e.g., serotype-specific antigen or teichoic acid) had little effect on the inhibition assay. Salivas from rats immunized with cell-associated or supernatant-derived GTF exhibited low but consistent inhibition of GTF activity, which generally corresponded to the serum patterns. The sera of two groups of hamsters immunized with GTF (serotype g), enriched either in water-insoluble or water-soluble glucan synthetic activity, gave patterns of inhibition quite similar to those seen with sera from more heterogenous cell-associated or crude supernatant-derived GTF preparations. Both groups of hamster sera also gave virtually identical patterns, suggesting that the two enzyme forms used as antigen share common antigenic determinants. The results from the three animal models suggest that among the cariogenic organisms tested, two (serotypes a, d, g and b, c, e), or perhaps three (serotypes a, d, g; b; and c, e), different subsets of GTF exist that have distinct antigenic determinants within a subset.

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.

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.

Effect of Escherichia coli-produced recombinant human bone morphogenetic protein 2 on the regeneration of canine segmental ulnar defects.

PubMed

Harada, Yasuji; Itoi, Takamasa; Wakitani, Shigeyuki; Irie, Hiroyuki; Sakamoto, Michiko; Zhao, Dongwei; Nezu, Yoshinori; Yogo, Takuya; Hara, Yasushi; Tagawa, Masahiro

2012-07-01

Because bone morphogenetic protein 2 gene transfected Escherichia coli (E-BMP-2) produce recombinant human BMP-2 (rhBMP-2) more efficiently than mammalian cells (Chinese hamster ovary [CHO]-BMP-2), they may be a more cost-effective source of rhBMP-2 for clinical use. However, use of E-BMP-2 for regenerating long bones in large animals has not been reported. In the current study, we evaluated the healing efficacy of E-BMP-2 in a canine model. We created 2.5-cm critical-size segmental ulnar defects in test animals, then implanted E-BMP-2 and 700 mg of artificial bone (beta-tricalcium phosphate; β-TCP) into the wounds. We examined the differential effects of 5 E-BMP-2 treatments (0, 35, 140, 560, and 2240 μg) across 5 experimental groups (control, BMP35, BMP140, BMP560, and BMP2240). Radiography and computed tomography were used to observe the regeneration process. The groups in which higher doses of E-BMP-2 were administered (BMP560 and BMP2240) displayed more pronounced bone regeneration; the regenerated tissues connected to the host bone, and the cross-sectional areas of the regenerated bone were larger than those of the originals. The groups in which lower doses of E-BMP-2 were administered (BMP35 and BMP140) experienced relatively less bone regeneration; furthermore, the regenerated tissues failed to connect to the host bone. In these groups, the cross-sectional areas of the regenerated bone were equal to or smaller than those of the originals. No regeneration was observed in the control group. These findings suggest that, like CHO-BMP-2, E-BMP-2 can be used for the regeneration of large defects in long bones and that its clinical use might decrease the cost of bone regeneration treatments.

[Seasonal changes of steroid levels in blood plasma of three Phodopus species (Mammalia, Cricetinae)].

PubMed

Feoktistova, N Iu; Kropotkina, M V; Naĭĭdenko, S V

2010-01-01

Seasonal change of the base plasma level of testosterone and cortisol in males and progesterone, estradiol, and cortisol levels in females were analyzed in three Phodopus species: Ph. campbelli (Campbell's dwarf hamster), Ph. sungorus (Russian dwarf hamster), and Ph. roborovskii (Roborovski's dwarf hamster). Our results showed a significant difference in the seasonal plasma level of testosterone and cortisol in males and cortisol in females of all Phodopus species, though the rhythms of breeding activity were similar. The results are discussed in the context of adaptive differences between hormonal patterns of evolutionarily young species (Campbell's dwarf hamster and Russian dwarf hamster) and the evolutionarily old Roborovski's dwarf hamster, the phylogenic position of which is currently under discussion.

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

Reddy, M.K.; Baskaran, K.; Molteni, A.

The angiotensin-converting enzyme (ACE) inhibitor captopril inhibits mitosis in several cell types that contain ACE and renin activity. In the present study, we evaluated the effect of the ACE inhibitors captopril and CGS 13945 (10{sup {minus}8} to 10{sup {minus}2}M) on proliferation and gene expression in hamster pancreatic duct carcinoma cells in culture. These cells lack renin and ACE activity. Both ACE inhibitors produced a dose-dependent reduction in tumor cell proliferation within 24 hr. Captopril at a concentration of 0.36 mM and CGS 13945 at 150 {mu}M decreased cellular growth rate to approximately half that of the control. Neither drug influencedmore » the viability or the cell cycle distribution of the tumor cells. Slot blot analysis of mRNA for four genes, proliferation associated cell nuclear antigen (PCNA), K-ras, protein kinase C-{Beta} (PKC-{Beta}) and carbonic anhydrase II (CA II) was performed. Both ACE inhibitors increased K-ras expression by a factor of 2, and had no effect on CA II mRNA levels. Captopril also lowered PCNA by 40% and CGS 13945 lowered PKC-{Beta} gene expression to 30% of the control level. The data demonstrate that ACE inhibitors exhibit antimitotic activity and differential gene modulation in hamster pancreatic duct carcinoma cells. The absence of renin and ACE activity in these cells suggests that the antimitotic action of captopril and CGS 13945 is independent of renin-angiotensin regulation. The growth inhibition may occur through downregulation of growth-related gene expression. 27 refs., 5 figs.« less

Circadian rhythm disruption by a novel running wheel: Roles of exercise and arousal in blockade of the luteinizing hormone surge

PubMed Central

Duncan, Marilyn J.; Franklin, Kathleen M.; Peng, Xiaoli; Yun, Christopher; Legan, Sandra J.

2014-01-01

Exposure of proestrous Syrian hamsters to a new room, cage, and novel running wheel blocks the luteinizing hormone (LH) surge until the next day in ~75% of hamsters (Legan et al, 2010) [1]. The studies described here tested the hypotheses that 1) exercise and/or 2) orexinergic neurotransmission mediate novel wheel blockade of the LH surge and circadian phase advances. Female hamsters were exposed to a 14L:10D photoperiod and activity rhythms were monitored with infra-red detectors. In Expt. 1, to test the effect of exercise, hamsters received jugular cannulae and on the next day, proestrus (Day 1), shortly before zeitgeber time 5 (ZT 5, 7 hours before lights-off) the hamsters were transported to the laboratory. After obtaining a blood sample at ZT 5, the hamsters were transferred to a new cage with a novel wheel that was either freely rotating (unlocked), or locked until ZT 9, and exposed to constant darkness (DD). Blood samples were collected hourly for 2 days from ZT 5–11 under red light for determination of plasma LH levels by radioimmunoassay. Running rhythms were monitored continuously for the next 10–14 days. The locked wheels were as effective as unlocked wheels in blocking LH surges (no Day 1 LH surge in 6/9 versus 8/8 hamsters, P>0.05) and phase advances in the activity rhythms did not differ between the groups (P= 0.28), suggesting that intense exercise is not essential for novel wheel blockade and phase advance of the proestrous LH surge. Expt. 2 tested whether orexin neurotransmission is essential for these effects. Hamsters were treated the same as in Expt. 1 except they were injected (i.p.) at ZT 4.5 and 5 with either the orexin 1 receptor antagonist SB334867 (15 mg/kg per injection) or vehicle (25% DMSO in 2-hydroxypropyl-beta-cyclodextrin (HCD). SB-334867 inhibited novel wheel blockade of the LH surge (surges blocked in 2/6 SB334867-injected animals versus 16/18 vehicle-injected animals, P<0.02) and also inhibited wheel running and circadian phase shifts, indicating that activation of orexin 1 receptors is necessary for these effects. Expt. 3 tested the hypothesis that novel wheel exposure activates orexin neurons. Proestrous hamsters were transferred at ZT 5 to a nearby room within the animal facility and were exposed to a new cage with a locked or unlocked novel wheel or left in their home cages. At ZT 8, the hamsters were anesthetized, blood was withdrawn, they were perfused with fixative and brains were removed for immunohistochemical localization of Fos, GnRH, and orexin. Exposure to a wheel, whether locked or unlocked, suppressed circulating LH concentrations at ZT 8, decreased the proportion of Fos-activated GnRH neurons, and increased Fos-immunoreactive orexin cells. Unlocked wheels had greater effects than locked wheels on all three endpoints. Thus in a familiar environment, exercise potentiated the effect of the novel wheel on Fos expression because a locked wheel was not a sufficient stimulus to block the LH surge. In conclusion, these studies indicate that novel wheel exposure activates orexin neurons and that blockade of orexin 1 receptors prevents novel wheel blockade of the LH surge. These findings are consistent with a role for both exercise and arousal in mediating novel wheel blockade of the LH surge. PMID:24727338

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.

Tumor blood vessel "normalization" improves the therapeutic efficacy of boron neutron capture therapy (BNCT) in experimental oral cancer

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

D. W. Nigg

2012-01-01

We previously demonstrated the efficacy of BNCT mediated by boronophenylalanine (BPA) to treat tumors in a hamster cheek pouch model of oral cancer with no normal tissue radiotoxicity and moderate, albeit reversible, mucositis in precancerous tissue around treated tumors. It is known that boron targeting of the largest possible proportion of tumor cells contributes to the success of BNCT and that tumor blood vessel normalization improves drug delivery to the tumor. Within this context, the aim of the present study was to evaluate the effect of blood vessel normalization on the therapeutic efficacy and potential radiotoxicity of BNCT in themore » hamster cheek pouch model of oral cancer.« less

Effect of Vandetanib on Andes virus survival in the hamster model of Hantavirus pulmonary syndrome.

PubMed

Bird, Brian H; Shrivastava-Ranjan, Punya; Dodd, Kimberly A; Erickson, Bobbie R; Spiropoulou, Christina F

2016-08-01

Hantavirus pulmonary syndrome (HPS) is a severe disease caused by hantavirus infection of pulmonary microvascular endothelial cells leading to microvascular leakage, pulmonary edema, pleural effusion and high case fatality. Previously, we demonstrated that Andes virus (ANDV) infection caused up-regulation of vascular endothelial growth factor (VEGF) and concomitant downregulation of the cellular adhesion molecule VE-cadherin leading to increased permeability. Analyses of human HPS-patient sera have further demonstrated increased circulating levels of VEGF. Here we investigate the impact of a small molecule antagonist of the VEGF receptor 2 (VEGFR-2) activation in vitro, and overall impact on survival in the Syrian hamster model of HPS. Copyright © 2016. Published by Elsevier B.V.

In vivo stimulation of granulopoiesis by recombinant human granulocyte colony-stimulating factor

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

Cohen, A.M.; Zsebo, K.M.; Inoue, H.

1987-04-01

Osmotic pumps containing Escherichia coli-derived recombinant human granulocyte colony-stimulating factor (rhG-CSF) were attached to indwelling jugular vein catheters and implanted subcutaneously into Golden Syrian hamsters. Within 3 days, peripheral granulocyte counts had increased > 10-fold with a concomitant 4-fold increase in total leukocytes. Microscopic examination of Wright-Giemsa-stained blood smears from rhG-CSF hamsters showed that only the neutrophil subpopulation of granulocytes had increased. After subcutaneous injection at /sup 35/S-labeled rhG-CSF doses of up to 10 ..mu..g x kg/sup -1/ x day/sup -1/ only granulocyte counts were affected. However, at higher dose levels, a transient thrombocytopenia was noted. Erythrocyte and lymphocyte/monocyte countsmore » remained unaffected by rhG-CSF over the entire dose range studied. Total leukocyte counts increased 3-fold within 12 hr after a single s.c. injection of rhG-CSF. This early effect was associated with an increase in the total number of colony-forming cells and the percent of active cycling cells in the marrow. A sustained elevation of peripheral leukocyte and marrow progenitor counts was observed following seven daily s.c. injections of rhG-CSF. The ability of rhG-CSF to increase the production and release of granulocytes from the marrow may underlie the beneficial effect it produced on the restoration of peripheral leukocyte counts in hamsters made leukopenic by treatment with 5-fluorouracil.« less

USC-087 protects Syrian hamsters against lethal challenge with human species C adenoviruses.

PubMed

Toth, Karoly; Spencer, Jacqueline F; Ying, Baoling; Tollefson, Ann E; Hartline, Caroll B; Richard, Eric T; Fan, Jiajun; Lyu, Jinglei; Kashemirov, Boris A; Harteg, Cheryl; Reyna, Dawn; Lipka, Elke; Prichard, Mark N; McKenna, Charles E; Wold, William S M

2018-05-01

Human adenoviruses (AdV) cause generally mild infections of the respiratory and GI tracts as well as some other tissues. However, AdV can cause serious infection in severely immunosuppressed individuals, especially pediatric patients undergoing allogeneic hematopoietic stem cell transplantation, where mortality rates are up to 80% with disseminated disease. Despite the seriousness of AdV disease, there are no drugs approved specifically to treat AdV infections. We report here that USC-087, an N-alkyl tyrosinamide phosphonate ester prodrug of HPMPA, the adenine analog of cidofovir, is highly effective against multiple AdV types in cell culture. USC-087 is also effective against AdV-C6 in our immunosuppressed permissive Syrian hamster model. In this model, hamsters are immunosuppressed by treatment with high dose cyclophosphamide. Injection of AdV-C6 (or AdV-C5) intravenously leads to a disseminated infection that resembles the disease seen in humans, including death. We have tested the efficacy of orally-administered USC-087 against the median lethal dose of intravenously administered AdV-C6. USC-087 completely prevented or significantly decreased mortality when administered up to 4 days post challenge. USC-087 also prevented or significantly decreased liver damage caused by AdV-C6 infection, and suppressed virus replication even when administered 4 days post challenge. These results imply that USC-087 is a promising candidate for drug development against HAdV infections. Copyright © 2018 Elsevier B.V. All rights reserved.

[6]-gingerol dampens hepatic steatosis and inflammation in experimental nonalcoholic steatohepatitis.

PubMed

Tzeng, Thing-Fong; Liou, Shorong-Shii; Chang, Chia Ju; Liu, I-Min

2015-04-15

The aim of the study was to investigate the effects of [6]-gingerol ((S)-5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-3-decanone) in experimental models of non-alcoholic steatohepatitis. HepG2 cells were exposed to 500 µmol/l oleic acid (OA) for 24 h and preincubated for an additional 24 h with [6]-gingerol (25, 50 or 100 µmol/l). [6]-Gingerol (100 µmol/l) inhibited OA-induced triglyceride and inflammatory marker accumulation in HepG2 cells. After being fed a high-fat diet (HFD) for 2 weeks, male golden hamsters were dosed orally with [6]-gingerol (25, 50 or 100 mg/kg/day) once daily for 8 weeks while maintained on HFD. [6]-Gingerol (100 mg/kg/day) alleviated liver steatosis, inflammation, and reversed plasma markers of metabolic syndrome in HFD-fed hamsters. The expression of inflammatory cytokine genes and nuclear transcription factor-κB (NF-κB) were increased in the HFD group; these effects were attenuated by [6]-gingerol. The hepatic mRNA expression of lipogenic genes such as liver X receptor-α, sterol regulating element binding protein-1c and its target genes including acetyl-CoA carboxylase, fatty acid synthase, stearoyl-CoA desaturase 1, and acyl-CoA:diacylglycerol acyltransferase 2 in HFD-fed hamsters was also blocked by [6]-gingerol. [6]-Gingerol may attenuate HFD-induced steatohepatitis by downregulating NF-κB-mediated inflammatory responses and reducing hepatic lipogenic gene expression. Copyright © 2015 Elsevier GmbH. All rights reserved.

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.

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

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

Chromosome instability of HPRT-mutant subclones induced by ionising radiation of various LET.

PubMed

Govorun, R D; Koshlan, I V; Koshlan, N A; Krasavin, E A; Shmakova, N L

2002-01-01

The induction of HPRT-mutations and survival of Chinese hamster cells (line B11ii-FAF28, clone 431) were studied after irradiation by 4He and 12C-ions of various LET (20-360 keV/micrometers), produced by the U-200 heavy ion accelerator. The RBE increases with LET up to the maximum at 100-200 keV/micrometers and then decreases. Cytogenetic analysis was performed on the HPRT-mutant subclones selected from unirradiated Chinese hamster V-79 cells and from HPRT-mutant subclones that arose after exposure to gamma-rays, 1 GeV protons and 14N-ions (LET-77 keV/micrometers), produced by the synchrophasotron and the U-400M heavy ion accelerator. Slow growing mutant subclones were observed. The cytogenetic properties of individual clones were highly heterogeneous and chromosome instability was observed in both spontaneous and radiation-induced mutants. Chromosome instability was highest among spontaneous mutants and decreased with increasing LET. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Demonstration of the oncogenic potential of Herpes simplex viruses and human cytomegalovirus. [UV radiation

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

Rapp, F.; Li, J.L.H.

1975-01-01

The following topics are reviewed: transformation of hamster embryo cells by herpes simplex viruses and human cytomegalovirus; the use of uv radiation and photodynamic action to inactivate virus infectivity while retaining the transformation potential of the virus; detection of virus-specific antigens in transformed cells; oncogenicity of HSV- and CMV-transformed cells in vivo; immunological studies of metastases induced by herpes virus-transformed cells; resistance of transformed cells to superinfection; maintenance of the virus genome in the transformed state; and stimulation of cellular DNA synthesis by human cytomegalovirus. (HLW)

Intracellular proteins produced by mammalian cells in response to environmental stress

NASA Technical Reports Server (NTRS)

Goochee, Charles F.; Passini, Cheryl A.

1988-01-01

The nature of the response of mammalian cells to environmental stress is examined by reviewing results of studies where cultured mouse L cells and baby hamster kidney cells were exposed to heat shock and the synthesis of heat-shock proteins and stress-response proteins (including HSP70, HSC70, HSP90, ubiquitin, and GRP70) in stressed and unstressed cells was evaluated using 2D-PAGE. The intracellular roles of the individual stress response proteins are discussed together with the regulation of the stress response system.

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

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.

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.

High-throughput synchronization of mammalian cell cultures by spiral microfluidics.

PubMed

Lee, Wong Cheng; Bhagat, Ali Asgar S; Lim, Chwee Teck

2014-01-01

The development of mammalian cell cycle synchronization techniques has greatly advanced our understanding of many cellular regulatory events and mechanisms specific to different phases of the cell cycle. In this chapter, we describe a high-throughput microfluidic-based approach for cell cycle synchronization. By exploiting the relationship between cell size and its phase in the cell cycle, large numbers of synchronized cells can be obtained by size fractionation in a spiral microfluidic channel. Protocols for the synchronization of primary cells such as mesenchymal stem cells, and immortal cell lines such as Chinese hamster ovarian cells (CHO-CD36) and HeLa cells are provided as examples.

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

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.

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

Adenoviral production of interleukin-2 at the tumor site removes the need for systemic postconditioning in adoptive cell therapy.

PubMed

Santos, Joao Manuel; Havunen, Riikka; Siurala, Mikko; Cervera-Carrascon, Víctor; Tähtinen, Siri; Sorsa, Suvi; Anttila, Marjukka; Karell, Pauliina; Kanerva, Anna; Hemminki, Akseli

2017-10-01

Systemic high dose interleukin-2 (IL-2) postconditioning has long been utilized in boosting the efficacy of T cells in adoptive cell therapy (ACT) of solid tumors. The resulting severe off-target toxicity of these regimens renders local production at the tumor an attractive concept with possible safety gains. We evaluated the efficacy and safety of intratumorally administered IL-2-coding adenoviruses in combination with tumor-infiltrating lymphocyte therapy in syngeneic Syrian hamsters bearing HapT1 pancreatic tumors and with T cell receptor transgenic ACT in B16.OVA melanoma bearing C57BL/6 mice. The models are complementary: hamsters are semi-permissive for human oncolytic adenovirus, whereas detailed immunological analyses are possible in mice. In both models, local production of IL-2 successfully replaced the need for systemic recombinant IL-2 (rIL-2) administration and increased the efficacy of the cell therapy. Furthermore, vectored delivery of IL-2 significantly enhanced the infiltration of CD8+ T cells, M1-like macrophages, and B-cells while systemic rIL-2 increased CD25 + FoxP3+ T cells at the tumor. In contrast with vectored delivery, histopathological analysis of systemic rIL-2-treated animals revealed significant changes in lungs, livers, hearts, spleens, and kidneys. In summary, local IL-2 production results in efficacy and safety gains in the context of ACT. These preclinical assessments provide the rationale for ongoing clinical translation. © 2017 UICC.

Synthesis of Melanin-Like Pigments by Sporothrix schenckii In Vitro and during Mammalian Infection

PubMed Central

Morris-Jones, Rachael; Youngchim, Sirida; Gomez, Beatriz L.; Aisen, Phil; Hay, Roderick J.; Nosanchuk, Joshua D.; Casadevall, Arturo; Hamilton, Andrew J.

2003-01-01

Melanin has been implicated in the pathogenesis of several important human fungal pathogens. Existing data suggest that the conidia of the dimorphic fungal pathogen Sporothrix schenckii produce melanin or melanin-like compounds; in this study we aimed to confirm this suggestion and to demonstrate in vitro and in vivo production of melanin by yeast cells. S. schenckii grown on Mycosel agar produced visibly pigmented conidia, although yeast cells grown in brain heart infusion and minimal medium broth appeared to be nonpigmented macroscopically. However, treatment of both conidia and yeast cells with proteolytic enzymes, denaturant, and concentrated hot acid yielded dark particles similar in shape and size to the corresponding propagules, which were stable free radicals consistent with identification as melanins. Melanin particles extracted from S. schenckii yeast cells were used to produce a panel of murine monoclonal antibodies (MAbs) which labeled pigmented conidia, yeast cells, and the isolated particles. Tissue from hamster testicles infected with S. schenckii contained fungal cells that were labeled by melanin-binding MAbs, and digestion of infected hamster tissue yielded dark particles that were also reactive. Additionally, sera from humans with sporotrichosis contained antibodies that bound melanin particles. These findings indicate that S. schenckii conidia and yeast cells can produce melanin or melanin-like compounds in vitro and that yeast cells can synthesize pigment in vivo. Since melanin is an important virulence factor in other pathogenic fungi, this pigment may have a similar role in the pathogenesis of sporotrichosis. PMID:12819091

Thyroid cell lines in research on goitrogenesis.

PubMed

Gerber, H; Peter, H J; Asmis, L; Studer, H

1991-12-01

Thyroid cell lines have contributed a lot to the understanding of goitrogenesis. The cell lines mostly used in thyroid research are briefly discussed, namely the rat thyroid cell lines FRTL and FRTL-5, the porcine thyroid cell lines PORTHOS and ARTHOS, The sheep thyroid cell lines OVNIS 5H and 6H, the cat thyroid cell lines PETCAT 1 to 4 and ROMCAT, and the human thyroid cell lines FTC-133 and HTh 74. Chinese hamster ovary (CHO) cells and COS-7 cells, stably transfected with TSH receptor cDNA and expressing a functional TSH receptor, are discussed as examples for non-thyroidal cells, transfected with thyroid genes.

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.

Degradation of recombinant proteins by CHO host cell proteases is prevented by Matriptase-1 knock-out.

PubMed

Laux, Holger; Romand, Sandrine; Nuciforo, Sandro; Farady, Christopher J; Tapparel, Joel; Buechmann-Moeller, Stine; Sommer, Benjamin; Oakeley, Edward J; Bodendorf, Ursula

2018-05-19

An increasing number of non-antibody format proteins are entering the clinical development. However, one of the major hurdles for the production of non-antibody glycoproteins is host cell-related proteolytic degradation, which can drastically impact developability and timelines of pipeline projects. Chinese hamster ovary (CHO) cells are the preferred production host for recombinant therapeutic proteins. Using protease inhibitors, transcriptomics and genetic knockdowns we have identified, out of the more than 700 known proteases in rodents, Matriptase-1 as the major protease involved in degradation of recombinant proteins expressed in CHO-K1 cells. Subsequently Matriptase-1 was deleted in CHO-K1 cells using "Transcription Activator-Like Effector Nucleases" (TALENs) as well as zinc-finger nucleases (ZFNs). This resulted in a superior CHO-K1 matriptase knockout (KO) cell line with strongly reduced or no proteolytic degradation activity towards a panel of recombinantly-expressed proteins. The matriptase KO cell line was evaluated in spike-in experiments, and showed little or no degradation of proteins incubated in culture supernatant derived from the KO cells. This effect was confirmed when the same proteins were recombinantly expressed in the KO cell line. In summary, the combination of novel cell line engineering tools, next generation sequencing screening methods and the recently published Chinese hamster genome has enabled the development of this novel matriptase KO CHO cell line capable of improving expression yields of intact therapeutic proteins. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

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 between the closely related Ps and Pc hamsters, possibly due to different conditions in their natural habitat. Also, the impact of environmental factors like climatic conditions and food resources may differ between species.

IN VITRO AND IN VIVO TOXICITY: A COMPARISON OF ACRYLAMIDE, CYCLOPHOSPHAMIDE, CHLORDECONE, AND DIETHYLSTILBESTROL

EPA Science Inventory

Four chemicals that had been tested in an in vivo toxicological screen were tested in a Chinese hamster ovary (CHO) cytotoxicity assay. Cell density, viability, ATP concentration, rate of protein synthesis, and cellular protein concentration were decreased by exposure to acrylami...

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

Pterocarpanquinone LQB-118 induces apoptosis in Leishmania (Viannia) braziliensis and controls lesions in infected hamsters.

PubMed

Costa, Luciana; Pinheiro, Roberta O; Dutra, Patrícia M L; Santos, Rosiane F; Cunha-Júnior, Edézio F; Torres-Santos, Eduardo C; da Silva, Alcides J M; Costa, Paulo R R; Da-Silva, Silvia A G

2014-01-01

Previous results demonstrate that the hybrid synthetic pterocarpanquinone LQB-118 presents antileishmanial activity against Leishmania amazonensis in a mouse model. The aim of the present study was to use a hamster model to investigate whether LQB-118 presents antileishmanial activity against Leishmania (Viannia) braziliensis, which is the major Leishmania species related to American tegumentary leishmaniasis. The in vitro antileishmanial activity of LQB-118 on L. braziliensis was tested on the promastigote and intracellular amastigote forms. The cell death induced by LQB-118 in the L. braziliensis promastigotes was analyzed using an annexin V-FITC/PI kit, the oxidative stress was evaluated by 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) and the ATP content by luminescence. In situ labeling of DNA fragments by terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was used to investigate apoptosis in the intracellular amastigotes. L. braziliensis-infected hamsters were treated from the seventh day of infection with LQB-118 administered intralesionally (26 µg/kg/day, three times a week) or orally (4,3 mg/kg/day, five times a week) for eight weeks. LQB-118 was active against the L. braziliensis promastigotes and intracellular amastigotes, producing IC50 (50% inhibitory concentration) values of 3,4±0,1 and 7,5±0,8 µM, respectively. LQB-118 induced promastigote phosphatidylserine externalization accompanied by increased reactive oxygen species production and ATP depletion. Intracellular amastigote DNA fragmentation was also observed, without affecting the viability of macrophages. The treatment of L. braziliensis-infected hamsters with LQB-118, either orally or intralesionally, was effective in the control of lesion size, parasite load and increase intradermal reaction to parasite antigen. Taken together, these results show that the antileishmanial effect of LQB-118 extends to L. braziliensis in the hamster model, involves the induction of parasite apoptosis and shows promising therapeutic option by oral or local routes in leishmaniasis.

Pterocarpanquinone LQB-118 Induces Apoptosis in Leishmania (Viannia) braziliensis and Controls Lesions in Infected Hamsters

PubMed Central

Costa, Luciana; Pinheiro, Roberta O.; Dutra, Patrícia M. L.; Santos, Rosiane F.; Cunha-Júnior, Edézio F.; Torres-Santos, Eduardo C.; da Silva, Alcides J. M.; Costa, Paulo R. R.; Da-Silva, Silvia A. G.

2014-01-01

Previous results demonstrate that the hybrid synthetic pterocarpanquinone LQB-118 presents antileishmanial activity against Leishmania amazonensis in a mouse model. The aim of the present study was to use a hamster model to investigate whether LQB-118 presents antileishmanial activity against Leishmania (Viannia) braziliensis, which is the major Leishmania species related to American tegumentary leishmaniasis. The in vitro antileishmanial activity of LQB-118 on L. braziliensis was tested on the promastigote and intracellular amastigote forms. The cell death induced by LQB-118 in the L. braziliensis promastigotes was analyzed using an annexin V-FITC/PI kit, the oxidative stress was evaluated by 2′,7′-dichlorodihydrofluorescein diacetate (H2DCFDA) and the ATP content by luminescence. In situ labeling of DNA fragments by terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was used to investigate apoptosis in the intracellular amastigotes. L. braziliensis-infected hamsters were treated from the seventh day of infection with LQB-118 administered intralesionally (26 µg/kg/day, three times a week) or orally (4,3 mg/kg/day, five times a week) for eight weeks. LQB-118 was active against the L. braziliensis promastigotes and intracellular amastigotes, producing IC50 (50% inhibitory concentration) values of 3,4±0,1 and 7,5±0,8 µM, respectively. LQB-118 induced promastigote phosphatidylserine externalization accompanied by increased reactive oxygen species production and ATP depletion. Intracellular amastigote DNA fragmentation was also observed, without affecting the viability of macrophages. The treatment of L. braziliensis-infected hamsters with LQB-118, either orally or intralesionally, was effective in the control of lesion size, parasite load and increase intradermal reaction to parasite antigen. Taken together, these results show that the antileishmanial effect of LQB-118 extends to L. braziliensis in the hamster model, involves the induction of parasite apoptosis and shows promising therapeutic option by oral or local routes in leishmaniasis. PMID:25340550

Structured triglycerides containing caprylic (8:0) and oleic (18:1) fatty acids reduce blood cholesterol concentrations and aortic cholesterol accumulation in hamsters.

PubMed

Wilson, Thomas A; Kritchevsky, David; Kotyla, Timothy; Nicolosi, Robert J

2006-03-01

The effects of structured triglycerides containing one long chain fatty acid (oleic acid, C18:1) and one short chain saturated fatty acid (caprylic acid, 8:0) on lipidemia, liver and aortic cholesterol, and fecal neutral sterol excretion were investigated in male Golden Syrian hamsters fed a hypercholesterolemic regimen consisting of 89.9% commercial ration to which was added 10% coconut oil and 0.1% cholesterol (w/w). After 2 weeks on the HCD diet, the hamsters were bled, following an overnight fast (16 h) and placed into one of three dietary treatments of eight animals each based on similar plasma cholesterol levels. The hamsters either continued on the HCD diet or were placed on diets in which the coconut oil was replaced by one of two structured triglycerides, namely, 1(3),2-dicaproyl-3(1)-oleoylglycerol (OCC) or 1,3-dicaproyl-2-oleoylglycerol (COC) at 10% by weight. Plasma total cholesterol (TC) in hamsters fed the OCC and COC compared to the HCD were reduced 40% and 49%, respectively (P<0.05). Similarly, hamsters fed the OCC and COC diets reduced their plasma nonHDL cholesterol levels by 47% and 57%, respectively (P<0.05), compared to hamsters fed the HCD after 2 weeks of dietary treatment. Although hamsters fed the OCC (-26%) and COC (-32%) had significantly lower plasma HDL levels compared to HCD, (P<0.05), the plasma nonHDL/HDL cholesterol ratio was significantly lower (P<0.05) compared to the HCD for the OCC-fed (-27%) and the COC-fed (-38%) hamsters, respectively. Compared to the HCD group, aortic esterified cholesterol was 20% and 53% lower for the OCC and COC groups, respectively, with the latter reaching statistical significance, P<0.05. In conclusion, the hamsters fed the structured triglyceride oils had lower blood cholesterol levels and lower aortic accumulation of cholesterol compared to the control fed hamsters.

Visualization and 3D Reconstruction of Flame Cells of Taenia solium (Cestoda)

PubMed Central

Valverde-Islas, Laura E.; Arrangoiz, Esteban; Vega, Elio; Robert, Lilia; Villanueva, Rafael; Reynoso-Ducoing, Olivia; Willms, Kaethe; Zepeda-Rodríguez, Armando; Fortoul, Teresa I.; Ambrosio, Javier R.

2011-01-01

Background Flame cells are the terminal cells of protonephridial systems, which are part of the excretory systems of invertebrates. Although the knowledge of their biological role is incomplete, there is a consensus that these cells perform excretion/secretion activities. It has been suggested that the flame cells participate in the maintenance of the osmotic environment that the cestodes require to live inside their hosts. In live Platyhelminthes, by light microscopy, the cells appear beating their flames rapidly and, at the ultrastructural, the cells have a large body enclosing a tuft of cilia. Few studies have been performed to define the localization of the cytoskeletal proteins of these cells, and it is unclear how these proteins are involved in cell function. Methodology/Principal Findings Parasites of two different developmental stages of T. solium were used: cysticerci recovered from naturally infected pigs and intestinal adults obtained from immunosuppressed and experimentally infected golden hamsters. Hamsters were fed viable cysticerci to recover adult parasites after one month of infection. In the present studies focusing on flame cells of cysticerci tissues was performed. Using several methods such as video, confocal and electron microscopy, in addition to computational analysis for reconstruction and modeling, we have provided a 3D visual rendition of the cytoskeletal architecture of Taenia solium flame cells. Conclusions/Significance We consider that visual representations of cells open a new way for understanding the role of these cells in the excretory systems of Platyhelminths. After reconstruction, the observation of high resolution 3D images allowed for virtual observation of the interior composition of cells. A combination of microscopic images, computational reconstructions and 3D modeling of cells appears to be useful for inferring the cellular dynamics of the flame cell cytoskeleton. PMID:21412407

Immunosuppression Enhances Oncolytic Adenovirus Replication and Antitumor Efficacy in the Syrian Hamster Model

PubMed Central

Thomas, Maria A; Spencer, Jacqueline F; Toth, Karoly; Sagartz, John E; Phillips, Nancy J; Wold, William SM

2012-01-01

We recently described an immunocompetent Syrian hamster model for oncolytic adenoviruses (Ads) that permits virus replication in tumor cells as well as some normal tissues. This model allows exploration of interactions between the virus, tumor, normal organs, and host immune system that could not be examined in the immunodeficient or nonpermissive animal models previously used in the oncolytic Ad field. Here we asked whether the immune response to oncolytic Ad enhances or limits antitumor efficacy. We first determined that cyclophosphamide (CP) is a potent immunosuppressive agent in the Syrian hamster and that CP alone had no effect on tumor growth. Importantly, we found that the antitumor efficacy of oncolytic Ads was significantly enhanced in immunosuppressed animals. In animals that received virus therapy plus immunosuppression, significant differences were observed in tumor histology, and in many cases little viable tumor remained. Notably, we also determined that immunosuppression allowed intratumoral virus levels to remain elevated for prolonged periods. Although favorable tumor responses can be achieved in immunocompetent animals, the rate of virus clearance from the tumor may lead to varied antitumor efficacy. Immunosuppression, therefore, allows sustained Ad replication and oncolysis, which leads to substantially improved suppression of tumor growth. PMID:18665155

The impact of homologous recombination repair deficiency on depleted uranium clastogenicity in Chinese hamster ovary cells: XRCC3 protects cells from chromosome aberrations, but increases chromosome fragmentation.

PubMed

Holmes, Amie L; Joyce, Kellie; Xie, Hong; Falank, Carolyne; Hinz, John M; Wise, John Pierce

2014-04-01

Depleted uranium (DU) is extensively used in both industry and military applications. The potential for civilian and military personnel exposure to DU is rising, but there are limited data on the potential health hazards of DU exposure. Previous laboratory research indicates DU is a potential carcinogen, but epidemiological studies remain inconclusive. DU is genotoxic, inducing DNA double strand breaks, chromosome damage and mutations, but the mechanisms of genotoxicity or repair pathways involved in protecting cells against DU-induced damage remain unknown. The purpose of this study was to investigate the effects of homologous recombination repair deficiency on DU-induced genotoxicity using RAD51D and XRCC3-deficient Chinese hamster ovary (CHO) cell lines. Cells deficient in XRCC3 (irs1SF) exhibited similar cytotoxicity after DU exposure compared to wild-type (AA8) and XRCC3-complemented (1SFwt8) cells, but DU induced more break-type and fusion-type lesions in XRCC3-deficient cells compared to wild-type and XRCC3-complemented cells. Surprisingly, loss of RAD51D did not affect DU-induced cytotoxicity or genotoxicity. DU induced selective X-chromosome fragmentation irrespective of RAD51D status, but loss of XRCC3 nearly eliminated fragmentation observed after DU exposure in wild-type and XRCC3-complemented cells. Thus, XRCC3, but not RAD51D, protects cells from DU-induced breaks and fusions and also plays a role in DU-induced chromosome fragmentation. Copyright © 2014 Elsevier B.V. All rights reserved.

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).

Early Host Responses to Prion Infection: Development of In Vivo and In Vitro Assays

DTIC Science & Technology

2006-05-01

in plasma glycoproteins that are induced by prion infection in mice. The unusual nature of prion disease prompted a systems approach to identify... pheochromocytoma cells (13, 14), spontaneously im- mortalized hamster brain cells (15), the T-antigen immortalized GT1 hypothalamic neuron line (16), and T-antigen...PK- digested (+) or undigested (-) samples are indicated. (MW markers? Nothing unusual here so probably not necessary.)

Modulation of in vitro transformation and the early and late modes of DNA replication of uv-irradiation Syrian hamster cells by caffeine

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

Doniger, J.; DiPaolo, J.A.

1981-09-01

The effect of caffeine on post-uv DNA replication was studied to determine its relevance to carcinogenesis. The level of uv-induced transformed colonies of Syrian hamster embryo cells (HEC) was increased up to fivefold when caffeine was added to cells between 0 and 6 h post-uv. The greatest increase was observed when the interval between uv irradiation and caffeine addition was 4 h. Two modes of DNA replication occurred after uv irradiation. During the early mode (0 to 3 h post-uv) the size of nascent strands, as measured by alkaline sucrose sedimentation, was smaller than those in nonirradiated cells, whereas duringmore » the late mode they recovered to normal size. Caffeine inhibited the rate of elongation of nascent strands during the early mode. When caffeine was added immediately after uv irradiation, the conversion of the early mode to the late mode was inhibited. Studies on the effects of caffeine have now been extended to the late mode. While caffeine has little effect with the fd elements beginning from the 10th day after irradiation is connected with their proliferation but not with the migration out from lymphoid organs.« less

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

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.

Effects of pelleted or powdered diets containing soy protein or sodium caseinate on lipid concentrations and bile acid excretion in golden Syrian hamsters.

PubMed

Butteiger, Dustie N; Krul, Elaine S

2015-08-01

Custom diets are a convenient vector for oral administration of test articles, but the processing and physical form of a diet can affect its nutritional properties and how it is consumed. Here, the authors evaluated the feeding behavior and physiology of golden Syrian hamsters fed diets of either soy or caseinate protein in pelleted or powdered forms for 28 d to determine whether dietary processing and form mediates the physiological effects of dietary proteins. The authors compared body weight, food consumption, serum cholesterol concentration, serum triglyceride concentration, fecal weight and fecal excretion of bile acids between treatment groups. Hamsters fed powdered diets showed higher food consumption than hamsters fed pelleted diets, regardless of protein source. Hamsters fed soy pelleted diets showed lower serum cholesterol concentration and higher fecal excretion of bile acid than hamsters fed caseinate pelleted diets, and serum cholesterol concentration correlated strongly with fecal excretion of bile acid. This correlation suggests that the physiological effects of soy protein on cholesterol and excretion of bile acid might be related or similarly mediated through diet. The differences observed between hamsters on different diets indicate that dietary form can influence both feeding behavior and the physiological effects of a diet in hamsters.

Role of phospholipase A2 (PLA2) inhibitors in attenuating apoptosis of the corneal epithelial cells and mitigation of Acanthamoeba keratitis

PubMed Central

Tripathi, Trivendra; Abdi, Mahshid; Alizadeh, Hassan

2013-01-01

The aim of this study is to determine if the mannose-induced protein (MIP-133) from Acanthamoeba castellanii trophozoites induces apoptosis of corneal epithelial cells through a cytosolic phospholipase A2α (cPLA2α)-mediated pathway. The efficacy of cPLA2α inhibitors to provide protection against Acanthamoeba keratitis was examined in vivo. Chinese hamster corneal epithelial (HCORN) cells were incubated with or without MIP-133. MIP-133 induces significant increase in cPLA2α and macrophage inflammatory protein-2 (MIP-2/CXCL2) levels from corneal cells. Moreover, cPLA2α inhibitors, MAFP (Methyl-arachidonyl fluorophosphonate) and AACOCF3 (Arachidonyl trifluoromethyl ketone), significantly reduce cPLA2α and CXCL2 from these cells (P< 0.05). Additionally, cPLA2α inhibitors significantly inhibit MIP-133-induced apoptosis in HCORN cells (P< 0.05). Subconjunctival injection of purified MIP-133 in Chinese hamster eyes induced cytopathic effects resulting in corneal ulceration. Animals infected with A. castellanii-laden contact lenses and treated with AACOCF3 and CAY10650, showed significantly less severe keratitis as compared with control animals. Collectively, the results indicate that cPLA2α is involved in MIP-133 induced apoptosis of corneal epithelial cells, polymorphonuclear neutrophil infiltration, and production of CXCL2. Moreover, cPLA2α inhibitors can be used as a therapeutic target in Acanthamoeba keratitis. PMID:23792108

Effects of AS2541019, a novel selective PI3Kδ inhibitor, on antibody production and hamster to rat xenotransplantation.

PubMed

Marui, Takanori; Fukahori, Hidehiko; Kawashima, Tomoko; Ito, Misato; Akamatsu, Masahiko; Kaneko, Yoko; Takahashi, Fumie; Imada, Sunao; Morokata, Tatsuaki

2018-05-05

B cell-mediated antibodies play a critical role in protecting the body from infections; however, excessive antibody production is involved in the pathogenesis of autoimmune diseases and transplanted organ rejection. Regulation of antibody production is therefore crucial for overcoming these complications. Phosphatidylinositol-3-kinase p110δ (PI3Kδ), a member of the family of PI3K lipid kinases, is a key mediator of B cell activation and proliferation, with a small molecule PI3Kδ inhibitor having been approved for the treatment of B cell lymphoma. However, the effect of PI3Kδ inhibitors on B cell-mediated antibody production has not been clearly elucidated. In this study, we investigated the effect of the selective PI3Kδ inhibitor, AS2541019, on B cell immunity and antibody production. Our results show that AS2541019 effectively prevented B cell activation and proliferation in vitro, and that oral administration of AS2541019 resulted in significant inhibition of both T-dependent and T-independent de novo antibody production in peripheral blood. Further, in a hamster to rat concordant xenotransplant model, AS2541019 significantly prolonged graft survival time by inhibiting xenoreactive antibody production. Therefore, our study demonstrates that the selective PI3Kδ inhibitor AS2541019 inhibits antibody production through potent inhibitory effects on B cell activation, and can protect against organ dysfunction. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Direct Exposure of Monolayers of Mammalian Cells to Airborne Pollutants in a Unique Culture System.

DTIC Science & Technology

1981-02-01

of growth medium through the filter from the side opposite the cells so that they are nourished and kept moist. Growth medium perfusing through the...planting dispersed cells (Line V79, Chinese hamster lung fibroblasts) on the membrane filters and exposing to the test gas. The toxic effect was... Medium which perfuses through the filters is drawn off through the tubes at the rear wall of the chamber. The test gas enters at the left end of the

Optimization of a pH-shift control strategy for producing monoclonal antibodies in Chinese hamster ovary cell cultures using a pH-dependent dynamic model.

PubMed

Hogiri, Tomoharu; Tamashima, Hiroshi; Nishizawa, Akitoshi; Okamoto, Masahiro

2018-02-01

To optimize monoclonal antibody (mAb) production in Chinese hamster ovary cell cultures, culture pH should be temporally controlled with high resolution. In this study, we propose a new pH-dependent dynamic model represented by simultaneous differential equations including a minimum of six system component, depending on pH value. All kinetic parameters in the dynamic model were estimated using an evolutionary numerical optimization (real-coded genetic algorithm) method based on experimental time-course data obtained at different pH values ranging from 6.6 to 7.2. We determined an optimal pH-shift schedule theoretically. We validated this optimal pH-shift schedule experimentally and mAb production increased by approximately 40% with this schedule. Throughout this study, it was suggested that the culture pH-shift optimization strategy using a pH-dependent dynamic model is suitable to optimize any pH-shift schedule for CHO cell lines used in mAb production projects. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

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.

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

Genotoxicity tests on D-tagatose.

PubMed

Kruger, C L; Whittaker, M H; Frankos, V H

1999-04-01

D-tagatose is a low-calorie sweetener that tastes like sucrose. Its genotoxic potential was examined in five standard assays: the Ames Salmonella typhimurium reverse mutation assay, the Escherichia coli/mammalian microsome assay, a chromosomal aberration assay in Chinese hamster ovary cells, a mouse lymphoma forward mutation assay, and an in vivo mouse micronucleus assay. D-tagatose was not found to increase the number of revertants per plate relative to vehicle controls in either the S. typhimurium tester strains or the WP2uvrA- tester strain with or without metabolic activation at doses up to 5000 microg/plate. No significant increase in Chinese hamster ovary cells with chromosomal aberrations was observed at concentrations up to 5000 microg/ml with or without metabolic activation. D-tagatose was not found to increase the mutant frequency in mouse lymphoma L5178Y cells with or without metabolic activation up to concentrations of 5000 microg/ml. D-tagatose caused no significant increase in micronuclei in bone marrow polychromatic erythrocytes at doses up to 5000 mg/kg. D-tagatose was not found to be genotoxic under the conditions of any of the assays described above. Copyright 1999 Academic Press.

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.

Endrin-induced histopathological changes and lipid peroxidation in livers and kidneys of rats, mice, guinea pigs and hamsters.

PubMed

Hassan, M Q; Numan, I T; al-Nasiri, N; Stohs, S J

1991-01-01

Endrin toxicity may be due to an oxidative stress associated with increased lipid peroxidation, decreased glutathione content, and inhibition of glutathione peroxidase activity. Extensive interspecies variability exists in sensitivity towards endrin. Therefore, histopathological changes and lipid peroxidation in the livers and kidneys of rats, mice, hamsters, and guinea pigs were examined 24 hr after the administration of 4 mg endrin/kg body weight orally in corn oil. Degeneration and necrotic changes with inflammatory cell infiltration were observed in livers and kidneys, and interspecies variability occurred. Fatty changes in the form of hepatic foam cells with cytoplasmic vacuolation were present. Lipofuscin pigments, associated with lipid peroxidation, were observed in hepatocytes and Kupffer cells. These histopathological conditions were prevented in rats which had been pretreated with butylated hydroxyanisole, vitamins E and C, or cysteine, antioxidants and free radical scavengers which have previously been shown to inhibit lipid peroxidation. The extent of endrin-induced lipid peroxidation correlated well with the degree of histopathological changes. Thus, histological changes consistent with the induction of an oxidative stress were observed following the administration of endrin to various animal species.

Proceedings of the 2013 National Toxicology Program Satellite Symposium

PubMed Central

Elmore, Susan A.; Boyle, Michael C.; Boyle, Molly H.; Cora, Michelle C.; Crabbs, Torrie A.; Cummings, Connie A.; Gruebbel, Margarita M.; Johnson, Crystal L.; Malarkey, David E.; McInnes, Elizabeth F.; Nolte, Thomas; Shackelford, Cynthia C.; Ward, Jerrold M.

2014-01-01

The 2013 annual National Toxicology Program (NTP) Satellite Symposium, entitled “Pathology Potpourri” was held in Portland, Oregon in advance of the Society of Toxicologic Pathology's 32nd annual meeting. The goal of the NTP Symposium is to present current diagnostic pathology or nomenclature issues to the toxicologic pathology community. This article presents summaries of the speakers' presentations, including diagnostic or nomenclature issues that were presented, along with select images that were used for audience voting and discussion. Some lesions and topics covered during the symposium included a caudal tail vertebra duplication in mice; nephroblastematosis in rats; ectopic C cell tumor in a hamster; granular cell aggregates/tumor in the uterus of a hamster; Pneumocystis carinii in the lung of a rat; iatrogenic chronic inflammation in the lungs of control rats; hepatoblastoma arising within an adenoma in a mouse; humoral hypercalcemia of benignancy in a transgenic mouse; acetaminophen induced hepatoxicity in rats; electron microscopy images of iatrogenic intraerythrocytic inclusions in transgenic mice; questionable hepatocellular degeneration/cell death/artifact in rats; atypical endometrial hyperplasia in rats; malignant mixed Müllerian tumors/carcinosarcomas in rats; differential diagnoses of proliferative lesions the intestine of rodents; and finally obstructive nephropathy caused by melamine poisoning in a rat. PMID:24334674

Molecular and cytogenetic characterization of a chinese hamster/human hybrid cell line containing a der (21)t(Ypter [yields] cenY::cen21 [yields] 21qter) chromosome

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

Patterson, D.; Hart, I.; Jones, C.

1993-01-01

Human/rodent somatic cell hybrids have been exceedingly useful in assigning human genes and DNA sequences to specific human chromosomes. As new technologies for analyzing the human chromosome complement of such human/rodent hybrid cells become available, it is of critical importance that these be applied to enhance characterization of existing hybrids. This is particularly important since human chromosomes in such hybrids have been observed to rearrange with time. We report here the use of fluorescence in situ hybridization of DNA probes to metaphase chromosomes to analyze one hybrid designated 72532X6. This analysis shows that the chromosome suspected to be a normalmore » human chromosome 21 in this hybrid is actually a translocation chromosome containing Yp and 21 q. In addition, the hybrid contains a fragment of human chromosome 9 translocated to a Chinese hamster chromosome. Analysis of the chromosomes from the human donor indicates that his chromosomes are normal. Thus, this translocation chromosome appears to have arisen after formation of the hybrid. 14 refs., 2 figs.« less

Studies of the Outer Membrane Proteins of Campylobacter Jejuni for Vaccine Development

DTIC Science & Technology

1991-11-26

Mycobacterium tuberculosis, and M.leprae (66%) and mitochondrial protein p1 precursor of human and Chinese hamster cells (64%), and rubisco subunit binding...175) SAWG--DIgNIISDAP’KXVGRXgVITVK (202) 64% Rubisco subunit binding-protein alpha subunit of wheat (151) SAGN--OELIZGANADAIDOGPOVVLStE (178) 57

GLUTATHIONE (GSH) CONCENTRATIONS VARY WITH THE CELL CYCLE IN MATURING HAMSTER OOCYTES, ZYGOTES AND PRE-IMPLANATION EMBRYOS

EPA Science Inventory

Abstract
Glutathione (GSH) is thought to play critical roles in oocyte function including spindle maintenance and provision of reducing power needed to initiate sperm chromatin decondensation. Previous observations that GSH concentrations are higher in mature than immature o...

Testing of the cytotoxic effects of sulfate pulp mill waste waters.

PubMed

Cernáková, M; Golis, E

1994-01-01

The effect of 22 technological waste water samples and of some standards was tested on bacteria, fungi, chlorococcal algae, flagellata, plant cells, cells of Tubifex tubifex, hamster cells V79 and the fish Lebistes reticulatus. Of these 22 samples, some inhibition of cell life processes was displayed by the black liquor formed in the production of paper pulp and viscose pulp, by the waste solution produced during the preparation of bleaching agents for paper pulp and viscose pulp, and by the residual liquor after hypochlorite treatment of paper pulp.

Replicating Single-Cycle Adenovirus Vectors Generate Amplified Influenza Vaccine Responses.

PubMed

Crosby, Catherine M; Matchett, William E; Anguiano-Zarate, Stephanie S; Parks, Christopher A; Weaver, Eric A; Pease, Larry R; Webby, Richard J; Barry, Michael A

2017-01-15

Head-to-head comparisons of conventional influenza vaccines with adenovirus (Ad) gene-based vaccines demonstrated that these viral vectors can mediate more potent protection against influenza virus infection in animal models. In most cases, Ad vaccines are engineered to be replication-defective (RD-Ad) vectors. In contrast, replication-competent Ad (RC-Ad) vaccines are markedly more potent but risk causing adenovirus diseases in vaccine recipients and health care workers. To harness antigen gene replication but avoid production of infectious virions, we developed "single-cycle" adenovirus (SC-Ad) vectors. Previous work demonstrated that SC-Ads amplify transgene expression 100-fold and produce markedly stronger and more persistent immune responses than RD-Ad vectors in Syrian hamsters and rhesus macaques. To test them as potential vaccines, we engineered RD and SC versions of adenovirus serotype 6 (Ad6) to express the hemagglutinin (HA) gene from influenza A/PR/8/34 virus. We show here that it takes approximately 33 times less SC-Ad6 than RD-Ad6 to produce equal amounts of HA antigen in vitro SC-Ad produced markedly higher HA binding and hemagglutination inhibition (HAI) titers than RD-Ad in Syrian hamsters. SC-Ad-vaccinated cotton rats had markedly lower influenza titers than RD-Ad-vaccinated animals after challenge with influenza A/PR/8/34 virus. These data suggest that SC-Ads may be more potent vaccine platforms than conventional RD-Ad vectors and may have utility as "needle-free" mucosal vaccines. Most adenovirus vaccines that are being tested are replication-defective adenoviruses (RD-Ads). This work describes testing newer single-cycle adenovirus (SC-Ad) vectors that replicate transgenes to amplify protein production and immune responses. We show that SC-Ads generate markedly more influenza virus hemagglutinin protein and require substantially less vector to generate the same immune responses as RD-Ad vectors. SC-Ads therefore hold promise to be more potent vectors and vaccines than current RD-Ad vectors. Copyright © 2017 Crosby et al.

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-induced oxidative stress and neuronal cell death in the hippocampus region of brain, suggesting a novel therapeutic approach of melatonin for management of cognition and memory function in females under hyperthyroid condition. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

Dissecting linear and conformational epitopes on the native thyrotropin receptor.

PubMed

Ando, Takao; Latif, Rauf; Daniel, Samira; Eguchi, Katsumi; Davies, Terry F

2004-11-01

The TSH receptor (TSHR) is the primary antigen in Graves' disease. In this condition, autoantibodies to the TSHR that have intrinsic thyroid-stimulating activity develop. We studied the epitopes on the native TSHR using polyclonal antisera and monoclonal antibodies (mAbs) derived from an Armenian hamster model of Graves' disease. Of 14 hamster mAbs analyzed, five were shown to bind to conformational epitopes including one mAb with potent thyroid-stimulating activity. Overlapping conformational epitopes were determined by cell-binding competition assays using fluorescently labeled mAbs. We identified two distinct conformational epitopes: epitope A for both stimulating and blocking mAbs and epitope B for only blocking mAbs. Examination of an additional three mouse-derived stimulating TSHR-mAbs also showed exclusive binding to epitope A. The remaining nine hamster-derived mAbs were neutral or low-affinity blocking antibodies that recognized linear epitopes within the TSHR cleaved region (residues 316-366) (epitope C). Serum from the immunized hamsters also recognized conformational epitopes A and B but, in addition, also contained high levels of TSHR-Abs interacting within the linear epitope C region. In summary, these studies indicated that the natively conformed TSHR had a restricted set of epitopes recognized by TSHR-mAbs and that the binding site for stimulating TSHR-Abs was highly conserved. However, high-affinity TSHR-blocking antibodies recognized two conformational epitopes, one of which was indistinguishable from the thyroid-stimulating epitope. Hence, TSHR-stimulating and blocking antibodies cannot be distinguished purely on the basis of their conformational epitope recognition.

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

Effects of thalidomide on DMBA-induced oral carcinogenesis in hamster with respect to angiogenesis.

PubMed

Yang, Y; Ge, J-P; Zhou, Z-T

2009-05-01

Thalidomide has been shown to have anti-angiogenic effects in pre-clinical models as well as a significant antitumor effect in hematologic tumors. However, the effects of thalidomide on oral pre-malignant lesions and oral carcinogenesis remain unexplored. The authors aimed to investigate the chemopreventive effect of thalidomide on 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters with respect to angiogenesis. Seventy male Syrian golden hamsters were randomly divided into five groups, with two of 20 and three of 10. DMBA solution (0.5% in acetone) was applied topically to the left cheek pouch of male Syrian golden hamsters in group A and B, while animals in group C were painted with acetone, three times a week for 6 weeks. For the next 18 weeks, animals in group B and D received thalidomide daily (40 mg/kg body weight/day) by gavage, animals in group A and C received same volume of saline. Animals in group E received no treatment and served as blank control. At the end of the experiment, animals were killed and tissue samples were collected for examinations. Thalidomide significantly decreased the squamous cell carcinoma (SCC) incidence from 57.9 to 11.8%; angiogenesis was inhibited in dysplasia and SCC. The gene expression of vascular endothelium growth factor and tumor necrosis factor (TNF)-alpha was downregulated. Thalidomide has inhibitory effect against the malignant transformation of oral pre-cancerous lesion and angiogenesis during oral carcinogenesis. Such inhibition is related to its modulation of TNF-alpha.

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.

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.

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.

The effects of simultaneous hyperlipemia-hyperglycemia on the resistance arteries, myocardium and kidney glomeruli.

PubMed

Costache, G; Popov, D; Georgescu, A; Cenuse, M; Jinga, V V; Simionescu, M

2000-01-01

The experimental model of Golden Syrian hamster subjected to concomitant hyperlipemia (diet-induced) and diabetes (by streptozotocin injection) for 24 weeks is characterised by the prevalence of micro- and macroangiopathies. We have used the hyperlipemic-diabetic (HD) hamsters to investigate: a) whether there is an alteration in the reactivity of the resistance arteries (mean internal diameter: 210-250 microm), b) if present, which are the structural and biochemical changes that accompany the functional modifications, and c) to examine the pathomorphological changes induced by the association of hyperlipemia and diabetes on vital organs such as myocardium and kidney glomeruli. To these aims, biochemical assays of plasma components, light- and electronmicroscopy, myographic, morphometric and spectrofluorimetric techniques were used. The mesenteric resistance arteries of HD hamsters exhibited (as compared to similar arteries in normals) a decreased contractile response to noradrenaline (1.86+/-0.35 vs. 2.43+/-0.21), and an impeded endothelium dependent relaxation to acetylcholine (approximately 61.40% vs. approximately 79.80%). The association of hyperlipemia with diabetes induced changes in morphology of the resistance arteries consisting in approximately 10% increase of the intima plus media cross-sectional area, approximately 20% decrease of the vascular lumen area, and approximately 2.85 fold augmentation of the wall to lumen ratio. The resistance arteries exhibited structural modifications of the endothelium (up to 8 copies of Weibel-Palade bodies/endothelial cell), and smooth muscle cells (secretory phenotype), and in the vessels media small calcification cores appeared embedded in a hyperplasic extracellular matrix. The vascular mesenteric bed of the HD hamsters contained approximately 2.30 and approximately 1.30 fold increased concentrations of AGE-collagen and pentosidine, respectively, above the normal values. The HD hamsters displayed also modifications that may be dependent on or may lead to an increase in blood pressure, such as: a) approximately 2 fold increase in the activity of serum angiotensin converting enzyme; b) approximately 4.8 fold enhancement of erythrocytes fragility (as a measure of the oxidative stress); c) left ventricular hypertrophy associated with a progressive disarray of cardiomyocyte contractile fibers, interruptions of the Z bands, and accumulation of collagen-rich extracellular matrix indicative of interstitial fibrosis; d) the kidney glomerular capillaries appeared partially or totally collapsed, with a thickened basement membrane which appeared polymorphic, and in some locations made up of successive layers connected by fine bridges and intercalated nodules; in addition, an increase (approximately 1.50 fold) of the mesangial volume was indicative of glomerulosclerosis.

A selective cyclooxygenase-2 inhibitor (Etodolac) prevents spontaneous biliary tumorigenesis in a hamster bilioenterostomy model.

PubMed

Kitasato, Amane; Kuroki, Tamotsu; Adachi, Tomohiko; Ono, Shinichiro; Tanaka, Takayuki; Tsuneoka, Noritsugu; Hirabaru, Masataka; Takatsuki, Mitsuhisa; Eguchi, Susumu

2014-01-01

Secondary biliary carcinomas are associated with persistent reflux cholangitis after bilioenterostomy. Cyclooxygenase-2 (COX-2) has been a target for cancer prevention. The aim of this study was to evaluate the chemopreventive efficacy of long-term treatment with a selective COX-2 inhibitor medication during the natural course after bilioenterostomy without chemical induction. Syrian golden hamsters which underwent choledochojejunostomy were randomly divided into two groups: the control group (n = 31), which was fed a normal diet, and the etodolac group (n = 33), which was fed 0.01% etodolac (a selective COX-2 inhibitor) mixed in the meal. The hamsters were killed at the postoperative weeks 20-39, 40-59, 60-79, or 80-100. Biliary neoplasms, cholangitis, proliferating cell nuclear antigen labeling index (PCNA-LI) of the biliary epithelium, and prostaglandin E2 (PGE2) production were evaluated. The occurrence rates of biliary neoplasm were 43.8 and 15.2% in the control and etodolac groups, respectively (p < 0.05). The incidence of biliary neoplasm increased as time progressed in the control group, whereas it remained at a low level throughout the experimental period in the etodolac group. PGE2 products tended to be lower in the etodolac group, and PCNA-LI was significantly lower in the etodolac group (p < 0.01). These results suggest that the medication etodolac suppresses cell proliferation of the biliary epithelium, thereby preventing biliary carcinogenesis. Etodolac is expected to prevent secondary biliary carcinogenesis caused by persistent reflux cholangitis after bilioenterostomy. © 2014 S. Karger AG, Basel.

Mathematical Model Formulation And Validation Of Water And Solute Transport In Whole Hamster Pancreatic Islets

PubMed Central

Benson, Charles T.; Critser, John K.

2014-01-01

Optimization of cryopreservation protocols for cells and tissues requires accurate models of heat and mass transport. Model selection often depends on the configuration of the tissue. Here, a mathematical and conceptual model of water and solute transport for whole hamster pancreatic islets has been developed and experimentally validated incorporating fundamental biophysical data from previous studies on individual hamster islet cells while retaining whole-islet structural information. It describes coupled transport of water and solutes through the islet by three methods: intracellularly, intercellularly, and in combination. In particular we use domain decomposition techniques to couple a transmembrane flux model with an interstitial mass transfer model. The only significant undetermined variable is the cellular surface area which is in contact with the intercellularly transported solutes, Ais. The model was validated and Ais determined using a 3 × 3 factorial experimental design blocked for experimental day. Whole islet physical experiments were compared with model predictions at three temperatures, three perfusing solutions, and three islet size groups. A mean of 4.4 islets were compared at each of the 27 experimental conditions and found to correlate with a coefficient of determination of 0.87 ± 0.06 (mean ± S.D.). Only the treatment variable of perfusing solution was found to be significant (p < 0.05). We have devised a model that retains much of the intrinsic geometric configuration of the system, and thus fewer laboratory experiments are needed to determine model parameters and thus to develop new optimized cryopreservation protocols. Additionally, extensions to ovarian follicles and other concentric tissue structures may be made. PMID:24950195

5-Fluorouracil, colchicine, benzo[a]pyrene and cytosine arabinoside tested in the in vitro mammalian cell micronucleus test (MNvit) in Chinese hamster V79 cells at Covance Laboratories, Harrogate, UK in support of OECD draft Test Guideline 487.

PubMed

Whitwell, James; Fowler, Paul; Allars, Sarah; Jenner, Karen; Lloyd, Melvyn; Wood, Debbie; Smith, Katie; Young, Jamie; Jeffrey, Laura; Kirkland, David

2010-10-29

The reference genotoxic agents 5-fluorouracil (a nucleoside analogue, characterised by a steep dose response profile), colchicine (an aneugen that inhibits tubulin polymerisation), benzo[a]pyrene (a polycyclic aromatic hydrocarbon requiring metabolic activation) and cytosine arabinoside (a nucleoside analogue that inhibits the gap-filling step of excision repair) were tested in the in vitro micronucleus assay using the Chinese hamster V79 cell line at Covance Laboratories, Harrogate, UK. All chemicals were treated in the absence and presence of cytokinesis block (via addition of cytochalasin B) with this work forming part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 on the In Vitro Mammalian Cell Micronucleus Test (MNvit). The toxicity measures used, detecting a possible combination of both cytostasis and cell death (though not cell death directly), were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index in the presence of cytokinesis block. All of the chemicals tested either gave marked increases in the percentage of micronucleated cells with and without cytokinesis block, or did not induce micronuclei at concentrations giving approximately 50-60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcome from this series of tests supports the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

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.

2-Deoxy-D-glucose, not mercaptoacetate, induces a reversible reduction of body temperature in male desert hamsters (Phodopus roborovskii).

PubMed

Chi, Qing-Sheng; Li, Xiu-Juan; Wang, De-Hua

2018-01-01

The initiation of torpor is supposed to be related to the availability of metabolic fuels. Studies on metabolic fuel inhibition of glucose by using 2-deoxy-D-glucose (2DG) or fatty acid by mercaptoacetate (MA) in heterothermic mammals produced mixed outcomes. To examine the roles of availability of glucose and fatty acid in the initiation of torpor in desert hamsters (Phodopus roborovskii), we intraperitoneally administrated 2DG and MA to summer-acclimated male hamsters while body temperature (T b ), metabolic rate (MR) and respiratory quotient (RQ) were simultaneously recorded to monitor their thermoregulatory response. 2DG induced a reversible reduction of T b in desert hamsters both at ambient temperature (T a ) of 23°C and 5°C. At T a of 23°C, T b , MR and RQ decreased in a dose-dependent manner with a large T b -T a differential (> 6.5°C) and a lowest T b of 28.0°C which were comparable to those in fasted hamsters. At T a of 5°C, 2DG-treated hamsters also decreased T b to the same level as at T a 23°C, but MR was significantly higher than that at T a of 23°C at each dose, suggesting doses of 2DG directly affected the hypothalamic T b set-point. Different from fasted hamsters which maintain normothermic at T a of 5°C, 2DG-treated hamsters showed a substantial reduction of T b at T a 5°C, indic a ting an overwhelming effect on the thermoregulatory system regardless of T a . Furthermore, the rapid decrease of T b and outstretched body posture in 2DG-treated hamsters suggest that the effects of 2DG were not simply mimicking the torpor pathways but that other mechanisms are involved. Interestingly, MA failed to induce a torpor-like state in male desert hamsters. Our results suggest that availability of glucose rather than fatty acid plays an important role for initiation of torpor in desert hamsters. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of steroid receptors from the androgen responsive DDT1 cell line and the nonresponsive HVP cell line.

PubMed

Norris, J S; Kohler, P O

1978-01-01

Two hamster cell lines have been isolated from androgen target tissue. The DDT1 cells derived from ductus deferens tissue exhibit a growth response to androgens, while the HVP cells derived from ventral prostate are androgen unresponsive. Both cell lines contain androgen receptors, that are similar when compared by kinetic methods, sedimentation velocity, chromatographic procedures or nuclear translocation ability. The forms of the high salt extracted nuclear receptors are indistinguishable chromatographically. Therefore, we postulate that the lesion preventing androgen induced growth in the HVP cell line is subseqent to nuclear translocation of the steroid receptor complex.

Isolation of Estrogen Regulated Genes from MCF-7 Human Mammary Cancer Cells

DTIC Science & Technology

1990-07-13

Syrian hamster BHK cells. The expression of approximately five hundred clones increased at various points in Gl transit (Hirschhom er d., 1984). No...hyperplasia of ductal epithelium of the mammary gland (Lyons etal., 1958). Biochemical changes in uterine wet weight, protein content, and nucleic... transition from a resting to a growing state (Kaufman and Sharp, 1983). Similarly post- transcriptional processing appears to be important in the ceU

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

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

Pichia pastoris secretes recombinant proteins less efficiently than Chinese hamster ovary cells but allows higher space-time yields for less complex proteins

PubMed Central

Maccani, Andreas; Landes, Nils; Stadlmayr, Gerhard; Maresch, Daniel; Leitner, Christian; Maurer, Michael; Gasser, Brigitte; Ernst, Wolfgang; Kunert, Renate; Mattanovich, Diethard

2014-01-01

Chinese hamster ovary (CHO) cells are currently the workhorse of the biopharmaceutical industry. However, yeasts such as Pichia pastoris are about to enter this field. To compare their capability for recombinant protein secretion, P. pastoris strains and CHO cell lines producing human serum albumin (HSA) and the 3D6 single chain Fv-Fc anti-HIV-1 antibody (3D6scFv-Fc) were cultivated in comparable fed batch processes. In P. pastoris, the mean biomass-specific secretion rate (qp) was 40-fold lower for 3D6scFv-Fc compared to HSA. On the contrary, qp was similar for both proteins in CHO cells. When comparing both organisms, the mean qp of the CHO cell lines was 1011-fold higher for 3D6scFv-Fc and 26-fold higher for HSA. Due to the low qp of the 3D6scFv-Fc producing strain, the space-time yield (STY) was 9.6-fold lower for P. pastoris. In contrast, the STY of the HSA producer was 9.2-fold higher compared to CHO cells because of the shorter process time and higher biomass density. The results indicate that the protein secretion machinery of P. pastoris is much less efficient and the secretion rate strongly depends on the complexity of the recombinant protein. However, process efficiency of the yeast system allows higher STYs for less complex proteins. PMID:24390926

Comparative study of the cytotoxic and genotoxic effects of titanium oxide and aluminium oxide nanoparticles in Chinese hamster ovary (CHO-K1) cells.

PubMed

Di Virgilio, A L; Reigosa, M; Arnal, P M; Fernández Lorenzo de Mele, M

2010-05-15

The aim of this study was to analyze the cytotoxicity and genotoxicity of titanium oxide (TiO(2)) and aluminium oxide (Al(2)O(3)) nanoparticles (NPs) on Chinese hamster ovary (CHO-K1) cells using neutral red (NR), mitochondrial activity (by MTT assay), sister chromatid exchange (SCE), micronucleus (MN) formation, and cell cycle kinetics techniques. Results showed a dose-related cytotoxic effect evidenced after 24h by changes in lysosomal and mitochondrial dehydrogenase activity. Interestingly, transmission electronic microscopy (TEM) showed the formation of perinuclear vesicles in CHO-K1 cells after treatment with both NPs during 24h but no NP was detected in the nuclei. Genotoxic effects were shown by MN frequencies which significantly increased at 0.5 and 1 microg/mL TiO(2) and 0.5-10 microg/mL Al(2)O(3). SCE frequencies were higher for cells treated with 1-5 microg/mL TiO(2). The absence of metaphases evidenced cytotoxicity for higher concentrations of TiO(2). No SCE induction was achieved after treatment with 1-25 microg/mL Al(2)O(3). In conclusion, findings showed cytotoxic and genotoxic effects of TiO(2) and Al(2)O(3) NPs on CHO-K1 cells. Possible causes of controversial reports are discussed further on. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Central Control of Circadian Phase in Arousal-Promoting Neurons

PubMed Central

Mahoney, Carrie E.; McKinley Brewer, Judy; Bittman, Eric L.

2013-01-01

Cells of the dorsomedial/lateral hypothalamus (DMH/LH) that produce hypocretin (HCRT) promote arousal in part by activation of cells of the locus coeruleus (LC) which express tyrosine hydroxylase (TH). The suprachiasmatic nucleus (SCN) drives endogenous daily rhythms, including those of sleep and wakefulness. These circadian oscillations are generated by a transcriptional-translational feedback loop in which the Period (Per) genes constitute critical components. This cell-autonomous molecular clock operates not only within the SCN but also in neurons of other brain regions. However, the phenotype of such neurons and the nature of the phase controlling signal from the pacemaker are largely unknown. We used dual fluorescent in situ hybridization to assess clock function in vasopressin, HCRT and TH cells of the SCN, DMH/LH and LC, respectively, of male Syrian hamsters. In the first experiment, we found that Per1 expression in HCRT and TH oscillated in animals held in constant darkness with a peak phase that lagged that in AVP cells of the SCN by several hours. In the second experiment, hamsters induced to split their locomotor rhythms by exposure to constant light had asymmetric Per1 expression within cells of the middle SCN at 6 h before activity onset (AO) and in HCRT cells 9 h before and at AO. We did not observe evidence of lateralization of Per1 expression in the LC. We conclude that the SCN communicates circadian phase to HCRT cells via lateralized neural projections, and suggests that Per1 expression in the LC may be regulated by signals of a global or bilateral nature. PMID:23826226

Pubertally born neurons and glia are functionally integrated into limbic and hypothalamic circuits of the male Syrian hamster.

PubMed

Mohr, Margaret A; Sisk, Cheryl L

2013-03-19

During puberty, the brain goes through extensive remodeling, involving the addition of new neurons and glia to brain regions beyond the canonical neurogenic regions (i.e., dentate gyrus and olfactory bulb), including limbic and hypothalamic cell groups associated with sex-typical behavior. Whether these pubertally born cells become functionally integrated into neural circuits remains unknown. To address this question, we gave male Syrian hamsters daily injections of the cell birthdate marker bromodeoxyuridine throughout puberty (postnatal day 28-49). Half of the animals were housed in enriched environments with access to a running wheel to determine whether enrichment increased the survival of pubertally born cells compared with the control environment. At 4 wk after the last BrdU injection, animals were allowed to interact with a receptive female and were then killed 1 h later. Triple-label immunofluorescence for BrdU, the mature neuron marker neuronal nuclear antigen, and the astrocytic marker glial fibrillary acidic protein revealed that a proportion of pubertally born cells in the medial preoptic area, arcuate nucleus, and medial amygdala differentiate into either mature neurons or astrocytes. Double-label immunofluorescence for BrdU and the protein Fos revealed that a subset of pubertally born cells in these regions is activated during sociosexual behavior, indicative of their functional incorporation into neural circuits. Enrichment affected the survival and activation of pubertally born cells in a brain region-specific manner. These results demonstrate that pubertally born cells located outside of the traditional neurogenic regions differentiate into neurons and glia and become functionally incorporated into neural circuits that subserve sex-typical behaviors.

A novel regulatory element (E77) isolated from CHO-K1 genomic DNA enhances stable gene expression in Chinese hamster ovary cells.

PubMed

Kang, Shin-Young; Kim, Yeon-Gu; Kang, Seunghee; Lee, Hong Weon; Lee, Eun Gyo

2016-05-01

Vectors flanked by regulatory DNA elements have been used to generate stable cell lines with high productivity and transgene stability; however, regulatory elements in Chinese hamster ovary (CHO) cells, which are the most widely used mammalian cells in biopharmaceutical production, are still poorly understood. We isolated a novel gene regulatory element from CHO-K1 cells, designated E77, which was found to enhance the stable expression of a transgene. A genomic library was constructed by combining CHO-K1 genomic DNA fragments with a CMV promoter-driven GFP expression vector, and the E77 element was isolated by screening. The incorporation of the E77 regulatory element resulted in the generation of an increased number of clones with high expression, thereby enhancing the expression level of the transgene in the stable transfectant cell pool. Interestingly, the E77 element was found to consist of two distinct fragments derived from different locations in the CHO genome shotgun sequence. High and stable transgene expression was obtained in transfected CHO cells by combining these fragments. Additionally, the function of E77 was found to be dependent on its site of insertion and specific orientation in the vector construct. Our findings demonstrate that stable gene expression mediated by the CMV promoter in CHO cells may be improved by the isolated novel gene regulatory element E77 identified in the present study. © 2016 The Authors. Biotechnology Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In vivo SPECT imaging with 111In-DOTA-c(RGDfK) to detect early pancreatic cancer in a hamster pancreatic carcinogenesis model.

PubMed

Yoshimoto, Mitsuyoshi; Hayakawa, Takuya; Mutoh, Michihiro; Imai, Toshio; Tsuda, Keisuke; Kimura, Sadaaki; Umeda, Izumi O; Fujii, Hirofumi; Wakabayashi, Keiji

2012-05-01

Early detection of pancreatic cancer is key to overcoming its poor prognosis. α(v)β(3)-integrin is often overexpressed in pancreatic tumor cells, whereas it is scarcely expressed in normal pancreatic cells. In this study, we investigated the usefulness of SPECT imaging with (111)In-1,4,7,10-tetraazacylododecane-N,N',N″,N'''-tetraacetic acid-cyclo-(Arg-Gly-Asp-d-Phe-Lys) [(111)In-DOTA-c(RGDfK)], an imaging probe of α(v)β(3)-integrin, for the early detection of pancreatic cancer in a hamster pancreatic carcinogenesis model. Hamsters were subcutaneously injected with the pancreatic duct carcinogen N-nitrosobis(2-oxopropyl)amine to induce pancreatic cancer. N-nitrosobis(2-oxopropyl)amine-treated hamsters underwent in vivo SPECT with (111)In-DOTA-c(RGDfK). After imaging, the tumor-to-normal pancreatic tissue radioactivity ratios in excised pancreatic samples were measured with autoradiography (ARG) and compared with the immunopathologic findings for α(v)β(3)-integrin. In a mouse model in which inflammation was induced with turpentine, the uptake of (111)In-DOTA-c(RGDfK) in inflammatory regions was evaluated with ARG and compared with that of (18)F-FDG. (111)In-DOTA-c(RGDfK) was clearly visualized in pancreatic cancer lesions as small as 3 mm in diameter. ARG analysis revealed high tumor-to-normal pancreatic tissue radioactivity ratios (4.6 ± 1.0 [mean ± SD] in adenocarcinoma and 3.3 ± 1.4 in atypical hyperplasia). The uptake of (111)In-DOTA-c(RGDfK) strongly correlated with α(v)β(3)-integrin expression. In the inflammatory model, inflammation-to-muscle ratios for (18)F-FDG and (111)In-DOTA-c(RGDfK) were 8.37 ± 4.37 and 1.98 ± 0.60, respectively. These results imply that (111)In-DOTA-c(RGDfK) has a lower rate of false-positive tumor detection than (18)F-FDG. Our findings suggest that SPECT with (111)In-DOTA-c(RGDfK) has great potential for the early and accurate detection of pancreatic cancer.

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.

Optimization of gene delivery methods in Xenopus laevis kidney (A6) and Chinese hamster ovary (CHO) cell lines for heterologous expression of Xenopus inner ear genes

PubMed Central

Ramirez-Gordillo, Daniel; Trujillo-Provencio, Casilda; Knight, V. Bleu; Serrano, Elba E.

2014-01-01

The Xenopus inner ear provides a useful model for studies of hearing and balance because it shares features with the mammalian inner ear, and because amphibians are capable of regenerating damaged mechanosensory hair cells. The structure and function of many proteins necessary for inner ear function have yet to be elucidated and require methods for analysis. To this end, we seek to characterize Xenopus inner ear genes outside of the animal model through heterologous expression in cell lines. As part of this effort, we aimed to optimize physical (electroporation), chemical (lipid-mediated; Lipofectamine™ 2000, Metafectene® Pro), and biological (viral-mediated; BacMam virus Cellular Lights™ Tubulin-RFP) gene delivery methods in amphibian (Xenopus; A6) cells and mammalian (Chinese hamster ovary (CHO)) cells. We successfully introduced the commercially available pEGFP-N3, pmCherry-N1, pEYFP-Tubulin, and Cellular Lights™ Tubulin-RFP fluorescent constructs to cells and evaluated their transfection or transduction efficiencies using the three gene delivery methods. In addition, we analyzed the transfection efficiency of a novel construct synthesized in our laboratory by cloning the Xenopus inner ear calcium-activated potassium channel β1 subunit, then subcloning the subunit into the pmCherry-N1 vector. Every gene delivery method was significantly more effective in CHO cells. Although results for the A6 cell line were not statistically significant, both cell lines illustrate a trend towards more efficient gene delivery using viral-mediated methods; however the cost of viral transduction is also much higher. Our findings demonstrate the need to improve gene delivery methods for amphibian cells and underscore the necessity for a greater understanding of amphibian cell biology. PMID:21959846

The C-type Lectin Langerin Functions as a Receptor for Attachment and Infectious Entry of Influenza A Virus

PubMed Central

Ng, Wy Ching; Londrigan, Sarah L.; Nasr, Najla; Cunningham, Anthony L.; Turville, Stuart; Brooks, Andrew G.

2015-01-01

ABSTRACT It is well established that influenza A virus (IAV) attachment to and infection of epithelial cells is dependent on sialic acid (SIA) at the cell surface, although the specific receptors that mediate IAV entry have not been defined and multiple receptors may exist. Lec2 Chinese hamster ovary (CHO) cells are SIA deficient and resistant to IAV infection. Here we demonstrate that the expression of the C-type lectin receptor langerin in Lec2 cells (Lec2-Lg) rendered them permissive to IAV infection, as measured by replication of the viral genome, transcription of viral mRNA, and synthesis of viral proteins. Unlike SIA-dependent infection of parental CHO cells, IAV attachment and infection of Lec2-Lg cells was mediated via lectin-mediated recognition of mannose-rich glycans expressed by the viral hemagglutinin glycoprotein. Lec2 cells expressing endocytosis-defective langerin bound IAV efficiently but remained resistant to IAV infection, confirming that internalization via langerin was essential for infectious entry. Langerin-mediated infection of Lec2-Lg cells was pH and dynamin dependent, occurred via clathrin- and caveolin-mediated endocytic pathways, and utilized early (Rab5+) but not late (Rab7+) endosomes. This study is the first to demonstrate that langerin represents an authentic receptor that binds and internalizes IAV to facilitate infection. Moreover, it describes a unique experimental system to probe specific pathways and compartments involved in infectious entry following recognition of IAV by a single cell surface receptor. IMPORTANCE On the surface of host cells, sialic acid (SIA) functions as the major attachment factor for influenza A viruses (IAV). However, few studies have identified specific transmembrane receptors that bind and internalize IAV to facilitate infection. Here we identify human langerin as a transmembrane glycoprotein that can act as an attachment factor and a bone fide endocytic receptor for IAV infection. Expression of langerin by an SIA-deficient cell line resistant to IAV rendered cells permissive to infection. As langerin represented the sole receptor for IAV infection in this system, we have defined the pathways and compartments involved in infectious entry of IAV into cells following recognition by langerin. PMID:26468543

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.

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

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.

Nocturnal illumination maintains reproductive function and simulates the period-lengthening effect of constant light in the mature male Djungarian hamster (Phodopus sungorus)

NASA Technical Reports Server (NTRS)

Ferraro, J. S.

1990-01-01

Mature male Djungarian hamsters (Phodopus sungorus) were placed in individual light-tight, sound attenuated chambers and exposed to one of four lighting conditions for a duration of approximately seven weeks. The four lighting conditions were: constant light (LL); constant dark (DD); feedback lighting (LDFB; a condition that illuminates the cage in response to locomotor activity); or a feedback lighting neighbor control (LDFB NC; the animal receives the same light pattern as a paired animal in feedback lighting, but has no control over it). Exposure of hamsters to LL or LDFB produced significantly and similarly longer free-running periods of the locomotor activity rhythm than exposure of animals to DD. Hamsters exposed to LDFB NC did not free-run or entrain, but rather displayed "relative coordination". The paired testes and sex accessory glands weights suggest that in the Djungarian hamster, LL and LDFB exposed animals maintained reproductive function, whereas DD exposed animals did not. Animals exposed to LDFB NC had intermediate paired testes weights. Since several previous studies have demonstrated that short pulses of light, which are coincident with the subjective night, are photostimulatory, it is not surprising that LDFB maintained reproductive function in the mature Djungarian hamster. Feedback lighting, however, has been shown to be an insufficient stimulus to maintain reproductive function of mature male and female Syrian hamsters, and to the reproductive maturation of immature Djungarian hamsters. The results suggest that there may be slight, but significant differences in the way these two species interpret photoperiod, as well as a developmental change in the photoperiodic response of Djungarian hamsters.

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.

Effects of Synephrine and B-Phenethylamine on Human a-Adrenoceptor Subtypes

USDA-ARS?s Scientific Manuscript database

Synephrine and B-phenethylamine are structurally related to ephedrine. In this study, the effects of synephrine and B-phenethylamine are investigated on a-adrenoceptor (a-AR) subtypes expressed in human embroyonic kidney (HEK293) or Chinese hamster ovary (CHO) cells, and compared to that of 1R,2S-no...

Curcumin-3,4-Dichloro Phenyl Pyrazole (CDPP) overcomes curcumin's low bioavailability, inhibits adipogenesis and ameliorates dyslipidemia by activating reverse cholesterol transport.

PubMed

Gupta, Abhishek; Singh, Vinay Kumar; Kumar, Durgesh; Yadav, Pragya; Kumar, Santosh; Beg, Muheeb; Shankar, Kripa; Varshney, Salil; Rajan, Sujith; Srivastava, Ankita; Choudhary, Rakhi; Balaramnavar, Vishal M; Bhatta, Rabi; Tadigoppula, Narender; Gaikwad, Anil Nilkanth

2017-08-01

Adipocyte dysfunction, obesity and associated metabolic disorders are of prime healthcare concern worldwide. Among available medications, natural products and inspired molecules hold 40% space in clinically prescribed medicines. In queue, this study overcomes the drawback of curcumin's low bioavailability with potent anti-adipogenic and anti-dyslipidemic activity. To evaluate the role of CDPP on adipocyte differentiation, 3T3-L1 adipocytes were used as an in-vitro model. Flow cytometry was performed for cell cycle analysis. Syrian golden hamsters were used to study pharmacokinetic profile and dyslipidemic activity exhibited by CDPP. CDPP was found to be a potent inhibitor of adipogenesis in-vitro. It blocked mitotic clonal expansion by causing cell cycle arrest. CDPP showed marked improvement in gastrointestinal stability and bioavailability in-vivo as compared to curcumin. Administration of CDPP (100mg/kg) significantly improved HFD induced dyslipidemic profile in hamsters and activated reverse cholesterol transport machinery. CDPP could be used as a potential drug candidate against adipogenesis and dyslipidemia with enhanced gastrointestinal stability and bioavailability. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

Distinct functional characteristics of levocabastine sensitive rat neurotensin NT2 receptor expressed in Chinese hamster ovary cells.

PubMed

Yamada, M; Yamada, M; Lombet, A; Forgez, P; Rostène, W

1998-01-01

Neurotensin has been shown to produce pharmacological effects both in brain and periphery. Several of these effects are mediated by a high-affinity neurotensin NT1 receptor. On the other hand, a low-affinity levocabastine-sensitive neurotensin NT2 receptor was molecularly cloned from rodent brain recently. In this study, in contrast to NT1 receptor, levocabastine (a histamine H1 receptor antagonist) and SR48692 (an antagonist for NT1 receptor) strongly stimulated intracellular Ca2+ mobilization in transfected Chinese hamster ovary cells expressing rat NT2 receptor, thus acting as potent NT2 receptor. Furthermore, despite of their affinities for NT2 receptor, the Ca2+ responses to potent NT1 agonists, neurotensin or JMV449 ([Lys8-(CH2NH)-Lys9]Pro-Tyr-Ile-Leu, a peptidase resistant analogue of neurotensin) were much smaller than that observed with SR48692. These findings suggest that NT1 and NT2 receptors present distinct functional characteristics and that SR48692 may act as a potent agonist for NT2 receptor.

9 CFR 3.28 - Primary enclosures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Pigs and Hamsters Facilities and Operating Standards § 3.28 Primary enclosures. All primary enclosures for guinea pigs and hamsters shall conform to the following requirements: (a) General. (1) Primary enclosures shall be structurally sound and maintained in good repair to protect the guinea pigs and hamsters...

9 CFR 3.40 - Terminal facilities.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Pigs and Hamsters Transportation Standards § 3.40 Terminal facilities. No person subject to the Animal Welfare regulations shall commingle shipments of live guinea pigs or hamsters with inanimate cargo. All animal holding areas of a terminal facility where shipments of live guinea pigs or hamsters are...

9 CFR 3.31 - Sanitation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Pigs and Hamsters Animal Health and Husbandry Standards § 3.31 Sanitation. (a) Cleaning and sanitation... foods, or moisture condensation, the guinea pigs or hamsters shall be transferred to clean primary enclosures. (3) Prior to the introduction of guinea pigs or hamsters into empty primary enclosures previously...

9 CFR 3.28 - Primary enclosures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... for guinea pigs and hamsters shall conform to the following requirements: (a) General. (1) Primary enclosures shall be structurally sound and maintained in good repair to protect the guinea pigs and hamsters... be constructed and maintained so that the guinea pigs or hamsters contained therein have convenient...

9 CFR 3.28 - Primary enclosures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Pigs and Hamsters Facilities and Operating Standards § 3.28 Primary enclosures. All primary enclosures for guinea pigs and hamsters shall conform to the following requirements: (a) General. (1) Primary enclosures shall be structurally sound and maintained in good repair to protect the guinea pigs and hamsters...

9 CFR 3.31 - Sanitation.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Pigs and Hamsters Animal Health and Husbandry Standards § 3.31 Sanitation. (a) Cleaning and sanitation... foods, or moisture condensation, the guinea pigs or hamsters shall be transferred to clean primary enclosures. (3) Prior to the introduction of guinea pigs or hamsters into empty primary enclosures previously...

9 CFR 3.40 - Terminal facilities.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Pigs and Hamsters Transportation Standards § 3.40 Terminal facilities. No person subject to the Animal Welfare regulations shall commingle shipments of live guinea pigs or hamsters with inanimate cargo. All animal holding areas of a terminal facility where shipments of live guinea pigs or hamsters are...

9 CFR 3.40 - Terminal facilities.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Pigs and Hamsters Transportation Standards § 3.40 Terminal facilities. No person subject to the Animal Welfare regulations shall commingle shipments of live guinea pigs or hamsters with inanimate cargo. All animal holding areas of a terminal facility where shipments of live guinea pigs or hamsters are...

9 CFR 3.31 - Sanitation.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Pigs and Hamsters Animal Health and Husbandry Standards § 3.31 Sanitation. (a) Cleaning and sanitation... foods, or moisture condensation, the guinea pigs or hamsters shall be transferred to clean primary enclosures. (3) Prior to the introduction of guinea pigs or hamsters into empty primary enclosures previously...

9 CFR 3.40 - Terminal facilities.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Pigs and Hamsters Transportation Standards § 3.40 Terminal facilities. No person subject to the Animal Welfare regulations shall commingle shipments of live guinea pigs or hamsters with inanimate cargo. All animal holding areas of a terminal facility where shipments of live guinea pigs or hamsters are...

9 CFR 3.31 - Sanitation.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Pigs and Hamsters Animal Health and Husbandry Standards § 3.31 Sanitation. (a) Cleaning and sanitation... foods, or moisture condensation, the guinea pigs or hamsters shall be transferred to clean primary enclosures. (3) Prior to the introduction of guinea pigs or hamsters into empty primary enclosures previously...

High frequency stimulation of the entopeduncular nucleus sets the cortico-basal ganglia network to a new functional state in the dystonic hamster.

PubMed

Reese, René; Charron, Giselle; Nadjar, Agnès; Aubert, Incarnation; Thiolat, Marie-Laure; Hamann, Melanie; Richter, Angelika; Bezard, Erwan; Meissner, Wassilios G

2009-09-01

High frequency stimulation (HFS) of the internal pallidum is effective for the treatment of dystonia. Only few studies have investigated the effects of stimulation on the activity of the cortex-basal ganglia network. We here assess within this network the effect of entopeduncular nucleus (EP) HFS on the expression of c-Fos and cytochrome oxidase subunit I (COI) in the dt(sz)-hamster, a well-characterized model of paroxysmal dystonia. In dt(sz)-hamsters, we identified abnormal activity in motor cortex, basal ganglia and thalamus. These structures have already been linked to the pathophysiology of human dystonia. EP-HFS (i) increased striatal c-Fos expression in controls and dystonic hamsters and (ii) reduced thalamic c-Fos expression in dt(sz)-hamsters. EP-HFS had no effect on COI expression. The present results suggest that EP-HFS induces a new network activity state which may improve information processing and finally reduces the severity of dystonic attacks in dt(sz)-hamsters.

Hypothyroidism Affects D2 Receptor-mediated Breathing without altering D2 Receptor Expression

PubMed Central

Schlenker, Evelyn H.; Rio, Rodrigo Del; Schultz, Harold D.

2015-01-01

Bromocriptine depressed ventilation in air and D2 receptor expression in the nucleus tractus solitaries (NTS) in male hypothyroid hamsters. Here we postulated that in age- matched hypothyroid female hamsters, the pattern of D2 receptor modulation of breathing and D2 receptor expression would differ from those reported in hypothyroid males. In females hypothyroidism did not affect D2 receptor protein levels in the NTS, carotid bodies or striatum. Bromocriptine, but not carmoxirole (a peripheral D2 receptor agonist), increased oxygen consumption and body temperature in awake air-exposed hypothyroid female hamsters and stimulated their ventilation before and following exposure to hypoxia. Carmoxirole depressed frequency of breathing in euthyroid hamsters prior to, during and following hypoxia exposures and stimulated it in the hypothyroid hamsters following hypoxia. Although hypothyroidism did not affect expression of D2 receptors, it influenced central D2 modulation of breathing in a disparate manner relative to euthyroid hamsters. PMID:24434437

Hypothyroidism affects D2 receptor-mediated breathing without altering D2 receptor expression.

PubMed

Schlenker, Evelyn H; Del Rio, Rodrigo; Schultz, Harold D

2014-03-01

Bromocriptine depressed ventilation in air and D2 receptor expression in the nucleus tractus solitaries (NTS) in male hypothyroid hamsters. Here we postulated that in age-matched hypothyroid female hamsters, the pattern of D2 receptor modulation of breathing and D2 receptor expression would differ from those reported in hypothyroid males. In females hypothyroidism did not affect D2 receptor protein levels in the NTS, carotid bodies or striatum. Bromocriptine, but not carmoxirole (a peripheral D2 receptor agonist), increased oxygen consumption and body temperature in awake air-exposed hypothyroid female hamsters and stimulated their ventilation before and following exposure to hypoxia. Carmoxirole depressed frequency of breathing in euthyroid hamsters prior to, during and following hypoxia exposures and stimulated it in the hypothyroid hamsters following hypoxia. Although hypothyroidism did not affect expression of D2 receptors, it influenced central D2 modulation of breathing in a disparate manner relative to euthyroid hamsters. Copyright © 2014 Elsevier B.V. All rights reserved.

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

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.

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.

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.

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

Increased production of functional recombinant human clotting factor IX by baby hamster kidney cells engineered to overexpress VKORC1, the vitamin K 2,3-epoxide-reducing enzyme of the vitamin K cycle.

PubMed

Wajih, Nadeem; Hutson, Susan M; Owen, John; Wallin, Reidar

2005-09-09

Some recombinant vitamin K-dependent blood coagulation factors (factors VII, IX, and protein C) have become valuable pharmaceuticals in the treatment of bleeding complications and sepsis. Because of their vitamin K-dependent post-translational modification, their synthesis by eukaryotic cells is essential. The eukaryotic cell harbors a vitamin K-dependent gamma-carboxylation system that converts the proteins to gamma-carboxyglutamic acid-containing proteins. However, the system in eukaryotic cells has limited capacity, and cell lines overexpressing vitamin K-dependent clotting factors produce only a fraction of the recombinant proteins as fully gamma-carboxylated, physiologically competent proteins. In this work we have used recombinant human factor IX (r-hFIX)-producing baby hamster kidney (BHK) cells, engineered to stably overexpress various components of the gamma-carboxylation system of the cell, to determine whether increased production of functional r-hFIX can be accomplished. All BHK cell lines secreted r-hFIX into serum-free medium. Overexpression of gamma-carboxylase is shown to inhibit production of functional r-hFIX. On the other hand, cells overexpressing VKORC1, the reduced vitamin K cofactor-producing enzyme of the vitamin K-dependent gamma-carboxylation system, produced 2.9-fold more functional r-hFIX than control BHK cells. The data are consistent with the notion that VKORC1 is the rate-limiting step in the system and is a key regulatory protein in synthesis of active vitamin K-dependent proteins. The data suggest that overexpression of VKORC1 can be utilized for increased cellular production of recombinant vitamin K-dependent proteins.

Real-time quantitative PCR for retrovirus-like particle quantification in CHO cell culture.

PubMed

de Wit, C; Fautz, C; Xu, Y

2000-09-01

Chinese hamster ovary (CHO) cells have been widely used to manufacture recombinant proteins intended for human therapeutic uses. Retrovirus-like particles, which are apparently defective and non-infectious, have been detected in all CHO cells by electron microscopy (EM). To assure viral safety of CHO cell-derived biologicals, quantification of retrovirus-like particles in production cell culture and demonstration of sufficient elimination of such retrovirus-like particles by the down-stream purification process are required for product market registration worldwide. EM, with a detection limit of 1x10(6) particles/ml, is the standard retrovirus-like particle quantification method. The whole process, which requires a large amount of sample (3-6 litres), is labour intensive, time consuming, expensive, and subject to significant assay variability. In this paper, a novel real-time quantitative PCR assay (TaqMan assay) has been developed for the quantification of retrovirus-like particles. Each retrovirus particle contains two copies of the viral genomic particle RNA (pRNA) molecule. Therefore, quantification of retrovirus particles can be achieved by quantifying the pRNA copy number, i.e. every two copies of retroviral pRNA is equivalent to one retrovirus-like particle. The TaqMan assay takes advantage of the 5'-->3' exonuclease activity of Taq DNA polymerase and utilizes the PRISM 7700 Sequence Detection System of PE Applied Biosystems (Foster City, CA, U.S.A.) for automated pRNA quantification through a dual-labelled fluorogenic probe. The TaqMan quantification technique is highly comparable to the EM analysis. In addition, it offers significant advantages over the EM analysis, such as a higher sensitivity of less than 600 particles/ml, greater accuracy and reliability, higher sample throughput, more flexibility and lower cost. Therefore, the TaqMan assay should be used as a substitute for EM analysis for retrovirus-like particle quantification in CHO cell-based production system. Copyright 2000 The International Association for Biologicals.

Oxidative Stress in Mammalian Cells Impinges on the Cysteines Redox State of Human XRCC3 Protein and on Its Cellular Localization

PubMed Central

Girard, Pierre-Marie; Graindorge, Dany; Smirnova, Violetta; Rigolet, Pascal; Francesconi, Stefania; Scanlon, Susan; Sage, Evelyne

2013-01-01

In vertebrates, XRCC3 is one of the five Rad51 paralogs that plays a central role in homologous recombination (HR), a key pathway for maintaining genomic stability. While investigating the potential role of human XRCC3 (hXRCC3) in the inhibition of DNA replication induced by UVA radiation, we discovered that hXRCC3 cysteine residues are oxidized following photosensitization by UVA. Our in silico prediction of the hXRCC3 structure suggests that 6 out of 8 cysteines are potentially accessible to the solvent and therefore potentially exposed to ROS attack. By non-reducing SDS-PAGE we show that many different oxidants induce hXRCC3 oxidation that is monitored in Chinese hamster ovarian (CHO) cells by increased electrophoretic mobility of the protein and in human cells by a slight decrease of its immunodetection. In both cell types, hXRCC3 oxidation was reversed in few minutes by cellular reducing systems. Depletion of intracellular glutathione prevents hXRCC3 oxidation only after UVA exposure though depending on the type of photosensitizer. In addition, we show that hXRCC3 expressed in CHO cells localizes both in the cytoplasm and in the nucleus. Mutating all hXRCC3 cysteines to serines (XR3/S protein) does not affect the subcellular localization of the protein even after exposure to camptothecin (CPT), which typically induces DNA damages that require HR to be repaired. However, cells expressing mutated XR3/S protein are sensitive to CPT, thus highlighting a defect of the mutant protein in HR. In marked contrast to CPT treatment, oxidative stress induces relocalization at the chromatin fraction of both wild-type and mutated protein, even though survival is not affected. Collectively, our results demonstrate that the DNA repair protein hXRCC3 is a target of ROS induced by environmental factors and raise the possibility that the redox environment might participate in regulating the HR pathway. PMID:24116071

9 CFR 3.30 - Watering.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Pigs and Hamsters Animal Health and Husbandry Standards § 3.30 Watering. Unless food supplements consumed by guinea pigs or hamsters supply them with their normal water requirements, potable water shall... containers used for dispensing water to guinea pigs or hamsters shall be so placed in or attached to the...

9 CFR 3.26 - Facilities, indoor.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Pigs and Hamsters Facilities and Operating Standards § 3.26 Facilities, indoor. (a) Heating. Indoor housing facilities for guinea pigs or hamsters shall be sufficiently heated when necessary to protect the... pigs or hamsters shall be adequately ventilated to provide for the health and comfort of the animals at...

9 CFR 3.31 - Sanitation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... foods, or moisture condensation, the guinea pigs or hamsters shall be transferred to clean primary enclosures. (3) Prior to the introduction of guinea pigs or hamsters into empty primary enclosures previously...) Primary enclosures for guinea pigs or hamsters shall be sanitized by washing them with hot water (180 °F...

9 CFR 3.29 - Feeding.

Code of Federal Regulations, 2010 CFR

2010-01-01

... STANDARDS Specifications for the Humane Handling, Care, Treatment, and Transportation of Guinea Pigs and Hamsters Animal Health and Husbandry Standards § 3.29 Feeding. (a) Guinea pigs and hamsters shall be fed... the normal daily requirements for the condition and size of the guinea pig or hamster. (b) Food...

9 CFR 3.26 - Facilities, indoor.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Pigs and Hamsters Facilities and Operating Standards § 3.26 Facilities, indoor. (a) Heating. Indoor housing facilities for guinea pigs or hamsters shall be sufficiently heated when necessary to protect the... pigs or hamsters shall be adequately ventilated to provide for the health and comfort of the animals at...

9 CFR 3.30 - Watering.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Pigs and Hamsters Animal Health and Husbandry Standards § 3.30 Watering. Unless food supplements consumed by guinea pigs or hamsters supply them with their normal water requirements, potable water shall... containers used for dispensing water to guinea pigs or hamsters shall be so placed in or attached to the...

9 CFR 3.30 - Watering.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Pigs and Hamsters Animal Health and Husbandry Standards § 3.30 Watering. Unless food supplements consumed by guinea pigs or hamsters supply them with their normal water requirements, potable water shall... containers used for dispensing water to guinea pigs or hamsters shall be so placed in or attached to the...

9 CFR 3.30 - Watering.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Pigs and Hamsters Animal Health and Husbandry Standards § 3.30 Watering. Unless food supplements consumed by guinea pigs or hamsters supply them with their normal water requirements, potable water shall... containers used for dispensing water to guinea pigs or hamsters shall be so placed in or attached to the...

9 CFR 3.26 - Facilities, indoor.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Pigs and Hamsters Facilities and Operating Standards § 3.26 Facilities, indoor. (a) Heating. Indoor housing facilities for guinea pigs or hamsters shall be sufficiently heated when necessary to protect the... pigs or hamsters shall be adequately ventilated to provide for the health and comfort of the animals at...

9 CFR 3.26 - Facilities, indoor.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Pigs and Hamsters Facilities and Operating Standards § 3.26 Facilities, indoor. (a) Heating. Indoor housing facilities for guinea pigs or hamsters shall be sufficiently heated when necessary to protect the... pigs or hamsters shall be adequately ventilated to provide for the health and comfort of the animals at...

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...

Contribution of X-Ray Repair Complementing Defective Repair in Chinese Hamster Cells 3 (XRCC3) Genotype to Leiomyoma Risk.

PubMed

Chang, Wen-Shin; Tsai, Chia-Wen; Wang, Ju-Yu; Ying, Tsung-Ho; Hsiao, Tsan-Seng; Chuang, Chin-Liang; Yueh, Te-Cheng; Liao, Cheng-Hsi; Hsu, Chin-Mu; Liu, Shih-Ping; Gong, Chi-Li; Tsai, Chang-Hai; Bau, Da-Tian

2015-09-01

The present study aimed at investigating whether X-ray repair cross complementing protein 3 (XRCC3) genotype may serve as a useful marker for detecting leiomyoma and predicting risk. A total of 640 women (166 patients with leiomyoma and 474 healthy controls) were examined for their XRCC3 rs1799794, rs45603942, rs861530, rs3212057, rs1799796, rs861539, rs28903081 genotype. The distributions of genotypic and allelic frequencies between the two groups were compared. The results showed that the CT and TT genotypes of XRCC3 rs861539 were associated with increased leiomyoma risk (odds ratio=2.19, 95% confidence interval=1.23-3.90; odds ratio=3.72, 95% confidence interval=1.23-11.26, respectively). On allelic frequency analysis, we found a significant difference in the distribution of the T allelic frequency of the XRCC3 rs861539 (p=5.88 × 10(-5)). None of the other six single nucleotide polymorphisms were associated with altered leiomyoma susceptibility. The T allele (CT and TT genotypes) of XRCC3 rs861539 contributes to increased risk of leiomyoma among Taiwanese women and may serve as a early detection and predictive marker. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

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 nervous system pathology. PMID:27812087

Dietary turmeric modulates DMBA-induced p21{sup ras}, MAP kinases and AP-1/NF-{kappa}B pathway to alter cellular responses during hamster buccal pouch carcinogenesis

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

Garg, Rachana; Ingle, Arvind; Maru, Girish

2008-11-01

The chemopreventive efficacy of turmeric has been established in experimental systems. However, its mechanism(s) of action are not fully elucidated in vivo. The present study investigates the mechanism of turmeric-mediated chemoprevention in 7,12-dimethylbenz(a)anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis at 2, 4, 6, 10 and 12 weeks. Dietary turmeric (1%) led to decrease in DMBA-induced tumor burden and multiplicity, and enhanced the latency period in parallel, to its modulatory effects on oncogene products and various cellular responses during HBP tumorigenesis. DMBA-induced expression of ras oncogene product, p21 and downstream target, the mitogen-activated protein kinases were significantly decreased by turmeric duringmore » HBP carcinogenesis. Turmeric also diminished the DMBA-induced mRNA expression of proto-oncogenes (c-jun, c-fos) and NF-{kappa}B, leading to decreased protein levels and in further attenuation of DMBA-induced AP-1/NF-{kappa}B DNA-binding in the buccal pouch nuclear extracts. Besides, buccal pouch of hamsters receiving turmeric diet showed significant alterations in DMBA-induced effects: (a) decrease in cell proliferation (diminished PCNA and Bcl2 expression), (b) enhanced apoptosis (increased expression of Bax, caspase-3 and apoptotic index), (c) decrease in inflammation (levels of Cox-2, the downstream target of AP-1/NF-{kappa}B, and PGE2) and (d) aberrant expression of differentiation markers, the cytokeratins (1, 5, 8, and 18). Together, the protective effects of dietary turmeric converge on augmenting apoptosis of the initiated cells and decreasing cell proliferation in DMBA-treated animals, which in turn, is reflected in decreased tumor burden, multiplicity and enhanced latency period. Some of these biomarkers are likely to be helpful in monitoring clinical trials and evaluating drug effect measurements.« less

Quantitative Detection and Biological Propagation of Scrapie Seeding Activity In Vitro Facilitate Use of Prions as Model Pathogens for Disinfection

PubMed Central

Pritzkow, Sandra; Wagenführ, Katja; Daus, Martin L.; Boerner, Susann; Lemmer, Karin; Thomzig, Achim; Mielke, Martin; Beekes, Michael

2011-01-01

Prions are pathogens with an unusually high tolerance to inactivation and constitute a complex challenge to the re-processing of surgical instruments. On the other hand, however, they provide an informative paradigm which has been exploited successfully for the development of novel broad-range disinfectants simultaneously active also against bacteria, viruses and fungi. Here we report on the development of a methodological platform that further facilitates the use of scrapie prions as model pathogens for disinfection. We used specifically adapted serial protein misfolding cyclic amplification (PMCA) for the quantitative detection, on steel wires providing model carriers for decontamination, of 263K scrapie seeding activity converting normal protease-sensitive into abnormal protease-resistant prion protein. Reference steel wires carrying defined amounts of scrapie infectivity were used for assay calibration, while scrapie-contaminated test steel wires were subjected to fifteen different procedures for disinfection that yielded scrapie titre reductions of ≤101- to ≥105.5-fold. As confirmed by titration in hamsters the residual scrapie infectivity on test wires could be reliably deduced for all examined disinfection procedures, from our quantitative seeding activity assay. Furthermore, we found that scrapie seeding activity present in 263K hamster brain homogenate or multiplied by PMCA of scrapie-contaminated steel wires both triggered accumulation of protease-resistant prion protein and was further propagated in a novel cell assay for 263K scrapie prions, i.e., cerebral glial cell cultures from hamsters. The findings from our PMCA- and glial cell culture assays revealed scrapie seeding activity as a biochemically and biologically replicative principle in vitro, with the former being quantitatively linked to prion infectivity detected on steel wires in vivo. When combined, our in vitro assays provide an alternative to titrations of biological scrapie infectivity in animals that substantially facilitates the use of prions as potentially highly indicative test agents in the search for novel broad-range disinfectants. PMID:21647368

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

Recombinant interferon-gamma secreted by Chinese hamster ovary-320 cells cultivated in suspension in protein-free media is protected against extracellular proteolysis by the expression of natural protease inhibitors and by the addition of plant protein hydrolysates to the culture medium.

PubMed

Mols, J; Peeters-Joris, C; Wattiez, R; Agathos, S N; Schneider, Y-J

2005-01-01

Biosafety requirements increasingly restrict the cultivation of mammalian cells producing therapeutic glycoproteins to conditions that are devoid of any compound of animal origin. On cultivation in serum-free media, the proteases inhibitors, usually found in serum, cannot protect secreted recombinant proteins against unwanted endogenous proteolysis. Chinese hamster ovary (CHO) cells, secreting recombinant human interferon-gamma (CHO-320 cell line) and cultivated in suspension in an original protein-free medium, expressed at least two members of the matrix metalloproteinases (MMP), either at the cell surface (proMMP-14 and MMP-14) or secreted (proMMP-9). In addition, tissue- and urinary-type plasminogen activators were also secreted in such culture conditions. At the cell surface, dipeptidyl peptidase IV and tripeptidyl peptidase II (TPPII) activities were also detected, and their activities decreased during time course of batch cultures. The proteolytic activities of these proteins were counterbalanced by (1) their expression as zymogens (proMMP-9, proMMP-14), (2) the expression of their natural inhibitors, tissue inhibitors of metalloproteinases-1 and -2 and plasminogen activator inhibitor-1 (PAI-1), or (3) the addition of plant protein hydrolysates to the culture medium, acting as a nonspecific source of TPPII inhibitors. This study points out that, even in protein-free media, recombinant proteins secreted by CHO cells are actively protected against physiological and unwanted extracellular proteolysis either by endogenous or by exogenous inhibitors.

Very High Density of Chinese Hamster Ovary Cells in Perfusion by Alternating Tangential Flow or Tangential Flow Filtration in WAVE Bioreactor™—Part II: Applications for Antibody Production and Cryopreservation

PubMed Central

Clincke, Marie-Françoise; Mölleryd, Carin; Samani, Puneeth K; Lindskog, Eva; Fäldt, Eric; Walsh, Kieron; Chotteau, Véronique

2013-01-01

A high cell density perfusion process of monoclonal antibody (MAb) producing Chinese hamster ovary (CHO) cells was developed in disposable WAVE Bioreactor™ using external hollow fiber (HF) filter as cell separation device. Tangential flow filtration (TFF) and alternating tangential flow (ATF) systems were compared and process applications of high cell density perfusion were studied here: MAb production and cryopreservation. Operations by perfusion using microfiltration (MF) or ultrafiltration (UF) with ATF or TFF and by fed-batch were compared. Cell densities higher than 108 cells/mL were obtained using UF TFF or UF ATF. The cells produced comparable amounts of MAb in perfusion by ATF or TFF, MF or UF. MAbs were partially retained by the MF using ATF or TFF but more severely using TFF. Consequently, MAbs were lost when cell broth was discarded from the bioreactor in the daily bleeds. The MAb cell-specific productivity was comparable at cell densities up to 1.3 × 108 cells/mL in perfusion and was comparable or lower in fed-batch. After 12 days, six times more MAbs were harvested using perfusion by ATF or TFF with MF or UF, compared to fed-batch and 28× more in a 1-month perfusion at 108 cells/mL density. Pumping at a recirculation rate up to 2.75 L/min did not damage the cells with the present TFF settings with HF short circuited. Cell cryopreservation at 0.5 × 108 and 108 cells/mL was performed using cells from a perfusion run at 108 cells/mL density. Cell resuscitation was very successful, showing that this system was a reliable process for cell bank manufacturing. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:768–777, 2013 PMID:23436783

Effects of oral administration of different doses of purified micronized flavonoid fraction on microvascular reactivity after ischaemia/reperfusion in the hamster cheek pouch

PubMed Central

Bouskela, E; Cyrino, F Z G A; Lerond, L

1997-01-01

The effects of a purified micronized flavonoid fraction (S5682) on mean internal diameter and blood flow of arterioles and venules, as well as the functional capillary density (FCD) were evaluated in the hamster cheek pouch microvasculature before and after 90 min of total ischaemia. Male hamsters were treated for ten days, twice a day, with oral doses of S5682 (5, 20, 80 and 160 mg kg−1 day−1) or placebo (10% lactose solution). The cheek pouch preparation was placed under an intravital microscope coupled to a closed circuit TV system. Local ischaemia was obtained by a cuff mounted around the neck of the everted pouch where it leaves the mouth of the hamster. Measurements were performed before ischaemia, at the onset of reperfusion and 10, 20, 30, 45 and 60 min thereafter. Diameters were measured by means of an image shearing device. Red blood cell (RBC) velocity was analysed by use of the dual-slit photometric technique. Blood flow was calculated from diameters and RBC velocities. FCD, defined as the number of capillaries with flowing blood per field of observation, was also assessed. During reperfusion, placebo-treated animals showed a significant vasodilatation, a decrease in blood flow and FCD and S5682-treated animals showed a clear trend, dose-dependent, towards maintaining these parameters closer to the value found before ischaemia. In conclusion, our results indicate that S5682 improves the microvascular reactivity and FCD after ischaemia/reperfusion. These data suggest that S5682 could function as an antioxidant, which may explain its beneficial therapeutic effect in chronic venous insufficiency where oxidative stress is involved in the pathological mechanism. PMID:9422805

Localization and treatment of transformed tissues using the photodynamic sensitizer 2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a.

PubMed

Furukawa, K; Yamamoto, H; Crean, D H; Kato, H; Mang, T S

1996-01-01

Photofrin is the photosensitizer currently used in most clinical trials examining the efficacy of photodynamic therapy (PDT) for the treatment and/or palliation of neoplasia. Although this drug has been shown to be efficacious in many of these trials, it possesses less than ideal qualities for use in a systemically administered photosensitizer. A new photosensitizer, 2-[l-hexyloxyethyl]-2-devinyl pyropheophorbide-a (HPPH), was developed for PDT. HPPH possesses more rapid clearance from skin and greater cytotoxicity per drug dose than Photofrin. The aims of this study were to: (1) examine the uptake and retention of HPPH in tissues undergoing malignant transformation using laser-induced fluorescence, and (2) evaluate the efficacy of HPPH and 665 nm light in treating carcinogen-induced tumors of the hamster buccal cheek pouch. The model of tissue transformation was the carcinogen (9,10-dimethyl-1, 2-benzanthracene)-induced premalignant and malignant lesions of the hamster buccal cheek pouch. Following induction of the specific transformation stages, hamsters were injected intraperitoneally with 0.5 mg/kg HPPH. Subsequently, the buccal mucosa was examined for fluorescence at various times up to 72 hours after photosensitizer injection. Uptake studies of HPPH showed highest fluorescence levels in tissues 48 hours after HPPH injection. Fluorescence levels of tissues increased significantly as follows. Normal < dysplasia < papillomas < squamous cell carcinomas. Carcinogen-induced tumors in 14 hamsters were treated with surface illuminations of red light (665 nm) via fiber optics coupled to an argon-ion pumped dye laser 48 hours after intraperitoneal injection with either 0.5 or 1.0 mg/kg HPPH. Complete necrosis of tumor tissues 7 days following PDT was observed in 57% (4/7) with 0.5 mg/kg and 86% (6/7) with 1.0 mg/kg HPPH.

Modelling person-to-person transmission in an Enterovirus A71 orally infected hamster model of hand-foot-and-mouth disease and encephalomyelitis.

PubMed

Phyu, Win Kyaw; Ong, Kien Chai; Wong, Kum Thong

2017-07-12

Enterovirus A71 (EV-A71) causes hand-foot-and-mouth disease (HFMD), which may be complicated by fatal encephalomyelitis. Although fecal-oral or oral-oral routes are important in person-to-person transmission, how viral shedding and exposure may predispose individuals to infection remains unknown. We investigated person-to-person transmission by using a model of HFMD and encephalomyelitis based on EV-A71 oral infection of 2-week-old hamsters. Animals (index animals) infected with 10 4 50% cell culture infective doses of virus uniformly developed severe disease four days post-infection (dpi), whereas littermate contacts developed severe disease after six to seven days of exposure to index animals. Virus was detected in oral washes and feces at 3-4 dpi in index animals and at three to eight days after exposure to index animals in littermate contact animals. In a second experiment, non-littermate contact animals exposed for 8 or 12 h to index animals developed the disease six and four days post-exposure, respectively. Tissues from killed index and contact animals, studied by light microscopy, immunohistochemistry and in situ hybridization, exhibited mild inflammatory lesions and/or viral antigens/RNA in the squamous epithelia of the oral cavity, tongue, paws, skin, esophagus, gastric epithelium, salivary glands, lacrimal glands, central nervous system neurons, muscles (skeletal, cardiac and smooth muscles) and liver. Orally shed viruses were probably derived from infected oral mucosa and salivary glands, whereas fecal viruses may have derived from these sites as well as from esophageal and gastric epithelia. Asymptomatic seroconversion in exposed mother hamsters was demonstrated. Our hamster model should be useful in studying person-to-person EV-A71 transmission and how drugs and vaccines may interrupt transmission.

Modelling person-to-person transmission in an Enterovirus A71 orally infected hamster model of hand-foot-and-mouth disease and encephalomyelitis

PubMed Central

Phyu, Win Kyaw; Ong, Kien Chai; Wong, Kum Thong

2017-01-01

Enterovirus A71 (EV-A71) causes hand-foot-and-mouth disease (HFMD), which may be complicated by fatal encephalomyelitis. Although fecal–oral or oral–oral routes are important in person-to-person transmission, how viral shedding and exposure may predispose individuals to infection remains unknown. We investigated person-to-person transmission by using a model of HFMD and encephalomyelitis based on EV-A71 oral infection of 2-week-old hamsters. Animals (index animals) infected with 104 50% cell culture infective doses of virus uniformly developed severe disease four days post-infection (dpi), whereas littermate contacts developed severe disease after six to seven days of exposure to index animals. Virus was detected in oral washes and feces at 3–4 dpi in index animals and at three to eight days after exposure to index animals in littermate contact animals. In a second experiment, non-littermate contact animals exposed for 8 or 12 h to index animals developed the disease six and four days post-exposure, respectively. Tissues from killed index and contact animals, studied by light microscopy, immunohistochemistry and in situ hybridization, exhibited mild inflammatory lesions and/or viral antigens/RNA in the squamous epithelia of the oral cavity, tongue, paws, skin, esophagus, gastric epithelium, salivary glands, lacrimal glands, central nervous system neurons, muscles (skeletal, cardiac and smooth muscles) and liver. Orally shed viruses were probably derived from infected oral mucosa and salivary glands, whereas fecal viruses may have derived from these sites as well as from esophageal and gastric epithelia. Asymptomatic seroconversion in exposed mother hamsters was demonstrated. Our hamster model should be useful in studying person-to-person EV-A71 transmission and how drugs and vaccines may interrupt transmission. PMID:28698666

Glass fibers and vapor phase components of cigarette smoke as cofactors in experimental respiratory tract carcinogenesis.

PubMed

Feron, V J; Kuper, C F; Spit, B J; Reuzel, P G; Woutersen, R A

1985-01-01

Syrian golden hamsters were given intratracheal instillations of glass fibers with or without BP suspended in saline, once a fortnight for 52 weeks; the experiment was terminated at week 85. No tumors of the respiratory tract were observed in hamsters treated with glass fibers alone. There was no indication that glass fibers enhanced the development of respiratory tract tumors induced by BP. In another study Syrian golden hamsters were exposed to fresh air or to a mixture of 4 major vapor phase components of cigarette smoke, viz. isoprene (800----700 ppm), methyl chloride (1000----900 ppm), methyl nitrite (200----190 ppm) and acetaldehyde (1400----1200 ppm) for a period of at most 23 months. Some of the animals were also given repeated intratracheal instillations of BP or norharman in saline. Laryngeal tumors were found in 7/31 male and 6/32 female hamsters exposed only to the vapor mixture, whereas no laryngeal tumors occurred in controls. The tumor response of the larynx most probably has to be ascribed entirely to the action of acetaldehyde. Simultaneous treatment with norharman or BP did not affect the tumor response of the larynx. Acetaldehyde may occur in the vapor phase of cigarette smoke at levels up to 2000 ppm. Chronic inhalation exposure of rats to acetaldehyde at levels of 0 (controls), 750, 1500 or 3000----1000 ppm resulted in a high incidence of nasal carcinomas, both squamous cell carcinomas of the respiratory epithelium and adenocarcinomas of the olfactory epithelium. It was discussed that acetaldehyde may significantly contribute to the induction of bronchogenic cancer by cigarette smoke in man. No evidence was obtained for a role of isoprene, methyl chloride or methyl nitrite in the induction of lung cancer by cigarette smoke.

Photonic crystal fibre enables short-wavelength two-photon laser scanning fluorescence microscopy with fura-2

NASA Astrophysics Data System (ADS)

McConnell, Gail; Riis, Erling

2004-10-01

We report on a novel and compact reliable laser source capable of short-wavelength two-photon laser scanning fluorescence microscopy based on soliton self-frequency shift effects in photonic crystal fibre. We demonstrate the function of the system by performing two-photon microscopy of smooth muscle cells and cardiac myocytes from the rat pulmonary vein and Chinese hamster ovary cells loaded with the fluorescent calcium indicator fura-2/AM.

Mechanism of NO-mediated oxidative and nitrative DNA damage in hamsters infected with Opisthorchis viverrini: a model of inflammation-mediated carcinogenesis.

PubMed

Pinlaor, Somchai; Hiraku, Yusuke; Ma, Ning; Yongvanit, Puangrat; Semba, Reiji; Oikawa, Shinji; Murata, Mariko; Sripa, Banchob; Sithithaworn, Paiboon; Kawanishi, Shosuke

2004-09-01

Inflammation mediated by infection is an important factor causing carcinogenesis. Opisthorchis viverrini (OV) infection is a risk factor of cholangiocarcinoma (CHCA), probably through chronic inflammation. Formation of 8-nitroguanine and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), and expression of inducible nitric oxide synthase (iNOS) and heme oxygenase-1 (HO-1) were assessed in the liver of hamsters infected with OV. We newly produced specific anti-8-nitroguanine antibody without cross-reaction. Double immunofluorescence staining revealed that 8-oxodG and 8-nitroguanine were formed mainly in the same inflammatory cells and epithelium of bile ducts from day 7 and showed the strongest immunoreactivity on days 21 and 30, respectively. It is noteworthy that 8-oxodG and 8-nitroguanine still remained in epithelium of bile ducts on day 180, although amount of alanine aminotransferase activity returned to normal level. A time course of 8-nitroguanine was associated with iNOS expression. Furthermore, this study demonstrated that HO-1 expression and subsequent iron accumulation may be involved in enhancement of oxidative DNA damage in epithelium of small bile ducts. In conclusion, nitrative and oxidative DNA damage via iNOS expression in hamsters infected with OV may participate in CHCA carcinogenesis.

Astaxanthin Inhibits JAK/STAT-3 Signaling to Abrogate Cell Proliferation, Invasion and Angiogenesis in a Hamster Model of Oral Cancer

PubMed Central

Kowshik, J.; Baba, Abdul Basit; Giri, Hemant; Deepak Reddy, G.; Dixit, Madhulika; Nagini, Siddavaram

2014-01-01

Identifying agents that inhibit STAT-3, a cytosolic transcription factor involved in the activation of various genes implicated in tumour progression is a promising strategy for cancer chemoprevention. In the present study, we investigated the effect of dietary astaxanthin on JAK-2/STAT-3 signaling in the 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis model by examining the mRNA and protein expression of JAK/STAT-3 and its target genes. Quantitative RT-PCR, immunoblotting and immunohistochemical analyses revealed that astaxanthin supplementation inhibits key events in JAK/STAT signaling especially STAT-3 phosphorylation and subsequent nuclear translocation of STAT-3. Furthermore, astaxanthin downregulated the expression of STAT-3 target genes involved in cell proliferation, invasion and angiogenesis, and reduced microvascular density, thereby preventing tumour progression. Molecular docking analysis confirmed inhibitory effects of astaxanthin on STAT signaling and angiogenesis. Cell culture experiments with the endothelial cell line ECV304 substantiated the role of astaxanthin in suppressing angiogenesis. Taken together, our data provide substantial evidence that dietary astaxanthin prevents the development and progression of HBP carcinomas through the inhibition of JAK-2/STAT-3 signaling and its downstream events. Thus, astaxanthin that functions as a potent inhibitor of tumour development and progression by targeting JAK/STAT signaling may be an ideal candidate for cancer chemoprevention. PMID:25296162

9 CFR 3.35 - Consignments to carriers and intermediate handlers.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.35 Consignments to... pig or hamster presented by any dealer, research facility, exhibitor, operator of an auction sale, or... for transportation or transport, in commerce any live guinea pig or hamster in a primary enclosure...

9 CFR 113.103 - Leptospira Canicola Bacterin.

Code of Federal Regulations, 2011 CFR

2011-01-01

... young adult hamsters, each weighing 50 to 90 grams, with 0.25 ml of the diluted bacterin either... least 10 but not more than 12 additional hamsters from the same group as unvaccinated controls. (3... intraperitoneally with a suspension of virulent Leptospira canicola organisms, using a dose of 10-10,000 hamster...

9 CFR 3.39 - Care in transit.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Pigs and Hamsters Transportation Standards § 3.39 Care in transit. (a) During surface transportation... pigs or hamsters as frequently as circumstances may dictate, but not less than once every 4 hours, to... any of the live guinea pigs or hamsters are in obvious physical distress and to provide any needed...

9 CFR 113.103 - Leptospira Canicola Bacterin.

Code of Federal Regulations, 2010 CFR

2010-01-01

... young adult hamsters, each weighing 50 to 90 grams, with 0.25 ml of the diluted bacterin either... least 10 but not more than 12 additional hamsters from the same group as unvaccinated controls. (3... intraperitoneally with a suspension of virulent Leptospira canicola organisms, using a dose of 10-10,000 hamster...

9 CFR 3.26 - Facilities, indoor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... housing facilities for guinea pigs or hamsters shall be sufficiently heated when necessary to protect the... facilities for guinea pigs or hamsters shall have ample light, by natural or artificial means, or both, of.... Primary enclosures shall be so placed as to protect the guinea pigs or hamsters from excessive...

9 CFR 3.39 - Care in transit.

Code of Federal Regulations, 2010 CFR

2010-01-01

... any of the live guinea pigs or hamsters are in obvious physical distress and to provide any needed veterinary care as soon as possible. When transported by air, live guinea pigs and hamsters shall be visually... during flight, the carrier shall visually observe the live guinea pigs or hamsters whenever loaded and...

9 CFR 3.35 - Consignments to carriers and intermediate handlers.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.35 Consignments to... for transportation or transport, in commerce any live guinea pig or hamster in a primary enclosure... it cannot reasonably be expected to contain the live guinea pig or hamster without causing suffering...

9 CFR 3.39 - Care in transit.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Pigs and Hamsters Transportation Standards § 3.39 Care in transit. (a) During surface transportation... pigs or hamsters as frequently as circumstances may dictate, but not less than once every 4 hours, to... any of the live guinea pigs or hamsters are in obvious physical distress and to provide any needed...

9 CFR 3.39 - Care in transit.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Pigs and Hamsters Transportation Standards § 3.39 Care in transit. (a) During surface transportation... pigs or hamsters as frequently as circumstances may dictate, but not less than once every 4 hours, to... any of the live guinea pigs or hamsters are in obvious physical distress and to provide any needed...

9 CFR 3.35 - Consignments to carriers and intermediate handlers.

Code of Federal Regulations, 2014 CFR

2014-01-01

..., and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.35 Consignments to... pig or hamster presented by any dealer, research facility, exhibitor, operator of an auction sale, or... for transportation or transport, in commerce any live guinea pig or hamster in a primary enclosure...