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1.
Biotechnol Biofuels ; 11: 67, 2018.
Article in English | MEDLINE | ID: mdl-29563970

ABSTRACT

BACKGROUND: Energy crops including Miscanthus provide a storable, portable energy source which can be used to complement a wide range of products and energy generation systems. Miscanthus is predominantly used in Europe as a combustion material for electricity generation but also has the potential for biochemical conversion due to its high yield and low-nutrient requirements. The ratio of holocellulose (hemicellulose and cellulose combined) to acid detergent lignin (H:L) within the senesced material has previously been shown to indicate the relative suitability of Miscanthus accessions for thermochemical conversion. In this study, the ratio was assessed to examine its use as a selection aid for biochemical conversion. 20 highly-characterised Miscanthus accessions were saccharified using an enzyme mix to determine optimum sugar release. Nine of these accessions spanning high, medium and low H:L ratios were then autoclaved with dilute acid, alkali or water, and enzymically hydrolysed and fermented to produce ethanol. Samples taken throughout the process allowed assessments of released sugars. RESULTS: Enzymic degradation of the biomass showed a relationship between H:L ratio and glucose release, with high glucose release for high H:L ratio accessions and vice versa. Xylose release showed no such relationship. This relationship was maintained following pretreatments and enzyme saccharification, where compound analysis showed that following all pretreatments, accessions with high H:L ratios repeatedly had the highest releases of glucose, xylose and arabinose, and produced more ethanol. Release of all measured compounds increased with the pretreatment severity and ethanol yields from each pretreatment correlated with the respective glucose yield, providing assurance that any inhibitory compounds generated were tolerated by the fermentation yeast. Strong correlations were also seen between glucose release, ethanol and cell wall components, with cellulose showing the highest correlations with ethanol yields for some treatments and H:L ratio with others. CONCLUSIONS: The H:L ratio is a good predictor of ethanol yields and sugar release from Miscanthus in this study but individual components lignin and cellulose also correlate well, especially for hot water and mild acid pretreatments. In conclusion, use of the H:L ratio does not provide any advantages over the concentration of individual cell wall components for predicting sugar release and ethanol yields.

2.
J Anim Sci ; 93(9): 4408-23, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26440341

ABSTRACT

Forage type and management influences the nutritional quality and fatty acid composition of ruminant milk. Replacing grass silage with red clover (RC; L.) silage increases milk fat 18:3-3 concentration. Red clover has a higher polyphenol oxidase (PPO) activity compared with grasses, which has been suggested to decrease lipolysis and . The present study characterized the abundance and fatty acid composition of esterified lipid and NEFA before and after ensiling of grass and RC to investigate the influence of forage species, growth stage, and extent of fermentation on lipolysis. A randomized block design with a 2 × 3 × 4 factorial arrangement of treatments was used. Treatments comprised RC or a mixture of timothy ( L.) and meadow fescue ( Huds.) harvested at 3 growth stages and treated with 4 levels of formic acid (0, 2, 4, and 6 L/t). Lipid in silages treated with 0 or 6 L/t formic acid were extracted and separated into 4 fractions by TLC. Total PPO activity in fresh herbage and the content of soluble bound phenols in all silages were determined. Concentrations of 18:3-3 and total fatty acids (TFA) were higher ( < 0.001) for RC than for grass. For both forage species, 18:3-3 and TFA content decreased linearly ( < 0.001) with advancing growth stage, with the highest abundance at the vegetative stage. Most of lipid in fresh RC and grass herbage (97%) was esterified, whereas NEFA accounted for 71% of TFA in both silages. Ensiling resulted in marginal increases in TFA content and the amounts of individual fatty acids compared with fresh herbages. Herbage total PPO activity was higher ( < 0.001) for RC than grass (11 vs. 0.11 µkatal/g leaf fresh weight). Net lipolysis during ensiling was extensive for both forage species (660 to 759 g/kg fatty acid for grass and 563 to 737 g/kg fatty acid for RC). Formic acid application (0 vs. 6 L/t) resulted in a marked decrease ( = 0.026) in net lipolysis during the ensiling of RC, whereas the opposite was true ( = 0.026) for grass. In conclusion, results suggest that formic acid addition during the ensilage of RC decreases lipolysis . For both plant species, total PPO activity was not associated with the extent of lipolysis . However, bound phenols formed via PPO activity appear to have a role in protecting lipid and protein against degradation in grass and lowering proteolysis of RC during ensiling.


Subject(s)
Fatty Acids/chemistry , Lipids/chemistry , Lipolysis , Poaceae/metabolism , Silage/analysis , Trifolium/metabolism , Animals , Body Weight , Fermentation , Food Analysis , Formates/chemistry
3.
J Dairy Sci ; 92(3): 1136-47, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19233806

ABSTRACT

Polyphenol oxidase (PPO) in conditioned red clover (ensiled or cut and crushed) reduces both proteolysis and lipolysis in the herbage, which has led to increases in N use efficiency and polyunsaturated fatty acid (PUFA) content of milk when offered to dairy cows. In damaged plant cells, PPO is activated and binds protein through the formation of protein-bound phenols. This study investigated a) whether freshly cut red clover could increase N use efficiency and milk PUFA concentrations in dairy cows or whether PPO enzymes require prior activation before feeding to elicit a response, and b) apparent whole-tract amino acid digestibility to help determine the effect of PPO on amino acid utilization. Six multiparous Holstein x Friesian dairy cows in mid-lactation were allocated at random to 1 of 3 dietary treatments in a 3 x 3 Latin square: a control treatment of grass (low PPO, G); red clover (high PPO, RC), and conditioned red clover (high fully activated PPO, CRC). The CRC herbage was cut and chopped in the field and then transported with the G and RC herbages to the animal house. Each period consisted of a 2-wk adaptation to diet and a week of measuring dietary effects (N balance and milk collection). The PPO activity was greatest in the RC treatment as fed, whereas activation of latent PPO enzyme and protein-bound phenol levels were greatest in the CRC diet. Dry matter and total fatty acid intakes were comparable across treatments (18.8 kg/d and 550 g/d, respectively). Milk yields and total fatty acid content were similar across treatments (32.6 kg/d and 34.8 mg/mL, respectively). Cows offered either RC or CRC had greater levels of protein, C18 PUFA and total long-chain PUFA in their milk than animals offered grass with no difference between RC and CRC. Nitrogen intakes, and output in milk, urine, and feces were greater in cows offered the 2 red clover treatments than G, with no difference between RC and CRC. However, there were no differences in N use efficiency among diets as measured by the proportion of feed N converted into milk N, possibly as the result of the excessive supply of N with the red clover diets. Amino acid apparent whole-tract digestibilities were greater when on RC than G diets and intermediate when on CRC for all amino acids, with the exception of Met, which was reduced in cows on both red clover diets compared with G. It is proposed that the PPO trait could show more benefit to ruminants if red clover was fed in combination with lesser N-containing forages or if red clover was bred to contain less N.


Subject(s)
Diet/veterinary , Fatty Acids, Unsaturated/analysis , Lactation/physiology , Milk/chemistry , Nitrogen/metabolism , Trifolium/metabolism , Amino Acids/analysis , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Body Weight/physiology , Catechol Oxidase/metabolism , Cattle , Cross-Over Studies , Dairying , Digestion/physiology , Eating/physiology , Feces/chemistry , Female , Milk/metabolism , Trifolium/chemistry , Trifolium/enzymology
4.
J Appl Microbiol ; 89(3): 442-51, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11021576

ABSTRACT

A study was carried out on the changes occurring in the amino acid fraction of a hybrid ryegrass during ensilage in laboratory-scale silos to help to establish the relative roles of plant and microbial proteases on protein degradation in the silo. Herbage treatments included (i) normal grass without treatment (ii) lambda-irradiated grass (sterile) without treatment (iii) sterile, inoculated with a strain of Lactobacillus plantarum and (iv) sterile, inoculated with a strain of Lactobacillus paracasei subsp. paracasei. These treatments had a significant effect on silage amino acid profiles. Concentrations of free amino acids and the extent of amino acid catabolism varied with treatment. However, levels were notably higher in control silages after 90 days (free amino acid nitrogen constituting 54% of total amino acid nitrogen compared with 37, 32 and 22% for treatments i, ii and iv, respectively). These results indicate that the extent of protein hydrolysis during ensilage is influenced by factors other than rate of pH decline and plant protease activity, and that microbial proteases play a role.


Subject(s)
Animal Feed/microbiology , Lactobacillus/physiology , Silage/microbiology , Amino Acids/analysis , Animal Nutritional Physiological Phenomena , Animals , Fermentation , Gamma Rays , Nitrogen/analysis , Poaceae/microbiology , Secale/microbiology , Sterilization , Time Factors
5.
J Interferon Res ; Spec No: 79-84, 1992 May.
Article in English | MEDLINE | ID: mdl-1379289

ABSTRACT

Skin fibroblast cell cultures, derived from male adult lung cancer patients, an adult control population, and a newborn population were examined for their susceptibility to transformation with Kirsten murine sarcoma virus and their ability to respond to an interferon inducer (poly I.poly C). An association between sensitivity to viral transformation and induction of interferon was observed. Cultures derived from lung cancer patients demonstrated an increased sensitivity to virus transformation and a decreased ability to respond to interferon induction as compared with age-matched controls and newborns.


Subject(s)
Interferons/biosynthesis , Lung Neoplasms/metabolism , Skin/metabolism , Adult , Aged , Cell Line , Cell Transformation, Viral/physiology , Cells, Cultured , Fibroblasts/metabolism , Humans , Interferons/analysis , Kirsten murine sarcoma virus/genetics , Lung Neoplasms/immunology , Male , Middle Aged
6.
Pigment Cell Res ; 4(5-6): 225-33, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1668559

ABSTRACT

Verapamil, a calcium channel antagonist, inhibits murine B16 melanoma and colon adenocarcinoma C26 tumor metastasis by altering platelet aggregation [Tsuruo, T., et al. (1985) Cancer Chemother. Pharmacol., 14:30-33]. However, the role of calcium homeostasis in regulating several biochemical pathways implicated in other steps of the metastatic cascade suggests that calcium channel antagonists could also inhibit metastasis by other mechanisms. In this report, non-toxic doses of verapamil reversibly decreased human A375M and C8161 melanoma cell invasion and metastasis in a dose-dependent manner. Verapamil reduced cellular invasion and metastases by up to 96% (range 78-96%). Concomitantly, verapamil disrupts microtubule and microfilament organization and inhibits unidirectional cell migration but does not affect cellular adhesion to endothelial monolayers or reconstituted basement membranes. In addition, tumor cells treated with verapamil have a decrease in mRNA of type IV collagenase, a proteinase important in tumor cell degradation of basement membranes. Collectively, these data offer additional evidence regarding the mechanisms of action of verapamil as an anti-metastatic agent.


Subject(s)
Neoplasm Invasiveness , Neoplasm Metastasis/prevention & control , Verapamil/therapeutic use , Animals , Cytoskeletal Proteins/drug effects , Female , Humans , Lung Neoplasms/secondary , Matrix Metalloproteinase 9 , Melanoma/secondary , Mice , Mice, Nude , Microbial Collagenase/drug effects , RNA, Messenger/drug effects , RNA, Neoplasm/drug effects , Tumor Cells, Cultured
7.
Appl Environ Microbiol ; 57(9): 2742-9, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1768146

ABSTRACT

The processing of phagosomes containing Legionella pneumophila and Escherichia coli were compared in Tetrahymena vorax, a hymenostome ciliated protozoan that prefers lower temperatures. L. pneumophila did not multiply in the ciliate when incubated at 20 to 22 degrees C, but vacuoles containing L. pneumophila were retained in the cells for a substantially longer time than vacuoles with E. coli. Electron micrographs showed no evidence of degradation of L. pneumophila cells through 12 h, while E. coli cells in the process of being digested were observed in vacuoles 75 min after the addition of the bacterium. T. vorax ingested L. pneumophila normally, but by 10 to 15 min, the vacuolar membrane appeared denser than that surrounding nascent or newly formed phagosomes. In older vacuoles, electron-dense particles lined portions of the membrane. Acidification of the phagosomes indicated by the accumulation of neutral red was similar in T. vorax containing L. pneumophila or E. coli. This ciliate could provide a model for the analysis of virulence-associated intracellular events independent of the replication of L. pneumophila.


Subject(s)
Cold Temperature , Legionella pneumophila/growth & development , Tetrahymena/microbiology , Water Microbiology , Animals , Phagosomes/microbiology , Tetrahymena/ultrastructure , Vacuoles/microbiology
8.
Pigment Cell Res ; 3(3): 162-7, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2127098

ABSTRACT

Three human melanoma cell lines of varying invasive and metastatic potential were analyzed for their ability to express HLA-DR antigens on the cell surface as well as transcriptionally at the mRNA level in the presence and absence of IFN-gamma treatment. Cells of low and intermediate metastatic and invasive potential showed a high percentage of HLA-DR surface expression, both before (91.2-99.9%) and after (97.8-99.9%) IFN-gamma treatment, as quantitated by flow cytometry. In contrast, cells of high metastatic and invasive potential expressed barely detectable levels of HLA-DR-positive cells before IFN-gamma treatment (0.3-0.6%) and displayed elevated levels following treatment (42.3-89.4%). Allowing the highly metastatic cells to recover for 7 or 14 days following IFN-gamma treatment resulted in barely detectable levels of HLA-DR-positive cells. Northern blot analyses of HLA-DR transcription levels showed a strong expression in cells of low and intermediate metastatic and invasive potential. HLA-DR mRNA levels were not detectable in control cells of high metastatic potential nor in those cells which had undergone 7- and 14-day recovery periods following IFN-gamma treatment. There was, however, an induction of HLA-DR expression in the cells that had been treated with IFN-gamma for 72 hr and allowed no recovery period. In addition, a punctate, receptor-like pattern of immunofluorescence staining pattern for cell surface HLA-DR was seen after a 72 hr IFN-gamma treatment in the highly metastatic cells. In contrast, cells of low and intermediate metastatic potential expressed a homogeneous ring-like pattern of antigen expression.


Subject(s)
HLA-DR Antigens/genetics , Interferon-gamma/pharmacology , Melanoma/pathology , Neoplasm Metastasis/pathology , Blotting, Northern , Cell Line , Flow Cytometry , Fluorescent Antibody Technique , Gene Expression/drug effects , HLA-DR Antigens/metabolism , Humans , Melanoma/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism
9.
J Biol Stand ; 14(4): 261-71, 1986 Oct.
Article in English | MEDLINE | ID: mdl-2881930

ABSTRACT

Protective antigen was extracted from Bordetella pertussis cells with 1.0 M NaCl and precipitated with ammonium sulfate, 20-40% saturation (designated fraction 15A-1B). The protective antigen was purified further by detergent (Emulphogene BC720) treatment and adsorption to aluminum hydroxide gel (designated fraction 15A-108A). Compared with B. pertussis vaccine and fraction 15A-1B, fraction 15A-108A retained protective activity as assessed by the mouse protection test, but had reduced protein and markedly reduced endotoxin content. Fraction 15A-108A also had reduced leukocytosis-promoting, histamine sensitizing splenomegaly-inducing, and adjuvant activities. Emulphogene treatment provided a relatively simple method for removing endotoxin from a potential acellular B. pertussis vaccine.


Subject(s)
Detergents/pharmacology , Lipopolysaccharides/isolation & purification , Pertussis Vaccine/analysis , Surface-Active Agents/pharmacology , Adjuvants, Immunologic/physiology , Animals , Antigens, Bacterial/immunology , Antigens, Bacterial/isolation & purification , Bordetella pertussis/drug effects , Bordetella pertussis/immunology , Cell Fractionation , Histamine/administration & dosage , Histamine/immunology , Immunization , Leukocytosis/etiology , Mice , Mice, Inbred Strains , Organ Size , Spleen/pathology
10.
In Vitro Cell Dev Biol ; 22(5): 263-72, 1986 May.
Article in English | MEDLINE | ID: mdl-2872200

ABSTRACT

Recent studies in our laboratory have shown that five established rat hepatoma cell lines provide a wide spectrum of tumor-associated aldehyde dehydrogenase (ALDH) activity representative of the range of activities of this enzyme seen in primary rat hepatocellular carcinomas. Four newly established rat hepatoma cell lines, RLT-2M, RLT-3C, RLT-9F, and RLT-5G, were derived from a primary hepatocellular carcinoma. The primary tumor was induced by a single injection of diethylnitrosamine (15 microM/g body weight) to a 1-d-old female S-D rat followed at weaning by chronic phenobarbital treatment. RLT-2M was established from outgrowths of minced tumor pieces. RLT-3C, RLT-9F, and RLT-5G were cloned from RLT-2M by the serial endpoint dilution. All four lines have been maintained in culture for over 100 passages. The ALDH phenotype in both the primary tumor and the four new cell lines was determined by total activity assay, gel electrophoresis, and histochemistry. By total activity assay, the primary tumor did not possess significant tumor-ALDH activity. In contrast, the four new cell lines expressed tumor-ALDH activity. However, they differed in their basal ALDH activities and in ALDH inducibility by 3-methylcholanthrene, benzo(a)pyrene, and phenobarbital. Additionally, significant decreases in tumor-ALDH activity occurred when cells from each line were passaged in vivo. The four lines have been characterized by light and electron microscopic morphology, tumorigenicity, chromosome number, doubling time, and colony formation efficiency in soft agar.


Subject(s)
Aldehyde Dehydrogenase/metabolism , Liver Neoplasms, Experimental/enzymology , Aldehyde Dehydrogenase/analysis , Aldehyde Dehydrogenase/biosynthesis , Animals , Benzo(a)pyrene/pharmacology , Cell Division , Cell Line , Diethylnitrosamine , Enzyme Induction , Female , Isoenzymes/analysis , Karyotyping , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms, Experimental/pathology , Methylcholanthrene/pharmacology , NADP/pharmacology , Neoplasm Transplantation , Organoids/ultrastructure , Phenobarbital , Phenotype , Rats , Tyrosine Transaminase/metabolism
11.
J Immunopharmacol ; 8(4): 589-609, 1986.
Article in English | MEDLINE | ID: mdl-3027186

ABSTRACT

Peritoneal exudate cells collected from mice 7 days after treatment with Bordetella pertussis vaccine exhibited significant in vitro antiviral activity against vesicular stomatitis virus (VSV). Vaccine-induced peritoneal exudate cells exhibited both intrinsic and extrinsic antiviral activity in culture with target VSV-infected L cells. Virus replication was poor in the vaccine-induced exudate cells. Coculture of vaccine-induced exudate cells and VSV-infected L cell targets decreased virus yield. The activity appeared specific for infected cells and at least a portion of the antiviral activity was directed against the initial infection cycle. Nonadherent vaccine-induced exudate cells showed an increase in antiviral activity over total vaccine-induced exudate cells.


Subject(s)
Peritoneal Cavity/immunology , Pertussis Vaccine/pharmacology , Virus Replication , Animals , Killer Cells, Natural/immunology , L Cells/microbiology , Mice , Mice, Inbred C3H , Peritoneal Cavity/cytology , Vesicular stomatitis Indiana virus/growth & development
12.
Biochim Biophys Acta ; 843(3): 180-5, 1985 Dec 13.
Article in English | MEDLINE | ID: mdl-3933572

ABSTRACT

We have proposed developing rat hepatoma cell lines as an in vitro model for studying the regulation of changes in aldehyde dehydrogenase activity occurring during hepatocarcinogenesis. Aldehyde dehydrogenase purified in a single step from HTC rat hepatoma cells is identical to the aldehyde dehydrogenase isolated from rat hepatocellular carcinomas. HTC aldehyde dehydrogenase is a 100 kDa dimer composed of 54-kDa subunits, prefers NADP+ as coenzyme, and preferentially oxidizes benzaldehyde-like aromatic aldehydes but not phenylacetaldehyde. The substrate and coenzyme specificity, effects of disulfiram, pH profile and isoelectric point of HTC aldehyde dehydrogenase are also identical to these same properties of the tumor aldehyde dehydrogenase. In immunodiffusion, both isozymes are recognized with complete identity by anti-HTC aldehyde dehydrogenase antibodies. Having established that HTC aldehyde dehydrogenase is very similar, if not identical, to the aldehyde dehydrogenase found in hepatocellular carcinomas, simplifies the development of molecular probes for examination of the regulation of tumor aldehyde dehydrogenase activity in vivo and in vitro.


Subject(s)
Aldehyde Dehydrogenase/isolation & purification , Liver Neoplasms, Experimental/enzymology , Aldehyde Dehydrogenase/metabolism , Animals , Cell Line , Immunodiffusion , Kinetics , Molecular Weight , NAD/metabolism , NADP/metabolism , Oxidation-Reduction , Rats
13.
Infect Immun ; 47(3): 587-91, 1985 Mar.
Article in English | MEDLINE | ID: mdl-2982736

ABSTRACT

Treatment of mice with Bordetella pertussis vaccine rendered mice resistant to mouse adenovirus infection. The resistant state took at least 5 days to develop, and susceptibility returned to a portion of the test population 35 days after treatment. Transient resistance developed in congenitally athymic mice also. Treatment with a dose of 25 micrograms (dry weight) of B. pertussis vaccine protected approximately 50% of the test population. Vaccines prepared from several different strains of B. pertussis were capable of inducing resistance, and the induction of resistance was not dependent on the mouse strain used for testing. Cross-reacting antibodies capable of neutralizing the virus or protecting against a challenging infection were not induced by treatment with B. pertussis vaccine.


Subject(s)
Adenoviridae Infections/prevention & control , Pertussis Vaccine/immunology , Animals , Dose-Response Relationship, Immunologic , Hot Temperature , Leukocytes/immunology , Macrophages/immunology , Mice , Mice, Nude/immunology , Spleen/immunology , Time Factors , Vaccination
14.
Dev Biol Stand ; 61: 233-40, 1985.
Article in English | MEDLINE | ID: mdl-2872109

ABSTRACT

Treatment of mice by intraperitoneal inoculation of pertussis vaccine or lipopolysaccharide extracted from B. pertussis will effect resistance to rabies virus, encephalomyocarditis virus, Semliki Forest virus, and Herpes simplex virus. Our previous observations indicated that treatment of C3H/HeN (+/nu) and BDF1 mice with pertussis vaccine injected i.p. five days prior to a mouse adenovirus lethal dose i.p. challenge elicited resistance to clinical disease and death. Susceptibility returned to a portion of the test population 35 days after pertussis vaccine treatment. The pertussis vaccine induced resistance developed in athymic (nude) mice also; however, the population succumbed to infection 35 days later. Titration of pertussis vaccine with respect to induction of resistance indicated the median effective dose (ED50) was approximately 25 micrograms dry weight. This report describes the antiviral activity of acellular components extracted from pertussis vaccine. Extraction of B. pertussis cells with 1.0M NaCl and ammonium sulfate fractionation (20-40% saturation) of the extract resulted in an acellular preparation that induced resistance to lethal dose mouse adenovirus infection. The resistance inducing activity was retained after treatment of the extract with detergent (GAF Emulphogene BC 720) to remove lipopolysaccharide and adsorption to alum gel. Comparison of endotoxin content of pertussis vaccine acellular fractions, polysaccharide fraction and purified lipopolysaccharide suggested that endotoxin probably plays a role in the induction of resistance. The endotoxin content of a Emulphogene-treated preparation that protected 80% of a test population was 39 ng. The lipopolysaccharide extracted from Escherichia coli, Vibrio cholerae, Salmonella typhimurium, and Salmonella minnesota did not induce a resistant state seven days after administration; however, lipopolysaccharide extracted from B. pertussis induced a resistant state.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Adenoviridae Infections/prevention & control , Adjuvants, Immunologic , Antiviral Agents , Bordetella pertussis/immunology , Animals , Antiviral Agents/isolation & purification , Bacterial Proteins/immunology , Bacterial Proteins/isolation & purification , Female , Lipopolysaccharides/immunology , Male , Mice , Mice, Inbred C3H , Pertussis Vaccine/immunology , Virulence Factors, Bordetella/immunology
15.
J Interferon Res ; 5(3): 465-70, 1985.
Article in English | MEDLINE | ID: mdl-4056491

ABSTRACT

Skin fibroblast cell cultures, derived from male adult lung cancer patients, an adult control population, and a newborn population were examined for their susceptibility to transformation with Kirsten murine sarcoma virus and their ability to respond to an interferon inducer (poly I X poly C). An association between sensitivity to viral transformation and induction of interferon was observed. Cultures derived from lung cancer patients demonstrated an increased sensitivity to virus transformation and a decreased ability to respond to interferon induction as compared with age-matched controls and newborns.


Subject(s)
Interferon Type I/biosynthesis , Lung Neoplasms/immunology , Skin/immunology , Adult , Animals , Cell Line , Cells, Cultured , Fibroblasts/drug effects , Fibroblasts/immunology , Humans , Kidney , Kirsten murine sarcoma virus/immunology , Male , Poly I-C/pharmacology , Rats , Skin/drug effects
16.
Cancer Res ; 44(11): 5219-26, 1984 Nov.
Article in English | MEDLINE | ID: mdl-6488182

ABSTRACT

Significant changes in aldehyde dehydrogenase (ALDH) activity occur during rat hepatocarcinogenesis in vivo. An NADP-dependent tumor ALDH isozyme has been studied extensively. To better understand the nature, origin, and importance of this tumor-associated phenotypic change, we have examined the ALDH activity of five well-established rat hepatoma cell lines, H4-II-EC3, HTC, McA-RH7777, JM1, and JM2. HTC, JM1, and JM2 express the tumor ALDH phenotype, as indicated by elevated NADP-dependent, benzaldehyde-oxidizing activity, the appearance of new isozymes by electrophoresis, and characteristic histochemical localization of ALDH activity in situ. The tumor ALDH phenotype is not detected in McA-RH7777 cells. H4-II-EC3 has intermediate tumor ALDH activity. Thus, the 5 cell lines provide a spectrum of tumor ALDH activities representative of the range of activities seen in vivo. Benzo(a)pyrene, 3-methylcholanthrene, and phenobarbital induce hepatic ALDH activity after treatment in vivo. The ability of these compounds to induce ALDH in vitro was assessed in H4-II-EC3, McA-RH7777, HTC, JM1, and JM2. Treatment of cell cultures for 72 hr with 3-methylcholanthrene (1.0 mM) increases the NADP-dependent ALDH activity in H4-II-EC3 and McA-RH7777 cell lines up to 34- and 11-fold, respectively. Treatment with benzo(a)pyrene (1.0 mM) also increases the NADP-dependent ALDH activity in both lines up to 17- and 48-fold, respectively. Treatment with 3-methylcholanthrene or benzo(a)pyrene increases ALDH activity 2-fold in HTC and JM2 but does not increase NADP-dependent ALDH activity in JM1. Only marginal increases in NADP-dependent ALDH are observed after phenobarbital treatment in 4 of 5 cell lines. The induction of ALDH is blocked by actinomycin D, alpha-amanitin, and cycloheximide. These studies support our hypothesis that changes in ALDH activity observed in vivo are due to mutational events occurring in initiated cells. It appears that rat hepatoma cell lines will provide an in vitro model for studying genetic regulation of the tumor ALDH.


Subject(s)
Aldehyde Dehydrogenase/metabolism , Liver Neoplasms, Experimental/enzymology , Aldehyde Dehydrogenase/biosynthesis , Amanitins/pharmacology , Animals , Benzo(a)pyrene/pharmacology , Cell Line , Cycloheximide/pharmacology , Dactinomycin/pharmacology , Enzyme Induction , Kinetics , Methylcholanthrene/pharmacology , Phenotype , Rats
18.
Immunopharmacology ; 3(2): 101-6, 1981 Jun.
Article in English | MEDLINE | ID: mdl-6972935

ABSTRACT

Administration of Bordetella pertussis (B. pertussis), Corynebacterium parvum (C. parvum), and several other immunoactive substances is known to cause a marked decrease in the activity of the hepatic microsomal mixed-function oxidase system. The effect of C parvum has been reported to involve the reticuloendothelial system. In the present study, the effect of B. pertussis administration to decrease hepatic microsomal drug metabolism was studied in unoperated, sham-operated, and splenectomized mice as well as in athymic nude (nu/nu) mice and their phenotypically heterozygous (+/nu) littermates. Administration of B. pertussis to the splenectomized, sham-operated, and unoperated mice resulted in a decrease in the activity of the microsomal enzyme system that was approximately the same for each of the three groups of animals. Administration of B. pertussis to nu/nu mice and the +/nu mice also decreased the microsomal enzyme activity measured 24 hr after injection. However, at 7 days after B. pertussis administration, the hepatic drug-metabolizing activity of the nu/nu mice was not significantly different from control values, whereas the activity of the +/nu mice was still significantly depressed. The failure of splenectomy to prevent the decrease in microsomal mixed-function oxidase activity caused by B. pertussis indicated that the effect of this agent differs from that of C. parvum, whose effect was prevented by splenectomy. Indeed, the results obtained with the athymic nude mouse suggests that the depression of hepatic mixed-function oxidase activity by B. pertussis may involve T-cell dependent responses.


Subject(s)
Liver/enzymology , Mixed Function Oxygenases/metabolism , Oxidoreductases/metabolism , Pertussis Vaccine/immunology , Adjuvants, Immunologic/pharmacology , Animals , Bacterial Vaccines/immunology , Female , Mice , Mice, Nude , Spleen/immunology , Splenectomy , T-Lymphocytes/immunology , Thymus Gland/immunology
20.
Intervirology ; 14(5-6): 321-5, 1980.
Article in English | MEDLINE | ID: mdl-6265402

ABSTRACT

Prophylactic treatment of hamsters and chickens with an aromatic retinoid (Ro 10-9359) inhibited Rous sarcoma virus (RSV) tumorigenesis. Retinoid administration to chickens with RSV-induced tumors resulted in tumor regression and/or confinement to the primary site. The retinoid also exerted a therapeutic effect on Shope virus papilloma development in the skin of rabbits.


Subject(s)
Etretinate/therapeutic use , Sarcoma, Avian/prevention & control , Tretinoin/analogs & derivatives , Tumor Virus Infections/drug therapy , Animals , Antibodies, Viral/biosynthesis , Avian Leukosis Virus/immunology , Avian Sarcoma Viruses/growth & development , Chickens , Cricetinae , Mesocricetus , Mice , Sarcoma, Avian/drug therapy
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