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1.
Space Sci Rev ; 220(4): 37, 2024.
Article in English | MEDLINE | ID: mdl-38756703

ABSTRACT

The Lunar Environment heliospheric X-ray Imager (LEXI) is a wide field-of-view soft X-ray telescope developed to study solar wind-magnetosphere coupling. LEXI is part of the Blue Ghost 1 mission comprised of 10 payloads to be deployed on the lunar surface. LEXI monitors the dayside magnetopause position and shape as a function of time by observing soft X-rays (0.1-2 keV) emitted from solar wind charge-exchange between exospheric neutrals and high charge-state solar wind plasma in the dayside magnetosheath. Measurements of the shape and position of the magnetopause are used to test temporal models of meso- and macro-scale magnetic reconnection. To image the boundary, LEXI employs lobster-eye optics to focus X-rays to a microchannel plate detector with a 9.1×∘9.1∘ field of view.

5.
Virology ; 193(2): 1006-9, 1993 Apr.
Article in English | MEDLINE | ID: mdl-8460472

ABSTRACT

A full-length cDNA clone (pMCM41) was constructed to contain the exact 5' end of MCMV behind a T7 RNA polymerase promoter and a Smal site at the 3' end. Uncapped RNA synthesized from pMCM41 has the exact 3' end of viral RNA (vRNA) but is missing the cap found on vRNA. This RNA was infectious in protoplasts from black Mexican sweet (BMS) maize (Zea mays) suspension cultures. Uncapped transcripts were also infectious when inoculated onto maize plants and produced an infection indistinguishable from vRNA-inoculated plants. Capped pMCM41 transcripts which initiated at position +2 of the cDNA clone, as well as capped or uncapped RNA synthesized from a clone containing an extra G between the T7 promoter and the 5' end of MCMV sequence (pMCM721), were less infectious than uncapped pMCM41 transcripts in BMS protoplasts. The transcripts one nucleotide longer or shorter than uncapped pMCM41 transcripts were not able to infect maize plants.


Subject(s)
DNA, Viral/genetics , Plant Viruses/genetics , RNA, Viral/genetics , Transcription, Genetic , Zea mays/microbiology , Base Sequence , Blotting, Northern , Capsid/biosynthesis , Capsid/genetics , Cloning, Molecular , Kinetics , Molecular Sequence Data , Oligodeoxyribonucleotides , Plasmids , Polymerase Chain Reaction , Protoplasts/microbiology
7.
Virology ; 181(1): 382-5, 1991 Mar.
Article in English | MEDLINE | ID: mdl-1994587

ABSTRACT

Maize chlorotic mottle virus (MCMV) is a 30-nm icosahedral plant virus composed of a single 25-kDa capsid protein component and a 4.4-kb single-stranded, positive-sense genomic RNA. Northern blot hybridization analysis detected a single 3'-terminal 1.1-kb subgenomic RNA in infected plants. Virion RNA directs the synthesis of several polypeptides in a rabbit reticulocyte lysate in vitro translation system of which only the 25-kDa polypeptide is immunoprecipitated by MCMV capsid protein antiserum. The 1.1-kb subgenomic RNA is a highly efficient messenger RNA for capsid protein synthesis. Positive polarity in vitro transcripts from 3'-proximal MCMV cDNA clones direct the synthesis of the capsid protein in in vitro translation experiments. These data suggest that the MCMV capsid protein is expressed from a subgenomic RNA in vivo, and that the 25-kDa capsid protein is encoded by the 3'-proximal open reading frame in the MCMV genome.


Subject(s)
Capsid/genetics , Genes, Viral , Plant Viruses/genetics , RNA, Messenger/genetics , Viral Structural Proteins/genetics , Base Sequence , Molecular Sequence Data , Oligonucleotide Probes , Open Reading Frames , Plasmids , RNA, Viral/genetics , RNA, Viral/isolation & purification , Sequence Homology, Nucleic Acid , Zea mays
8.
Nutr Cancer ; 13(3): 141-52, 1990.
Article in English | MEDLINE | ID: mdl-2308871

ABSTRACT

Although in three different mouse tumor systems with corn oil as dietary fat we previously found that milk protein decreased tumor development compared with beef, the results were reversed in 1,2-dimethylhydrazine (DMH)-injected mice. The purpose of this study was to determine if the latter result was due to the protein source. BALB/c mice (n = 280) were divided into five diet groups and injected 10 times at weekly intervals with DMH (20 mg/kg wt) or saline. Four diets contained 11% protein (casein, milk, or beef) and 5% fat (corn oil or beef tallow), and the AIN-76A diet was used as a control diet. The source of fat was a significant modulator of tumor development. Corn oil markedly increased total tumor volume and the number of tumors per mouse compared with beef tallow. Its tumor-enhancing effects were evident when it was combined with milk but not with casein. In addition, significantly lower lymphoproliferation and T-cell cytotoxicity against colon tumor cell targets was associated with corn oil consumption, whereas nonfat milk as the protein source was related to normal oxidative burst capacity of phagocytes. These results demonstrate that the source of dietary fat, in addition to the protein source, has a profound effect on both tumor development and immune responsiveness in this animal tumor system.


Subject(s)
Colorectal Neoplasms/etiology , Dietary Fats/pharmacology , Dietary Proteins/pharmacology , 1,2-Dimethylhydrazine , Animals , Carcinogens , Colorectal Neoplasms/chemically induced , Colorectal Neoplasms/immunology , Dimethylhydrazines , Luminescent Measurements , Lymphocyte Activation/immunology , Macrophages/immunology , Male , Mice , Mice, Inbred BALB C , T-Lymphocytes, Cytotoxic/immunology
9.
Soc Sci Med ; 30(1): 83-94, 1990.
Article in English | MEDLINE | ID: mdl-2106168

ABSTRACT

Much geographical work about mental illness has been aggregative in nature and, consequently, has ignored variation that might be attributed to individuals. The research reported here is intended to reverse this trend by applying the methods of categorical data analysis to the detailed patient histories contained in the Salford Psychiatric Case Register. The paper begins by reviewing the changing prevalence rates for various diagnoses and types of care in Salford between 1968 and 1986. In the light of this background log-linear data models are fitted to evaluate relationships between service usage and patient age, diagnosis and marital status and residential location at two survey points within the study period. Significant relationships are examined in terms of their temporal stability (such as the diagnosis of schizophrenia and a marital status of single) and instability (the changing role of the community psychiatric nurse) to isolate the main combinations of categories to influence the uptake of psychiatric services.


Subject(s)
Mental Disorders/epidemiology , Models, Statistical , Adolescent , Adult , Age Factors , Aged , Algorithms , Dementia/epidemiology , Humans , Long-Term Care , Marriage , Mental Disorders/diagnosis , Mental Disorders/therapy , Middle Aged , Neurotic Disorders/epidemiology , Registries , Residence Characteristics , Schizophrenia/diagnosis , Schizophrenia/epidemiology , Time Factors , United Kingdom
10.
Nucleic Acids Res ; 17(8): 3163-77, 1989 Apr 25.
Article in English | MEDLINE | ID: mdl-2726455

ABSTRACT

The complete nucleotide sequence of the maize chlorotic mottle virus (MCMV) genome has been determined to be 4437 nucleotides. The viral genome has four long open reading frames (ORFs) which could encode polypeptides of 31.6, 50, 8.9 and 25.1 kd. If the termination codons, for the polypeptides encoded by the 50 and 8.9 kd ORFs are suppressed, readthrough products of 111 and 32.7 kd result. The 31.6 and 50 kd ORFs overlap for nearly the entire length of the 31.6 kd ORF. Striking amino acid homology has been observed between two potential polypeptides encoded by MCMV and polypeptides encoded by carnation mottle virus (CarMV) and turnip crinkle virus (TCV). The 25.1 kd ORF most likely encodes the capsid protein. The similar genome organization and amino acid sequence homology of MCMV with CarMV and TCV suggest an evolutionary relationship with these members of the carmovirus group.


Subject(s)
Plant Viruses/genetics , Zea mays/microbiology , Amino Acid Sequence , Base Sequence , Cloning, Molecular , Genes, Viral , Molecular Sequence Data , RNA, Viral/genetics , Restriction Mapping , Viral Proteins/genetics
12.
Plant Physiol ; 84(4): 1185-92, 1987 Aug.
Article in English | MEDLINE | ID: mdl-16665582

ABSTRACT

A 230 base pair DNA segment containing the sequences 5' to the 700 to 750 nucleotide (nt) transcript 7' (ORF 3; RF Barker, KB Idler, DV Thompson, JD Kemp 1983 Plant Mol Biol 2: 335-350) of the octopine tumor inducing plasmid pTiA6 has been isolated. This region has (a) 180 base pairs of DNA upstream of the TATA box, (b) the start of RNA synthesis, and (c) the entire 5' untranslated region of the gene. We have fused this presumed promoter fragment to the neomycin phosphotransferase II (NPTII) gene from Tn5 in a plant expression cassette. After recombination into a tumor inducing plasmid delivery plasmid, this cassette confers selectable kanamycin resistance to transformed sunflower cells. Removal of the out-of-frame ATG in the 5' leader sequence of the NPTII gene by two different modifications increased both the levels of NPTII enzyme activity and the ID(50) for kanamycin in the tumor cells. The promoter region of the transcript 7 gene gives levels of kanamycin resistance equivalent to the nopaline synthase promoter and octopine synthase promoter when used in the same constructions and assayed in the same tissues.

13.
Int J Hyperthermia ; 3(4): 361-4, 1987.
Article in English | MEDLINE | ID: mdl-3668317

ABSTRACT

A comparison was made of three study arms delivering localized fractionated hyperthermia followed by irradiation for two weeks. The treatment results demonstrated 18-week survival and NED survival to be 35 per cent (7/20) and 30 per cent (6/20) respectively for heat and irradiation 5 days per week, 57.9 per cent (11/19) and 52.6 per cent (10/19) for combined treatment 3 days per week and 27.8 per cent (5/18) for heat 3 days per week and irradiation 5 days per week. It is felt that thermotolerance will account for the lack of difference between 24 h and 48 h irradiation schedules when irradiation is given daily. Irradiation fraction size, however, is suggested as a moderating variable as well.


Subject(s)
Hyperthermia, Induced/methods , Neoplasms, Experimental/therapy , Animals , Combined Modality Therapy , Mice , Mice, Inbred BALB C , Neoplasms, Experimental/mortality , Neoplasms, Experimental/radiotherapy , Time Factors
14.
J Natl Cancer Inst ; 78(5): 951-9, 1987 May.
Article in English | MEDLINE | ID: mdl-3472003

ABSTRACT

Effects of dietary vitamin B6 at levels ranging from deficiency to megadoses on the development of herpes simplex virus type 2-transformed (H238) cell-induced tumors and on in vitro responses relating to cell-mediated immunity were examined. Male BALB/cByJ mice (n = 260), 5 weeks of age, were fed 20% casein diets containing pyridoxine (PN) at 0.2, 1.2 for the control diet, 7.7, or 74.3 mg/kg diet for 4-11 weeks. After 4 weeks of dietary treatment, 120 of the mice received an injection of H238 cells; mice without H238 injection served as controls. At 4, 8, and 11 weeks, animals from each group were euthanized and blood and spleen samples obtained. Mice fed 0.2 mg PN developed mild deficiency symptoms and gained significantly less weight than those fed 1.2-, 7.7-, and 74.3-mg PN diets. Thirteen to 16 days after tumor cell injection, primary tumor incidence was lowest in mice fed 74.3 mg PN; later, incidence among groups was similar. Mice fed 1.2 mg PN had the largest primary tumor volume, the highest incidence of lung metastases, and the greatest number of metastatic nodules per animal at 7 weeks post injection. Overall, lower tumor volumes were found in animals fed 7.7 and 74.3 mg PN (14 and 32% less than the tumor volume for those fed 1.2 mg PN, respectively); mice fed 0.2 mg PN had the lowest tumor volume. Blood and spleen lymphoproliferative response to stimulation by phytohemagglutinin or concanavalin A generally tended to be higher in mice fed 7.7 and 74.3 mg PN as compared to that in animals fed either 0.2 or 1.2 mg PN. However, decreased mitogen-stimulated responsiveness was observed in all animals with progressive tumor growth. Tumor growth also resulted in splenomegaly and increased thymic atrophy. Significant negative relationships between tumor volume and tumor pyridoxal 5-phosphate (PLP) concentrations were observed for 1.2-, 7.7-, and 74.3-mg PN diet groups. These data suggest that high dietary intake of vitamin B6 may have suppressed tumor development by either immune enhancement or PLP growth regulation of this tumor.


Subject(s)
Neoplasms, Experimental/drug therapy , Pyridoxine/administration & dosage , Animals , Body Weight , Eating , Liver/analysis , Lymphocyte Activation/drug effects , Male , Mice , Mice, Inbred BALB C , Mitogens/pharmacology , Neoplasm Metastasis , Neoplasms, Experimental/immunology , Neoplasms, Experimental/pathology , Organ Size , Pyridoxal Phosphate/analysis , Regression Analysis , Spleen/pathology , Thymus Gland/pathology , Vitamin B 6 Deficiency/complications
16.
Int J Radiat Oncol Biol Phys ; 11(3): 567-74, 1985 Mar.
Article in English | MEDLINE | ID: mdl-3972666

ABSTRACT

Since hypoxic cells rely heavily on glucose metabolism for energy, 2-deoxy-D-glucose (2-DG), an inhibitor of anaerobic glycolysis, would be expected to increase tumor cell killing by heat and thus enhance the effect of concurrent radiation. In order to test this hypothesis two types of BALB/c mouse tumors, one induced by subcutaneous injection of 10(6) herpes virus Type 2-transformed (H238) cells and the other by injection of 1.6 X 10(5) 1,2-dimethylhydrazine-transformed (#51) cells in the right thigh, were subjected to radiation, 2-DG, and heat used singly and in various combinations. Control mice were injected with saline. Three to four weeks after inoculation the mice were assigned to one of eight treatment groups (28 mice/group) so that average tumor volume/group before treatment would be equivalent. A single 2000 rad dose of radiation 3 hr prior to heat and 2-DG injected intraperitoneally at 1 g/kg 30 min before heating were given to some of the groups. Localized heat at 43.5 +/- 0.1 degrees C for 30 min, when used, was administered by means of a water bath. Rectal temperatures were kept below 39 degrees C, whereas intratumor temperatures reached a maximum of 42 degrees C. After treatment, tumor volume, mouse weight, and mortality were noted twice a week for four weeks. In both tumor models, mice receiving radiation plus heat, and radiation plus heat plus 2-DG, had significantly smaller tumors over the entire 4 to 28 day range after treatment than saline-injected control mice. In addition, in the H238 tumor model, addition of 2-DG to treatment with radiation and heat resulted in significantly smaller tumors at 25 days. 2-DG alone or in combination with heat (without radiation) resulted in significantly smaller H238 cell-induced tumors at day 28 post-treatment when compared to the saline controls. The H238 tumor-bearing mice experienced a significant (4.7%) loss in total body weight after heating. It could be that heating trauma produced dehydration and possibly also decreased caloric intake to an extent which could be measured in weight loss. This observation, however, was not made in the heated mice in the #51 tumor model.


Subject(s)
Deoxy Sugars/therapeutic use , Deoxyglucose/therapeutic use , Hyperthermia, Induced , Neoplasms, Experimental/therapy , Animals , Combined Modality Therapy , Male , Mice , Mice, Inbred BALB C , Neoplasm Transplantation , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/radiotherapy
17.
Cancer Immunol Immunother ; 20(2): 97-102, 1985.
Article in English | MEDLINE | ID: mdl-3849982

ABSTRACT

Cell-mediated immunity was investigated in two BALB/c mouse tumor systems using the lymphoblastogenesis test with phytohemagglutinin as the mitogen. This lymphoproliferative response was quantitated using the Stimulation Index (SI). There was little evidence for suppressor cell activity in cell mixing experiments in which spleen cells from #51 cell-injected mice were mixed with spleen cells from normal mice. Following macrophage removal by Sephadex G-10 columns and carbonyl iron ingestion, there were no significant changes in the SI values for spleen cells from the #51 cell-injected mice. In contrast, spleen cells from mice injected with H238 cells, a herpes virus-transformed cell line, had a significantly lower SI value than that of normal mice. Suppressor cell activity was demonstrated in cell mixing experiments in which spleen cells from H238 cell-injected mice were mixed with normal spleen cells. Removal of adherent cells from spleen cells from H238 cell-injected mice by Sephadex G-10 columns restored the SI value to that of normal mice. An increased SI value was also seen after removal of phagocytic cells by carbonyl iron. These results suggested that cells with the functional properties of macrophages played an important part in the immunosuppression observed in the H238 tumor system. Comparison of the two macrophage depletion methods suggested that another cell population was also involved in the suppressive effect. Results of immunofluorescent techniques with anti-Lyt-1 and anti-Lyt-2 monoclonal antibodies show these cells to be Ly 1-, Ly 2,3+ phenotypes of T-lymphocytes.


Subject(s)
Lymphocyte Activation , Macrophages/physiology , Neoplasms, Experimental/immunology , Spleen/immunology , Animals , Cell Adhesion , Chromatography, Gel , Dose-Response Relationship, Drug , Mice , Mice, Inbred BALB C , Phytohemagglutinins/pharmacology
18.
Oncology ; 42(6): 391-8, 1985.
Article in English | MEDLINE | ID: mdl-4069554

ABSTRACT

Radiation (XRT), hyperthermia, 2-deoxy-D-glucose (2DG), and Corynebacterium parvum were given in various combinations to BALB/c mice injected with herpes virus type 2-transformed (H238) cells. Addition of heat significantly increased the antitumor effects of XRT, and the combination of XRT + 2DG + heat resulted in the highest incidence of complete tumor regression. Enhanced activity of phytohemagglutinin-responsive T lymphocytes and natural killer cells capable of killing YAC-1 tumor cells was noted in some of the treatment groups while tumor volume was similar for all of the groups. This enhancement was most likely to be achieved when heat was included as part of the treatment protocol.


Subject(s)
Bacterial Vaccines/therapeutic use , Deoxy Sugars/therapeutic use , Deoxyglucose/therapeutic use , Hot Temperature/therapeutic use , Neoplasms/immunology , Propionibacterium acnes/immunology , Animals , Body Temperature , Body Weight , Cell Line , Combined Modality Therapy , Killer Cells, Natural/immunology , Lymphocyte Activation , Male , Mice , Mice, Inbred BALB C , Neoplasms/pathology , Neoplasms/radiotherapy , Neoplasms/therapy , Organ Size , Phytohemagglutinins/pharmacology , Spleen/drug effects , Spleen/immunology , Time Factors
19.
J Natl Cancer Inst ; 71(4): 867-74, 1983 Oct.
Article in English | MEDLINE | ID: mdl-6578376

ABSTRACT

The development of 1,2-dimethylhydrazine (DMH)-induced colon tumors and immune responses were investigated in male BALB/c mice fed six different equicaloric diets. Milk or beef at a low (11%) or high (33%) level supplied the dietary protein, and corn oil (primarily) at a low (5%) or high (30%) level supplied the fat. Eleven weekly injections of DMH (at 20 mg/kg mouse) or saline were administered. At 59 weeks of age, the milk-fed mice had a significantly higher (P less than or equal to .05) colon tumor incidence than the beef-fed mice, 67 and 16%, respectively. Tumor volume and colon weight in the milk-fed mice were also significantly greater. Low natural killer cell activity against [125I]5-iodo-2'-deoxyuridine-labeled colon tumor cells and high serum blocking of antitumor cell activity were observed in the milk-fed-mice. These mice also exhibited higher T-lymphocyte cytotoxicity against colon tumor cells. These results differ from those of our previous studies and those of numerous epidemiologic investigations.


Subject(s)
Colonic Neoplasms/chemically induced , Dimethylhydrazines/toxicity , Meat , Methylhydrazines/toxicity , Milk Proteins/pharmacology , 1,2-Dimethylhydrazine , Animals , Body Weight , Cattle , Cocarcinogenesis , Colonic Neoplasms/immunology , Colonic Neoplasms/pathology , Cytotoxicity, Immunologic , Diet , Killer Cells, Natural/immunology , Male , Mice , Mice, Inbred BALB C , Organ Size
20.
Cancer Lett ; 19(2): 133-46, 1983 Jun.
Article in English | MEDLINE | ID: mdl-6883304

ABSTRACT

The effects of different sources of dietary protein (milk, soy, wheat, fish and beef), fat (corn oil and butter), and carbohydrate (dextrin and sucrose) on the development of spontaneous mammary tumors in virgin female C3H/HeJ mice were investigated. Weanling mice were randomly divided (28 mice/group) and fed ad libitum one of 14 equicaloric diets containing either 11% or 33% protein and 5% or 30% fat or a standard mouse feed for approximately 2 years. Beginning at 6 months of age, tumor incidence, non-specific deaths, individual weights and amount of food consumed were monitored. Variations in tumor incidence were most pronounced when the mice fed different sources of protein (at a high level) were compared. The mice fed the low fat diets containing either low milk protein (high carbohydrate) or high fish protein generally exhibited the lowest tumor incidence and highest percent survival. High weight gain was correlated with early tumor appearance, but not with tumor incidence later in the experiment. The mice fed a low fat diet containing low milk protein were tumor-free significantly longer than mice fed the diets containing fish or beef. The only groups with 100% tumor incidence by 120 weeks of age were those fed diets containing sucrose (table sugar) or a high fat level.


Subject(s)
Dietary Carbohydrates/administration & dosage , Dietary Fats/administration & dosage , Dietary Proteins/administration & dosage , Mammary Neoplasms, Experimental/epidemiology , Aging , Animals , Butter/adverse effects , Corn Oil , Female , Mammary Neoplasms, Experimental/mortality , Mice , Mice, Inbred C3H , Oils/administration & dosage , Sucrose/administration & dosage
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