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Biomedical subjects

G Wood

Publications and source records attributed to G Wood.

104 records · Page 6Linked to original sources
PubMed1975

The cell-free translation of Rauscher leukemia virus RNA into high molecular weight polypeptides.

Rauscher leukemia virus (RLV) 65-S RNA, 35-S mengovirus RNA and reticulocyte A-rich RNA each stimulated cell-free protein synthesis in a JLS-V5 cell derived S-30 system. rRNA, however, was not stimulatory in this system. Of the stimulated protein products only those synthesized in response to added RLV RNA were immune-precipitable with anti-RLV rabbit serum. Furthermore, cell-free incubations with pactamycin at a concentration which specifically inhibits initiation and not elongation prevented the stimulation of amino acid incorporation in response to added RLV RNA. Analysis of the polypeptides synthesized by the cell-free system in response to reticulocyte A-rich RNA, showed them to be globin-like and, therefore, also mRNA specific. The RLV RNA-directed product included at least two classes of polypeptides (mol. wts of 140 000-185 000 and 50 000-75 000) both of which were larger than the group specific polypeptides of mature virions. None of the internal structural polypeptides of mature virions were synthesized in response to RLV RNA. The large molecular weight, viral-specific polypeptides are candidate precursor polyproteins which may represent the translational products of a polycistronic mRNA with a single initiation site.

Amino Acids↗
PubMed1971

Cross-neutralization of leptospiral hemolysins from different serotypes.

Cross-neutralization studies on leptospiral hemolysins from strains of two antigenically different serotypes, pomona and canicola, were conducted in sheep. A third strain of serotype hardjo that does not produce hemolysin and is antigenically distinct was included for control purposes. Concentrated hemolysins, prepared from supernatant fluids of canicola or pomona cultures, produced hemolytic anemia in sheep after intravenous injection. Sheep previously infected with hemolysin-producing strains were refractory to effects of homologous or heterologous hemolysins. On the other hand, infection with hardjo did not confer immunity to the action of hemolysins. Hemolysin-neutralizing antibodies were demonstrable in sheep previously infected with pomona or canicola only after challenge with homologous or heterologous hemolysins. Cross-neutralization between two hemolysins were demonstrable in vitro. Hemolysin-neutralizing antibody titers did not correlate with agglutinin titers. Concentrated supernatant fluid of the hardjo culture provoked toxic reactions predominantly in sheep previously infected with pomona or canicola. The causes of these untoward reactions were not determined.

Albuminuria↗
PubMedDate not supplied

The development of five animal feed reference materials, certified for their aflatoxin B1 content.

The development of three peanut meal and two compound feed reference materials and the certification of their aflatoxin B1 content is described. The materials were prepared and certified within the Measurements and Testing Programme of the Commission of the European Communities as part of a broad activity to improve accuracy and agreement of results of measurements on food and agriculture. RM 262 (peanut meal) was prepared from uncontaminated peanut products. RM 263 and RM 264 (peanut meals) were prepared from naturally contaminated peanuts which were blended with uncontaminated ones, to achieve the desired aflatoxin B1 mass fractions. RM 375 and RM 376 (compound feeds) were made by blending decontaminated dairy feed together with commercial feed ration and contaminated dairy feed with several feed compounds, respectively. Details are given of the preparation and the investigations to verify homogeneity and stability of the materials. The certification exercise was carried out by 17 laboratories using a variety of extraction and clean-up procedures. Most laboratories used liquid chromatography as the determinative step, although operating under a variety of chromatographic conditions. A few laboratories applied thin layer chromatography with densitometric quantification. Peanut meal RM 262 was certified as containing aflatoxin B1 at a mass fraction of < 3 micrograms/kg, RM 263 at 43.3 +/- 2.1 micrograms/kg and RM 264 at 204 +/- 10 micrograms/kg. Compound feed RM 375 was certified as containing aflatoxin B1 at a mass fraction of < 1 micrograms/kg and RM 376 at 9.2 +/- 0.5 micrograms/kg. The materials can be employed either to establish or confirm a calibration curve, or to check the performance of a method.

Aflatoxin B1↗
PubMedDate not supplied

Applications of diagnostic radiology to radiation oncology.

Despite advances in oncology, the local control of malignancies remains a formidable challenge. For the radiation oncologist, this challenge is approached by greater precision in the definition of the tumor and normal tissue with the intent of encompassing the former and excluding the latter from the high dose volume of treatment. Advances in diagnostic imaging have been incorporated into radiation therapy planning to achieve this goal. Recent developments in three dimensional treatment planning of CNS and pelvic malignancies illustrate the extent to which radiation oncology has come to rely on diagnostic imaging and the promise it offers for improvement in clinical care.

Central Nervous System Neoplasms↗