Characterization of a cell-free translation system from Agrobacterium tumefaciens.
Explore the source record for details and available documents.
Agrobacterium tumefaciens↗
Biomedical subjects
R Iglesias
Publications and source records attributed to R Iglesias.
A scanning electron microscope study of Toxocara genettae Warren, 1972 (Ascaridae), with data on morphometric variation.
We have carried out a morphometric study of the ascaridoid nematode Toxocara genettae, parasite of the small intestine of the genet Genetta genetta, with the aid of scanning electron microscopy (SEM). Host specimens were trapped in Galicia, NW Spain. The most characteristic features of this nematode are the absence of cervical alae, replaced by narrow lateral crests running along the length of the body and the presence of a mucron at the end of the male tail. Other features of interest include the number of labial denticles (90-98 and 96-102 on the dorsal lip, 82-96 and 90-96 on the subventral lip of male and female, respectively), the width of the transverse striations (25-28 microns) and, in many of the specimens examined, the position of the precloacal median papilla at the base of a well-defined cuticular pit.
Animals↗
[The selection of resident physicians. The evaluation of their cardiology knowledge and of their pregraduate experience].
The purpose of this work was to assess the level of cardiological knowledge in a population of recently graduated physicians and to compare the examination results with pregraduation experiences. The results of the residency entrance examinations of 230 physicians from different universities were analyzed (Table 1). The examination consisted of 70 questions (69 by multiple choice and 1 of professional competence). The cardiovascular area was explored through 28 questions including basic and clinical subjects (Fig. 1). A qualitative and quantitative analysis of the examination was made based on difficulty and discrimination levels (Annex 1-2). A danger level was established when the answer involved a potential risk of death for the patient. Thirty percent of applicants passed the exam (60% of correct answers). Informative questions were easier than those of application and interpretation. A greater difficulty was evidenced with respect to questions in the clinical area (Fig. 3). A higher performance was noted in men, graduates from the University of Buenos Aires and those applicants with assistance and teaching experience. A remarkable positive correlation between average marks during the students career and the level of marks obtained in this exam (Fig. 2) was noted. Twenty-six percent of the physicians who failed gave potentially dangerous answers (Fig. 4). The examination results give us the opportunity to obtain information regarding features of university education.
Adult↗
Effect of fusidic acid on protein phosphorylation in several eukaryotic cell-free translation systems.
Explore the source record for details and available documents.
Animals↗
Effect of L-azetidine 2-carboxilic acid on the activity of the general amino-acid permease from Saccharomyces cerevisiae var. ellipsoideus.
Addition of the L-proline analogue L-azetidine 2-carboxylic acid to growing cultures of Saccharomyces cerevisiae var. ellipsoideus promoted fast deactivation of the general aminoacid permease, measured as L-valine uptake, without an immediate decrease in the growth rate. Cells preincubated with the analogue for 3 h were unable to restore either growth ability or general aminoacid permease activity in analogue-free medium. Eadie-Hofstee plots of L-valine uptake in the presence of the analogue are consistent with a strong reduction in the number of active molecules of the general amino-acid permease located in the plasma membrane. Inhibitory effects on protein synthesis were seen after preincubations of the yeast with the analogue for 3 h although a 30 min preincubation had no effect.
Amino Acid Transport Systems↗
Anatomical location of phosphorylcholine and other antigens on encysted Trichinella using immunohistochemistry followed by Wheatley's trichrome stain.
This work investigated the location on the parasite of Trichinella antigens recognized by the mouse immune system and the question as to which of them bear the epitope phosphorylcholine (PC). Wheatley's trichrome stain (initially developed for faecal smears) proved to be excellent for visualization of Trichinella structures, enabling four types of stichocyte to be distinguished. By applying this stain on infected muscle sections after immunocytochemistry using (a) anti-PC BH8 monoclonal antibodies, (b) serum from mice that had been infected twice in the presence of 0.05% thiabendazole (to prevent reproduction by adult females) and then bled on day 7 post-reinfection, (c) serum from infected mice that were bled on day 14 postinfection, or (d) serum from infected mice that were bled on day 42 postinfection, we found (1) that PC is an abundant structural epitope on the hypodermis/muscle, genital primordium and intestinal tract but is absent from the cuticle and stichosome; (2) that the principle secretory cells of adult worms are delta- and beta-stichocytes, whereas those of migrating and encysted L1 larvae are alpha-stichocytes; and (3) that Trichinella antigens recognized in the encysted phase of the parasite's life cycle are present in parasitized myofibres in the sarcoplasmic matrix and in the nucleoplasm of hypertrophic nuclei. The significance of these findings is discussed.
Animals↗
Changes in sensitivity of in vitro rat brain protein synthesis to the acute action of ethanol and isopropanol as a consequence of the long-term ingestion of isopropanol.
Long-term treatment of rats with isopropanol in the drinking water results in a change or process of adaptation occurring in in vitro brain protein synthesis which increases the resistance of the ribosomal machinery to the acute effect of either ethanol or isopropanol. Such an increase was observed both in the system coded by endogenous messenger and in the system coded by polyuridylic acid. In both translation systems, the adaptation seems to affect the ribosomal step of polypeptide chain elongation. The increase in resistance to the alkanols apparently did not affect the inhibitory action of puromycin, fusidic acid and cycloheximide on the ribosome.
Adaptation, Physiological↗
Effect of long-term n-butanol ingestion on rat brain polypeptide synthesis directed by endogenous messengers.
Long-term ingestion of sublethal n-butanol doses by rats led to a noteworthy increase in the resistance of in vitro brain ribosomal function to the acute inhibitory action of ethanol and isopropanol. Withdrawal of n-butanol did not change this adaptation process immediately. The step affected seems to be the elongation of polypeptide chains. The dependence of in vitro translation on incubation temperature was affected by the adaptation process, the translation system of chronic animals being less stimulatable than that of control animals at low temperature.
1-Propanol↗
Helminth parasites in some Spanish bats.
Nineteen bats of the species Rhinolophus ferrumequinum, R. hipposideros, Myotis myotis, M. nattereri, Pipistrellus pipistrellus, Barbastella barbastellus, Eptesicus serotinus and Plecotus auritus captured in N. W. Spain in 1983-85 were found to contain the following helminth parasites: Mesotretes peregrinus (found in 4 host species and making up 31% of all helminths); Plagiorchis vespertilionis (10.5%, in 2 host species); Strongylacantha glycirrhiza, Molinostrongylus alatus, Molineidae gen. sp., Capillariidae gen. sp., Hymenolepis acuta, Cestoda gen. sp. and Trematoda gen. sp. I and II (5.2% in 1 host species).
Animals↗
Lung and hearth nematodes in some Spanish mammals.
Thirteen host species belonging to the orders Rodentia, Insectivora and Carnivora from various localities in Galicia (NW Spain) were examined for heart and lung parasites. The following species were found: Parastrongylus dujardini (5.5%) in Apodemus sylvaticus, Crenosoma striatum in Erinaceus europaeus (83%), Angiostrongylus vasorum, Crenosoma vulpis and Eucoleus aerophilus in Vulpes vulpes (3, 3.46 and 0.50%, respectively), Crenosoma taiga in Putorius putorius (100%) and Crenosoma sp. in Meles meles (25%). In Crocidura russula nematode larvae were found (3.3%). Mus musculus, Rattus norvegicus, Rattus rattus, Talpa caeca, Sorex araneus, Genetta genetta and Canis lupus were not parasitized by lung or heart parasites.
Animals↗
Ontogeny and perinatal modulation of gene expression in rat brown adipose tissue. Unaltered iodothyronine 5'-deiodinase activity is necessary for the response to environmental temperature at birth.
We have performed a sequential study on the abundance of the mRNA for uncoupling protein (UCP), subunit II of cytochrome-c oxidase (COII) and lipoprotein lipase in brown adipose tissue during the fetal and postnatal periods. Moreover, we have determined whether these parameters can be modulated by ambient temperature in the early hours after birth, and at which point in development this sensitivity first appears. UCP gene expression in the fetal and neonatal period has particular features when compared with overall mitochondriogenesis (COII mRNA expression) or with the expression of lipoprotein lipase mRNA. There is a specific induction of UCP gene expression between days 18 and 19 of pregnancy followed by a specific increase of UCP gene expression in utero and a further increase after birth. The acquisition of the physiological apparatus capable of the response to UCP and lipoprotein lipase gene expression to the environmental temperature is not achieved until the last day of fetal development. This result suggests that mechanisms of beta-adrenergic modulation of gene expression in brown fat are already established at birth. From an experiment on iopanoic acid treatment of pregnant mothers, it was concluded that iodothyronine 5'-deiodinase activity is not necessary for the expression of the mRNAs for UCP, COII and lipoprotein lipase in the fetus whereas it is necessary for the acquisition of temperature sensitivity to these parameters at birth.
Adipose Tissue, Brown↗
Adaptation of in vitro rat brain protein synthesis to long-term ingestion of n-butanol.
Long-term treatment of rats with n-butanol leads to a change in in vitro brain protein synthesis which increases the resistance of this process to either ethanol or isopropanol. The change seems to be related to ribosomal events since the synthesis of aminoacyl-tRNA was not affected in the same conditions.
1-Butanol↗
Lipoprotein lipase mRNA expression in brown adipose tissue: translational and/or posttranslational events are involved in the modulation of enzyme activity.
Lipoprotein lipase mRNA abundance in rat brown adipose tissue increases during the first 24 h of cold exposure. Lipoprotein lipase mRNA levels do not change in brown fat throughout pregnancy and lactation, whereas enzyme activity is significantly lowered. After 5 h of acute cold or noradrenaline administration there is a 2-fold increase in lipoprotein lipase mRNA abundance, whereas lipoprotein lipase activity is stimulated to more than 6-fold the basal values. It is concluded that translational and/or posttranslational mechanisms are involved in the noradrenergic modulation of lipoprotein lipase activity in brown fat.
Acclimatization↗
Differential D-glucose requirements of the general amino-acid permease and protein synthesis in Saccharomyces cerevisiae var. ellipsoideus.
The dependence of the general aminoacid permease and protein synthesis on the availability of D-glucose as energy source was studied. Stimulation by the sugar was immediate once added to the cell suspensions and seems to be mediated by energy derived directly from glycolysis. The general aminoacid permease was saturated linearly with D-glucose whereas protein synthesis was saturated sigmoidealy requiring much higher concentration of the sugar than the general aminoacid permease.
Amino Acid Transport Systems↗
Messenger-dependent action of guanylylimidodiphosphate and translation inhibitors on rat brain polypeptide synthesis.
The effects of the Guanosine 5'-triphosphate analog guanylylimidodiphosphate and several antibiotics on protein synthesis in a cell-free system from rat brain were investigated as a function of the template used. Polypeptide chain elongation was promoted by the analog only in the system coded by the endogenous template but not when coded by polyuridylic acid. The effects of the antibiotics were also dependent on the template used. This suggest that the template conditioned the ribosomal conformation which determine the inhibitory effect of the antibiotics.
Animals↗
Influence of the structure of alkanols on their inhibition of protein synthesis in Saccharomyces cerevisiae var. ellipsoideus.
The effects of several short chain alcohols on protein synthesis by intact Saccharomyces cerevisiae var. ellipsoideus cells were studied. The results show that the relative inhibitory potencies correlate well with the size of the carbon backbone, thus suggesting that a hydrophobicity-related effect is involved in the inhibitory action of these alcohols. Additionally, the branching nature of the carbon backbone contributes to determining the action of the alcohol, as proved by the relative potencies of the four-carbon alcohol series.
Alcohols↗
Adaptative decrease in expression of the mRNA for uncoupling protein and subunit II of cytochrome c oxidase in rat brown adipose tissue during pregnancy and lactation.
Uncoupling-protein (UCP) mRNA expression is decreased to 15% of virgin control levels between days 10 and 15 of pregnancy, and remains at these low values during late pregnancy and lactation. Abrupt weaning of mid-lactating rats causes a slight but significant increase in UCP mRNA. Expression of mRNA for subunit II of cytochrome c oxidase (COII) decreased to half that of virgin control in late pregnancy and during lactation. Whereas COII mRNA expression is in step with the known modifications of brown-fat mitochondria content during the breeding cycle of the rat, UCP mRNA expression appears to be diminished much earlier than the mitochondrial proton-conductance-pathway activity. On the other hand, the reactivity of brown fat to increase expression of UCP and COII mRNAs in response to acute cold or noradrenaline treatment is not impaired during lactation.
Adipose Tissue, Brown↗
Iodothyronine 5'-deiodinase activity as an early event of prenatal brown-fat differentiation in bovine development.
Iodothyronine 5'-deiodinase activity appears to be a type I enzyme in bovine brown adipose tissue, on the basis of its high Km for 3,3',5'-tri-iodothyronine ('reverse T3') (in the micromolar range) and sensitivity to propylthiouracil inhibition. This enzyme activity is already detectable in perirenal adipose tissue of bovine fetuses in the second month of gestation, reaches peak values around the seventh month of fetal life, declines before birth, becomes lower after parturition and finally undetectable in the adult cow. Iodothyronine 5'-deiodinase activity is present in the pericardic, peritoneal and intermuscular adipose depots of the neonatal calf, but it is always undetectable in the subcutaneous adipose tissue. It is concluded that iodothyronine 5'-deiodinase is a specific feature of brown fat in the bovine species that is not shared by white adipose tissue. white adipose tissue. Peak values of 5'-deiodinating activity appear as an early event in the prenatal differentiation programme of bovine brown-fat cells as they occur when uncoupling-protein-gene expression first starts.
Adipose Tissue, Brown↗