| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Björkman, Sven, et al.
(author)
-
Thermic and tremorogenic effects of thyroliberin (TRH) in reserpine-treated mice--the non-involvement of GABA-ergic mechanisms.
- 1981
-
In: Journal of Pharmacy and Pharmacology (JPP). - : Oxford University Press (OUP). - 0022-3573 .- 2042-7158. ; 33:9, s. 580-585
-
Journal article (peer-reviewed)abstract
- Administration of thyroliberin (TRH) to reserpinized mice causes tremor and counteracts the hypothermia in a dose-dependent fashion. The thyroliberin response is inhibited by gamma-hydroxybutyric acid (GHB) and baclofen, but not by other, more specific GABA-ergic agents, such as THIP, gamma-acetylenic GABA, and sodium valproate. Picrotoxin neither potentiates nor inhibits the thyroliberin actions. Nor are the thyroliberin effects dependent on cholinergic, monoaminergic or histaminergic mechanisms. The results repudiate a current hypothesis, that the peptide actions may be mediated by GABA-ergic pathways in the brain.
|
|
| 5. |
- Byström, Anders S, et al.
(author)
-
The nucleotide sequence of an Escherichia coli operon containing genes for the tRNA(m1G)methyltransferase, the ribosomal proteins S16 and L19 and a 21-K polypeptide
- 1983
-
In: EMBO Journal. - : Oxford University Press. - 0261-4189 .- 1460-2075. ; 2:6, s. 899-905
-
Journal article (peer-reviewed)abstract
- The nucleotide sequence of a 4.6-kb SalI-EcoRI DNA fragment including the trmD operon, located at min 56 on the Escherichia coli K-12 chromosome, has been determined. The trmD operon encodes four polypeptides: ribosomal protein S16 (rpsP), 21-K polypeptide (unknown function), tRNA-(m1G)methyltransferase (trmD) and ribosomal protein L19 (rplS), in that order. In addition, the 4.6-kb DNA fragment encodes a 48-K and a 16-K polypeptide of unknown functions which are not part of the trmD operon. The mol. wt. of tRNA(m1G)methyltransferase determined from the DNA sequence is 28 424. The probable locations of promoter and terminator of the trmD operon are suggested. The translational start of the trmD gene was deduced from the known NH2-terminal amino acid sequence of the purified enzyme. The intercistronic regions in the operon vary from 9 to 40 nucleotides, supporting the earlier conclusion that the four genes are co-transcribed, starting at the major promoter in front of the rpsP gene. Since it is known that ribosomal proteins are present at 8000 molecules/genome and the tRNA-(m1G)methyltransferase at only approximately 80 molecules/genome in a glucose minimal culture, some powerful regulatory device must exist in this operon to maintain this non-coordinate expression. The codon usage of the two ribosomal protein genes is similar to that of other ribosomal protein genes, i.e., high preference for the most abundant tRNA isoaccepting species. The trmD gene has a codon usage typical for a protein made in low amount in accordance with the low number of tRNA-(m1G)methyltransferase molecules found in the cell.
|
|
| 6. |
- Byström, Anders S, et al.
(author)
-
The structural gene (trmD) for the tRNA(m1G)methyltransferase is part of a four polypeptide operon in Escherichia coli K-12
- 1982
-
In: Molecular General Genetics. - : Springer-Verlag New York. - 0026-8925 .- 1432-1874. ; 188:3, s. 447-454
-
Journal article (peer-reviewed)abstract
- The trmD gene, which is the structural gene for the tRNA(m1G)-methyltransferase, is shown to be part of a polycistronic operon. A 4.6 kb SalI-EcoRI chromosomal DNA fragment contains the trmD gene (Byström and Björk 1982). Subclonings, deletion mapping and Tn5 insertions into plasmid pBY03 have established the gene organization of the trmD area on the Escherichia coli chromosome. The different plasmid derivatives were analysed for expression of protein products using the minicell system. Such analyses established the organisation of genes encoding six polypeptides to be SalI1-48 K-13 K-25 K-31 K-15 K-16 K-EcoRI1. The 31 K polypeptide was shown to be the tRNA(m1G)methyltransferase. The trmD operon encodes for four polypeptides; 13 K-25 K-31 K(trmD)-15 K and the direction of transcription is from 13 K (promoter proximal) to 15 K (promoter distal). However, there might be a weak internal promoter between the trmD gene and the gene encoding the 15 K product. The level of expression from this operon in the minicell system does not seem to follow normal polarity since we observed high expression of 13 K, 25 K, and 15 K products but low expression of the internal trmD gene.
|
|
| 7. |
- Bålfors, E., et al.
(author)
-
Droperidol inhibits the effects of intravenous ketamine on central hemodynamics and myocardial oxygen consumption in patients with generalized atherosclerotic disease
- 1983
-
In: Anesth Analg. ; 62:2, s. 193-7
-
Journal article (peer-reviewed)abstract
- A 2-mg/kg dose of ketamine was administered intravenously to 16 patients with generalized atherosclerotic disease. Eight patients were given 200 mu/kg of droperidol intravenously 10 min before ketamine administration; eight patients not given droperidol served as controls. Central hemodynamics, coronary flow (thermodilution technique) and myocardial oxygen, lactate, hypoxanthine, and catecholamine balances were studied. In control patients, ketamine increased mean blood pressure by 42%, pulmonary capillary wedge pressure by 144%, mean right atrial pressure by 60%, heart rate by 15%, and systemic vascular resistance by 40% without changes in cardiac index, stroke volume index, or left ventricular stroke work index. These data indicate that cardiac performance did not increase in parallel with the rise in afterload. However, the 50% increase in myocardial oxygen demand was associated with a 48% increase in coronary blood flow without changes in coronary vascular resistance or myocardial oxygen extraction. Augmented sympathetic activity was manifested by 397% and 164% increases in plasma levels of epinephrine and norepinephrine, respectively. The hemodynamic and cardiometabolic effects of ketamine were abolished when patients were pretreated with droperidol. The increase in plasma epinephrine levels was likewise inhibited by droperidol; significantly lower plasma norepinephrine levels also were observed. These findings suggest that droperidol inhibits the cardiovascular effects of ketamine by a centrally mediated reduction in sympathetic activity and by peripheral alpha receptor blockade.
|
|
| 8. |
- Dahlqvist, Solbritt Rantapää, et al.
(author)
-
HLA-B27 and involvement of sacroiliac joints in rheumatoid-arthritis
- 1984
-
In: Journal of Rheumatology. - 0315-162X .- 1499-2752. ; 11:1, s. 27-32
-
Journal article (peer-reviewed)abstract
- The frequency of radiographic signs of sacroiliac joint involvement (greater than or equal to 2 and greater than or equal to 3 according to the New York criteria) was significantly higher in 28 HLA-B27 positive patients with classical seropositive rheumatoid arthritis (RA), than in 28 B27 negative RA controls. The B27 positive RA patients had more subcutaneous nodules (p less than 0.01), worse functional class (p less than 0.05), and higher levels of erythrocyte sedimentation rate (ESR) (p less than 0.05) and haptoglobin (p less than 0.05). Sacroiliitis, independent of HLA-B27, was associated with higher levels of ESR (p less than 0.05), and with a higher frequency of positive ANA test (p less than 0.05). It is neither related to the functional class nor to the duration of the disease
|
|
| 9. |
- Gustafsson, I, et al.
(author)
-
Effect of preoperative paracetamol on pain after oral surgery.
- 1983
-
In: European Journal of Clinical Pharmacology. - 0031-6970 .- 1432-1041. ; 24:1, s. 63-65
-
Journal article (peer-reviewed)abstract
- A double-blind, randomized cross-over trial was carried out in 50 patients undergoing surgical removal of bilaterally impacted lower wisdom teeth. Surgery in each patient was performed twice and paracetamol 1000 mg was administered once preoperatively and once postoperatively. The time interval to additional analgesic intake and the pain intensity up to and at that time were assessed. There was no difference between the 2 treatments. It was concluded that preoperative paracetamol does not offer any clinical advantage in patients who undergo surgical removal of impacted lower wisdom teeth.
|
|
| 10. |
- Hjalmarsson, Karin J., et al.
(author)
-
Purification and characterization of transfer RNA (guanine-1)methyltransferase from Escherichia coli
- 1983
-
In: Journal of Biological Chemistry. - : American Society for Biochemistry and Molecular Biology. - 0021-9258 .- 1083-351X. ; 258:2, s. 1343-1351
-
Journal article (peer-reviewed)abstract
- The tRNA modifying enzyme, tRNA (guanine-1)methyltransferase has been purified to near homogeneity from an overproducing Escherichia coli strain harboring a multicopy plasmid carrying the structural gene of the enzyme. The preparation gives a single major band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme is probably a single polypeptide chain of molecular weight 32,000. The amino acid composition is presented and the NH2-terminal amino acid sequence was established to be H2N-Met-Trp-Ile-Gly-Ile-Ile-Ser-Leu-Phe-Pro. The enzyme has a pI of 5.2. The tRNA (guanine-1)-methyltransferase has a pH optimum of 8.0-8.5, an apparent Km of 5 microM for S-adenosylmethionine. S-adenosylhomocysteine is a competitive inhibitor for the enzyme with an apparent Ki of 6 microM. Spermidine or putrescine are not required for activity, but they stimulate the rate of methylation 1.2-fold with optima at 2 and 6 mM, respectively. Ammonium ion is not required and is inhibitory at concentrations above 0.15 M. Magnesium ion inhibited the activity at a concentration as low as 2 mM. Sodium and potassium ions were inhibitory at concentrations above 0.1 M. The molecular activity of tRNA (guanine-1)-methyltransferase was calculated to 10.0 min-1. It was estimated that the enzyme is present at 80 molecules/genome in cells growing with a specific growth rate of 1.0.
|
|
