| 1. |
- Blomqvist, S, et al.
(author)
-
Early post-traumatic changes in hemodynamics and pulmonary ventilation in alcohol-pretreated pigs
- 1987
-
In: Journal of Trauma. - 0022-5282. ; 27:1, s. 40-44
-
Journal article (peer-reviewed)abstract
- Time relations among trauma, pulmonary and systemic circulation, and lung function were studied in pigs. Eleven animals (b.w. 25-30 kg) were investigated under balanced anesthesia. Ventilation was mechanically controlled. Hemodynamics, pulmonary ventilation, and gas exchange were serially recorded. Seven animals were pretreated with 40% ethanol in saline and four with saline only. Ninety minutes after the ingestion of alcohol or saline, the animals were subjected to a standardized soft-tissue trauma. Cardiac output decreased significantly 2 minutes after trauma and remained low in both groups throughout the observation period of 30 minutes. Pulmonary vascular resistance was significantly increased in the alcohol-pretreated group but was virtually unchanged in the control animals. Systemic vascular resistance was similarly reduced in the two groups. Total compliance was somewhat lower in alcohol-pretreated animals and 10 minutes after the trauma arterial oxygen tension was significantly lower in the alcohol group than in control animals. Carbon dioxide elimination was reduced after trauma in both groups. It is concluded that pulmonary vascular response increased and that total pulmonary compliance is somewhat decreased shortly after trauma in the alcohol group while gas exchange is almost unchanged. The results indicate a negative interaction between alcohol and trauma
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| 2. |
- Dunnett, S B, et al.
(author)
-
Intracerebral grafting of neuronal cell suspensions. IV. Behavioural recovery in rats with unilateral implants of nigral cell suspensions in different forebrain sites
- 1983
-
In: Acta Physiologica Scandinavica. ; Suppl. 522, s. 29-38
-
Journal article (peer-reviewed)abstract
- Single and multiple implants of nigral cell suspensions were grafted to the forebrains of rats with unilateral 6-hydroxydopamine-induced dopamine denervations. Control lesions alone induced a marked behavioural asymmetry, as assessed by amphetamine- and apomorphine-induced rotation, sensorimotor tests and side bias in an unbaited T-maze, and the animals were hyperactive to a low dose of apomorphine. Single suspension placements into different denervated striatal regions were capable of reversing the behavioural asymmetries dependent upon the specific placement for each test. Multiple suspension grafts were capable of reversing all behavioural asymmetries, and additionally abolished the supersensitive hyperactivity to apomorphine. By contrast, single suspension grafts placed into the substantia nigra or lateral hypothalamus had no detectable effect on any functional measure. The results indicate that nigral suspension grafts can be at least as effective as solid grafts in reversing the functional deficits induced by dopamine denervation, provided that placements are selected within appropriate dopamine terminal regions of the forebrain (e.g. caudate-putamen or nucleus accumbens).
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| 3. |
- Dunnett, S B, et al.
(author)
-
Intracerebral grafting of neuronal cell suspensions. V. Behavioural recovery in rats with bilateral 6-OHDA lesions following implantation of nigral cell suspensions.
- 1983
-
In: Acta Physiologica Scandinavica. ; Suppl. 522, s. 39-48
-
Journal article (peer-reviewed)abstract
- Bilateral 6-hydroxydopamine-induced lesions of the ascending forebrain dopamine neurones induce a behavioural syndrome in rats which includes profound aphagia, adipsia, akinesia and bilateral sensorimotor neglect. Such animals will die unless maintained by intragastric feeding. Three experiments are reported in which we have attempted to ameliorate this syndrome with single or multiple placements of nigral cell suspensions into the forebrains of rats with bilateral dopamine depletions. Although the grafts were efficient in reversing the sensorimotor and akinetic impairments, and produced a significant increase in eating, the grafted rats remained hypophagic and adipsic. The results indicate that although many components of the bilateral dopamine denervation syndrome can be reversed by intrastriatal nigral suspension grafts, the severe eating and drinking deficits remain unameliorated.
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| 4. |
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| 5. |
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| 6. |
- Uhrberg, R I G, et al.
(author)
-
Well-Known "Surface State" on Si(111)2×1 Identified as a Bulk Contribution
- 1984
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 52:25, s. 2265-2268
-
Journal article (peer-reviewed)abstract
- Using polarization-dependent angle-resolved photoemission we show that two dominating structures in the photoemission spectra are due to direct transitions from the uppermost two valence bands in silicon. The final-state band for these transitions at photon energies 10.2-21.2 eV is found to have free-electron-like dispersion. Our results imply that that threefold-symmetry emission often assigned to back-bond surface states on Si(111)2×1 is really due to bulk photoemission.
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| 7. |
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| 8. |
- Andrén, Lennart, 1946, et al.
(author)
-
Diltiazem in hypertensive patients with type II diabetes mellitus.
- 1988
-
In: The American journal of cardiology. - : Elsevier BV. - 0002-9149. ; 62:11
-
Journal article (peer-reviewed)abstract
- Twenty-three patients with essential hypertension and diabetes mellitus type II were treated with the calcium antagonist diltiazem (120 to 180 mg twice daily). The mean dose was 307 mg/day. The study was a double-blind, placebo-controlled, crossover design. All measurements were performed 12 to 14 hours after drug intake. Blood pressure, heart rate and forearm blood flow were measured noninvasively. Platelet function was studied by measuring adenosine diphosphate-induced platelet aggregation and the platelet specific proteins, beta thromboglobulin and platelet factor 4. Thromboxane B2 formation in serum and the plasma concentration of diltiazem and its metabolites N-demethyldiltiazem, deacetyldiltiazem and N-demethyldeacetyldiltiazem were measured both during placebo and diltiazem treatment. Diabetic control was evaluated by following HbA1C, fasting blood glucose and urinary glucose. Diltiazem reduced both systolic and diastolic (supine and standing) blood pressure significantly. Forearm blood flow was significantly increased by 32%, p less than 0.05. Supine heart rate decreased significantly, while no such change was seen in the standing position. No significant changes were observed in platelet function during diltiazem treatment. There was no relation between the observed blood pressure reduction and the plasma concentration of diltiazem or its metabolites. A positive correlation between the change in heart rate and the metabolite N-demethyldeacetyldiltiazem was observed (r = 0.647, p = 0.005). Three patients were excluded during diltiazem treatment (skin exanthema, headache and atrial fibrillation) and 1 during placebo treatment (angina pectoris). No negative effect on diabetes control was observed. Thus, diltiazem could be used for treatment of hypertension in diabetic patients.
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| 9. |
- Anveskog, L., et al.
(author)
-
Development of Activities - Standard Application Packages according SIV to help you make better use of standard application packages in your organization : Verksamhetsutveckling - Standardsystem enligt SIV för att du skall kunna utnyttja standardsystem bättre i din verksamhet
- 1986
-
Reports (other academic/artistic)abstract
- The report is published in an English and Swedish version.Rapporten finns utgiven på svenska och engelska. ------------------------------------------------There is a need for a systematic way of working when planning for standard application packages in organizations. We have tried to develop a method for this field - the SIV method (Standard Application Packages in Organizations, in Swedish: Standardsystem I Verksamheter). The SIV method takes the customer's situation as a starting point - a customer view. Furthermore, occasions have been described where a dialogue between the customer and the vendor is necessary, e.g. demonstrations and negotiations. The SIV method gives a survey of the field with emphasis on adaptation of activities and standard application packages to each other.This report is focusing on "adaptation" of standard application packages. A similar report has been done for "choice" of standard application packages.------------------------------------------------ Det finns behov av ett systematiskt arbetssätt vid planering av standardsystem för verksamheter. Vi har försökt utveckla en metodik för detta område - SIV (Standardsystem I Verksamheter). SIV-metodiken tar utgångspunkt i kundens situation - ett kundperspektiv.Vidare anges tillfällen när det behövs en dialog mellan kund och leverantör, t.ex. demonstrationer och förhandlingar. SIV-metodiken ger en översikt av området med betoning på anpassning av verksamhet och standardystem mot varandra.Denna rapport behandlar "anapssning" av standardsystem. En liknande rapport har tagits fram för "val" av standardystem.------------------------------------------------
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| 10. |
- Anveskog, L., et al.
(author)
-
Verksamhetsutveckling - Att anpassa standardsystem
- 1983
-
Book (peer-reviewed)abstract
- Syftet med standardsystem är att tjäna tid och pengar. Ett standardsystem kan även ge nya möjligheter att effektivisera en verksamhet. Finns det några problem vid anskaffning av standardsystemet? Ja, alltför ofta väljs standardsystem på ett för dåligt underlag om verksamhetens krav och behov. Sedan underskattar man resurserna för anpassning av standardsystem och verksamhet till varandra.Denna bok behandlar en metod för att anpassa standardysstem i ett företags verksamhet (SIV-metoden). Boken innehåller praktikfall från Alfa-Laval och Philips som exempel på metodanvändningen. Boken vänder sig till personer som arbetar med att förändra standardsystem och det egna verksamhetsområdet mot varandra med de konsekvenser detta kan innebära.Ibland behöver vi göra ett förval bland urvalet av standardsystem på marknaden. En metod för detta presenteras i boken: " Verksamhetsutveckling - Att välja standardsystem" (Studenlitteratur, 1984) som kan ses som ett komplement till denna bok.Boken var förpublicerad som V-rapport V-4201, Institutet för Verksamhetsutveckling (Institut V) vid Handelshögskolan i Stockholm (1982-02-26)
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| 11. |
- Berg, S., et al.
(author)
-
Analysis of airborne organic lead
- 1984
-
In: Biological effects of organolead compounds. - Boca Raton, FL : CRC Press. - 0849353092 ; , s. 278-
-
Book chapter (other academic/artistic)
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| 12. |
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| 13. |
- Björk, Glenn R, et al.
(author)
-
Prevention of translational frameshifting by the modified nucleoside 1-methylguanosine
- 1989
-
In: Science. - 0036-8075 .- 1095-9203. ; 244:4907, s. 986-989
-
Journal article (peer-reviewed)abstract
- The methylated nucleoside 1-methylguanosine (m1G) is present next to the 3' end of the anticodon (position 37) in all transfer RNAs (tRNAs) that read codons starting with C except in those tRNAs that read CAN codons. All of the three proline tRNA species, which read CCN codons in Salmonella typhimurium, have been sequenced and shown to contain m1G in position 37. A mutant of S. typhimurium that lacks m1G in its tRNA when grown at temperatures above 37 degrees C, has now been isolated. The mutation (trmD3) responsible for this methylation deficiency is in the structural gene (trmD) for the tRNA(m1G37)methyltransferase. Therefore, the three proline tRNAs in the trmD3 mutant have an unmodified guanosine at position 37. Furthermore, the trmD3 mutation also causes at least one of the tRNAPro species to frequently shift frame when C's are present successively in the message. Thus, m1G appears to prevent frameshifting. The data from eubacteria apply to both eukaryotes and archaebacteria.
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| 14. |
- Björklund, Anders, et al.
(author)
-
Intracerebral grafting of neuronal cell suspensions. I. Introduction and general methods of preparation.
- 1983
-
In: Acta Physiologica Scandinavica. ; Suppl. 522, s. 1-7
-
Journal article (peer-reviewed)abstract
- The steps involved in the grafting of mesencephalic and septal embryonic tissue in the form of dissociated cell suspensions are described in detail. This includes dissection of the donor embryos, incubation in trypsin, mechanical dissociation, and stereotaxic injection into the brains of adult recipient rats. Some of the technical problems and limitations are discussed.
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| 15. |
- Björklund, Anders, et al.
(author)
-
Intracerebral grafting of neuronal cell suspensions. II. Survival and growth of nigral cells implanted in different brain sites
- 1983
-
In: Acta Physiologica Scandinavica. ; Suppl. 522, s. 9-18
-
Journal article (peer-reviewed)abstract
- Dissociated dopamine-rich cell suspensions were prepared from the ventral mesencephalon of rat embryos and injected in one or several sites in striatal and non-striatal regions in the dopaminergically denervated brain of adult rats. While the grafts survived well in all sites, the dopamine fibre outgrowth was markedly different depending on whether the grafts occurred in an area normally innervated by the mesencephalic dopamine neurones (i.e. neostriatum or nc. accumbens) or in areas not normally innervated by these neurones (i.e. parietal cortex, lateral hypothalamus or substantia nigra). Moreover, in grafts placed at different sites along the trajectory of the nigrostriatal pathway the outgrowing fibres remained confined to the graft, and there was little evidence that the implanted neurones could elongate their axons along the pathway of the nigrostriatal tract to reach the striatum from a distance. Thus, the intracerebral suspension grafts provided efficient reinnervation of a denervated target only when placed in the immediate vicinity of the target area. The results of multiple graft placements indicate that a relatively complete restoration of a lost innervation should be possible to achieve in large areas of the brain, such as the striatal complex, with the suspension grafting technique.
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| 16. |
- Björklund, Anders, et al.
(author)
-
Intracerebral grafting of neuronal cell suspensions. VI. Survival and growth of intrahippocampal implants of septal cell suspensions
- 1983
-
In: Acta Physiologica Scandinavica. ; Suppl. 522, s. 49-58
-
Journal article (peer-reviewed)abstract
- The survival and growth of intrahippocampal septal suspension grafts were investigated by acetylcholine esterase (AChE) histochemistry in animals with lesions of the intrinsic septohippocampal cholinergic pathways. AChE was demonstrable in the grafts after the first postoperative week, and AChE-positive fibres were seen to extend into the host hippocampus by 3 weeks. Rapid fibre outgrowth occurred between 3 weeks and 3 months after grafting, and continued at a slower rate thereafter. By 6 months a fairly complete reinnervation of the initially denervated hippocampus was achieved in most specimens, and this persisted at 14 months, the longest postoperative time analysed. A comparison between the development of the AChE-positive neurones in the suspension grafts with that seen during ontogeny in situ suggested that the grafted neurones lagged behind normal development by at least 1 week. Similar to our previous observations on septal grafts implanted as solid tissue pieces, the pattern of the newly-formed AChE-positive innervation in the host hippocampal formation, established from the septal suspension grafts, was remarkably similar to that of the normal AChE-positive septal innervation. This pattern became established as soon as the graft-derived fibres first grew in, suggesting that the ingrowing axons extended and ramified preferentially into those hippocampal subfields which normally receive an AChE-positive innervation from the septal-diagonal band area.
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| 17. |
- Björklund, Anders, et al.
(author)
-
Intracerebral grafting of neuronal cell suspensions. VII. Recovery of choline acetyltransferase activity and acetylcholine synthesis in the denervated hippccampus reinnervated by septal suspension implants
- 1983
-
In: Acta Physiologica Scandinavica. ; Suppl. 522, s. 59-66
-
Journal article (peer-reviewed)abstract
- The time-course and magnitude of fibre outgrowth from septal suspension grafts injected into the previously denervated hippocampal formation was monitored by measurements of choline acetyltransferase (ChAT), and the activity of the grafted neurons was assessed by measurements of [14C]acetylcholine (ACh) synthesis from [14C]glucose in vitro. Graft-derived ChAT activity was barely detectable 10 days after grafting, but increased sharply between 10 days and 1 month in the areas of the hippocampus located close to the septal implants. By 6 months ChAT activity was restored to near normal levels in all segments of the previously denervated hippocampus. The overall hippocampal [14C]ACh synthesis was also restored to normal levels in the grafted animals, and estimates of the ACh turnover rate suggested that the transmitter machinery of the newly established "septo-hippocampal" connections operated at a rate similar to that of the intrinsic septohippocampal pathway. The intrahippocampal septal suspension grafts, similar to the intrastriatal nigral grafts, thus seem to be capable of maintaining function at a relatively "physiological" level despite their abnormal positions.
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| 18. |
- Byström, Anders S., et al.
(author)
-
A functional analysis of the repeated methionine initiator tRNA genes (IMT) in yeast
- 1989
-
In: Molecular General Genetics. - 0026-8925 .- 1432-1874. ; 216:2-3, s. 276-286
-
Journal article (peer-reviewed)abstract
- Standard laboratory yeast strains have from four to five genes encoding the methionine initiator tRNA (IMT). Strain S288C has four IMT genes with identical coding sequences that are colinear with the RNA sequence of tRNA(IMet). Each of the four IMT genes from strain S288C is located on a different chromosome. A fifth IMT gene with the same coding sequence is present in strain A364A but not in S288C. By making combinations of null alleles in strain S288C, we show that each of the four IMT genes is functional and that tRNA(IMet) is not limiting in yeast strains with three or more intact genes. Strains containing a single IMT2, 3 or 4 gene grow only after amplification of the remaining IMT gene. Strains with only the IMT1 gene intact are viable but grow extremely slow; normal growth is restored by the addition of another IMT gene by transformation, providing a direct test for IMT function.
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| 19. |
- Byström, Anders S, et al.
(author)
-
Differentially expressed trmD ribosomal protein operon of Escherichia coli is transcribed as a single polycistronic mRNA species
- 1989
-
In: Journal of Molecular Biology. - : Academic Press. - 0022-2836 .- 1089-8638. ; 208:4, s. 575-586
-
Journal article (peer-reviewed)abstract
- The trmD operon is a four-cistron operon in which the first and fourth genes encode ribosomal proteins S16 (rpsP) and L19 (rplS), respectively. The second gene encodes a 21,000 Mr polypeptide of unknown function and the third gene (trmD) encodes the enzyme tRNA(m1G37)methyltransferase, which catalyzes the formation of 1-methylguanosine (m1G) next to the 3' end of the anticodon (position 37) of some tRNAs in Escherichia coli. Here we show under all regulatory conditions studied, transcription initiates at one unique site, and the entire operon is transcribed into one polycistronic mRNA. Between the promoter and the first gene, rpsP, an attenuator-like structure is found (delta G = -18 kcal; 1 cal = 4.184 J), followed by four uridine residues. This structure is functional in vitro, and terminates more than two-thirds of the transcripts. The different parts of the trmD operon mRNA decay at a uniform rate. The stability of the trmD mRNA is not reduced with decreasing growth rate, which is in contrast to what has been found for other ribosomal protein mRNAs. Furthermore, earlier experiments have shown the existence of differential expression as well as non-co-ordinate regulation within the operon. Our results are consistent with the regulation of the trmD operon being due to some mechanism(s) operating at the post-transcriptional level, and do not involve differential degradation of different mRNA segments, internal promoters or internal terminators.
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| 20. |
- 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.
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| 21. |
- 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.
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| 22. |
- Dalboge, H, et al.
(author)
-
High-level expression of active human cystatin C in Escherichia coli
- 1989
-
In: Gene. - 1879-0038. ; 79:2, s. 325-332
-
Journal article (peer-reviewed)abstract
- Expression of the human cysteine proteinase inhibitor, cystatin C (CysC) in the cytoplasm of Escherichia coli was studied using a cDNA fragment encoding the cysteine proteinase inhibitor controlled by the phage λ pImage /cI857 system. The yield of CysC was low, probably due to proteolytic degradation. By fusing the cysC cDNA to a DNA fragment encoding the signal peptide of the E. coli outer membrane protein A, it was possible to produce a substantial amount of CysC in the periplasm. The processing of the signal peptide was shown to be quantitative and to result in CysC with the correct N-terminal amino acid. Yields higher than 1000 μg CysC/ml can be obtained by initiating the product formation at a moderate temperature (40 °C) late in an optimized fermentation process. A method that gives selective extraction of the periplasmic proteins and at the same time stabilizes CysC has been used.
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| 23. |
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| 24. |
- Forsman, Anders, et al.
(author)
-
Maintenance of colour polymorphism in adder populations, Vipera berus L.: a test of a popular hypothesis
- 1987
-
In: Oikos. ; 50, s. 13-16
-
Journal article (peer-reviewed)abstract
- Accordingt o a currenth ypothesis,t he colourp olymorphismin populationso f the adder,Vipera berus L., is maintained by a thermal superiority of melanistic snakes,which enables them to grow more quickly than normally coloured ones. Since largermales are superior in sexual combats, and larger females get more offspring, thisclearly should favour the melanistic trait. On the other hand, melanistic individualsare believed to suffer a higher predation pressure due to their more conspicuous appearance.T he predictionf rom this hypothesisi s that melanistici ndividualso n averageshould be largert han normali ndividualsi n mixed populations.T his predictionwas tested on adders captured on several small islands in the Stockholm archipelago(N 59°20';E 19°20').N o significantd ifferencew as found in weight, lengtho r weight/length ratio between melanistic and normally coloured male adders. Neither slopenor elevation of the regression lines of length on weight differed. Thus, the hypothesiswas not supported by our data.
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| 25. |
- Gage, F H, et al.
(author)
-
Intracerebral grafting of neuronal cell suspensions. VIII. Cell survival and axonal outgrcwth of dcpaminergic and cholinergic cells in the aged brain.
- 1983
-
In: Acta Physiologica Scandinavica. ; Suppl. 522, s. 67-75
-
Journal article (peer-reviewed)abstract
- Neuronal cell suspensions prepared from the ventral mesencephalon and the septal-diagonal band area of rat embryos were implanted into the depth of the intact neostriatum or hippocampus of 21-23 month old female rats. Graft survival, assessed 3-4 months after grafting, was comparable to that seen in our previous studies of young adult recipients. Fibre outgrowth into the host brain was evaluated in animals which were subjected to lesions of the intrinsic nigrostriatal or septohippocampal system 6-10 days before killing. Dense dopamine fibre outgrowth was seen within a zone of up to about 1 mm radius around the nigral implants, and dense growth of acetylcholine esterase (AChE) positive fibres occurred up to about 2 mm away from the septal implants. The overall magnitude of fibre outgrowth was less than that generally seen in previously denervated targets in young adult recipients, but it appeared to be as extensive as in young recipients when the grafts are placed in non-denervated targets. The distribution of the AChE-positive fibres from the septal implants in the host hippocampus suggested that the pattern found in the non-denervated target of the aged recipients was more diffuse, and partly different, from normal, and that age-dependent synapse loss in intrinsic connections may influence the patterning of the graft-derived innervation.
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| 26. |
- Grubb, Anders, et al.
(author)
-
Production of an amino acid sequence-specific antiserum against human amyloid A (AA) and serum amyloid A (SAA) protein
- 1987
-
In: Scandinavian Journal of Clinical and Laboratory Investigation. - 0036-5513. ; 47:6, s. 619-626
-
Journal article (peer-reviewed)abstract
- The hydrophilic nonapeptide Ser-Asp-Ala-Arg-Glu-Asn-Ile-Gln-Arg, identical with residues 59-67 of human amyloid protein A (AA) and serum amyloid protein A (SAA), was covalently bound via its carboxyl-terminal end to the carrier-protein keyhole limpet haemocyanin. The complex was injected subcutaneously into ten rabbits. All rabbits produced antisera which, unabsorbed, were specific for AA and SAA. The antisera and their isolated peptide specific antibodies were performance-tested and found to be excellent for demonstration of AA and SAA in immunoblotting and immunohistochemical techniques but unsuitable for immunoprecipitation. Since it is difficult to produce AA- and SAA-specific antisera by procedures earlier described and commercial supplies of good such reagents are unavailable, the easy production of sequence-specific such antisera will facilitate more extended studies of the corresponding antigens for diagnostic and scientific purposes.
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| 27. |
- 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.
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| 28. |
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| 29. |
- Kurtz, Richard L., et al.
(author)
-
Core-excitoninduced desorption from MgO
- 1987
-
In: Physical Review B (Condensed Matter). - 0163-1829. ; 35:14, s. 7794-7797
-
Journal article (peer-reviewed)abstract
- Core-exciton-induced desorption of O and H from MgO(100) and MgO(111) has been observed using photon excitation energies spanning the O K edge. Electron-yield data from partially oxidized Mg implies that these states are localized in the near-surface region. O and H desorption results from the decay of different O core-exciton states as well as the states produced by interband transitions. The O excitonic levels are interpreted in terms of their related atomic origin.
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| 30. |
- Palsdottir, A, et al.
(author)
-
Study of restriction fragment length polymorphism in the cystatin C gene of elderly patients with dementia and aged Down's syndrome patients
- 1989
-
In: Progress in Clinical and Biological Research. - 0361-7742. ; 317, s. 235-239
-
Journal article (peer-reviewed)abstract
- Using a full length cystatin C cDNA probe and the Alu I restriction enzyme a total of 33 patients with senile dementia, Alzheimer type and 31 Down's syndrome patients have been investigated for the presence of the 630 bp Alu I restriction fragment length polymorphism in the cystatin C gene detected in Icelandic patients with hereditary cystatin C amyloid angiopathy. Results showed that all the patients had normal cystatin C fragment length of 600 bp.
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| 31. |
- Schmidt, R H, et al.
(author)
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Intracerebral grafting of neuronal cell suspensions. III. Activaty of intrastriatal nigral suspension implants as assessed by measurements of dopamine synthesis and metabolism
- 1983
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In: Acta Physiologica Scandinavica. ; Suppl. 522, s. 19-28
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Journal article (peer-reviewed)abstract
- The activity of intrastriatal grafts of nigral cell suspensions has been monitored biochemically, using radioenzymatic assays of dopamine, its major acidic metabolite, DOPAC, and DOPA accumulation after DOPA-decarboxylase inhibition. Implants of 4-9 microliter of nigral cell suspension restored striatal DA levels by an average of 13-18%, with the highest individual values reaching about 50% of control. DOPAC was restored from about 5% in the lesioned controls to about 20% of normal in the grafted animals. The DOPAC: DA ratios and the DOPA accumulation measures indicated that the grafted DA neurons were spontaneously active and that the transmitter turnover rate was on the average some 50-100% higher than the intact intrinsic nigrostriatal DA neurones. These results thus provide evidence that the intrastriatal nigral suspension grafts are capable of restoring dopaminergic neurotransmission in the previously denervated striatum.
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| 32. |
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| 33. |
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| 34. |
- Werner, Olof, et al.
(author)
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Carbon dioxide elimination from each lung during endobronchial anaesthesia. Effects of posture and pulmonary arterial pressure
- 1984
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In: British Journal of Anaesthesia. - 1471-6771. ; 56:9, s. 995-1001
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Journal article (peer-reviewed)abstract
- The ventilation and carbon dioxide elimination of each lung, and pulmonary arterial pressure, were studied in 17 patients during the early phases of anaesthesia for pulmonary surgery. The patients were ventilated mechanically to moderate hypocapnia. Expired tidal volume and carbon dioxide elimination rate of the lung to be operated on, and of the other lung, were similar in the supine position. There was a significant (P less than 0.01) increase in ventilation and a decrease in end-tidal PCO2 of the upper lung after turning the patient on to the side. Simultaneously, the physiological deadspace fraction of tidal volume (VD/VT) increased from 42 to 45% (P less than 0.05). Mean pulmonary arterial pressure (MPAP) increased slightly as surgery on the chest wall commenced. A concomitant increase of carbon dioxide elimination from the upper lung occurred also, although the distribution of ventilation, between the lungs, was unchanged in comparison with the conditions during undisturbed anaesthesia. Individual changes in MPAP (delta MPAP) and corresponding changes in VD/VT (delta (VD/VT)) were negatively correlated (r = -0.68, P less than 0.01). The regression equation was delta (VD/VT) (%) = 0.7 - 0.83 X delta MPAP (mmHg). It was concluded that variations in pulmonary arterial pressure during surgical stimulation may significantly affect the pattern of carbon dioxide elimination in the lungs. However, there was no evidence that these effects were important clinically.
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| 35. |
- Werner, Olof, et al.
(author)
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Gas exchange and haemodynamics during thoracotomy
- 1984
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In: British Journal of Anaesthesia. - 1471-6771. ; 56:12, s. 1343-1350
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Journal article (peer-reviewed)abstract
- Cardiac index, systemic and pulmonary arterial pressures, carbon dioxide elimination and ventilation of each lung were studied during thoracotomy. Seventeen patients, placed in the full lateral position, were ventilated mechanically through a Carlens' tube to moderate hypocapnia. Mean cardiac index increased by 12% as the pleura was opened (P less than 0.05), with no further change during surgery on the still ventilated upper lung. Mean arterial pressure was unchanged after opening the pleura, but decreased from 114 +/- 15 mm Hg (mean +/- 1 SD) to 104 +/- 18 mm Hg during surgery on the lung (P less than 0.01). Mean pulmonary artery pressure was unchanged. There was a significant (P less than 0.01) increase in carbon dioxide elimination from the upper lung when the pleura was opened. In addition, the ventilation of this lung increased significantly (P less than 0.05). Mean end-tidal PCO2 of the lower lung increased from 4.1 to 4.2 kPa after opening the pleura, while that of the upper lung increased from 3.0 to 3.6 kPa (P less than 0.01). VD/VT decreased from 43 to 38% as the pleura was opened (P less than 0.01). During surgical handling of the lung, marked decreases in ventilation, compliance, carbon dioxide elimination and end-tidal PCO2 were observed in the upper lung. We conclude that ventilation-perfusion mismatch decreased on opening the pleura, and that neither opening the pleura nor the subsequent lung surgery (both lungs being ventilated) caused any clinically important derangements in haemodynamics or oxygenation.
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| 36. |
- Wikström, P M, et al.
(author)
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Non-autogenous control of ribosomal protein synthesis from the trmD operon in Escherichia coli
- 1988
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In: Journal of Molecular Biology. - : Elsevier BV. - 0022-2836 .- 1089-8638. ; 203:1, s. 141-152
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Journal article (peer-reviewed)abstract
- The trmD operon of Escherichia coli encodes the ribosomal proteins S16 and L19, the tRNA(m1G37)methyltransferase and a 21,000 Mr protein of unknown function. Here we demonstrate that, in contrast to the expression of other ribosomal protein operons, the amount of trmD operon mRNA and the rate of synthesis of the proteins encoded by the operon respond to increased gene dosage. The steady-state level of the mRNA was about 18 times higher, and the relative rate of synthesis of the ribosomal proteins S16 and L19, the tRNA(m1G37)methyltransferase and the 21,000 Mr protein was 15, 9, 25 and 23 times higher, respectively, in plasmid-containing cells than in plasmid-free cells. Overproduced tRNA(m1G37)methyltransferase and 21,000 Mr protein were as stable as E. coli total protein, whereas the two ribosomal proteins were degraded to a large extent. The steady-state amount of S16 and L19 in the plasmid-containing cells exceeded that in plasmid-free cells by threefold and twofold, respectively. No significant effect on the synthesis of the trmD operon proteins from the chromosomally located genes was observed when parts of the operon were expressed on different plasmids. Taken together, these results suggest that the expression of the trmD operon is not subject to transcriptional or translational feedback regulation, and demonstrate that not all ribosomal protein operons are regulated in the same manner. We propose that ribosomal protein operons that do not encode proteins that bind directly to rRNA are not under autogenous control. Metabolic regulation at the transcriptional level and protein degradation are plausible mechanisms for the control of expression of such operons.
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