Showing papers by "Uppsala University published in 1981"
TL;DR: It is believed that P9A and P9B play an important part in the humoral immune responses described previously and that the P9 proteins represent a new class of antibacterial agents for which the name cecropins is proposed.
Abstract: Immune responses have been described for many different insect species. However, it is generally acknowledged that immune systems must therefore differ from those of vertebrates. An effective humoral immune response has been found in pupae of the cecropia moth, Hyalophora cecropia. The expression of this multicomponent system requires de novo synthesis of RNA and proteins and its broad antibacterial activity is due to at least three independent mechanisms, the most well known of which is the insect lysozyme. However, this enzyme is bactericidal for only a limited number of Gram-positive bacteria. WE recently purified and characterized P9A and P9B, which are two small, basic proteins with potent antibacterial activity against Escherichia coli and several other Gram-negative bacteria. We believe that P9A and P9B plays an important part in the humoral immune responses described previously and that the P9 proteins represent a new class of antibacterial agents for which we propose the name cecropins. We describe here the primary structures of cecropins A and B. We also show that cecropin A is specific for bacteria in contrast to melittin, the main lytic component in bee venom which lyses both bacteria and eukaryotic cells.
1,310 citations
TL;DR: The fasciocutaneous flap is very useful in the repair of soft tissue defects on the lower leg because of the good circulation and the surgical technique is described.
663 citations
TL;DR: It is shown that H 149/94 inhibits (H+ + K+)ATPase, which may explain its inhibitory action on acid secretion in vitro and in vivo and may be a highly selective clinical means of suppressing the acid secretory process.
Abstract: Studies both in vivo and in vitro have shown that substituted benzimidazoles inhibit the stimulation of acid secretion produced by dibutyryl cyclic AMP and histamine. Furthermore, the results differ from those produced by H2 antagonists and anticholinergic agents in that the inhibition is not competitive, and the site of action is intracellular and peripheral to that of dibutyryl cyclic AMP. To investigate the biochemical mechanism of action of substituted benzimidazoles, one such compound, H 149/94 (2-([2-(3-methyl)pyridyl-methyl]-sulphinyl)-5-methoxycarbonyl-6-methylbenzimidazol), has been tested either directly on an (H+ + K+)ATPase isolated from pig and human gastric mucosa or on the function of this enzyme in gastric glands isolated from rabbit and human gastric mucosa. (H+ + K+)ATPase, which has only been found at the secretory surface of the parietal cell, catalyses a one-to-one exchange of protons and potassium ions. It is possibly the proton pump within the gastric mucosa, and may thus be the terminal or one of the terminal steps of the acid secretory process. We show here that H 149/94 inhibits (H+ + K+)ATPase, which may explain its inhibitory action on acid secretion in vitro and in vivo. Because of the unique distribution and properties of the (H+ + K+)ATPase, the inhibitory action of H 149/94 on this enzyme may be a highly selective clinical means of suppressing the acid secretory process.
613 citations
TL;DR: Although there were many common properties of the lines, each line had a unique profile of the parameters evaluated and most likely reflects the individuality of the tumors of origin and individual genotypes and capacity for a range of phenotypic expression of the cells.
Abstract: Six new permanent cell lines were established from human gliomas and compared to nine other cell lines from human gliomas. All fifteen lines had individually distinct HLA phenotypes and all but two, which were from a black patient, had type B glucose-6-phosphate-de;hydrogenase isoenzymes. Morphologically, the lines could be classified into four patterns descriptively designated as fibroblastic, fascicular, epithelial, or glial. Four of the lines grew progressively and could be serially transplanted when injected into athymic mice; two others grew initially and then regressed. From none to 100% of cells developed elongated tapering processes and showed reduction in nuclear-cytoplasmic ratio in the presence of 1 mM cyclic AMP and theophylline. Levels of 2'-3' cyclic nucleotide 3'-phosphohydrolase activity ranged from nondetectable to 12.78 +/- 1.49 micromoles 2' AMP formed per hr mgm total protein. None of the lines had detectable S-100 protein, but two had readily demonstrable glial fibrillary acidic protein in indirect immunofluorescence. Fibronectin levels in spent culture supernatants ranged from undetectable levels to 21.4 micrograms/ml/10(5) cells. All but one line shared surface antigens with normal human adult or fetal brain, as detected in absorption analyses with nonhuman primate antiserum raised against glioblastoma multiforme tissue or cell line U-251 MG. Although there were many common properties of the lines, each line had a unique profile of the parameters evaluated. This heterogeneity most likely reflects the individuality of the tumors of origin and individual genotypes and capacity for a range of phenotypic expression of cells.
484 citations
TL;DR: This ‘salting out’ method was applied to enterotoxigenic Escherichia coli strains with different surface protein antigens, found to have a surface hydrophobicity in the following order: CFA/I >CFA/II > K88∼K99 > type 1.
423 citations
TL;DR: The results support the hypothesis that greater effects are achieved when the method used fits the patient's response pattern than when it does not, and show that both exposure and applied relaxation were significantly better than the waiting-list condition.
341 citations
TL;DR: It was found that both drugs reduce the number of intromissions preceding ejaculation and shorten the ejaculation latency and sexual behavior was partly or completely restored in castrated male rats after injection with 8-OMe- DPAT or 8-OH-DPAT.
Abstract: 8-Methoxy-2-(di-n-propylamino) tetralin (8-OMe-DPAT) and 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) are two new drugs exerting selective actions on brain 5-HT neurotransmission. In the present experiments we have investigated the effects of these two drugs on male rat sexual behavior. It was found that both drugs reduce the number of intromissions preceding ejaculation and shorten the ejaculation latency. These effects are extremely pronounced and several animals ejaculate at the first intromission. In addition 8-OH-DPAT produced a slight reduction of the post-ejaculatory interval. There were no significant effects on latency to initiate copulation or in the number of mounts preceding ejaculation. Finally, sexual behavior was partly or completely restored in castrated male rats after injection with 8-OMe-DPAT or 8-OH-DPAT.
318 citations
TL;DR: The results demonstrate that the effects of Capsaicin are not confined to substance P immunoreactive primary sensory neurons, and the possibility is discussed that capsaicin effects specifically functioning rather than chemically specific primary sensory cells.
Abstract: After neonatal treatment of rats with capsaicin, the spinal cord, the spinal trigeminal nucleus and spinal and trigeminal ganglia were analysed with immunohistochemistry using antisera to several peptides and 5-hydroxytryptamine. A marked decrease was observed in substance P-, cholecystokinin-, somatostatin- and VIP-like immunoreactivity present in the central branches of primary sensory neurons in the spinal cord and in substance P- and somatostatin-like immunoreactivity in sensory ganglion cells. No definite depleting effect of capsaicin could be established on 5-hydroxytryptamine and peptides, such as enkephalin and neurotensin, present in centrally originating fibres in the dorsal horn of the spinal cord. The results demonstrate that the effects of capsaicin are not confined to substance P immunoreactive primary sensory neurons. The possibility is discussed that capsaicin effects specifically functioning rather than chemically specific primary sensory neurons.
304 citations
TL;DR: There was no clearcut relationship between the ways of acquisition and anxiety components (subjective, behavioral, physiological), nor did the conditioning and indirectly acquired phobias differ in severity, but some interesting trends emerged in the data, showing that animal phobics who recalled conditioning experiences to a larger extent also responded physiologically.
287 citations
TL;DR: Human neuroblastoma cells treated by 12‐O‐tetradecanoyl‐phorbol‐13‐acetate (TPA) express morphological and biochemical changes, which indicate that differentiation towards more mature cells has occurred.
Abstract: SK-N-SH and SH-SY5Y human neuroblastoma cells treated by 12-)-tetradecanoyl-phorbol-13-acetate(TPA) express morphological and biochemical changes, which indicate that differentiation towards more mature cells has occurred. The most prominent morphological changes were the development in 40-60% of the cells of cell-surface projections longer than 50 micrometers and cytoplasmic neurosecretory granules demonstrated by electron microscopy. At the biochemical level, TPA induced a two-fold increase in the relative activity of neuron-specific enolase and 30- to 40-fold increase in noradrenaline and adrenaline concentrations. A decrease in proliferation rate of TPA-treated cells was observed. The biological effects of TPA were slightly potentiated by nerve growth factor.
272 citations
TL;DR: Felodipine is a new antihypertensive agent which seems specifically to dilate precapillary resistance vessels in vivo and is a structural analogue of nifedipine1 and SKF 242602, implying that their vascular as well as myocardial actions are due to a blockade of Ca2+ influx.
Abstract: Despite the marked differences in their chemical structure, members of a heterogeneous group of pharmacological agents are thought specifically to block Ca2+ influx through calcium channels1 and thus mediate negative inotropic cardiac effects and vasodilatation. Electrophysiological studies of the myocardium have shown that the slow inward Ca2+ current is blocked1, but the cellular mechanism of these agents in vascular smooth muscle is largely unknown. Felodipine [4-(2,3-dichlorophenyl)-1,4-dihydropyridine-2,6-dimethyl 3,5-dicarboxylic 3-ethylester and 5-methylester)] is a new antihypertensive agent which seems specifically to dilate precapillary resistance vessels in vivo. It is a structural analogue of nifedipine1 and SKF 242602, both of which have been classified as ‘calcium antagonists’, implying that their vascular as well as myocardial actions are due to a blockade of Ca2+ influx. However, the findings reported here point rather to an interaction between felodipine and calcium-binding proteins such as calmodulin.
TL;DR: In this paper, a new method is proposed for a simultaneous factor analysis of dichotomous responses from several groups of individuals, making it possible to compare factor loading pattern, factor variances and covariances, and factor means over groups.
Abstract: A new method is proposed for a simultaneous factor analysis of dichotomous responses from several groups of individuals The method makes it possible to compare factor loading pattern, factor variances and covariances, and factor means over groups The method uses information from first and second order proportions and estimates the model by generalized least-squares Hypotheses regarding different degrees of invariance over groups may be evaluated by a large-sample chi-square test
TL;DR: It is suggested that the cell-binding sites in collagen have a simple structure and occur in multiple copies along the collagen molecule, indicating different affinities of the cells for these substrates.
TL;DR: In the paper some different ways to identify systems from noisy data are discussed and sufficient conditions for identifiability are given.
TL;DR: The results indicate that acute arterial hypertension tends to cause forced and long-lasting vasodilation in some areas in the brain but regions which are resistant to the acute rise have an increase in the vascular tone.
Abstract: The cervical sympathetic chain was stimulated electrically at 6 or 3 Hz on one side in anesthetized cats. Acute arterial hypertension was induced by ligation of the aorta. Evans blue was given as tracer for protein leakage. The regional blood flow in the brain was determined by using labelled microspheres. At high blood pressures there was a multifocal breakdown of the blood-brain barrier. The regions with breakdown had 10-20 times the normal flow rates. With a maintained hypertension regions which were overperfused at 5 min were still overperfused at 10 min, but there was little addition of new overperfused areas. Normalization of the pressure resulted in almost twice the normal flow rates in previously overperfused regions. The breakdown of the blood-brain barrier was restricted to the non-stimulated side, or more marked on that side. The protective effect of the sympathetic stimulation lasted more than 10 min. The results indicate that acute arterial hypertension tends to cause forced and long-lasting vasodilation in some areas in the brain but regions which are resistant to the acute rise have an increase in the vascular tone. Sympathetic activity helps in developing this tone. Normalization of the blood pressure results in partial recovery of the vascular tone in previously overperfused regions and normalization in other areas.
TL;DR: Two species of crayfish, Astacus astacus and Pacifastacus leniusculus could recognize components from fungal cell walls, i.e. β-1,3-glucans, since a clotting process and subsequent protein (phenoloxidase) attachment to many foreign surfaces were induced by these β-2,2- glucans.
Abstract: Two species of crayfish, Astacus astacus and Pacifastacus leniusculus could recognize components from fungal cell walls, i.e. β-1,3-glucans, since a clotting process and subsequent protein (phenoloxidase) attachment to many foreign surfaces were induced by these β-1,3-glucans. The process of clotting and phenoloxidase attachment was dependent on Ca2+. The biochemical mechanism of β-1,3-glucan induction of phenoloxidase attachment is not fully understood, although preliminary observations indicate that the glucans activated a serine protease, which then induced phenoloxidase attachment.
TL;DR: Six criteria suitable for measures of ecological coexistence are proposed and three of them, suggested by Ochiai, Dice and Jaccard are recommended.
Abstract: Six criteria suitable for measures of ecological coexistence are proposed. For twenty such measures are examined whether they satisfy these criteria or not. Four of them satisfy all six criteria. Three of them, suggested by Ochiai, Dice and Jaccard are recommended. For them asymptotic standard errors are given. An example is given with asymptotic confidence intervals for the three measures recommended.
TL;DR: The findings support the view that susceptibility to NK-cell mediated lysis may vary according to the stage of differentiation of the target cell, and that, in vivo, both normal and malignant cells are under surveillance by NK cells.
Abstract: Natural killer (NK) cells have unique surface features and physiological characteristics and a selective ability to lyse some, but not other, target cells1,2. However, the basis of this selectivity remains obscure at both effector and target cell levels. Proposed specific NK-cell target moieties3–5 include glycolipids, and glycoproteins unrelated to the major histocompatibility complex, while malignant and certain normal cells have been found to be susceptible to NK-cell-mediated cytolysis6–8. There is good evidence that NK cells can inhibit the outgrowth of small numbers of transplanted tumour cells in vivo9,10 and can restrict the establishment of secondary metastasis11,12. It has thus been speculated that NK cells function as a primitive, thymus-independent immune system using phylogenetically preserved target structures to form a cell-mediated resistance barrier against the outgrowth of certain tumour cells1. The presence in the thymuses of neonatal mice and humans8,13 and in the marrow of human fetuses, of apparently normal cells which are quite sensitive to NK cells suggested that NK cells might have an increased ability to cause the lysis of cells at a particular stage of their differentiation. In agreement with this concept, embryonal carcinoma cells at various stages of differentiation display a strikingly different susceptibility to NK-cell-induced lysis14. Here only cell types representing early stages were sensitive to NK-cell-mediated cytolysis, whereas the more differentiated endodermal cell lines showed close to complete resistance. The above data would thus support the view that, in vivo, depending on the stage of differentiation, both normal and malignant cells are under surveillance by NK cells. Here we have considered the question of differentiation-related NK-cell susceptibility using defined cell lines known to undergo controlled differentiation in the presence of various agents. Three tumour cell-lines were investigated, and all demonstrated a striking positive correlation between a decrease in NK-cell susceptibility and the induction of differentiation by the various inducers. Our findings support the view that susceptibility to NK-cell mediated lysis may vary according to the stage of differentiation of the target cell.
TL;DR: The chapter discusses an experimental model in which intracellular organelles are introduced into the lysosomal apparatus of Kupffer cells by means of heterophagy, and the study of the heterophagic model has advantages over induced autophagy because the degradation of each membrane constituent or cell organelle can be separately studied.
Abstract: Publisher Summary This chapter describes the mechanisms of intralysosomal degradation with a special reference to autophagocytosis and heterophagocytosis of cell organelles. Autophagy is the process of sequestration of intracellular components and their subsequent degradation by the lysosomes. The process of degradation is of fundamental importance in cell function because under steady-state conditions subcellular components are broken down and resynthesized many times during the life span of the cells. Autophagy contributes to the turnover of cell constituents during physiological cell conditions. Autophagy is induced by numerous treatments, conditions, or agents that cause cell dysfunction. Biological components from the extracellular space can also enter the lysosomal compartment and become degraded through the process of heterophagy. The chapter discusses an experimental model in which intracellular organelles are introduced into the lysosomal apparatus of Kupffer cells by means of heterophagy. The study of the heterophagic model has advantages over induced autophagy because the degradation of each membrane constituent or cell organelle can be separately studied. The heterophagy model is also useful to evaluate the capacity of lysosomes to degrade various membrane components in vivo .
TL;DR: The investigation includes methods for open loop operation as well as methods designed for closed loop operation, and studied how the use of filters will influence the covariance matrix of the parameter estimates.
TL;DR: In this article, a reversed-phase system has been developed that permits the detection and quantification of down to 0.1 nmole of non-UV-absorbing cations and anions using a UV detector.
TL;DR: In this paper, the convergence and accuracy properties of the Steiglitz and McBride identification method are examined for a sufficiently large number of data points and it is shown that the method can converge to the true parameters only when the additive output noise is white.
Abstract: The convergence and accuracy properties of the Steiglitz and McBride identification method are examined. The analysis is valid for a sufficiently large number of data. It is shown that the method can converge to the true parameter vector only when the additive output noise is white. In that case the method is proved to be locally convergent to the true parameters. The global convergence properties are also investigated. It is pointed out that the method is not always globally convergent. Some sufficient conditions guaranteeing global convergence are given. Assuming convergence takes place the estimates are shown to be asymptotically Gaussian distributed. An explicit expression is given for their asymptotic covariance matrix.
TL;DR: The major late adenovirus promoter is active early after infection, selectively producing messenger RNAs coding for polypeptides with molecular weights of 55, 52K mRNAs, suggesting that a differential splicing pattern occurs at the transition from early to late viral gene expression.
Abstract: The major late adenovirus promoter is active early after infection, selectively producing messenger RNAs coding for polypeptides with molecular weights of 55,000, 52,000 and 14,000. This selective expression suggests that a differential splicing pattern occurs at the transition from early to late viral gene expression. Activation of the late promoter and splicing of the 55, 52K mRNAs does not require newly synthesized virus polypeptides.
TL;DR: Purified eosinophil and neutrophil cationic proteins isolated from the lysosomal secretion granules of human granulocytes, evoke characteristic, dose‐dependent morphological changes in young schistosomula of S. mansoni both in vitro and in viva.
Abstract: SUMMARY
Purified eosinophil and neutrophil cationic proteins isolated from the lysosomal secretion granules of human granulocytes, evoke characteristic, dose-dependent morphological changes in young schistosomula of S. mansoni. The first sign of damage is seen within 15–30 min of incubation and involves the formation of surface microvilli and blebs. Subsequently, tegumental evaginations of varying size are developed, but these appear to explode with rapidity, so that lengths of expanded tegumental outer membrane are deposited over the severely damaged surface of the parasite. Both types of granulocyte proteins are able to effect comparable damage at equimolar concentration. Other cationic proteins such as protamine and poly-L-arginine also damage the parasite surface but the pathological changes differ from those induced by the granulocyte proteins and they take longer to develop. In contrast, lysozyme-treated parasites are virtually similar to control schistosomula incubated in medium alone. These findings are discussed in relation to published data concerning the interaction of intact granulocytes with young schistosomula both in vitro and in viva.
TL;DR: In this paper, the in-phase and out-of-phase properties of a spin glass were investigated and it was shown that the properties of spin glass have a broad spectrum of relaxation times.
01 Oct 1981
TL;DR: In this article, a Fourier transform pulsed-gradient spin-echo 1H and 13C NMR method was employed to obtain multicomponent self-diffusion data for seven microemulsion systems.
Abstract: A novel Fourier transform pulsed-gradient spin-echo 1H and 13C NMR method was employed to obtain multicomponent self-diffusion data for seven microemulsion systems. These included ionic surfactant-cosurfactant (short- or long-chain alcohol)-hydrocarbon-water, nonionic surfactant-hydrocarbon-water, and ionic surfactant (of the swelling type)-hydrocarbon-water systems. For the short-chain alcohol (butanol or pentanol) systems both water, hydrocarbon, and alcohol self-diffusion are very rapid over wide concentration regions. In contrast to micellar solutions and certain liquid crystalline phases there is apparently no marked separation into hydrophobic and hydrophilic domains; this is considered to be due to the alcohol having a compatibility with both aqueous and hydrocarbon environments as well as internal interfaces. There appear to be no extended well-defined structures in these systems. Instead the microemulsions are argued to have very flexible and low-order internal interfaces which open up and reform at a short time scale. It seems reasonable to assume a polydispersity in aggregate size and shape and it appears to be a clear possibility that there are mainly quite small aggregates. The nonionic surfactant system shows strong resemblances to the short-chain alcohol system while the remaining systems (long-chain alcohol or absence of alcohol) show a more pronounced separation into hydrophobic and hydrophilic regions.
TL;DR: By using this method, microspheres, injected for studies of the capillary blood flow, can be readily located and counted in both the islets and the exocrine parenchyma.
Abstract: A technique is described for visualization of the pancreatic islets in the rat by simple dark field illumination of pieces of the frozen and thawed pancreas. By using this method, microspheres, injected for studies of the capillary blood flow, can be readily located and counted in both the islets and the exocrine parenchyma. The procedure could be useful both for rapid estimations of the total number of islets and for studies of their microcirculation.
TL;DR: Patients with increased, thyroid‐stimulating‐hormone (TSH) concentrations in the serum while fasting were studied before and after substitution with l‐thyroxine and TSH normalized as did also the response to a load with thyroid‐releasing hormone (TRH).
Abstract: . Twenty-one patients with increased, thyroid-stimulating-hormone (TSH) concentrations in the serum while fasting were studied before and after substitution with l-thyroxine. Nine patients had TSH values 40 mU/1 had an average serum-thyroxine value of 23 nmol/1. On treatment TSH and thyroxine normalized (reference limits < 8 mU/1 and 65–160 nmol/1 respectively) as did also the response to a load with thyroid-releasing hormone (TRH).
In the group with severe thyroid dysfunction (TSH > 40 mU/1) the lipoprotein-lipase activities in both adipose and skeletal-muscle tissue were subnormal before therapy and increased during substitution treatment. This was also reflected in a significant increase of the post-heparin, lipoprotein-lipase activity in the plasma and of the fractional removal rate of an i.v. injected fat emulsion. Ten out of twelve patients showed a decrease of the triglyceride concentration in whole serum, which reflected changes of the triglyceride concentrations in low-density lipoproteins (LDL) and high-density lipoproteins (HDL) more than changes in very-low-density lipoproteins, in which the triglyceride concentration was unchanged during treatment. In LDL, both the cholesterol and triglyceride concentrations were elevated before therapy and decreased by 22% and 32% of the pretreatment values, respectively, during treatment. Furthermore, the serum-apolipoprotein-B concentration decreased by 16%. The serum-apolipoprotein-A-I concentration was subnormal before treatment and the lipid composition of the HDL particle was changed towards an enrichment of triglycerides. During treatment, the HDL-triglyceride concentration decreased, whereas that of HDL cholesterol was unchanged. The fasting serum-insulin concentration increased significantly during the treatment period.
In the group with mild hypothyroidism (TSH < 40 mU/1), there were no significant changes similar to those found in severe hypothyroidism.
TL;DR: In this paper, the environmental isotope oxygen-18 was used as a tracer to separate stream discharge into flows originating from groundwater and fresh meltwater, and two watersheds in southern Sweden were studied during snowmelt 1979.
Abstract: The environmental isotope oxygen-18 was used as a tracer to separate stream discharge into flows originating from groundwater and fresh meltwater. Two, mainly forested, watersheds (areas 6.6 and 4.0 km2) in southern Sweden were studied during snowmelt 1979. The seasonal variation of δ18O in precipitation makes the δ18O of meltwater different from that of groundwater, hence making the separation possible.
The major part of the streamflow this spring originated from groundwater. Of the total water volumes that left the areas, during the two periods of snowmelt that occurred this year, the fraction of groundwater ranged between 0.7 ± 0.2 and 0.9(±) 0.2 The volume of meltwater in the streams corresponded to the volume of snowmelt and precipitation over 10-15% of the catchments. A field survey indicated that these percentages reasonably well describe the extension of the saturated areas, i.e. the effluent areas for groundwater where no infiltration can take place.
TL;DR: A high-performance liquid chromatographic method for the separation of optical isomers (enantiomers) of amines is described, based on ion-pair chromatography with a chiral counter ion in a system with an organic mobile phase and an adsorbing stationary phase.