Showing papers by "University of Copenhagen published in 1978"

Rapid method for distinction of gram-negative from gram-positive bacteria

Abstract: A rapid method for distinction between gram-negative and grampositive bacteria by means of a 3% solution of potassium hydroxide is tested on 71 gram-positive and 55 gram-negative bacterial strains. The method proved reliable with one exception only, a Bacillus macerans strain. That strain was definately gram-negative on staining. Other Bacillus strains were proved gram-positive by the test, even those being gram-negative on staining.

Implications of Sex Differences in the Prevalences of Antisocial Personality, Alcoholism, and Criminality for Familial Transmission

Abstract: • We describe three multifactorial models of disease transmission in which the prevalences of a disease differ in men and women. These models demonstrate explicitly how such sex differences may be caused by genetic factors, home environment, sociocultural, or other nonfamilial factors. Independent sets of family data about antisocial personality and alcoholism in the United States and criminality in Danish twins are analyzed according to these quantitative models. Relevant clinical and adoption data about these disorders are reviewed. The sex differences observed in the development of antisocial personality and of crime appear to be due to familial factors whereas the differences between male and female alcoholics are due to nonfamilial factors. The models and results are discussed in terms of their general implications for testing hypotheses about gender-related differences.

An investigation of the anion-exchange resin method for soil phosphate extraction

Abstract: The anion-exchange resin method for soil-phosphate extraction was investigated on 4 different soils under varying experimental conditions. The variables were: (a) the type of anion-exchange resin, (b) the anionic form of the resin, (c) the ratio between the amounts of resin, soil, and water, and (d) the time of shaking.

The Testes After Torsion

Abstract: Summary— In torsion of the testis a large proportion of testes saved by surgery develop secondary atrophy. External manual reduction may be used as a first treatment, but surgical fixation is mandatory before the patient leaves the hospital. Prophylactic fixation of the contralateral testis should always be performed as 30% of the patients will otherwise develop symptoms. The preventive operation causes no discomfort to the patient and no harm to the testis. The fertility of the torsion patients is reduced. Patients treated for unilateral testicular torsion seem to have bilateral testicular abnormality resulting in decreased spermatogenesis.

Heavy ion reactions

Abstract: Combining elastic and inelastic processes with transfer reactions, this two-part volume explores how these events affect heavy ion collisions. Special attention is given to processes involving the transfer of two nucleons, which are specific for probing pairing correlations in nuclei. This novel treatment provides, together with the description of surface vibration and rotations, a unified picture of heavy ion reactions in terms of the elementary modes of nuclear excitation. Heavy Ion Reactions is essential reading for beginning graduate students as well as experienced researchers.

Oxygen isotope palaeotemperatures from the Tertiary period in the North Sea area

Abstract: THE understanding of global temperature conditions during the Tertiary period has greatly increased in the past decade owing to the successful oxygen isotope investigations of the numerous deep sea cores now available. Little attention has been paid, however, to applying the method to material from shelf sea areas, where the temperature-induced 18O-record in carbonate shells are generally believed to be superimposed by 18O-variations in water composition and by postdepositional alterations. This is unfortunate, as oxygen isotope data from coastal areas provide the best way of comparing traditional palaeoclimatological methods with the oxygen isotope procedure. The present study, which deals with the oxygen isotope composition of shell material from the Tertiary North Sea area, was initiated to overcome this lack of data. Here the oxygen isotope results are interpreted as palaeotemperatures and the first isotopic palaeotemperature curve for the Tertiary period in NW Europe is given.

Converging projections from the mediodorsal thalamic nucleus and mesencephalic dopaminergic neurons to the neocortex in three species.

Abstract: Previous studies in the rat have shown that the neocortical dopaminergic afferents, originating in the mesencephalon, terminate in those areas of the frontal lobe which receive projections from the mediodorsal thalamic nucleus i.e., the prefrontal cortex. In order to clarify whether this overlap is accidental for the rat or a consistent feature of several species we have compared the projection areas of the ventral tegmental area and the mediodorsal thalamic nucleus in three species, rat, opossum and tree shrew, using HRP injections in combination with glyoxylic acid histofluorescence method. The results have shown, first, that the area innervated by the mediodorsal nucleus of the thalamus is localized in a different part of the frontal lobe in each species: dorsolateral in the opossum, anteromedial, polar and suprarhinal in the rat and frontopolar in the tree shrew. Secondly, this area alone in each species receives projections from the ventral tegmental area. Thirdly, this area alone receives a dense innervation in the deep cortical layers by fluorescent fibres probably containing dopamine. The neighbouring neocortical areas receive afferents neither from the mediodorsal nucleus of the thalamus nor from the ventral mesencephalic tegmentum; their catecholamine innervation is mainly confined to the superficial layers and appears to be of noradrenergic nature. Although the techniques used did not allow a precise determination of the borders of the two projection areas and, therefore, the exact degree of overlap, it appears that mesencephalic dopaminergic innervation is a characteristic feature of the prefrontal cortex in the mammalian brain.

Distribution of vasoactive intestinal polypeptide (VIP) in the porcine central nervous system.

Abstract: — A sensitive and specific radioimmunoassay for vasoactive intestinal polypeptide (VIP) has been used to determine the regional distribution of the peptide in the porcine CNS. The hippocampus and cerebral cortex contained the highest concentration of VIP, while lower but significant amounts were present in the hypothalamus and neurohypophysis. The immunoreactive VIP in the brain appeared to be identical with the octacosapeptide originally isolated from porcine small intestine, since it was found to have identical chromatographic properties. to dilute in parallel with the standard curves and to react equally with six different VIP antisera independent of extraction procedure used.

Standardization of allergen extracts with appropriate methods. The combined use of skin prick testing and radio-allergosorbent tests.

Abstract: This paper presents recommendations for standardization of allergen extract by the combined use of skin prick tests and radioallergosorbent tests. These tests provide appropriate means for quantitation of the total allergenic activity of an extract. Advantages and limitations are discussed with reference to the literature.

Kinetic characteristics of the glutamate uptake into normal astrocytes in cultures

Abstract: Kinetics for uptake and release of glutamate were measured in normal, i.e., nontransformed, astrocytes in cultures obtained from the dissociated, cortexenriched superficial parts of the brain hemispheres of newborn DBA mice. The uptake kinetics indicated a minor, unsaturable component together with an intense uptake following Michaelis-Menten kinetics. TheK m (50 μM) was reasonably comparable to the corresponding values in brain slices and in other glial preparations. TheV max (58.8 nmol min−1 mg−1 protein) was, however, much higher than that observed in glial cell lines or peripheral satellite cells, and also considerably higher than that generally reported for brain slices. The release of glutamate was much smaller than the uptake, and only little affected by an increase of the external glutamate concentration, suggesting a net accumulation of glutamate rather than a homoexchange. Such an intense accumulation of glutamate into normal astrocytes may play a major role in brain metabolism and may help keep the extracellular glutamate cohcentration below excitatory levels.

Computer-aided layout design

Abstract: Within the general problem area of location problems, the layout planning problem or facilities location problem has for years attracted the attention of building planners (architects, industrial engineers) and operations researchers.

The extracellular potassium concentration in brain cortex following ischemia in hypo- and hyperglycemic rats

Abstract: The extracellular potassium concentration, [K+]e, was measured in the brain cortex of hypo-, normo- and hyperglycemic rats following brain ischemia. The increase in [K+]e in control rats could be characterized by 3 phases: an initial slow rate of rise where the [K+]e rose in 2 min from 3 to 9 mM followed by an abrupt, steep increase to 60 mM within 10 s and finally a slow rise to 80 mM. In the hyper- and hypoglycemic rats the same pattern appeared, but there were significant differences in the time course. The duration of the initial phase was approximately doubled in the hyperglycemic and halved in the hypoglycemic group. The [K+]e at which the steep increase was elicited was 8--10 mM in all groups. It is concluded that the duration of the initial phase is dependent upon available stores of glucose in the brain.

Sensory action potentials and biopsy of the sural nerve in neuropathy

Abstract: In 167 consecutive patients with various types of neuropathy, the amplitude of the sensory potential and the maximum conduction velocity along the sural nerve were compared with conduction in other sensory nerves, and were related to structural changes revealed by nerve biopsy. Electrophysiological findings in the sural nerve were similar to those in the superficial peroneal and the median nerve, though the distal segment of the median nerve was normal in 20 per cent of the patients when it was abnormal in the sural nerve. Quantitation of histological findings was a more sensitive method than the electrophysiological study in that two-thirds of 33 patients with normal electrophysiology in the sural nerve showed mild loss of fibres or signs of remyelination in teased fibres. The amplitude of the sensory potential was grossly related to the number of large myelinated fibres (more than 7 micrometer in diameter). Considering the 95 nerves from which teased fibres were obtained, maximum conduction velocity was abnormal in half. In 18 of these nerves, slowing in conduction was due to axonal degeneration: the velocity was as to be expected from the diameter of the largest fibres in the biopsy ("proportionate slowing"). In 9 nerves slowing was severe and more marked than to be expected from loss of the largest fibres ("disproportionate slowing"); these nerves showed paranodal or segmental demyelination in more than 30 per cent of the fibres. In 16 nerves from patients with neuropathy of different aetiology neither loss of fibres nor demyelination could explain the moderate slowing. The cause of slowing in these nerves is unknown; other conditions are referred to in which slowing in conduction cannot be attributed to morphological changes. Finally, electrophysiological and histological findings are reported in some patients with neuropathy associated with malignant neoplasm, with rheumatoid arthritis, with polyarteritis nodosa, with acute intermittent porphyria and with cirrhosis of the liver.

Selective ablations within the prefrontal cortex of the rat and performance of delayed alternation

Abstract: Ablations of the pregenual area of the anteromedial prefrontal cortex produced a significantly larger impairment in delayed alternation than did removal of the supragenual area. Both ablations caused significant impairments as compared with lesions of the posteromedial cortex. Only one of four rats with ablations of the dorsal bank and lip of the anterior part of the rhinal sulcus was impaired. The results indicate than in the rat, as in the monkey and dog, one part of the prefrontal cortex is particularly involved in mediation of delayed alternation.

Host plant discrimination within cruciferae: feeding responses of four leaf beetles (coleoptera: chrysomelidae) to glucosinolates, cucurbitacins and cardenolides

Abstract: Feeding responses of four Chrysomelidae to six less acceptable plants and to compounds from them were investigated by means of leaf disc tests. Significant differences were found between responses of different species, and plants containing potent feeding inhibitors were always rejected Cucurbitacins are potent feeding inhibitors to Phyllotreta nemorum, and this species does not eat Iberis species containing these compounds. Cardenolides are potent feeding inhibitors to P undulata, P tetrastigma and Phaedon cochleartae, and these three species do not eat the cardenolide containing Cheiranthus and Erysimum Six different glucosinolates all proved to be stimulatory when applied to pea leaf discs. Although the glucosinolates differed somewhat in their ability to stimulate feeding, no correlation is found between content of glucosinolates and acceptability of the investigated plants. Application of sinigrin to Iberis and Cheiranthus did not improve their acceptability The presence of glucosinolates is necessary for feeding to occur, but it is less important which glucosinolates are present. Cardenolides and cucurbitacins are suggested to be a second generation of protective compounds in Cruciferae, glucosinolates being the first ZUSAMMENFASSUNG UNTERSCHEIDUNG VON WIRTSPFLANZEN INNERHALB DER CRUCIFEREN: FRASSREAKTION VON VIER BLATTKAFERN (COLEOPTERA: CHRYSOMELIDAE) AUF GLUCOSINOLATE, CUCURBITACINE UND CARDENOLIDE Der Einfluss einiger sekundarer Pflanzenstoffe aus Cruciferen auf die Futteraufnahme von vier Chrysomeliden, die auf dieser Pflanzenfamilie vorkommen, wurde mittels Blattscheiben-Tests untersucht. Cucurbitacine sind starke Frasshemmstoffe fur Phyllotreta nemorum, weniger starke Hemmstoffe fur P. undulata und schwache Hemmstoffe fur P. tetrastigma und Phaedon cochleariae. Iberis-Arten, die Cucurbitacine enthalten, werden von P. nemorum und P. undulata abgelehnt, von den beiden anderen Arten aber akzeptiert. Cardenolid-Glykoside vom Strophanthidin-Typ sind starke Frasshemmstoffe fur P. undulata, P. tetrastigma und Phaedon cochleariae. Diese Arten lehnen Cheiranthus-und Erysimum-Arten, die solche Stoffe enthalten, ab. Die Futteraufnahme von P nemorum wird von diesen Stoffen nicht beeinflusst; P nemorum akzeptiert Cheiranthus- und Erysimum-Arten. Futteraufnahme fand bei Abwesenheit von Senfolglukosiden nicht statt. Sechs verschiedene Senfolglukoside waren alle imstande, das Aufnehmen von Erbsen-Blattscheiben zu stimulieren. Gewisse Unterschiede in der stimulierenden Wirkung der einzelnen Glukoside wurden gefunden. Das Vorkommen bestimmter Glukoside und die Akzeptabilitat der Pflanzen zeigten aber keine Korrelation. Anwesenheit oder Abwesenheit von Frasshemmstoffen beeinflusst die Akzeptabilitat der Pflanzenarten mehr als die Anwesenheit bestimmter Senfolglukoside. Wenn Senfolglukoside als eine erste Generation von Abwehrstoffen in Cruciferen aufgefasst werden, konnen Cucurbitacine in Iberis und Cardenolid-Glykoside in Cheiranthus und Erysimum als eine zweite betrachtet werden.