Search Results - (Author, Cooperation:F. Grimm)

2015-06-18

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Alternative Splicing ; Animals ; Cardiomyopathy, Hypertrophic/genetics/*metabolism/pathology/physiopathology ; Disease Models, Animal ; Fructokinases/deficiency/genetics/*metabolism ; Fructose/*metabolism ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics/*metabolism ; Isoenzymes/deficiency/genetics/metabolism ; Male ; Metabolic Syndrome X/metabolism ; Mice ; Phosphoproteins/deficiency/genetics/*metabolism ; Ribonucleoprotein, U2 Small Nuclear/deficiency/genetics/*metabolism

0011-2240

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Medicine

Electronic Resource

0022-328X

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

0368-2048

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Physics

Electronic Resource

1432-2307

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource

1432-2307

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource

1432-1793

Springer Online Journal Archives 1860-2000

Biology

Abstract Nereis succinea (Frey and Leuckart, 1847), collected in 1987 from the Weser estuary, FRG, was exposed to different temperatures in the laboratory. Metamorphosis to heteronereid stages, as well as swarming at a minimum temperature of 12°C, was induced by raising temperatures around the time of the new moon. Lunar periodicity was illustrated under natural temperature-programs, and at 16°C. An abrupt increase in temperature caused swarming to occur at different times of the lunar cycle.

Electronic Resource

1871-4528

Virusnachweis ; Testsicherheit

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Summary Virus testing in basic breeding stocks could be rationalised if detection could be done with known mixtures of sera. A prerequisite for the use of mixed sera is that detection must be as reliable as it is with simple antisera. On each occasion the study was carried out on the pinnate leaves of 100 plants grown from eye plugs. Some were infected with one, others with more than one virus. Antisera and buffer systems from Fa. Boehringer, Mannheim were used. Mixed sera were prepared by mixing antisera in buffer, with all PLRV-containing mixtures being prepared in the buffer used in PLRV tests. A direct comparison between simple antiserum and mixed serum was made in each case and the reactions were assessed visually. The results were subjected to statistical analysis using the χ2 test with a two-way table. The mixed sera M/S (PVM antiserum+PVS antiserum) and A/Y (PVA antiserum+PVY antiserum) were tested in preliminary experiments and gave good overall agreement with the simple antisera. Photometric measurement (405 nm) for PVA gave a higher extinction value (0.45) with A/Y mixed serum than with A-antiserum alone (0.40). The same effect was observed in comparisons of A/Y and Y. A systematic comparison was made with PVA, PVM, PVS, PVX, PVY and PLRV using mixed sera and simple antisera. The results obtained with simple antisera were taken as correct and served as standards. The compositions of the various mixtures under test are given in column 1 of Tables 1–6. The percentage agreement between the results of simple and mixed sera (column 6) was calculated as the quotient of the sum of virus-positive and negative findings for simple sera (columns 4 and 5) and the sum of virus-positive and negative findings for simple sera (columns 2 and 3). In the worst case, i.e. the comparison of results obtained with A/X mixed serum and X anti-serum, the agreement was ca 92%. Statistical analyses of the results with the χ2 test gave % P values (d.f.=1) that were lowest for the Y/R mixture at 70–80. It follows that the results for mixed and simple antisera are basically the same and that observed variation is due to chance. Plants infected with one virus were diagnosed just as effectively with mixed sera as plants infected with more than one virus. Tests that were virus-positive gave a more intense colour with mixed than with simple antisera. An increasing number of components in the mixture (up to 6 in a combination) resulted in no deterioration in test sensitivity. The good agreement between the results obtained with mixed and simple antisera would permit the use of mixed sera for virus diagnoses in potato leaves. The high reliability of detection obtained with ELISA is maintained with mixed sera. This presumably applies also to untested combinations. However, quantitative virus determination is possible only with strong reservations, because the strength of the colour reaction increases with the use of mixed sera, even if only one virus is being determined. An important advantage of mixed sera is the cost saving incurred through reductions in the work effort and the quantities of serum used. The procedure may also be applicable to tubers but this has yet to be tested.

Résumé La rationalisation des tests virologiques dans la sélection conservatrice pourrait être réalisée avec l'utilisation d'un mélange de différents antisérums que nous appellerons antisérums mixtes. L'antisérum mixte ne peut être utilisé qu'à condition que le résultat soit comparable à celui obtènu avec les antisérums simples. Chaque test a été effectué sur des feuilles composées provenant de 100 plantules indexées. Les plantules étant contaminées par un ou plusieurs virus à la fois. Les antisérums et le tampon utilisés proviennent de Fa. Böhringer/Mannheim. Les antisérums mixtes sont obtenus après mélanges des différents antisérums simples dans le tampon. Tous les mélanges d'antisérums contenant le PLRV sont préparés avec le tampon destiné au test du PLRV. Les échantillons sont testés avec l'antisérum simple et l'antisérum mixte. L'évaluation des réactions est effectuée visuellement. Le test statistique du χ2 est appliqué selon le principe du tableau à 4 champs. Les antisérums mixtes M/S (antisérum PVM +antisérum PVS) et A/Y (antisérum PVA+ antisérum PVY) ont été examinés dans des tests préliminaires, leur concordance a été très bonne avec l'antisérum simple. Les résultats du photomètre (405 nm) ont donné des valeurs d'extinction supérieures avec les antisérums A/Y mélangés (0,45) qu'avec l'antisérum A seul (0,40). La même tendance a été observée lors de la comparaison des tests A/Y mixte et Y. Une comparaison systématique est effectuée entre les antisérums mixtes et simples pour les virus PVA, PVM, PVS, PVX, PVY et PLRV. Les résultats obtenus avec les antisérums simples ont servis de contrôle. La composition des antisérums mixtes testés figure dans la colonne 1 des tableaux 1–6. Le taux de correspondance entre antisérums simples et mixtes (colonne 9) correspond au quotient des sommes des valeurs positives et négatives des antisérums mixtes (col. 4 et 5) et la somme des valeurs positives et négatives obtenus avec des antisérums simples (col. 2 et 3). Dans le cas le plus défavorable, c'est-à-dire entre l'antisérum mixte A/X et l'antisérum simple X, le résultat du quotient atteint 92%. Dans tous les autres cas, les valeurs de comparaison des antisérums mixtes et simples, sont supérieurs. Le test du χ2 a donné les P% (d.l.=1). Les valeurs P sont les plus faibles avec le mélange Y/R, 70–80%. On peut ainsi conclure que les résultats entre sérums mixtes et simples sont comparables et les variations peuvent être considérées comme aléatoires. Le résultat du test avec antisérum mixte est tout aussi bon pour les plantes contaminées avec 1 virus que lorsqu'il y en a plusieurs. Les échantillons positifs réagissent d'une manière plus intensive avec un antisérum mixte qu'avec un antisérum simple. Le nombre croissant d'antisérums dans le mélange (jusqu'à 6) n'a pas modifié le résultat du test. Cette bonne concordance des résultats permet d'utiliser des antisérums mixtes pour le diagnostic viral des feuilles de pommes de terre. La sensibilité du test est maintenue avec l'utilisation d'antisérums mixtes. On peut admettre que les combinaisons qui n'ont pas été examinées se prêtent également bien pour le test. Lorsqu'il s'agit d'un test quantitatif du virus, il n'est alors pas indiqué d'utiliser les antisérums mixtes, en raison de la plus forte réaction (valeurs d'extinction plus élevées pour les antisérums mixtes) même lorsqu'un seul virus est détecté. Les antisérums mixtes permettent de faire des économies de temps et d'antisérums.

Zusammenfassung An Kartoffelblättern wurde die Testsicherheit von Mischseren mit der von Einfachantiseren verglichen. Gemischt wurden Antiseren gegen PVA, PVM, PVS, PVX, PVY und PLRV in Kombinationen von zwei bis sechs Antiseren. Das Blattmaterial wurde sowohl mit den Einfachantiseren als auch mit Mischseren getestet. Der Ergebnisvergleich zeigt, dass sich die Testsicherheit-bezogen auf die viruspositiven und virusnegativen Proben im Nachweis mit Einfachantiseren—bei Verwendung von Mischseren nicht ändert; statistisch gesicherte Abweichungen wurden nicht beobachtet. Mischseren eignen sich somit zum Nachweis von Kartoffelviren, wenn die Kenntnis der verursachenden Virusart nicht ausschlaggebend ist. Material- und Arbeitskosten können damit eingespart werden.

Electronic Resource

1871-4528

Bakteriennachweis ; ELISA ; Testsicherheit

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Summary Erwinia carotovora var.atroseptica (Eca) can survive for many years in tissue culture without signs of bacterial infection on the plants or of it being visible on the medium. Because the infection can be transmitted from one subcultivation to the next, there is a need for appropriate tests to detect latent contamination. Latent infection of in vitro plants, glasshouse plants and tubers by Eca was studied using ELISA and two nutrient media tests in trials to determine the levels of detection which could be achieved. Attempts were made to improve the interpretation of the ELISA results by comparing it with other methods of analysis. The plant material originated from in vitro material of known disease status. Sap samples for ELISA were pressed from whole in vitro plants, pieces from the stem bases of glasshouse plants and the heel-end of tubers. ELISA readings were taken at 405 nm using two photometers. The level used for discriminating between negative and positive results was based on calculating $$\bar x + 3s$$ (mean and spread of values respectively). YEB-medium in liquid form and the Luria-Bertani Medium in liquid and solidified (agar) form were the test media (Table 1). Finely cut nodal segments of in vitro plants were placed in liquid media and incubated for five weeks. In vitro leaves which had been pierced were laid on the agar medium. ELISA proved to be inadequate when the results from repeated subcultures were compared (Table 2). The reproducibility of the results varied in sign and value. Readings obtained with negative samples were in better agreement with the disease status of the plants than those from positive ones. Using calculated separation levels gave sharper differentiation in the results than using fixed values. The ELISA results, interpreted on the basis of $$\bar x + 3s$$ , varied considerably when applied to in vitro plants in the glasshouse (Fig. 1). Complete detection of the bacteria was only successful in the first test with in vitro plants and in tuber tests. Detection of latent Eca contamination was unsuccessful using the test nutrient media. Only 1 in 116 replicates gave the clouding expected with the nutrient media. There was strong growth of bacteria after two days in all tests with dilutions of pure cultures. False positives did not occur i.e. tests withErwinia-free clones remained clear. On the basis of these results a clear indication of latent Eca contamination on in vitro plants is not possible using ELISA, since the same clones gave positive or negative results depending on the time of testing. The poor reliability of the test must be due to the levels of the pathogen on in vitro plants (102/g), lower than the detection level of ELISA (103 cells ml−1). The failure of latent bacteria to grow in the test nutrient media may be due to the attachment of the Eca pathogen to the cell wall structure of the in vitro plants. For reliable detection an enzymatic pre-treatment is presumably necessary, which would allow the pathogen to grow actively in the test media. No improvement of detection levels can be expected using ELISA. Glasshouse grown plants give inconsistent results similar to in vitro cultures. The degree of detection achievable with tuber tests renders it impractical, since the danger of recontamination by Eca during tuber multiplication in the glasshouse is too great. However other approaches to detection described in the literature are either uncertain or too expensive, and it appears that there is no alternative to ELISA for the detection of latent Eca contamination. The possible danger of false results can be counteracted to some extent by the combined use of replication and evaluations based on calculated separation values.

Zusammenfassung Es wurde geprüft, mit welcher Nachweissicherheit in vitro-Klone auf latenten Befall vonErwinia carotovora var.atroseptica (Eca) untersucht werden können. Als Testmethoden wurden ELISA-daten von in vitro-Pflanzen, Topfpflanzen und Knollen sowie der Bakteriennachweis an in vitro-Proben auf Nährböden verglichen. Während die richtige Erfassung Eca-freier Klone mit allen Nachweismethoden fast fehlerfrei gelang, war die Ausgrenzung der positiven Proben mit ELISA teilweise nur mit unzureichender Testsicherheit möglich. Die Nährbodentests erwiesen sich als ungeeignet. Die besten Ergebnisse lieferte der ELISA-Knollentest, der aber wegen der Gefahr der Eca-Rekontamination ausscheidet. Aus Ermangelung rationeller Alternativen wird vorerst, trotz schwankender Nachweissicherheit, dem ELISA an in vitro-Pflanzen der Vorzug gegeben. Der Gefahr möglicher Fehlaussagen wird durch eine mehrfach gestaffelte Kombination von Wiederholungen und Verwendung eines Auswertungsverfahrens mit rechnerischer Grenzwertermittlung entgegengewirkt.

Electronic Resource

1572-9893

Springer Online Journal Archives 1860-2000

Geography

Abstract In this paper aspects of the regional differentiation within the German Democratic Republic are presented, and the structure, dynamics and development of this differentiation are shown. The GDR founded after World War II comprises a territory of 108,000 sq.km with 16.7 million inhabitants. At the initial stage, its territorial structure was marked by a polarization between the industrialized regions in the South and the backward agricultural regions of the North and the East. Under socialist condition, however, his regional differentiation has been changed during the last three decades due to various basic and sequent processes. The foundation and development of a nationally-owned sector, particularly in industry, and a cooperative sector in agriculture, the industrialization of former agrarian regions, demographic processes, and a changing settlement structure has contributed to this development. The present regional differentiation is analysed by a new probabilistic approach, and seven macro-regions of the GDR are described.

Electronic Resource

1434-6079

33.60.Cv ; 33.80.Eh

Springer Online Journal Archives 1860-2000

Physics

Abstract The general properties of the Cooper minimum in molecules are reviewed. Experimental results from synchrotron radiation together with theoretical calculations are presented on both the partial cross sections and angular distribution parameters, β. A detailed examination of HCl is used as an example. Previously unpublished results on CCl n H4−n , CCl n F4−n , ethylene dichloride, I2 and ICl are included. The Cooper minimum is largely discussed as a perturbation from atomic behavior, and is examined as a function of atomic number. The Cooper minimum is also examined as a function of chemical environment. Finally, needs for future research are briefly described.

Electronic Resource

1432-1955

Springer Online Journal Archives 1860-2000

Biology

Medicine

Abstract Different clones and subpopulations of clones ofLeishmania infantum were analyzed for their infective potential in vitro. Infectivity for macrophage-like cells (P388D1) and the response to a challenge with normal human serum enabled a clear differentiation between infective and non/low-infective populations. The results were confirmed by determination of parasite burdens in the spleens of infected golden hamsters. Long-term cultivation assays in vitro were used to test the influence of different cultivation conditions on the infectivity of promastigotes. An originally infective clone (LEM 768-A/ST) lost its infectivity during these assays but could regain it after the cultivation conditions had been changed. In addition, an originally non/low-infective clone (LEM 287-D/ST) could be forced to produce highly infective promastigotes. Infective cells were found only among stationary-phase promastigotes, i.e. after the cultures had reached a maximal number of cells per milliliter and the cell volume had clearly decreased.

Electronic Resource

1432-1955

Springer Online Journal Archives 1860-2000

Biology

Medicine

Abstract  Cases of leishmaniasis imported into Switzerland were diagnosed by culture and/or Giemsa-stained smears. The cultures proved to be positive in 61 of 64 confirmed cases, whereas only 49% of Giemsa-stained smears were positive. Promastigotes were detected on average after 3.6±2.2 days. A total of 33 different isolates were characterized by isoenzyme analysis and typed as Leishmania infantum (10 cases, mainly from Europe), L. chagasi (1 case, Central America), L. major (12 cases, mainly from Africa), L. braziliensis (7 cases, South and Central America), and L. tropica (1 case, Near East). Two isolates could not be clearly classified. Correlations between species and origin or between species and type of biopsy were as expected.

Electronic Resource

0075-4617

Chemistry ; Organic Chemistry

Wiley InterScience Backfile Collection 1832-2000

Chemistry and Pharmacology

Electronic Resource

0365-9496

Chemistry ; Inorganic Chemistry

Wiley InterScience Backfile Collection 1832-2000

Chemistry and Pharmacology

Electronic Resource

0365-9496

Chemistry ; Inorganic Chemistry

Wiley InterScience Backfile Collection 1832-2000

Chemistry and Pharmacology

Electronic Resource

0365-9496

Chemistry ; Inorganic Chemistry

Wiley InterScience Backfile Collection 1832-2000

Chemistry and Pharmacology

3 Tab.

Electronic Resource