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The growth forms of bi‐ and pluriennial central European plant species were analyzed and summarized systematically by means of a dichotomous key. Ten growth forms are distinguished according to vegetative morphological characters of the plants: holoparasitic erosulate, (simple) erosulate, floating semirosette, succulent semirosette, tufted semirosette, (simple) semirosette, storage root semirosette, tuber semirosette, storage root rosette, and (simple) rosette bi‐ or pluriennial plants. Only very few species are strictly biennial or pluriennial. Each individual plant can be assigned to only one growth form system according to the life span (the system of bi‐and pluriennials in the present case). However, several species include individuals that behave as annuals as well as biennials/pluriennials and/or periennials. The term “hapaxanthic” is discussed concerning to its reference level in relation to the plant organism. Three types of hapaxanthy can be distinguished in this context: Genet hapaxanthy with and without vegetative reproduction and ramet hapaxanthy.

The investigation of the vegetative characters of annual species from central Europe showed a hitherto not regarded large spectrum of 20 growth forms within this plant group. These growth forms can be identified by means of a dichotomous key. This is also a new method to present growth form systems. Although several surveys about growth forms have been carried out, the proposed systems are either incomplete or not consequent in the use of their classifying criteria. Moreover, annual species have never been investigated systematically according to their growth forms. Important characters which were used to characterize growth forms are the occurrence of a rosette, the presence or absence of supporting tissue which causes aerostability or aerolability, succulence, growth direction (plagiotropous, orthotropous) and metamorphoses (for scrambling). According to the mode of surviving the resting period, annuals can be grouped into therophytes, hydrophytes, and hemicryptophytes. Whereas therophytic and hydrophytic annuals perennate the winter exclusively as generative diaspores (seeds, spores), hemicryptophytic species survive as seedlings or young plants.

In this paper, we deal with the development of a support system for vehicle handling based on a traffic sign recognition system. This pattern recognition system consists of three modules dedicated to detection, recognition, and knowledge-based control. Neural networks are used as adaptive classifiers. The stage of development and the applicability of such a system are discussed.

The authors review the recent literature, including their own approaches, of stable isotope techniques applied to determining environmental effects on the health of children. The techniques involve the measurement of variations in natural isotope abundances of some elements with environmental significance, the use of enriched stable isotopes for in vivo and in situ tracer studies, in vitro isotope dilution techniques, and organ function tests using stable isotope-labelled compounds. These techniques are non-invasive and can be expected to contribute new insights into the behavior of different pollutants and their effect on children's health. Some of the techniques have been used in clinical research and diagnosis but their adaptation for investigations of clinically healthy children exposed to environmental pollution is desirable. Currently, as one of the specific aims of the Lepizig group of Human Exposure Research, the experience in biochemical and clinical isotope applications is being adapted to the environmental challenges in the heavily polluted industrial regions of Saxony.

During tow pH-induced fusion of influenza virus with erythrocytes we have observed differential dispersion of viral lipid and haemagglutinin (HA) into the erythrocyte membrane, and viral RNA into the erythrocyte using fluorescence video microscopy. The movement of both viral lipid and HA from virus to cell was restricted during the initial stages of fusion relative to free diffusion. This indicates the existence of relatively long-lived barriers to diffusion subsequent to fusion pore formation. Fluorescence anisotropy of phospholipid analogues incorporated into the viral membrane decreased when the pH was lowered to levels required for optimum fusion. This indicates that the restricted motion of viral membrane components was not due to rigidification of membrane lipids. The movement of HA from the fusion site was also assessed by photosensitized labelling by means of a fluorescent substrate (NBD-taurine) passing through the band 3 sialoglycoprotein (the erythrocyte anion transporter). We also examined the flow of lipid and aqueous markers during fusion of HA-expressing cells with labelled erythrocytes. During this cell-cell fusion, movement of lipid between fusing membranes begins before the fusion pore is wide enough to allow diffusion of aqueous molecules (Mr>500). The data indicate that HA is capable of creating domains in the membrane and controlling continuity of aqueous compartments which are bounded by such domains.

Beta vulgariss.l. is a morphologically variable taxon, that has transitional growth types between strictly orthotropous and plagiotropous growth. The development of a “secondary branching system” at the end of the growing season in taxa that are summer annual (under the climatic conditions of Central Germany) leads to perennial taxa that form slender storage roots and overwinter as rosettes. The shoots of the four morphologically different annual taxa are very similar anatomically. Collenchymatous ridges, that are conspicuous macroscopically as stem ridges, are typical. The secondary growth is anomalous and often irregular. Six more or less complete rings of connective and vascular tissue are formed in the roots by successively arising cambia, which have an unlimited ability to divide. However, the diameter of the roots does not only enlarge by divisions within the cambia but also by primary growth within the connective tissue.

Folgende Untersuchungen an Rattenorganen waren durch 15N-NMR-Messungen moglich:- Verteilung von in vivo applizierten 15N-markierten Verbindungen auf verschiedene Organe in Abhangigkeit von der Einwirkungszeit;- Ermittlung der Biotransformationskinetik von [15N]Glycin als Maβ fur die fortdauernde metabolische Aktivitat der entnommenen Leber;- Nachweis intermediar auftretender Metabolite des Glycins.Es wurden [15N2]Harnstoff und [15N]Glycin injiziert. Aus den Ergebnissen folgt, daβ die 15N-NMR-Spektroskopie in Verbindung mit der traditionellen 15N-Analyse eine neue Moglichkeit zur Verfolgung des Stickstoffstoffwechscls von Pflanze, Tier und Mensch am intakten Organismus eroffnet.Using 15N NMR measurements functional studies in rat organs were possible and could be demonstrated with the following examples:- 15N distributions to various rat organs depending on the effective time of the injected compounds;- measurement of biotransformation kinetics of [15NJglycine showing the continued metabolic activity of the isolated rat liver;- occurrence of intermediary metabolites of glycine.Wistar rats had received an injection of [15N2] urea and [15N2] glycine. The results establish that 15NNMR spectroscopy in connection with traditional 15N analysis is able to open new possibilities to study nitrogen turnover of plants, animals, and humans also in the intact organism.

Total nitrogen and 15N of urine samples were analysed using an emissionspectrometric 15N analyzer either coupled off-line with preceding Kjeldahl digestion or coupled on-line with an elemental analyzer, in order to draw a parallel between the two methods.The reliability of the results received with an NOI-6PC and Vario EL N coupled set was seen to be equivalent to that of the traditional off-line system. The on-line set can be recommended for routine estimation of 15N amounts in 15N-enriched urine samples that are usual in 15N organ function tests.

Hepatic detoxification capacities of three groups of infants aged about two were estimated using the [15N]methacetin elimination test, as well as standard serum parameters: Formerly hypotrophically born infants still too small for their age (n = 23) Patients suffering from severe liver diseases (n = 15) Patients without liver diseases (n = 14). 17 of the infants of group 1 showed 15N elimination rates as low as the rates of the liver-diseased patients of group 2. Compared to the infants of group 3, who had normal values, the findings reflect diminished hepatic monooxygenases activities in groups 1 and 2. On the other hand, the serum parameters of the infants of group 1 did not deviate from normal values estimated in group 3. Here only group 2 showed pathological values. Consequently, the [15N]methacetin test seems to be more sensitive in controlling hepatic parameters of growth retardations than the usual serum parameters used here. Further investigations have to answer the question to which proportion intrauterine malnutrition and postnatal effects, such as environmental living conditions, contribute to the retardation of liver function development in combination with growth retardation.

Membrane fusion of influenza virus is mediated by a conformational change of the viral membrane protein hemagglutinin (HA) triggered by low pH. By near UV CD spectroscopy, which is sensitive to the arrangement and mobility of aromatic amino acids in proteins, we have monitored continuously with a time resolution of 5 s the kinetics of structural alterations of the ectodomain of HA isolated from different influenza virus strains (H1 (A/PR 8/34), H2 (A/Japan), and H3 (X31)). To establish a functional correlation to structural alterations of the HA ectodomain reflected by the CD, we have measured the kinetics of the virus-erythrocyte fusion and of the inactivation of fusion by low pH preincubation of viruses. At acidic pH we found a multiphasic behavior of the CD signal recorded at 283 nm. Upon lowering the pH we detected first an increase of the CD amplitude, which is associated with the formation of a fusion-competent state of HA. The initial increase was followed by a continuous decline of CD amplitude, which can be ascribed to a transformation into a fusion-inactivated conformation that is in its early phase reversible as found for A/Japan. The half-time of the different phases of the CD signal depended on the virus strain, the temperature, and the acidic pH. The results support recent hypotheses that the fusion-competent conformation is an intermediate of the fusion-inactivated structure of HA.

Influenza virus hemagglutinin (HA) subtype H₇ expressed from a baculovirus vector in insect cells requires cysteine residues for palmitoylation. Mutant HA devoid of fatty acids shows hemagglutinating and hemolytic activities almost identical to those of the acylated wild-type HA (wt). Using a membrane mixing assay (R₁₈), neither the kinetics nor the pH dependence of fusion induced by wt or mutant HA was significantly different from virus-induced fusion. HA-induced fusion of insect cells with human erythrocyte ghosts could also be demonstrated by a cytoplasmic content mixing assay. Both species of recombinant HA induced the flow of lucifer yellow from preloaded ghosts into the cytoplasm of HA-bearing cells. This indicates that membrane fusion mediated by wild-type and fatty-acid-free HA includes both leaflets of the lipid bilayers. Hydroxylamine treatment of wt HA (H₇) and fatty-acid-free mutant HA present in lysates of insect cells led to the complete inhibition of hemolytic activity. Deacylation of spike proteins by NH₂OH treatment of virus particles resulted in a block of hemolytic activity in influenza virus subtypes H₇ and H₁₀ as well as of that in the togaviruses Semliki Forest and Sindbis virus. However, the same treatment did not affect subtypes H₂ and H₃ or two vesicular stomatitis virus serotypes. With such a differential effect whether or not fatty acids are present in the spike proteins of the different virus particles, hydroxylamine must have other effects than just deacylation, and therefore seems unsuitable for the study of the biological functions of acylproteins. Copyright 1995, 1999 Academic Press

Es wird gezeigt, daß der [15N]Methacetin-Urintest ein empfindliches, einfaches und nicht belastendes Verfahren ist, mit dem hepatozelluläre Schädigungen als Folge bestimmter Umwelteinflüsse am Arbeitsplatz gemessen werden können.Die Methode wird an 13 Textilreinigerinnen demonstriert, die bis zu 39 Jahre in ihrem Betrieb Perchlorethendämpfen ausgesetzt waren.Mit zunehmenden Expositionszeiten der Arbeiterinnen nehmen die 15N-Eliminations-geschwindigkeiten absinkenden hepatozellulären Monooxygenasen-Kapazitäten. Dies entspricht.It is shown that the [15N]methacetin urine test is a sensitive, simple, and non-distressing tool to measure hepatocellular injury as a consequence of certain environmental factors at the workplace.The method is demonstrated with 13 female textile cleaners who have been exposed to perchlorethylene for up to 39 years in their shop.Decreasing 15N elimination rates - equal to decreasing monooxygenase capacities - are seen to be correlated with increasing exposure times of the workers.

Im Zusammenhang mit der Einführung eines nichtinvasiven 15N-Leberfunktionstests entstand die Notwendigkeit, durch Interpretation der Meßergebnisse bestimmte Kenngrößen zu ermitteln, die eine spezifische Leberfunktion in einem Wert widerspiegeln.Es wurden drei Auswertemethoden erprobt, ein graphischer Meßwertausgleich, eine Regressionsrechnung unter alleiniger Verwendung der Eliminationsgleichung sowie die Auswertung auf der Grundlage eines Kompartmentmodells, welches Invasion und Elimination des Diagnostikums berücksichtigt. Zur Realisierung der zuletzt genannten Methode wurde das Computerprogramm PATMETH entwickelt. Vergleichende Betrachtungen, die auf der Grundlage der Ergebnisse von 250 ausgewerteten Tests vorgenommen wurden, zeigen die Überlegenheit der computergestützten Auswertemethode. Sie basiert auf einer einheitlichen theoretischen Grundlage, welche Willkür ausschliet, ermöglicht exakte Fehlerangaben der Testparameter und ist wesentlich zeitsparender.In connection with the introduction of a non-invasive 15N liver function test the necessity arose to evaluate certain parameters reflecting a specific liver function by interpretation of the measured values.There were tested three evaluation methods: a graphic fit of measured values, a linear regression by using only the elimination equation and the evaluation on the basis of a compartment model, which is considering invasion and elimination of the diagnostic agent. For realizing the last method there was developed the computer program PATMETH. Comparative investigations based on the evaluation of 250 tests show the superiority of the computer based calculation method. It is founded on a uniform theoretical basis excluding arbitrariness, it permits exact information about the error values of the test parameters and it is substantial time-sparing.

Following intravenous injections of [15N]glycine (97 at.% 15N, 400 mg in 1.5 ml isotonic saline) to Lewis rats several organs were excised. The time courses of the 15N NMR spectral (40.55 MHz) were measured at 37°C after cold (4°C) or warm (37°C) storage. The application of the Overhauser POE technique yielded signal enhancement by a factor of -2.7 and -1.3 in sceletal and heart muscle, respectively, at 37°C, but no enhancement in liver and kidney.In the time course of liver measurements at 37°C, intermediate metabolic products of glycine were observed, such as serine, glutamine, alanine, and tryptophane.

Stable isotopes, such as 13C, should be substituted for the long-lived radionuclide 14C in the 14C breath test when doing liver function tests in children and pregnant women. For comparison 13C, 15N-methacetin and 14C-methacetin were synthesized as suitable diagnostic agents. Methods are described for the measurement of 14C and 13C in the breath. After oral administration of labelled methacetin to healthy subjects and patients with liver diseases a good correspondence between 13C- and 14C-measurements in the same subject on the one hand, and a good discrimination between controls and patients on the other hand were shown. Findings with regard to 14C measurements in urine are discussed supporting the supposed advantage of 13C-methacetin over 14C-methacetin application.

Fusion between fluorescently labeled plasma membrane vesicles (PMV) and cells expressing vesicular stomatitis virus (VSV) glycoprotein (G-protein) was investigated by utilizing a lipid mixing assay based on fluorescence dequenching of octadecyl rhodamine (R18). The PMVs were prepared from Vero cells by hypotonic lysis. The G-protein was expressed on the cell surface either following infection with intact VSV or with an adenovirus vector (AdG12) containing the gene for the G-protein. Fusion was temperature and pH dependent and was inhibited by VSV G-antiserum. The pH dependence of PMV fusion paralleled that observed for VSV-cell fusion and VSV-induced syncytia formation. The kinetics of fusion followed an exponential dependence on time without an observable time lag after lowering pH. These findings indicate that dequenching R18-labeled PMV reliably represents the basic features of fusion of VSV with cells and can be used as a new tool in the study of fusion activity of virus envelope proteins expressed in cells. Copyright 1993, 1999 Academic Press

The fossil resin Glessite is characterized by elementary analysis, infrared spectroscopy, gaschromatography-mass spectrometry and by its distribution in Tertiary and Quarternary sediments. The chemotaxonomical fingerprint of alpha- and beta-Amyrine suggests that Glessite is derived from Elmiresin, a product of Burseracean angiosperms.

The influences of the gestational age (range: 28-36 weeks) and the postnatal age (range: 6–100 days) on the biotransformation capacity of the liver were studied in 51 preterm appropriate-for-gestational-age infants and in 20 preterm small-for-gestational-age infants using the [15N]methacetin urine test. Methacetin is a test drug assessing a two-step pathway of biotransformation including monooxygenation and conjugation. After oral administration of 3 mg [15N]methacetin/kg body-weight, the cumulative 15N excretion in urine during the consecutive 9 h was measured and used as a marker of microsomal biotransformation capacity. In preterm appropriate-for-gestational-age infants, the biotransformation capacity increases with gestational age as well as with postnatal age, but the strongest correlation could be found between cumulative [15N] excretion and postmenstrual age. Intrauterine growth retardation results in lower biotransformation capacity (26.3 ± 11.3 vs. 36.1 ± 9.6% [15N] excretion, expressed as percentage of intake) and disturbed postnatal development of this hepatic function. The data indicate that normal intrauterine development is a prerequisite for normal postnatal development of the biotransformation capacity, which might have consequences for the metabolism and efficacy of certain drugs in small-for-gestational-age infants.

Abstract335 [15N2]urea examinations to detect gastric Helicobacter pyloriinfection were performed using a uniform study protocol broadened to obtain a large quantity of various experimental data. The data were compiled and assessed in order to establish the most suitable parameter for a standardized test protocol. Second-hour urine following oral administration of the diagnostic agent was found to produce the clearest distinction between H. pylori-infected and non-infected persons. The threshold value of c= 0.06 (the quotient of 15Nexcessabundance in urinary ammonia and 15Nexcessabundance in the urinary urea) is not age-dependent Though less suitable on its own, the 15Nexcessabundance of urinary ammonia is useful as a second parameter for interpreting the results in the case of cvalues slightly below 0.06. The standardized test protocol is specified.

Large numbers of febrile illnesses associated with a great variety of clinical manifestations occur among children and adults each summer and autumn in temperate zones. There is increasing evidence that the family of enteroviruses,1 comprising the polioviruses, Coxsackie, and ECHO viruses, are responsible for a large proportion of these seasonal diseases. Since we already know of 51 antigenically distinct types in the family of enteroviruses, with more candidates awaiting their turn for admission, it seems highly desirable to learn of the clinical and epidemiologic potentialities of each virus. Such information can best be obtained during epidemics caused predominantly by one virus, and then only with clinical and epidemiologic data based exclusively on virologically proved cases. The present communication contains the results of such a study of an epidemic of ECHO Type 9 virus disease during the summer of 1957 in the city of Milwaukee, with an estimated population of

Leitfähigkeitsmessungen ergaben ein Maximum bei 3520 A, spektrographische Untersuchungen zeigten keine qualitativen Unterschiede in den Verunreinigungen zwischen verschieden lumineszierenden Kristallen. Die röntgenographische Untersuchung ergab, daß sämtliche Kristalle fehlgeordnet sind und im wesentlichen aus der 2-, 3- und 4-Schichten-Form bestehen.

Durch eine Isotopenverdunnungsanalyse mit D2O wird nicht niir der Wassergehalt einer Substanz oder Mischung, sondern auch der mogliche Anteil an acidem (austatischfahigem) Wasserstoff erfaβt. Es werden die Berechmmgswege fur die Wasserbestimmung in Systemen oline zusatzlichen austauschfahigen Wasserstoff sowie fur die Bestimmung aciden Wasserstoffs in wasserfreien Systemen angegeben. In Anwendungsbeispielen wurde der Wassergehalt von BaCl2·2H2O und Silicagel bestimmt. Weiterhin wurde ein leicht zu ermittelndes Maβ fur die Gesamtmenge saurer Gruppen in Braunkohle gefunden. Der Wassergehalt gewisser Erze und Gesteine kann durch Aufschluβ und gleichzeitige Isotopenverdunnungsanalyse bestimmt werden, wie am Beispiel der Wasserbestimmung an silicatischen Eisenerzen mit Hilfe von 20%iger heiβer DCl in D2O gezeigt werden konnte.

Heat destruction of types B and E Clostridium botulinumspores on whitefish chubs was observed to be dependent upon the relative humidity (RH) in the chamber in which fish were heated. Experimental conditions were designed to simulate those attainable in commercial fish-smoking plants. Low numbers of type E spores were destroyed with regularity, within 30 min, on fish which were held at an internal temperature of 77 C (170.6 F) in an atmosphere of at least 70% RH. However, an internal temperature of 82 C (179.6 F) and a minimum RH of 70% were required to destroy several hundred thousand type E spores. Quantitative estimates of spore destruction were arrived at with a modified most probable number procedure. Type E spore populations were reduced by 2 to 4 logarithms at 77 C (170.6 F), by 5 to 6 logarithms at 82 C (179.6 F), and by more than 6 logarithms at 88 C (190.4 F) when fish were heated in an atmosphere of 70% RH. A 5 to 6 logarithm reduction of spores was also observed when fish inoculated with type B spores were processed at 82 C (179.6 F) in an atmosphere of 70% RH.

A total of 1,071 whitefish chub samples were examined at eight stages of processing, including sampling aboard ship, various processing steps in the smoking plant, and display in retail cases. The frequency of Clostridium botulinumcontamination of freshly caught and eviscerated chubs was approximately 13 to 14%. The highest percentage of contamination (20%) was noted among chubs sampled at the brining step of processing. The prevalence of contamination among chubs sampled at other processing stages prior to the smoking operation ranged from 6 to 14%. Of 858 freshly smoked chubs that had been processed at 180 F for 30 min (internal temperature of loin muscle), 10 were contaminated with C. botulinum(1 Type B and 9 Type E). The use of heat-shocked (60 C for 15 min) and nonheat-shocked enrichment cultures in combination yielded a greater number of positive samples than either method yielded when used alone. Each toxic enrichment culture obtained was subcultured to obtain isolation of the toxigenic organism. Toxigenic pure cultures of C. botulinumwere obtained from 80% of the fish samples observed to produce toxic enrichment cultures.

In 21 low birth weight infants with two regimens of antibiotic therapy during the first 3 days of life possible hepatotoxic side effects were studied 8 days after the last administration of the tested drugs. Fourteen of the infants were treated with ampicillin/gentamicin and 7 received cefotaxime/gentamicin. The serum concentrations of total bile acids, the activities of transaminases in serum and the cumulative 15N excretion in urine after administration of 3 mg of 15N-labeled methacetin/kg of body weight were used as markers of hepatotoxic side effects. Neither the concentrations of total bile acids (22.6 ± 12.1 and 19.4 ± 10.8 mM, respectively) nor the activities of transaminases (alanine aminotransferase, 0.27 ± 0.06 vs. 0.30 ± 0.09 μmol/second/liter; aspartate aminotransferase, 0.46 ±0.11 us. 0.49 ± 0.10 μmol/second/ liter) were different between the two groups. In contrast the cumulative 15N excretion in urine was significantly lower in the group treated with cefotaxime/gentamicin than in the group treated with ampicillin/gentamicin (17.2 ± 6.4 vs. 33.0 ± 5.1 of intake; P< 0.01) and also lower than the reported age-related reference values. On the 28th day of life no differences could be found between the cumulative 15N excretion in the urine of the infants treated with cefotaxime/gentamicin and the reported age-related reference values of this test. The results indicate a limited capacity of the monooxygenase system of the liver of low birth weight infants during the first weeks of life and a specific reversible influence of cefotaxime on this hepatocellular system. Further investigations are required to evaluate the clinical relevance of this drug-specific inhibition of the hepatic monooxygenase pathway.