Degradation of polysaccharides containing uronic acid residues

A method for the selective degradation of polysaccharides containing uronic acid residues is described. It involves methylation of hydroxyl and carboxyl groups, base-catalysed elimination, and mild hydrolysis with acid. The degraded product is etherified with trideuteriomethyl or ethyl groups and hydrolysed, and the resulting mixture of etherified sugars is analysed, as the alditol acetates, by g.l.c.—m.s. Comparison of this analysis with the methylation analysis of the original polysaccharide gives information on the nature of the sugar residues on either side of the uronic acid residue.     

Enzymatic hydrolysis of n-substituted met-tRNA(M) and met-tRNA(F)

By addition of 1-(14)C-sodium acedate to the growth medium of Nocardia asteroides, it can be shown that the lipid content increases during the exponential phase, but does not vary during the stationary phase of the growth. Nocardic acid biosynthesis from the medium molecular weight fatty acids occurs chiefly during te stationary phase. As these compounds are localised in the cell walls, it becomes evident that the lipid envelope of the walls is still increasing when the cell growth and division have stopped.     

Lineare Systeme mit gesteuerten statistischen Impulsquellen

Summary From the communication engineers point of view the paper deals with networks consisting of linear filters and a special sort of controlled statistical pulse generators (SIG). The SIG responds to an analog signal with a sequence of Dirac impulses, where the probability for an output impulse at a given time depends on the instantaneous value of the input signal only. In connection with linear filters, however, systems can be realized in which the whole past of the input determines the statistical structure of the output. Therefore systems consisting of linear filters and SIGs (SIG networks) become interesting as models of biological systems, because in biological information processing transformations from analog signals into pulse trains occur very often. An example concerning the application of SIG systems in behavioural sciences will be discussed in a subsequent paper. In the present paper a theoretical analysis of the SIG and SIG networks is carried out by means of Statistical Communication Theory and Theory of Stochastic Processes. It is shown that under certain conditions very complex SIG networks can be treated with Correlation Theory. For one case not satisfying these conditions a solution on the base of Markoff processes is given.

---

---

Auszug aus einer von der Fakultät für Maschinenwesen und Elektrotechnik der Technischen Hochschule München genehmigten Dissertation.Herrn Prof. Dr.-Ing. H. Marko danke ich für das Interesse und die fördernde Kritik während des Entstehens der dieser Arbeit zugrundeliegenden Dissertation. Der Deutschen Forschungsgemeinschaft ist für die finanzielle Förderung der Untersuchungen zu danken. Die numerischen Berechnungen wurden auf der Rechenanlage TR4 des Leibniz-Rechenzentrums der Bayerischen Akademie der Wissenschaften durchgeführt.     

Genetische Untersuchungen bei angeborener organischer subvalvulärer Aortenstenose

Zusammenfassung Ausgehend von 45 Probanden mit angeborenen organischen subvalvulären Aortenstenosen wurden Familienuntersuchungen durchgeführt. 29 Probanden hatten eine einfache (isolierte) Subaortenstenose (Tabelle 1), 16 weitere einen mit zusätzlichen Herzdefekten wie angeborener valvulärer Aortenstenose (n=3), Ductus arteriosus persistens (n=7), Aortenisthmusstenose (n=5) und Ventrikelseptumdefekt (n=2) kombinierten Typ (Tabelle 2 u. 3).Die Häufigkeit der angeborenen organischen Subaortenstenose liegt wahrscheinlich zwischen 0,0065% und 0,0162%.Das Geschlechtsverhältnis beträgt bei Zusammenfassung der eigenen Fälle mit Literaturbeobachtungen 2 :1 (Tabelle 3 u. 4).In den Familien der 45 Probanden wurden alle lebenden Eltern, Geschwister sowie Kinder, z. T. auch Großeltern und weitere Verwandte untersucht. In 11 Fällen famden sich in den Sippen weitere Angehörige mit angeborenen Herzfehlern (Tabelle 1 u. 2). In der Geschwisterschaft von Kranken beträgt die nach dem Maximum-likelihood-Verfahren errechnete Erkrankungswahrscheinlichkeit p=0,0361±0,00205 (k=0,^rmin=1). Die Erkrankungswahrscheinlichkeit der Eltern, errechnet nach der Weinbergschen Probandenmethode, beträgt 3,3±1,9% (Tabelle 6).Ein Proband hat einen eineiigen, nicht betroffenen Zwillingsbruder.Das Durchschnittsalter der Väter der Probanden beträgt 30,6 Jahre, das der Mütter 28,6 Jahre und entspricht dem der Kontrollgruppe (Tabelle 7).Die Prüfung der Geburtenordnung nach dem Haldane-Smith-Verfahren ergab keine signifikante Differenz zwischen Beobachtung und Erwartung (Tabelle 8).Genetisch liegt den angeborenen organischen Subaortenstenosen vermutlich ein multifaktorielles genetisches System mit additiver Polygenie und Schwellenwerteffekt zugrunde.

---

Genetic investigations in congential organic subvalvular aortic stenosis

Summary Genetic investigations have been carried out on 45 propositi with congenital organic subvalvular aortic stenosis. From these, 29 had an isolated subvalvular aortic stenosis (see Table 1), 16 a type combined with other cardiac defects as valvular aortic stenosis (n=3), patent ductus arteriosus (n=7), coarctation of the aorta (n=5), and ventricular septal defect (n=2) (see Table 2 and 3).The incidence of this heart defect among all live births is probably 0.0065%–0.0162%.According to our own observations as well as to the literature the sex ratio of patients with organic subvalvular aortic stenosis is 2 :1 (see Table 3).In the families of the 45 propositi were examined all living parents, siblings and infants, in some cases also grand-parents and other family members. In all of them 11 relatives were affected with similar or-rarely-dissimilar congenital heart diseases (see Table 1 and 2). Using the maximum-likelihood-method, the risk of siblings to be affected is calculated as beeing p (k=0,^rmin=1). Using the Weinberg method the probability of parents to be affected is 3.3±1,9% (see Table 6).One index patient had a monozygotic co-twin who is not affected.The average age of the fathers is 30.6 years and of the mothers 28.6 years (see Table 7). There is no statistical difference between parental age and that of the control sample.The birth-order effect was examined in our 45 patients (see Table 8) by the Haldane-Smith-method. There is no difference between observation and expectation.The hypothesis of a multifactorial genetic background is supposed as mode of inheritance of congenital organic subvalvular aortic stenosis.

---

---

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Beiträge zur Ökologie des Aphano-Matricarietum Tüxen 1937

Zusammenfassung 1. An Hand von 101 Aufnahmen wird das Aphano-Matricarietum typicum and scleranthetosum im Unteren Eichsfeld in eine typische, eineRanunculus repens-, eineGnaphalium uliginosum-und eineJuncus bufonius-Variante gegliedert.2. Durch Bestimmungen des Bodenwassergehaltes und des pflanzenverfügbaren Wassers sowie durch Berechnung des W-Wertes nachEllenberg wird die Reihe der Varianten als Reihe zunehmender Feuchtigkeit charakterisiert.3. Bei zunehmender Dichte des Getreidebestandes nehmen die dominierenden Unkräuter stark ab, die schwach deckenden Unkräuter dagegen zu.4. Aus den Deckungswerten der soziologischen Tabelle werden Konkurrenzwirkungen zwischenMatricaria chamomilla, Aphanes arvensis undStellaria media belegt.

---

Summary 1. In two subassociations of a weed community (Aphano-Matricarietum typicum and scleranthetosum) 101 relevés are used for distinguish three subunits: a var. ofRanunculus repens, ofGnaphalium uliginosum and ofJuncus bufonius.By estimating the water contents and pF values of the soil and by calculating the water figure afterEllenberg this series of subunits is shown to be a series of increasing humidity.2. With increasing density of the cereal grasses, the stronger dominant weeds decrease, while the weaker ones increase.3. A method is described to calculate competition between the dominant weeds from the figures of the sociological relevés. Interactions have been found betweenMatricaria chamomilla at the one side andAphanes arvensis andStellaria media at the other side and vice versa.

     

A histochemically demonstrable thiaminepyrophosphatase activity in the sinusoidal endothelium of the liver

Summary A new histochemically demonstrable thiaminepyrophosphatase activity in liver tissue is described. It appears to be localized solely to the cytosomes of the sinusoidal endothelium. The activity, which requires high concentration of lead ion for its demonstration, has a high degree of substrate specificity. It resists formaldehyde fixation, ethanol and many inhibitors. The optimum pH is at pH 6.This study was supported in part by a grant from the Swedish Medical Research Council.     

Die Feinstruktur der peribronchialen Mikroparaganglien beim Meerschweinchen

Zusammenfassung Das Parenchym der peribronchialen Mikroparaganglien wird von zwei Zellarten aufgebaut: Chromaffine Zellen (Typ I-Zellen) und Hüllzellen (Typ II-Zellen).Die chromaffinen Zellen sind durch ihren reichen Gehalt an Vesikeln mit elektronendichtem Inhalt gekennzeichnet, deren Durchmesser 700–1300 Å beträgt. Markfreie Nerven ziehen an die Typ I-Zellen heran und bilden synaptische Kontakte aus. Die chromaffinen Zellen sind dabei der postsynaptische Teil der Verbindung. Die Hüllzellen entsprechen strukturell und funktionell den Schwannschen Zellen.Ein Mikroparaganglion wird von 10 bis 15 chromaffinen Zellen und deren Hüllzellen aufgebaut. Sie liegen dicht um fenestrierte Kapillaren, die von den Aa. bronchiales aus versorgt werden. Die Paraganglien sind von den Nervenzellen des peribronchialen Plexus durch dessen Perineurium getrennt. Selten findet man solitäre chromaffine Zellen innerhalb der Nervengeflechte. Es wird angenommen, daß die Paraganglien endokrine Funktionen erfüllen.

---

The fine structure of the guinea pig peribronchial micro-paraganglia

Summary The parenchyma of peribronchial microparaganglia consists of two different cell types: chromaffin cells (type I-cells) and surrounding cells (type II-cells).The chromaffin cells contain numerous vesicles with electron dense content, their diameter ranging from 700 to 1,300 Å. Unmyelinated nerves form synapses with type I-cells. The surrounding cells structurally and functionally correspond to Schwann cells.A micro-paraganglion consists of ten to fifteen chromaffin cells and their satellite cells. They are situated close to fenestrated capillaries, which are supplied from the Aa. bronchiales. A perineurial sheath separates the paraganglia from the nerve cells of the peribronchial plexus. Single chromaffin cells are found seldom within the nervous plexus.The paraganglia are thought to have an endocrine function.

     

A comparison between histochemically demonstrable Golgi-associated and bile canalicular TDP-ase activity in liver

Summary Histochemically demonstrable Golgi-associated TDP-ase activity in liver cells from cat, chicken, rat and frog has been investigated.This activity is highly substrate-specific, insensitive to aldehyde fixation, ethanol, acetate, lead and most enzyme inhibitors. It is stimulated by divalent manganese, calcium, magnesium and cobalt and optimum pH is at pH 6 to 7.The characteristics are identical for all four species but significant differences exist at a comparison with bile canalicular activity, Golgi-associated activity in other cells and biochemical findings.This study was supported in part by a grant from the Swedish Medical Research Council.     

Children's Hospital Admissions and Mother's Menstruation

Of 100 children''s emergency admissions to hospital nearly half (49%) were admitted during the mother''s paramenstruum. There was a statistically significant association between the mother''s menstruation and the child''s admission both for accidents and for illnesses. The eldest child in the family appeared to be most affected.     

Comparative studies on the regulation of DAHP synthetase activity in blue-green and green algae

Summary Regulation of DAHP synthetase activity was investigated in autotrophically grown blue-green and green algae. Members of the class of blue-green algae possess an enzyme, the activity of which is regulated by l-tyrosine and l-phenylalanine, whereby l-tyrosine is effective in 100 fold lower concentrations. DAHP synthetases of two organisms, Anabaena and Anacystis, were shown to belong to the V-type of allosteric enzymes.In contrast to the DAHP synthetase of blue-green algae regulation of this enzyme could not be demonstrated in two green algae, Ankistrodesmus and Maesotaenium. However, Euglena gracilis, both under conditions of mixotrophic and autotrophic growth, exhibits very effective regulation of this key enzyme; again, the inhibitors are tyrosine and phenylalanine. DAHP synthetase activity of Euglena has been purified about 40 fold; during this enrichment no separation of the enzyme activity inhibited by tyrosine and that by phenylalanine could be observed.