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Notes: Five cDNA clones were isolated from barley (Hordeum vulgare L.) that encoded mRNAs related to xyloglucan endotransglycosylase (XET). One of the clones encoded a protein with XET activity in vitro. Sequence comparisons revealed five families of XET-related sequences, one of which (containing two of the barley genes) was novel. Hybridization studies using clone-specific probes indicated that the corresponding genes were represented once, or possibly twice, in the barley genome. Treatment of dwarf mutants with gibberellic acid (GA3), or homozygosity at the ‘slender’ (sln1) locus, resulted in a 2.5-fold (approximately) stimulation of blade elongation rate. Three of the five clones detected mRNAs that were maximally expressed towards the base of the blade, and present in greater quantities in GA3-treated or slender seedlings. The remaining two clones detected mRNAs that were maximally expressed in the middle of the blade. Relative elemental growth rate (REGR) profiles of leaves growing with or without GA3 treatment revealed similar maximal REGR values despite a 2.5-fold difference in leaf elongation rate. Segments of GA3-treated leaves attained their maximal REGR values more rapidly, this being associated with enhanced expression of the three ‘basal’ XET-related mRNAs. Highest XET activities were detected in the base of the elongation zone, and in GA3-treated seedlings a second activity peak was observed near the distal end of the elongation zone. We conclude that there are likely to be several XET isoenzymes with different expression patterns, and identify those XET-related proteins potentially involved in leaf elongation.

Notes: Es wurden die Monosaccharid-, Disaccharid- und Stärke gehalte in Wurzeln und Spross von Rumex obtusifotius in Abhängigkeit vom Entwicklungsstadium untersucht. Es zeigte sich, dass der Reservestoffwechsel von Rumex obtusifolius durch drei Phasen gekennzeichnet ist. (1) Phase: Die Pflanze treibt nach dem Winter oder nach einem Schnitt aus. In dieser Zeit nimmt der Stärkegehalt in den Wurzeln ab. Es findet keine Einlagerung statt. (2) Phase: Ab etwa 30 em Wuchshöhe der blütentragenden Sprosse beginnt die Einlagerungsphase. Es erfolgi ein sprunghafter Ansiieg der Starkegehalte in den Wurzeln. Die Einlagerungsphase endet ausgangs der Blute mit dem Abschluss der Sprosstreckung. (3) Phase: Die Samen reifen ab, die blütentragenden Sprosse vertrocknen. Der Stärkegehalt der Wurzeln verändert sich nur noch geringfägig.Diese Befunde deuten darauf hin, dass die grösste Menge an Herbiziden vom Typ der Phenoxyverbindungen kurz vor und während der Blüte in die Speicherorgane von R. obtusifolius transportiert werden dürften. Storage metabolism in broad-leaved dock (Rumex obtusifolius)The amounts of monosaccharide, disaccharide and starch present in roots and shoots of Rumex obtusifotlius were investigated together with their relationship to the stage of development of the plant. It was found that storage metabolism of R. obtusifolius is characterized by three phases. Phase 1: the emergence of shoots after the winter or after cutting. During this period the starch content of the roots decreases and no storage lakes place. Phase 2: When the flower-bearing shoots are about 30 cm long. The storage phase now begins and an abrupt increase in the starch content of the roots occurs. The storage phase ends with the opening of the flower after the completion of shoot elongation. Phase 3. The seeds ripen and the flower-bearing shoots wither. Changes in the starch content of the roots are insignificant.These findings indicate that the majority of the phenoxy-type herbicides might well be translocated into the storage organs of R. obtusifolius shortly before and during flowering.Métabolisme des reserves chez la patience sauvage (Rumex obtusifolius)Les teneurs en monosaccharide, en disaccharide et en amidon présentes dans les racines et les pousses de Rumex obtusifolius ont étéévaluées en même temps que leur relation avec le stade de developpement de la plante. Il a été constaté que le métabolisme des réserves chez R. obtusifolius est caractérisé par trois phases: Phase 1: sortie des pousses aprés l'hiver ou après une coupe. Durant cette période, la teneur en amidon des racines décroít et il n'y a pas dc mise en réserve. Phase 2: lorsque les hampes florales ont environ 30 cm de long. La phase de mise en réserve commence alors et un brusque accroissement de la teneur en amidon se produit. La période de mise en réserve se termine avec l'ouverture de la fleur, aprés l'élongation complète de la tige. Phase 3: les semences mûrissent et les hampes florales se fanent. Les changements de teneur en amidon des racines sont insignifiants.Ces résultats montrent que la majorité: des herbicides de la série phénoxy peuvent aisément migrer dans les organes de stockage de R. obtusifolius peu de temps avant la floraison et pendant celle-ci.

Notes: Summary Abscisic acid (ABA) has been implicated as a regulatory factor in plant cold acclimation. In the present work, the cold-acclimation properties of an ABA-deficient mutant (aba) of Arabidopsis thaliana (L.) Heynh. were analyzed. The mutant had apparently lost its capability to cold acclimate: the freezing tolerance of the mutant was not increased by low temperature treatment but stayed at the level of the nonacclimated wild type. The mutational defect could be complemented by the addition of exogenous ABA to the growth medium, restoring freezing tolerance close to the wild-type level. This suggests that ABA might have a central regulatory function in the development of freezing tolerance in plants. Cold acclimation has been previously correlated to the induction of a specific set of proteins that have been suggested to have a role in freezing tolerance. However, these proteins were also induced in the aba mutant by low temperature treatment.

Notes: Summary Exogenously applied abscisic acid (ABA) induced frost hardening of Arabidopsis thaliana (L.) Heynh. The freezing tolerance of A. thaliana plantlets treated with ABA (15 mg/l) at a non-acclimating temperature (20 °C) appeared to increase even more rapidly than following a low temperature (4 °C) acclimation. Analysis of in vivo-labelled soluble proteins by two-dimensional gel electrophoresis revealed several low temperature — or ABA — induced proteins, which where not produced in non-acclimated plants. A subset of these proteins was induced by both low temperature and ABA treatments, suggesting that they might be directly involved in the frost hardening process in A. thaliana.

Notes: Abstract  Variation in the dehydrin gene family of ‘Himalaya’ barley (Hordeum vulgare L.) was studied using 3′ fragments of dehydrin cDNA clones (DHN1–4) as hybridisation probes. Each fragment specifically hybridised to the corresponding cDNA clone, but the 3′ fragment of DHN1 also hybridised to the very closely related DHN7 genomic clone. The same fragments were hybridised to Southern blots of genomic DNA prepared from a pool of 100 plants and digested with different restriction enzymes. DHN1 and DHN2 probes hybridised to one or two fragments, but only single bands were seen with DHN3 and DHN4 probes. When DNA was prepared from individual plants, the DHN1 and DHN2 probes each hybridised to single bands, representing one or other of the two bands in the pooled DNA sample. The ‘Himalaya’ population is therefore polymorphic, with two types of individual, designated P1 and P2. A cross between P1 and P2 types yielded an F1 with the same hybridisation profile as the pooled DNA. Segregation observed in the F2 generation was consistent with a 1 : 2 : 1 ratio. Therefore, P1 and P2 individuals contain RFLP alleles detected by DHN1 and DHN2 probes, with the alleles occurring in specific associations consistent with linkage between Dhn1 and Dhn2 loci. Allelic variation was also detected within the Dhn1 locus. Dehydrin RNA from P1 and P2 individuals was analysed by reverse transcription/polymerase chain reaction using primers specific for DHN1/DHN7 sequences. Sequencing of the amplified and cloned products indicated that P1 individuals expressed only the DHN1 sequence, and P2 individuals only DHN7. These results indicate that the DHN1 and DHN7 clones represent allelic alternatives at the Dhn1 locus (now designated Dhn1-1 and Dhn1-2, respectively). A stock that contained only P2 individuals was generated from a single seed, allowing hormonal regulation of Dhn1 gene expression to be studied without complications arising from polymorphism.

Notes: Summary It is reported about the blood pressure increasing effect of Aldosterone, Hydrocortisone and Prednisolone in infancy on one hundred and nine patients. Hydrocortisone shows in a dosis of 50 mg i.m. the highest increase in blood pressure with an average value of 36 mm Hg, Prednisolone as Solu-Decortin H®, in a dosis of 20 mg i. m. a lower of 30 mm Hg and Aldosterone, in a dosis of 0,5 mg i. m., only 17 mm Hg. The duration of the effect on the blood pressure ist about 30 min for Hydrocortisone and Prednisolone, for Aldosterone however only 15 min. Our experiments demonstrate that the adrenal hormones under investigation have the highest effect during the first trimenon. There is no relationship between the dosis and the effect (in milligram per kilogram body-weight) for Hydrocortisone, Prednisolone and Aldosterone in the investigated dosis of 5–20 mg respectively 2–8 mg respectively and 0.06–0.1 mg. It is postulated that adrenal hormones most likely potentiate the effect of catecholamines on the blood vessels.

Notes: Summary In 100 children without cardio-vascular abnormalities (aged between 4 hours and 9 months) simultaneous determinations of blood pressure were carried out using auscultatory and photoelectric methods as well as an electric method which is similar to electric impedance plethysmography. The results for, the systolic pressure using the electric method were almost identical to the intraarterial pressure recordings obtained by anglo-american authors by catheterisation of the umbilical artery. The values for blood pressure taken simultaneously with the auscultatory and photoelectric method were 3–4 mm Hg lower compared to the electric method. This is probably due to the high sensitivity of the electric method which records the exact first pulse wave that gets through as soon as the cuff pressure is lowered. According to our results all three methods give clinically reliable systolic pressure recordings. We prefer the photoelectric and electric method for use in newborns and infants for practical reasons since the Korotkoff-sounds are extremely difficult to hear. In comparison to the above mentioned methods the flush-method does not give exact results.

Notes: Summary A newly developed electric method which is similar to the electric impedance plethysmography for the determination of blood pressure was used with three different cuff sizes (2, 4 and 6 cm in width) in order to determine the optimal cuff size for use in newborns and infants. Since we were not interested, in absolute values, but in a comparison of the values obtained with different cuff sizes, the intraarterial blood pressure was not recorded simultaneously. Since the results obtained compared very well with those reported in the literature and with some of our own unpublished data for arterial pressure, the measurement of the intraarterial blood pressure does, not seem to furnish any further information anyway. According to our results the 2 cm cuff gives too high results as well as a wide range of deviation. Using 4 and 6 cm cuffs the differences in pressures obtained with our technique are very small. Since the 6 cm cuff is usully, too wide for the upper arm of a smaller infant and therefore tends to produce, errors, we recommend the use of the 4 cm cuff. The determination of the blood pressure in premature infants is mentioned.