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The transitions between various developmental phases are critical in determining the ecological adaptation and yield of cereals. In order to elaborate a methodology for establishing the timing of the consecutive plant developmental phases from germination to the fully developed plant, regular measurements of changes in developmental components were carried out on one winter (Kompolti Korai) and one spring (Morex) barley cultivar in a model experiment. Under the controlled environmental conditions linear regression was characteristic of the associations between the chronological time and all or most of the time course data of plant height, tiller and leaf numbers. The initial growth of the spring barley was twice as intensive as that of the winter barley. The length of the stem elongation phases was similar for the two varieties, but the winter barley cultivar showed significantly more intensive stem growth compared to the spring barley. The spring barley reached all the plant developmental phases significantly earlier than the winter barley. For both cultivars, tillering continued till after first node appearance and there was a definite delay between first node appearance and the beginning of the stem elongation phase. The determination of the full series of phenophases, together with the evaluation of various yield components on the same plant, provide an excellent way of establishing plant developmental patterns and may make a significant contribution to achieving a better understanding of the associations between plant developmental patterns and the adaptation and yielding ability of cereals.

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The PC12 phaeochromocytoma cell line provides a useful model to study nerve growth factor-induced neuronal differentiation. The central signaling route of this process is mediated by the Ras-dependent extracellular signal-regulated kinase cascade. However, Ras-independent pathways are also stimulated by nerve growth factor and may contribute to differentiation signaling. One mediator for Ras-independent signal transduction in PC12 cells is phospholipase C-g that generates the second messengers diacylglycerol and inositol-trisphosphate. To probe the possible involvement of this enzyme in nerve growth factor-promoted differentiation, we used the phospholipase C inhibitor U73122 and the inositol-trisphosphate-receptor inhibitor Xestospongin C. Our results show that both chemicals block nerve growth factor-promoted neurite outgrowth, but the blockage of phospholipase C does not inhibit nerve growth factor-induced expression of c-fos, zif268 and transin genes. In addition, induction of these genes by nerve growth factor plus dibutyryl-cAMP is comparable in wild-type PC12 cells as well as in cells in which both Ras- and phospholipase C-g-mediated pathways are inhibited. The phospholipase C-g pathway thus belongs to those nerve growth factor receptor-originated signaling routes that contribute to the biological response of PC12 cells to nerve growth factor, but its gene activating potential does not have a major role in its neuritogenic effect.

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Bending, twitching and quivering are different types of tentacle movements observed during olfactory orientation of the snail. Three recently discovered special muscles, spanning along the length of superior tentacles from the tip to the base, seem to be responsible for the execution of these movements. In this study we have investigated the ultrastructure, contractile properties and protein composition of these muscles. Our ultrastructural studies show that smooth muscle fibers are loosely embedded in a collagen matrix and they are coupled with long sarcolemma protrusions. The muscle fibers apparently lack organized SR and transverse tubular system. Instead subsarcolemmal vesicles and mitochondria have been shown to be possible Ca2+ pools for contraction. It was shown that external Ca2+ is required for contraction elicited by high (40 mM) K+ or 10−4 M ACh. Caffeine (5 mM) induced contraction in Ca2+-free solution suggesting the presence of a substantial intracellular Ca2+ pool. High-resolution electrophoretic analysis of columellar and tentacular muscles did not reveal differences in major contractile proteins, such as actin, myosin and paramyosin. Differences were observed however in several bands representing presumably regulatory enzymes. It is concluded that, the ultrastructural, biochemical and contractile properties of the string muscles support their special physiological function.

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Short-term effects of orally administered plant lectins, with special reference to the Phaseolus vulgaris agglutinin (phytohaemagglutinin, PHA), were studied in growing rats.  The orally administered PHA elicited a dose-dependent accumulation of liquor with elevated pH in the proximal small intestine. Although the concentration of a-amylase activity did not change, total a-amylase activity slightly, but significantly increased in the gut. When a panel of plant lectins with different carbohydrate binding specificities was tested at the dose of 100 mg/kg body weight, most of them stimulated the secretion of liquor, but the total a-amylase activity was increased only by PHA, ConA or WGA.

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Acta Botanica Hungarica
Authors:
K. Szabó
,
G. Vasas
,
Á. Kiss
, and
A. Naumov
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Acta Botanica Hungarica
Authors:
K. Kiss
,
M. Duleba
,
Zs. Szilágyi
, and
A. Földi
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The effect of reduction of pressure on the shapes of the TG, DTG and DTA curves and the mass-spectra of hydroxide and carbonate phases was investigated in some typical Hungarian red muds. The pressure change caused different decomposition rates of the phases and resulted in better separation of the overlapping thermal curves; this led to advantages as regards phase analysis. For phase analysis the red muds were extracted with water, and the extracts and solid residues were identified by IR- and X-ray methods.

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Barley-infecting isolates of Wheat dwarf virus (WDV) were collected in the field in the vicinity of the cities Dunakiliti, Heves and Siófok, in Hungary. Viral genomic DNA was amplified by the rolling circle amplification technique, digested with Hind III, cloned into pBSK+ plasmid and sequenced. The clones were of the same size and showed above 99% identity to each other. Based on DNA sequences WDV-D01, WDV-H1 and WDV-H07 isolates showed high identity (94–99%) to isolates of WDV barley strain and Barley dwarf virus and lower identity to Oat dwarf virus (71% identity) and WDV wheat strains (85% identity).

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Purpose

This study aimed to examine the effectiveness of CO2 laser-assisted sclerectomy surgery (CLASS) in eyes with primary open-angle glaucoma (POAG) showing progression in spite of maximal local antiglaucomatous therapy.

Materials and methods

Patients with progressive POAG received CLASS treatment. We performed CLASS on 15 eyes (eight males and seven females). The primary endpoint was the change in the intraocular pressure (IOP), and additionally best spectacle-corrected visual acuity (BSCVA), C/D ratio (cup-to-disc), as well as use of antiglaucomatous drops were also investigated. Following the preoperative assessment, measurements were performed at 6-month follow-up.

Results

The average preoperative IOP was 26.13 ± 6.79 mmHg that dropped to 9.57 ± 4.09 mmHg at 1 day. IOP was stable at 1 month, 3 months, and 6 months. The BSCVA decreased to the 1-day and 1-week follow-up but returned to its original value to the 1-month check-up. Preoperatively, all patients were on maximal antiglaucoma drop therapy, after CLASS none of the patients needed antiglaucomatous treatment at 1 month. However, at 3 months, one of them needed antiglaucoma drops. C/D ratio showed non-significant changes.

Conclusions

CLASS procedure was found to be effective in decreasing IOP in POAG patients whose IOP was not compensated with maximal antiglaucomatous local therapy; patients needed significantly less local therapy following the CO2 laser surgery.

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