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Acta Biologica Hungarica
Authors:
D. Boonkusol
,
A. Dinnyés
,
Mayurachat Sa-ardrit
,
Saovaros Svasti
,
Tassanee Faisaikarm
,
J. Vadolas
,
Suthat Fucharoen
, and
Yindee Kitiyanant

A major clinical feature of patients with thalassemia is growth retardation due to anemia, therefore, the hematological parameters, weanling weight and post-weanling weight of pups obtained from vitrifiedwarmed embryo transfers were studied for the first time in this report. Two-cell embryos of four transgenic (TG) thalassemic mouse lines (BKO, 654, E2, and E4) were produced by breeding four lines of TG thalassemic males to wild-type (WT) females (C57BL/6J) and were cryopreserved by vitrification in straws using 35% ethylene glycol. After transfer of vitrified-warmed embryos, hematological parameters, spleen index, weanling and post-weanling weight were determined in TG and WT viable pups. In the BKO and 654 mice significantly abnormal hematological parameters and spleen index were observed compared to WT, E2 and E4 mice. The weanling and post-weanling weights of BKO and 654 pups were significantly less than that of the age-matched WT pups. However, no significant differences in weanling and post-weanling weight were found between WT and E2-TG or E4-TG pups. In conclusion, the four transgenic mice lines produced from cryopreserved embryo transfer retain the phenotype of the natural breeding mice indicating that these banked embryos are appropriate for thalassemia model productions.

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Synthetic seed technology is an alternative to traditional micropropagation for production and delivery of cloned plantlets. Synthetic seeds were produced by encapsulating nodal segments of C. angustifolia in calcium alginate gel. 3% (w/v) sodium alginate and 100 mM CaCl2 · 2H2O were found most suitable for encapsulation of nodal segments. Synthetic seeds cultured on half strength Murashige and Skoog medium supplemented with thidiazuron (5.0 μM) + indole-3-acetic acid (1.0 μM) produced maximum number of shoots (10.9 ± 0.78) after 8 weeks of culture exhibiting (78%) in vitro conversion response. Encapsulated nodal segments demonstrated successful regeneration after different period (1–6 weeks) of cold storage at 4 °C. The synthetic seeds stored at 4 °C for a period of 4 weeks resulted in maximum conversion frequency (93%) after 8 weeks when placed back to regeneration medium. The isolated shoots when cultured on half strength Murashige and Skoog medium supplemented with 1.0 μM indole-3-butyric acid (IBA), produced healthy roots and plantlets with well-developed shoot and roots were successfully hardened off in plastic pots containing sterile soilrite inside the growth chamber and gradually transferred to greenhouse where they grew well with 85% survival rate. Growth performance of 2 months old in vitro-raised plant was compared with in vivo seedlings of the same age. Changes in the content of photosynthetic pigments, net photosynthetic rate (PN), superoxide dismutase and catalase activity in C. angustifolia indicated the adaptation of micropropagated plants to ex vitro conditions.

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In 1930, Bortels showed that molybdenum is necessary for nitrogen fixation in Acetobacter, and in 1939 Arnon and Stout reported that molyb denum is essential for life in higher plants. Nitrogenase is the nitrogen-fixing enzyme complex, while nitrate reductase requires molybdenum for its activity. Molybdenum occurs in the earth crust with an abundance of 1.0–1.4 mg/kg. The molybdenum content of the vegetation is determined by the amount of this element in the soil and its pH-value. The weathering soils of granite, porphyry, gneiss and Rotliegendes produce a molyb denum-rich vegetation. Significantly poorer in Mo is the vegetation on loess, diluvial sands, alluvial riverside soils and especially on Keuper and Muschelkalk weathering soils, which produce legumes and, e.g. cauliflower with molybdenum deficiency symptoms. The molybdenum content of the flora decreases with increasing age. Legumes store the highest molybdenum levels in the bulbs of their roots; on average, they accumulate more molybdenum than herbs and grasses do. The danger of molybdenum toxicity in plants is small.

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T-2 toxin is primarily produced by Fusarium sp. abundant under temperate climatic conditions. Its main harmful effect is the inhibition of protein synthesis. Causing oxidative stress, it also promotes lipid peroxidation and changes plasma membrane phospholipid composition; this may lead to nervous system alterations. The aim of the present study was to examine whether a single dose of T-2 toxin administered at newborn age has any long-lasting effects on nervous system functions. Rat pups were treated on the first postnatal day with a single intraperitoneal dose of T-2 toxin (0.2 mg/bwkg). Body weight of treated pups was lower during the second and third week of life, compared to littermates; later, weight gain was recovered. At young adulthood, behavior was tested in the open field, and no difference was observed between treated and control rats. Field potential recordings from somatosensory cortex and hippocampus slices did not reveal any significant difference in neuronal network functions. In case of neocortical field EPSP, the shape was slightly different in treated pups. Long-term synaptic plasticity was also comparable in both groups. Seizure susceptibility of the slices was not different, either. In conclusion, T-2 toxin did not significantly affect basic nervous system functions at this dose.

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The aim of this study was to examine the effect of different stimulation protocols on oocyte granularity and to determine the influence of cytoplasmic granularity on further embryo development. A total of 2448 oocytes from 393 intracytoplasmic sperm injection (ICSI) cycles were analysed retrospectively. Oocytes were classified into 5 groups according to cytoplasmic granularity. (A) no granule or 1–2 small (<5 μm) granules; (B) more than 3 small granules; (C) large granules (>5 μm); (D) refractile body; (E) dense centrally located granular area. Correlation between characteristics of hormonal stimulation, oocyte granularity and embryo development was analysed. The occurrence of cytoplasmic granularity was influenced by the patient’s age and characteristics of stimulation. The type of granulation had no effect on fertilization rate and zygote morphology. However, some type of granulation resulted in a lower cleavage rate and more fragmented embryos. Our results provided additional information on how hormonal stimulation affects oocyte quality. While cytoplasmic granularity seems not to have an effect on fertilization and embryo development, the presence of refractile body in the oocyte is associated with reduced cleavage rates and impaired embryo development.

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Nausea is an unpleasant sensation usually referred to the stomach and sometimes followed by vomiting. Little is known about the subjective aspects of nausea because like pain and fatigue, it is a private sensation. We conceive of nausea as a complex control mechanism that signals us when not to eat. Our research in the areas of motion sickness and chemotherapy has led us to propose that we each have a dynamic threshold for nausea, which depends on the interaction of inherent factors and more changeable psychological factors, and that this threshold effects the individual's cognitive appraisal of both the nauseogenic stimulus and his/her bodily change in response to the nauseogenic stimulus. Inherent factors that are described are age, gender and race; psychological factors that are included are anxiety, expectation, anticipation and adaptation. The physiological responses that have been found to accompany nausea include an increase in sympathetic nervous system activity, a decrease in parasympathetic activity, an increase of abnormal dysrhythmic gastric activity, and an increase in plasma vasopressin. It is concluded that beneficial selective reduction of nausea will depend on a greater knowledge of the interaction of the psychological and physiological variables.

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Enzymes of sucrose metabolism viz. sucrose synthase (SS), sucrose phosphate synthase (SPS) and invertase were studied in the leaves of sugarcane (Saccharum officinarum L.) var. 'Co 7527' under the influence of spentwash as ferti-irrigation with respect to crop age. The activity of SS increased with increasing concentrations of spentwash while higher concentration (1,500 ppm BOD) lowered the activity by 1.42% and 4.16%, respectively, in 9 and 12 months old crop. SPS exhibited higher activity in 9 months old sugarcane with stimulatory effect at 1,000 and 1,500 ppm BOD treatment while invertase showed higher activity in 9 months old crop and declined at 12 months by exhibiting stimulatory effect at 1,000 ppm BOD. The elevation in SPS/invertase ratio at higher concentration of spentwash treatment can be attributed to the contributory factor for maintenance of high sucrose level. The study indicated that use of spentwash up to 1,500 ppm BOD as ferti-irrigation does not affect sucrose metabolism.

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Festuca specimens were collected on several spots in the Bükk mountains (Northern Hungarian Mountain Range, NE Hungary) in May 2002. On the area called “Galya-kopasza”, within the occurrence spot of Armeria elongata - made up by gabbro as basal rock -, interesting Festuca specimens belonging to the Festuca rupicola group of Festuca ovina agg. were also observed. On the basis of histological parameters of the leaves, namely long hairs, several among them differed from the typical Festuca rupicola specimens. Each specimen, and the different aged leaves within the specimens have the same structure. Describing the taxon as a separate species is confirmed, besides the unique structure of the leaves, also by deviations in the morphology of the panicle. Identification in the field in vegetative state is helped by the extremely long hairs on the abaxial epidermis of the leaves. The chromosome number of the specimens is 6n = 42. The plant was named after András Vojtkó, excellent botanist, great researcher of the flora and vegetation of the Bükk mountains. Locus classicus of the taxon is “Galya-kopasza” (Bükk Mts, NE Hungary). Type specimens were deposited in the Hungarian Natural History Museum (BP).

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We review the population ecology of Allium ursinum according to its life history, phenology, demography, dispersal, and population dynamics. Spatial distribution is reviewed on two spatial scales. First, on a broad scale over Europe, in relation to the habitat requirement of the species. Second, on a fine scale of individual patches, presenting some results about the local processes of density regulation and patch formation. We conclude that A. ursinum has a distinct, hitherto non-described, strategy for monopolizing space and dominating the forest floor. This Clan-of-Clones strategy has the following attributes. 1) Most of the seeds are dispersed close to the parent. 2) Seedling establishment is facilitated by the surrounding adults. 3) Allocation to vegetative reproduction is relatively small; its main role is to prolong local persistence. 4) The genet is not integrated physiologically, except for a transient connection between parent and offspring. An important consequence of the Clan-of-Clones strategy is that occupied patches can be fine-grained mosaics in terms of genetic composition and age groups.

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The new Dutch forest monitoring network is a policy-guided, multiple-use, GIS-oriented forest monitoring network. It is designed to provide the Dutch government, on a cyclic 8-year basis, with actual information about Dutch forests. Variables that reflect the information needs of policy makers and interest groups were selected by means of interviews and workshops. High-ranking variables are: wood stock, ownership, stand age, management status, biodiversity, carbon stock, and recreational use. These and other variables are being measured in 3622 forest sites, selected according to an unaligned systematic sampling design. The data are stored in an ORACLE data base, made accessible through the internet.  The Dutch forest area approximates a total of 360 000 ha; 46% is owned by private owners and organisations for nature conservation. Coniferous forests dominate (60%). Most forests were planted in 1940-1980. The total above ground volume of living trunk wood amounts to 56.3 million m3. The most common tree species are Quercus robur, Pinus sylvestris, and Betula pendula, the most common shrubs are Sorbus aucuparia, Prunus serotina, and Rhamnus frangula; while the most common other plant species are Deschampsia flexuosa, Rubus fruticosus s.l., and Dryopteris dilatata.

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