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Journal of Radioanalytical and Nuclear Chemistry
Authors: G. Fürjes, G. Tóth, B. Peitl, R. Pórszász, B. Lelesz, R. Sári, A. Tóth, Z. Szilvássy, and J. Németh

Abstract  

In the present paper the development and application of a novel thrittene radioimmunoassay (RIA) are described. 125I-labeling of Tyr(0)-thrittene was performed by the iodogen-method and the mono-iodinated peptide, as RIA tracer, was separated by reversed-phase high performance liquid chromatography (HPLC). The RIA results show that the antiserum used in the radioimmunoassay turned to be C-terminal specific, without significant affinity to other members of the somatostatin peptide hormone family. Detection limit of the assay was 0.2 fmol/ml. This highly specific and sensitive thrittene RIA was used to investigate the distribution of thrittene in the rat gastrointestinal tract and other tissue samples. Different areas of the gastrointestinal tract and other tissues were removed from rats and after extraction the samples were processed for thrittene radioimmunoassay. Highest concentrations were found in the duodenum samples followed by jejunum and ileum, however, all the examined tissues contained highly enough thrittene for the measurement.

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Six pieces of grafts, 6.5 mm in diameter, 20 mm in length, were taken from each of 170 cadaver hindlimbs, using the cranial surface of the medial femoral trochlea for harvesting. The age of the horses varied between 4 months and 23 years. 30 limbs under the age of 12 years were selected for transplantation. Three of six grafts were transplanted into the medial femoral condyle using different combinations of tunnel depth and dilation. With ageing, a significant decline in transplantability was detected. In general, mosaicplasty cannot be recommended in horses above 11 years. Based on a previous clinical case (Bodo et al., 2000), a good surface alignment was indeed achieved with a combination of graft length drilling and dilation in most cases. However, the occasional entrapment of cartilage debris under the graft prevented perfect alignment in the present cadaver study in 27% of the grafts transplanted in this manner. Since the protrusion of grafts never exceeded 1.5 mm, we conclude that drilling 3–5 mm deeper than graft length with graft length deep dilation can avoid disadvantageous protrusion of the transplanted hyaline cartilage caps, achieving bone decompression at the same time.

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The performance of a semisynthetic bisexual lure (SBL, containing isoamyl alcohol, acetic acid and red wine) previously found attractive for a number of noctuids was compared with that of the respective synthetic sex attractants of Orthosia cerasi (=stabilis), O. cruda, O. gothica, O. incerta, Anorthoa munda and Conistra vaccini. The respective sex attractants performed significantly better in the Orthosia spp. than the SBL lure, which, although regularly catching low numbers of both females and males, did not differ significantly from zero catch in unbaited control traps. On the other hand, the SBL lure performed as well as the sex attractant in C. vaccini. Sizeable catches of C. rubiginea, C. rubiginosa and C. erythrocephala were also recorded in traps with the SBL lure. The SBL lure can prove to be a useful tool in ecological and faunistical studies of Conistra and related hibernating Xylenini species.

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Agrokémia és Talajtan
Authors: G. Gelybó, E. Tóth, C. Farkas, Á. Horel, I. Kása, and Z. Bakacsi

Climate change is expected to have a vigorous impact on soils and ecosystems due to elevated temperature and changes in precipitation (amount and frequency), thereby altering biogeochemical and hydrological cycles. Several phenomena associated with climate change and anthropogenic activity affect soils indirectly via ecosystem functioning (such as higher atmospheric CO2 concentration and N deposition). Continuous interactions between climate and soils determine the transformation and transport processes. Long-term gradual changes in abiotic environmental factors alter naturally occurring soil forming processes by modifying the soil water regime, mineral composition evolution, and the rate of organic matter formation and degradation. The resulting physical and chemical soil properties play a fundamental role in the productivity and environmental quality of cultivated land, so it is crucial to evaluate the potential outcomes of climate change and soil interactions. This paper attempts to review the underlying long-term processes influenced by different aspects of climate change. When considering major soil forming factors (climate, parent material, living organisms, topography), especially climate, we put special attention to soil physical properties (soil structure and texture, and consequential changes in soil hydrothermal regime), soil chemical properties (e.g. cation exchange capacity, soil organic matter content as influenced by changes in environmental conditions) and soil degradation as a result of longterm soil physicochemical transformations. The temperate region, specifically the Carpathian Basin as a heterogeneous territory consisting of different climatic and soil zones from continental to mountainous, is used as an example to present potential changes and to assess the effect of climate change on soils. The altered physicochemical and biological properties of soils require accentuated scientific attention, particularly with respect to significant feedback processes to climate and soil services such as food security.

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A simultaneous live/dead and acrosome staining, originally described for domestic mammals, was successfully applied on red deer (Cervus elaphus) and fallow deer (Dama dama) spermatozoa collected from the cauda epididymidis and vas deferens of shot stags. The staining is simple enough for routine application. Seven classes of spermatozoa were distinguished in the smears of frozen/thawed semen samples. Morphology, including cytoplasmic droplets, was evaluated as well. Percentage of live cells with intact acrosomes and with no other morphological aberrations might be a practical index of semen quality.

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Sperm samples were collected from the epididymides of 11 hunter-killed stags (Cervus elaphus hippelaphus) within 2 to 17 h post mortem in September 1991. Progressively motile spermatozoa were diluted and deep-frozen in tris-yolk extender by a procedure routinely used for bovine semen. The pre-freezing motility of spermatozoa from 6 stags was higher than 80%, while the sperm of 5 animals was found to be unsuitable for dilution. In the post-thawed sperm of six stags 40-50% of the spermatozoa showed progressive motility and the number of viable spermatozoa ranged from 8.6 to 26.7 × 106 per 0.25 ml straw. Two years later, three hinds were superovulated by the use of a progesterone-releasing intravaginal device (CIDR type G, Carter, Holt Harvey Plastic Products Group Ltd., Hamilton, New Zealand) for a period of 14 days and with follicle stimulating hormone (Folicotropin inj., Spofa, Prague). Each hind was inseminated artificially 60 h after the withdrawal of CIDR with thawed sperm injected into the uterus via the vagina. Seven days later the uteri were flushed out, as a result of which 3 early blastocysts + 1 ovum, 3 morulae + 4 ova, and 1 morula + 7 ova, respectively, were recovered from the three hinds. Deer embryos were frozen according to a glycerolbased freezing protocol. A further two years later two hinds were oestrussynchronised with CIDR type G and 300 IU PMSG (Folligon inj., Intervet, NL), and two of the thawed embryos were transplanted into two recipient hinds 7 days after heat. One of these gave birth to a normal stag fawn in June 1996. This was the first deer born in Hungary from embryo transfer. The results obtained indicate that sperm from top stags shot in the course of hunting can prove useful for the preservation of genetic material or in the development of the farmed deer system.

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Trap designs baited with the synthetic sex pheromone have been optimized for trapping of the western corn rootworm Diabrotica v. virgifera LeConte (Coleoptera: Chrysomelidae) (WCR), which has recently been introduced into Europe. The best trap design proved to be the sticky “cloak” trap (code name “PAL”), which catches only males, and is being used in many countries of Europe for detection and monitoring the spread of the new pest. Preliminarily the range of attraction (as defined by Wall and Perry, 1987) of the pheromone traps was estimated to be <10 m. The performance of yellow sticky plates (used by others for monitoring of the pest) was insignificant as compared to the activity of the pheromone baited traps, and yellow colour had no discernible effect on catches in pheromone traps. The known floral lure of WCR containing 4-methoxy-cinnamaldehyde and indole proved to be active also towards the population in Europe, attracting both females and males. Yellow colour slightly increased catches by the floral lure, hence a yellow sticky “cloak” trap has been developed (code name PALs). Pheromone baited PAL traps caught a total of about 4 times more beetles than the floral baited PALs, which latter however appeared to be preferentially active for females. When placed into the same trap, the pheromonal and floral lures did not interfere with each other's activity.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: I. Boros, G. Horváth, S. Lehel, T. Márián, Z. Kovács, J. Szentmiklósi, G. Tóth, and L. Trón

Abstract  

[11C]-labeled form of ten A2a adenosine receptor specific 8-styryl-7-methyl-xanthine derivatives ([11C]-caffeines) were synthesised by N-methylation of the corresponding 8-styryl-xanthine derivatives using [11C]-methyl iodide in optimized reaction conditions. The results show that the [11C]-methylations take place with excellent radiochemical yields (35–93%), and can be utilised easily in online preparations. These labeled ligands may facilitate the positron emission tomographic (PET) investigation of adenosine A2a receptors.

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Abstract  

The purpose of this investigation was to further elucidate calorimetric properties of cartilage samples from femoral head necrosis and osteoarthritis from live surgeries. The natural course of this disease is one of steady progression with eventual collapse of the femoral head, followed by secondary osteoarthritis in the hip joint. All samples showed a clear denaturation peak on the calorimetric curve. Cartilage obtained from necrotic femoral head required the lowest amount of energy for decomposition. The use differential scanning calorimetry as part of thermal analysis was a reliable method for differentiating.

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Abstract  

The glenohumeral joint is not a classical mass bearing joint, the treatment of primary osteoarthritis is conservative. In all other cases, when the arthritis is associated with unbalance of the soft tissues, the treatment solution of this pathology is arthroplasty. The purpose of this study was to examine the altered metabolism in human degenerated cartilage of the shoulder joint. With the rise of temperature an endothermic reaction was observed in all cases. The use differential scanning calorimetry as part of thermal analysis was a reliable method for differentiating normal hyaline cartilage from degenerated samples.

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