Interest surrounds the role of an NADPH oxidase-like enzyme in hypoxic pulmonary vasoconstriction (HPV). We have studied the effects of the NADPH oxidase inhibitors iodonium diphenyl (ID) and cadmium sulphate (CdSO4) upon HPV of isolated rat pulmonary arteries (n = 73, internal diameter 545± 23 mm). Vessels were preconstricted with prostaglandin F2a (PGF2a, 0.5 or 5 mM) prior to a hypoxic challenge. ID (10 or 50 mM), CdSO4 (100 mM) or vehicle (50 ml) was added for 30 min before re-exposure to PGF2a and hypoxia. ID and CdSO4 significantly inhibited HPV. In vessels preconstricted with 5 mM PGF2a, ID (10 and 50 mM) reduced HPV from 37.4± 5.6 % to 9.67± 4.4 % of the contractile response elicited by 80 mM KCl (P<0.05) and from 30.1± 5.0 % to 0.63± 0.6% 80 mM KCl response (P<0.01), respectively. CdSO4 (100 mM) reduced HPV from 29.4±4.0 % to 17.1±2.2% 80 mM KCl response (P<0.05). In vessels preconstricted with 0.5 mM PGF2a, ID (10 and 50 mM) reduced HPV from 16.0± 3.15% to 3.36± 1.44 % 80 mM KCl response (P<0.01) and from 15.0± 1.67 % to 2.82± 1.40 % 80 mM KCl response (P<0.001), respectively. Constriction to PGF2a was potentiated by ID. ID and CdSO4, at concentrations previously shown to inhibit neutrophil NADPH oxidase, attenuate HPV in isolated rat pulmonary arteries. This suggests that an NADPH oxidase-like enzyme is involved in HPV and could act as the pulmonary oxygen sensor., R. D. Jones, J. S. Thompson, A. H. Morice., and Obsahuje bibliografii
In this work, the injuries caused by clethodim herbicide application as well as the use of exogenous salicylic acid (SA) as a protective agent against clethodim in Zea mays leaves were examined. Although the target for clethodim is the inhibition of acetyl coenzyme A carboxylase (ACCase) which is the key enzyme for fatty acid biosynthesis, it can indirectly affect the photosynthetic machinery, gaseous exchange and some biochemical parameters. Clethodim application caused chlorosis and yellowing of leaf-tip parts. Higher doses caused browning or reddening of leaves and sometimes dead parts of the leaf margins were observed. The rate of photosynthesis was significantly lowered and the pigments content was highly reduced as a response to clethodim spraying. Moreover, other gas-exchange properties were altered. Furthermore, accumulation of high amounts of carbohydrates, proteins and proline were detected. SA spraying three days prior clethodim application caused partially or totally disappearance of clethodim injuries and kept the leaves similar to those of control. Improved photosynthesis and enhanced pigments content were observed in leaves treated with SA. Other analyzed parameters showed values similar to those of the corresponding control. From the experimental work, an evidenced role of SA working against clethodim effects was suggested and discussed in this paper., D. E. M. Radwan, D. M. Soltan., and Obsahuje bibliografii
Studie otevírá diskusi s názory o původu a vývojových proměnách keramiky vytáčené kompletně na hrnčířském kruhu a opatřené pásovou výzdobou. Tato keramická třída byla používána v raném středověku (po dobu asi jednoho století) komunitami žijícími na jihu Velkopolska a v severovýchodní části Dolního Slezska. Dosavadní představy naznačující úzký vztah s obdobně zdobenou keramikou produkovanou v severních částech Čech jsou přehodnoceny s poukazem na vnitřní rozmanitost celé keramické třídy. Inspirační zdroje nepřicházely pouze z jihu (tj. z Čech), ale také ze severu (Pomořansko) a ze západu (oblast středního toku Labe). V rámci tohoto druhu keramiky lze pozorovat proměny, které se v produkci malých lokálních komunit objevují nezávisle na vnějších impulsech. and The article underlines the need to re-discuss the prevailing views in archaeological literature on the provenance and transformation stages of completely wheel-turned ceramics decorated with zoned ornament. This class of ceramics was used in the Early Middle Ages (for about 100 years) by communities living in the area of southern Greater Poland and the north-eastern part of Lower Silesia. The previous ideas suggesting a close relationship between zoned ceramics and vessels produced in northern Bohemia are reconsidered, with the internal diversity of zoned ceramics being pointed out. We argue that inspiration in ceramics manufacturing came not only from the south (Bohemia), but also from the north (Pomerania) and the west (the middle Elbe region), and that there were also changes that appeared independently of these impulses in the ceramics production of small, native communities.
Floristic composition, morphological functional types, and altitudinal distribution pattern for C4 species were studied in Yunnan province, South-western China. 159 species, in 6 families and 60 genera, were identified with C4 photosynthesis. 93 % of these C4 species were found in Monocotyledoneae, e.g. Cyperaceae (18 species), Gramineae (129 species), and Commelinaceae (1 species), the other 7 % was in Dicotyledoneae, e.g. Amaranthaceae (5 species), Portulacaceae (4 species), and Chenopodiaceae (2 species). Hence C4 plants mainly occurred in very few families in the tropical region. Compared with those in semi-arid grasslands and arid deserts in North China, more C4 grasses and much less Chenopodiaceae C4 species occurred in the tropical region. This indicates the physiological responses of C4 plants from the two families are very different. Chenopodiaceae C4 species may be more fit semi-arid and arid environments, while C4 grasses are more fit the moist tropical conditions. There was a strong relationship between C4 distribution and altitude in the tropical region. Altitudinal distribution pattern for C4 species in the region was consistent with altitude, climate, and habitats.
Floristic composition, morphological functional types and habitat distributions for C4 species were studied in Xinjiang, North-western China. 89 species, in 9 families and 41 genera, were identified with C4 photosynthesis. 48 % of these C4 species were found in Monocotyledoneae, e.g. Cyperaceae (5 species), Gramineae (38 species), the other 52 % was in Dicotyledoneae, e.g. Chenopodiaceae (29 species), Amaranthaceae (7 species), and Polygonaceae (5 species). Compared with those in semi-arid grasslands in North China and tropical forests in South China, more plant families were found with the occurrence of C4 plants in this arid region. Relatively higher annual species (63 %), shrubs (18 %), and Chenopodiaceae C4 species (33 %) compositions were the primary characteristics for the C4 species occurring in Xinjiang, and this was remarkably related with its arid environment. More Chenopodiaceae C4 species occurring in the region suggested that this type of C4 species may have higher capacity to fit the air and soil droughts. There was a strong relationship between C4 occurrence and habitat distributions, more than half of the total 89 C4 species were found in disturbed and cultivated lands and early stages of vegetation successions, indicating C4 occurrence was not only related with climate changes, but also with land uses and vegetation dynamics.
Twelve tundra swans, Cygnus columbianus (Ord), from Nevada and one from New Mexico were collected and examined for schistosomes. Mature worms, determined as Allobilharzia visceralis, were found in 92% of the swans, in the inferior mesenteric vein of the large intestine and its branches. In 12 cases, there was endophlebitis of the inferior mesenteric vein. The morphology of the worms is consistent with the recently described genus Allobilharzia. Placement in this genus was confirmed also by phylogenetic analysis of nuclear 28S, 18S and, internal transcribed spacer (ITS) ribosomal DNA (rDNA), and mitochondrial cytochrome oxidase I (CO1) sequences. Data further suggest the worms are conspecific with the European A. visceralis, the only described species of the genus and which was found to be the sister taxon to the most diverse avian schistosome genus, Trichobilharzia. This is the first report of a schistosome infection from native swans in North America.
a1_We investigated the potential neuroprotective effect of transient hypertension on neuronal cell death induced by ischemia-reperfusion. Recovery of neurons, terminally differentiated cells, is almost entirely dependent upon active transcription and repair of DNA damage. We focused on the histochemical detection of distribution of NOR (argyrophylic nucleolar proteins) reflecting nucleolar integrity, immunohistochemical detection of PARP-1 (poly(ADP-ribose) polymerase-1), MADD (mitogen-activated death domain), a protein accumulated in nucleoli upon stimulation by ischemia, the active form of caspase-3, a universal proteolytic enzyme of apoptosis. The terminal deoxynucleotidyl-transferase (TdT)-mediated dUTP-biotin nick-end-labeling method (TUNEL) proved the presence of in situ DNA fragmentation. We used the model of transient focal cerebral ischemia in rats with occlusion of middle cerebral artery. In experimental group of rats, the transient hypertension was induced by constriction of the abdominal aorta. The period of ischemia lasted 15, 30, 60 and 120 min followed by 48 h of reperfusion. We examined the frontal lobe of the ipsilateral hemisphere for apoptosis of neurons and compared it with the intact brain tissue. In normotensive rats with transient focal cerebral ischemia, we found disintegrated nucleoli of cortical as well as subcortical neurons at all investigated periods of ischemia, whereas the neurons of intact animals showed compact nucleoli with a few satellites. Nuclear positivity for MADD and PARP-1 was apparent in the neocortex after 15 min and peaked after 30 min of ischemia. On the other hand, the subcortical neurons showed nuclear positivity after 60 and 120 min. The immunohistochemical reaction for active caspase 3 was apparent after 30 min onwards predominantly in the cortex. The TUNEL staining was distinct after 60 and 120 min., a2_In hypertensive rats, we found nucleolar disintegration, positivity for MADD, PARP-1 and caspase 3 after 30 min cortically and subcortically, followed by TUNEL positive staining of cortical neurons after 60 and 120 min. In summary, we detected delayed activation of neuronal apoptosis in transiently hypertensive rats with focal cerebral ischemia compared to normotensive animals. The apoptotic phenotype was confirmed by a panel of complementary methods showing rapid proteolysis-nucleolar segregation, MADD, PARP-1 and caspase-3 positivity as well as ultimate DNA fragmentation proved by the TUNEL assay., M. Smrčka, M. Horký, F. Otevřel, Š. Kuchtíčková, V. Kotala, J. Mužík., and Obsahuje bibliografii
There is considerable evidence linking alcohol consumption and sedation and TRH in the brain septum. Moreover, innate septal TRH concentration is inversely related to the degree of ethanol preference. Recently we demonstrated in rats that four-week ethanol drinking increased the septal TRH content by 50 %. We had shown previously that ethanol induces neuronal swelling, which is known to evoke the secretion of hormones, peptides and amino acids from various types of cells. We have therefore explored the effect of hyposmotic medium and of 80 and 160 mM ethanol and 80 mM urea (both permeant molecules) in isosmotic and hyperosmotic (preventing cell swelling) media on the in vitro release of TRH by the rat septum. Lowering medium osmolarity resulted in a hyposmolarity-related increase in TRH secretion. Both ethanol and urea stimulated TRH release only in isosmolar solution. Our data indicate that ethanol in clinically relevant concentrations can induce TRH release from the septum by a mechanism involving neuronal swelling., J. Kučeorvá, V. Štrbák., and Obsahuje bibliografii