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61.
Terminal electron transport system (ETS)-activity of the sediment and plankton of Lake Balaton, the largest shallow lake of Central Europe was measured by tetrazolium-reduction biweekly during 1989–1990 and in the spring of 1991. Sediment proved to be enzymatically active to 30-35 cm down in the hypertrophic Keszthely Bay and to 15–20 cm down in the meso-eutrophic Siófok Basin. Sediment ETS-activity exceeded planktonic activity 15 to 24 fold.The total activity m–2 showed one or two order of magnitude higher respiratory potential in Lake Balaton than needed for complete oxidation of the planktonic primary production; most of this potential was detected in the upper 3–5 cm sediment layer in springs. Incubations of cell-free homogenates of sediment bacteria showed that ETS remains active days after death of organisms at low temperature. Accumulated postmortem ETS-activity derived from the benthic diatoms, bacteria, plankton deposit and dead summer macrophytes seems to be responsible for the high ETS-activity of the sediment in the warming periods in springs. These enzyme fractions may contribute to the rapid oxidation of the alkaline, well-aerated lake. 相似文献
62.
Dávid Kurszán Jász Ágnes Lilla Szilágyi Eszter Tuboly Bálint Baráth Anett Roxána Márton Petra Varga Gabriella Varga Dániel Érces Árpád Mohácsi Anna Szabó Renáta Bozó Kamilla Gömöri Anikó Görbe Mihály Boros Petra Hartmann 《Journal of cellular and molecular medicine》2021,25(11):5113-5123
Albeit previous experiments suggest potential anti-inflammatory effect of exogenous methane (CH4) in various organs, the mechanism of its bioactivity is not entirely understood. We aimed to investigate the potential mitochondrial effects and the underlying mechanisms of CH4 in rat cardiomyocytes and mitochondria under simulated ischaemia/reperfusion (sI/R) conditions. Three-day-old cultured cardiomyocytes were treated with 2.2% CH4-artificial air mixture during 2-hour-long reoxygenation following 4-hour-long anoxia (sI/R and sI/R + CH4, n = 6-6), with normoxic groups serving as controls (SH and SH + CH4; n = 6-6). Mitochondrial functions were investigated with high-resolution respirometry, and mitochondrial membrane injury was detected by cytochrome c release and apoptotic characteristics by using TUNEL staining. CH4 admixture had no effect on complex II (CII)-linked respiration under normoxia but significantly decreased the complex I (CI)-linked oxygen consumption. Nevertheless, addition of CH4 in the sI/R + CH4 group significantly reduced the respiratory activity of CII in contrast to CI and the CH4 treatment diminished mitochondrial H2O2 production. Substrate-induced changes to membrane potential were partially preserved by CH4, and additionally, cytochrome c release and apoptosis of cardiomyocytes were reduced in the CH4-treated group. In conclusion, the addition of CH4 decreases mitochondrial ROS generation via blockade of electron transport at CI and reduces anoxia-reoxygenation-induced mitochondrial dysfunction and cardiomyocyte injury in vitro. 相似文献
63.
Péter Poczai Kinga Klára Mátyás István Szabó Ildikó Varga Jaakko Hyvönen István Cernák Ahmad Mosapour Gorji Kincső Decsi János Taller 《Plant Molecular Biology Reporter》2011,29(4):906-918
The globally widespread genus Nymphaea exhibits a wide range of morphological and taxonomical diversity. The intrusion of a cultivated variety by progressive propagation
and its affect on aquatic habitat is demonstrated in this case study. We have studied the genetic diversity, population, and
stand structure of the neophyte Nymphaea × ‘Panama Pacific’ as well as other species found in Lake Hévíz and dikes nearby using inter-simple sequence repeat (ISSR)
markers. The ISSR assay revealed a low genetic variability for the small populations of Nymphaea caerulea, Nymphaea lotus var. thermalis, and a medium level for Nymphaea alba, Nymphaea rubra var. longiflora, and Nymphaea × ‘Panama Pacific’. The evolutionary genetic status of individuals found in the overlapping cultivation area of Nymphaea × ‘Panama Pacific’ and N. caerulea was affirmed to be of hybrid origin by reticulate network analysis and with morphological parameters. The Bayesian analysis
of hybrid classes and the segregation of the ISSR markers also confirmed the hybrid origin of the individuals in question
and revealed that they are falling into F2 or latter genotype frequency classes, indicating the viability and fertility of
the hybrids. The set of analyzed species by phylogenetic network analysis of ISSR data has been divided into three major groups
according to their evolutionary patterns (subg. Barachyceras, Lotos, and Nymphaea). Our results are in accordance with these three major subgenera within Nymphaea. 相似文献
64.
Ilona B. Muskó Csilla Balogh Ádám Péter Tóth Éva Varga Gyula Lakatos 《Hydrobiologia》2007,590(1):65-74
The water level of Lake Balaton (a large, shallow lake) was extremely low in 2003, after a dry period of several years. Due
to the intensive precipitation in 2004, a regeneration period commenced. Stones of the littoral zone were sampled near the
water surface and from the lake bottom four times in both years at four sampling stations. Malacostraca in the encrustation
of the stones were represented by Ponto-Caspian immigrants: the invasive amphipods Chelicorophium curvispinum and Dikerogammarus spp. (D. haemobaphes and D. villosus), the mysid Limnomysis benedeni and the isopod Jaera istri. The amphipods dominated in both years. Species of the amphipod genus Dikerogammarus were relatively less abundant than the amphipod C. curvispinum in the regeneration period as compared to the drought period of 2003. Maximal density of Malacostraca (ind. m−2 stone surface) was 69,953 in 2003 and 82,465 in 2004. Vertical stratification of animal numbers and specific taxa occurred
in May 2003 and throughout the year in 2004, with some exceptions. Many more Malacostraca individuals were recorded at the
lake bottom than near the water surface.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
65.
Intraspecific variability in root colonization, extraradical growth pattern, and survival after cold storage of Lactarius deliciosus isolates was determined in pure culture conditions using Pinus pinaster as a host plant. The ectomycorrhizal ability of L. deliciosus at 30, 45, and 60 days from inoculation was highly variable among isolates and was negatively correlated to the age of the
culture (time elapsed from isolation). The formation of rhizomorphs was related to colonization ability, but no relationship
was found between colonization and formation of extraradical mycelium. The final colonization achieved at 60 days from inoculation
was not related to the tree species under which the sporocarps were collected. However, isolates from sporocarps collected
under P. pinaster colonized more rapidly the seedlings than those collected under other pine species. The climatic range of the sporocarps
from which the isolates were obtained (maritime vs. continental) was not related to the formation of mycorrhizas at 60 days
from inoculation. However, isolates from sporocarps collected from a maritime climate area colonized more rapidly the P. pinaster seedlings than those collected from a continental zone. Tolerance to cold water storage of L. deliciosus was also isolate dependent. Growth revival in agar was obtained from most of the isolates after 28 months of cold storage
at 4°C, but only 10 out of 29 isolates showed unaffected growth. The ITS rDNA alignment of all the L. deliciosus isolates showed a low variability with identities over 99%. Most of the variation was detected in the ITS1 region and consisted
in single nucleotide changes and/or punctual indel mutations. The number of base differences per sequence from averaging over
all sequence pairs was 1.329, which is in the low range when compared with other ectomycorrhizal species. No ITS pattern due
to geographical origin of the isolates could be discerned. 相似文献
66.
Wang GZ Haile PA Daniel T Belot B Viet AQ Goodman KB Sha D Dowdell SE Varga N Hong X Chakravorty S Webb C Cornejo C Olzinski A Bernard R Evans C Emmons A Briand J Chung CW Quek R Lee D Gough PJ Sehon CA 《Bioorganic & medicinal chemistry letters》2011,21(24):7291-7294
A series of biarylsulfonamides was identified as hCCR2 receptor antagonist but suffered from high plasma protein binding resulting in a >100 fold shift in activity in a functional GTPγS assay run in tandem in the presence and absence of human serum albumin. Introduction of an aryl amide with ethylenediamine linker led to compounds with reduced shifts and improved activity in whole blood. 相似文献
67.
Judit Kocsis Tamás Mészáros Balázs Madaras Éva Katalin Tóth Szilárd Kamondi Péter Gál Lilian Varga Zoltán Prohászka George Füst 《Cell stress & chaperones》2011,16(1):49-55
Recently, we reported that high soluble Hsp70 (sHsp70) level was a significant predictor of mortality during an almost 3-year-long
follow-up period in patients with colorectal cancer. This association was the strongest in the group of <70-year-old female
patients as well as in those who were in a less advanced stage of the disease at baseline. According to these observations,
measurement of the serum level of sHsp70 is a useful, stage-independent prognostic marker in colorectal cancer, especially
in patients without distant metastasis. Since many literature data indicated that measurement of C-reactive protein (CRP)
and other acute phase proteins (APPs) may also be suitable for predicting the mortality of patients with colorectal cancer,
it seemed reasonable to study whether the effect of sHsp70 and other APPs are related or independent. In order to answer this
question, we measured the concentrations of CRP as well as of other complement-related APPs (C1 inhibitor, C3, and C9) along
with that of the MASP-2 complement component in the sera of 175 patients with colorectal cancer and known levels of sHsp70,
which have been used in our previous study. High (above median) levels of CRP, C1 esterase inhibitor (C1-INH), and sHsp70
were found to be independently associated with poor patient survival, whereas no such association was observed with the other
proteins tested. According to the adjusted Cox proportional hazards analysis, the additive effect of high sHsp70, CRP, and
C1-INH levels on the survival of patients exceeded that of high sHsp70 alone, with a hazard ratio (HR) of 2.83 (1.13–70.9).
In some subgroups of patients, such as in females [HR 4.80 (1.07–21.60)] or in ≤70-year-old patients [HR 11.53 (2.78–47.70)],
even greater differences were obtained. These findings indicate that the clinical mortality–prediction value of combined measurements
of sHsp70, CRP, and C1-INH with inexpensive methods can be very high, especially in specific subgroups of patients with colorectal
cancer. 相似文献
68.
69.
70.
Neuronal calcium channel antagonists. Discrimination between calcium channel subtypes using omega-conotoxin from Conus magus venom 总被引:13,自引:0,他引:13
B M Olivera L J Cruz V de Santos G W LeCheminant D Griffin R Zeikus J M McIntosh R Galyean J Varga W R Gray 《Biochemistry》1987,26(8):2086-2090
The omega-conotoxins from the venom of fish-hunting cone snails are probably the most useful of presently available ligands for neuronal Ca channels from vertebrates. Two of these peptide toxins, omega-conotoxins MVIIA and MVIIB from the venom of Conus magus, were purified. The amino acid sequences show significant differences from omega-conotoxins from Conus geographus. Total synthesis of omega-conotoxin MVIIA was achieved, and biologically active radiolabeled toxin was produced by iodination. Although omega-conotoxins from C. geographus (GVIA) and C. magus (MVIIA) appear to compete for the same sites in mammalian brain, in amphibian brain the high-affinity binding of omega-conotoxin MVIIA has narrower specificity. In this system, it is demonstrated that a combination of two omega-conotoxins can be used for biochemically defining receptor subtypes and suggested that these correspond to subtypes of neuronal Ca2+ channels. 相似文献