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91.
92.
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
93.
Neuwelt EA Bauer B Fahlke C Fricker G Iadecola C Janigro D Leybaert L Molnár Z O'Donnell ME Povlishock JT Saunders NR Sharp F Stanimirovic D Watts RJ Drewes LR 《Nature reviews. Neuroscience》2011,12(3):169-182
The delivery of many potentially therapeutic and diagnostic compounds to specific areas of the brain is restricted by brain barriers, of which the most well known are the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier. Recent studies have shown numerous additional roles of these barriers, including an involvement in neurodevelopment, in the control of cerebral blood flow, and--when barrier integrity is impaired--in the pathology of many common CNS disorders such as Alzheimer's disease, Parkinson's disease and stroke. 相似文献
94.
Montipora white syndrome (MWS) results in tissue-loss that is often lethal to Montipora capitata, a major reef building coral that is abundant and dominant in the Hawai'ian Archipelago. Within some MWS-affected colonies in Kane'ohe Bay, Oahu, Hawai'i, we saw unusual motile multicellular structures within gastrovascular canals (hereafter referred to as invasive gastrovascular multicellular structure-IGMS) that were associated with thinning and fragmentation of the basal body wall. IGMS were in significantly greater densities in coral fragments manifesting tissue-loss compared to paired normal fragments. Mesenterial filaments from these colonies yielded typical M. capitata mitochondrial haplotypes (CO1, CR), while IGMS from the same colony consistently yielded distinct haplotypes previously only found in a different Montipora species (Montipora flabellata). Protein profiles showed consistent differences between paired mesenterial filaments and IGMS from the same colonies as did seven microsatellite loci that also exhibited an excess of alleles per locus inconsistent with a single diploid organism. We hypothesize that IGMS are a parasitic cellular lineage resulting from the chimeric fusion between M. capitata and M. flabellata larvae followed by morphological reabsorption of M. flabellata and subsequent formation of cell-lineage parasites. We term this disease Montiporaiasis. Although intra-specific chimerism is common in colonial animals, this is the first suspected inter-specific example and the first associated with tissue loss. 相似文献
95.
With 1.6 million casualties annually and 2 billion people being infected, tuberculosis is still one of the most pressing healthcare challenges. Here we report on the new computational docking algorithm FRIGATE which unites continuous local optimization techniques (conjugate gradient method) with an inherently discrete computational approach in forcefield computation, resulting in equal or better scoring accuracies than several benchmark docking programs. By utilizing FRIGATE for a virtual screen of the ZINC library against the Mycobacterium tuberculosis (Mtb) enzyme antigen 85C, we identified novel small molecule inhibitors of multiple drug-resistant Mtb, which bind in vitro to the catalytic site of antigen 85C. 相似文献
96.
Recent work on animal personalities has demonstrated that individuals may show consistent behaviour across situations and contexts. These studies were often carried out in one location and/or during short time intervals. Many animals, however, migrate and spend their life in several geographically distinct locations, and they may either adopt behaviours specific to the local environment or keep consistent behaviours over ecologically distinct locations. Long-distance migratory species offer excellent opportunities to test whether the animals maintain their personalities over large geographical scale, although the practical difficulties associated with these studies have hampered such tests. Here, we demonstrate for the first time consistency in disturbance tolerance behaviour in a long-distance migratory bird, using the common crane Grus grus as an ecological model species. Cranes that hatched in undisturbed habitats in Finland choose undisturbed migratory stop-over sites in Hungary, 1300-2000 km away from their breeding ground. This is remarkable, because these sites are not only separated by large distances, they also differ ecologically: the breeding sites are wooded bogs and subarctic tundra, whereas the migratory stop-over sites are temperate zone alkaline grasslands. The significance of our study goes beyond evolutionary biology and behavioural ecology: local effects on behaviour may carry over large distances, and this hitherto hidden implication of habitat selection needs to be incorporated into conservation planning. 相似文献
97.
Evelin Ramóna Péli Nie Lei Tamás Pócs Zsanett Laufer Stefan Porembski Zoltán Tuba 《Central European Journal of Biology》2011,6(5):838-849
In our present studies, the recovery of photosynthetic activity after rehydration was demonstrated. We measured chlorophyll
fluorescence, CO2 gas exchange and the pigment composition in the previously long-term air-dried cryptogamic inselberg crusts collected from
two tropical areas. The cryptobiotic crusts were collected from different localities on similar ecological and climatic conditions
from extreme habitats of inselbergs (outcrops). These inselbergs are characterized by a dry microclimate and are covered by
scarce soil. We found that the ecophysiological responses of both cryptogamic inselberg crusts showed an extremely high degree
of desiccation-tolerance due to the fast and full recovery during rehydration. The photosynthetic activity of the cryptobiotic
crusts were restored and regained within 15 and 40 min, respectively, after rehydration. Photosynthetic activity of the crusts
was retained at all applied light intensities when enough water was available, however the degree of the recovery was different
between the crusts. Photosynthetic pigment contents were strongly and positively correlated with water content. Our results
indicated that tropical desiccation-tolerant cryptogamic crusts found on inselberg rock surfaces have CO2 fixation ability in the range of cyanobacteria and lichens, suggesting that at a global scale they can assimilate CO2 in a significant amount. 相似文献
98.
Effect of S-methylmethionine on the photosynthesis in maize at different chilling temperatures 总被引:1,自引:0,他引:1
Eszter Kósa Dóra Szegő Eszter Horváth Ilona Rácz Zoltán Szigeti Demeter Lásztity Emil Páldi 《Central European Journal of Biology》2011,6(1):75-83
The effect of the natural compound S-methylmethionine (SMM) on the functioning of the photosynthetic apparatus, the efficiency
of photosynthesis and the synthesis of stress-induced phenoloids and anthocyanins involved in defence was investigated in
young maize plants exposed to moderate and severe chilling stress. Damage to PSII was observed as a reduction in the value
of variable fluorescence (Fv/Fm) which could be detected even after few hours of mild chilling stress. At temperatures below
10°C, the reduction in Fv/Fm was more pronounced. Changes in the value of net photosynthesis exhibited a similar tendency.
SMM has a moderating effect on this reduction and its protective effect was more pronounced under long-lasting chilling stress
and at the lowest temperatures. Monitoring of fluorescence intensities and ratios correlated with the levels of stress defence
compounds. The fluorescence intensities were found to increase over the course of chilling stress in response to SMM, with
the highest values being recorded in plants exposed to the longest period of stress. A similar tendency was observed for the
quantity of anthocyanins. The results confirm the complex role of SMM, which is manifested both in preserving the ability
of the photosynthetic apparatus to function and in stimulating the synthesis of metabolites involved in stress defence. 相似文献
99.
Genome sequences of vertebrate model organisms are becoming available, fuelling the next challenging phase of research: annotating all of the genes with functional information. The functional annotation of all of the approximately 35 000 genes in mammals will undoubtedly require complementing the technologies of forward and reverse genetics in mutagenesis screens. Two recent articles report on the construction of retrotransposable elements that efficiently 'jump' in mammalian cells. These new elements hold great promise as useful vectors for insertional mutagenesis screens in the mouse. 相似文献
100.
The genetic potential of the red and fallow deer populations in Hungary is well known. Conserving the variability in this excellent genetic material for game preservation is one of our most important task. The aim of the present pilot study was to test the logistical steps of a sperm processing and storing system in which deer sperm can be stored at a level that meets quality standards accepted for domestic animals. Moreover, two different semen extenders, commercially used for freezing bull semen, were compared from the viewpoint of applicability to freeze fallow deer sperm. Sperm was collected from epididymes of eight red stags (Cervus elaphus hippelaphus) and six fallow bucks (Dama dama) during the rutting season. Red deer samples were washed in Triladyl extender, while fallow deer samples were split and processed in Triladyl or Bioxcell extender. In the samples, which had a shorter time interval between the death of the animal and the sperm collection, the percentage of viable spermatozoa with intact acrosome was typically higher. 相似文献