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71.
Wide Dynamic Range (WDR) neurons in the spinal cord receive inputs from the contralateral side that, under normal conditions, are ineffective in generating an active response. These inputs are effective when the target WDRs change their excitability conditions. To further reveal the mechanisms supporting this effectiveness shift, we investigated the weight of the excitation of the contralateral neurons on the target WDR responses. In the circuit of presynaptic (sending) and postsynaptic (receiving) neurons in crossed spinal connections the fibres that form the presynaptic neurons impinge on postsynaptic neurons can be considered the final relay of this contralateral pathway. The enhancement of the presynaptic neuron excitability may thus modify the efficacy of the contralateral input. Pairs of neurons each on a side of the spinal cord, at the L5–L6 lumbar level were simultaneously recorded in intact, anaesthetized, paralysed rats. The excitatory aminoacid NMDA and strychnine, the antagonist of the inhibitory aminoacid glycine, were iontophoretically administrated to presynaptic neurons to increase their excitability. Before and during the drug administration, spontaneous and noxious-evoked activities of the neurons were analysed. During the iontophoresis of the two substances we found that noxious stimuli applied to the receptive field of presynaptic neurons activated up to 50% of the previously unresponsive postsynaptic neurons on the opposite side. Furthermore, the neurons on both sides of the spinal cord showed significantly increased spontaneous activity and amplified responses to ipsilateral noxious stimulation. These findings indicate that the contralateral input participates in the circuit dynamics of spinal nociceptive transmission, by modulating the excitability of the postsynaptic neurons. A possible functional role of such a nociceptive transmission circuit in neuronal sensitization following unilateral nerve injury is hypothesized.  相似文献   
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Sphagnum mosses serve as a unique habitat for microorganisms, which play an important role both for the host plants and the peatland ecosystems. The aim of the present study was to isolate endophytic bacteria from the tissues of Sphagnum mosses and to screen them for strains promising for further application in agricultural microbiology. About 50 samples of Sphagnum fallax (H. Klinggr.) H. Klinggr. and Sphagnum magellanicum Brid. were collected in the Austrian Alps and the Lenindgrad Region of Russia in 2009–2010. Endophytic bacteria were detected inside the moss plants using fluorescent in situ hybridization (FISH) followed by confocal laser scanning microscopy (CLSM). Altogether, 283 isolates were obtained by cultivation on the nutrient media. Examination of the isolates for the antagonistic activity revealed that more than 50% of them could suppress the growth of phytopathogenic and toxigenic fungi. More than 30% of isolates showed some antagonistic activity against microbial phytopathogens. The isolated strains could colonize crops and promote their growth. Molecular-genetic identification coupled with physiological/biochemical characterization showed that the dominant endophytic groups belonged to the genera Burkholderia, Pseudomonas, Flavobacterium, Serratia and Collimonas. The isolated endophytes were shown to be promising objects for the development of effective growth-promoting and protective microbiological preparations to be used in agriculture.  相似文献   
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Background: Lifestyle seems to play an important role in endometrial cancer mortality, but it remains unclear which biomarkers are involved. The aim of this study was to assess the extent of the association between lifestyle-related biomarkers and the survival of endometrial cancer patients. Methods: A sub-cohort of 242 endometrial cancer patients, from a population-based study of the more than 90,000 female participants of the Vorarlberg Health Monitoring and Promotion Programme, was followed for a median duration of twelve years. Besides age, tumour staging, and histology, also pre-diagnostic levels of body mass index, blood pressure, triglycerides, total cholesterol, glucose, gamma-glutamyltransferase (GGT), and serum uric acid were analysed in Cox proportional hazards regression models to estimate multivariate mortality risks. Results: During follow-up 89 deaths occurred of which 49 were cancer-related. Survival was associated with age, tumour stage, and histology. Of the biomarkers, log10-transformed GGT showed a large effect on cancer-related mortality (HR = 3.35, 95% CI 1.12–10.03), whereas the other parameters did not appear with significant effects after adjustment for the other factors. Conclusion: Elevated level of GGT, a lifestyle-related marker, was associated with poor survival among endometrial cancer patients.  相似文献   
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This study was focused on species of Peziza belonging to the “P. ammophila” complex, using both morphological and molecular approaches. Molecular and morphological analyses showed that several taxa are hidden under the name “ammophila” and, as a consequence, two additional species and one form are established: P. hellenica sp. nov., P. oceanica sp. nov. and P. ammophila f. megaspora f. nov. On the basis of the data that we have, these taxa seem to be related to some geographical areas; P. ammophila appears to be prevalent in northern, central and southern Europe, its f. megaspora is distributed in France and in the Netherlands, P. hellenica comes from Greece and P. oceanica from New Zealand. A cryptic species, not yet circumscribed satisfactorily, is described as P. deceptiva ad int. Moreover, the problem concerning the identification of P. ammophila is raised, the species is epitypified with a sequenced collection from Sicily (Italy) and a key to the species of the complex is provided.  相似文献   
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The acquisition of regulatory proteins is a means of blood‐borne pathogens to avoid destruction by the human complement. We recently showed that the gametes of the human malaria parasite Plasmodium falciparum bind factor H (FH) from the blood meal of the mosquito vector to assure successful sexual reproduction, which takes places in the mosquito midgut. While these findings provided a first glimpse of a complex mechanism used by Plasmodium to control the host immune attack, it is hitherto not known, how the pathogenic blood stages of the malaria parasite evade destruction by the human complement. We now show that the human complement system represents a severe threat for the replicating blood stages, particularly for the reinvading merozoites, with complement factor C3b accumulating on the surfaces of the intraerythrocytic schizonts as well as of free merozoites. C3b accumulation initiates terminal complement complex formation, in consequence resulting in blood stage lysis. To inactivate C3b, the parasites bind FH as well as related proteins FHL‐1 and CFHR‐1 to their surface, and FH binding is trypsin‐resistant. Schizonts acquire FH via two contact sites, which involve CCP modules 5 and 20. Blockage of FH‐mediated protection via anti‐FH antibodies results in significantly impaired blood stage replication, pointing to the plasmodial complement evasion machinery as a promising malaria vaccine target.  相似文献   
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Purinergic Signalling - Genetic variants involved in adenosine metabolism and its receptors were associated with increased risk for psychiatric disorders, including anxiety, depression, and...  相似文献   
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Probiotics and Antimicrobial Proteins - Hylak® forte is a postbiotic that inhibits the growth of pathogenic bacteria by reducing intestinal pH. It is assumed the potential presence of...  相似文献   
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