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331.
Biological fluid sample collection often includes the risk of blood contamination that may alter the proteomic profile of biological fluid. In proteomics studies, exclusion of contaminated samples is usually based on visual inspection and counting of red blood cells in the sample; analysis of specific blood derived proteins is less used. To fill the gap, we developed a fast and sensitive method for ascertainment of blood contamination in crude biological fluids, based on specific blood-derived protein, hemoglobin detection by MALDI-TOF MS. The MALDI-TOF MS based method allows detection of trace hemoglobin with the detection limit of 0.12 nM. UV-spectrometry, which was used as reference method, was found to be less sensitive. The main advantages of the presented method are that it is fast, effective, sensitive, requires very small sample amount and can be applied for detection of blood contamination in various biological fluids collected for proteomics studies. Method applicability was tested on human cerebrospinal and follicular fluid, which proteomes generally do not contain hemoglobin, however, which possess high risk for blood contamination. Present method successfully detected the blood contamination in 12 % of cerebrospinal fluid and 24 % of follicular fluid samples. High percentage of contaminated samples accentuates the need for initial inspection of proteomic samples to avoid incorrect results from blood proteome overlap.  相似文献   
332.
333.
Hedgehog signaling pathway activation has been implicated in the pathogenesis of NASH. Despite this concept, hedgehog pathway inhibitors have not been explored. Thus, we examined the effect of vismodegib, a hedgehog signaling pathway inhibitor, in a diet-induced model of NASH. C57BL/6 mice were placed on 3-month chow or FFC (high saturated fats, fructose, and cholesterol) diet. One week prior to sacrifice, mice were treated with vismodegib or vehicle. Mice fed the FFC diet developed significant steatosis, which was unchanged by vismodegib therapy. In contrast, vismodegib significantly attenuated FFC-induced liver injury as manifested by reduced serum ALT and hepatic TUNEL-positive cells. In line with the decreased apoptosis, vismodegib prevented FFC-induced strong upregulation of death receptor DR5 and its ligand TRAIL. In addition, FFC-fed mice, but not chow-fed animals, underwent significant liver injury and apoptosis following treatment with a DR5 agonist; however, this injury was prevented by pre-treatment with vismodegib. Consistent with a reduction in liver injury, vismodegib normalized FFC-induced markers of inflammation including mRNA for TNF-α, IL-1β, IL-6, monocyte chemotactic protein-1 and a variety of macrophage markers. Furthermore, vismodegib in FFC-fed mice abrogated indices of hepatic fibrogenesis. In conclusion, inhibition of hedgehog signaling with vismodegib appears to reduce TRAIL-mediated liver injury in a nutrient excess model of NASH, thereby attenuating hepatic inflammation and fibrosis. We speculate that hedgehog signaling inhibition may be salutary in human NASH.  相似文献   
334.
Morin has written a rich and valuable book. Its main aim is to isolate the factors involved in maintaining behavioural lineages over time, and to understand how these factors might interact. In doing so, it takes issue with the abstract and idealised models and arguments of dual-inheritance theorists, which are alleged in this account to rely on an overly simplistic notion of imitative learning. Morin’s book is full of ethnographic, anthropological, and psychological research, and there is much to commend in it. However, Morin’s arguments against the dual-inheritance theorists are less convincing when put under scrutiny, and his positive picture which includes appeals to ostensive communication, intrinsic appeal and cultural attraction has some difficulties. I argue that when we contrast dual-inheritance theorists and Morin, we find that there may be fewer differences and greater commonalities than Morin’s book might suggest.  相似文献   
335.
Xenotransplantation of organs from the large domestic species will only be successful if the donor animals have been genetically modified, in particular regarding the α-Gal epitope, certain human complements (CD55 and CD59) and/or H-transferase. This requires, among other things, major embryo-technological efforts, and the rate of success is still far from an acceptable level in the domestic species. It is currently poor, but the progress is very good. In this brief review certain embryo-technological problems will be addressed with the focus on the pig as potential organ donor. In addition, certain views of the Danish ad hoc Committee on Gene Technology on xenotransplantation will be presented in this context as they are supposed to mirror the concern and the views of the issues important for the public and each individual.  相似文献   
336.
Molecular tools were used to evaluate the hybrid status of a specimen with intermediate colour pattern between Halichoeres bivittatus and Halichoeres garnoti from Belize. Phylogenetic analyses of the two species, eight Halichoeres species from new and old world lineages and two outgroups showed that the study species are closely related and that H. garnoti is the maternal contributor to the putative hybrid specimen, based on partial mitochondrial COI data. Direct sequencing of Intron 1 of the nuclear ribosomal protein S7 identified H. bivittatus as sister to H. garnoti with the putative hybrid specimen in an intermediate position, due to heterozygosity at nucleotides alternatively fixed in the two putative parent species. This is consistent with the hybrid status of the specimen, with parental contributions from both H. garnoti and H. bivittatus. These results, combined with no evidence of introgression between the two parent species (based on the mtDNA and the single investigated nuclear marker) and the biogeography and ecology of these species suggests that this is a rare event with minimal evolutionary implications.  相似文献   
337.
Based on regional stakeholder preferences and planning guidelines as allocation criteria for SRC, this study aims at providing a transparent approach to evaluate multiple environmental effects and the regional significance of SRC systems. Using the example of two poplar SRC-systems (4-year rotation, 9-year rotation) the potential effects on ground water supply, wind erosion, and biodiversity aspects are evaluated in comparison to arable land for two selected municipalities in the district of Uelzen, Germany. Building on fuzzy membership functions and simple fuzzy-logic rules, the qualitative multi-criteria assessment is transparent and easily to adapt. This approach is transferable to other regions and spatial levels, since it derives from commonly available data and scientific evidence. Results show that implementation of SRC could provide multiple beneficial environmental effects, especially in areas with low landscape heterogeneity. The tools provided allow for a multi-criteria evaluation of environmental effects, and reveal the sensitivity to distinct allocation patterns. Physiographical conditions of the study area implicate a preference for mini-SRC systems. This is supported by smaller decline of annual deep percolation water compared to maxi-SRC. On average, decline in groundwater recharge of mini-SRC (92mm a−1) is comparable to irrigated arable land (80mm a−1), which is common practice in the study area. Currently, the utilization of beneficial environmental SRC effects is quite limited, since only 3 % of arable land is suitable for SRC implementation regarding farmers’ preferences for SRC allocation. Allocation preferences could however change substantially with increasing incentives for SRC, e.g., due to regional bioenergy schemes or “Greening” initiatives within the European Common Agricultural Policy, which is to be reformed by 2013.  相似文献   
338.

Background  

Infection with severe malaria in African children is associated with not only a high mortality but also a high risk of cognitive deficits. There is evidence that interventions done a few years after the illness are effective but nothing is known about those done immediately after the illness. We designed a study in which children who had suffered from severe malaria three months earlier were enrolled into a cognitive intervention program and assessed for the immediate benefit in cognitive, academic and behavioral outcomes.  相似文献   
339.
The relationship between the severity of dengue infection and allergy is still obscure. We conducted an electronic search across 12 databases for relevant articles reporting allergic symptoms, dengue infection, and dengue classification. These studies were categorized according to dengue severity and allergy symptoms, and a meta-analysis was performed by pooling the studies in each category. Among the included 57 articles, pruritus was the most common allergic sign followed by non-specified allergy and asthma(28.6%, 13%, and 6.5%, respectively). Despite the reported significant association of dengue with pruritus and total Ig E level(P \ 0.05), in comparison with non-dengue cases and healthy controls, there was no association between the different severe dengue group with pruritus, skin allergy, food allergy or asthma. However,removing the largest study revealed a significant association between asthma with dengue hemorrhagic fever(DHF) rather than dengue fever(DF). In comparison with DF, DHF was associated with Ig E positivity. Furthermore, specific-Ig E level was higher in secondary DF rather than primary DF. There was a possible association between allergy symptoms and dengue severity progression. Further studies are needed to clarify this association.  相似文献   
340.
Plodia interpunctella and Oryzaephilus surinamensis are found in food storehouses including dates and palm storages. The current study aimed to determine competition and overlap potentials of the two pests of date fruits. Time series models were used to study two species populations and logistic growth model to estimate the effect of density of the species. The results revealed the environmental capacities of O. surinamensis and P. interpunctella were 433 and 1610 (maximum number per 20 g), respectively, and the population growth rates (r) were 1.2 and 1.3, respectively. Ecological balances of the two species were close to each other from the first to the third week. The population of O. surinamensis decreased in the fourth week of the competition. The highest population balance of the two species was in the 14th week. The potential of exploitable ecological niches (eij) and the amount of non-exploited ecological niches by any species (zij) for O. surinamensis was higher than for P. interpunctella from the 8th week untill the end of sampling period. The overlap of ecological niches in the two species (D) ranged from 0.94 to 1, indicating a complete overlap of temporal activity in the two populations on date palm. The current results of this study can be used by integrated pest management specialists. Information over the effects of species competition on population dynamics and their coexistence can be used to predict population status and to adopt simple pest control methods.  相似文献   
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