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31.
M. Białecka A. Jurewicz P. Cięszczyk A. Machoy-Mokrzyńska M. Kurzawski K. Leźnicka V. Dziedziejko K. Safranow M. Droździk A. Bohatyrewicz 《Russian Journal of Genetics》2016,52(5):539-542
Pain in patients with hip osteoarthritis appears long before surgery, and requires effective management as it affects patient comfort and daily activities. Therefore, the search for factors influencing response rate to analgesics is mandatory. In recent years, increasing attention has been paid to genetic factors underlying pain threshold and treatment efficacy. Polymorphic gene of catechol-oxide-methyltransferase (COMT) is a candidate gene associated with pain pathology and treatment response. The aim of the study was to evaluate association between the COMT rs4680:G>A polymorphism and demand for analgesics in patients subjected to elective hip replacement. The study included 196 patients after hip replacement surgery. Opioid demand was recorded and analgesic efficacy was scored using a four-level verbal pain intensity scale. COMT rs4680:G>A polymorphism was analysed by PCR-RFLP method. The studied COMT genotypes did not influence opioid administration in the studied patients from the day of surgery till day 6 afterwards. The distribution of the COMT rs4680:G>A in the studied subjects was as follows: GA—52.04%, AA—23.98% and GG—23.98%. It can be concluded that the COMT rs4680:G>A polymorphism is not associated with opioid demand in patients after elective hip replacement. 相似文献
32.
M. St?pien-S?odkowska K. Ficek J. Eider A. Leońska-Duniec A. Maciejewska-Kar?owska M. Sawczuk A. Zar?bska Z. Jastrz?bski A. Grenda K. Kotarska P. Ci?szczyk 《Biology of sport / Institute of Sport》2013,30(1):57-60
Objectives
The aim of this study was to examine the association of +1245G/T polymorphisms in the COL1A1 gene with ACL ruptures in Polish male recreational skiers in a case-control study.Methods
A total of 138 male recreational skiers with surgically diagnosed primary ACL ruptures, all of whom qualified for ligament reconstruction, were recruited for this study. The control group comprised 183 apparently healthy male skiers with a comparable level of exposure to ACL injury, none of whom had any self-reported history of ligament or tendon injury. DNA samples extracted from the oral epithelial cells were genotyped for the +1245G/T polymorphisms using real-time PCR method.Results
Genotype distributions among cases and controls conformed to Hardy-Weinberg equilibrium (p = 0.2469 and p = 0.33, respectively). There was a significant difference in the genotype distribution between skiers and controls (p = 0.045, Fisher''s exact test). There was no statistical difference in allele distribution: OR 1.43 (0.91-2.25), p = 0.101 (two-sided Fisher''s exact test).Conclusions
The risk of ACL ruptures was around 1.43 times lower in carriers of a minor allele G as compared to carriers of the allele T. 相似文献33.
Hui‐Hsu Gavin Tsai Jian‐Bin Lee Sheng‐Shiuan Tseng Xiao‐An Pan Yuan‐Ci Shih 《Proteins》2010,78(8):1909-1925
The mechanisms of interfacial folding and membrane insertion of the Alzheimer's amyloid‐β fragment Aβ(25–35) and its less toxic mutant, N27A‐Aβ(25–35) and more toxic mutant, M35A‐Aβ(25–35), are investigated using replica–exchange molecular dynamics in an implicit water‐membrane environment. This study simulates the processes of interfacial folding and membrane insertion in a spontaneous fashion to identify their general mechanisms. Aβ(25–35) and N27A‐Aβ(25–35) peptides share similar mechanisms: the peptides are first located in the membrane hydrophilic region where their C‐terminal residues form helical structures. The peptides attempt to insert themselves into the membrane hydrophobic region using the C‐terminal or central hydrophobic residues. A small portion of peptides can successfully enter the membrane's hydrophobic core, led by their C‐terminal residues, through the formation of continuous helical structures. No detectable amount of M35A‐Aβ(25–35) peptides appeared to enter the membrane's hydrophobic core. The three studied peptides share a similar helical structure for their C‐terminal five residues, and these residues mainly buried within the membrane's hydrophobic region. In contrast, their N‐terminal properties are markedly different. With respect to the Aβ(25–35), the N27A‐Aβ(25–35) forms a more structured helix and is buried deeper within the membrane, which may result in a lower degree of aggregation and a lower neurotoxicity; in contrast, the less structured and more water‐exposed M35A‐Aβ(25–35) is prone to aggregation and has a higher neurotoxicity. Understanding the mechanisms of Aβ peptide interfacial folding and membrane insertion will provide new insights into the mechanisms of neurodegradation and may give structure‐based clues for rational drug design preventing amyloid associated diseases. Proteins 2010. © 2010 Wiley‐Liss, Inc. 相似文献
34.
Dunwei Ci Dong Jiang Bernd Wollenweber Tingbo Dai Qi Jing Weixing Cao 《Acta Physiologiae Plantarum》2010,32(2):365-373
Seedlings of wheat (Triticum aestivum L.) cultivars Jing 411, Jinmai 30 and Yangmai 10 were exposed to 0, 10, 20, 30, 40 or 50 μM of CdCl2 in a solution culture experiment. The effects of cadmium (Cd) stress on wheat growth, leaf photon energy conversion, gas
exchange, and Cd accumulation in wheat seedlings were investigated. Gas exchange was monitored at 3, 9, 24 days after treatment
(DAT). Growth parameters, chlorophyll content, leaf chlorophyll fluorescence, and Cd concentration in shoot and root were
measured at 24 DAT. Seedling growth, gas exchange, chlorophyll content, chlorophyll fluorescence parameters were generally
depressed by Cd stress, especially under the high Cd concentrations. Cd concentration and accumulation in both shoots and
roots increased with increasing external Cd concentrations. Relationships between corrected parameters of growth, photosynthesis
and fluorescence and corrected Cd concentrations in shoots and roots could be explained by the regression model Y = K/(1 + exp(a + bX)). Jing 411 was found to be Cd tolerant considering parameters of chlorophyll content, photosynthesis and chlorophyll fluorescence
in which less Cd translocation was from roots into shoots. The high Cd concentrations were in shoots and roots in Yangmai
10 which has been found to be a relative Cd tolerant cultivar in terms of most growth parameters. 相似文献
35.
Autophagy is a cellular process in degradation of long-lived proteins and organelles in the cytosol for maintaining cellular
homeostasis, which has been linked to a wide range of human health and disease states, including viral infection. The viral
infected cells exhibit a complicated cross-talking between autophagy and virus. It has been shown that autophagy interacts
with both adaptive and innate immunity. For adaptive immunity, viral antigens can be processed in autophagosomes by acidic
proteases before major histocompatibility complex (MHC) class II presentation. For innate immunity, autophagy may assist in
the delivery of viral nucleic acids to endosomal TLRs and also functions as a part of the TLR-or-PKR-downstream responses.
Autophagy was also reported to suppress the magnitude of host innate antiviral immunity in certain cases. On the other hand,
viruses has evolved many strategies to combat or utilize the host autophagy for their own benefit. In this review we discussed
recent advances toward clarifying the cross-talking between autophagy and viral infection in mammalian cells. 相似文献
36.
37.
The aim of this study is to investigate the influence of extractives on the yield and composition of oil obtained from biomass samples (Artemisia ordosica, corn stalk and wheat straw). Direct deoxy-liquefaction experiments of original and extracted biomass were performed at certain temperature in a stainless steel tubular reactor. Benzene-alcohol solvent extraction had significant effect on the product distribution of biomass, especially on the yield and composition of the product oils. The oil yield of original biomass and alkane content in the oil were in the range of 5.44-9.27% and 8.23-23.64%, while decreased to 3.83-4.45% and 1.07-6.03% for the extracted biomass. This study concludes that most of alkanes in the oil mainly derive from the decomposition of triglyceride and hydrocarbon existed in the extractives of biomass. The results might be helpful to study the origin of alkanes and benzene derivatives in the oil obtained from biomass via direct deoxy-liquefaction. 相似文献
38.
39.
Automatic text summarization for a biomedical concept can help researchers to get the key points of a certain topic from large amount of biomedical literature efficiently. In this paper, we present a method for generating text summary for a given biomedical concept, e.g., H1N1 disease, from multiple documents based on semantic relation extraction. Our approach includes three stages: 1) We extract semantic relations in each sentence using the semantic knowledge representation tool SemRep. 2) We develop a relation-level retrieval method to select the relations most relevant to each query concept and visualize them in a graphic representation. 3) For relations in the relevant set, we extract informative sentences that can interpret them from the document collection to generate text summary using an information retrieval based method. Our major focus in this work is to investigate the contribution of semantic relation extraction to the task of biomedical text summarization. The experimental results on summarization for a set of diseases show that the introduction of semantic knowledge improves the performance and our results are better than the MEAD system, a well-known tool for text summarization. 相似文献
40.
Effect of high nitrate concentration on PHB storage in sequencing batch reactor under anoxic conditions 总被引:1,自引:0,他引:1
The study investigated effect of high influent nitrate concentration on poly-beta-hydroxybutyrate, (PHB), storage in a sequencing batch reactor, (SBR), under anoxic conditions. Acetate was fed as pulse during anoxic phase, sustained with external nitrate feeding. SBR operation involved three runs at steady state with COD/N ratios of 3.84, 2.93 and 1.54 gCOD/gN, where external nitrate concentrations gradually increased from 50 mg N/l to 114 mg N/l and 226 mg N/l, in 1st, 2nd and 3rd runs, respectively. In 1st run, acetate was fully converted into PHB with the storage yield value of 0.57-0.59 gCOD/gCOD, calculated both in terms of PHB formation and NO(X) utilization, confirming storage was the sole substrate utilization mechanism. In the following runs, PHB formation was reduced and the storage yield based on PHB dropped down to 0.40 and 0.33 gCOD/gCOD with increasing influent nitrate concentrations, indicating that higher portions of acetate were diverted to simultaneous direct growth. The observations suggested that nitrite accumulation detected at low COD/N ratios was responsible for inhibition of PHB storage. 相似文献