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排序方式: 共有379条查询结果,搜索用时 31 毫秒
31.
Christoph Schwarz Daniel A. Klaus Bianca Tudor Edith Fleischmann Thomas Wekerle Georg Roth Martin Bodingbauer Klaus Kaczirek 《PloS one》2015,10(10)
Background
Parenchymal transection represents a crucial step during liver surgery and many different techniques have been described so far. Stapler resection is supposed to be faster than CUSA resection. However, whether speed impacts on the inflammatory response in patients undergoing liver resection (LR) remains unclear.Materials and Methods
This is a randomized controlled trial including 40 patients undergoing anatomical LR. Primary endpoint was transection speed (cm2/min). Secondary endpoints included the perioperative change of pro- and anti-inflammatory cytokines, overall surgery duration, length of hospital stay, morbidity and mortality.Results
Mean transection speed was significantly higher in patients undergoing stapler hepatectomy compared to CUSA resection (CUSA: 1 (0.4) cm2/min vs. Stapler: 10.8 (6.1) cm2/min; p<0.0001). Analyzing the impact of surgery duration on inflammatory response revealed a significant correlation between IL-6 levels measured at the end of surgery and the overall length of surgery (p<0.0001, r = 0.6188). Patients undergoing CUSA LR had significantly higher increase of interleukin-6 (IL-6) after parenchymal transection compared to patients with stapler hepatectomy in the portal and hepatic veins, respectively (p = 0.028; p = 0.044). C-reactive protein levels on the first post-operative day were significantly lower in the stapler cohort (p = 0.010). There was a trend towards a reduced overall surgery time in patients with stapler LR, especially in the subgroup of patients undergoing minor hepatectomies (p = 0.020).Conclusions
Liver resection using staplers is fast, safe and suggests a diminished inflammatory response probably due to a decreased parenchymal transection time.Trial Registration
ClinicalTrials.gov NCT01785212 相似文献32.
33.
Madoka Koyanagi Julie A Kerns Linda Chung Yan Zhang Scott Brown Tudor Moldoveanu Harmit S Malik Mark Bix 《BMC evolutionary biology》2010,10(1):223
Background
Interleukin-4 (IL4) is a secreted immunoregulatory cytokine critically involved in host protection from parasitic helminths [1]. Reasoning that helminths may have evolved mechanisms to antagonize IL4 to maximize their dispersal, we explored mammalian IL4 evolution. 相似文献34.
Electric features of biological membranes are major determinants of the function and physiological manifestation of membrane-penetrating peptides, and such features are prone to be modulated by the properties of the surrounding aqueous medium. In this work, we demonstrate that pH plays crucial roles in modulating electric characteristics of zwitterionic-based artificial lipid membranes. The effect of pH on electrical properties of such membranes was probed by evaluating the transport properties of embedded alamethicin oligomers over a wide range of pH values (i.e., 0.65, 2.08, 2.94, 7 and 10.1). Our data strongly support the paradigm of a pH-dependent variation of the surface and membrane dipole potential which, in conjunction with possible lateral pressure effects within the lipid membrane, lead to a non-monotonic modulation of the electrical conductance of alamethicin oligomers. As expected, pH modulation of transport properties through the alamethicin oligomer is more visible for narrower pores (that is, the 1st conductive state) with slightly better cation selectivity as compared to larger oligomers. 相似文献
35.
The in vitro behaviour and patterns of colony formation of murine epithelial stem cells 总被引:1,自引:0,他引:1
OBJECTIVE: The mechanisms of renewal of skin and mucosal epithelia in vivo are associated with hierarchies of stem and amplifying cells organized in distinct spatial patterns. Stem and amplifying characteristics persist after isolation and growth of human keratinocytes in vitro but the pattern for murine keratinocytes has been less clear. MATERIALS AND METHODS: Murine keratinocytes were grown in low calcium media and examined for their patterns of colony morphologies. RESULTS: We consistently identified three types of colonies, one of which contains concentric zones of amplifying and differentiated cells surrounding a central zone of cells that have patterns of expression and behavioural characteristic of stem cells. This zonal organization facilitated analysis of stem cell formation and loss. Cells in the central stem cell zone undergo rapid symmetric divisions but expansion of this population is partially limited by their peripheral transition into amplifying cells. A striking feature of central zone cells is their enhanced apoptotic susceptibility and stem cell expansion limited by consistently high background rates of apoptosis. This occasionally reaches catastrophic levels with elimination of the entire central zone. CONCLUSION: In vitro amplification of stem cells for the generation of engineered tissue has tended to focus on control of asymmetric division but these findings suggest that development of mechanisms protecting stem cells from apoptotic changes are also likely to be of particular value. 相似文献
36.
Gealy EC Kerr BC Young RD Tudor D Hayes AJ Hughes CE Caterson B Quantock AJ Ralphs JR 《Histochemistry and cell biology》2007,128(6):551-555
Keratan sulphate (KS) proteoglycans (PGs) are key molecules in the connective tissue matrix of the cornea of the eye, where
they are believed to have functional roles in tissue organisation and transparency. Keratocan, is one of the three KS PGs
expressed in cornea, and is the only one that is primarily cornea-specific. Work with the developing chick has shown that
mRNA for keratocan is present in early corneal embryogenesis, but there is no evidence of protein synthesis and matrix deposition.
Here, we investigate the tissue distribution of keratocan in the developing chick cornea as it becomes compacted and transparent
in the later stages of development. Indirect immunofluorescence using a new monoclonal antibody (KER-1) which recognises a
protein epitope on the keratocan core protein demonstrated that keratocan was present at all stages investigated (E10–E18),
with distinct differences in localisation and organisation observed between early and later stages. Until E13, keratocan appeared
both cell-associated and in the stromal extracellular matrix, and was particularly concentrated in superficial tissue regions.
By E14 when the cornea begins to become transparent, keratocan was located in elongate arrays, presumably associated along
collagen fibrils in the stroma. This fibrillar label was still concentrated in the anterior stroma, and persisted through
E15–E18. Presumptive Bowman’s layer was evident as an unlabelled subepithelial zone at all stages. Thus, in embryonic chick
cornea, keratocan, in common with sulphated KS chains in the E12–E14 developmental period, exhibits a preferential distribution
in the anterior stroma. It undergoes a striking reorganisation of structure and distribution consistent with a role in relation
to stromal compaction and corneal transparency.
E. Claire Gealy and Briedgeen C. Kerr were joint first authors. 相似文献
37.
Matsuoka RL Chivatakarn O Badea TC Samuels IS Cahill H Katayama K Kumar SR Suto F Chédotal A Peachey NS Nathans J Yoshida Y Giger RJ Kolodkin AL 《Neuron》2011,71(3):460-473
In the vertebrate retina, neurites from distinct neuronal cell types are constrained within the plexiform layers, allowing for establishment of retinal lamination. However, the mechanisms by which retinal neurites are segregated within the inner or outer plexiform layers are not known. We find that the transmembrane semaphorins Sema5A and Sema5B constrain neurites from multiple retinal neuron subtypes within the inner plexiform layer (IPL). In Sema5A?/?; Sema5B?/? mice, retinal ganglion cells (RGCs) and amacrine and bipolar cells exhibit severe defects leading to neurite mistargeting into the outer portions of the retina. These targeting abnormalities are more prominent in the outer (OFF) layers of the IPL and result in functional defects in select RGC response properties. Sema5A and Sema5B inhibit retinal neurite outgrowth through PlexinA1 and PlexinA3 receptors both in vitro and in vivo. These findings define a set of ligands and receptors required for the establishment of inner retinal lamination and function. 相似文献
38.
Synesthesia is an unusual condition characterized by the over-binding of two or more features and the concomitant automatic and conscious experience of atypical, ancillary images or perceptions. Previous research suggests that synesthetes display enhanced modality-specific perceptual processing, but it remains unclear whether enhanced processing contributes to conscious awareness of color photisms. In three experiments, we investigated whether grapheme-color synesthesia is characterized by enhanced cortical excitability in primary visual cortex and the role played by this hyperexcitability in the expression of synesthesia. Using transcranial magnetic stimulation, we show that synesthetes display 3-fold lower phosphene thresholds than controls during stimulation of the primary visual cortex. We next used transcranial direct current stimulation to discriminate between two competing hypotheses of the role of hyperexcitability in the expression of synesthesia. We demonstrate that synesthesia can be selectively augmented with cathodal stimulation and attenuated with anodal stimulation of primary visual cortex. A control task revealed that the effect of the brain stimulation was specific to the experience of synesthesia. These results indicate that hyperexcitability acts as a source of noise in visual cortex that influences the availability of the neuronal signals underlying conscious awareness of synesthetic photisms. 相似文献
39.
40.
Tamayo N Liao L Goldberg M Powers D Tudor YY Yu V Wong LM Henkle B Middleton S Syed R Harvey T Jang G Hungate R Dominguez C 《Bioorganic & medicinal chemistry letters》2005,15(9):2409-2413
Novel potent trisubstituted pyridazine inhibitors of p38 MAP (mitogen activated protein) kinase are described that have activity in both cell-based assays of cytokine release and animal models of rheumatoid arthritis. They demonstrated potent inhibition of LPS-induced TNF-alpha production in mice and exhibited good efficacy in the rat collagen induced arthritis model. 相似文献