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Butyrate, one of the major products of gut fermentation, is known to inhibit proliferation, induce apoptosis and differentiation, and increase phase II enzyme activities in tumor cells, whereas little information is available on protective effects in less-transformed colon cells. The aim of this study was to investigate whether the chemoprotective mechanism of glutathione S-transferase (GST) induction by butyrate could also play a role in earlier stages of colon carcinogenesis and whether chemoresistance of cells toward the endogenous genotoxic risk factor 4-hydroxy-2-nonenal (HNE) could be a consequence of butyrate treatment. As cell models, we used the human tumor cell lines HT29 and HT29 clone 19A, a differentiated subclone with properties resembling primary colon cells. We determined the expression of GSTP1 protein (enzyme-linked immunosorbent assay), the major GST in HT29, GSTP1 mRNA (Northern blotting), GST activity, intracellular glutathione, and total protein. The genotoxic impact of HNE (100-200 μM) was compared in butyrate-treated and nontreated cells using single-cell microgel electrophoresis. Our results show that GSTP1 mRNA, GSTP1 protein, GST activity, and total protein were increased (1.2- to 2.5-fold) and glutathione levels were maintained after 24- 72 h of incubation with 4 mM butyrate. Moreover, a marked reduction of HNE-induced genotoxicity was caused by preincubation with butyrate. Butyrate also induced the phosphorylation of extracellular signal-regulated kinases (ERK1/2, Western blotting) after 5-30 min, which indicates a regulation of GST expression by this signal pathway. Most effects were greater in HT29 parent cells than in clone cells. In conclusion, butyrate enhances expression of GST and other proteins in both cell lines, which leads to an enhanced chemoprotection, reducing the impact of HNE genotoxicity. Thus butyrate could play a role in early and later stages of cancer prevention by reducing exposure to relevant risk factors.  相似文献   
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The aim of this study was to assess the levels of oxidative, inflammatory, and fibrinolytic biomarkers as well as DNA strand breakage in hypercholesterolemic subjects. Fasting glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, uric acid, total protein, albumin, apolipoprotein (Apo) A, Apo B, advanced oxidation protein products (AOPP), increased ischemia-modified albumin (IMA), ―SH, NOx, IL-6, and D-dimer levels were assessed, and DNA strand breakage was evaluated using comet assay in 38 patients with hypercholesterolemia and 20 healthy controls. Total cholesterol, triglycerides, LDL cholesterol, Apo A, Apo B, AOPP, IMA, IL-6, and D-dimer concentrations were significantly higher in subjects with hypercholesterolemia. However, NOx and plasma ―SH group concentrations were lower in hypercholesterolemic subjects, while no significant differences were observed with respect to DNA strand breakage between the two groups. Hypercholesterolemia is related to oxidative stress and inflammation. Accordingly, AOPP concentration was higher in subjects with hypercholesterolemia, and we speculate that AOPP can reflect the enhancement of protein oxidation and inflammation.  相似文献   
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Die Anaesthesiologie - Der Postpunktionskopfschmerz („postdural puncture headache“, PDPH) zählt zu den wesentlichen Komplikationen der peripartalen neuroaxialen Analgesie. Als...  相似文献   
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Sickle cell anaemia (SCA) is the consequence of abnormal haemoglobin production due to an inherited point mutation in the β‐globin gene. The resulting haemoglobin tetramer is poorly soluble when deoxygenated, and when this is prolonged, intracellular gelation of sickle haemoglobin occurs, followed by haemoglobin polymerisation. If many cycles of sickling and unsickling occur, the red cell membrane will be disrupted leading to haemolysis and vaso‐occlusive events. Recent studies have also shown that leucocyte adhesion molecules and nitric oxide (NO) depletion are involved in endothelial damage. New insights in SCA pathophysiology and vascular biology have shown that cell‐derived microparticle (MP) generation is also involved in the vaso‐occlusion. Endothelial damage is perpetuated by impaired production or increased consumption of protective modulators such as protein C, protein S and NO. New therapeutic interventions should address these aspects of SCA pathogenesis. To date, the only US‐FDA‐approved therapy to prevent painful vaso‐occulsive episodes is hydroxyurea that reduces haemoglobin polymerisation in sickle cells by increasing the production of foetal haemoglobin and L‐glutamine. However, several new drugs have been tested in the last years in randomised clinical trials. We here report an update on the current status of knowledge on SCA.  相似文献   
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Purpose: The purpose of this study was to assess the sensitivity and responsiveness of the Segmental Assessment of Trunk Control (SATCo) for evaluating trunk control in children with spinal cord injury (SCI) receiving activity-based locomotor training (AB-LT).

Methods: Prospective study of nine outcomes for consecutively enrolled children in outpatient AB-LT. To evaluate sensitivity to change, linear-mixed models were constructed and adjusted for covariates: age at and time since SCI. To evaluate responsiveness, standardized response means and 95% confidence intervals were estimated per outcome.

Results: SATCo scores increased significantly (p < 0.05) regardless of chronicity, initial score, and injury level. The SATCo was the most responsive measure and the only outcome demonstrating a large effect size after 3 months of therapy.

Conclusions: Children with SCI receiving AB-LT improved trunk control regardless of chronicity, initial impairment, or prior experience. SATCo sensitivity and responsiveness support its usefulness in measuring trunk control in children with SCI.  相似文献   

67.
The aim of this study was (a) to examine the anatomy of the sural nerve (SN) in a sample of 30 patients and (b) to analyze the incidence of different origins of the SN, and the distance of the SN from planned arthroscopic portals. An ultrasound (USG) examination of the SN was performed bilaterally on thirty healthy patients with no history of surgery or trauma of the lower limb. The SNs were classified into six main types of pattern, with an additional category for new and unclassified types. Each of Types 1 and 3 had two subdivisions. The distances from the superior border of the calcaneal tuberosity to the three simulated arthroscopy portal sites (Z1, Z1.5, Z2) to the SN were measured. A total of 30 patients (n = 60 limbs) with an average age of 27 ± 7.5 years were examined and the SN was visualized in all cases. The most common origin was Type 3A, accounting for 30% of limbs. Type 2 was the second most common seen in 18.3%. The distances of the SN from arthroscopic portal placement sites above the lateral malleolus were 2.07 ± 0.39 cm at the Z1 portal, 2.15 ± 0.38 cm at Z1.5, and 2.28 ± 0.33 cm at Z2. The variability in the anatomy of the SN warrants the use of USG to locate it accurately, thus preventing iatrogenic injury when portals are placed for arthroscopy, improving proper administration of anesthesia, and helping to localize the nerve for graft harvesting. Clin. Anat. 31:450–455, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
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