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51.
Miriam Nannette Ebert Gabriele Beyer-Sehlmeyer Ute Monika Liegibel Tanja Kautenburger Thomas Walter Becker Beatrice Louise Pool-Zobel 《Nutrition and cancer》2013,65(1-2):156-164
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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54.
Tanja H. Geelen John W. Rossen Antoine M. Beerens Linda Poort Servaas A. Morré Wilma S. Ritmeester Harry E. van Kruchten Masja M. van de Pas Paul H.M. Savelkoul 《Diagnostic microbiology and infectious disease》2013
A prospective, multicenter trial was designed to compare the performance characteristics of the cobas® 4800 (Roche Diagnostics, Indianapolis, IN, USA) and m2000 real-time™ (Abbott Molecular Inc., Des Plaines, IL, USA) assays for detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) in rectal and self-collected vaginal swabs. Rectal (n = 234) or self-collected vaginal swabs (n = 687) were obtained from consenting individuals visiting their general practitioners, dermatologists, gynecologists, sexually transmitted disease clinics, or family planning centers from May 2010 to February 2011. High concordance rates (≥96%) were observed between the cobas® 4800 and m2000 real-time™ assays for CT/NG detection in both rectal and self-collected vaginal swabs. The performance profiles confirm the usefulness of both kinds of swab types for CT and NG detection using described nucleic acid amplification tests assays. Based on this study, rectal and self-collected vaginal swabs offer a noninvasive alternative, which may improve screening for CT and NG infections. 相似文献
55.
Multiple chromosomal regions and polymorphisms of several candidate genes have been linked to or associated with atopic diseases (hayfever, asthma, allergic eczema and rhinitis). In this mini-review, we present data demonstrating that the genetic regulation of the inflammatory response makes a major contribution to the risk of atopy. These data also suggest that the quantity (or quality) of the inflammation affects the priming phase of atopy, i.e., that induced by allergens or infectious agents in early childhood. 相似文献
56.
Hiromura K Monkawa T Petermann AT Durvasula RV Shankland SJ 《Kidney international》2002,61(4):1312-1321
BACKGROUND: Elucidating the mechanisms of apoptosis is important for understanding the molecular mechanisms underlying glomerular disease. The phosphatidylinositol 3 kinase (PI3-kinase)/Akt pathway is essential for survival signaling in non-renal cells. However, little is known about the anti-apoptotic effect of insulin and the role of the PI3-kinase/Akt pathway in mesangial cells (MC) apoptosis. METHODS: Apoptosis was induced in wild type, p27Kip1 (p27) -/- and p21Cip1/Waf1 (p21) -/- mouse MC by survival factor withdrawal, actinomycin D, ultraviolet (UV)-B irradiation and cycloheximide in the presence or absence of insulin (1 micromol/L) or insulin-like growth factor-I (IGF-I; 100 ng/mL). The activation and levels of Akt, extracellular signal regulated kinase (ERK) and specific cell cycle proteins were determined by Western blot analysis. RESULTS: Insulin and IGF-I inhibited wild-type MC apoptosis induced by survival factor withdrawal, actinomycin D, ultraviolet-B irradiation and cycloheximide and in p27 -/- MC when apoptosis was induced by survival factor withdrawal. Akt was activated by insulin and IGF-I during apoptosis. Blocking PI3-kinase with LY294002 reduced Akt activation and abrogated the anti-apoptotic effect of insulin. ERK was activated during apoptosis and blocking ERK activation with U0126 or PD98059 partially rescued MC from apoptosis. Moreover, insulin also suppressed ERK activation during apoptosis. Our results also showed that the CDK-inhibitor p21 was increased by insulin and that p21 up-regulation was PI3-kinase/Akt pathway dependent. Furthermore, p21 -/- MC apoptosis induced by survival factor withdrawal was not rescued by insulin in contrast to the wild-type and p27 -/- MC. These data suggest that p21 may have a critical role in the anti-apoptotic effect of insulin. CONCLUSIONS: Insulin is a potent survival factor for MC in response to a number of different apoptotic triggers, and this effect is mediated through the PI3-kinase/Akt pathway. Moreover, ERK and p21 may be involved in anti-apoptotic effect of insulin in MC. 相似文献
57.
Florian Rudolf Fritzsche MD Tanja Reineke MD Lars Morawietz MD Glen Kristiansen MD Manfred Dietel MD Daniel Fink MD Christoph Rageth MD Christoph Honegger MD Rosmarie Caduff MD Holger Moch MD Zsuzsanna Varga MD 《Annals of surgical oncology》2010,17(11):2892-2898
Background
Recommendations for intraoperative and postoperative breast sentinel lymph node (SLN) processing differ widely. Micrometastases and isolated tumor cells (ITC) have recently been proposed as prognostically and therapeutically relevant. We compared 3 SLN protocols with regard to intraoperative and postoperative diagnosis.Materials and Methods
SLN in cohort I (270 patients) were intraoperatively assessed by stereomicroscopy. Intraoperative frozen section (IFS) was used only in stereomicroscopically suspicious SLN. In cohort II (197 patients), all SLN were examined with only 1 IFS. Final SLN workup in cohorts I and II consisted of complete step sectioning with immunohistochemistry. In cohort III (268 patients) 2 or more IFS were performed followed by 3 step sections and immunohistochemistry.Results
pN1 stages were significantly higher in cohorts I and II (33.3% and 34.0% respectively) than in cohort III (24.6%). Intraoperative false negativity for the detection of metastases (pN1) ranged from 54.4% (cohort I) and 35.8% (cohort II) to 21.2% (cohort III). In contrast, ITC were detected significantly more frequently in cohort I (9.3%) and cohort II (14.7%) than in cohort III (1.9%).Conclusions
Higher rates of SLN metastases and ITC in cohort I/II compared to cohort III suggest that IFS may result in tissue loss thus increasing the risk of missing metastases. Sparse IFS but complete postoperative SLN workup with step sectioning and immunohistochemistry provides more accurate information regarding minimal disease in SLN, but often results in delayed axillary lymph node dissection. This is important for preoperative patient information and recommendations in SLN processing protocols. 相似文献58.
Validation of the diagnostic value of NMP22 BladderChek test as a marker for bladder cancer by photodynamic diagnosis 总被引:2,自引:0,他引:2
Tritschler S Scharf S Karl A Tilki D Knuechel R Hartmann A Stief CG Zaak D 《European urology》2007,51(2):403-7; discussion 407-8
OBJECTIVES: The aim of the present study was to validate the sensitivity and specificity of the new "point-of-care" NMP22 BladderChek test compared to photodynamic diagnosis (PDD). METHODS: Voided urine samples from 100 patients with suspicion of bladder cancer were collected to perform the NMP22 BladderChek test and voided urinary cytology. The nuclear matrix protein 22 (NMP22) levels were measured by a lateral flow immunochromatographic qualitative assay, using 10 U/ml as the cut-off value. Subsequently patients underwent PDD, using 5-aminolevulinic acid or hexyl-aminolevulinate; previous bladder washings for cytology were collected. Sensitivity and specificity of the NMP22 BladderChek test were compared with cytology and PDD. RESULTS: Forty of the 100 patients had urothelial malignancies (22 pTa, 4 pT1, 3 pT2, 9 carcinoma in situ, 2 pTx; 16 G1, 6 G2, 18 G3). The sensitivity was 65% for the NMP22 BladderChek test, 44% for voided cytology, 75% for washing cytology, and 93% for PDD. Specificity rates were 40%, 78%, 62%, and 43%, respectively. Positive predictive values were 0.42, 0.58, 0.53, and 0.52 and the negative predictive values 0.63, 0.68, 0.82, and 0.9, respectively. CONCLUSIONS: The results demonstrate that the NMP22 BladderChek is an easily applied test, giving diagnostic findings within 30 min. However, validated by the highly sensitive PDD, the NMP22 BladderChek test demonstrates poor specificity and sensitivity and, therefore, cannot be recommended for screening or surveillance in daily clinical routine use. Further studies with careful patient selection are necessary to identify the patient population that might benefit from the NMP22 BladderChek test. 相似文献
59.
Hankemeier S van Griensven M Ezechieli M Barkhausen T Austin M Jagodzinski M Meller R Bosch U Krettek C Zeichen J 《Archives of orthopaedic and trauma surgery》2007,127(9):815-821
Introduction The original complex structure and mechanical properties are not fully restored after ligament and tendon injuries. Due to
their high proliferation rate and differentiation potential, Bone Marrow Stromal Cells (BMSC) are considered to be an ideal
cell source for tissue engineering to optimize the healing process. Ideal matrices for tissue engineering of ligaments and
tendons should allow for homogenous cell seeding and offer sufficient stability.
Material and methods A mixture of human BMSC and liquid fibrin glue was injected into a standardized full-thickness window defect of the patellar
tendon of immunodeficient rats (BMSC group). The histology of the tissue was analysed 10 and 20 days postoperatively and compared
to four control groups. These groups consisted of a cohort with a mixture of human fibroblasts and fibrin glue, fibrin glue
without cells, a defect group without treatment, and a group with uninjured patellar tendon tissue.
Results Tendon defects in the BMSC group revealed dense collagen fibres and spindle-shaped cells, which were mainly orientated along
the loading axis. Histologic sections of the control groups, especially of untreated defects and of defects filled with fibrin
glue only, showed irregular patterns of cell distribution, irregular formed cell nucleoli and less tissue maturation. Compared
to healthy tendon tissue, higher numbers of cells and less intense matrix staining was observed in the BMSC group. No ectopic
bone or cartilage formation was observed in any specimen.
Conclusions Injection of human BMSC in a fibrin glue matrix appears to lead to more mature tissue formation with more regular patterns
of cell distribution. Advantages of this “in-vivo” tissue engineering approach are a homogenous cell-matrix mixture in a well-known
and approved biological matrix, and simple, minimally-invasive application by injection. 相似文献
60.
Adult outcomes of attention deficit hyperactivity disorder and conduct disorder: are the risks independent or additive? 总被引:1,自引:0,他引:1
Tracy D Gunter Stephan Arndt Kristin Riggins-Caspers Gloria Wenman Remi J Cadoret 《Annals of clinical psychiatry》2006,18(4):233-237
METHODS: Data were obtained from a longitudinal study sample of 754 adoptees and categorized based on review of the available adoption agency, medical, and psychiatric records of the biological parents. Categorical data were analyzed using chi2 or Fisher's exact tests, as appropriate. Logistic regression analyses were used to assess the relative contribution of variables. RESULTS: There was not a statistically significant difference in the frequency or type of self-reported adult disruptive behavior, arrests, jail stays, felony arrests, or frequency of conduct disorder (CD) when inattentiveness, impulsivity, and hyperactivity were analyzed individually. The contributions of attention deficit hyperactivity disorder (ADHD) were independent and no additional increased risk for future illegal behavior was conferred by the combination of the disorders. While the effect of CD on illegal behavior was correlated with substance abuse and dependence, ADHD continued to be a significant contributor after controlling for substance abuse and dependence. CONCLUSIONS: Data indicated that ADHD and CD are related but different disorders conferring risk for adult illegal behavior or arrest. In this sample, inattention was the most common domain impaired among those with ADHD, followed closely by hyperactivity, with impulsivity reported least often among those endorsing symptoms of ADHD. 相似文献