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51.
Valentín-Blasini L Sadowski MA Walden D Caltabiano L Needham LL Barr DB 《Journal of exposure analysis and environmental epidemiology》2005,15(6):509-523
We report population-based urinary concentrations of phytoestrogens stratified by age, sex, and composite racial/ethnic variables. We measured the isoflavones - genistein, daidzein, equol, and O-desmethylangolensin (O-DMA) - and the lignans - enterolactone and enterodiol - in approximately 2500 urine samples from individuals aged 6 years and older who participated in the National Health and Nutrition Examination Survey (NHANES) in 1999 and 2000. We detected all phytoestrogens in over 70% of the samples analyzed; enterolactone was detected in the highest concentrations, and daidzein was detected with the highest frequency. The geometric means for each phytoestrogen were as follows: genistein, 22.3 microg/g; daidzein, 68.6 microg/g; equol, 7.65 microg/g; O-DMA, 3.95 microg/g; enterolactone, 217 microg/g; and enterodiol, 24.3 microg/g creatinine. The 95th percentiles for each phytoestrogen were as follows: genistein, 380 microg/g; daidzein, 944 microg/g; equol, 50.3 microg/g; O-DMA, 217 microg/g; enterolactone, 2240 microg/g; and enterodiol, 240 microg/g creatinine. Multivariate analyses showed statistically significant differences among many of the demographic subgroups. Adolescents had higher concentrations of genistein and equol than adults. Non-Hispanic whites had higher concentrations of enterodiol and equol than Mexican Americans or non-Hispanic blacks. Non-Hispanic whites also had higher concentrations of enterolactone and O-DMA than Mexican Americans. Mexican Americans had higher concentrations of genistein than non-Hispanic blacks; however, the opposite was found for O-DMA. Determination of phytoestrogen exposure in the US population will help us to better understand phytoestrogen consumption in the US and will assist us in elucidating the potential role of phytoestrogens in protecting against cancer and heart disease. 相似文献
52.
Development of a wound infection after nasal reconstruction can place the entire reconstructive effort in jeopardy. The approach to management in these cases has traditionally entailed wound drainage, removal of involved graft material, and debridement of nonvital tissue. Following adequate wound healing, delayed reconstruction is then performed, with the final result often compromised in form and function.We present a case of a postoperative wound infection following reconstruction of a traumatic nasal deformity utilizing autologous cartilage grafts. Treatment consisted of hospitalization with administration of culture-specific parenteral antibiotics and continuous through-and-through antibiotic irrigation of the wound via an indwelling catheter. The infection was completely eradicated and all cartilage grafts were salvaged utilizing this technique. At 3 years postoperatively, the patient has maintained the shape and quality of her reconstruction, without evidence of recurrent infection. 相似文献
53.
MALT1 and the API2-MALT1 fusion act between CD40 and IKK and confer NF-kappa B-dependent proliferative advantage and resistance against FAS-induced cell death in B cells 总被引:1,自引:0,他引:1
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Ho L Davis RE Conne B Chappuis R Berczy M Mhawech P Staudt LM Schwaller J 《Blood》2005,105(7):2891-2899
The most frequently recurring translocations in mucosa-associated lymphoid tissue (MALT) B-cell non-Hodgkin lymphoma, t(11;18)(q21;q21) and t(14;18)(q32; q21), lead to formation of an API2-MALT1 fusion or IgH-mediated MALT1 overexpression. Various approaches have implicated these proteins in nuclear factor kappaB (NF-kappa B) signaling, but this has not been shown experimentally in human B cells. Immunohistochemistry showed that MALT1 is predominantly expressed in normal and malignant germinal center B cells, corresponding to the differentiation stage of MALT lymphoma. We expressed MALT1 and apoptosis inhibitor-2 API2/MALT1 in human B-cell lymphoma BJAB cells and found both transgenes in membrane lipid rafts along with endogenous MALT1 and 2 binding partners involved in NF-kappa B signaling, B-cell lymphoma 10 (BCL10) and CARMA1 (caspase recruitment domain [CARD]-containing membrane-associated guanylate kinase [MAGUK] 1). API2-MALT1 and exogenous MALT1 increased constitutive NF-kappa B activity and enhanced I kappa B kinase (IKK) activation induced by CD40 stimulation. Both transgenes protected BJAB cells from FAS (CD95)-induced death, consistent with increases in NF-kappa B cytoprotective target gene expression, and increased their proliferation rate. Expression of a dominant-negative I kappa B alpha mutant showed that these survival and proliferative advantages are dependent on elevated constitutive NF-kappa B activity. Our findings support a model in which NF-kappa B signaling, once activated in a CD40-dependent immune response, is maintained and enhanced through deregulation of MALT1 or formation of an API2-MALT1 fusion. 相似文献
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PURPOSE: This study was performed to compare the clinical performance between the compomer F2000 and amalgam Dispersalloy in Class II restorations in primary molars over a 2-year period. METHODS: Seventy-five amalgam and 75 compomer restorations were placed in 75 children based on a split-mouth design. The restorations were evaluated after 1 week and after 6, 12, 18, and 24 months of oral function. The evaluation consisted of a clinical assessment according to modified Ryge criteria, a radiographic examination using bite-wing radiographs, and an observation of epoxy casts under scanning electron microscopy. RESULTS: The results showed statistically significant differences in the marginal adaptation and anatomic form between amalgam and compomer restorations. A higher number of compomer restorations were rated as Bravo, while a higher number of amalgam restorations were rated as Alpha at 24 months. Significant differences in the failure of the restoration and development of secondary caries were not found between the materials. CONCLUSIONS: The use of compomer F2000 in Class II resorations in primary molars, although it presents a significantly higher number of restorations rated as Bravo regarding the marginal adaptation and anatomic form vs the amalgam, does not increase the risks of developing secondary caries and failure of the restoration over a period of 2 years. 相似文献
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Fatty acid binding proteins (FABPs) are members of a highly conserved family of proteins with the task of protecting a cell's delicate lipid balance. Yet they fail when faced with metabolic or inflammatory stress, turning the cytosol into an inhospitable environment with less than ideal outcomes. This review will focus on how FABPs direct lipid traffic and simultaneously control inflammatory and metabolic pathways under the pressures of the Metabolic Syndrome. 相似文献
58.
Weinberg ML Felicori LF Bello CA Magalhães HP Almeida AP Magalhães A Sanchez EF 《Journal of pharmacological sciences》2004,96(3):333-342
A serine proteinase with kallikrein-like activity (LV-Ka) has been purified to homogeneity from bushmaster snake (Lachesis muta muta) venom. Physicochemical studies indicated that LV-Ka is a single chain glycoprotein with a molecular mass (Mr) of 33 kDa under reducing conditions which was reduced to 28 kDa after treatment with N-Glycosidase F (PNGase F). LV-Ka can be bounded and neutralized by serum alpha2-macroglobulin (alpha2-M), a prevalent mammalian protease inhibitor that is capable of forming a macromolecular complex with LV-Ka (Mr >180 kDa). Cleavage of alpha2-M by the enzyme resulted in the formation of 90-kDa fragments. The proteolytic activity of LV-Ka against dimethylcasein could be inhibited by alpha2-M, and the binding ratio of the inhibitor:enzyme complex was found to be 1:1. The Michaelis constant, Km, and catalytic rate constant, kcat, of LV-Ka on four selective chromogenic substrates were obtained from Lineweaver-Burk plots. LV-Ka exhibits substrate specificities not only for the glandular kallikrein H-D-Val-Leu-Arg-pNA (S-2266) but also for the plasmin substrates S-2251 and Tos-Gly-Pro-Lys-pNA. Bovine kininogen incubated with LV-Ka generated a polypeptide that dose dependently contracted mesenteric arterial rings from spontaneously hypertensive rats (SHR) in a similar way as bradykinin (BK) does. As it happens with BK, LV-Ka generated polypeptide was inhibited by HOE-140, a bradykinin B2-receptor antagonist and by indomethacin, a cyclo-oxygenase inhibitor. These results strongly suggest that the polypeptide generated by LV-Ka by cleavage of bovine kininogen is bradykinin. In addition, our studies may help to understand the mechanism of action involved in hypotension produced by envenomation of bushmaster snake. 相似文献
59.
Effectiveness of smoking cessation self-help materials in a lung cancer screening population 总被引:2,自引:0,他引:2
Clark MM Cox LS Jett JR Patten CA Schroeder DR Nirelli LM Vickers K Hurt RD Swensen SJ 《Lung cancer (Amsterdam, Netherlands)》2004,44(1):13-21
Randomized controlled trials of smoking interventions have not been well-documented for lung cancer screening populations. In this study, we randomly assigned 171 current smokers who were undergoing low-dose fast spiral chest CT (SCTS) for lung cancer screening to receive either standard written self-help materials or a written list of Internet resources for smoking cessation. At the 1-year follow-up, more of the subjects receiving Internet-based resources reported making a stop attempt (68% versus 48%, P=0.011). However, there were no statistically significant differences in 7-day point prevalence quit rates (5% versus 10%) or advancement in motivational readiness to stop smoking (27% versus 30%), respectively, between the groups. Clearly, more investigation is warranted into how to tailor smoking interventions for cancer screening participants. 相似文献
60.