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81.
82.
Epigenetic therapy is emerging as a potential therapy for solid tumors. To investigate its mechanism of action, we performed integrative expression and methylation analysis of 63 cancer cell lines (breast, colorectal, and ovarian) after treatment with the DNA methyltransferase inhibitor 5-azacitidine (AZA). Gene Set Enrichment Analysis demonstrated significant enrichment for immunomodulatory pathways in all three cancers (14.4-31.3%) including interferon signaling, antigen processing and presentation, and cytokines/chemokines. Strong upregulation of cancer testis antigens was also observed. An AZA IMmune gene set (AIMs) derived from the union of these immunomodulatory pathway genes classified primary tumors from all three types into “high” and “low” AIM gene expression subsets in tumor expression data from both TCGA and GEO. Samples from selected patient biopsies showed upregulation of AIM genes after treatment with epigenetic therapy. These results point to a broad immune stimulatory role for DNA demethylating drugs in multiple cancers.  相似文献   
83.
Seven new compounds, O-trans-cinnamoylglutinol (1), 22β-hydroxy-12-oleanen-3-one (2), 15α,16α-epoxy-12-oleanen-3-one (3), 29-hydroxy-12-oleanene-3,22-dione (4), 22β,29-dihyroxy-12-oleanen-3-one (5), 2,3-(methylenedioxy)-4-methoxy-5-methylphenol (8), and 2,3,6-trimethoxy-5-methylphenol (9), as well as two first isolated from natural sources, 25-cycloartene-3,24-dione (6) and 24ξ-hydroxy-25-cycloarten-3-one (7), were characterized from Derris laxiflora. The structures of these compounds were determined by analysis of their spectroscopic data.  相似文献   
84.
Significant advances in the postnatal management of patients with congenital diaphragmatic hernia (CDH) have resulted in a remarkable improvement in survival rates over the past two decades. The success of current postnatal management of CDH patients has rendered fetal intervention to be limited to the most severe cases, and the role for prenatal treatment of CDH patients remains unclear. The adoption of lung-preserving strategies including high-frequency oscillatory ventilation (HFOV) and extracorporeal membrane oxygenation (ECMO) have improved CDH outcomes especially in those patients with significant ventilatory or circulatory compromise. Survival rates of up to 90% are being reported in some high-volume centers. However, the increased survival in CDH patients has been accompanied by an increase in neurological, nutritional and musculoskeletal morbidity among the long-term survivors. This has resulted in the need to provide resources for the long-term follow-up and support of this patient population. In this article, the postnatal management strategies and primary and secondary outcomes of high-volume international pediatric surgical centers will be reviewed. Finally, the role of a multidisciplinary management team for the follow-up of long-term CDH survivors will be discussed.  相似文献   
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86.
Some evidence suggests that smoking, a family history of hematopoietic cancer, and use of hair dyes are associated with t(14;18)-defined subsets of non-Hodgkin's lymphoma (NHL) in men. To further evaluate these associations and to expand them to women, the authors determined t(14;18)(q32;q21) status by fluorescence in situ hybridization in 172 of 175 tumor blocks from a population-based case-control study conducted in Nebraska during 1983-1986. Exposures in 65 t(14;18)-positive cases and 107 t(14;18)-negative cases were compared with those among 1,432 controls. Odds ratios and 95% confidence intervals were calculated using polytomous logistic regression. Among men, smoking was not associated with risk of t(14;18)-positive or -negative NHL. Among women who had ever smoked cigarettes, there was an association with risk of t(14;18)-negative NHL (odds ratio (OR) = 1.9, 95% confidence interval (CI): 1.1, 3.3) but not t(14;18)-positive NHL (p-difference = 0.01). The risks for t(14;18)-negative NHL among women increased with longer duration (>30 years: OR = 2.1, 95% CI: 1.1, 4.1) and early initiation (age 相似文献   
87.
IntroductionThe Bombay phenotype is a rare blood group determined by the absence of H antigens. Bombay individuals produce anti-H, a clinically significant antibody that react against all ABO blood group. Anti-H can mask underlying alloantibody during antibody investigation, a challenge in current transfusion practice. The aim of this article is to explore saliva inhibition, a novel method to detect underlying alloantibody in Bombay individuals.Case PresentationThe case is a 93-year-old female transfused with pre-donated autologous blood for a surgery. We determined anti-H subclass and thermal amplitude, secretor status, and optimal ratio of saliva and Bombay plasma. Plasma samples containing anti-H were spiked with anti-Fy(a) to determine the effectiveness of saliva inhibition in uncovering underlying alloantibodies.ResultsAnti-H was confirmed to be predominately IgM with broad thermal amplitude. Tube immediate spin (IS) showed stronger anti-H reactivity compared to column agglutination technology (CAT). Spiked anti-Fy(a) was successfully detected using saliva inhibition method.ConclusionTube IS appears more sensitive to anti-H. Saliva inhibition appears to be a promising method to detect underlying alloantibody in the plasma of Bombay phenotype individuals.  相似文献   
88.
We consider the situation of estimating the marginal survival distribution from censored data subject to dependent censoring using auxiliary variables. We had previously developed a nonparametric multiple imputation approach. The method used two working proportional hazards (PH) models, one for the event times and the other for the censoring times, to define a nearest neighbor imputing risk set. This risk set was then used to impute failure times for censored observations. Here, we adapt the method to the situation where the event and censoring times follow accelerated failure time models and propose to use the Buckley–James estimator as the two working models. Besides studying the performances of the proposed method, we also compare the proposed method with two popular methods for handling dependent censoring through the use of auxiliary variables, inverse probability of censoring weighted and parametric multiple imputation methods, to shed light on the use of them. In a simulation study with time‐independent auxiliary variables, we show that all approaches can reduce bias due to dependent censoring. The proposed method is robust to misspecification of either one of the two working models and their link function. This indicates that a working proportional hazards model is preferred because it is more cumbersome to fit an accelerated failure time model. In contrast, the inverse probability of censoring weighted method is not robust to misspecification of the link function of the censoring time model. The parametric imputation methods rely on the specification of the event time model. The approaches are applied to a prostate cancer dataset. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
89.
Background: Nutrition and inflammation have been implicated in predicting mortality in patients on peritoneal dialysis (PD). Serum albumin and globulin can be regarded for the nutritional and inflammatory status. However, there is lack of data to evaluate the synergistic effect of albumin and globulin on mortality prediction. Methods: In 554 patients initiating PD from January 2001 to July 2016, we divided them into four groups by the combination of two categories of low vs. high albumin and low vs. high globulin. The median values for albumin and globulin were chosen to classify them into low or high groups. Their associations with all-cause and cardiovascular (CV) mortality were examined in Cox regression models adjusted for confounding clinical and laboratory data. Results: Patients, 52.91 ± 15.2 years old and 47.8% men, had a median (interquartile range) value of 3.3 (2.9–3.8) g/dL for albumin and 2.8 (2.5–3.2) g/dL for globulin, respectively. Patients with low albumin and high globulin had the highest all-cause mortality and CV mortality, with adjusted hazard ratios of 3.87 (95% CI 1.83–8.20, p < 0.001) and 5.65 (95% CI 2.23–14.34, p < 0.001), respectively, compared with those with a high albumin and low globulin having the lowest mortality rate. Sensitivity analyses further confirmed this relationship. Conclusions: A patient profile of either low albumin or high globulin is linked to a higher risk for mortality, particularly for a profile of both low albumin and high globulin compared with one without either of them. Further studies are needed to explore the mechanisms underlying this phenomenon and how to improve clinical outcomes in those high-risk patients.  相似文献   
90.
The effects of atriopeptin II on calcium fluxes in rabbit aorta   总被引:3,自引:0,他引:3  
Effects of atriopeptin II (AP II) at 10(-7) M on the 45Ca flux and contractile responses to vasoconstrictors including norepinephrine (NE), angiotensin II (angio II) and high K were studied in isolated rabbit aortic strips. Augmentation of 45Ca efflux from aorta in normal physiological saline (PSS) due to NE and angio II each at 3 X 10(-7) M was greatly inhibited by AP II, suggesting that stimulated increase in cytosolic Ca2+ was suppressed. In contrast, the 45Ca efflux responses to KCl (20 and 40 mM) were not affected by AP II. Furthermore, the marked inhibition of contractile responses to NE (-58%) and angio II (-57%) by AP II was accompanied by significant decreases in 45Ca influx, whereas AP II exhibited only a modest inhibition on KCl (40 mM)-induced contraction (-28%) without affecting the accompanying increase in 45Ca influx. The 45Ca efflux from aortae in Ca2+-free PSS due to NE was markedly diminished by AP II, suggesting impairment of intracellular Ca2+ release. With tissues in either a basal or post-stimulation state (tissue Ca2+ previously increased with KCl stimulation), AP II did not stimulate 45Ca efflux in Ca2+-free PSS, suggesting its lack of effect on Ca extrusion. It is concluded that AP II is preferentially antagonistic against vascular responses to NE and angio II vs. high K and that inhibition of Ca entry and release forms the primary basis of its potent vasorelaxant action against vasoconstrictors.  相似文献   
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