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81.

Objective

Apoptosis plays an important role in the regulation of gastric epithelial cell number and gastrointestinal disorders induced by Helicobacter pylori (Hp). Heat shock proteins (HSPs) are involved in cell integrity, cell growth and in gastric mucosa colonized by Hp. COX-2 was implicated in Hp-induced carcinogenesis but the effects of this germ and CagA cytotoxin on HSP70, COX-2, Bax and Bcl-2 in gastric cancer epithelial cells have been little studied.

Material and methods

We determined the expression for HSP70, Bax and Bcl-2 in human gastric epithelial MKN7 cells incubated with live strain Hp (cagA?+?vacA+) with or without co-incubation with exogenous CagA and NS-398, the selective COX-2 inhibitor. After 3–48?h of incubation, the expression of HSP70, COX-2, Bax and Bcl-2 mRNA and proteins were determined by RT-PCR and immunoprecipitation.

Results

Hp inhibited expression for HSP70 and this was significantly potentiated by exogenous CagA. Co-incubation of epithelial cells with Hp, without or with CagA increased Bax expression and simultaneously decreased expression for Bcl-2. The increase in COX-2 mRNA and Bax expression were significantly inhibited by NS-398. We conclude that Hp promotes apoptosis in adenocarcinoma gastric epithelial cells in vitro and this is associated with activation of COX-2 and inhibition of HSP70.  相似文献   
82.

Background

Several in vivo and in vitro studies have shown that metal-rich particles may enhance allergic responses to house dust mites and induce an increased release of allergy-related cytokines.

Objectives

The main goal of this analysis is to define the possible association of intrauterine exposure to lead and mercury with the occurrence of skin sensitization to common aeroallergens in early childhood.

Material and methods

The present study refers to a sample of 224 women in the second trimester of pregnancy recruited from Krakow inner city area who had full term pregnancies and whose children underwent skin prick testing (SPT) at the age of 5. Lead and mercury levels were assessed in cord blood and retested in children at age of 5 years. Aeroallergen concentrations in house dust were measured at the age of 3 years. The main health outcome (atopic status) was defined as the positive SPT to at least one common aeroallergen (Der f1, Der p1, Can f1 and Fel d1) at the age of 5 years. In the statistical analysis of the association between atopic status of children and exposure to metals, the study considered a set of covariates such as maternal characteristics (age, education, atopy), child’s gender, number of older siblings, prenatal (measured via cord blood cotinine) and postnatal environmental tobacco smoke together with exposure to polycyclic aromatic hydrocarbons (PAH) as measured by PAH-DNA adducts.

Results and conclusion

In the binary regression analysis, which controlled for the confounders, the risk ratio (RR) estimate for atopic sensitization was significantly associated with the lead exposure (RR=2.25, 95%CI: 1.21−4.19). In conclusion, the data suggest that even very low-level of prenatal lead exposure may be implicated in enhancing sensitization to common aeroallergens in early childhood.  相似文献   
83.
84.
The currently recommended method of venous thromboembolism (VTE) treatment is the application of vitamin K antagonists (VKA) in most patients, and low-molecular-weight heparins (LMWH) in selected groups. The VKA dose adjustment is difficult which might well render the treatment ineffective. The study aimed to compare LMWH with VKA in treating VTE in terms of efficacy and safety. A systematic review of literature and the meta-analysis of the treatment results were performed. The main differences between LMWH and VKA in terms of their respective effectiveness in treating VTE consist in appreciably more advantageous effects of LMWH in preventing deep venous thrombosis (DVT). The key difference in terms of respective safety is the greater effectiveness of LMWH inpreventing minor bleedings. The advantage of LMWH in cancer patients consists predominantly in a significantly better protection against DVT episodes, whereas the advantage of LMWH in non-cancer patients is mainly owed to better protection against minor bleedings. In none of the analysed outcomes of VTE treatment, the application of VKA proved to hold any advantage over LMWH. Although, arguably, there might well be sufficient medical grounds to propose more widespread use of LMWH, it still remains a debatable issue whether the currently used therapeutic standard should also be modified accordingly. Apart from the actual findings of the present meta-analysis, pertinent economic considerations must also be addressed.  相似文献   
85.
The importance of allogeneic hematopoietic stem cell transplantation (allo‐HSCT) for survival outcomes in patients with acute myeloid leukemia (AML) currently remains unclear. The study aimed to compare measures of clinical treatment for patients with AML in CR1 (the first complete remission) with or without being subjected to allo‐HSCT. These consisted of leukemia‐free survival (LFS), overall survival (OS), cumulative incidence of relapse (CIR), and non‐relapse mortality disease (NRM). Subjects were 622 patients, median age of 44, forming part of the prospective, randomized, and multicenter clinical Polish Adult Leukemia Group trials during 1999–2008. The Mantel–Byar approach was used to assess allo‐HSCT on survival endpoints, accounting for a changing transplant status. Undergoing allo‐HSCT significantly improved the LFS and OS for the entire group of patients with AML in CR1, along with the DAC induction subgroup and for the group with unfavorable cytogenetics aged 41–60. The CIR demonstrated that allo‐HSCT reduced the risk of relapse for patients with AML in CR1 and those with an unfavorable cytogenetic risk. In addition, the NRM analysis showed that allo‐HSCT significantly reduced the risk of death unrelated to relapse for the entire group of AML patients in CR1 and aged 41–60. The allo‐HSCT treatment particularly benefitted survival for the AML in CR1 group having an unfavorable cytogenetic prognosis. Am. J. Hematol. 90:904–909, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
86.
The inhibitory effect of duodenal acidification and intraduodenal fat infusion on pentagastrin-stimulated gastric secretion in normal subjects and in patients with duodenal ulcer was studied. Intraduodenal infusion of acid resulted in inhibition of HCl secretion found to be significant only in ulcer patients. Pepsin output, although lower during the first 15 minutes of duodenal acidification, later increased. Intraduodenal infusion of olive oil resulted in significant inhibition of HCl and pepsin output in both groups of patients, which was maximal 45–60 minutes after the beginning of fat infusion. Gastric secretion was more readily inhibited in ulcer patients than in normal subjects; this difference was particularly evident in inhibition of pepsin secretion. In addition, decrease in concentration of HCl and pepsin was observed to be significant only in ulcer patients. Mechanisms by which duodenal acidification and fat inhibit gastric secretion are discussed. The results obtained suggest that secretin, which is probably responsible for inhibition after duodenal acidification, is not the inhibitor during inhibition by fat. The ulcer patients were found to have unimpaired mechanisms of inhibition by acid and fat.  相似文献   
87.
Models that account for sex-specific behavior and population dynamics are becoming more common in the stock assessment of sexually dimorphic fishes. However, such models can be data intensive and require some knowledge or assumptions about the sex ratio of fishery landings. A recent stock assessment review of Summer Flounder Paralichthys dentatus identified the need to account for sex-specific fishing mortality in the assessment model; however, no data on the sex composition of the catch were available. Fishery-independent, sex-specific information for this species is collected annually by the National Marine Fisheries Service's Northeast Fisheries Science Center during their bottom trawl survey. Sex at age from the survey could be applied to the fishery landings if the probability of landing a given sex at a given age is equivalent for fish collected by the survey and those in the landings. To generate the first regionally comprehensive database on the sex ratio of Summer Flounder landings and to determine the efficacy of using survey sex-at-age keys to estimate the sex of landed fish, we recorded the sex composition of the commercial and recreational catches of Summer Flounder (n = 31,912) in 2010 and 2011. When (1) trawl survey length data were left-truncated to simulate the minimum retention sizes in the fisheries and (2) age–length keys generated from fishery-dependent data were applied to length frequency distributions from the survey to simulate the growth rates of landed fish, the sex-at-age pattern in the survey-derived data closely resembled the patterns in the catch. However, statistically significant differences in sex at age remained between the catch and the survey-derived data. We hypothesize that these differences are attributable to differences in the spatiotemporal distributions of the sexes and of the survey and fishing effort.

Received March 9, 2015; accepted June 23, 2015  相似文献   

88.
Poloxalene, a hydrophobic surfactant, is known to prevent hypercholesterolemia in animals fed a high-fat, high-cholesterol diet. It has not been demonstrated, however, whether this agent is of benefit when hypercholesterolemia is induced in animals by means other than the feeding of a high-fat diet. In this study, hypercholesterolemia was produced in rabbits by feeding a low-fat, cholesterol-free diet with dietary protein supplied by casein for a period of 8 weeks. Controls were given this diet without poloxalene and experimentals were given the diet with poloxalene. Total serum cholesterol levels increased in both groups, but the rise was greater for the control group. Lipoprotein analysis performed at the conclusion of the study showed significantly greater low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol levels in the control group as compared to the experimental group. Total protein and apolipoprotein B (apo B) were also greater in control LDL. It was concluded that poloxalene favorably affects this model of hypercholesterolemia as total serum cholesterol, LDL cholesterol, and LDL apo B were all less and the HDL cholesterol to LDL cholesterol ratio was higher in surfactant-treated rabbits.  相似文献   
89.
Tissue harmonic imaging of thyroid nodules: initial experience.   总被引:1,自引:0,他引:1  
OBJECTIVE: To determine the impact of tissue harmonic imaging on visualization of the thyroid and gray scale contrast between thyroid nodules and adjacent thyroid parenchyma. METHODS: A prospective study was performed on 144 patients (148 lesions) undergoing sonographically guided fine-needle biopsy. The fundamental frequency and tissue harmonic images were obtained on a scanner with a wideband 7.5-MHz linear probe. One hundred forty-two benign nodules, 2 papillary carcinomas, 1 anaplastic carcinoma, and 1 metastatic lesion were found. In 1 case a suggestion of a follicular carcinoma was raised, and in 1 case no diagnostic material was obtained. The gray scale intensity of the lesions and adjacent thyroid tissue was measured with graphics software, and the gray scale contrast between lesions and adjacent thyroid tissue was calculated. Additionally, the overall conspicuity and border definition were evaluated by 2 independent observers. RESULTS: Tissue harmonic imaging improved the gray scale contrast between thyroid nodules and adjacent thyroid parenchyma in 116 lesions (78.4%). The overall conspicuity and border definition were improved or equal in the harmonic mode for most lesions. CONCLUSIONS: The tissue harmonic imaging technique used as an adjunct to conventional thyroid sonography may improve lesion detectability and characterization.  相似文献   
90.

Background

The randomized EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial reported a similar rate of the 3-year composite primary endpoint of death, myocardial infarction (MI), or stroke in patients with left main coronary artery disease (LMCAD) and site-assessed low or intermediate SYNTAX scores treated with percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). Whether these results are consistent in high-risk patients with diabetes, who have fared relatively better with CABG in most prior trials, is unknown.

Objectives

In this pre-specified subgroup analysis from the EXCEL trial, the authors sought to examine the effect of diabetes in patients with LMCAD treated with PCI versus CABG.

Methods

Patients (N = 1,905) with LMCAD and site-assessed low or intermediate CAD complexity (SYNTAX scores ≤32) were randomized 1:1 to PCI with everolimus-eluting stents versus CABG, stratified by the presence of diabetes. The primary endpoint was the rate of a composite of all-cause death, stroke, or MI at 3 years. Outcomes were examined in patients with (n = 554) and without (n = 1,350) diabetes.

Results

The 3-year composite primary endpoint was significantly higher in diabetic compared with nondiabetic patients (20.0% vs. 12.9%; p < 0.001). The rate of the 3-year primary endpoint was similar after treatment with PCI and CABG in diabetic patients (20.7% vs. 19.3%, respectively; hazard ratio: 1.03; 95% confidence interval: 0.71 to 1.50; p = 0.87) and nondiabetic patients (12.9% vs. 12.9%, respectively; hazard ratio: 0.98; 95% confidence interval: 0.73 to 1.32; p = 0.89). All-cause death at 3 years occurred in 13.6% of PCI and 9.0% of CABG patients (p = 0.046), although no significant interaction was present between diabetes status and treatment for all-cause death (p = 0.22) or other endpoints, including the 3-year primary endpoint (p = 0.82) or the major secondary endpoints of death, MI, or stroke at 30 days (p = 0.61) or death, MI, stroke, or ischemia-driven revascularization at 3 years (p = 0.65).

Conclusions

In the EXCEL trial, the relative 30-day and 3-year outcomes of PCI with everolimus-eluting stents versus CABG were consistent in diabetic and nondiabetic patients with LMCAD and site-assessed low or intermediate SYNTAX scores.(Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization [EXCEL]; NCT01205776)  相似文献   
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