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21.
Stanojević NB Ivanović ZJ Djurovic S Kalimanovska VS Spasić S Ostrić DK Memon L 《International heart journal》2005,46(4):593-600
High plasma HDL-cholesterol (HDL-c) is a well-established protective factor in coronary artery disease (CAD). One of its potential protective mechanisms is the inhibition of the cytokine-induced upregulation of expression of cellular adhesion molecules (CAMs). High sCAM levels were found to be associated with low HDL-c in some studies performed mostly in hyperlipidemic subjects, but this association has not yet been investigated in CAD patients. In addition, conflicting results were obtained from in vitro studies that explored the proposed HDL effect on cytokine-induced CAM expression. The aim of the present case-control study was to investigate whether low HDL-c values are associated with CAM overexpression in normolipidemic CAD patients and healthy individuals, matched according to age and gender. Plasma HDL-c, sICAM-1, sVCAM-1, and sE-selectin were measured in 37 normolipidemic patients with angiographically verified coronary artery disease and in 52 healthy normolipidemic subjects. The sCAM values obtained in the subjects (patients or controls) with low HDL-c levels (< 1.03 mmol/L) were compared with the values in the subjects with high HDL-c (>or= 1.03 mmol/L). No significant difference was found between sICAM-1, sVCAM-1, and E-selectin values obtained in subjects with low and high HDL-c, either among the patients or the healthy controls. In conclusion, low HDL-c levels are not associated with CAM overexpression in normolipidemic CAD patients and healthy subjects. 相似文献
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Tatjana Adzic-Vukicevic Aleksandra Barac Ana Blanka-Protic Marija Laban-Lazovic Bojana Lukovic Vesna Skodric-Trifunovic Salvatore Rubino 《Infection》2018,46(3):357-363
Introduction
Non-tuberculous mycobacteria (NTM) are ubiquitous organisms associated with various infections. The aim of the study was to determine the most relevant clinical characteristics of NTM during the 7-year period.Methodology
A retrospective study of NTM infections was conducted between January 2009 and December 2016. The American Thoracic Society/Infectious Disease Society of America criteria were used to define cases of pulmonary or an extrapulmonary site.Results
A total of 85 patients were included in the study. Pulmonary cases predominated 83/85 (98%), while extrapulmonary NTM were present in 2/95 (2%) patients. Overall, ten different NTM species were isolated. The most common organisms were slow-growing mycobacteria (SGM) presented in 70/85 (82.35%) patients. Isolated SGM strains were Mycobacterium avium complex (MAC) in 25/85 (29.41%) patients, M. xenopi in 20/85 (23.53%) patients, M. kansasii in 15/85 (17.65%) patients and M. peregrinum and M. gordonae in 5/85 (5.88%) patients each. Isolated rapid-growing mycobacteria (RGM) strains were M. abscessus in 8/85 (9.41%) patients, M. fortuitum in 4/85 (4.71%) patients and M. chelonae in 3/85 (3.53%) patients. Almost all patients (98%; 83/85) had comorbidities. Among 75 (88.24%) patients who completed follow-up, 59 (69.41%), 10 (11.76%) and 6 (7%), were cured, experienced relapse and died, respectively.Conclusion
In the present study, pulmonary NTM infections were more frequent compared to extrapulmonary disease forms. SGM were most common isolates with MAC pulmonary disease the most frequently found. Comorbidities have an important role in NTM occurrence. Further investigation should focus on an NTM drug susceptibility testing.24.
Maria Argos Lin Chen Farzana Jasmine Lin Tong Brandon L. Pierce Shantanu Roy Rachelle Paul-Brutus Mary V. Gamble Kristin N. Harper Faruque Parvez Mahfuzar Rahman Muhammad Rakibuz-Zaman Vesna Slavkovich John A. Baron Joseph H. Graziano Muhammad G. Kibriya Habibul Ahsan 《Environmental health perspectives》2015,123(1):64-71
Background: Inorganic arsenic is one of the most common naturally occurring contaminants found in the environment. Arsenic is associated with a number of health outcomes, with epigenetic modification suggested as a potential mechanism of toxicity.Objective: Among a sample of 400 adult participants, we evaluated the association between arsenic exposure, as measured by blood and urinary total arsenic concentrations, and epigenome-wide white blood cell DNA methylation.Methods: We used linear regression models to examine the associations between arsenic exposure and methylation at each CpG site, adjusted for sex, age, and batch. Differentially methylated loci were subsequently examined in relation to corresponding gene expression for functional evidence of gene regulation.Results: In adjusted analyses, we observed four differentially methylated CpG sites with urinary total arsenic concentration and three differentially methylated CpG sites with blood arsenic concentration, based on the Bonferroni-corrected significance threshold of p < 1 × 10–7. Methylation of PLA2G2C (probe cg04605617) was the most significantly associated locus in relation to both urinary (p = 3.40 × 10–11) and blood arsenic concentrations (p = 1.48 × 10–11). Three additional novel methylation loci—SQSTM1 (cg01225779), SLC4A4 (cg06121226), and IGH (cg13651690)—were also significantly associated with arsenic exposure. Further, there was evidence of methylation-related gene regulation based on gene expression for a subset of differentially methylated loci.Conclusions: We observed significant associations between arsenic exposure and gene-specific differential white blood cell DNA methylation, suggesting that epigenetic modifications may be an important pathway underlying arsenic toxicity. The specific differentially methylated loci identified may inform potential pathways for future interventions.Citation: Argos M, Chen L, Jasmine F, Tong L, Pierce BL, Roy S, Paul-Brutus R, Gamble MV, Harper KN, Parvez F, Rahman M, Rakibuz-Zaman M, Slavkovich V, Baron JA, Graziano JH, Kibriya MG, Ahsan H. 2015. Gene-specific differential DNA methylation and chronic arsenic exposure in an epigenome-wide association study of adults in Bangladesh. Environ Health Perspect 123:64–71; http://dx.doi.org/10.1289/ehp.1307884 相似文献
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Estelle Glais Vesna orevi Jelena Papan Bruno Viana Miroslav D. Dramianin 《RSC advances》2018,8(33):18341
MgTiO3 nanoparticles doped with Mn4+, with homogeneous size ranging about 63.1 ± 9.8 nm, were synthesized by a molten salt assisted sol gel method. These nanoparticles have been investigated as optical thermal sensors. The luminescence of tetravalent manganese ion in octahedral environment within the perovskite host presents drastic variations with temperature. Three different thermometry approaches have been proposed and characterized. Two luminescence intensity ratios are studied. Firstly between the two R-lines of Mn4+ emission at low temperature (−250 °C and −90 °C) with a maximal sensitivity of 0.9% °C−1, but also secondly between 2E → 4A2 (R-line) and the 4T2 → 4A2 transitions. This allows studying the temperature variation within a larger temperature range (−200 °C to 50 °C) with a sensitivity between 0.6% °C−1 and 1.2% °C−1 over this range. The last proposed method is the study of the lifetime variation versus temperature. The effective lifetime value corresponds to a combination of transitions from two excited energy levels of the tetravalent manganese (2E and 4T2) in thermal equilibrium toward the fundamental 4A2 state. Since the more energetic transition (4T2 → 4A2) is spin-allowed, contrary to the 2E → 4A2 one, the lifetime drastically decreases with the increase in temperature leading to an impressive high sensitivity value of 4.1% °C−1 at 4 °C and an exceptional temperature resolution of 0.025 °C. According to their optical features, MgTiO3:Mn4+ nanoparticles are indeed suitable candidates for the luminescence temperature probes at the nanoscale over several temperature ranges.Luminescence properties of MgTiO3 nanoparticles doped with Mn4+ ions are investigated for precise temperature determination. 相似文献
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Influence of various proton pump inhibitors on intestinal metaplasia in noneradicated Helicobacter pylori patients 总被引:1,自引:0,他引:1
Marusic M Babic Z Nesanovic M Lucijanic-Mlinac M Stajcar V 《World journal of gastroenterology : WJG》2005,11(15):2334-2336
AM: Intestinal metaplasia (IM) is more often found in patients with Helicobacterpylori(Hpylori) infection, while eradication of H pylori results in significant reduction in the severity and activity of chronic gastritis. We aimed to determine in patients with unsuccessful eradication of Hpylori the role of various proton pump inhibitors (PPIs) having different mechanisms in the resolution of IM. METHODS: We confirmed endoscopically and pathohistologically (Sydney classification) the IM in 335 patients with gastritis before and after medication for eradication of H pylori (Maastricht Protocol 2002). H pylori infection was determined by using histology, urease test and culture. Control endoscopy and histology were done after 30 d and thereafter (within 1 year). Unsuccessful eradication was considered if only one of the three tests (histology, urease and culture) was negative after therapy protocol. We used omeprazole, pantoprazole, lansoprazole in therapy protocols (in combination with two antibiotics). RESULTS: We found no significant difference in resolution of IM by using different PPI between the groups of eradicated and noneradicated patients (P<0.4821 and P<0.4388, respectively). CONCLUSION: There is no significant difference in resolution of intestinal metaplasia by different proton pump inhibitors. 相似文献
29.
Dragan Deli Mira Goti Vladimir Otri Vesna Fridman Predrag Nikoli Ljiljana Jemuovi Vladimir Nikolov Sonja
erjav andor Groza 《Liver international》1993,13(6):302-304
ABSTRACT— In 614 HBsAg-positive Yugoslavian patients, radioimmunoassay testing for anti-delta showed the presence of this antibody in serum in 11.2%. Of the patients, 213 belonged to a risk group (i.v. drug users, hemophiliacs, hemodialysed patients and patients with posttransfusion hepatitis); a significant number of these patients (63; 29.6%) were found to have anti-delta. A second group was composed of 401 HBsAg-positive patients from the general population (patients with acute hepatitis B, with fulminant hepatitis B and patients with chronic HBV infection); delta infection was found only in six (1.5%). Immunohistochemical methods failed to demonstrate the delta antigen in the livers of 73 patients with chronic HBV infection. Testing the liver of 36 patients with fulminant hepatitis B for delta antigen demonstrated this reactivity in only one (2.8%) liver sample. Delta antigen was also found in the liver of a female patient who underwent biopsy in 1972. The results of this study suggest the HDV is not endemic in Yugoslavia; however, it is frequently found in patients at risk of blood exposure, primarily i.v. drug users. 相似文献
30.
Connor WJ Bevington Ju-Chieh Cheng Ivan S Klyuzhin Mariya V Cherkasova Catharine A Winstanley Vesna Sossi 《Journal of cerebral blood flow and metabolism》2021,41(1):116
Current methods using a single PET scan to detect voxel-level transient dopamine release—using F-test (significance) and cluster size thresholding—have limited detection sensitivity for clusters of release small in size and/or having low release levels. Specifically, simulations show that voxels with release near the peripheries of such clusters are often rejected—becoming false negatives and ultimately distorting the F-distribution of rejected voxels. We suggest a Monte Carlo method that incorporates these two observations into a cost function, allowing erroneously rejected voxels to be accepted under specified criteria. In simulations, the proposed method improves detection sensitivity by up to 50% while preserving the cluster size threshold, or up to 180% when optimizing for sensitivity. A further parametric-based voxelwise thresholding is then suggested to better estimate the release dynamics in detected clusters. We apply the Monte Carlo method to a pilot scan from a human gambling study, where additional parametrically unique clusters are detected as compared to the current best methods—results consistent with our simulations. 相似文献