508 research outputs found
Molecular basis for solvent dependent morphologies observed on electrosprayed surfaces
We study the causes of the observed tunable hydrophobicity of poly(styrene-co-perfluoroalkyl ethylacrylate) electrosprayed in THF, DMF, and THFâ:âDMF (1â:â1) solvents. Under the assumption that equilibrium morphologies in the solvent significantly affect the patterns observed on electrosprayed surfaces, we use atomistic and coarse-grained simulations supported by dynamic light scattering (DLS) experiments to focus on the parameters that affect the resulting morphology of superhydrophobic electrosprayed beads. The differing equilibrium chain size distributions in these solvents examined by DLS are corroborated by chain dimensions obtained via molecular dynamics simulations. Mesoscopic morphologies monitored by dissipative particle dynamics simulations explain experimental observations; in particular, the preference of the polymer for THF over DMF in the binary mixture rationalizes the dual scale roughness driven by stable microphase separation. Drying phenomena that affect resultant dual-scale roughness are described in three stages, each interpreted by concentration dependent diffusion and surface mass transfer coefficients of the solvents. Irrespective of the presence of polar groups in the structure, a conflict between the lower-boiling point solvent adhering to the polymer and the less volatile solvent abundant in the bulk leads to perfectly hydrophobic surfaces
Etiopathogenesis of Sheehanâs Syndrome: Roles of Coagulation Factors and TNF-Alpha
Sheehanâs Syndrome (SS) is defined as pituitary hormone deficiency due to ischemic infarction of the pituitary gland as a result of massive postpartum uterine hemorrhage. Herein, we aimed to investigate the roles of Factor II (G20210A), Factor V (G1691A), MTHFR (C677T and A1298C), PAI-1 4G/5G, and TNF-α (-308ââG>A) gene polymorphisms in the etiopathogenesis of SS. Venous blood samples were obtained from 53 cases with SS and 43 healthy women. Standard methods were used to extract the genomic DNAs. Factor II (G20210A), Factor V (G1691A), and MTHFR (C677T and A1298C) polymorphisms were identified by real-time PCR. PAI-1 4G/5G and TNF-α (-308ââG>A) gene polymorphisms were detected with polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods. According to statistical analysis, none of the polymorphisms were found to be significantly higher in the SS group compared to the control group. Hence, we suggest that genetic factors other than Factor II, Factor V, MTHFR, PAI-1, and TNF-α gene polymorphisms should be researched in the etiopathogenesis of SS
PrzepĆyw w gaĆÄzi przedniej zstÄpujÄ cej lewej tÄtnicy wieĆcowej u pacjentĂłw z marskoĆciÄ wÄ troby
Introduction. Although cardiac function appears normal in patients with cirrhosis at rest, cardiac function deteriorates in these patients under stress conditions. Decreased cardiac function against stress may be due to coronary microvascular dysfunction in these patients. In this study, we aimed to evaluate coronary microvascular dysfunction in patients with cirrhosis by measuring coronary flow reserve (CFR) by transthoracic echocardiography.
Materials and methods. Thirty-eight patients with cirrhosis and 32 healthy subjects (as control group) were examined. In addition to standard two-dimesional (2D) and Doppler echocardiography, coronary flow velocity was measured by pulsed-wave Doppler from the middle to the distal part of the left anterior descending artery at the beginning and after dipyridamole infusion in the hyperemic state. CFR was measured as the ratio of hyperemic peak diastolic flow rate to basal peak diastolic flow rate.
Results. CFR was significantly lower in the cirrhosis group than in the control group (2.01 ± 0.31 and 2.84 ± 0.62; p < 0.0001). Increasing age, increasing myocardial mass, high aspartate aminotransferase and alanine aminotransferase, low hemoglobin, high C-reactive protein, decreased cholesterol and platelet levels were found to be associated with the reduction in CFR. Among all these factors only, the hemoglobin level and age were independent determinants of impaired CFR.
Conclusions. Impaired CFR in patients with cirrhosis promotes coronary microvascular dysfunction. The coronary microvascular dysfunction can potentially contribute to the development of cirrhotic cardiomyopathy.WstÄp. ChociaĆŒ czynnoĆÄ serca u pacjentĂłw z marskoĆciÄ
wÄ
troby oceniana w spoczynku wydaje siÄ prawidĆowa, to w warunkach wysiĆku fizycznego lub obciÄ
ĆŒenia farmakologicznego ulega ona pogorszeniu. Zaburzenie czynnoĆci serca podczas obciÄ
ĆŒenia moĆŒe byÄ spowodowane dysfunkcjÄ
mikrokrÄ
ĆŒenia wieĆcowego u tych chorych. Celem badania byĆa ocena dysfunkcji mikrokrÄ
ĆŒenia wieĆcowego u pacjentĂłw z marskoĆciÄ
wÄ
troby przez pomiar rezerwy przepĆywu wieĆcowego (CRF) za pomocÄ
echokardiografii przezklatkowej.
MateriaĆ i metody. Do badania wĆÄ
czono 38 chorych z marskoĆciÄ
wÄ
troby i 32 osoby zdrowe (grupa kontrolna). OprĂłcz standardowej echokardiografii dwuwymiarowej (2D) i echokardiografii doplerowskiej prÄdkoĆÄ przepĆywu wieĆcowego w odcinkach Ćrodkowym i dystalnym gaĆÄzi przedniej lewej tÄtnicy zstÄpujÄ
cej zmierzono za pomocÄ
badania dopplerowskiego metodÄ
fali pulsacyjnej bezpoĆrednio przed wlewem dipirydamolu i po nim. RezerwÄ przepĆywu wieĆcowego mierzono jako stosunek maksymalnego przepĆywu rozkurczowego w obciÄ
ĆŒeniu do maksymalnego przepĆywu rozkurczowego w spoczynku.
Wyniki. Rezerwa przepĆywu wieĆcowego byĆa istotnie niĆŒsza w grupie z marskoĆciÄ
wÄ
troby niĆŒ w grupie kontrolnej (2,01 ± 0,31 i 2,84 ± 0,62; p < 0,0001). Stwierdzono, ĆŒe ze zmniejszeniem CFR wiÄ
zaĆy siÄ: wiek, zwiÄkszenie masy miÄĆnia sercowego, wysoka aktywnoĆÄ aminotransferaz asparaginianowej i alaninowej, niskie stÄĆŒenie hemoglobiny, wysokie stÄĆŒenie biaĆka C-reaktywnego, obniĆŒone stÄĆŒenie cholesterolu i zmniejszona liczba pĆytek krwi. Jednak tylko stÄĆŒenie hemoglobiny i wiek byĆy niezaleĆŒnymi determinantami zmniejszonej CFR.
Wnioski. Zmniejszenie CFR u chorych z marskoĆciÄ
wÄ
troby sprzyja dysfunkcji mikrokrÄ
ĆŒenia wieĆcowego, ktĂłra moĆŒe prowadziÄ do rozwoju kardiomiopatii wÄ
trobowej (marskiej)
Prevalence of Helicobacter pylori in symptomatic patients and detection of clarithromycin resistance using melting curve analysis
AbstractBackground:Clarithromycin is often a component of combination therapies for Helicobacter pylori eradication; however, increases in resistance rates have decreased the success of the treatment.Objective:This study was designed to determine the prevalence of H pylori infection in symptomatic patients and to detect clarithromycin resistance rates using melting curve analysis.Methods:Patients scheduled for upper endoscopy at the Endoscopy Unit of the Department of Gastroenterology, Duzce University, Medical Faculty Hospital, Konuralp/Duzce, Turkey, were assessed for enrollment in the study. Two pairs of gastric biopsy specimens (antrum and corpus) were obtained from each study patient. Histopathologic examination, rapid urease test, culture, and polymerase chain reaction (PCR) of the specimens were used to identify H pylori infection. Clarithromycin resistance was detected using melting curve analysis.Results:Seventy-five patients (41 women, 34 men; mean [SD]age, 42.6 [14.5] years [range, 17â70 years]) were included in the study. Using histopathology and rapid urease test, H pylori was detected in 40 (53.3%) of the 75 specimens. H pylori was detected using PCR in 40 (53.3%) specimens and by culture in 10 (13.3%) specimens. The specificity and sensitivity of PCR and culture were interpreted by comparing them with the results of histopathologic examination and urease tests. The specificity and sensitivity of PCR were 68.6% and 72.5%, respectively, and the specificity and sensitivity of culture were 97.1% and 22.5%, respectively. Of the 40 isolates, 21 (52.5%) were susceptible to clarithromycin, 12 (30.0%) were resistant, and a mixed susceptibility pattern was detected in 7 (17.5%) specimens. H pylori isolates from 19 (79.2%) of the 24 patients who had formerly used clarithromycin showed clarithromycin resistance.Conclusions:The prevalence of H pylori infection was 53.3% for the symptomatic patients in this study, and 47.5% of the isolates showed clarithromycin resistance using melting curve analysis. The PCR-based system used in this study was accurate for the detection of H pylori infection as well as clarithromycin susceptibility testing directly in biopsy specimens
Transdisciplinary diagnostic framework for biodiversity decision-making assessment. D1.7
This deliverable describes the process of developing a transdisciplinary diagnostic framework for biodiversity decision-making carried out in Work Package 1 (WP1) of the EU funded research project PLANET4B. The aim of the process was to help researchers and practitioners in our project become more conscious of the theoretical approaches and languages that may condition the interventions we study and the policy and additional recommendations that we make to societal actors. The starting proposition for this work was that we as PLANET4B partners come from a wide range of different disciplines and practices. Therefore, we needed a shared learning process of our different theoretical and practical lenses and languages. This is necessary to increase our potential as a project to design for transformational change in Work Packages to follow. We report on our testing of Meadowsâ (1999) leverage points framework (LPF) as a potential shared conceptual language for transformational change across the places, actors and theories that situate both placebased and sectoral case studies in the project. We report on the opportunities and limitations of the LPF in connecting to (i) theories of change used by research partners in their cases, as well as (ii) bridging conceptually to other âintegrating analytical approachesâ where PLANET4B has partner expertise; namely âintersectionality analysisâ, âdiscourse analysisâ and âreflexivity-contextualisation of interventionsâ. The report recognises that these integrating approaches are but a subset of possible systems analysis tools in transformative change research. The process of understanding and applying Meadowsâ (1999) leverage points framework achieved some shared language and understanding across research disciplines. It helped us to compare assumptions about transformative change across our different case studies. As such, we think we achieved the âprocess objectiveâ of this initial stage of PLANET4B of using a common framework to diagnose our case studies. However, case studies and experts on other integrating analytical approaches identified several limitations of the LPF. Limitations include the LPF itself being a particular theoretical systems analysis lens which in some cases could exclude practitioners through its unfamiliar concepts. Furthermore, the LPF was identified as being âstructuralistâ or âmechanisticâ in the particular way we tested it in our case studies, not addressing concepts such as agency, power and decision-making. It was critiqued for not being specific to decisions about biodiversity and the related nature values.publishedVersio
Clinical and Laboratory Characteristics of Hyperprolactinemia in Children and Adolescents: National Survey
Conclusion: We present the largest cohort of children and adolescents with hyperprolactinemia in the literature to date. Hyperprolactinemia is more common in females and cabergoline is highly effective and practical to use in adolescents, due to its biweekly dosing. Indications for surgery in pediatric cases need to be revised
Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at âs = 13 TeV
Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (dÌ t) and chromomagnetic (ÎŒÌ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fbâ1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ÂŻ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ÂŻ final states. The values found for the parameters are AFB(1)=0.048â0.087+0.095(stat)â0.029+0.020(syst),ÎŒÌt=â0.024â0.009+0.013(stat)â0.011+0.016(syst), and a limit is placed on the magnitude of | dÌ t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.
MUSiC : a model-unspecific search for new physics in proton-proton collisions at root s=13TeV
Results of the Model Unspecific Search in CMS (MUSiC), using proton-proton collision data recorded at the LHC at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1), are presented. The MUSiC analysis searches for anomalies that could be signatures of physics beyond the standard model. The analysis is based on the comparison of observed data with the standard model prediction, as determined from simulation, in several hundred final states and multiple kinematic distributions. Events containing at least one electron or muon are classified based on their final state topology, and an automated search algorithm surveys the observed data for deviations from the prediction. The sensitivity of the search is validated using multiple methods. No significant deviations from the predictions have been observed. For a wide range of final state topologies, agreement is found between the data and the standard model simulation. This analysis complements dedicated search analyses by significantly expanding the range of final states covered using a model independent approach with the largest data set to date to probe phase space regions beyond the reach of previous general searches.Peer reviewe
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