437 research outputs found
Coronary microvascular disease in hypertrophic and infiltrative cardiomyopathies
Pathologic hypertrophy of the cardiac muscle is a commonly encountered phenotype in clinical practice, associated with a variety of structural and non-structural diseases. Coronary microvascular disease is considered to play an important role in the natural history of this pathological phenotype. Non-invasive imaging modalities, most prominently positron emission tomography and cardiac magnetic resonance, have provided insights into the pathophysiological mechanisms of the interplay between hypertrophy and the coronary microvasculature. This article summarizes the current knowledge on coronary microvascular dysfunction in the most frequently encountered forms of pathologic hypertrophy.
Keywords: CMD; CMR; Coronary microvascular disease; cardiac PET; coronary flow reserve; left ventricular hypertrophy
Semantic Integration of Cervical Cancer Data Repositories to Facilitate Multicenter Association Studies: The ASSIST Approach
The current work addresses the unifi cation of Electronic Health Records related to cervical cancer into a single medical knowledge source, in the context of the EU-funded ASSIST research project. The project aims to facilitate the research for cervical precancer and cancer through a system that virtually unifi es multiple patient record repositories, physically located in different medical centers/hospitals, thus, increasing fl exibility by allowing the formation of study groups “on demand” and by recycling patient records in new studies. To this end, ASSIST uses semantic technologies to translate all medical entities (such as patient examination results, history, habits, genetic profi le) and represent them in a common form, encoded in the ASSIST Cervical Cancer Ontology. The current paper presents the knowledge elicitation approach followed, towards the defi nition and representation of the disease’s medical concepts and rules that constitute the basis for the ASSIST Cervical Cancer Ontology. The proposed approach constitutes a paradigm for semantic integration of heterogeneous clinical data that may be applicable to other biomedical application domains
Evaluation of multivalency as an organization principle for the efficient synthesis of doubly and triply threaded amide rotaxanes
Mono-, di- and trivalent pseudorotaxanes with tetralactam macrocycle hosts and
axles containing diamide binding stations as the guests have been synthesised.
Their threading behaviour was analyzed in detail by NMR experiments and
isothermal titration calorimetry. An X-ray crystal structure of the monovalent
pseudorotaxane confirms the binding motif. Double mutant cycle analysis
provides the effective molarities and insight into the chelate cooperativity
of multivalent binding. While the second binding event in a trivalent
pseudorotaxane exhibits a slightly positive cooperativity, the third binding
is nearly non-cooperative. Nevertheless, the enhanced binding affinities
resulting from the multivalent interaction are the basis for a highly
efficient synthesis of di- and trivalent rotaxanes through stoppering the axle
termini by “click” chemistry. Evidence for the multiply threaded geometry
comes from NMR spectroscopy as well as tandem mass-spectrometric fragmentation
experiments of mass-selected rotaxane ions in the gas phase. Furthermore, the
trivalent rotaxane can be controlled by external stimuli (chloride addition
and removal) which lead to an elevator-type movement of the wheel along the
axle
A quantitative analysis of stratospheric HCl, HNO3, and O3 in the tropopause region near the subtropical jet
The effects of chemical two-way mixing on the Extratropical Transition Layer (ExTL) near the
subtropical jet are investigated by stratospheric tracer-tracer correlations. To this end, in situ measurements
were performed west of Africa (25–32◦N) during the Transport and Composition of the Upper Troposphere
Lower Stratosphere (UTLS)/Earth System Model Validation (TACTS/ESMVal) mission in August/September
2012. The Atmospheric chemical Ionization Mass Spectrometer sampling HCl and HNO3 was for the first
time deployed on the new German High Altitude and Long range research aircraft (HALO). Measurements
of O3, CO, European Centre for Medium-Range Weather Forecasts (ECMWF) analysis, and the tight
correlation of the unambiguous tracer HCl to O3 and HNO3 in the lower stratosphere were used to quantify
the stratospheric content of these species in the ExTL. With increasing distance from the tropopause, the
stratospheric content increased from 10% to 100% with differing profiles for HNO3 and O3. Tropospheric
fractions of 20% HNO3 and 40% O3 were detected up to a distance of 30 K above the tropopause
Dynamics of genotype-specific HPV clearance and reinfection in rural Ghana may compromise HPV screening approaches
Persistent Human Papillomavirus (HPV) infection is a prerequisite for cervical cancer development. Few studies investigated clearance of high-risk HPV in low-and-middle-income countries. Our study investigated HPV clearance and persistence over four years in women from North Tongu District, Ghana. In 2010/2011, cervical swabs of 500 patients were collected and HPV genotyped (nested multiplex PCR) in Accra, Ghana. In 2014, 104 women who previously tested positive for high-risk HPV and remained untreated were re-tested for HPV. Cytobrush samples were genotyped (GP5+/6+ PCR & Luminex-MPG readout) in Berlin, Germany. Positively tested patients underwent colposcopy and treatment if indicated. Of 104 women, who tested high-risk HPV+ in 2010/2011, seven (6,7%; 95%CI: 2.7-13.4%) had ≥1 persistent high-risk-infection after ~4 years (mean age 39 years). Ninety-seven (93,3%; 95%CI: 86.6-97.3%) had cleared the original infection, while 22 (21.2%; 95%CI: 13.8-30.3%) had acquired new high-risk infections with other genotypes. Persistent types found were HPV 16, 18, 35, 39, 51, 52, 58, and 68. Among those patients, one case of CIN2 (HPV 68) and one micro-invasive cervical cancer (HPV 16) were detected. This longitudinal observational data suggest that single HPV screening rounds may lead to over-referral. Including type-specific HPV re-testing or additional triage methods could help reduce follow-up rates
Short-term effects of video gaming on brain response during working memory performance
Breaks filled with different break activities often interrupt cognitive performance in everyday life. Previous studies have reported that both enhancing and deteriorating effects on challenging ongoing tasks such as working memory updating, depend on the type of break activity. However, neural mechanisms of these break-related alterations in working memory performance have not been studied, to date. Therefore, we conducted a brain imaging study to identify the neurobiological correlates of effects on the n-back working memory task related to different break activities. Before performing the n-back task in the magnetic resonance imaging (MRI) scanner, young adults were exposed to break activities in the MRI scanner involving (i) eyes-open resting, (ii) listening to music, and (iii) playing the video game “Angry Birds”. Heart rate was measured by a pulse oximeter during the experiment. We found that increased heart rate during gaming as well as decreased relaxation levels after a video gaming break was related to poorer n-back task performance, as compared to listening to music. On the neural level, video gaming reduced supplementary motor area activation during working memory performance. These results may indicate that video gaming during a break may affect working memory performance by interfering with arousal state and frontal cognitive control functions
Cross-sectional study on the impact of adverse childhood experiences on coronary flow reserve in male physicians with and without occupational burnout
OBJECTIVE
Physicians face documented challenges to their mental and physical well-being, particularly in the forms of occupational burnout and cardiovascular disease. This study examined the previously under-researched intersection of early life stressors, prolonged occupational stress, and cardiovascular health in physicians.
METHODS
Participants were 60 practicing male physicians, 30 with clinical burnout, defined by the Maslach Burnout Inventory, and 30 non-burnout controls. They completed the Adverse Childhood Experiences (ACE) Questionnaire asking about abuse, neglect and household dysfunctions before the age of 18, and the Perceived Stress Scale to rate thoughts and feelings about stress in the past month. Endothelium-independent (adenosine challenge) coronary flow reserve (CFR) and endothelium-dependent CFR (cold pressor test) were assessed by positron emission tomography-computed tomography. The segment stenosis score was determined by coronary computed tomography angiography.
RESULTS
Twenty-six (43%) participants reported at least one ACE and five (8%) reported ≥4 ACEs. A higher ACEs sum score was associated with lower endothelium-independent CFR (r partial (r) = -0.347, p = .01) and endothelium-dependent CFR (r = -0.278, p = .04), adjusting for age, body mass index, perceived stress and segment stenosis score. In exploratory analyses, participants with ≥4 ACEs had lower endothelium-independent CFR (r = -0.419, p = .001) and endothelium-dependent CFR (r = -0.278, p = .04), than those with <4 ACEs. Endothelium-dependent CFR was higher in physicians with burnout than in controls (r = 0.277, p = .04). No significant interaction emerged between burnout and ACEs for CFR.
CONCLUSION
The findings suggest an independent association between ACEs and CFR in male physicians and emphasize the nuanced relationship between early life stressors, professional stress, and cardiovascular health
Atherosclerosis of the iliac arteries for the prediction of erectile dysfunction and epistaxis in men undergoing abdominal CT scan
BACKGROUND: To investigate the association between erectile dysfunction (ED) as well as epistaxis (ES) in relation to the extent of iliac atherosclerosis.
METHODS: In this retrospective cross-sectional study, all consecutive male patients treated at our institution from 01/2016 to 12/2020 undergoing abdominal CT scan were evaluated. Patients (n = 1272) were invited by mail to participate in the study in returning two questionnaires for the evaluation of ED (IIEF-5) and ES. Patients who returned filled-in questionnaires within a 3-month deadline were included in the study. The extent of atherosclerosis in the common iliac artery (CIA) and the internal iliac artery (IIA) was assessed by calcium scoring on unenhanced CT. Stratification of results was performed according to reported IIEF-5 scores and consequential ED groups.
RESULTS: In total, 437 patients (34.4% of contacted) met the inclusion criteria. Forty-two patients did not fulfill predefined age requirements (< 75 years) and 120 patients had to be excluded as calcium scoring on nonenhanced CT was not feasible. Finally, 275 patients were included in the analysis and stratified into groups of "no-mild" (n = 146) and "moderate-severe" (n = 129) ED. The calcium score (r=-0.28, p < 0.001) and the number of atherosclerotic lesions (r=-0.32, p < 0.001) in the CIA + IIA showed a significant negative correlation to the IIEF-5 score, respectively. Patients differed significantly in CIA + IIA calcium score (difference: 167.4, p < 0.001) and number of atherosclerotic lesions (difference: 5.00, p < 0.001) when belonging to the "no-mild" vs. "moderate-severe" ED group, respectively. A multivariable regression model, after adjusting for relevant baseline characteristics, showed that the number of atherosclerotic CIA + IIA lesions was an independent predictor of ED (OR = 1.05, p = 0.036), whereas CIA + IIA calcium score was not (OR = 1.00031, p = 0.20). No relevant correlation was found between ES episodes and IIEF-5 scores (r=-0.069, p = 0.25), CIA + IIA calcium score (r=-0.10, p = 0.87) or number of atherosclerotic CIA + IIA lesions (r=-0.032, p = 0.60), respectively.
CONCLUSIONS: The number of atherosclerotic lesions in the iliac arteries on nonenhanced abdominal CT scans is associated with the severity of ED. This may be used to identify subclinical cardiovascular disease and to quantify the risk for cardiovascular hazards in the future
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