Chirurgische behandeling complexe vormen van mitralisklepinsufficiëntie

Promotie Wobbe Bouma ​Wanneer de hartklep tussen de linkerboezem en de linkerkamer van het hart ernstige lekkage vertoont door degeneratieve …

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Waarschuwingssignaal verantwoordelijk voor falen celtransplantatie

Voor onder andere patiënten met diabetes type 1 zou het een uitkomst kunnen zijn: het inkapselen van insulineproducerende donorcellen om ze zo al …

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Pleidooi voor discipline overstijgende samenwerking in obesitas onderzoek

​ Promotie Roel van der Heijden Het eten van te veel dierlijk vet of voeding met te hoge concentraties cholesterol kunnen beide bijdragen aan een …

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Eerste duizend dagen cruciaal voor preventie overgewicht

​Leanne Küpers: The first 1000 days and beyond Zo’n duizend dagen zitten er tussen de conceptie en de tweede verjaardag. Deze periode blijkt van …

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Vorm kroon maakt geen verschil voor kwaliteit tandvlees

Ratnadeep Patil: Soft tissue development in the esthetic zone Implantaatleveranciers zullen het betreuren, maar de aanname blijkt onjuist. Tandarts …

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Onderzoek naar rol CNDP1-gen in ontstaan diabetische nierschade

​ Promotie Shiqi Zhang Hemodialysepatiënten die voor het CNDP1-gen (een gen dat in verband wordt gebracht met nierschade door diabetes) twee gelijke …

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Prognostische biomarkers voor behandeling hoofdhalskanker

​ Promotie Wouter Pattje Het tumor-onderdrukkende gen Phosphotase-and-Tensin-Homologue (PTEN) en het eiwit gefosforyleerd Associated-Death-Domain …

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Respons op behandeling niet-kleincellige longtumor eerder meetbaar

Promotie Gerald Kerner Met een speciale PET-tracer is het mogelijk om het zuurstofgehalte binnen niet-kleincellige longtumoren te meten. Dat stelden …

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Inwoners Sardinië helpen toekomstig genetisch onderzoek vooruit

Promotie Serena Sanna Steeds meer vrijwilligers stellen hun genoom (de complete set van genen en chromosomen waaruit wij bestaan) beschikbaar voor …

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Non-invasieve hemodynamische metingen in de initiële fase op de SEH bij sepsis en niet sepsispatiënten : een pilotstudie

Sepsis is a clinical syndrome with a high prevalence in the emergency department. It is known as a complicated, systemic infection and the hemodynamic parameters are often highly inconsistent. Noteworthy is that the blood pressure often drops significantly, despite administering fluid therapy. By administrating fluid therapy, it is expected that the blood pressure either increases or remains constant. No golden standard exists for administrating fluid, and the amount of fluid is often empirically determined. It is important to know the spontaneous course of hemodynamic parameters, in order to accurately determine what the effect of fluid therapy will be and how much fluid should be administered. The NICOM measures stroke volume and cardiac output in a fast and non-invasive manner, these parameters play an important role in assessing the state of resuscitation of the patient. Furthermore, it becomes possible to investigate whether and how parameters used as diagnostic criteria for sepsis change when the hemodynamic parameters are being recorded. Also, the effect of fluid therapy on changes in the parameters can be studied.
Objective:
Registration of various hemodynamic and clinical parameters (including NICOM) in the emergency department, on both septic and non-septic patients, as well as the effect of fluid therapy on these parameters.
Methods:
During a period of 19 weeks, all patients admitted to the emergency department doctor or internal medicine were screened and divided in groups with either septic patients or non-septic patients. Screening for septic patients was carried out by using the Systemic Inflammatory Response Syndrome-criteria. Hemodynamic parameters were measured during the first hour after arrival on the emergency department. Some patients were connected to the NICOM, enabling stroke volume and cardiac output monitoring.
Results:
The hemodynamic measurements were useful with 106 patients. With 29 of these patients NICOM results were retrieved successfully. 3 patients presented with septic shock, another 3 patients presented with severe sepsis, and 25 patients presented with sepsis. After the initial hour there was a significant decrease in blood pressure and heart rate, both in septic and non-septic patients. Also at the baseline there were significant differences between septic and non-septic patients.
Conclusion:
The course of the hemodynamic parameters blood pressure and heart rate shows a spontaneous drop, regardless of the presence of sepsis and the amount of fluid therapy administered. For that reason, blood pressure and heart rate do not appear to be appropriate parameters to guide fluid therapy. It appears that in patients with a high heart rate, more fluid is being administered. A high heart rate is associated with a low stroke volume. It is possible that the decision to adjust fluids depends on a high heart rate.

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Influence of position on pelvic floor anatomy, with and without pelvic muscle contraction : A study with 3D perineal ultrasound in women with urge-incontinence

Objective
The objective of this study is to understand more of the anatomical changes that happen to the pelvic anatomy with position change (supine, sitting and standing), with and without pelvic floor contraction. Our main measurements are hiatal area, width and length. Secondary outcome measurements are levator urethral gap and urethral blood flow (resistance- and pulsatile index).
Methods
Measurements were taken with perineal 3D-ultrasound in 11 volunteers with urge-incontinence, with no prolaps or pelvic surgery. Volunteers started in rest in supine position followed by pelvic floor contraction, blood flow was measured last. After supine volunteers sat up and measurements where repeated and again in standing position, without blood flow measurements.
Results
Hiatal area reduced significantly in supine and standing position with pelvic floor contraction in supine position from 14.63 to 12.29 cm2 and in standing position from 16.27 to 14.49 cm2. The hiatal area during contraction did not significantly change in the sitting position; it went from average 14.44 to 13.66 cm2. The mean length of the hiatus in supine position decreased with contraction from 5.32 to 4.71 cm, in sitting position from 5.37 to 4.99 cm and in standing position from 5.66 to 5.06 cm. Pelvic floor contraction gave a significant length reduction in supine and standing position, however no significance in sitting position. The width decreased wile contracting from 4.01 to 3.66 cm in supine position, 3.86 to 3.75 cm in sitting position and increased from 3.97 to 3.99 cm in standing position, where only supine position was significant. The hiatal area decreased from supine to sitting position and increased in standing position, with no significant difference. With pelvic floor contraction the hiatal area increased from supine, to sitting and standing, with no significant differences between the groups. The length in rest and with contraction increases from supine to sitting to standing. The width in rest and with pelvic floor contraction has no significance difference in different positions. The difference in width with and without contraction is significant between supine and standing. Blood flow shows a decrease in pulsatile index from supine to sitting (7,1 to 5,1) and decrease of resistance index from 1,1 to 1,0.
Conclusion
From the data we collected we can conclude that in women with urge incontinence there are no significant changes in hiatal area, length or width with change in position, either in rest or with pelvic floor muscle exercise. Data however shows a trend that hiatal area increases from the supine to the standing position, both at rest and with pelvic muscle contraction, likely due to the effect of gravity on the pelvic organs. The smaller change in hiatal area with pelvic floor contraction in the standing and sitting position suggests that pelvic muscle contractions are less able to counter the effect of gravity in the standing and sitting position than in the supine position.

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Congenital Vascular Rings : An Exploratory Study in Adult Patients

Introduction. Vascular rings are rare congenital vascular anomalies, surrounding the
trachea and/or esophagus, causing variable degrees of compression and giving rise to a wide
range of symptoms that vary in severity and age at presentation. Due to the aspecific
complaints and the presence of associated cardiac anomalies, the diagnosis is challenging.
The aim of this study was to describe the different types of vascular rings according to their
anatomical heterogeneity, presenting symptoms, used diagnostic strategies and (long-term)
surgical outcome, in order to raise clinical awareness of this complex congenital anomaly and
its diagnostic and treatment strategies.
Methods. A retrospective observational database study was conducted, reviewing the
electronic and paper medical charts of patients from seven academic centers, identified from
the CONCOR database. The type of vascular ring was classified according to the categories
by Backer and Mavroudis. Descriptive statistics were applied.
Results. 69 patients were included with a median age at presentation of 8.5 years
(range 0 – 53 years). 21 patients (30.4%) had a double aortic arch, 16 patients (23.2%) a right
aortic arch with aberrant left subclavian artery, 30 patients (43.5%) a left aortic arch with
aberrant right subclavian artery, 1 patient (1.4%) an innominate artery compression and 1
patient (1.4%) a right cervical aortic arch. Associated cardiac anomalies were found in 63.8%
of patients. Main symptomatology were respiratory symptoms (82.9%), with dyspnea being
most frequent (86.2%). Dysphagia was the most common gastro-intestinal symptom (69.2%).
Chest radiography was the most frequent obtained diagnostic strategy (85.5%). Barium
esophagography, chest CT- and MRI scan were diagnostic in most cases (90%, 100% and
88.9%, respectively). Spirometry showed a variable intrathoracic obstruction, suggestive for a
vascular ring. Surgery was performed in 42% of patients with a median age of 17 years. A left
thoracotomy was the most performed type of surgery (55.2%). The median length of followup
after surgery was 5 years. 93% of patients showed (some) improvement or complete relief
of symptoms shortly after surgery.
Conclusion. With this retrospective observational database study, recognition of
several useful clinical points concerning vascular rings in the CONCOR database population
was obtained, increasing clinical awareness of this condition and its diagnostic and treatment
strategies.

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Gebruik van de (in) fertility chip voor semenanalayse na vasectomie :Kan dit microfluïdische systeem in de toekomst de gouden standaard vervangen?

Introduction: Approximately 42 million couples worldwide use vasectomy as their means of birth control and family planning. After the vasectomy has been performed, these men need to use other forms of contraception until 12 weeks later their semen has been analysed. This post-vasectomy semenanalysis is carried out by laboratory technicians who use a special counting chamber and a microscope to optically check for remaining sperm cells in the ejaculate. This test is expensive and time-consuming. Twente University developed in 2011 a prototype system which could be used to perform post-vasectomy semenanalysis. The microfluidic system utilises a glass chip with a nano-sized channel etched into it. Fluids like semen can be pumped through this channel and can be analyzed at the same time. This new test method we propose could make the analysis less expensive, more reliable and could possibly be performed closer to the patients home, for example in an outpatient clinic or GP’s office. Methods: First the prototype was calibrated using solutions with known concentrations of polystyrene beads and boar semen. Correlation between the results of the old and the new test method were evaluated. We then tested 7 semen samples from males who have had a vasectomy and analysed the results, looking for a correlation. Results: We have established the optimal flowrate and threshold for fluids to be pumped through the chip. For beads this was a flowrate of 0.25 μl/min and a threshold of 0.3 V. The coefficient of determination for beads was 0.94. We were not able to find any correlation between the results of the old and the new test method when testing boar semen or human ejaculate. Conclusion: This first prototype of the (in)fertility chip was able to detect polysterene beads, but analysis of boar- and human semen was disturbed by electromagnetic interference and sensitivity for shocks. Furthermore, the current prototype was unable to differentiate between spermcells and epithelial cells, erythrocytes and lymfocytes. Recommendations proposed in this paper will help further testing of boar and human semen in the future.

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Survival following cardiac arrest in the neonatal intensive care unit

Introduction. Resuscitations performed in neonatal intensive care units (NICUs) are sparsely studied, in contrast to resuscitation in delivery rooms and paediatric intensive care units (PICUs), where it is shown that duration of resuscitation, location of arrest, age, heart rhythm, and medications administered affect survival. Outcomes of resuscitation and variables that affect outcome might be different in the NICU, because the pathophysiology of the patients is different than in delivery rooms or PICUs. The objectives of this study are to quantify and characterize in-unit resuscitations in a referral NICU and to identify the infant and event characteristics associated with survival after these resuscitations.
Methods. A retrospective cohort study of resuscitations performed from January 1, 2011 to June 30, 2015, in the NICU of the Children’s Hospital of Philadelphia (CHOP). Eligible patients were identified from CHOP Resuscitation database. Data was abstracted from several resuscitation databases. Survival to hospital discharge was our outcome. Relations between outcome and patient/resuscitation-related variables were examined with multivariable logistic regressions.
Results. During the study period, 94 first time events treated with chest compressions were abstracted from the database. Median duration of chest compression was 2 minutes, with outliers at 52 minutes. Multivariate analysis showed low pH prior to event, blood pressure support medication before the event and epinephrine administration during resuscitation being associated with mortality.
Conclusion. Resuscitation in infants at referral NICUs is rare and has a low mortality. Results are still hypothesis generating and further studies are needed to identify methods to improve survival.

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Predicitive Value of Quantitative Coronary Analysis for Intraoperative Flow Measurements and Fractional Flow Reserve in Isolated Off-pump Coronary Artery Surgery

Background: Preoperative quantitative coronary analysis (QCA) and intraoperative graft flow measurements may be of value in predicting competitive flow.
Objectives: To assess the predictive value of preoperative severity of coronary stenoses measured by QCA for intraoperative flow measurements as mean flow (MF), pulsatility index (PI) and backward flow (%BF) in patients undergoing off-pump coronary artery bypass (OPCAB) surgery. Our aim is to create a preoperative risk model for competitive flow. Secondary, we evaluated QCA to predict fractional flow reserve (FFR) and we compared visual estimated lesion severity with QCA-derived degree of stenosis.
Methods: Seventy-two patients underwent OPCAB surgery with a left internal mammary artery (LIMA) graft to left anterior descending artery (LAD) and intraoperative graft flow measurements from September 2012 till August 2014. Degree of stenosis was measured with QCA and FFR, and was visually assessed. We investigated the correlation between QCA and intraoperative flow measurements, between QCA and FFR and between lesion severity by visual inspection and QCA.
Results: Neither MF and PI, nor %BF showed a significant correlation with preoperative degree of stenosis. No significant correlation was found between 33 FFR measurements and QCA. A moderate to good significant correlation was found between visual inspection and QCA-derived degree of stenosis in the left main coronary artery and the proximal LAD (r-values of 0.699 and 0.509, respectively). There was a trend towards a significant correlation in the mid LAD (r = 0.197, P = 0.079).
Conclusions: The principal finding of this study is that QCA is not a clear predictor for intraoperative flow measurements and FFR. Visual assessment tends to overestimate the degree of stenosis compared with QCA. Therefore, it remains important to perform FFR in clinical decision-making. Hemodynamic parameters need to be taken into account in future research with larger series of data.

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Predicitive value of Quantitative Coronary Analysis for Intraoperative Flow Measurements and Fractional Flow Reserve : In Isolated Off-pump Coronary Artery Surgery

Background: Preoperative quantitative coronary analysis (QCA) and intraoperative graft flow measurements may be of value in predicting competitive flow.
Objectives: To assess the predictive value of preoperative severity of coronary stenoses measured by QCA for intraoperative flow measurements as mean flow (MF), pulsatility index (PI) and backward flow (%BF) in patients undergoing off-pump coronary artery bypass (OPCAB) surgery. Our aim is to create a preoperative risk model for competitive flow. Secondary, we evaluated QCA to predict fractional flow reserve (FFR) and we compared visual estimated lesion severity with QCA-derived degree of stenosis.
Methods: Seventy-two patients underwent OPCAB surgery with a left internal mammary artery (LIMA) graft to left anterior descending artery (LAD) and intraoperative graft flow measurements from September 2012 till August 2014. Degree of stenosis was measured with QCA and FFR, and was visually assessed. We investigated the correlation between QCA and intraoperative flow measurements, between QCA and FFR and between lesion severity by visual inspection and QCA.
Results: Neither MF and PI, nor %BF showed a significant correlation with preoperative degree of stenosis. No significant correlation was found between 33 FFR measurements and QCA. A moderate to good significant correlation was found between visual inspection and QCA-derived degree of stenosis in the left main coronary artery and the proximal LAD (r-values of 0.699 and 0.509, respectively). There was a trend towards a significant correlation in the mid LAD (r = 0.197, P = 0.079).
Conclusions: The principal finding of this study is that QCA is not a clear predictor for intraoperative flow measurements and FFR. Visual assessment tends to overestimate the degree of stenosis compared with QCA. Therefore, it remains important to perform FFR in clinical decision-making. Hemodynamic parameters need to be taken into account in future research with larger series of data.

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The Canonical and Accessory Sec System of Gram-positive Bacteria.

The Canonical and Accessory Sec System of Gram-positive Bacteria.

Curr Top Microbiol Immunol. 2016 May 7;

Authors: Prabudiansyah I, Driessen AJ

Abstract
The Sec system is present in all bacteria and responsible for the translocation of the majority of proteins across the cytoplasmic membrane. The system consists of two principal components: the ATPase motor protein, SecA, and the protein-conducting channel, SecYEG. In addition to this canonical Sec system, several Gram-positive bacteria also possess a so-called accessory Sec system. This is a specialized translocation system that is responsible for the export of a subset of secretory proteins, including virulence factors. The accessory Sec system consists of a second SecA paralog, termed SecA2, with or without a second SecY paralog, termed SecY2. In some bacteria, the accessory Sec system is dependent on the canonical Sec system for functionality, while in other bacteria, they can function independently. In this review, we provide an overview of the current knowledge of the canonical and accessory Sec system of Gram-positive bacteria with a focus on the primary component of the Sec translocase, SecA and SecYEG.

PMID: 27154227 [PubMed – as supplied by publisher]

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Frequency selectivity of the human cochlea: Suppression tuning of spontaneous otoacoustic emissions.

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Frequency selectivity of the human cochlea: Suppression tuning of spontaneous otoacoustic emissions.

Hear Res. 2016 Apr 29;

Authors: Manley GA, van Dijk P

Abstract
Frequency selectivity is a key functional property of the inner ear and since hearing research began, the frequency resolution of the human ear has been a central question. In contrast to animal studies, which permit invasive recording of neural activity, human studies must rely on indirect methods to determine hearing selectivity. Psychophysical studies, which used masking of a tone by other sounds, indicate a modest frequency selectivity in humans. By contrast, estimates using the phase delays of stimulus-frequency otoacoustic emissions (SFOAE) predict a remarkably high selectivity, unique among mammals. An alternative measure of cochlear frequency selectivity are suppression tuning curves of spontaneous otoacoustic emissions (SOAE). Several animal studies show that these measures are in excellent agreement with neural frequency selectivity. Here we contribute a large data set from normal-hearing young humans on suppression tuning curves (STC) of spontaneous otoacoustic emissions (SOAE). The frequency selectivities of human STC measured near threshold levels agree with the earlier, much lower, psychophysical estimates. They differ, however, from the typical patterns seen in animal auditory nerve data in that the selectivity is remarkably independent of frequency. In addition, SOAE are suppressed by higher-level tones in narrow frequency bands clearly above the main suppression frequencies. These narrow suppression bands suggest interactions between the suppressor tone and a cochlear standing wave corresponding to the SOAE frequency being suppressed. The data show that the relationship between pre-neural mechanical processing in the cochlea and neural coding at the hair-cell/auditory nerve synapse needs to be reconsidered.

PMID: 27139323 [PubMed – as supplied by publisher]

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Erratum: Factors limiting vocal-tract length discrimination in cochlear implant simulations [J. Acoust. Soc. Am. 137(3), 1298-1308 (2015)].

Erratum: Factors limiting vocal-tract length discrimination in cochlear implant simulations [J. Acoust. Soc. Am. 137(3), 1298-1308 (2015)].

J Acoust Soc Am. 2016 Apr;139(4):1734

Authors: Gaudrain E, Başkent D

PMID: 27106320 [PubMed – in process]

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Relation between CYP2D6 Genotype, Phenotype and Therapeutic Drug Concentrations among Nortriptyline and Venlafaxine Users in Old Age Psychiatry.

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Relation between CYP2D6 Genotype, Phenotype and Therapeutic Drug Concentrations among Nortriptyline and Venlafaxine Users in Old Age Psychiatry.

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