From cardiogenesis to cardiac regeneration : focus on epicardium-derived cells

Embryonic EPDCs are crucial for proper myocardial architecture and coronary vessel formation, both through their physical contribution and their regulatory role in these developmental processes. This thesis reports for the first time on the role of Epicardium-Derived Cells (EPDCs) in the adult ischemic heart. It is demonstrated that transplanted adult EPDCs, isolated from human adult epicardial tissue, improve left ventricular function of the ischemic mouse heart. This is probably instigated by an early paracrine-mediated stimulation of the injected EPDCs on the surrounding host tissue, as indicated by increased wall thickness, augmented vascular density (mouse origin), and enhanced DNA-damage repair activity of the endogenous tissue. Cardiac healing in the EPDC-recipients is further characterized by advanced WT-1 expression, a marker for undifferentiated EPDCs, indicating induction of endogenous epicardial activity. Strikingly, the benefit of EPDC injection can be further enhanced by adding complementary cardiomyocyte progenitor cells to the EPDC transplant, explained by synergistic paracrine actions of the two different cell types. Two different techniques for assessment of left ventricular function in the post-infarct failing mouse heart are evaluated. It is shown that both conductance catheter and magnetic resonance imaging are reliable methods, each having specific unique features which need to be considered during experimental set-up.UBL - phd migration 201

Rwzi-effluent gebruiken voor vismigratie

Zeewaarts migrerende schieralen laten een gedragsverandering zien wanneer zij geconfronteerd worden met een lozingspluim van rwzi-effluent. Ruim de helft van de vissen verandert van zwemrichting en tracht langs de rand van de pluim te passeren. Het risico dat een permanente migratiebarrière ontstaat is bij de meeste rwzi's niet groot door het dynamische karakter van de lozingspluim. Bij rwzi's die lozen op wateren met een beperkt afvoerdebiet, kunnen wel migratiebarrières ontstaan, maar met relatief eenvoudige aanpassingen kan de kans daarop worden verkleind. De onderzoeksresultaten geven aan dat rwzi-effluentpluimen potentie hebben om te worden ingezet voor de geleiding van stroomafwaarts migrerende vissen naar een veilige route langs gevaarlijke situaties zoals koelwaterinlaten, gemalen en waterkrachtcentrales

Complete Weight Enumerators of Generalized Doubly-Even Self-Dual Codes

For any q which is a power of 2 we describe a finite subgroup of the group of invertible complex q by q matrices under which the complete weight enumerators of generalized doubly-even self-dual codes over the field with q elements are invariant. An explicit description of the invariant ring and some applications to extremality of such codes are obtained in the case q=4

Prestrain relaxation in non-covalently modified ethylene-vinyl acetate | PyChol | multiwall carbon nanotube nanocomposites

Effects of aging on chemical structure and molecular dynamic behaviour of strained thermally active ethylene-vinyl acetate | multiwall carbon nanotube (EVA|MWCNT) composites were investigated by spectroscopy and microscopy techniques. Aged composites showed spatial inhomogeneity due to system relaxation. Inhomogeneity is attributed to segregation of non-covalently linked cholestryl 1-pyrenecarboxylate, acting as MWCNT dispersant and polymer compatibilizer. Analysis of molecular interplay between filler and matrix upon in situ temperature variation showed a lack of synchronicity, which had been observed in fresh composites. Reduced synchronous interplay allowed quantification of degraded π-π interactions, promoting PyChol unlatching as a result of both sonication and strained-derived π-π degradation

Maximal and submaximal cardiopulmonary responses to whole-body simulated swimming

The purpose of this study was to explore the relationship between oxygen uptake and heart rate in response to whole-body simulated swimming. Nine club swimmers (mean ± SD; age: 20 ± 4 years, stature: 1.68 ± 11 m, mass: 63 ± 12 kg) signed an informed consent and participated in the study. All subjects performed a simulated front crawl combined arm-pulling and leg-kicking incremental exercise test to exhaustion using a swim bench and a leg-kicking ergometer. Oxygen uptake (VO2) and heart rate (HR) were recorded at 15 s intervals and at exhaustion (VO2peak; HRpeak). The HR at ventilatory threshold (VT) was determined (VTHR) and the VO2/HR relationship explored. The mean ± SD for VO2peak and HRpeak values were 3.3 ± 0.4 L·min-1 and 174 ± 8 b·min-1 respectively, whereas VTHR occurred at 162 ± 5 b·min-1 at a predicted VO2 of 2.4 ± 0.4 L·min-1. The relationship between VO2 and HR was shown to be linear in all subjects (r=0.94; P<0.05). Previously published data have demonstrated linear relationships between HR/EI and VO2/EI (r=0.99 and r=0.98 respectively; P<0.05) for simulated arm-pulling exercise. The peak values for simulated front-crawl arm-pulling and leg-kicking exercise were: 2.85 ± 0.26 L·min-1, 171 ± 3 b·min-1 and 3.1 L·min-1, 170 ± 3 b·min-1, respectively. Our results suggest that the VO2 and HR responses to full-stroke simulated swimming are higher than the respective responses to arm-pulling or leg-kicking separately. This type of whole-body ergometry might be useful for assessing maximal and submaximal cardiopulmonary responses to exercise in swimmers

Behavioural response of silver eel to effluent plumes: Telemetry experiments

Fish migration may be hampered by a range of physical barriers. That non-physical barriers such as sudden changes in water quality may also serve as barriers is often stated, but only very few studies address this issue. This study focusses on linking the behavioural response of silver eel and river lamprey when encountering a waste water plume (effluent) in field situations. Individual fish movements were tracked by means of acoustic telemetry in 2D (in 2009) and in 3D (in 2010) at a location surrounding a waste water outlet in the Eems-canal near Groningen. Plume dynamics were modelled and calibrated by Deltares and used to directly link to individual movement patterns of fish. In both years, 20 silver eels (downstream migration) were tagged and in 2009 also 13 rvier lamprey (upstram migration) were tagged. In total, 37 out of 40 silver eels entered the 2D – 3D study site. Of these, 57 % showed avoidance behaviour when encountering the plume, 43 % were indifferent to the plume and no attraction to the plume was observed. Avoidance behaviour varied from moving away from the plume but continuing the migration, to returning and not be detected again, thereby possibly ceasing their migration (3 out of 37). This indicates that waste water plumes may serve as non-physical barriers to migrating silver eel. Given the very dynamic nature of the plume in Groningen, even if waste water plumes serve as non-physical barriers for some of the migrating eels, numerous migratory windows are available in time and in water depths, when the plume is minimal or limited to one shore. Therefore it is estimated that the barrier effect of waste water plumes might be small, although delays in migration are likely to occur. Our findings may be used for management purposes. The occurrence of a behavioural avoidance response of approximately half of the eels opens up the possibility to manipulate plumes in order to ‘steer’ silver eels to a preferred direction, e.g. away from potential hazardous locations

Osteoporosis treatment with anti-sclerostin antibodies-mechanisms of action and clinical application

Osteoporosis is characterized by reduced bone mass and disruption of bone architecture, resulting in increased risk of fragility fractures and significant long-term disability. Although both anti-resorptive treatments and osteoanabolic drugs, such as parathyroid hormone analogues, are effective in fracture prevention, limitations exist due to lack of compliance or contraindications to these drugs. Thus, there is a need for novel potent therapies, especially for patients at high fracture risk. Romosozumab is a monoclonal antibody against sclerostin with a dual mode of action. It enhances bone formation and simultaneously suppresses bone resorption, resulting in a large anabolic window. In this opinion-based narrative review, we highlight the role of sclerostin as a critical regulator of bone mass and present human diseases of sclerostin deficiency as well as preclinical models of genetically modified sclerostin expression, which led to the development of anti-sclerostin antibodies. We review clinical studies of romosozumab in terms of bone mass accrual and anti-fracture activity in the setting of postmenopausal and male osteoporosis, present sequential treatment regimens, and discuss its safety profile and possible limitations in its use. Moreover, an outlook comprising future translational applications of anti-sclerostin antibodies in diseases other than osteoporosis is given, highlighting the clinical significance and future scopes of Wnt signaling in these settings.Diabetes mellitus: pathophysiological changes and therap

DIDSON observaties van gedrag van vis rond lozingspluimen

Binnen het project 'een pluim voor vismigratie’ zijn twee technieken toegepast om het gedrag van vis rond lozingspunten te onderzoeken: telemetrisch en akoestisch. Bij het telemetrisch onderzoek worden (lokaal) gevangen vissen van kleine zenders voorzien en teruggeplaatst in het water. Elke zender zend met regelmaat een uniek signaal uit dat door strategisch onder water opgestelde ontvangers kan worden opgevangen. Wanneer een signaal door meerdere ontvangers wordt opgevangen kan door middel van een kruispeiling de positie van de vis worden bepaald. Het voordeel van deze methode is dat individuele vissen voor een langere periode over een groot gebied kunnen worden gevolgd. Nadelen zijn: dat de te volgen vis vooraf een (beperkte) operatie moet ondergaan; dat het aantal individuele vissen dat kan worden gevolgd beperkt is; en dat te kleine vis niet met een zender kan worden uitgerust. Bovendien zijn de materiaalkosten (m.n. de zenders) van dit type onderzoek erg hoog en is de uitwerking van de data specialistisch en tijdrovend. Voor de akoestische methode wordt gebruikgemaakt van een akoestische camera, waarmee ook in troebel water en ’s nachts onder water opnames gemaakt kunnen worden. De kwaliteit van de beelden is dusdanig dat soorten doorgaans kunnen worden onderscheiden en ook een schatting van de lengte van de vis mogelijk is. Op deze wijze kan een goede indruk worden verkregen van het gedrag van de lokale visgemeenschap, zonder dat de vis daadwerkelijk ‘gehanteerd’ hoeft te worden. Ook kleine vis(soorten) zijn met deze techniek zichtbaar. Na aanschaf van de camera zijn de kosten van het onderzoek beperkt. Het gezichtsveld van de akoestische camera is echter beperkt waardoor het niet mogelijk is individuele vissen gedurende een langere periode te volgen. Dit rapport presenteert de resultaten van het akoestisch onderzoek van visgedrag bij een aantal lozingspluimen (bij drie rioolzuiveringsinstallaties en een poldergemaal) met een akoestische camera (de DIDSON) opgenomen zijn. Het doel van de DIDSON metingen was te onderzoeken of vissen in of nabij een lozingspluim afwijkend/vermijdend gedrag vertonen. In de bijlagen van dit rapport zijn de waarnemingen in tabelvorm opgenomen. Tevens zijn ter illustratie enkele opvallende beelden weergegeven, zoals deze met de DIDSON zijn gemaakt

Hypercalcemia during pregnancy: management and outcomes for mother and child (Oct, 10.1007/s12020-021-02615-2, 2021)

Diabetes mellitus: pathophysiological changes and therap

Sternocostoclavicular hyperostosis: positive clinical and radiological response on pamidronate

BackgroundSternocostoclavicular hyperostosis (SCCH) is a rare disease, constituting a chronic sterile osteomyelitis with elevated bone turnover in the axial skeleton, causing pain and shoulder dysfunction. SCCH severely interferes with daily activities, work, and quality of life. SCCH has a relapse-remitting disease course, but inflammatory-induced sclerotic transformation in the affected area is slowly progressive. Here we present two patients with clinical and radiological diagnosis of SCCH treated with intravenous pamidronate, leading to clinical remission in both, but complete resolution of sclerosis in one of them, which is a novel finding in our experience.Case PresentationTwo adult female SCCH-patients presented with longstanding pain, swelling of the anterior chest wall, and compromised shoulder function. Subsequent single photon emission computed tomography-computed tomography (SPECT/CT) illustrated elevated bone activity and sclerosis in the SC region, with hyperostosis, confirming the diagnosis of SCCH. As symptoms in both patients were eventually refractory to standard painkillers such as non-steroidal anti-inflammatory drugs (NSAIDs), intravenous pamidronate treatment in 3-month cycles was started. Pamidronate was effective in reducing pain and improving shoulder function and also led to decreased bone turnover on skeletal scintigraphy. Sclerosis in the first patient persisted. In the second patient, however, a complete resolution of sclerosis was observed.ConclusionsSCCH remains a rare bone disorder for which no evidence-based therapies are yet available. While disease burden is high, SCCH lacks recognition and is often diagnosed long after symptomatic presentation. As for the cases in this report, pamidronate was successful in reducing symptoms, and in the second case even led to regression of sclerotic changes on CT-imaging.Diabetes mellitus: pathophysiological changes and therap