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The biggest cardiovascular center in The Netherlands

I worked temporarily at The Catharina hospital in Eindhoven last month . In the first day I had problems finding the main entrance . I parked the bicycle quickly near an entrance with a large building site . After I finished working in that day I asked at the information desk which one is the main entrance . I found out that I entered through it . While unlocking the bicycle , I looked up and read on a panel that I was standing not in front of an ordinary building site , but in front of the one for the biggest cardiovascular center in The Netherlands . I could not resist the temptation to write a post about it .

The Catharina hospital is a modern clinical training hospital , located in Eindhoven , The Netherlands . Although there are many options to find treatment at any hour , in any part of the city , people come at this hospital . I did not encounter any person living in this city that would not check in here , at some point . I found out on their website that it holds the quality mark in healthcare , awarded by The Netherlands Institute for Accreditation in Healthcare ( The NIAZ ) in 2000 . I found out on their LinkedIn group that the hospital has awarded the certificate of " top employers cure and care 2015" .

Figure 1 . The Catherina hospital , in Eindhoven , The Netherlands

The cardiovascular center is the biggest one in The Netherlands . The center already provides diagnosis and treatment for coronary artery disease and stenosis , heart failure , ablation , arrhythmia , valvulopathy , aortic and mitral valve , heart and valve surgery ; high quality research in blood testing , cardiogenetics , cardio - memo , computerised tomography ( CT ) scanning , echocardiogram , fractional flow reserve ( FFR ) measurement , and cardiac catheterisation .

The location of the cardiovascular center is , at the moment , in the main building of the hospital . When the new building section is ready , the centre will move in the new location , giving space to additional rooms for patients in the main hospital building .

Figure 2 . The biggest heart centre from The Netherlands , at The Catharina hospital in Eindhoven

The program Measurable better connects top clinicians and scientists from fourteen cardiovascular centers , and five intervention centers . The cardiovascular centers that joined the program are : The Catharina hospital , The academic medical center Amsterdam , The Amphia hospital , The Erasmus MC , The Hague hospital , Isala , Maastricht UMC + , The medical center Leeuwarden , The medical spectrum Twente , The " Our dear lady " hospital , Radboudumc , The saint Anthonius hospital , The universitary medical center Groningen , and The universitary medical center Utrecht . The five intervention centers that joined the program are : The " Elizabeth two cities " hospital , The Jeroen Bosch hospital , The Maasstad hospital , The medical center Alkmaar , and The Tergooi .

The Catharina hospital provides complex top clinical assistance in the diagnosis and the treatment of cardiac rhythm , in interventional cardiology , and in the cardiothoracic surgery . It is one of the centers that aims to have high quality patient care , with improved transparency . It was an honour working in the hospital .

The microRNA in tissue regeneration

I found a very interesting article that provides a concise literature review with 80 papers about original research in translational medicine .

The polymeric molecules that are the subject of discussion today are the microRNAs ( miRNA ). They are perfect complements to the target messengerRNA ( mRNA ) in plant cells , but they slightly mismatch in base pairing inside animal cells . The gene regulation using the complex micro RNA - m RNA triggers a wide variety of cellular mechanisms .

The cellular mechanisms that achieve organ regeneration , in a spatiotemporally controlled manner , are the differentiation , the dedifferentiation , the transdifferentiation , and the cellular proliferation . They alter the cellular plasticity .

The researchers learn from the invertebrates , the lower vertebrates , and the mammals how to activate the pluripotent stem cells in order to regrow parts or the entire organism . The trigger for the chain of events in the regeneration process is either the under - or the over - expression for the specific microRNA . The article provides a list for the microRNAs that regulate the human mesenchymal , and the human pluripotent ( the human embryonic , the human induced pluripotent ) stem cells .

The modulation of the regeneration process using microRNAs may be done by varying the modulators , the delivery method , or the cellular strategy ( figure 1 ) . The target cells are either the implanted or the endogeneous cells . The scientist may apply a modulation strategy on the endogenous ( stem ) cells , on the implanted cells prior to implantation , or on both the endogenous cells and the implanted cells . The modulators are either the cells themselves , the synthetic oligonucleotides , or the level of expression . The paper presents four delivery methods for the microRNAs : through direct injection , with viruses , with synthetic nanoparticles , and with cells as delivery vehicles .

Figure 1 . The technique variations for the micro - RNA signaling in the process of tissue regeneration .
Copyright ( 2014 ) AlphaMed Press

The heart has a limited potential for endogenous regeneration . The neonatal heart has a different response to myocardial infarction than the adult heart . The underexpressed microRNAs that trigger the proliferation of the cardiomyocytes are the miR - 15 family , the miR - 17 - 92 cluster , the miR - 199a and the miR - 590 families . They may help in the differentiation for the stem cells , for the cellular lineage commitment , and in the direct reprogramming process of the fibroblasts to generate cardiomyocytes . They are critical components in the signalling network for the adult cellular proliferation .

The microRNAs have a complex behaviour that is still not yet fully understood . The modulation strategy varies with the target organ that requires regeneration , and the research application .

References :

Frith J . E . , Porrello E . R . , Cooper - White J . J . ( 2014 )" Concise review : new frontiers in MicroRNA - based tissue regeneration " , Stem Cells Translational Medicine , 3 ( 8 ) , 969 - 976 .

The production of the spider silk

The structure of the silk fibre has two components , a crystalline one incorporated in the semi - amorphous region . The crystalline section contains poly – ( Gly – Ala ) , and poly – Ala nano – domains , filling in 50 % of the volume . The weak Hydrogen bonds have the functionality to link the nano – domains , in 10 – 15 % of the volume . The overall fibre is a natural block copolymer , with the elastic capacity from 500 % to 1000 % , and with the tensile strength in the GPa magnitude .

The Araneidae , a garden spider , weaves the two - dimensional web to capture insects . The web silk for this spider does not break when the insect attaches . The retraction time of the extended web spiral is small , so that the silk does not attach to unwanted elements . The silk coated naturally with a hydroscopic glue , has increased elasticity . The researchers analyse the natural phenomenon , both in the absence , and in the presence of fluid . Figure 1 summarises two experiments , a and b , conducted with the same setup , in the laboratory . The stretching curve is red , and the retraction curve is blue .

Figure 1 . The force spectra of the silk web molecules for The Araneidae ( the orb – weaving spider ) .
Copyright ( 2003 ) Nature Publishing Group

The natural method to produce silk has yet many unknowns for the researchers . The spider silk produced naturally is in limited volume . A method to produce hand - made silk , similar to the spider silk , with lower tensile strength , is from the transgenic silk worms, and from the milk of the transgenic goats .

A suitable match between the material properties of biomaterials and the ones of the cardiac tissue may be improved . A scaffold may be electrospun with the silk solution , with or without the addition of extra cellular matrix solution .

References :

Becker N . , Oroudjev E . , Mutz S . , Cleveland J . P . , Hansma P . K . , Hayashi C . Y . , Makarov D . E . , Hansma H . G . ( 2003 ) “ Molecular nanosprings in spider capture – silk threads ” , Nature Materials , 2 , 278 - 283 .

The robotic surgery procedure for the mitral valve

The leaflet of the mitral valve may prolapse , and lead to an increased fibrous ring . The surgeon may correct each part of the valve in a procedure that is minimally invasive . The robotic arm aids the surgeon to operate more precisely on the region of interest , from the console . The benefits for the patient from a procedure that does not split the breastbone are : less pain after surgery , short hospitalisation time , low risk of infection , quick recovery , and , of course , less marks on the body .