Probing the mechanism for hydrogel-based stasis induction in human pluripotent stem cells: is the chemical functionality of the hydrogel important?

It is well-known that pluripotent human embryonic stem cells (hPSC) can differentiate into any cell type. Recently, we reported that hPSC colonies enter stasis when immersed in an extremely soft hydrogel comprising hydroxyl-functional block copolymer worms (I. Canton, N. J. Warren, A. Chahal, K. Amps, A. Wood, R. Weightman, E. Wang, H. Moore and S. P. Armes, ACS Centr. Sci., 2016, 2, 65-74). The gel modulus and chemical structure of this synthetic hydrogel are similar to that of natural mucins, which are implicated in the mechanism of diapause for mammalian embryos. Does stasis induction occur merely because of the very soft nature of such hydrogels or does chemical functionality also play a role? Herein, we address this key question by designing a new hydrogel of comparable softness in which the PGMA stabilizer chains are replaced with non-hydroxylated poly(ethylene glycol) [PEG]. Immunolabeling studies confirm that hPSC colonies immersed in such PEG-based hydrogels do not enter stasis but instead proliferate (and differentiate if no adhesion substrate is present). However, pluripotency is retained if an appropriate adhesion substrate is provided. Thus, the chemical functionality of the hydrogel clearly plays a decisive role in the stasis induction mechanism.

Peri-operative management of the surgical patient with diabetes 2015: Association of Anaesthetists of Great Britain and Ireland.

Diabetes affects 10-15% of the surgical population and patients with diabetes undergoing surgery have greater complication rates, mortality rates and length of hospital stay. Modern management of the surgical patient with diabetes focuses on: thorough pre-operative assessment and optimisation of their diabetes (as defined by a HbA1c < 69 mmol.mol(-1) ); deciding if the patient can be managed by simple manipulation of pre-existing treatment during a short starvation period (maximum of one missed meal) rather than use of a variable-rate intravenous insulin infusion; and safe use of the latter when it is the only option, for example in emergency patients, patients expected not to return to a normal diet immediately postoperatively, and patients with poorly controlled diabetes. In addition, it is imperative that communication amongst healthcare professionals and between them and the patient is accurate and well informed at all times. Most patients with diabetes have many years of experience of managing their own care. The purpose of this guideline is to provide detailed guidance on the peri-operative management of the surgical patient with diabetes that is specific to anaesthetists and to ensure that all current national guidance is concordant.

Integrated approaches to academic anaesthesia - the Cambridge experience.

There is mounting concern about the pressures experienced by University Departments of Anaesthesia, which, if lost, could threaten undergraduate peri-operative medicine teaching, development of critical appraisal skills among anaesthetists, and the future of coherent research programs. We have addressed these problems by establishing a foundation course in scientific methods and research techniques (the Cambridge SMART Course), complemented by competitive, fully funded, 12-month academic trainee attachments. Research conducted during academic attachments has been published and used to underpin substantive grant applications allowing work towards higher degrees. Following the attachment, a flexible scheme ensures safe reintroduction to clinical training. Research at consultant level is facilitated by encouraging applications for Clinician Scientist Fellowships, and by ensuring that the University Department champions, legitimises and validates the allocation of research time within the new consultant contract. We believe that these are important steps in safeguarding research and teaching in anaesthesia, critical care and peri-operative medicine.

A questionnaire survey of resuscitation equipment carried by general practitioners and their initial management of ventricular fibrillation.

BACKGROUND: The early defibrillation of patients having a cardiac arrest and who are in ventricular fibrillation has been shown to increase survival and is recommended by the European Resuscitation Council (ERC) and the American Heart Association. General practitioners (GPs) may expect to encounter a cardiac arrest in 5% of patients they attend who have a suspected acute myocardial infarction. AIM: To establish whether GPs on call were equipped to treat a patient in ventricular fibrillation, and to investigate their knowledge of the early stages of the current ERC guidelines for this cardiac rhythm. METHOD: A postal questionnaire was sent to all the 175 GPs who regularly admit patients to the West Suffolk Hospital. It asked for details of equipment and drugs carried when on call, recognition of a cardiac rhythm strip of ventricular fibrillation, and treatment to be given for this rhythm. RESULTS: A total of 105 replies were returned (representing a 60% response rate). The distribution of practice size and location reflected primary health care in this area. Fourteen GPs (13%) had attended an advanced cardiac life-support course at some time, and 44 (41.9%) had read the current ERC guidelines. The majority of GPs (60%) carried advanced airway management equipment to allow endotracheal intubation, but only 37 (35%) would have been able to administer additional oxygen. Again, most (82%) would have been able to establish intravenous access, but only 39% carried 2 mg or more of adrenaline, the only recommended drug in the initial stages of resuscitation from ventricular fibrillation. A defibrillator was carried by 37 GPs (35%) when on call, but out of these only 14 had an integral monitor screen and 3 were semi-automatic defibrillators. Ninety-five GPs (91%) successfully identified ventricular fibrillation, but only 32 (31%) were able to state correctly the initial recommended treatment, and only 17 (16%) were able to quote the first two stages of the ERC guidelines of treatment of ventricular fibrillation. However, 78 GPs (74%) would have provided treatment compatible with the guidelines by giving the patient a pre-cordial thump and two subsequent defibrillatory shocks, albeit perhaps at an incorrect energy level and only if a defibrillator was available. CONCLUSIONS: This study shows that the equipment carried by the majority of GPs in this area is inadequate to deal successfully with the victims of cardiac arrest, and that significant reliance is placed on the resources of the ambulance service. It would also appear that most GPs are not fully conversant with the current ERC guidelines. The ability of GPs to manage cardiac arrests could be enhanced by their attending courses to update their resuscitation skills, one example being the advanced life-support courses endorsed by the United Kingdom Resuscitation Council, and that the Royal College of General Practitioners could stimulate interest in this area by extending their requirement for candidates for the membership examination to include written documentation demonstrating proficiency at advanced life support, in addition to the current requirement for basic life support only.