Sanya Specific

Question 1

Summarise your stroke project

Answer 1

Retrospective audit of estimated weight with later weight measurements of patients admitted for stroke thrombolysis. Differences were analysed by two tailed t-test and were statistically significant. Secondary analysis showed that this would cause dosing inaccuracies of over 5mg in 25% of patients and over 9mg in 10% of patients.

900 micrograms/kg, so for a 75kg patient is 67.5mg. 5 mg is likely to be clinically significant. However, it would not be ethical to follow up the clinical effects of inaccurate dosing as there is not clinical equipoise on the matter (NINDS trial). It was therefore reasonable to conclude that there is a need for more accurate weight measurements.

Question 2

What was the NINDS trial?

Answer 2

Prior pilot studies suggested that tPA was beneficial when treatment was begun within 3 hours of stroke onset, but the 1995 National Institute of Neurological Disorders and Stroke rt-PA Stroke Study (NINDS) was the first to establish efficacy of thrombolysis within a 3-hour time frame for ischemic stroke. The NINDS trial demonstrated improvements in functional outcomes at 3 months if thrombolysis was administered within 3 hours of symptom onset, with the greatest benefit seen within 90 minutes. Despite a tenfold increase in symptomatic intracranial hemorrhage (ICH), there was no significant difference in mortality among those receiving tPA. These results were confirmed in ATLANTIS A

The subsequent ECASS III trial (2008), demonstrated a benefit of IV alteplase beyond the conventional 3-hour window, effectively extending the window for alteplase to 4.5 hours. A 2014 meta-analysis found a benefit for tPA therapy up to 4.5 hours, though there was a higher rate of a low Modified Rankin score with tPA administration <3 hours (NNT 9; 95% CI 6-18) than between 3-4.5 hours (NNT 20; 95% CI 11-97). There was no benefit of tPA administration later than 4.5 hours

Question 3

How is dosing established in clinical trials?

Answer 3

By dose ranging study

Dose-ranging is usually a phase I or early phase II clinical trial. Typically a dose ranging study will include a placebo group of subjects, and a few groups that receive different doses of the test drug

Question 4

Can you give an example of murine studies that do not translate into clinical success?

Answer 4

ALS

Question 5

Why do so many clinical trials fail?

Answer 5

Boston consulting group did some research into failure factors:

Success rate not dependent on company

Researchers from Pfizer recently published a powerful analysis showing that two-thirds of the company’s Phase I assets that were progressed could have been predicted to be likely failures on the basis of available data

Some believe it is more as a result of many compounds being tested with no specificity of what is put forward to clinical trial

Other papers argue that it is due to a very rigorous research process - factors including meeting deadlines, ethics submissions, patient recruitment, funding

Question 6

Tell me about the cellular process of ageing

Answer 6

The Hallmarks of Aging - Cell

• Nine tentative hallmarks of ageing that seem to commonly be affected in different organisms:

1. Genomic instability
2. Telomere attrition
3. Epigenetic alterations
4. Loss of proteostasis
5. Deregulated nutrient sensing
6. Mitochondrial dysfunction
7. Cellular senescence
8. Stem cell exhaustion
9. Altered intercellular communication

Question 7

What is the difference between cancer and regeneration?

Answer 7

Cancerous growth does show some similarities:

• Ability to differentiate
• Rapid cell division
• Metabolic activity

However it is a deregulated process and also shows some similarities with ageing

• accumulation of cellular damage
• genomic instability
• loss of proteostasis
• altered intercellular communication

Question 8

Tell me about ELISA

Answer 8

ELISA is a technique that uses antibodies to detect proteins as part of an assay

Advantages:

• highly sensitive
• can be quantitative
• relatively quick
• available for many substances

Disadvantages
- Antibody may bind to other substances in the well and so there is a need for positive and negative controls to measure against

Question 9

Tell me about your research to date

Answer 9

• Dry laboratory

I sought out this research project to complete in my spare time. We investigated whether PSI improved surgical accuracy in total hip arthroplasty. I was involved in conducting the pilot study, which was also proof of concept, and the data collection. I wrote an abstract for the work and submitted this to the RSM. I was invited to present my work and won first prize. It was a really rewarding project and a brilliant introduction into research. From this work, I have been invited to contribute to the peer review process for the International Journal of Medical Robotics and Surgery. (1 systematic review and 1 clinical project on computer-assisted hip surgery, 1 clinical project on total knee replacement with computer assisted knee surgery)

• Wet laboratory

I investigated the pro-inflammatory effects of methaemoglobin on A549 cells. This involved quickly grasping wet laboratory techniques such as cell culture, ELISA and permability studies. I was also involved in the grant application process. Although the significant results had previously been published, I fostered good relationships with members of the research team and was asked to write a review of the literature to date. I am in the process of writing this now.

• Laboratory review

The aim of the review is to evaluate the role of cell free haemoglobin as a common disease pathway. It is implicated in many diseases such as CVD, sickle cell, malaria and ARDS. Broadly, cell free haemoglobin has been shown to increase bacterial virulence, upregulate pro-inflammatory cytokines and cause endothelial dysfunction and the review evaluates the evidence behind this.

• AIM of project, ROLE, RESULT

Question 10

What is the difference between an audit and a research project

Answer 10

An audit evaluates adherence to a protocol

Question 11

Can you think of a clinical situation that has lead to an idea for a research project?

Answer 11

Use of NOACs perioperatively (aspirin has been shown to be safe perioperatively in rct of CVD patients in non cardiac surgery)

PrP - As of 2016 results of basic science and preclinical trials have not yet been confirmed in large-scale randomized controlled trials. A 2009 systematic review of the scientific literature found there were few randomized controlled trials that adequately evaluated the safety and efficacy of PRP treatments and concluded that PRP was “a promising, but not proven, treatment option for joint, tendon, ligament, and muscle injuries”

Total knee arthroscopy - Moseley trial (no difference between sham and real) and METEOR (meniscal tear and physio vs menisectomy in pts with osteoarthritis)

Question 12

Who funds medical research?

Answer 12

• MRC
• UK Regenerative medicine platform (smartstep) - 1.1mil grant
• Arthritis research UK

Question 13

Which research projects would you be interested in?

Answer 13

Innovabone - using materials to form scaffolds and encourage bone regeneration

Interested in translational research in the context of cell regeneration in orthopaedics

Question 14

Why ageing?

Answer 14

I am interested in the ageing process from a scientific point of view, but also as a clinician with an interest in orthopaedics.

Recently some interesting theories have been discussed within ageing, for example the idea that this might be an energy saving process that provided an evolutionary benefit. That ageing may be a pathological process and that it is due to fundamental cellular processes with different effects within the body.

Musculoskeletal system combines regenerative tissue (muscle) and bone, which is one of the first organs to degenerate.

Prosthetics have previously targeted orthopaedic problems in the ageing population such as osteoarthritis, but are limited in that their lifespan is being overtaken by patient lifespan.

Regenerative medicine seems a natural next step in orthopaedic research. In fact, denosumab may be the first step in replicating osteoprotegerin, a molecule that declines with age.

In medicine we are held between promoting longevity and improving quality of life. I believe that the question of ageing may provide the best solution for both aims

Question 15

Where do you see yourself in 10 years time

Answer 15

I will be 34 years old.

As I plan to undertake a PhD, I will be 3 years into orthopaedic training, preferably as an academic clinical fellow.

By this point, I hope to have discovered an area of research that I can continue to pursue for the rest of my career. I hope to have experienced many academic intitutions and have an idea of which I would like to stay in as I begin to put together my own research team.

As a clinician, I hope to have developed key surgical skills and be able to perform small surgeries unsupervised.

I would also like to have a regular teaching committment where I can provide mentorship and make changes to a university curriculum.

Question 16

Give an example of owning up to a mistake

Answer 16

Illegible handwriting

Patient safety first

Importance of owning up - facing consequences and using as a learning tool for the future

Result: in my mind now to ensure my writing

Question 17

Talk about a paper you read recently

Answer 17

This is an open label randomised control trial, which aimed to assess the efficacy of fusion surgery in lumbar spinal stenosis. The trial involved 247 patients from 50-80years who had lumbar spinal stenosis and who were stratified for disease severity and randomised to receive either decompression surgery or decompression and fusion surgery. The primary outcome was a patient reported outcome, the Oswestry Disability index, with secondary outcomes of 6 minute walk test, and health economic factors including hospital stay, operating time, blood loss, surgical costs and additional spinal surgery rates. The trial did not find any significant difference in patient reported or functional outcomes, nor in rates of additional spinal surgery. However, mean hospital stay, operating time, blood loss and surgical costs were higher in the group receiving fusion surgery. The paper concluded that in patients with lumbar spinal stenosis, fusion surgery did not result in better clinical outcomes at 2 years and 5 years than decompression surgery alone.
The paper has many strengths – it was a randomised control trial, stratified for disease severity. Patient reported and functional outcomes were measured as well as health-economic analysis which helps to relate the paper to a clinical context. Long term follow up.

There are a few weaknesses to the study. The trial was open label, so susceptible to expectation bias and observer bias. The intervention is not compared to gold standard, reported by cochrane as a laminectomy.

Question 18

What are the advantages and disadvantages of academic medicine

Answer 18

ADVANTAGES

• integrate scientific concepts and statistics to innovate clinical changes
• more diverse communication - multidisciplinary team is wider, teaching
• more practised skill set to evaluate clinical evidence and guidelines

DISADVANTAGES

• less time for clinical competencies
• less pay
• frustration of a project you believe in not reaching fruition

Question 19

Greatest medical advancement in the last 10 years

Answer 19

Conversion of somatic cells into pluripotent stem cells

The most noted problem is the use of retroviral and lentiviral vectors to introduce the four transcription factor genes into somatic cells for cell reprogramming. These viral vectors preferentially integrate into active genes and therefore have the potential to activate flanking cellular genes and transform the transplanted cells. In addition, most of the four introduced transcription factors possess oncogenic potentials, and persistent expression of any of them may provide cell growth advantage and increase the chance for cell transformation. Although expression of these four genes for the most part is silent in established iPS cell lines, residual expression or reactivation of their expression in transplanted iPS cells can induce tumors in mice. Thus, although iPS cells derived from this route may be suitable for the study of disease mechanisms or for drug screening and validation, they definitely are not suitable for cell replacement therapy.

Many alternative gene delivery strategies — including the use of episomal vectors, nonintegrating viral vectors, transient DNA transfection, transposons, and protein transduction — can overcome this problem. A general principle common to all these strategies is the transient expression of the four transcription factors at sufficient levels to trigger the initiation of the cell reprogramming event without permanent integration of the four genes into the host genome. Although these strategies work for the most part, the efficiency of generating iPS cell lines is significantly reduced compared with the approach of retroviral and lentiviral vectors.

Use of small molecules to activate the pluripotency program in somatic cells represents perhaps the safest approach to create reprogramming factor-free iPS cells. Several small molecules, when used singly, could substitute for some of the reprogramming factors. However, so far it is not possible to use only small molecules to reprogram somatic cells. High throughput screening of small molecules for cell reprogramming is ongoing in many laboratories, and the ultimate goal would be to establish iPS cells free of any exogenously introduced DNA fragments.

Yet another problem with iPS cells in the study of disease mechanism is that defining a disease-related phenotype is frequently hindered by the intrinsic variability in differentiation potentials observed among different iPS cell lines. This variability makes it less certain that any observed phenotype in cells derived from a single iPS cell line is caused by the defective gene function. Therefore, to ensure that the exhibited phenotypes are not unique to a specific iPS cell line or a particular patient, it is important to evaluate several iPS cell lines generated from the same patient as well as those generated from different patients with the same disease. Alternatively, restoration of the missing gene function in mutant iPS cells provides an ideal isogenic control for any observed phenotype.

For practical application of this technology in clinics, we need to resolve issues involving the use of viral vectors for iPS cell establishment, the safe strategy to genetically modify iPS cells, differentiation of iPS cells into relevant cell types in vitro for transplantation, and removal of contaminating stem or progenitor cells before transplantation. Study of abnormal phenotypes exhibited in iPS-derived cell lineages, such as in the cases of SMA and FD, opens up the possibility of using this technology to model human diseases in vitro. However, to facilitate the study of underlying disease mechanisms, we need to reveal a full spectrum of disease phenotypes in the affected cell type derived from iPS cells, especially those involved in functionality of the differentiated cells. The iPS cell technology may also contribute to drug validation and screening.

In the case of SMA, administration of valproic acid and tobramycin showed an improvement in the biochemical characteristics of iPS cells, but it remains unclear whether such treatment also improves the phenotypic deficit such as the neuron outgrowth defect. Treatment of FD iPS cells with kinetin, a plant hormone, throughout neuronal differentiation resulted in a significant increase in the percentage of neurons. These studies illustrate the promise of this technology in drug validation and screening. Because drug screening in most cases requires the exhibition of a phenotype in the cell target, developing efficient strategies to generate such cell targets from iPS cells for high throughput assays remains a major challenge. Despite these challenges, the potential of iPS cells remains enormous. Resolution of these challenges will have significant implications in the understanding of human diseases and will have major effects on the therapeutic treatment of these diseases.