Engineering Tissues And Organs In Vivo From Stem Cells
Funder
National Health and Medical Research Council
Funding Amount
$549,480.00
Summary
Tissue engineering is an exciting new area of medical research. We have developed a unique animal model of tissue engineering where new tissue spontaneously sprouts from the surface of a vascular loop enclosed inside a plastic chamber. The tissue thus created has its own blood supply. By adding cultured cells or altering the environment of the chamber we have been able to grow new specific tissues such as fat and muscle. This technology potentially allows the generation of spare body parts to re ....Tissue engineering is an exciting new area of medical research. We have developed a unique animal model of tissue engineering where new tissue spontaneously sprouts from the surface of a vascular loop enclosed inside a plastic chamber. The tissue thus created has its own blood supply. By adding cultured cells or altering the environment of the chamber we have been able to grow new specific tissues such as fat and muscle. This technology potentially allows the generation of spare body parts to replace lost or worn out organs and tissues. We have recently reproduced this model in the mouse to be able to screen a range of mouse and human stem cells. These cells have the ability to change (i.e. differentiate) into many different types of cell depending on how they are stimulated. In Part 1 of this project we will determine in the mouse chamber the growth characteristics and survival rates of these stem cells. A chamber encapsulating a flowing blood vessel will be implanted subcutaneously in each groin. In one chamber we will inject fluorescently labelled stem cells in a growth medium and in the other growth medium alone. Tissue will be analysed at 1, 2 and 4 weeks. In Part 2 we will inject a variety of Rosa26 labelled mouse stem cells obtained from several different tissues. Through the aid of naturally occurring growth and differentiation factors they will differentiate into one of several different tissues including fat, cartilage, bone, neural tissue, blood vessels, liver, etc, which will be identified by histology and cell culture. In one experiment we will genetically alter cells injected into the chamber so that they produce only skeletal muscle. In Part 3 we will grow new human tissues by injecting human stem cells into the same tissue engineering chambers in mice which will tolerate cells from other mammals (these are known as SCID mice). Success in novel method would be the precursor for the production of new human tissues to repair specific defects.Read moreRead less
In Vivo Tissue Engineering Of Adipose Tissue For Reconstructive Surgery
Funder
National Health and Medical Research Council
Funding Amount
$713,545.00
Summary
We are able to grow vascularised tissue in implanted plastic chambers to a predetermined size and shape in the rat and mouse (NHMRC Project Grant 01-03; #145782; CIA Morrison). The basis of this growth is blood vessel sprouting from the surface of the vessel bundle or loop, followed by synthesis of structural molecules and the migration of surrounding cells into the vascularised network to form a stable tissue. Unlike other in vivo models of tissue engineering, the tissue grows spontaneously and ....We are able to grow vascularised tissue in implanted plastic chambers to a predetermined size and shape in the rat and mouse (NHMRC Project Grant 01-03; #145782; CIA Morrison). The basis of this growth is blood vessel sprouting from the surface of the vessel bundle or loop, followed by synthesis of structural molecules and the migration of surrounding cells into the vascularised network to form a stable tissue. Unlike other in vivo models of tissue engineering, the tissue grows spontaneously and is densely vascularised, enabling continuous growth and surgically transfer to another part of the body, or to another animal. In this renewal application of the above NHMRC grant, we propose to direct these findings towards the development of vascularised fat tissue which would be ideal for reconstructive surgery as a stable, inert tissue filler. Our efforts to grow fat tissue in vivo to date have identified 4 major requirements: a fat precursor cell source; an instructive basement membrane matrix (which may include growth-differentiation factors); space into which the tissue can grow; a stable blood supply. We will focus here on optimising the precursor cell source and instructive matrix to generate vascularised fat tissue around the blood supply we can engender in our tissue engineering chamber. We have found Matrigel, a mouse tumor-derived matrix rich in basement membrane components, to be instructive for growing fat, and will also build on preliminary observations that either muscle or fat tissue can provide the appropriate precursor cells for this process. Finally we propose to adapt and upsize the vascularised fat tissue chamber to the pig, in a step towards human use, and assess its transplantability and longevity. The clinical application of our work is to produce breast reconstruction tissue and lipo filling for contour deformities resulting from trauma, congenital deformity, ageing and cancer surgery, particularly breast reconstruction.Read moreRead less
The Role Of Dysregulated VEGFs In Lymphatic And Non-lymphatic Vascular Malformations
Funder
National Health and Medical Research Council
Funding Amount
$389,486.00
Summary
Vascular malformations are abnormal growths of blood vessels that affect hundreds of children born in Australia every year. They range from small birthmarks to large destructive growths that cause chronic pain, bleeding and major deformity. This is the largest ever study to systematically look for the biological drivers that cause these growths so that drug treatments will ultimately be able to replace surgery as the first line treatment.
A Randomised Controlled Trial Comparing Intraoperative To Conventional Radiotherapy In Women With Early Beast Cancer.
Funder
National Health and Medical Research Council
Funding Amount
$874,046.00
Summary
With the advent of breast screening in Australia many women are diagnosed with small low risk cancers that can be treated with breast conserving therapy with good outcomes. Surgery and radiotherapy in this situation are used to minimise the risk of local recurrence. It is now being questioned whether we can tailor radiotherapy to suit individual patients rather than recommending the daily 6-7 weeks of standard external beam radiotherapy to all patients. This trial aims to answer this question as ....With the advent of breast screening in Australia many women are diagnosed with small low risk cancers that can be treated with breast conserving therapy with good outcomes. Surgery and radiotherapy in this situation are used to minimise the risk of local recurrence. It is now being questioned whether we can tailor radiotherapy to suit individual patients rather than recommending the daily 6-7 weeks of standard external beam radiotherapy to all patients. This trial aims to answer this question as a new device which can deliver radiotherapy intraoperatively in a single session has now been tested and proven safe to use in the breast. The main objective of this trial is to demonstrate that a single dose of radiotherapy delivered intraoperatively (IORT) gives an equivalent local control rate to standard external beam radiotherapy in women with early low risk breast cancer who are suitable for breast conserving therapy. Other objectives include comparing the two treatments with respect to; disease-free-overall survival, cosmetic outcome, patient satisfaction-preference, quality of life and cost benefit. If the study finds that IORT alone after breast conserving surgery is as effective in achieving local control as standard external beam radiotherapy, a major benefit to patients would be shorter treatment duration by avoiding the 6-7 weeks of standard radiotherapy. A reduction in the number of early breast cancer patients requiring access to standard radiotherapy would also benefit treatment centres and other cancer patients by reducing the waiting times for radiotherapy. Consumer groups have supported the concept from the beginning and there has been recent increase in level of support by originally unsupportive groups. Of great significance is this trial offers an opportunity to formally investigate the efficacy of delivering IORT in the safe confines of a clinical trial, before allowing it to become a standard treatment which is occurring in other countries.Read moreRead less
Improving Muscle Function After Injury: Novel Tissue Engineering Strategies For Exercise, Surgery And Sports Medicine
Funder
National Health and Medical Research Council
Funding Amount
$288,210.00
Summary
Muscles can be injured by excessive strains when playing sports, in road and workplace accidents, and during plastic and reconstructive surgery. Some surgeries require an unavoidable interruption to the muscle's normal blood supply (called 'ischaemia'). Subsequent return of the muscle's blood supply (reperfusion) is problematic in that a severe secondary muscle injury can ensue mediated by the influx of damaging free radicals when blood flow is restored. Tissue-engineering provides a novel thera ....Muscles can be injured by excessive strains when playing sports, in road and workplace accidents, and during plastic and reconstructive surgery. Some surgeries require an unavoidable interruption to the muscle's normal blood supply (called 'ischaemia'). Subsequent return of the muscle's blood supply (reperfusion) is problematic in that a severe secondary muscle injury can ensue mediated by the influx of damaging free radicals when blood flow is restored. Tissue-engineering provides a novel therapeutic approach to restore muscle structure and function to damaged muscles after injury or disease. Our recent research using controlled release of growth factors from biodegradable hydrogels has exciting application for muscle repairafter injury. We will utilize these cutting edge tissue engineering strategies to deliver to damaged muscles a hydrogel containing controlled delivery (slow release) microcapsules loaded with an anabolic agent (the beta-agonist, formoterol) and-or a growth factor (IL-15) designed to enhance functional muscle repair after three distinct but clinically relevant models of muscle injury: a) crush injury: A model for muscle injuries on the sports field, in the workplace, and those associated with road trauma; b) ischaemia-reperfusion injury: a model for muscle damage associated with surgical interventions, muscle transfers for functional restoration, and other injuries associated with plastic and reconstructive surgery; and c) contraction-induced injury: a model for strain injuries such as hamstring muscle tears that can occur on the sports field. After injury we will assess functional muscle repair using a comprehensive series of histological, biochemical, molecular, immunochistochemical, and physiological techniques. The research has broad application to exercise and clinical medicine; including sports, emergency and rehabilitation medicine, and plastic, reconstructive, and orthopaedic surgery.Read moreRead less
Randomised Controlled Trials Of Laparoscopic Techniques For Antireflux Surgery
Funder
National Health and Medical Research Council
Funding Amount
$1,031,381.00
Summary
Gastro-oesophageal reflux is common, with approximately 10% of Australians now using medication to control symptoms. Many Australians will need this medication for life, unless they undergo surgery. The cost of treating reflux is growing. Since 1992 the annual growth rate of the Pharmaceutical Benefits Scheme expenditure on reflux medication has been 13%, and the annual cost for the treatment of reflux now exceeds $1 billion. Not all patients with reflux are satisfied with medication, as some co ....Gastro-oesophageal reflux is common, with approximately 10% of Australians now using medication to control symptoms. Many Australians will need this medication for life, unless they undergo surgery. The cost of treating reflux is growing. Since 1992 the annual growth rate of the Pharmaceutical Benefits Scheme expenditure on reflux medication has been 13%, and the annual cost for the treatment of reflux now exceeds $1 billion. Not all patients with reflux are satisfied with medication, as some continue to experience symptoms. Surgery is the only treatment which will cure reflux. It has a clear role in the treatment of patients with ongoing symptoms, those who don t want to take tablets, and patients with a large hiatus hernia in whom symptoms occur due to the relocation of the stomach from the abdomen into the chest. Approximately 5,000 Australians per year undergo surgery for reflux. The standard operation achieves a good outcome in approximately 90%, although some patients are troubled by side effects. To reduce the risk of this, the original procedure has been modified. However, the evidence supporting modifications has until recently been limited. The best way to compare different operations is in randomised trials. The majority of the largest and best trials addressing this area have been undertaken in Adelaide. We have already entered 504 patients into 5 randomised trials, 4 conducted entirely in Adelaide, and one across multiple sites with the cooperation of 15 Australasian surgeons. These trials have provided a more reliable evidence base for surgeons undertaking surgery for reflux. However, long term follow-up is required to ensure that conclusions drawn are valid at late follow-up. In addition we are establishing 2 new randomised trials, which will determine how best to perform surgery for reflux, and how best to repair a large hiatus hernia. These studies will be undertaken in collaboration with more than 25 other surgeons throughout Australia.Read moreRead less
Pancreatic Cancer is the fourth leading cause of cancer death in men and women in Western societies. Nothing, apart from surgery in a small proportion of individuals gives any hope. The identification of novel treatment strategies in the modern era necessitates a rational scientific approach, where an understanding of the molecular mechanisms involved in the evolution of cancer underpins the development of such strategies in an efficient manner. Retinoids are derivatives of Vitamin A, and have b ....Pancreatic Cancer is the fourth leading cause of cancer death in men and women in Western societies. Nothing, apart from surgery in a small proportion of individuals gives any hope. The identification of novel treatment strategies in the modern era necessitates a rational scientific approach, where an understanding of the molecular mechanisms involved in the evolution of cancer underpins the development of such strategies in an efficient manner. Retinoids are derivatives of Vitamin A, and have been used extremely successfully in the treatment of some leukaemias. Unfortunately, retinoids have not worked as well in other cancers. We have identified an important role for abnormal retinoid function in the evolution of pancreatic cancer, which may be responsible for the lack of effective response to retinoid treatment. This project focuses on identifying if these abnormalities in retinoid function can be reversed with adding specific pharmaceuticals so that retinoid based therapies will be effective in pancreatic cancer.Read moreRead less
Delayed Phase Of Remote Ischemic Preconditioning: Clinical Application And The Role Of Kallikrein-kinin Pathway.
Funder
National Health and Medical Research Council
Funding Amount
$159,197.00
Summary
Brief episodes of interruption of blood flow to the arm or leg provide strong protection against prolonged interruption of blood flow to a target organ (e.g., heart or lung). This is known as remote ischemic preconditioning (RIPC). The strongest protection occurs 24 hours after blood flow interruption to the limb and may be mediated by a humoral cascade known as kallikrein-kinin. RIPC may provide protection against heart attack and stroke.
Perioperative Beta-blockade To Prevent Cardiac Morbidity In High-risk Patients Undergoing Surgery (The POISE Study)
Funder
National Health and Medical Research Council
Funding Amount
$189,625.00
Summary
Non-cardiac surgery is associated with significant risk of complications and death, particularly in elderly patients who are known to have heart disease, or who have risk factors for it (ie smoking, high blood pressure). About 11% of the Australian population are currently taking medications for heart disease or high blood pressure and about 80% have at least one risk factor for heart disease. As more than 2 million Australians have general anaesthesia for non-cardiac surgery every year, a subst ....Non-cardiac surgery is associated with significant risk of complications and death, particularly in elderly patients who are known to have heart disease, or who have risk factors for it (ie smoking, high blood pressure). About 11% of the Australian population are currently taking medications for heart disease or high blood pressure and about 80% have at least one risk factor for heart disease. As more than 2 million Australians have general anaesthesia for non-cardiac surgery every year, a substantial group of patients are therefore at risk of an adverse outcome following surgery. Despite the magnitude of this problem, however, few studies have established treatments to decrease the risk of complications and death following surgery. Beta-blockers are a group of drugs which have been used for decades in the treatment of heart disease and high blood pressure. Beta-blockers are known to improve the way the heart copes with the stress of surgery. They decrease the heart rate, make the heart more efficient at using energy and reduce the likelihood of imbalance between oxygen supply and demand. Some previous studies showed that beta-blockers may reduce the risk of heart attack and death for up to 2 years after surgery. However, other studies have shown no effect of beta-blockers on outcome. These previous studies have involved small numbers of patients who may not represent the broader population having surgery. We therefore propose to undertake a large trial to definitively answer the question about whether beta-blockers improve the outcome after non-cardiac surgery in patients with, or at risk of, heart disease. Even if the effect of beta-blockers is relatively modest, because such large numbers of patients with heart disease have surgery, the overall effect on the rate of complications and death in the population could be very significant. The results of this study could have major implications for the success of, and cost of, surgery worldwide.Read moreRead less
QUANTITATIVE ASSESSMENT OF LOOSENING IN HIP ARTHROPLASTIES USING MECHANICAL VIBRATION DIAGNOSTICS
Funder
National Health and Medical Research Council
Funding Amount
$185,665.00
Summary
Recent advances and improvements made to the mechanical design of artificial joints have led to greater strength, fatigue life and wear resistance. However, this extension to the working life of joint replacements has led to patients becoming increasingly vulnerable to the problem of joint loosening. There are over 500 000 hip joint replacements performed every year, on a worldwide basis. Of these 7 to 13% will require revision surgery because of loosening at some stage of their working life. Th ....Recent advances and improvements made to the mechanical design of artificial joints have led to greater strength, fatigue life and wear resistance. However, this extension to the working life of joint replacements has led to patients becoming increasingly vulnerable to the problem of joint loosening. There are over 500 000 hip joint replacements performed every year, on a worldwide basis. Of these 7 to 13% will require revision surgery because of loosening at some stage of their working life. This is becoming a major concern to health services around the world since revision surgery is associated with a higher risk to the patient and costs are far greater than for the primary operation. Current diagnostic techniques using radiographic imaging are both invasive and lack diagnostic accuracy. The ability to detect joint loosening and to discriminate between the various causes of joint loosening following arthroplasty is of great importance to the success of subsequent care plans. This study will be the first in the world to assess the validity of a new diagnostic test that uses low energy mechanical vibration to quantify the degree of loosening in both components of the implanted hip joint. Once the technique has been proven it could readily be extended to evaluate the degree of fixation of other implanted prostheses used to replace the knee, ankle or joints of the upper limbs.Read moreRead less