Potential Honours projects for Biological Anthropology for 2010

• Secular trends in anatomical character of Australian people
• Comparative anatomy of marsupials
• Comparative anatomy of primates
• Physical growth of Australian children and youth under varying-socio-economic conditions.
• Building faces from skulls for forensic identification
• Skeletal anatomy for forensic identification
• Human faces and evolution
  

Habitual physical activity and body mass

Supervisors; Prof Stanley J Ulijaszek
stanley.ulijaszek@anthro.ox.ac.uk,

Prof Maciej Henneberg
maciej.henneberg@adelaide.edu.au

Obesity is one of the major health problems of the 21st century. Increased fatness is a result of the imbalance between nutritional energy intake and energy expenditure. Human energy expenditure has two components: basal metabolic rate and field metabolic rate. The first is measured as the energy required to maintain functions of the body when the boy is at rest. The second includes energy consumed during all activities. It is believed that with the modern lifestyle there was a reduction in habitual physical activity of indviduals. A major component of this reduction is use of transport that replaces individual locomotion. This project aims to explore a relationship between fatness and habitual physical activity of individuals. Volunteers will be measured to obtain anthropometric evaluation of their body size and fatness and then interviewed to gain information on their daily physical activities. A hypothesis linking increased fatness to reduction in daily energy expenditure through habitual physical activities will be tested by means of statistical analyses of the data collected.

This project is a part of the research programme of the Unit for
Biocultural Variation and Obesity http://www.oxfordobesity.org

Body frame size, dietary intake and fatness

The current "obesity epidemic" is a major public health problem. Although it is obvious that the major cause is increased dietary intake and reduction in physical activity, there are differences in the amount of weight gain by various individuals. It has been recently suggested that differences in individual fatness are correlated to the size of the lean trunk, as measured by the bony frame of the body (width and depth of the chest, width of the bony pelvis). The hypothesis is that lager lean trunk size is related to larger gastrointestinal tract which in turn requires larger food intake to obtain satiety mediated through ghrelin secretion following expansion of the antral part of the stomach. Were this true, the individuals with larger body frame, as especially susceptible to the development of obesity, can be prevented from developing excessive fatness through early provision of counselling as to weight control. This project will test this hypothesis by obtaining anthropometric data on body frame size and fatness of volunteers who will also provide information about their food intake. The hypothesis will be tested by means of a statistical analysis of the relationship between body frame, food intake and fatness.

This project is a part of the research programme of the Unit for Biocultural Variation and Obesity http://www.oxfordobesity.org

Relationship of the size and shape of the external ear to craniometric characteristics

Supervisor: Maciej Henneberg, co-supervisor Karen Anderson

Anthropometric techniques to be used on  cadavers and living people to produce guidelines for the reconstruction of the external ear from the skull. General approach similar to that described in:

Henneberg M,Stephan C, Simpson E ,2003, Human face in biological anthropology:craniometry, evolution and forensic identification. In: M. Katsikitis (ed.) The Human Face:Measurement and Meaning, Kluwer Academic Publishers, Dodrecht, Netherlands. pp. 29-48

Simpson EK, Henneberg M, 2002 Variation in soft tissue thicknesses on the human face and their relation to craniofacial dimensions, Am. J. Phys. Anthropol. 118:121-133

Shape of the human nose in full face view - assessment of variability in young Australian males

Supervisor: Maciej Henneberg, co-supervisor Karen Anderson

A descriptive study of a sample of young Australian males to ascertain variation in nose shapes to assist forensic identification from CCTV images. A sample of some 200 volunteers would have to be recruited, photographs of their noses taken and analysed statistically. General approach described in:

Henneberg M,Stephan C, Simpson E ,2003, Human face in biological anthropology:craniometry, evolution and forensic identification. In: M. Katsikitis (ed.) The Human Face:Measurement and Meaning, Kluwer Academic Publishers, Dodrecht, Netherlands. pp. 29-48details of the study of nose profiles  described in unpublished Honours Thesis of Erin Forbes, obtainable from M. Henneberg for perusal.

Laterality - how well determined is it in left- and right- handers ?

Supervisor; Maciej Henneberg

Results of re-training of left- and right handers to write with the non-dominant hand need to be compared. The hypothesis that most people can write with the non-dominant hand well has been partly proven, but it requires further study, especially with regard to left- handers. A sample of 10 left-handers and 10 right-handers would have to be obtained and subjected to several weeks' training in writing for about 30 minutes a day. Basic research scheme described in:

Chapman JA, Henneberg M, 1999 Switching handedness of adults: Results of a 10-week training in writing with the non-dominant hand,
Pespectives in Human Biology 4(1):211-217

Walker L, Henneberg M, 2007 Writing with the non-dominant hand: cross- handedness trainability in adult individuals, Laterality 12(2):121-130

Body frame and adiposity in children developing in various conditions

Supervisor: Maciej Henneberg

It has recently been found that the lean size of the trunk (also called "body frame") is related to increased thickness of subcutaneous fat layer (Henneberg and Ulijaszek 2009).  The question remains how early in life this relationship can be observed and how is it related to conditions in which children develop. Data on body size and adiposity have been collected among over 4000 children living in very poor and very good conditions in Africa. This database can be used to study the problem of relationship between body frame size and obesity through statistical analysis.Henneberg M, Ulijaszek SJ, Body frame dimensions are related to obesity and fatness:  lean trunk size, skinfolds and body mass index, American Journal of Human Biology, Accepted 21 April 2009.

Henneberg M, Louw GJ, 1998 Results of a cross-sectional survey of growth of urban and rural "Cape Coloured" schoolchildren:
Anthropometric  and simple functional tests, American Journal of Human Biology 10, 73-85

Reliability of anatomical identification from images (may be done by several students, each studying different aspect)

Supervisor: Maciej Henneberg

CCTV images are becoming frequently used as evidence in serious crime investigations and trials. Anatomical experts comparing bodies and faces shown on CCTV images with bodies and faces of known suspects rely on their general knowledge of anatomical variation in drawing conclusions as to similarity of offenders shown on CCTV images and suspects.  Such conclusions are challenged in courts as  not being a reliable source of identification.

This project would require a student to obtain series of resembling CCTV images photographs of persons (predominantly young adult males) in various items of clothing and headgear. These pictures would have to be taken at various angles and distances to the person and blurred to match the average quality of CCTV. About 20 persons would have to be photographed obtaining about 20 photographs of each person. Randomised photographs would be presented to an experienced forensic expert (MH) who would be asked to tell which photographs are of the same person. Results will be analysed statistically to indicate reliability of  CCTV image identifications.

There is no literature on this subject as yet beyond court proceedings transcripts in cases R v Murdoch, R  v Alrekabi, R v
Pera,  R v Nylander, R v Osborne.

Decrease in human cranial capacity in recent times

Supervisor: Maciej Henneberg

Although human brain size increased over the 5 million years of hominin evolution, in the historic times (approx. last 5 thousand years) the brain size decreased by about 10%. It is not clear whether this trend has been stopped, reversed, or is still continuing in modern times. The project would require simple craniometric measurements of head length, width and height to be collected on a sample of several hundred adults born at various years during the last century. It can also be carried out by analysis of MRI or CT scan images, but these are difficult to obtain.

Henneberg M, Budnik A, Pezacka M, Puch AE, 1985, Head size body size and intelligence intraspecific correlation in Homo sapiens species, Homo 36 207-218
Henneberg M, 1988, Decrease of human skull size in the Holocene, Human Biology 60:395-405
Henneberg M, Steyn M, 1993, Trends in cranial capacity and cranial index in Subsaharan Africa during the Holocene, American Journal of Human Biology 5:473-479 Henneberg M, Steyn M, 1995 (1997)Diachronic variation of cranial size and  shape in the Holocene : A manifestation of hormonal evolution, Rivista di Antropologia 73, 159-164
Henneberg M, 1998 Evolution of the human brain: Is bigger better ?, Experimental and Clinical Physiology and Pharmacology 25, 745-749

Associate Professor William Breed
Tel. - 8303 5743.
email - william.breed@adelaide.edu.au,
Dr Rachel Gibson
Tel - 8303 1023
email - rachel.gibson@adelaide.edu.au
Dr Eleanor Peirce
Tel. - 8303 5191;
email: eleanor.peirce@adelaide.edu.au,
Mario Ricci (Tel. - 8303 6294,
email: mario.ricci@adelaide.edu.au

Unisexuality among indigenous vertebrates
Mark Adams
email:Adams.Mark@saugov.sa.gov.au

Potential Honours projects for Reproductive Biology for 2010

What is the molecular structure of the coat that surrounds the eggs of Australian native mice and rats?

The time at which a male gamete, or spermatozoon, comes together, and fuses with, a female gamete, egg or oocyte is a unique event in biology as it is the time at which new life begins. In mammals in order for this to occur a spermatozooon has to pass up the female reproductive tract from its site of deposition and then pass through a complex extracellular glyocoprotein coat, the zona pellucida, that surrounds the egg. In order for zona penetration to take place the spermatozoon has to first bind to the outer surface of the zona pellucida and, only after this can it pass through the zona pellucida, fuse with the cell membrane of the egg, and enter the oocyte cytoplasm. For investigating the molecular details of these events in mammals studies have largely been carried out on the house mouse (Mus musculus) which has been the classic model mammalian species.  However it has recently become apparent that the house mouse, unlike most other mammals, including humans and laboratory rats (Rattus norvegicus), does not express one of the zona pellucida genes, ZP4, where it is, uniquely, a pseudogene (Boja et al, 003 278 pp34189-34202; Lefievre et al. 2005, Human Reproduction 19 pp1580-1586; Conner et al.,2005, Human Reproduction vol 20 pp1148-1152). Sperm-zona binding may therefore differ in the house mouse from that in other mammalian species. This may explain some of the unexpected findings where the knockout of two genes whose expression gives rise to proteins that occur on the sperm surface involved in sperm-zona binding (those of acrosin and galactosyltransferase), does not result in infertility.  In Australia there are a diverse array of mouse and rat species some of which are part of the lineage that includes the laboratory rat whereas others, e.g. Hopping mice and Water rats, are not part of this group and may be more closely related to the house mouse. In this proposed study we intend to use these Australian rats and mice to determine how widespread the expression of the ZP4 gene is across the mouse and rat lineages. The extent of the molecular divergence of this gene, if expressed within this group, will also be determined. In particular we intend to determine whether the occurrence of ZP4 as a pseudogene is unique to house mice. For this, our working hypothesis is “THAT THE LACK OF EXPRESSION OF ZP4 GENE IS UNIQUE TO THE LABORATORY MOUSE AND THAT, AS A CONSEQUENCE, THIS SPECIES IS AN INAPPROPRIATE MODEL FOR A STUDY OF SPERM-EGG INTERACTIONS IN OTHER MAMMALIAN SPECIES INCLUDING HUMANS.” This project is an extension of a recently completed PhD project in our laboratory by Dr. Christine Swann. Use will be made of the DNA already extracted from numerous species of Australian rats and mice that is at present stored in a freezer at The Evolutionary Biology Unit at The South Australian Museum. Primers will be designed based on the ZP4 of the laboratory rat. PCR amplification will then be carried out using standard techniques and the reaction products sequenced and the sequences aligned by eye using the published sequence for the laboratory rat.
The results of this study will give insight into the evolution of the zona pellucida glycoproteins in rodents and may also indicate whether the house mouse or laboratory rat is closer phylogenetically to the Old Endemic rodents of Australia (with Drs. Steve Cooper, South Australian Museum, and Chris Swann, School of Dentistry).

Do marsupial eggs exhibit polarity and, if so, does this determine the site of sperm-egg binding and entry?

The eggs (=oocytes) of placental mammals appear to have randomly distributed organelles within the cytoplasm with the site of sperm binding and fusion being randomly located except for the cell membrane overlying the meiotic spindle to which sperm binding and fusion cannot occur. By contrast eggs (=oocytes) of other vertebrates are polarised and with a localised site for sperm binding and penetration. What about the eggs (=oocytes) of marsupials? There is at present contradictory evidence for cytoplasmic polarity and whether localisation of the site for sperm binding and penetration occurs. We have obtained many mature eggs from a diverse array of marsupial species and we plan to use this material to determine whether polarity is present in the oocyte cytoplasm and whether this relates to the site of sperm binding, fusion and entry.

Why are the testes of the hopping mouse so tiny?

Comparative studies of testis size across species of native Australian rodents have shown that the Spinifex hopping mouse, Notomys alexis, has remarkably small testes that are an order of magnitude smaller than those of most rodent species of similar body mass (see Bauer and Breed 2008 Journal of Zoology 274: 349-356) as well as having highly variable spermatozoa (Bauer and Breed 2006 Reproduction Fertility and Development 18: 797-605). These reproductive traits suggest that hopping mice either lack of genetic heterozygosity, and/or exhibit a monogamous mating system with resultant low levels of intermale sperm competition. Using tissue samples that we have recently obtained from a wild population of hopping mice near Roxby Downs in northern South Australia we wish to use microsatellite markers to genotype the individuals so that the population structure and incidence of multiple paternity can be determined (with Dr. Steve Cooper, South Australian Museum).

Possible Honours/PhD Projects for Gut Microbiome Research Group 2010

1. Targeted Therapies for Cancer and the Gastrointestinal Tract

In recent years, the use of targeted anti-cancer therapies as a treatment for cancer, either by themselves or in conjunction with cytotoxic chemotherapy or radiotherapy, has increased markedly. The main classes of targeted therapies are monoclonal antibodies and small molecules. Although the therapeutic use of targeted therapies for cancer has been highly effective in slowing disease progression and improving disease-free survival, they have also been shown to cause mucositis. Mucositis is the damage caused by chemotherapy, radiotherapy and targeted therapies to mucous membranes of the alimentary tract (AT). Furthermore, this damage causes pain and ulceration, vomiting, bloating and diarrhoea, depending on the area of the AT affected. Mucositis impairs patients' quality of life and threatens the effectiveness of the anticancer treatment in that it is dose limiting. Moreover, targeted therapy drugs have the potential to cause mucositis because they are not solely active on malignant cells but can cross-react with receptors in other parts of the body. Furthermore, the AT has been identified as a major site of targeted therapy-induced toxicity. The aim of this proposed project is to further understand how targeted therapies cause mucositis. Students will be exposed to a wide range of techniques including: a retrospective clinical case study of targeted therapies, cell culture, immunocytochemistry, western blotting and real-time PCR.

References:

1. Gibson RJ & Keefe DMK (2006) Cancer chemotherapy-induced diarrhoea and constipation: mechanisms of damage and prevention strategies. Supportive Care in Cancer; 14(9): 890-900.
2. Keefe DMK & Gibson RJ (2007) Mucosal injury from targeted anticancer therapy. Supportive Care in Cancer; 15(5): 483-490.

2. Investigation of chemotherapy-induced changes to mucin expression in the rat gastrointestinal tract

The normal microflora of the gastrointestinal tract (GIT) is a highly complex ecosystem consisting of both aerobic and anaerobic bacteria. The gastrointestinal microflora has a number of key functions including protection and metabolism of: bilirubin, intestinal mucins, pancreatic enzymes, fatty acids, bile acids, cholesterol and steroid hormones. Other functions of the gastrointestinal bacteria include nutrient processing, regulation of intestinal angiogenesis and immune functions. The gastrointestinal microflora and mucins are known to be affected by chemotherapy and may be important factors in determining the severity of chemotherapy-induced diarrhoea and mucositis. Unfortunately, it is not yet known how these factors fit into the model of alimentary mucositis. Therefore by understanding the role of the gastrointestinal microflora and mucins in the development of chemotherapy-induced diarrhoea, these could become future therapeutic targets for mucositis treatment, by altering microflora with antibiotics or probiotics, or targeting the pathways involved in mucin gene expression. The aim of the present study is to determine the time course of changes in gastrointestinal microflora, mucin composition and distribution following methotrexate treatment in the DA rat. Students will be exposed to a wide variety of techniques including: real time PCR, immunohistochemistry, microbiological techniques, and histopathological staining.

References:

1. Stringer AM, Gibson RJ, Logan RM, Bowen JM, Yeoh ASJ, Burns J & Keefe DM (2007). Chemotherapy-induced diarrhoea is associated with changes in the luminal environment in the DA rat, Experimental Biology & Medicine, 232(1):96-107.
2. Stringer AM, Gibson RJ, Logan RM, Bowen JM, Yeoh ASJ, & Keefe DM (2007). Chemotherapy-induced mucositis: the role of gastrointestinal microflora and mucins in the luminal environment, Journal of Supportive Oncology, (in press).
3. Gibson RJ & Keefe DMK (2006). Cancer chemotherapy-induced diarrhoea and constipation: mechanisms of damage and prevention strategies, Supportive Care in Cancer, 14(9): 890-900.

3. Chemotherapy-induced changes in the tongue

Mucositis of the oral cavity is reported as the most unpleasant side effect of cancer treatment for patients. During very severe mucositis, ulcers develop on the tongue which makes alimentation impossible, interferes with speaking and swallowing and is extremely painful. It is very costly to manage patients with severe oral mucositis, and there is currently very limited options for prevention and treatment. The events leading up to ulceration have been described in the mucositis pathobiology model, but to date, the time course of changes that occurs in the tongue remains uncertain. The aim of this study is to conduct a detailed time course analysis of changes that occur to the tongue following different chemotherapeutic agents, including 5-Fluouracil, Methotrexate and Irinotecan. Students will be exposed to immunohistochemistry, routine histological and histopathological techniques, and TUNEL assays

References

1. Logan, R.M., Bowen, J.M., Stringer, A.M., Gibson, R.J., Sonis, S.T., and Keefe, D.M.K., (2008). Serum levels of NF- B and pro-inflammatory cytokines following administration of mucotoxic drugs, Cancer Biology and Therapy (in press).
2. Logan, R.M., Bowen, J.M., Stringer, A.M., Gibson, R.J., Sonis, S.T., and Keefe, D.M.K., (2008). Is the pathobiology of chemotherapy-induced alimentary tract mucositis influenced by the type of mucotoxic drug administered? Cancer Chemotherapy and Pharmacology (in press)
3. Logan RM, Gibson RJ, Bowen JM, Stringer AM, Sonis ST, Keefe DM. Characterisation of mucosal changes in the alimentary tract following administration of irinotecan: implications for the pathobiology of mucositis. Cancer Chemother Pharmacol. 2007 Aug 17 (in press).
4. Gibson, R.J., Cummins, A.G., Bowen, J.M., Logan, R.M., Healey, T and Keefe, D.M.K., (2006). Apoptosis occurs early in the basal layer of the oral mucosa following cancer chemotherapy, Asia-Pacific Journal of Clinical Oncology, 2(1): 39-49.

• Thermoregulatory rhythms in the lizard, Tiligua rugosa.

Possible Honours/PhD Projects for Neurobiology Research Group 2010

Ultrastructural and molecular changes in Choroidal epithelial cells in traumatic brain injury and the effect of acetazolamide treatment.

The choroid plexuses are highly vascular cauliflower-like structures that projects into the ventricles of the brain. Their surface is covered with a single layer of modified ependymal cells, joined by tight junctions, and are known as the choroidal epithelial cells (CECs). Since the microvessels in the core of the choroid plexus are fenestrated, the CECs form the true barrier between the blood and the CSF. The CECs are the main producers of the CSF and selectively express AQP-1 water channel proteins, which are implicated in the production of the CSF, and CSF volume is a critical factor in the regulation of intracranial pressure (ICP). One of the main deleterious complications of traumatic brain injury (TBI) is the increase in ICP. A previous study on TBI has demonstrated severe ultrastructural changes in CECs (Ghabriel et al, 2009).

The aims of the current project are to determine if the administration of acetazolamide, a carbonic anhydrase inhibitor drug used to reduce CSF production in chronic cases of increased ICP, will (a) alter the expression of AQP-1 water channels in CECs, and (b) minimise the ultrastructural changes in CECs seen after TBI. This project will increase our understanding of structural and molecular events that occur in acute cases of TBI for better patients’ management and outcome.

Ghabriel MN, Zdziarski IM, Leigh C, Vink R (2009) Changes in the blood-CSF barrier in experimental traumatic brain injury. Acta Neurochir suppl, Ch 45 (in press).

Supervisor: A/Prof. Mounir Ghabriel
Co-supervisor: Prof. Robert Vink
(This project would be suitable for two concurrent students)

Dr Julie Haynes
Tel. - 8303 5769.
email - julie.haynes@adelaide.edu.au

• Comparative microstructure of skin
• Aluminium toxicity in koalas

Dr Jaliya Kumaratilake
Tel. - 8303 5478.
E-mail - jaliya.kumaratilake@adelaide.edu.au

• Age associated changes in coronary arteries of bovine
  

Dr Jeff Trahair
Tel. - 8303 5483.
E-mail - jeff.trahair@adelaide.edu.au)

Mechanisms of Follicular Atresia

Dr Jeff Trahair
Dr Helen Irving-Rodgers (O&G)

In the mammalian ovary, oocytes are found within structures called follicles and at birth the ovary contains my thousands of non-growing primordial follicles. Every day a few of these follicles are activated and begin growing, the oocyte enlarges and the granulosa cells which surround the oocyte replicate.  After puberty ovulation can occur, however the vast majority of oocytes do not ovulate but are destroyed in a process called follicular atresia.  Atresia occurs via mechanisms for apoptosis, or programmed cell death, and is characterised by nuclear condensation and fragmentation, cleavage of chromosomal DNA and packaging of the dead cells into apoptotic bodies which are removed by phagocytosis  
Analysis of follicular atresia can be done by several methods including flow cytometry, ELISA and classic histology. Although histology is a routine, widely used and reliable method of the detection of atresia, flow cytometry may be more sensitive and able to detect early stages of apoptosis (Blondin et al. 1996). Our own studies have shown that in the cow there are two histologically distinct types of healthy (Irving-Rodgers et al. 2000), as well as two types of atretic follicles (Irving-Rodgers et al. 2001).  Importantly, one type of healthy follicle has been shown to have oocytes of better quality than the other (Irving-Rodgers et al. 2008).  We hypothesize that the follicles with poorer quality oocytes are at an early stage of atresia.  Follicles will be harvested from ovaries collected at an abattoir, and a sample of the follicle processed for histological classification of follicle type.  Granulosa cells will be collected from the remainder of the follicle and prepared for analysis by flow cytometry.    

Blondin P, Dufour M, Sirard M (1996) Biol Reprod 54, 631-637
Irving-Rodgers HF, Rodgers RJ (2000) J Reprod Fert 118, 221-228
Irving-Rodgers HF, van Wezel IL, Mussard ML, Kinder JE, Rodgers RJ (2001) Reproduction 122, 761-775
Irving-Rodgers HF, Morris S, Collett RA, Peura TT, Davy M, Thompson JG, Mason HD, Rodgers RJ (2008) Human Reproduction 24, 936-44

Role of the Extracellular Matrix in Follicular Development

Dr Jeff Trahair
Dr Helen Irving-Rodgers (O & G)

The ovary produces eggs and hormones, and these functions are dependent upon growth and development of follicles and corpora lutea within the ovary. Control of these processes is externally via hormones, or internally by growth factors and extracellular matrix. In particular our laboratory focuses on the role of extracellular matrix in regulating ovarian function as this has been poorly studied. We use molecular and cellular biology approaches. This area is important as extracellular matrix can be used to regulate ovarian cell function in vitro, as well as aiding in the understanding of ovarian diseases including infertility and hormone imbalances. Recently we discovered that the follicular basal lamina structure is related to the quality of the oocyte in the follicles (1) and we are hunting biomarkers of such follicles with a view to improving success or assisted reproductive technologies. We also discovered that a specialized extracellular matrix, focimatrix, is not only developmentally regulated in follicles but may be part of the mechanism by which a dominant follicle is selected to ovulate (2). Currently we do not understand how one follicle is selected or gains dominance over other follicles as a means of controlling ovulation rate, and our discovery could be valuable in unravelling this phenomenon.

References:

1. Irving-Rodgers HF, Morris S, Collett RA, Peura TT, Davy M, Thompson JG, Mason HD, Rodgers RJ (2009) Phenotypes of the ovarian follicular basal lamina predict developmental competence of oocytes. Human Reprod. 24, 936-944
2. Irving-Rodgers HF, Harland ML, Sullivan TR and Rodgers RJ (2009) Studies of granulosa cells maturation in dominant and subordinate bovine follicles: Novel extracellular matrix focimatrix is co-ordinately regulated with cholesterol side-chain cleavage CYP11A1. Reproduction 137, 825-834.

 

• Bone tissue remodelling
• Fatigue damage in bone and its repair.
• Structural and biomechanical changes of cancellous bone with ageing and pathology.
• Molecular determinants of cancellous bone architecture.
• Osteocytes and bone remodelling.


further information

 

Dr Chris Jones
Tel: -8303 4526
E-mail: chris.jones@adelaide.edu.au

The effects of low-load fatigue on glycated trabecular bone

Supervisors: Dr Chris Jones (Anatomical Sciences), Dr Ian Parkinson (IMVS)

Diabetic patients have an increased risk of vertebral compression fracture, which is often an atraumatic event caused by repetitive application of
low-level compressive loading e.g. activities of daily living. It has been proposed that the increased sugar in tissues causes glycation of collagen
fibrils, leading to brittleness of bones.

This project aims to measure the effects of glycation on the mechanical properties and microscopic appearance of vertebral trabecular bone. Cubes of bone will be glycated in ribose, then loaded repetitively in compression in a mechanical testing device. The mechanical properties of the bone will be recorded, and fatigued bone will also be examined using microCT analysis.

It is hoped this project will shed light on the fracture risk in diabetic patients, and possibly lead to ways of treating and/or preventing fracture.

 

Dr Ian Johnson
Tel: -8303 5988
E-mail: ian.johnson@adelaide.edu.au

Associate Professor Mounir Ghabriel
Tel. - 8303 5481.
email - mounir.ghabriel@adelaide.edu.au

Mechanisms underlying adult motoneuronal death

Motor Neurone Disease (MND) is a fatal condition of later life characterised by motoneuronal loss. Its cause is unknown and there is no cure. Clinical trials of drugs in MND have so far been based on studies of motoneuronal death in embryonic or newborn animals because there is very little information on motoneuronal death in adults. This project will look at the time-course and immunocytochemical features of motoneuronal death in the facial nucleus of adult rats. It will build upon our previous observations that 80% of adult motoneurones are lost 1 month after facial nerve avulsion. In this project, the period of maximum motoneuronal death prior to 1 month will be identified so that more detailed studies can be undertaken using antibodies to identify molecules involved in the response of motoneurones to axonal injury and the process of cell death. As a control, the facial nerve will be crushed in other rats, since this procedure does not cause motoneuronal death, but a response by the motoneurones which is results in axonal regeneration and reinnervation of the facial muscle. By comparing the response of adult motoneurones to nerve crush and nerve avulsion, information will be obtained that will help us understand mechanisms by which the motoneurones survive or die.  The project will involve microneurosurgery, stereology and immunocytochemistry.

Reading

1. Aperghis, M., Johnson, I.P, Cannon, J. Yang, S.Y. & Goldspink, G. (2004). Different levels of neuroprotection by two insulin-like growth factor-1 splice variants. Brain Research 1009: 213-218.
2. Moran, L.B. & Graeber, M. B. (2004). The facial nerve axotomy model. Brain Research Reviews 44: 154-178.
3. Rothstein, J.D. (2009). Current hypotheses for the underlying biology of Amyotrophic Lateral Sclerosis. Annals of Neurology supplement 1: 53-59.