ALIT Ltd, Ukraine
Bhaviks research interests are within two areas: Neurochemistry and Electroanalytical applications of carbon based materials. The research activities that are currently being perused are shown bellow:
1. Chemical Characterisation of Synaptogensis
Understanding the process of communication between neurones in the brain is an important problem in both basic physiology and the understanding of disease. The role that neurotransmitters play during the formation of synapses is currently unknown. We will use boron-doped diamond microelectrodes, which have been well developed by Prof Greg M. Swain with novel signal processing techniques to understand the roles played by co-released neurotransmitters (serotonin, nitric oxide) and pH during neuronal regeneration and synaptogenesis in culture and intact CNS preparation. Investigations will be made using the simple model system, the CNS of pond snail Lymnaea stagnalis which provides the only means to understand the process of synaptogenesis. We also aim to carry out long-term (days) and intracellular recordings from regenerating neurones in the intact CNS system.
2. Monitoring Neurochemical Changes in the Gastrointestinal track
Serotonin is an important signalling molecule in the gut and is located in the myenteric plexus and in enterochromaffin (EC) cells that reside in the intestinal mucosal layer. The EC cells are sensory transducers that release and contain more than 80 % of the body''s serotonin content. We have developed a stable protocol using boron-doped diamond microelectrodes to detection real-time overflow of serotonin (Patel et al; Analyst, 2007) to provide a means of understandingt he EC cell and thier contribution to gastrointesinal function. We have studies the changes that are associated with serotonin overflow during development (Bian et al; Gastroenertology, 2007), ageing and physiological disease states.
Alterations in Neurotransmitter signalling from irratible bowel disease tissue
This work is in collaboration with Tom Hestor, Dr Gianluca Marcelli and Mr Chris Chan
We have recently also been looking to the role of Melatonin and nitric oxide in the gatrointestinal tract, which for the frist chemical we have been the first to identify its presence within the mucosal lining of the gut. We have established and are developing new and novel experimental sensing methodologies and techniques and theroretical models to study the changes in irritable bowel disease (IBD) patients
3. Understanding the effects of neuronal ageing
This work is in collaboration with Mark Yeoman
Ageing is associated with changes in the efficacy of synaptic transmission in the brain. Efficacy of synaptic connections maybe lost due to problems in transmitter synthesis, release or detection by the target cell. An understanding of the underlying mechanisms of such deficits may provide useful insights into managing the health care needs of an ageing population. We have chosen to use a simple model system, the CNS of the pond snail Lymnaea stagnalis as a means of trying to understand the causes and consequences of CNS ageing. The brain of Lymnaea stagnalis is relatively simple compared to that of a mammal consisting of 11 ganglia and a total of about 25000 neurones. The main advantage of this system is that the neurones that comprise the nervous system are large allowing the same neurones to be identified reproducibly from one animal to the next allowing an analysis of ageing to occur at the level of the single neurone. We are focused on determining nitric oxide and serotonin release from identified neurons in vitro and study the process of neuronal regeneration between younger and older animals.
4. Signal Processing techniques for in vivo application
In vivo or in vitro monitoring of neurotransmitter dynamics offers novel insights to various physiological or pathological states such as the effect of drugs or the changes caused by neurodegenerative diseases (Alzheimer’s, Parkinson''s, etc.) in chemical signalling. Electrochemical sensing methodologies, such as fast-scan cyclic voltammetry, have contributed significantly to this research offering the opportunity for very localised measurements with sub-second temporal resolution. Despite these advantages, the current state of electrochemical sensing methodologies allows monitoring of one neurotransmitter, commonly dopamine, and it has been difficult to apply the same principles for multiple-neurotransmitter sensing. Given the fact that neurons very often contain more than one neurotransmitter, we have recently devised methods for extending electrochemical measurements towards real-time multiple-neurotransmitter sensing. In this project we seek to apply these novel techniques to biological preparations to gain an insight in the dynamics of various analytes such as dopamine, serotonin, noreadrenaline and ascorbic acid in their interplay within the biological matrix in invertebrate and mammalian models.
5. Novel Carbon Stationary Phases for Chromatographic separation
Current high performance liquid chromatography (HPLC) stationary phases have poor stability over a wider pH range (pH 1-14) and short effective lifespan. Advances have arrived with the revival of car bon and zirconia based chromatography columns. We have looked at using novel carbon materials (pyrolysed carbon, nano-porous diamonds) as a novel stationary phase for chromatographic separations. We have focused on understanding the separation behaviour of these material s under both normal phase and reverse phase separation systems. The effect of pH and elevated temperature on chromatographic separation is also being investigated.
Prof Greg M. Swain, Michigan State University, USA
Prof. R. Mark Wightman, University of North Carolina at Chapel Hill, USA
Dr Xiaochun Bian, Michigan State University, USA
Dr Anne Andrews, Pennsylvania State University, USA
James J. Galligan, Michigan State University, USA
Dr Mark S. Yeoman, University of Brighton
Prof Naweed I. Syed, University of Calgary, Canada
Mr Chris Chan, Royal London Hospital
Dr Gainluca Marcelli, Kings College London
Prof. Sergey Mikhalovsky, University of Brighton
Research Student Supervision
Chau,R, In vitro monitoring of 5-HT levels during gastrointestinal disease
Cheung,C, Understanding the role of NO during cellular communication
Lwin,A, Analytical methods for the determination of ATP in the gastrointestinal tract