Multidisciplinary Cardiovascular Research Centre

Dr. Ramzi Ajjan

Senior Lecturer and Consultant in Diabetes and Endocrinology

Cardiovascular and Diabetes Research

Qualifications: MD, MRCP, MMed.Sci, PhD

Email: R.Ajjan@leeds.ac.uk

Telephone: 0113 343 7475

Research Area

Mechanisms and modulation of increased thrombosis risk in diabetes

Details

Cardiovascular disease remains the main cause of mortality in diabetes and one reason is related to increased thrombosis potential in these individuals. Ajjan is responsible for a number of basic and clinical translational research projects, aiming to investigate the mechanisms for increased thrombosis risk in subjects with diabetes. Interactions between the genetic background and environmental factors are also analysed. Finally, modulation of thrombosis risk by administration of various therapeutic agents is also studied.

Recent Projects

Current principal investigator studies:

A new mechanism for impaired fibrinolysis in diabetes: the role of complement C3; Sir Jules Thorn Charitable Trust, PhD studentship: £79,000 (2011-2014)
 
A new paradigm in understanding clot formation and fibrinolysis: Molecular mechanisms for altered clot structure/function in Bb-chain genetic variants of fibrinogen; British Heart Foundation, PhD studentship: £97,263 (2010-2013)
 
Modulation of Clot Structure and Platelet Function by Aspirin in Individuals with Diabetes: The Role of Aspirin Dose and Glycaemic Control; British Heart Foundation, Project Grant: £144,200 (2010-2012)
 
Antiplatelet treatment in patients with diabetes mellitus: is there a difference between aspirin, clopidogrel and prasugrel? Elli Lilly, Investigator Led Project Grant: £161,500 (2010-2012)
 
Local CLRN clinical support grant, £101,500 (2010-2012)
 
Hypogonadism, diabetes and cardiovascular risk: effects of testosterone replacement therapy, Bayer, Investigator Led Project Grant: £23,000 (2009-2011)
 
Previous principal investigator studies:

British Thyroid Foundation, Research Award: £6,800 (2008-2009)
 
Department of Health Clinician Scientist Award: £707,000 (2005-2009)
 
Industry-sponsored Principal Investigator studies:

Glucose monitoring in diabetes; Abbott Care: £104,000 (2010-2012)
 
Continuous glucose monitoring; Abbott Care: £44,000 (2011-2012)

Publications

All

Muscogiuri G; Sorice GP; Ajjan R; Mezza T; Pilz S; Prioletta A; Scragg R; Volpe SL; Witham MD; Giaccari A (2012) Can vitamin D deficiency cause diabetes and cardiovascular diseases? Present evidence and future perspectives. NUTRITION METABOLISM AND CARDIOVASCULAR DISEASES, 22 , pp. 81-87.

Howes JM; Richardson VR; Smith KA; Schroeder V; Somani R; Shore A; Hess K; Ajjan R; Pease RJ; Keen JN; Standeven KF; Carter AM (2012) Complement C3 is a novel plasma clot component with anti-fibrinolytic properties.. Diab Vasc Dis Res, .

Scott DJA; Prasad P; Philippou H; Rashid ST; Sohrabi S; Whalley D; Kordowicz A; Tang Q; West RM; Johnson A; Woods J; Ajjan RA; Ariens RAS (2011) Clot Architecture Is Altered in Abdominal Aortic Aneurysms and Correlates With Aneurysm Size. ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY, 31 , pp. 3004-3010.

Greenhalgh KA; Alzahrani S; Price J; Strachan M; Baxter P; Standeven K; Kurdee Z; Grant P; Ajjan R; Ariens RSA (2011) Effects of B beta Arg448Lys polymorphism on fibrin clot structure/fibrinolysis and cardiovascular complications in subjects with type 2 diabetes. JOURNAL OF THROMBOSIS AND HAEMOSTASIS, 9 , pp. 141-141.

Hess K; Schroeder V; Alzahrani S; Mathai M; Howell G; Smith K; Carter AM; Marx N; Grant PJ; Ajjan R (2011) A novel mechanism for hypofibrinolysis in diabetes: the role of complement C3. JOURNAL OF THROMBOSIS AND HAEMOSTASIS, 9 , pp. 140-140.

Schroeder V; Hess K; Dobo J; Gal P; Ajjan R (2011) Complement MBL-associated serine protease-1 (MASP-1) interacts with plasma clot formation - a novel link between inflammation and thrombosis?. JOURNAL OF THROMBOSIS AND HAEMOSTASIS, 9 , pp. 27-28.

Ajjan RA; Bottomley MJ; Thanabalasingham G; Alzahrani SH; Hess K; Owen KR (2011) Maturity onset diabetes of the young is characterised by less thrombotic fibrin network structure compared with phenotypically similar type 2 diabetes subjects. JOURNAL OF THROMBOSIS AND HAEMOSTASIS, 9 , pp. 140-140.

Magwenzi SG; Ajjan RA; Standeven KF; Parapia LA; Naseem KM (2011) Factor XIII supports platelet activation and enhances thrombus formation by matrix proteins under flow conditions. JOURNAL OF THROMBOSIS AND HAEMOSTASIS, 9 , pp. 820-833.

Ajjan RA; Grant PJ (2011) The Role of Antiplatelets in Hypertension and Diabetes Mellitus. JOURNAL OF CLINICAL HYPERTENSION, 13 , pp. 305-313.

Baldo O; Eardley I; Summmers L; West R; Standeven K; Ajjan R; Mcguinness J (2010) Erectile dysfunction and cardiovascular risk: Investigating fibrin clot structure. A controlled study. JOURNAL OF SEXUAL MEDICINE, 7 , pp. 401-402.

Ariens RAS; Ajjan R; Standeven KF; de Willige US; Mutch NJ; Philippou H (2010) Role of fibrin clot structure in susceptibility to lysis. JOURNAL OF THROMBOSIS AND HAEMOSTASIS, 8 , pp. 6-6.

Schulze F; Carter AM; Schwedhelm E; Ajjan R; Maas R; von Holten R; Atzler D; Grant PJ; Boeger RH (2010) Symmetric dimethylarginine predicts all-cause mortality following ischemic stroke. ATHEROSCLEROSIS, 208 , pp. 518-523.

Shantikumar S; Ajjan R; Porter KE; Scott DJA (2010) Diabetes and the Abdominal Aortic Aneurysm. EUROPEAN JOURNAL OF VASCULAR AND ENDOVASCULAR SURGERY, 39 , pp. 200-207.

Alzahrani SH; Ajjan RA (2010) Review article: Coagulation and fibrinolysis in diabetes. Diabetes and Vascular Disease Research, 7 (4), pp. 260-273.

Imrie H; Abbas A; Viswambharan H; Rajwani A; Cubbon RM; Gage M; Kahn M; Ezzat VA; Duncan ER; Grant PJ; Ajjan R; Wheatcroft SB; Kearney MT (2009) Vascular Insulin-Like Growth Factor-I Resistance and Diet-Induced Obesity. ENDOCRINOLOGY, 150 , pp. 4575-4582.

Ajjan RA; Standeven KF; Khanbhai M; Phoenix F; Gersh KC; Weisel JW; Kearney MT; Ariens RAS; Grant PJ (2009) Effects of Aspirin on Clot Structure and Fibrinolysis Using a Novel In Vitro Cellular System. ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY, 29 , pp. 712-U196.

Abou-Saleh RH; Connell SD; Harrand R; Ajjan RA; Mosesson MW; Smith DAM; Grant PJ; Ariens RAS (2009) Nanoscale Probing Reveals that Reduced Stiffness of Clots from Fibrinogen Lacking 42 N-Terminal B beta-Chain Residues Is Due to the Formation of Abnormal Oligomers. BIOPHYSICAL JOURNAL, 96 , pp. 2415-2427.

Ajjan RA; Ariens RAS (2009) Cardiovascular disease and heritability of the prothrombotic state. BLOOD REVIEWS, 23 , pp. 67-78.

Ajjan RA; Ariëns RAS (2009) Cardiovascular disease and heritability of the prothrombotic state. Blood Reviews, 23 (2), pp. 67-78.

Ajjan R; Storey RF; Grant PJ (2008) Aspirin resistance and diabetes mellitus. DIABETOLOGIA, 51 , pp. 385-390.

Ajjan RA; Grant PJ (2008) The cardiovascular safety of rosiglitazone. Expert Opinion on Drug Safety, 7 (4), pp. 367-376.

Tan LB; Lewis NT; Ajjan R (2008) Confusion over thiazolidinedione-induced heart failure: Need for a better definition of heart failure. Expert Review of Cardiovascular Therapy, 6 (5), pp. 623-627.

Belchetz PE; Chu CE; Ajjan R (2008) Chapter 11 Autoimmunity in Turner's, Down's, and Klinefelter's Syndromes. Handbook of Systemic Autoimmune Diseases, 9 , pp. 113-134.

Ajjan RA; Grant PJ; Futers TS; Brown JM; Carter AM (2006) The association of complement C3 genotype with coronary artery disease, markers of the metabolic syndrome and C3 plasma levels. THROMBOSIS AND HAEMOSTASIS, 95 , pp. 393-394.

Ajjan R; Grant PJ; Futers TS; Brown J; Carter AM (2006) The association of complement C3 genotype with coronary artery disease, markers of the metabolic syndrome and C3 plasma levels. Thrombosis and Haemostasis, 95 (2), pp. 393-395.

Teaching Commitments

Diabetes and endocrine lead for first year medical student teaching
 
Currently supervising:
MD student (2009-2011): Fibrin clot structure/fibrinolysis and relationship to cardiac ischaemia and metabolic factors in older individuals with type 2 diabetes (writing up stage). Funded by King Fahd University, Saudi Arabia (passed July 2011).
 
PhD student (2010-2013): The molecular mechanisms for the reduced clinical efficacy of aspirin in diabetes. Funded by King Saud University, Saudi Arabia.
 
PhD student (2010-2013): A new paradigm in the relationship between clot structure and fibrinolysis: Molecular mechanisms for altered clot structure in genetic variants of fibrinogen. Funded by the BHF.
 
BSc student (2010-2011): Interaction between glycation and acetylation in diabetes.
 
BSc student (2010-2011): Inflammation, cardiovascular disease and diabetes.
 
Previously supervised:
One MSc student (passed).
 
Six BSc students (all passed; 4 First Class).

Widening Participation

Invited speaker at international meetings:

BIT International Congress in Cardiology, Shanghai-China (2010). Cardiovascular disease and dyslipidemia in diabetes: What is the optimal lipid management strategy?

Mowasat Conference in Diabetes and Metabolism, Kuwait city-Kuwait (2009). Insulin resistance, cardiovascular risk and hypogonadism.

Spanish Hypertension Society meeting, Stiges-Spain (2006). Insulin resistance and cardiovascular risk: the role of insulin sensitising agents.

Invited speaker at national meetings:

The British Cardiovascular Society-London (2009). Aspirin: an alternative mode of action and potential mechanisms for treatment failure in diabetes.

Association of British Clinical Diabetologists-Bristol (2009). Debate: Aspirin resistance in diabetes explains the lack of benefit in the primary prevention of vascular complications.

Meeting of the Oxford Centre for Diabetes, Endocrinology and Metabolism-Oxford (2009). Glycation and acetylation in diabetes.

The Royal College of Physicians-Newcastle (2008) Thyroid autoantibodies in clinical practice.

Other:

Chair at the British Endocrine Society Meeting 2007, 2010 and 2011.

Associate Editor (Diabetes and Vascular Disease Research).

Co-leader of Leeds Thrombosis and Diabetes programme group.

Head of grant reviewing Committee at Leeds Multidisciplinary Cardiovascular Research Centre.

Leading a team of: 3 research nurses, 2 technicians and 3 PhD students.

R&D lead for Diabetes and Endocrinology in Leeds.

Grant income over past 6 years >£1.35 million, publications >50 (original articles 30), H-index 20.