Relation of Xmn-1 Polymorphism & Five Common Indian Mutations of Thalassaemia with Phenotypic Presentation in b-Thalassaemia

Xmn-1 polymorphism is a known factor, which increases foetal haemoglobin production. Among, b thalassaemics in India five mutations are common. Disease severity was assessed based on age of presentation, age when received first transfusion and blood transfusion in ml/kg/year. Data was divided into three Xmn-1 categories, (+/+), (-/+), (-/-) and intergroup correlation was made. Mutations were divided into 2 groups, (group I) IVS 1-1 as one of its variables and (group II) without IVS 1-1. They were correlated. In Xmn-1 +/+ category 66.66% were diagnosed after one year of age, in mutations (group I) 53.57% had age of diagnosis after 1 year. 77.77% in Xmn-1 +/+ received their first blood transfusion after 1 year of age, in mutations (group I) 64.28% received their first blood transfusion after 1 year of age. About 66.66% patients in Xmn-1 +/+ category received blood <200ml/kg/year as against 72.22% in Xmn-1 -/- category. In mutations group I 57.14% received blood transfusion <200 ml/kg/year as against 68.18% in group II. It is concluded that the presence of Xmn-1 polymorphism and IVS 1-1 mutation leads to a milder phenotypic presentation causing a delay in onset of blood transfusions but dose not effect the amount of blood received /kg/year.

Raised platelet thiobarbituric acid-reacting substances in proliferative Eales' disease.

BACKGROUND: Platelets are an elective site for oxidative stress owing to their high content of polyunsaturated fatty acid. Increased lipid peroxidation and elevated platelet thiobarbituric acid-reacting substances (TBARS) signal oxidative stress. This possibly leads to retinal neovascularization in Eales' disease. METHODS: TBARS levels were estimated in consecutive cases of Eales' disease with neovascularisation (n = 26), Eales' disease without neovascularisation (n = 17) and healthy controls (n = 17). RESULTS: Platelet TBARS levels in the cases of Eales' disease with neovascularisation, Eales' disease without neovascularisation, and healthy controls were 0.66 +/- 0.1, 0.57 +/- 0.11 and 0.42 +/- 0.14 n moles TBARS formed/hour/10(8) platelets respectively. Student's t-test showed a significant increase in platelet TBARS levels in cases with neovascularisation as compared to cases without neovascularization (p < 0.05) and healthy controls (p < 0.01). CONCLUSION: The increase in platelet TBARS levels in proliferative Eales' disease is consistent with an emerging view that lipid peroxides may be associated with retinal neovascularisation.

The efflux of nor-epinephrine from platelets in genetic hypertension.

Platelets have been used as a model of sympathetic neurons to study the storage of nor-adrenaline in normotensive individuals belonging to families with essential hypertension for at least two generations. The efflux and initial efflux rate (K) of noradrenaline was determined in 36 young relatives (mean age 29.2 years) and in 20 young controls with no family history of hypertension (mean age 26.5 years). From the groups of relatives all those with definite hypertension had been excluded. Efflux and efflux rate K was significantly higher in young relatives (50.82 +/- 3.84 and 28.2 +/- 6.3) than in the controls (39.2 +/- 0.71 and 15.2 +/- 4.8). Of the relatives 25.2% had higher K values than any of the controls.