Suparna Roy

Comparison of Urinary and Serum CA 19-9 as Markers of Early Stage Urothelial Carcinoma

OBJECTIVES Although the glycoprotein group tumor marker CA 19-9 has been detected in both serum and urine of bladder cancer patients, information about their comparative role in screening of low grade transitional cell carcinoma (LGTCC) and high grade transitional cell carcinoma (HGTCC) is rare. MATERIALS AND METHODS In this study we measured both the urinary and serum levels of CA 19-9 in 35 LGTCC and 20 HGTCC patients by ELISA and determined the cut off value of both urinary and serum CA 19-9 levels by receiver operator characteristic curve (ROC) for both patient groups. Odds ratio (OR) for CA 19-9 was analyzed with its range at 95% confidence interval to analyze the role of this tumor marker as a screening parameter for both of these cancer types. RESULTS For urinary CA 19-9 the OR was 20.16 with an interval of 4.91-82.71 whereas for the serum CA 19-9 it was 7.5 with an interval of 2.28-24.62. CONCLUSIONS From these data we suggest that urinary CA 19-9 is a better screening parameter with optimum sensitivity and specificity than its serum counterpart for diagnosis of low grade and early stages of transitional cell carcinoma of urinary bladder. Furthermore, it can be suggested that urinary CA 19-9 can be used as better prognostic marker for LGTCC than its serum counterpart.

Role of membrane cholesterol and lipid peroxidation in regulating the Na+/K+-ATPase activity in schizophrenia

Background: Na+/K+-ATPase (NKA) activity is compromised in several neuropsychiatric disorders. Oxidative stress and membrane lipid composition play important roles in regulating NKA activity. Aims: The present study was undertaken to evaluate the effects of oxidative stress-induced membrane lipid damage and membrane cholesterol composition on NKA pump activity in schizophrenia. Settings and Design: It was a hospital-based, cross-sectional, observational study in 49 cases and 51 controls for 1 year. Materials and Methods: NKA pump activity in red blood cell membrane, serum levels of thiobarbituric acid reactive substances (TBARS), protein carbonyl (PC) adducts, and cholesterol were measured by standard spectrophotometric techniques in newly diagnosed schizophrenia patients by Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision criteria. Membrane cholesterol was analyzed by chloroform and isopropanol extraction followed by measuring the cholesterol concentration by spectrophotometric technique. Statistical Analysis and Results: Mean values for NKA pump activity, membrane cholesterol level, and serum cholesterol levels were significantly lower in the case group (P < 0.001). The activity of NKA pump was found to be directly correlated to membrane cholesterol level rather than with the serum cholesterol values. Although the NKA pump activity showed inverse relationship with the serum values of TBARS and PC products both, on multiple linear regression analysis, it was found to be significantly positively dependent on the membrane cholesterol (β = 0.268, P = 0.01) and negatively dependent on the serum TBARS (β = −0.63, P < 0.001) levels only. Conclusion: Reduced membrane cholesterol and oxidative stress-induced damage to membrane lipids play crucial roles in decreasing the NKA activity in schizophrenia. Hence, for a better prognosis and treatment, measures are required to maintain optimum levels of cholesterol in neuronal tissues along with a proper control on oxidative stress.

The Effects of Altered Membrane Cholesterol Levels on Sodium Pump Activity in Subclinical Hypothyroidism

Background Metabolic dysfunctions characteristic of overt hypothyroidism (OH) start at the early stage of subclinical hypothyroidism (SCH). Na+/K+-ATPase (the sodium pump) is a transmembrane enzyme that plays a vital role in cellular activities in combination with membrane lipids. We evaluated the effects of early changes in thyroid hormone and membrane cholesterol on sodium pump activity in SCH and OH patients. Methods In 32 SCH patients, 35 OH patients, and 34 euthyroid patients, sodium pump activity and cholesterol levels in red blood cell membranes were measured. Serum thyroxine (T4) and thyroid stimulating hormone (TSH) levels were measured using enzyme-linked immunosorbent assays. Differences in their mean values were analysed using post hoc analysis of variance. We assessed the dependence of the sodium pump on other metabolites by multiple regression analysis. Results Sodium pump activity and membrane cholesterol were lower in both hypothyroid groups than in control group, OH group exhibiting lower values than SCH group. In SCH group, sodium pump activity showed a significant direct dependence on membrane cholesterol with an inverse relationship with serum TSH levels. In OH group, sodium pump activity depended directly on membrane cholesterol and serum T4 levels. No dependence on serum cholesterol was observed in either case. Conclusion Despite the presence of elevated serum cholesterol in hypothyroidism, membrane cholesterol contributed significantly to maintain sodium pump activity in the cells. A critical reduction in membrane cholesterol levels heralds compromised enzyme activity, even in the early stage of hypothyroidism, and this can be predicted by elevated TSH levels alone, without any evident clinical manifestations.