Kinetic analysis of LDL oxidation in IHD and IHD risk subjects in Indian population

High plasma concentration of low-density lipoprotein (LDL) is associated with increased risk of atherosclerosis. Modified forms of LDL, especially oxidized LDL play a major role in its pathogenesis. This article gives detailed insight into the kinetics ofin vitro LDL oxidation by copper at different concentrations in normal and high-risk group subjects. Basal level of oxidatively modified LDL was significantly higher in ischaemic heart disease (IHD) and IHD hyperlipidemic subjects compared to normolipidemic and, hyperlipidemic control subjects, respectively. Derivatization of amino groups of apo-lipoprotein as monitored by estimating free amino groups concentration, was significantly higher in high-risk group and established IHD cases. Kinetics of oxidation was studied with two different concentrations of CuSO₄ (2.5 mM and 7.5 mM). thiobarbituric acid reactive substances (TBARS) level increases with time, and up to 95% oxidation was observed in 8 hr. About 60–65% less free amino groups were observed in native-LDL isolated from IHD patients compared to normal subjects. Study also showed an increase in two oxidative products studied, 20α-OH-cholesterol and 4-cholesten-3-one with oxidation time accompanied by corresponding decrease in LDL cholesterol. Increase in oxidative species was more evident in high-risk group and IHD patient. Basal level of oxidatively modified LDL measured in terms of TBARS was significantly higher in present study, strongly support that the extent of LDL oxidation monitored as TBARS and FAG level in circulating-LDL could be used as risk marker for high risk group.     

Pro-oxidant and anti-oxidant status in patients of sickle cell anaemia

The role of oxidant damage to red cells in sickle cell anaemia has been of interest in recent years. Although, available reports suggest that sickle cell erythrocytes are susceptible to endogenous free radical mediated oxidant damage there remains discrepancy in the status of antioxidant enzymes and antioxidant vitamins in these patients. In view of this, 107 cases of sickle cell anaemia (36 ‘SS’ and 71 ‘AS’ pattern—as confirmed by haemoglobin electrophoresis) were subjected to analysis of malondialdehyde, ascorbic acid, superoxide dismutase and albumin. The results were compared with 54 age and sex matched healthy controls. The results indicate a marked increase in lipid peroxidation and superoxide dismutase levels in both ‘SS’ and ‘AS’ types of sickle cell anaemia as compared to controls. Although no difference was observed in the levels of albumin in these groups the levels of ascorbic acid were significantly depleted in sickle cell anaemia patients. The results are indicative of enhanced lipid peroxidation along with imbalance in the pro-oxidant and antioxidant status in patients of sickle cell anaemia.     

Hypoxia-Induced Inflammatory Chemokines in Subjects with a History of High-Altitude Pulmonary Edema

High altitude hypoxia is known to induce an inflammatory response in immune cells. Hypoxia induced inflammatory chemokines may contribute to the development of high altitude pulmonary edema (HAPE) by causing damage to the lung endothelial cells and thereby capillary leakage. In the present study, we were interested to know whether chronic inflammation may contribute to HAPE susceptibility. We examined the serum levels of macrophage inflammatory protein-1α (MIP-1α), monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 in group (1) HAPE Susceptible subjects (n = 20) who had past history of HAPE and group (2) Control (n = 18) consist of subjects who had stayed at high altitude for 2 years without any history of HAPE. The data obtained confirmed that circulating MCP-1, MIP-1α were significantly upregulated in HAPE-S individuals as compared to the controls suggestive of chronic inflammation. However, it is not certain whether chronic inflammation is cause or consequence of previous episode of HAPE. The moderate systemic increase of these inflammatory markers may reflect considerable local inflammation. The existence of enhanced level of inflammatory chemokines found in this study support the hypothesis that subjects with past history of HAPE have higher baseline chronic inflammation which may contribute to HAPE susceptibility.     

Chemical composition of biliary calculi from Kanpur region

Gallstones from 24 female patients were subjected to quantitative chemical analysis. Two main categories of stones were identified: (1) Ten cholesterol stones with 93.38% cholesterol and only 0.17% bilirubin. (2) Mixed stones with cholesterol below 65%. They were sub-divided in two groups: (a) Six stones having 0.5% bilirubin and (b) Eight stones having 0.5% bilirubin. The calcium of cholesterol and mixed stones was comparable while phosphorus contents in cholesterol stones were low by over 30% in mixed stones.     

Glycosylated haemoglobin-a diagnostic tool in pregnant diabetics

Blood samples of 40 pregnant women were analysed for glycosylated haemoglobin (HbA1c) and blood sugar. The patients were followed up till delivery and their obstetric outcome was analysed in conjunction with the glycaemic profile and the level of glycosylated haemoglobin. Group I comprising the normal pregnant women showed a mean HbA1c of 6.23% at 20–40 weeks of gestation. In contrast the diabetic pregnant women (group II) at the same gestation demonstrated an HbA1c of 9.4%. Further group IIA of gestational diabetic women showed an HbA1c of 8.97% and group IIB comprising the overt diabetics had HbA1c of 9.86%. The mother who delivered a congenitally malformed child had an elevated HbA1c of 10.4% during pregnancy. Seven cases of macrosomia were reported and the mean HbA1c of their mothers at 20–40 weeks of gestation was found to be 9.91%. Six mothers delivered infants who developed respiratory distress syndrome (RDS) soon after birth and all these six had elevated HbA1c with a mean of 8.9%. Abortions were also associated with elevated HbA1c of 10.3% antenatally. One case of still birth was reported and the mother demonstrated an elevated glycosylated haemoglobin during pregnancy. An HbA1c of 10% or more was associated with abortion, still-birth, or congenitally malformed babies.     

Phospholipid and cholesterol levels in serum and bile in cholelithiasis

Cholesterol and phospholipids were estimated in serum and bile from hepatic duct and gallbladder of twenty five patients of gallstone with functioning gallbladder (Group-I) and an equal number of patients having diseases other than of hepatobiliary system acting as control (Group-II). Group-I patients showed high serum cholesterol and low serum phospholipid levels as compared to those of Group-II. Cholesterol levels in hepatic duct and gallbladder bile were higher in Group-I than in Group-II whereas the phospholipid levels in the bile of Group-I were lower than in Group-II. The phospholipid: cholesterol ratios in hepatic duct and gallbladder bile of Group-I were 2.76 and 3.03 respectively as compared to 5.62 and 5.92 in Group-II.     

Evaluation of the changes in serum iron levels in pre-eclampsia

Serum iron levels were studied in 50 patients with pre-eclampsia and the results were compared with 50 control cases. Their serum iron levels were found to be higher than the controls. Increase in serum iron was directly proportional to the increased levels of uric acid, urea and creatinine. Mean reticulocyte counts, plasma free haemoglobin and unconjugated bilirubin levels were also higher in these patients. It is suggested that haemolysis may be a major contributory factor for the increased levels of serum iron in pre-eclampsia.     

Can Spelling Checkers Help the Novice Writer?

This paper argues that one type of text analyser—the spelling checker—can help non-proficient writers. 16 students in a Singapore classroom wrote compositions by hand for one month; the following month they composed their compositions directly on the computer. Observations of students' composing behaviours and a comparison of the lexis used in two students' hand-written and computer essays show that students use the spelling checker for two functions: (a) word-correction, in which they locate and correct some of their spelling errors, and (b) word-generation, in which they use the spelling checker to generate words that are in their receptive but not their productive vocabularies. The spelling checker benefits those students whose initial writing ability is poor and whose writing is blocked by an emphasis on the mechanical aspects of writing.