Defect in mitochondrial functions in damaged human mitral valve

Mitochondrial diseases are a heterogeneous group of disorders in which a primary mitochondrial dysfunction is proven by morphological, biochemical, and genetic examinations. The mitral valve has important function in the regulation of blood flow from one chamber to another. Often, the mitral valve becomes abnormal with age, in Rheumatic fever or it is abnormal from birth (Congenital) or it can be destroyed by infection i.e. bacterial endocarditis and needs replacement. Myocardial function depends on energy produced by mitochondria and in any of these disease conditions, mitochondrial functions and enzyme activities may be impaired. With this in view, we analyzed the relationship between preoperative clinical conditions (as per New York heart Association) and extent of mitochondrial enzyme activities in damaged Human mitral valve in two types of heart disease such as Rheumatic Heart Disease (RHD) and Bacterial Endocarditis (BE). Thirty nine Patients undergoing cardiopulmonary bypass (CPB) for routine valvular heart surgery were included in the study. Controls included 11 normal porcine mitral valve samples without any evidence of heart disease. Mitochondrial enzymes like cytochrome oxidase (COX), succinate dehydrogenase (SDH), malate dehydrogenase (MDH), citrate synthase (CS) and ATPase were determined. Mitochondrial COX, SDH, CS and Total ATPase activities were significantly decreased in disease condition like BE and RHD when compared with control (P<0.001). On the other hand as per New York Heart Association (NYHA) preoperative clinical classification, all the mitochondrial enzymes were significantly (p<0.05) impaired in class IV as compared with NYHA class I, II and III. Present study shows that impairment in the mitochondrial enzymes activities are more pronounced in bacterial endocarditis (BE). It also indicates that damage to mitochondrial enzymes are most pronounced in NYHA class IV.     

Cardioprotective response to chronic administration of vitamin E in isoproterenol induced myocardial necrosis: Hemodynamic,biochemical and ultrastructural studies

The present study evaluated the cardioprotective potential of vitamin-E by studying its effect on hemodynamic parameters, lipid peroxidation, myocyte injury marker and ultrastructural changes in model of isoproterenol-induced myocardial necrosis in rats. Wistar albino male rats (150–200 g) were randomly divided into saline, ISP control, and vit E groups. Vitamin E group was administered vitamin E at a dose of 100mg/kg/day while saline and ISP control groups received saline orally for one month. On 29^th and 30^th day, ISP (85 mg/kg, sc) was administered at an interval of 24 h to vit E and ISP control rats. On 31^st day, rats of all groups were anesthetized and hemodynamic parameters were recorded. At the end of experimentation, animals were sacrificed; hearts were excised and processed for biochemical and ultrastructural studies. ISP administration produced marked cardiac necrosis as evidenced by significant decrease in my ocardial creatine kinase-MB as well as increase in malonaldialdehyde levels. ISP-induced myocardial necrosis resulted in myocardial dysfunction as evidenced by significant depression in heart rate and mean arterial pressure in the ISP control group as compared to saline control. Salient ultrastructural changes including extensive loss of myofibrils, muscle necrosis, loss of mitochondria, and formation of several intracytoplasmic vacuoles and lipid droplets further confirmed the ISP-induced myocardial damage. However, subsequent to ISP challenge, vit E treatment significantly preserved the myocardium by restoring myocardial CK-MB activity, inhibiting the ISP-induced lipid peroxidation and ultrastructural changes. Additionally, pre-and co-treatment of vit E prevented the deleterious ultrastructural changes caused by ISP. These beneficial effects of chronic vit E treatment also translated into significant restoration of the altered hemodynamic parameters. The present study clearly demonstrated the cardioprotective potential of vit E at dose of 100 mg/kg in ISP-induced model of myocardial necrosis in rats. The significant restoration of altered hemodynamic parameters, myocardial CK-MB activity, prevention of ISP-induced rise in lipid peroxidation and ultrastructural changes may confirm its cardioprotective effect.     

The triad-iodine deficiency,hyperlipidaemia, high coronary risk— in a ‘maternal-neonate’ population of rural Africa

In order to see the pattern of changes in differential serum lipid and lipoprotein fractions as a risk marker of coronary complication in paired ‘maternal—neonate’ blood samples in an iodine deficient zone, 26 pregnant women and their corresponding new born infants at term delivery from the iodine deficient Bassa region of Plateau state, Nigeria were assessed and the results were compared with those seen in a similar 44 group of women and their newborns assessed in non lodine deficient region of Jos. The serum thyroid function and lipid and lipoprotein profiles were determined by ‘ELISA’ and ‘enzymatic’ methods respectively. Urinary iodide excretion level was also measured in 14 pregnant women in Bassa, 23 pregnant women in Jos and 16 non pregnant control from Jos. Results indicate that the pregnant women assessed in Bassa were iodine deficient (P<0.01) and their thyroid status was strikingly reduced as reflected by a drop in serum level of T4/TBG ratio (P<0.01) and a rise in TSH (P<0.005) in comparison to that seen in Jos. There was marked hypertriglyceridaemia and total hypercholesterolaemia (P<0.005), with differential significant rise in LDL cholestotol fraction (P<0.005) in the women assessed in Bassa as compared to Jos. The HDL cholesterol however dropped less significantly in the group (P<0.05) with a concurrent marked rise (P<0.001) in the serum ratio of LDL cholesterol/HDL cholesterol, total cholesterol/HDL cholesterol and triglycerides/HDL cholesterol in the lodine deficient group. A similar pattern of changes were seen in the corresponding neonates in the Bassa group as compared to Jos group. It is concluded that the pregnant women and their newborn offsprings living in a longstanding environmental iodine deficiency run a higher risk of developing coronary complications than those living in non endemic region. It is striking that such newborns surrounded by a continued state of lodine deficient may at a later adult-period of life develop marked risk of coronary complication and other features of hyperlipidaemias associated with varying thyroid insufficiency and accompanied iodine deficiency disorders. Prophylaxis measures as intervention has been highlighted.     

From 5 million to 20 million a year: The challenge of scale,quality and relevance in India’s TVET

In the first decade of this century, India became one of the world’s fastest growing large economies, and began to face serious skill-related shortages of workers. Its TVET system has not responded adequately to the growth in demand for semi-skilled and skilled workers. This article describes six sets of reforms that India’s educational planners and policy-makers must put into place if these shortages are not to constrain India’s ability to benefit from the demographic dividend.     

Self‐regulated learning ability of Chinese distance learners

This study reports on self‐regulated learning (SRL) of Chinese distance learners by using a structured SRL scale. SRL of adult and lifelong learners is a well‐researched area, though its application within distance education is a new area of investigation. Open and distance learning lean heavily on self‐learning and self‐learning resources, though interaction at designated learning centers and online learning platforms is occasionally offered. In China, there is still persistence of the age‐old teacher‐centric model of teaching‐learning; and, within distance education offered largely by the radio and television universities, there is insistence for regular tuition classes at designated branch schools. At the backdrop of understanding and enhancing SRL of Chinese distance learners, the authors took up this research to find out the elements and levels of SRL ability among Chinese distance learners. Based on factor analysis (on 357 students for item analysis and on 600 distance learners for structural validity of the initial 117‐item scale), a standardized 54‐item Self‐regulated Learning Ability Scale was finalized and administered on a random sample of 2738 undergraduate learners (1630 males and 1108 females) from the Open Distance Education Centre of Beijing Normal University, P.R. China, doing an online course during 2009–10. The sample came from either senior high school (grade 12) or junior college (grade 14). Data on four dimensions of SRL—planning, control, regulating and evaluation—were analyzed using ‘t’ test for variables of gender, level of education and age. Results indicated that all the participants had above‐average levels of SRL in all the four dimensions of planning, control, regulating and evaluation. In so far as gender was concerned, male distance learners were better in SRL than female distance learners, especially in control (ie, content and resources) and all the evaluation dimensions. Though no age difference was found, students from junior colleges had better planning, regulating and evaluating abilities than those who came from senior high schools. These results have been discussed in the context of current changes in Chinese distance/online education and also in relation to the age‐old Chinese culture of learning. The results will also have implications for designing distance and online learning generally.     

Needs for and utilization of OER in distance education: a Chinese survey

The recent developments within open educational resources (OERs) and open licensing have generated considerable interest among distance educators since open and distance learning is supposed to be the largest consumer/user of and contributor to OER. In China, given the policy of development and use of elaborate courses, conversion of radio and television universities into open universities, establishment of the China Open Resources for Education, and adoption of Creative Commons by the Chinese government, there seems to be further expansion of OER movement in the country. Against this backdrop, it was imperative to know how distance education/open university teachers use OERs and what constraints they face in doing so. This study reports a structured questionnaire and open-ended interview findings on all the 74 teachers of the Beijing Open University for four variables: awareness, needs, utilization, and constraints. The findings show that while the teachers were generally aware of OERs, they misunderstood all web resources as OER; the Chinese elaborate courses dominated the perception and use of OER; and those who used OER mainly required it for teaching content, relevant research, and for adopting teaching methods. Searching for OER, choosing appropriate OER and copyright issues were the common constraints to effective use of OER. These results have been discussed further in relation to international research studies on OER, the context of Chinese distance/open university education, and the Chinese OER policy.     

Curative effect of <Emphasis Type="Italic">Cynodon dactylon</Emphasis> against STZ induced hepatic injury in diabetic rats

The aim of the study was to ascertain the role of ethanolic extract of Cynodon dactylon against hepatic complications in streptozotocin (STZ) induced type 2 diabetic models. Effect of the pre identified most effective dose of 500 mg/kg body weight was studied on hepatic injury caused by chemically induced diabetes by 55 mg/kg body weight i.p. injection of STZ in male Wistar rats. The dose of 500mg/kg body weight given once daily for 14 days reduced the levels of serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, alkaline phosphatase, creatinine and urine sugar significantly (P<0.05) with increase in total protein, haemoglobin and body weight was increased. High LD₅₀ validates its high margin of safety.     

A biochemical study on variability of Superoxide dismutase,Catalase and Glutathione peroxidase in dry cleaners

Several chemicals which induce cytotoxicity are broadly classified into three types and they are organophosphate, organochlorine and carbomate compounds. Perchloroethylene has been clearly identified as a carcinogen in experimental animals and it’s a very common carcinogen used for dry clean purpose. Hence, in the present study, blood samples from dry cleaners were taken, Superoxide dismutase, Catalase and Glutathione peroxidase activity was estimated in blood samples of dry cleaners. There was a significant increase in the activity of Catalase, Glutathione Peroxidase, Superoxide Dismutase in dry cleaners of chronically exposed to perchloroethylene as compared to controls. The increased activities of antioxidant enzymes may be a compensatory regulation in response to increased oxidative stress induced by perchloroethylene.     

Enzyme vs. extremozyme

Extremozymes that function in the extreme environmental conditions of temperature, pressure, pH, and salinity are of great importance for industrial processes and scientific research. Apart from understanding the principle behind the stability of such enzymes, there has been considerable effort to isolate enzymes from extremophiles (organisms that live in extreme environmental conditions) as well as modify enzymes from mesophiles (organisms that live in normal environmental conditions) to convert them into extremozymes.