CHARACTERIZATION AND INHIBITION OF POLYPHENOL OXIDASE FROM PEARS (PYRUS COMMUNIS L. CV. BOSC AND RED)

Red pears had higher PPO activity, total phenolics and chlorogenic acid concentration than Bosc pears. PPO activity and phenolics both decreased in fruits held at room temperature. pH and temperature optima for Bosc and Red pears PPOs were 5.0 and 5.5, and 20 and 23C, respectively. 4-Methylcatechol, catechol and dopamine were good substrates for PPO from both pear cultivars; however, no activity was observed with any of the mono-hydroxy substrates studied. Higher K_m and lower V_max values were observed for Bosc pear PPO. Heating at 75C for 30 min completely inactivated the enzyme from both cultivars. Heating at 55 and 65C for the same duration resulted in partial inactivation (45–60%) of this enzyme. Ascorbic acid, L-cysteine, sodium metabisulfite and thiourea effectively inhibited browning due to pear PPOs.     

CLEAR SKY SOLAR INSOLATION DATA FOR ISLAMABAD

Monthly mean values of both integrated and instantaneous clear sky solar radiation components for Islamabad territory are presented and discussed. The components include global normal, direct normal, global horizontal, direct and diffuse horizontal radiations, sunshine duration, number of clear days and ambient temperature for solar energy applications. Direct normal irradiance values are used to get clear sky sunshine duration by ab-initio. The need for replacing the conventional sunshine recorder is discussed.     

THE EFFECTS OF DIETARY α-TOCOPHEROL AND SURFACE APPLICATION OF OLEORESIN ROSEMARY ON LIPID OXIDATION AND CHOLESTEROL OXIDE FORMATION IN COOKED RAINBOW TROUT (Oncorhynchus mykiss) MUSCLE

The inhibitory effect of dietary α-tocopherol supplementation (100 and 500 mg α-tocopheryl acetate/kg diet) and an oleoresin rosemary dip on lipid and cholesterol oxidation in cooked rainbow trout ( Oncorhynchus mykiss ) during storage at 4C for 48 h was investigated. The 2-thiobarbituric acid-reactive substances (TBARS) values of cooked fish muscle increased during storage for all treatments. Dietary α-tocopherol supplementation partially inhibited lipid oxidation. Surface application of oleoresin rosemary further enhanced this protective effect. Cholesterol oxides were formed in all the samples following cooking and storage. The major cholesterol oxidation products (COPS) were identified as 7 β-hydroxycholesterol, α- and β-epoxides, and 7-ketocholesterol. Formation of COPS was reduced by dietary supplementation with α-tocopherol and surface application of oleoresin rosemary. Statistical analysis revealed a highly significant (p < 0.01) inhibitory effect of oleoresin rosemary on COPS formation.     

Use of Impella cardiac axial flow pump for cardiogenic shock (A newer alternative)–How good is the evidence?

The adverse outcomes of a ventricular heart failure (left, right or biventricular) caused by cardiogenic shock are aggravated by lung oedema and organ mal perfusion. Despite advances in medical sciences, revascularisation and mechanical hemodynamic support have proved ineffective in reducing the mortality rate in such patients. A thorough study of the data available about cardio-vascular diseases reveals that the application of conventional methods of treatment are least helpful to practically restore normal functions of heart when it experiences end-stage systolic ventricular failure. Thus, to overcome the challenges and find alternatives to address this issue, percutaneous ventricular support devices/machines were designed and successfully introduced. These devices have revolutionized the treatment of ventricular heart failures and are now in use all over the world. In this review paper a newer mechanical circulatory support (MCS) device, Impella, has been discussed and compared with a few other devices like (Intra-aortic Balloon Pump (IABP), Extracorporeal Circulation (ECLS) and Veno-arterial Extracorporeal Membrane Oxygenation (VA-ECMO). This article studies the challenges being faced during the treatment of cardiogenic shock, and thoroughly discusses the use and effectiveness of Impella Cardiac Axial Pump in each emergency. It can be said that mechanical circulatory support (MCS) device use during percutaneous coronary intervention (PCI) should be individualized based on multiple factors with a recommended use in patients with the greatest potential benefit and a relatively low risk of device-related complications. The current literature suggests that the outcomes of use of Impella and other mechanical circulatory support devices like IABP and VA-ECMO are comparable. Though there seem to be a few advantages of Impella over the others, sufficiently powered, multi-centric, randomised control trials are needed to establish its superiority.     

EFFECT OF DIETARY COMPONENTS AND SURFACE APPLICATION OF OLEORESIN ROSEMARY ON LIPID STABILITY OF RAINBOW TROUT (Oncorhynchus mykiss) MUSCLE DURING REFRIGERATED AND FROZEN STORAGE

The effect of dietary supplementation with α-tocopherol and surface application of oleoresin rosemary on the lipid stability of rainbow trout ( Oncorhynchus mykiss ) muscle during refrigerated storage (4C) and frozen storage (−20C) for 8 days and 6 months, respectively, was investigated. A significant (p < 0.05) reduction in α-tocopherol concentrations in muscle tissue during frozen storage was observed. The 2-thiobarbituric acid-reactive substances (TBARS) values of muscle samples, with or without surface application of oleoresin rosemary, increased during storage for all dietary groups. A significant (P < 0.05) interaction between dietary treatments and the time of storage was observed. Muscle tissue from fish receiving a dietary supplement of 500 mg/kg diet had the lowest TBARS values. The oxidative stability of the lipids was further improved by applying oleoresin rosemary to the surface of the fish fillets.     

EFFECT OF DIETARY VITAMIN E AND SURFACE APPLICATION OF OLEORESIN ROSEMARY ON IRON/ASCORBATE-STIMULATED LIPID OXIDATION IN MUSCLE TISSUE AND MICROSOMES FROM RAINBOW TROUT (Oncorhynchus mykiss)

The effect of dietary α-tocopheryl acetate and surface application of oleoresin rosemary on iron/ascorbate-induced lipid oxidation in rainbow trout ( Oncorhynchus mykiss ) muscle and microsomes was investigated. The 2-thiobarbituric acid-reactive substances (TBARS) values of muscle and microsomes isolated from fish fed the higher concentration of α-tocopherol (500 mg/kg feed) were smaller than those of fish fed the lower concentration (100 mg/kg feed). The protective effect of oleoresin rosemary on lipid oxidation in fish muscle was also observed. Analysis of variance revealed a significant (p < 0.01) interaction between dietary treatments and incubation time. Dietary α-tocopherol supplementation significantly increased the α-tocopherol concentration of muscle microsomal membranes, thereby increasing the oxidative stability of the membrane lipids.