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Background: Stress echocardiography is a very useful diagnostic and prognostic test in the evaluation of significant coronary artery disease (CAD) causing inducible myocardial ischemia. Stress echocardiography has higher sensitivity and specificity as compared to exercise stress electrocardiography, and therefore, the guidelines recommend opting for the former modality over the latter. There are data suggesting that the incidence of major cardiac events is

Alkaline protease from Conidiobolus brefeldianus was efficient in unhairing various types of skins and hides. The crude protease preparation was active toward keratin-azure, elastin-orcin, azocasein, and azocoll, but did not show true collagenase activity. In addition, the crude enzyme exhibited other enzyme activities such as chondroitinase, laminarase, and chitinase. Complete hair removal of skin/hide by the protease achieved in 16–18 h. The dehaired pelt showed smooth and white appearance due to hair removal along with epidermal layer. In addition, the grain was clean and without damage in enzymatically dehaired pelts. The microscopic observation of the cross-section of dehaired goat skin and cow hide showed absence of epidermis, hair shaft with empty follicles. Enzymatic dehairing resulted in complete and uniform fiber opening in the dermis and corium region. Physical properties viz. tensile strength, elongation, and tear strength of dyed crust of enzymatically and conventionally dehaired pelts were comparable. Results were also validated on large scale with goat skins and cow hides.

The waste X-ray/ photographic films contain 1.5 - 2 % (w/w) black metallic silver which is recovered and reused. Around 18-20% of the world's silver needs are supplied by recycling photographic waste. Since silver is linked to gelatin in the emulsion layer, it is possible to break the same and release the silver using proteolytic enzymes. Alkaline protease from Conidiobolus coronatus was investigated for enzymatic hydrolysis of gelatin from waste X-ray films. At the end of the treatment, gelatin layer was completely removed leaving the polyester film clean and silver was recovered in the hydrolysate, both of which can be reused. Various parameters such as pH, temperature, enzyme concentration, time etc on silver removal from the film were studied. Gelatin hydrolysis was monitored by measuring increase in turbidity in the hydrolysate, which was accompanied by release of protein and hydroxyproline. Gelatin layer was stripped completely within 6 min with 1.35 U ml -1 of protease at 40°C, pH 10. Rate of gelatin hydrolysis increased with increased in protease concentration. The enzyme could be effectively reused for four cycles of gelatin hydrolysis. Silver in hydolysate was around 3.87% (w/w) based on total weight of sludge. Key words: Silver recovery; X-ray films; gelatin hydrolysis; alkaline protease; Conidiobolus coronatus DOI: 10.3126/kuset.v6i1.3311 Kathmandu University Journal of Science, Engineering and Technology Vol.6(1) 2010, pp60-69