ABSTRACT
Background: For evaluation of unexplained prolongation of PT and PTT, mixing tests forms a great diagnostic tool. On mixing equal volume of patient plasma with normal pooled plasma, if there is correction it indicates factor deficiency and non-correction indicates inhibitors.Methods: Sysmex CS-5100 Coagulometer with Pathrombin SL APTT reagent, LA1 and LA2 reagents supplied by siemens were used. All data were expressed as Mean±SD. Statistical analysis was done using unpaired students t test. A p value of <0.05 was used to indicate statistical significance in all analyse.Results: APTT with (1:1) and (4:1) mixing study for detection of factor deficiency showed a sensitivity of 91% and 92% for RI, 88% and 90% for Changs %, and 75% for Brandt correction PNP aPTT + 5 secs respectively. For Inhibitors, RI shows a sensitivity of 79% and 89%, Changs 71 and 80% and Brandt test 50% for APTT (1:1) and (4:1) mix, respectively.Conclusions: Mixing tests forms an important diagnostic tool in differentiating factor deficiency from inhibitors especially in LAC patients. This study recommends mandatory use of mixing tests in LAC cases as also advocated by BSH, ISTH and CLSI. Rosners Index is more sensitive than changes % and Brandt correction in the interpretation of mixing studies. It can be safely concluded that RI can be used as a reference method for evaluation of mixing studies and its sensitivity is greatly increased by using PP4:1 PNP. It’s a matter of debate that whether these indices can be effective with other Analysers and reagents?
ABSTRACT
Abstract This study investigated lytic enzyme activities in three indigenous Trichoderma strains namely, Trichoderma asperellum, Trichoderma harzianum and Trichoderma sp. Native Trichoderma strains and a virulent strain of Rhizoctonia solani isolated from infected bean plants were also included in the study. Enzyme activities were determined by measuring sugar reduction by dinitrosalicylic acid (DNS) method using suitable substrates. The antagonists were cultured in minimal salt medium with the following modifications: medium A (1 g of glucose), medium B (0.5 g of glucose + 0.5 g of deactivated R. solani mycelia), medium C (1.0 g of deactivated respective antagonist mycelium) and medium D (1 g of deactivated R. solani mycelia). T asperellum showed presence of higher amounts of chitinases, β-1, 3-glucanases and xylanases in extracellular protein extracts from medium D as compared to medium A. While, the higher activities of glucosidases and endoglucanses were shown in medium D extracts by T. harzianum. β-glucosidase activities were lower compared with other enzymes; however, activities of the extracts of medium D were significantly different. T. asperellum exhibited maximum inhibition (97.7%). On the other hand, Trichoderma sp. did not show any effect on mycelia growth of R. solani on crude extract.