Knowledge, attitudes and practices of barbers about hepatitis B and C transmission in Hyderabad, Pakistan

Hepatitis B and C virus [HBV/HCV] infections are serious global health problems. Shaving by barbers has been identified as the key risk factor for spread of HBV. We conducted a cross-sectional survey of barbers in Hyderabad city, Pakistan in 2007 to establish their knowledge and attitudes to the risk of HBV and HCV transmission and their working patterns. Observations showed that 96.2% washed razors with antiseptic after each client and 95.7% used a new blade with new clients. However, knowledge about the diseases and modes of transmission were poor and only 36.6% knew that hepatitis can be transmitted via shaving instruments. Only 3.2% of 186 barbers were vaccinated against HBV. Strategies are needed for raising awareness and regulations of barbers' practices

Some mechanical properties of a highly cross-linked, microwave-polymerized, injection-molded denture base polymer.

PURPOSE: The impact strength and the flexural properties of denture base materials are of importance in predicting their clinical performance upon sudden loading. This study compares the impact and transverse strengths and the flexural modulus of three denture base polymers. MATERIALS AND METHODS: The investigation included a relatively new microwave-polymerized polyurethane-based denture material processed by an injection-molding technique, a conventional microwave-polymerized denture material, and a heat-polymerized compression-molded poly(methyl methacrylate) (PMMA) denture material. Impact strength was determined using a Charpy-type impact tester. The transverse strength and the flexural modulus were assessed with a three-point bending test. The results were subjected to statistical analysis using a one-way analysis of variance and the Scheffé test for comparison. RESULTS: The impact strength of the microwave-polymerized injection-molded polymer was 6.3 kl/m2, while its flexural strength was 66.2 MPa. These values were lower than those shown by the two compression-molded PMMA-based polymers. The differences were statistically significant. The flexural modulus of the new denture material was 2,832 MPa, which was higher than the conventional heat-polymerized polymer but was comparable to the other microwave-polymerized PMMA-based polymer. The difference in the flexural modulus was statistically significant. CONCLUSION: In terms of the impact and flexural strengths, the new microwave-polymerized, injection-molded, polyurethane-based polymer offered no advantage over the existing heat- and microwave-polymerized PMMA-based denture base polymers. However, it has a rigidity comparable to that of the microwave-polymerized PMMA polymer.

[Use of N-benzoyl-phenylalanyl-valyl-arginine p-nitroanilide and hirudin for the detection of enzymatic activity under prothrombin acylation by citraconic anhydride]. / Ispol'zovanie N-nitroanilida N-benzonl-fenilalanil-valil-arginina i girudina dlia vyiavleniia fermentativnoi aktivnosti pri atsilirovanii protrombina tsitrakonovym angidridom.

Acylation of bovine prothrombin by cytraconic anhydride results in the formation of the thrombin active site, which provides the degradation of highly specific thrombin substrate, N-bensoyl-Phe-Val-Arg p-nitroanilide. This reaction is inhibited with hirudin, highly specific thrombin inhibitor.

[Products of bovine prothrombin citraconylation and their activation by factor Xa]. / Produkty tsitrakonilirovaniia bych'ego protrombina i ikh aktivatsiia faktorom Xa

Products of bovine prothrombin acylation by citraconic anhydride, modified to 20--90% have been obtained. Disc-electrophoresis in polyacrylamide gel in the presence of sodium dodecyl sulfate has shown that the citraconylation of prothrombin is accompanied with spontaneous activation, resulting in formation of products with molecular weights identical to those of neoprothrombin C, neoprothrombin T, profragment and fragments A and C. Spontaneous activation upon the citraconylation is never completely recovered: the reaction products always contain a fraction, corresponding in molecular weight to prothrombin. Citraconylation products possess neither coagulating, nor esterase activity. Generation of esterase activity requires the presence of an enzyme--factor Xa, which splits the 323-324 peptide bond (Arg-Ile) in the molecules of prothrombin and intermediate products of its activation. The mechanism of activation of citraconylated prothrombin products by factor Xa does not differ from the mechanism of native prothrombin activation by the enzyme. The esterase activity, which is generated after the incubation with factor Xa, is due to the building of citraconylthrombin and partly of the native thrombin; the latter may be formed at the low degree of prothrombin modification.

[Determination of the secondary prothrombin structure under different degrees of citraconylation by means of ring dichroism]. / Opredelenie metodom krugovogo dikhroizma vtorichnoi struktury protrombina pri raznoi stepeni tsitrakonilirovaniia

A process of spontaneous activation of bovine prothrombin under acylation of cytacone anhydride is studied by means of ring dichroism and disc electrophoresis in sodium dodecylsulphate. Ring dichroism data have shown that native prothrombin contains 14% of alpha-helical structures, 36% of beta-structures and 50% of random coil. Cytraconylation results in a fragmentation of native prothrombin chain and is accompanies by the decrease of alpha-helical regions in the fragments formed. Poly-L-lysine, modified by citracone anydride, does not form alpha-helical regions.