Most point-of-care tests (POCT) use swabs for sampling and/or for applying a sample on the test. A variety of swabs differing in tip materials is commercially available. Different tip materials have different chemical and physical characteristics which might influence the specimen collection and release. We investigated properties of various types of swabs used in clinical diagnostics with focusing on two kinds of analytes, DNA and proteins, which are most often used targets in POCT. As the model samples we used diphtheria toxoid NIBSC 69/017 for investigating recovery of protein analytes such as antigens and bacterial strains of Escherichia coli ATCC 25922, diphtheria toxin-producing Corynebacterium diphtheriae NCTC 10648, and the clinical isolate nontoxigenic C. diphtheriae 5820/15 for investigating the recovery of nucleic acids. We investigated four types of swabs most commonly used in clinical diagnostics in terms of absorption capacity and efficiency of release of nucleic acids and proteins. Volume uptake was measured in milligrams. For DNA release various washing out buffers were used and the amount of released DNA was measured spectrophotometrically. The amount of protein released from the swabs were examined using the Lowry assay. We observed statistically significant differences (p < 0.05) in the mean weights of absorbed liquid, in the DNA recovery and protein recovery by the four variety of swab examined. However, the efficiency of DNA and protein release was not correlated to the absorbed volume of a sample, but rather to the properties of swabs. The swab composition and structure can have a significant impact on the collection and release efficiency of a sample. Therefore, validation of POCT in relation to the used swabs for sampling is really important. The use of inappropriate swabs could lead to false negative or misleading analysis results.

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The machinery of antibiotic production by Penicillium chrysogenum PQ-96 is composed of co-located cytosolic and peroxisomal enzymes of the penicillin G biosynthesis pathway. Pexophagy and exocytosis should be currently considered as an alternative for penicillin G secretion from the mycelial cells. Penicillin G overproduction is a cellular detoxification process, protecting the mycelium from the toxicity of the antibiotic precursor. 1. Introduction. 2. Peroxisomal functions and penicillin G biosynthesis. 3. Immunoelectron microscopyof isopenicillin N synthase. 4. Ultrastructural localization of peroxisomes. 5. Pexophagy and exocytosis-secretion of penicillin G. 6. Conclusions 1. Wprowadzenie. 2. Rola peroksysomów i biosynteza penicyliny G. 3. Mikroskopia immunoelektronowa syntazy izopenicyliny N. 4. Ultrastrukturalna lokalizacja peroksyzomów. 5. Peksofagia i egzocytoza. 6. Wnioski

Purpose Vaccines adsorbed on aluminum adjuvants irreversibly lose potency after freezing and their safety is affected. To prevent the administration of such vaccines, the World Health Organization developed the Shake Test designed to determine whether adsorbed vaccines have been frozen or not. However, the Shake Test is difficult and time-consuming when routinely conducted at the place of vaccination. In this study, a modified shake test for prequalification of potentially frozen vaccines was elaborated. Materials and Methods Vaccines used in the Polish Immunization Schedule were investigated and the analysis includes an assessment of precipitation time and the influence of the container type, amount and type of aluminum compound, and a volume of vaccine dose on the precipitation time. Results Significant differences between the precipitation time of frozen and non-frozen vaccines routinely used in the Polish Immunization Schedule were observed. The precipitation time of all non-frozen vaccines was above 30 minutes. The longest precipitation time of frozen vaccines was 10 minutes. Conclusion The finding of the study can be used in practice by the personnel administering vaccines to patients. Step-by-step recommendations for the preparation of the test have been proposed in the article.