Improved performance of PACE 2 with modified collection system in combination with probe competition assay for detecti

The Gen-Probe PACE 2 assay (GP) in combination with a modified collection system was compared with cell culture (CC) for the detection of Chlamydia trachomatis in urethral specimens from males. Analysis of discordant results was performed by PCR. The modifications, i.e., application of a more rigid swab type and a 50% reduction in the amount of transport medium, were made to improve the sensitivity of the assay. By using the modified GP on 302 urethral specimens from males, a sensitivity of 89.5% and a specificity of 100% were determined. In addition, performance of a probe competition assay on all GP samples with a result > 0.6 and < 1.0 times the cutoff factor (gray zone) detected three more true-positive samples. The sensitivity of GP in combination with the probe competition assay increased to 94.9%, with a specificity of 100%. This was identical to the performance of CC. The modified GP offers a very sensitive and specific alternative to CC

Evaluation of Clearview and Magic Lite tests, polymerase chain reaction, and cell culture for detection of Chlamydia trachomatis in urogenital specimens

The Clearview Chlamydia test (CV; Unipath Ltd., Bedford, United Kingdom), the Magic Lite Chlamydia test (ML; CIBA Corning, Medfield, Mass.), a polymerase chain reaction (PCR), and cell culture (CC) were evaluated for detection of Chlamydia trachomatis in urogenital specimens. Specimens were collected from 283 men and 724 women visiting the outpatient clinic for Sexually Transmitted Diseases at the University Hospital Rotterdam, Rotterdam, The Netherlands. ML, PCR, and CC were all performed on the same sample to prevent swab-to-swab variability. CV was performed on a separate sample. Analysis of discordant results was performed by application of the following confirmatory assays: first, PCR on th

National laboratory-based surveillance system for antimicrobial resistance: a successful tool to support the control of antimicrobial resistance in the Netherlands

An important cornerstone in the control of antimicrobial resistance (AMR) is a well-designed quantitative system for the surveillance of spread and temporal trends in AMR. Since 2008, the Dutch national AMR surveillance system, based on routine data from medical microbiological laboratories (MMLs), has developed into a successful tool to support the control of AMR in the Netherlands. It provides background information for policy making in public health and healthcare services, supports development of empirical antibiotic therapy guidelines and facilitates in-depth research. In addition, participation of the MMLs in the national AMR surveillance network has contributed to sharing of knowledge and quality improvement. A future improvement will be the implementation of a new semantic standard together with standardised data transfer, which will reduce errors in data handling and enable a more real-time surveillance. Furthermore, the

Organ specific changes in energy metabolism due to anaerobiosis in the sea mussel Mytilus edulis (L.)

1. 1. Anaerobic energy metabolism was investigated in different organs of Mytilus edulis and the whole animal. 2. 2. Succinate accumulates to high levels in most organs but remains low in the hemolymph. 3. 3. After 16 hours propionate accumulation is observed in all organs. Experimental evidence is not sufficient yet to point out organs that produce more propionate than others. 4. 4. Acetate is a minor end product. 5. 5. Acetate and propionate are found in the hemolymph in amounts equal to those in the organs. 6. 6. Animals incubated in oxygen-free seawater accumulate more end products than animals exposed to air, in the form of volatile fatty acids that are excreted into the incubation water. 7. 7. Alanine and glutamine increase in the posterior adductor muscle. Aspartate decreases in the total animal, posterior adductor muscle and gills, while in the hemolymph decrease in alanine, asparagine, serine, threonine and proline are observed

The influence of seasonal changes on energy metabolism in Mytilus edulise (L.).—III. Anaerobic energy metabolism

1. 1. Seasonal changes in the accumulation of end products after 48 hr of exposure to air and in the composition of the free amino acid pool were studied in Mytilus edulis. 2. 2. The accumulation levels of succinate and acetate showed only weak seasonal changes. 3. 3. Conversion of succinate to propionate was high in summer and virtually zero in winter 4. 4. Alanine and most other free amino acids were present in relatively high concentrations in summer and early autumn and reached minimal values in winter and early spring. 5. 5. Exceptions were glutamate, aspartate and taurine, which showed hardly an season related changes and glycine, which changed inversely to the majority of the free amino acids. 6. 6. The anaerobic formation of alanine was inversely proportional to the endogenous concentration. 7. 7. The only other free amino acids affected by anaerobiosis were glutamate and aspartate, which respectively increased and decreased under these conditions

Seasonal variations in biochemical composition of mytilus edulis with reference to energy metabolism and gametogenesis

1. 1. Seasonal changes in biochemical composition in relation to energy metabolism and to gametogenesis were studied in Mytilus edulis for nearly one and a half year. 2. 2. During the whole experimental period animals were selected from samples of the same musselbed in the Dutch Wadden Sea at intervals of about three weeks. 3. 3. The biochemical composition of total tissues and different organs was analyzed. In growing mussels a gradual increase of protein, glycogen and lipid contents was observed from spring to autumn. From November to next April the protein and glycogen content declined, whereas the lipid content remained rather constant until spawning. The observed changes are discussed in relation to environmental parameters as temperature, salinity and nutrient levels, as well as to energy production and gametogenesis. 4. 4. Hardly no seasonal variations were found in the total free amino acid concentrations from both the total tissues and different organs. However, the individual amino acids showed clear seasonal changes in all tissues investigated. The greatest fluctuations were found for taurine and glycine. These amino acids showed an inverse relation to each other. 5. 5. Seasonal changes in the accumulation of end products of anaerobic metabolism and in the composition of the free amino acid pool were found in groups of mussels exposed to air for 48 h. The observed variations in propionate and alanine accumulation as well as other compiunds involved in anaerobic metabolism are discussed in relation to temperature and salinity