β-Lactam antibiotics in the treatment of neuroborreliosis in children: Preliminary results

Summary In vitro -lactam antibiotics like ceftriaxone and penicillin G sodium have been shown to be active againstBorrelia burgdorferi. Results of quantitative determinations of both antibiotic substances in the CSF for children are limited. Seventy-five children (median age 96 months, range 10 to 176 months) with probable or definite neuroborreliosis were treated with ceftriaxone (1×50–90 mg/kg/day) or penicillin G sodium (4×80,000–120,000 IU/kg/day) intravenously. On day 10 of therapy levels of penicillin G sodium (1, 1.5, 2, 3, 4, 5, or 6 h after i.v. administration), and ceftriaxone (1, 2, 4, 6, 12 or 24 h after i.v. administration) in serum and CSF were measured with a micro agar diffusion bioassay. Results demonstrate that after 5 h penicillin G sodium in CSF was above the minimal inhibitory concentration (MIC) but after 6 h penicillin G sodium levels were below the determination limit in 60% of the cases. All ceftriaxone results in CSF — even after 24 h — were above MIC. Penicillin G sodium serum values ranged from 46.6 to 0.1 mg/l (1 to 6 h post dose) and ceftriaxone serum values from 261 to 5 mg/l (1 to 24 h post dose). The role of penicillin G sodium and ceftriaxone and administration intervals of both antibiotics in the therapy of neuroborreliosis in children are discussed.

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-Lactam Antibiotika zur Behandlung der Neuroborreliose im Kindesalter: Vorläufige Ergebnisse

Zusammenfassung Ceftriaxon und Natrium-Penicillin G sind gegenBorrelia burgdorferi in vitro wirksam. Zur Pharmakokinetik beider Substanzen im Liquor cerebrospinalis von Kindern ist hingegen wenig bekannt. 75 Kinder im Alter von 10 bis 176 Monaten (Median 96) mit einer definitiven oder möglichen Neuroborreliose wurden intravenös mit Ceftriaxon (1×50–90 mg/kg/Tag) oder Penicillin G (4×80000–120000 I.E./kg/Tag) behandelt. Am 10. Therapietag wurden die Liquor-Spiegel von Penicillin G (1, 1.5, 2, 3, 4, 5, oder 6 Stunden nach Gabe) bzw. Ceftriaxon (1, 2, 4, 6, 12, oder 24 Stunden nach Gabe) in Serum und Liquor aus gepaarten Proben mittels einer Mikroagar Diffusions-Methode gemessen. Die Ergebnisse zeigen, daß Penicillin G 5 Stunden nach Gabe noch über der minimalen Hemmkonzentration lag, daß aber 6 Stunden nach Gabe die Konzentration des Antibiotikums in 60% der Liquorproben bereits unterhalb der Meßgrenze lag. Die Ceftriaxon Liquorspiegel lagen durchwegs über der MHK — auch noch 24 Stunden nach der letzten Gabe. Die Serumkonzentrationen von Penicillin G lagen zwischen 46,6 und 0.1 mg/l, die Serumkonzentrationen von Ceftriaxon zwischen 261 und 5 mg/l. Die vorgestellten Ergebnisse werden im Hinblick auf den Stellenwert der beiden Antibiotika in der Therapie der Neuroborreliose im Kindesalter diskutiert.

     

Intraocular silicone lenses in silicone oil: an experimental study

Background: To evaluate a potential effect of silicone oil on flexible silicone intraocular lenses, four lenses (STAAR AA-4203) were stored in silicone oil under sterile conditions for periods between 1 month and 3 years. Method: The edge and surface of the lenses were examined by scanning electron micrography and the findings compared with a lens of the same model which had been stored in Ringer's solution for 2 years. Results: After 1 year of silicone oil exposure, droplets of different sizes adherent to the surface of the lens were found. These changes proceeded to a wave-like appearance of the surface after 2 and 3 years of storage, so that a continuous layer of silicone oil polymers is probably covering the intraocular lens. Conclusion: Optical interference has to be considered a possibility if it turns out that the droplets cannot be removed during silicone oil evacuation. Consequently silicone intraocular lenses without hydrophilic preparation of the surface should not be implanted in eyes undergoing combined anterior and posterior segment surgery with silicone oil tamponade or in eyes with high risk for vitreoretinal complications.The authors state that they have no proprietary interest in the marketing of the products mentioned herein or competing products     

Characterization of human lymphocyte antigen class I antigen-processing machinery defects in renal cell carcinoma lesions with special emphasis on transporter-associated with antigen-processing down-regulation.

The HLA class I antigen-processing machinery (APM) plays a crucial role in the generation of peptides from endogenously synthesized proteins and in their presentation to cytotoxic T lymphocytes. The potential role of defects of APM components in immune escape mechanisms used by malignant cells has prompted us to analyze their expression in renal cell carcinoma (RCC) lesions with special emphasis on TAP because of its critical role in the loading of HLA class I antigens with peptides. Immunohistochemical staining of 51 formalin-fixed RCC lesions and autologous normal renal epithelium detected transporter associated with antigen processing (TAP)1 and tapasin deficiencies in 63 and 80% of the tumor lesions. Impaired low molecular weight protein (LMP)2 and LMP7 expression was found in 73 and 33% of the RCC lesions analyzed, respectively. In contrast to the high frequency of APM component down-regulation, HLA class I heavy chain and beta(2)-microglobulin defects were detected in only 12 and 10% of the lesions, respectively. Concomitant TAP1 and LMP2 deficiencies were found in approximately 57% of RCC lesions, whereas a coordinated down-regulation of all APM components occurred only in 5% of the tumor specimens analyzed. The presence of APM defects was independent of tumor stage and grade but varied significantly among the RCC subtypes. TAP abnormalities do not appear to be attributable to structural alterations because no mutations in TAP1 were detected in TAP1-deficient RCC lesions. These data suggest that TAP defects in RCC lesions are caused by regulatory abnormalities. Therefore, T-cell-based immunotherapy may benefit from the administration of cytokines that up-regulate TAP expression.     

Individual interviews and focus groups in patients with rheumatoid arthritis: a comparison of two qualitative methods

Purpose  

To compare two different approaches to performing focus groups and individual interviews, an open approach, and an approach based on the International Classification of Functioning, Disability and Health (ICF).     

Importance of material evaluation prior to the construction of devices for in vitro techniques

The development and validation of new in vitro methods in the field of toxicology have gained more importance in recent years due to stricter guidelines for animal testing, especially in the European Union. Consequently, advances in the construction of technical devices for the exposure of cell or tissue cultures to test substances are necessary. Here, to obtain reliable results, it is important to exclusively use materials that do not interfere with the cell viability. Thus, similar to the biomaterials testing of medical devices which is regulated in the Directive 93/42/EEC, the biocompatibility of the materials has to be verified prior to the construction of such devices. We present here a novel approach for biomaterials testing which allows the quantitative and qualitative assessment of cytotoxicity of material samples.Stainless steel and silicone are often used for laboratory equipment, due to their high chemical, thermal and mechanical resistance. However, our results highlight that some types of silicone may have adverse effects on cultured cells. Moreover, special methods for the surface treatment of metals may also be a critical factor for in vitro devices. Therefore, the testing of all materials coming in contact with cell cultures is highly recommended.