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C Mainka

Publications and source records attributed to C Mainka.

10 recordsLinked to original sources
PubMed1999

No acute varicella-zoster virus replication in peripheral blood mononuclear cells during postherpetic neuralgia.

Patients suffering from postherpetic neuralgia (PHN) were investigated whether varicella-zoster virus (VZV) DNA or RNA could be detected in their peripheral blood mononuclear cells (PBMCs). Altogether 16 samples were tested by standard polymerase chain reaction (PCR) for open reading frame (ORF) 14 and ORF 29, standard and nested PCR for ORF 63, and isothermal transcription-based nucleic acid amplification (NASBA) for ORF 63 and ORF 68. By these methods neither VZV DNA nor VZV RNA could be detected. The obtained results are in contrast to those of other authors (Vafai et al., 1988; Mahalingam et al., 1995) but support the hypothesis of Bennett (1994) and Kost and Straus (1996) proposing that PHN is not caused by acute VZV replication but a consequence of neuronal damage accompanying replication of VZV in ganglia during zoster episodes.

Chickenpox↗
PubMed1998

Characterization of viremia at different stages of varicella-zoster virus infection.

Varicella-zoster virus (VZV) viremia at different stages of infection was characterized. Different approaches were used, polymerase chain reaction (PCR), isothermal transcription based nucleic acid amplification (NASBA), and immunofluorescence to describe and quantitate viral infection of peripheral blood mononuclear cells (PBMC). In patients with acute varicella 200 to 5,000 copies of the viral genome in every 150,000 PBMC were found with quantitative competitive PCR (QCPCR). With NASBA, viral transcriptional activity was detected in these cells. RNA transcribed from the immediate early gene IE 63 as well as from the late gene 68 were found, indicating a productive infection. Glycoprotein gE specific immunofluorescence visualized by confocal laser scanning microscopy revealed that only 1 in 10,000 to 100,000 PBMC was infected. T and B lymphocytes as well as monocytes expressed viral protein on their surface. Similar results were obtained with PBMC from immunocompetent zoster patients. In some cases a transient viremia was found shortly after the onset of rash, although the viral load seemed to be lower than in patients with varicella. Examination of blood samples from 16 persons with postherpetic neuralgia (PHN) signs of viral replication in PBMC were not detected. In conclusion, the data suggest that VZV viremia is a frequent event in patients with varicella and zoster, but not in those with postherpetic neuralgia. Moreover, the results indicated that subclinical reactivations occur both in immunocompromised and immunocompetent individuals.

Aged↗
PubMed1998

Subclinical reactivation of varicella-zoster virus in immunocompromised and immunocompetent individuals.

The occurrence of subclinical reactivation of varicella-zoster virus (VZV) in peripheral blood mononuclear cells (PBMC) from immunocompetent subjects >60 years old without any signs of VZV-caused illnesses, and from immunocompromised patients was investigated. Altogether, 223 samples were tested by nested ORF 63 PCR assay. In addition, all positive samples were tested by ORF 14, ORF 29 and ORF 63 PCR assays, as well as by ORF 63 and ORF 68 nucleic acid sequence-based amplification assays. In 5 samples, VZV-specific DNA, but no transcripts, could be detected. Three of them belonged to the group of >60-year-olds, 1 was HIV positive, the other was being treated with chemotherapy. The results confirm the observation of other authors that subclinical reactivation occurs in both immunocompromised and healthy individuals. The failure to detect DNA in samples taken from 2 individuals several weeks later excludes a long-lasting infection of VZV in PBMC.

Adult↗
PubMed1995

[Integrated gait analysis: a complex expert system approach to detailed data evaluation].

Integrated Gait Analysis is still not accepted as an important tool in a routine clinical environment because of its lack of assessment procedures closely based on the raw data measurements. Furthermore, an adequate treatment of the complex process of human movement is missing. This contribution is intended to successively describe the scheme of a dedicated approach for gait analysis data assessment. Therein, different technologies already discussed in the literature have been used. Some examples are given for the purpose of illustration. To provide in advance sufficiently different and well-known measurement conditions, extreme manipulations in the alignment of below-knee prostheses have been carried out. It is shown that some specific data formats consisting of subgroups of gait patterns have turned out to be important for further partial processing and for interfacing the different subsystems. However, due to data characteristics of the raw data and the lack of a well-founded a priori knowledge, some principal questions have to be left open. Therefore, on the basis of the different results presented below and their discussion, a more detailed model of the process is proposed for further research following this concept.

Artificial Limbs↗
PubMed1994

[Rabies antibody production in ferrets after immunization with four different rabies vaccines].

The Development of Rabies Antibodies in Ferrets after Injection of Four Different Types of Rabies Vaccines. Experiments aimed at proving the suitability of ferrets in the routine testing of rabies vaccines for human and animal use were carried out. A total of 40 ferrets received four vaccines, two for use in humans and two for use in animals. For the determination of rabies antibodies, blood was taken on days 28 and 56, respectively, after inoculation of the vaccines. All animals developed antibodies of more than [0.5 IE/ml] serum as determined by RFFIT. The antibody titre following injection of the vaccines for animals (A1 and A2) was 4.1 IE/ml on day 28 and 5.86 IE/ml on day 56. The antibody titre following injection of the vaccines for humans was 6.64 IE/ml on day 28 and 8.87 IE/ml on day 56. The suitability of ferrets for the potency assay of rabies vaccines is discussed.

Animals↗
PubMed1993

[Integrated gait analysis for future routine clinical use].

To describe the phenomenon of human movement by means of kinematic and kinetic measurements in a more objective manner, so-called integrated gait analysis systems have been developed. Although the commercially available equipment has already reached high technical levels, it does not play an important role in routine clinical applications. Due to this fact, the main arguments of the practitioners still address the practicability of the devices as well as the lack of meaningful software support for data assessment. The former concern has led to the integration of two KISTLER platforms beneath a treadmill belt in order to continuously capture 3D ground reaction force data. The latter one has prompted the development of an additional software kit, which statistically preprocesses the raw data set for further computations and which should prospectively allow a detailed analysis with artificial intelligence techniques. This new software becomes even more meaningful from the practitioner's point of view, because it may also be used as a stand alone unit for a preliminary assessment of gait patterns. The first part deals with the design of integrating two KISTLER platforms beneath the treadmill belt. A description of the analysis software follows, which removes noise, especially the influence of friction, from the raw data set. Thereby the 3D ground reaction force, which is originally caused by the patient while walking, is reconstructed. Preliminary results are presented. In the second part methods of automatically preprocessing the kinematic data set are focused upon.

Electromyography↗