Lesions and characteristic injury patterns caused by high-voltage fault arcs.

Exposure to high-voltage electric arcs as a result of an accident or by means to commit suicide can affect people's health and cause death. There are characteristic external findings that can be found on external examination. These include extensive skin burns, periorbital recesses or "crow's feet," vapor deposition of conductor material, known as metallization, and tightly spaced, roundish, crocodile skin like burns. The Institute of Legal Medicine of the Rostock University Medical Center recorded 16 deaths caused by exposure to electricity between 1990 and 2018. Six of these deaths were caused by exposure to high-voltage electric arcs and five of these deaths (83 %) showed crocodile skin like burns and one had periorbital recesses burns on the face as a result of a fault arc. To our knowledge, the present paper is the first report describing the frequent occurrence of crocodile skin like burns due to high-voltage fault arcs.

Neuropil pattern formation and regulation of cell adhesion molecules in Drosophila optic lobe development depend on synaptobrevin.

To investigate a possible involvement of synaptic machinery in Drosophila visual system development, we studied the effects of a loss of function of neuronal synaptobrevin, a protein required for synaptic vesicle release. Expression of tetanus toxin light chain (which cleaves neuronal synaptobrevin) and genetic mosaics were used to analyze neuropil pattern formation and levels of selected neural adhesion molecules in the optic lobe. We show that targeted toxin expression in the developing optic lobe results in disturbances of the columnar organization of visual neuropils and of photoreceptor terminal morphology. IrreC-rst immunoreactivity in neuropils is increased after widespread expression of toxin. In photoreceptors, targeted toxin expression results in increased Fasciclin II and chaoptin but not IrreC-rst immunoreactivity. Axonal pathfinding and programmed cell death are not affected. In genetic mosaics, patches of photoreceptors that lack neuronal synaptobrevin exhibit the same phenotypes observed after photoreceptor-specific toxin expression. Our results demonstrate the requirement of neuronal synaptobrevin for regulation of cell adhesion molecules and development of the fine structure of the optic lobe. A possible causal link to fine-tuning processes that may include synaptic plasticity in the development of the Drosophila CNS is discussed.

Controlled multiplex PCR of enterotoxigenic Clostridium perfringens strains in food samples.

A controlled multiplex polymerase chain reaction (PCR) for the detection of Clostridium(C.) perfringens enterotoxin gene (cpe) was established and compared with an in vitro antigenic detection method. Thecpe PCR and the classical method of electric immunodiffusion gave identical results. The predicted specific amplicon of the cpe gene was generated from all of the tested enterotoxigenic C. perfringens strains. In contrast, cultures of any other Clostridium species tested by PCR were negative (100% sensitivity, 100% specificity). Addition of an alphatoxin (plc) gene specific PCR as an in process control reaction was performed in order to prevent false negative PCR results. The PCR detection limit was 0.5 ng of genomic C. perfringens DNA per ml of bouillon culture. By contaminating minced meat with C. perfringens reference strains, the multiplex PCR was established as a tool for routine diagnostic laboratories. The detection limit was approximately 3.0x10(5)C. perfringens cells per gram meat. The results demonstrate the multiplex PCR as an easy, specific, sensitive and time saving diagnostic procedure. Application of this improved method should enhance the knowledge concerning epidemiological aspects of food borne diseases caused by enterotoxigenic C. perfringens.

Strain differentiation of Clostridium perfringens by bacteriocin typing, plasmid profiling and ribotyping.

Bacteriocin typing, plasmid profiling and ribotyping were used to type 34 food and patient Clostridium perfringens isolates from 10 food poisoning cases, respectively, outbreaks. In nine cases/outbreaks bacteriocin patterns showed identical main groups. Subgroups differed within all cases/outbreaks. Plasmid profiles were identical for all isolates within each of three outbreaks. In eight food poisoning cases and outbreaks, all the ribotypes of each food and stool isolate were found to be identical. All three typing methods give valuable results for the characterization of C. perfringens beyond the species level. Bacteriocin typing represents a suitable addition to plasmid typing, particularly since the results do not show any correlation between losses of plasmids and changes in bacteriocin sensitivity patterns. Ribotyping was found to be a suitable tool to determine the genetic relationship of C. perfringens isolates in the context of food-borne poisoning.

Quantitative investigations into the elimination of in vitro-obtained spores of the non-pathogenic Clostridium butyricum strain CNRZ 528, and their persistence in organs of different species following intravenous spore administration.

Before the Clostridium tumour assay can be applied to the diagnosis of cancer, we sought to investigate--within the framework of a biopharmaceutical safety test--the organ persistence of test spores of Clostridium butyricum CNRZ 528. We found that non-pathogenic spores obtained in vitro, like pathogenic native spores, escape phagocytosis in various organs up until about 2 years, as tested by anaerobic cultures. The elimination of spores depended on the species of animal, the spore dose and the organs investigated. In rabbits, one week after injection, we recovered clostridial spores from blood and spleen cultures more rarely than from liver and lung. The half-life of blood clearance in patients was one day or, at half the spore dose, two days. That deep tissues of healthy animals are not normally sterile became evident in rabbits after sporadic isolation and characterization of non-administered saccharolytic and proteolytic clostridial species. During a 10-year observation period, the rate of obtainment of viable spores by in vitro cultures lessened; however, for administration of the spores in clinical phase I and phase II studies, the spore quality was acceptable.

[Streptococcus-induced syndrome of toxic shock (streptococcal toxic shock syndrome)]. / Streptokokkenbedingtes Syndrom des toxischen Schocks (Streptococcal Toxic Shock Syndrome).

Report on the first case of streptococcal toxic shock syndrome in the GDR. The patient was a 54-year-old female. One week before admission to the hospital she cut her finger. The day before admission to the hospital she presented with a painful left shoulder. Demarcation followed, and Streptococcus pyogenes (group A streptococci) was isolated from this area. The temperature rose to more than 40 degrees C and she became confused, hypotensive and anuric. There was evidence for disseminated intravascular coagulation. She died 23 h after admission. Clinical course and laboratory parameters resembles staphylococcal toxic shock syndrome, except a diarrhoea. The streptococcal strain produced a large amount of erythrogenic toxin type B (more than 20 ng/ml), but not erythrogenic toxins A or C. Erythrogenic toxins of Streptococcus pyogenes seem to play the same role in the development of streptococcal toxic shock syndrome as the toxic shock syndrome 1 (TSST-1) in staphylococcal toxic shock syndrome.

[Rapid diagnosis in Clostridium perfringens wound infections]. / Schnelldiagnostik bei Clostridium perfringens-Wundinfektionen.

Prompt and early microbiological differential diagnosis is essential for clinical presumptive diagnosis of gas gangrene. The differential diagnosis includes clostridial myositis (gas gangrene), clostridial cellulitis and other gas producing infections. Examination of Gram preparation (bacterioscopy) and detection of the etiologic agent in muscle specimens are necessary for diagnosis. Clostridium perfringens has been shown as the causative organism of gas gangrene. A method is reported which allows the screening and identification of Clostridium perfringens from clinical specimens in a few hours. Using a medium yielding optimal growth and toxin production, pure cultures are centrifuged and subjected to rapid tests (detection of beta-galactosidase, phospholipase C).

[Necrotising enteritis (author's transl)]. / Die Enteritis necroticans.

4 cases of severe necrotising enteritis are dealt with. The small intestine was affected 3 times, the colon once, One patient died after resection of the affected bowel segment. In 2 additional cases a large resection of the small intestine became necessary. One patient was treated conservatively. The bacteriological evidence of Clostridium perfringens type C in the intestinal wall allows the assumption of a primarily bacterial genesis of this disease. Its aetiology, clinical and pathological-anatomic picture and the therapy are being discussed.

[Investigations on the characterization of a clostridial strain for tumour diagnosis (author's transl)]. / Untersuchungen zur Charakterisierung eines Clostridienstammes für die Krebsdiagnostik.

Careful delineation of a clostrial strain for human tumour diagnosis as against oncolytic tissue-active clostridial strains should be obligatory. We investigated the possibility to differentiate Clostridium butyricum CNRZ 528 (Bergère) against three different strains kept in our institute by means of biological, biochemical and by phage typing procedures. In addition, consistency in the control of half-technological spore production is required. It could be confirmed by this study that oncolytic properties of clostridial strains are biologically testable with adequate sensitivity in the hamster A Mel 3 tumour model. By means of typing procedures, we were able to clearly differentiate between Clostridium butyricum CNRZ 528 on one hand and Clostridium oncolyticum M 55 as well as Clostridium butyricum Jena H 8 on the other. The results of the tests are unsuitable for identifying Clostridium butyricum CNRZ 528 or Clostridium butyricum McClung 1672 A, respectively, nor can we distinguish Clostridium oncolyticum M 55 from Clostridium butyricum Jena H 8.

Three-parameter probability distribution density for statistical image analysis.

Statistical analysis of 2-D image data or data gathered from a scanning radiometer requires that both the non-Gaussian nature and finite sample size of the process be considered. To aid the statistical analysis of this data, a higher moment description density function has been defined, and parameters have been identified with the estimated moments of the data. It is shown that the first two moments may be computed from a knowledge of the Weiner spectrum, whereas all higher moments require the complex spatial frequency spectrum. Parameter identification is carried out for a three-parameter density function and applied to a scene in the IR region, 8-14 microm. Results indicate that a three-parameter distribution density generally provides different probabilities than does a two-parameter Gaussian description if maximum entropy (minimum bias) forms are sought.

Statistical filter for image feature extraction.

Edge extraction techniques have become important as a preprocessing step in extraction of image features for the purpose of image segmentation, object identification, and bandwidth compression. The use of conventional edge extractors such as Sobel and Laplacian filters results in images that in many cases have a high degree of clutter due to the natural spatial texture of the scene background. To overcome this difficulty, a statistical filter has been developed that enhances local grey level activity around objects while reducing contributions due to background. The statistical filter is employed in a neighborhood modification process where the central pixel is replaced with the third central moment computed from the surrounding neighborhood.Choice of the third central moment is due in part to the fact that it is a function of the scene within the neighborhood rather than the power spectral density (Wiener spectrum) of the neighborhood. Application of the filter requires no prior knowledge, and pixels within the filter window may be chosen in random order due to the statistical nature of the operation. Results of the filter applied to IR images show performance comparable with, and in some cases superior to, the Sobel and Laplacian filters most commonly used for feature and edge extraction.