Malignant fibrous histiocytoma in the area of the head and neck]

Although malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma of adult life, it is fairly rare in the head and neck region (3-6%). Between 1983 and 1991 8 patients with MFH in the head and neck region have been observed and treated at the ENT-department of the University of Tübingen. 5 patients have been operated (laryngopharyngeal localization), 2 patients underwent irradiation (unresectable fast growing T4-tumors of the pharynx and thyroid) and one female patient refused further therapy after two resections elsewhere. Operated patients showed no evidence of disease 2-8 years after resection (all margins have been controlled histologically). Both irradiated patients died 4 respectively 2 months after full (70 Gy) and incomplete (17 Gy) radiotherapy without visible positive effects. Both patients developed pulmonary metastasis. Since MFH can grow in thin layers along musculaoponeurotic structures the exact size is not always demonstrable by ultrasound, CT or MR scans. Metastasis occur in up to 40%, preferentially in regionary lymph nodes, in lung, liver and skeletal system. These phenomenon requires a full pretherapeutic staging. Histologically MFH is sometimes hard to distinguish from other tumors as for example various sarcomas and pleomorphic carcinoma. Therefore, immunohistochemical (mesenchymal markers) and electron microscopical investigations are advised. Resection with exact histological controll of all margins is the therapy of choice. We experienced that laryngeal MFH (n = 3) can be resected without laryngectomy under certain circumstances. Although unsuccessfull in our two cases, according to the literature, radiotherapy should be administered in unresectable cases. Depending on localization and size of MFH long survival, in single cases healing, of this disease is possible by surgical treatment.     

Stoffwechseluntersuchungen am Hund vor und nach Hypophysektomie

Ohne Zusammenfassung     

Distribution of cholinergic neurons in the chick spinal cord during embryonic development. Comparison of ChAT immunocytochemistry with AChE histochemistry.

The location of cholinergic neurons was studied during the development of the chick embryo spinal cord. A comparison between choline acetyltransferase (ChAT) immunocytochemistry and acetylcholinesterase (AChE) histochemistry was performed. ChAT-positive neurons could be detected only from embryonic day 9 (E9) onwards by the FITC technique and from E12 onwards by the PAP technique. These neurons were located mainly in the medial and lateral motor columns in the ventral horn of the gray matter and some of them were observed in the intermediate region of the spinal cord. AChE-containing cell bodies were much more numerous than the ChAT immunoreactive ones and were distributed in the ventral horn of the gray matter, the intermediate gray region and mostly off the apical part of the dorsal horn. ChAT should provide a reliable and specific marker for cholinergic neurons.     

Deep dermal burn injury results in scarless wound healing in the ovine fetus

Early to mid-term fetuses heal cutaneous incisional wounds without scars; however, fetal response to burn injury has not been ascertained. We present a fetal model of thermal injury and subsequent analysis of fetal and lamb response to burn injury. A reproducible deep dermal burn injury was created in the fetus by application of water at 66 degrees C for 7 seconds, and at 82 degrees C for 10 seconds to the lamb. Macroscopically, the area of fetal scald was undetectable from day 7 post injury, while all lamb scalds were readily identified and eventually healed with scarring. Using a five-point histopathology scoring system for alteration in tissue morphology, differences were detected between control and scalded skin at all stages in lamb postburn, but no difference was detected in the fetal model after day 7. There were also large differences in content of alpha-smooth muscle actin and transforming growth factor-beta1 between control and scalded lamb and these differences were statistically significant at day 14 (P < 0.01). This novel model of fetal and lamb response to deep dermal injury indicates that the fetus heals a deep burn injury in a scarless fashion. Further elucidation of this specific fetal process of burn injury repair may lead to improved outcome for patients with burn injury.     

Fluorescent In situ hybridization allows rapid identification of microorganisms in blood cultures

Using fluorescent in situ hybridization (FISH) with rRNA-targeted fluorescently labelled oligonucleotide probes, pathogens were rapidly detected and identified in positive blood culture bottles without cultivation and biotyping. In this study, 115 blood cultures with a positive growth index as determined by a continuous-reading automated blood culture system were examined by both conventional laboratory methods and FISH. For this purpose, oligonucleotide probes that allowed identification of approximately 95% of those pathogens typically associated with bacteremia were produced. The sensitivity and specificity of these probes were 100%. From all 115 blood cultures, microorganisms were grown after 1 day and identification to the family, genus, or species level was achieved after 1 to 3 days while 111 samples (96.5%) were similarly identified by FISH within 2.5 h. Staphylococci were identified in 62 of 62 samples, streptococci and enterococci were identified in 19 of 20 samples, gram-negative rods were identified in 28 of 30 samples, and fungi were identified in two of two samples. Thus, FISH is an appropriate method for identification of pathogens grown in blood cultures from septicemic patients.