[On the 150th anniversary of the birth of Friedrich Adolph Hartung (1817-1893)].
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Germany, West↗
Biomedical subjects
S Schulz
Publications and source records attributed to S Schulz.
Effects of [des-Tyr-D-Phe3]beta-casomorphin (2-5) on sleep pattern in rats.
The effects of the antidepressant-like acting peptide [des-Tyr-D-Phe3]beta-casomorphin(2-5) (Pro-D-Phe-Pro-Gly, BCH-325) on sleep were studied in rats. The rats received subcutaneous injections of BCH-325 in acute experiments (doses: 4, 20, 100, 500 and 2500 nmol/kg) and in a 10-day chronic experiment (50 nmol/kg/day). Acute administration of 20 and 100 nmol/kg enhanced wakefulness, 500 and 2500 nmol/kg enhanced paradoxical sleep, and 4 nmol/kg had no effect. Chronic administration resulted in an increase of paradoxical sleep during the first 5 days of drug treatment. Thus the sleep effects of BCH-325 differ from those of typical antidepressants and other psychotropic drugs.
Animals↗
Some aspects of gastric secretory tests in dogs for diagnostic purposes in two selected cases of stomach disease.
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Animals↗
Localization of five somatostatin receptors in the rat central nervous system using subtype-specific antibodies.
The cloning of five members of the somatostatin receptor family, sst1-sst5, as well as two isoforms of the somatostatin receptor 2, sst2A and sst2B, enabled us to generate specific anti-peptide antisera against unique sequences in the carboxyl-terminal tail of each somatostatin receptor subtype. We used these antibodies in multicolor immunofluorescent studies aimed to examine the regional and subcellular distribution of somatostatin receptors in adult rat brain. Several findings are notable: The cloned sst1 receptor is primarily localized to axons, and therefore most likely functions in a presynaptic manner. The cloned sst2 receptor isoforms exhibit strikingly different distributions, however, both sst2A and sst2B are confined to the plasma membrane of neuronal somata and dendrites, and therefore most likely function in a postsynaptic manner. The cloned sst3 receptor appears to be excluded from 'classical' pre- or postsynaptic sites but is selectively targeted to neuronal cilia. The cloned sst4 receptor is preferentially distributed to distal dendrites, and therefore most likely functions postsynaptically. The cloned sst5 receptor was not detectable in the adult rat brain, however, prominent sst5 expression was found in the pituitary. Furthermore, sst1-containing axons either co-contained somatostatin or were closely apposed by somatostatin-positive terminals in a regional-specific manner. Neuronal somata and dendrites containing either sst2A, sst2B or sst4 were found to exist in close proximity, although not necessarily synaptically linked, to somatostatin-positive terminals. Together, in the central nervous system the effects of somatostatin are mediated by several different receptor proteins which are distributed with considerable regional overlap. However, there appears to be a high degree of specialization among somatostatin receptor subtypes with regard to their subcellular targeting. This subtype-selective targeting may be the underlying principal of organization that allows somatostatinergic modulation of neuronal activity via both pre- and postsynaptic mechanisms.
Animals↗
Distribution of grip force in three different functional prehension patterns.
Normative data of the grip force distribution necessary to complete functional tasks are limited. Small force sensors have been specially designed for accurate measurement of the dynamic handgrip force distribution by attaching them to the palmar surface of the hand. Seventeen healthy participants performed three different tasks, each requiring a different functional prehension pattern. When cylindrical objects were manipulated, the highest average grip forces were found at the fingertips and the thumb, followed by the middle finger. In a spherical grasp pattern, the contributions by the thumb, ring and small fingers always exceeded 71% of the total grip force. The highest local forces of 9.9 N were measured when a zip was closed with a tip pinch. Individual finger forces were found to differ by gender, but not by hand dimension and age. The results are useful for biomechanical modelling of the hand, for designing ergonomic tool grips, and for evaluating hand function.
Adult↗
Chronic osteomyelitis in a new rabbit model.
Dogs, rats, and rabbits are the most suitable species to induce chronic osteomyelitis and to study different methods of treatment. In rabbits, the incidence of and mortality from Staphylococcus aureus-induced osteomyelitis of the tibia depends on the method of prelesions and the amount and virulence of species-specific bacteria used. In this study two different lesions were combined simultaneously in the medullary canal of the femurs by aspiration of bone marrow, leaving the insertion needle in situ. A sclerosing agent was then inoculated followed by 300,000 bacteria of a rabbit-derived S. aureus strain to initiate infection. With this method, the incidence of chronic progressive osteomyelitis of the femur was increased to 100%. A relatively low mortality was observed, probably due to a lower number of inoculated bacteria as compared to other rabbit models described. The incidence of acute to chronic osteomyelitis was diagnosed by local signs, x-rays, microbiological recovery, and gross pathology of the femur. Initial fever, weight loss, abscess formation in soft tissues, and pain on palpation characterize the clinical features in the course of development of this chronic disease.
Animals↗
Repetitive pneumoperitoneum with ozonized oxygen as a preventive in lethal polymicrobial sepsis in rats.
The aim of this study was to test whether repetitive pretreatments of rats with ozonized oxygen at relatively low gas volumes into the abdomen (20 ml per rat per day) have any beneficial or detrimental effects on the course of a polymicrobial-induced lethal peritonitis. Peritonitis was induced in a surgical or a nonsurgical model by usage of fecal material from the cecum. As the biological read out we used the mortality analysis. To include possible mechanisms by which ozone might influence the septic outcome, we characterized the gene expression of the pro-inflammatory cytokines IL-1beta, IL-2, and TNF-alpha mRNA in lymphoid organs. In both models, we found a significant beneficial influence of a dose-dependent O(2)/O(3 )pneumoperitoneum on the survival rate when compared to control animals or to room air. The ozone-enhanced survival seems to be independent from altered cytokine expression because there were no differences noticed in the levels of bacterial-induced gene expression of IL-1beta and TNF-alpha in septic animals pretreated with ozonized oxygen when compared to control animals.
Animals↗
Lymphogenic metastatic spread of auricular VX2 carcinoma in New Zealand white rabbits.
INTRODUCTION: The auricular VX2 carcinoma of the New Zealand white rabbit serves as an animal model for human squamous cell carcinomas of the head and neck region (HNSCC), since both tumors tend to metastasize lymphatically, leading to early lymph node and subsequent distant metastasis. The aim of this study was to examine the pattern of lymphogenic metastatic spread in untreated auricular VX2 carcinomas, since the resulting knowledge potentially could help in the development of new treatment strategies for human HNSCC. MATERIALS AND METHODS: VX2 carcinomas were implanted into both ears of 22 New Zealand white rabbits. The animals were sacrificed at days 7, 14, 21, 28 or 32 after tumor implantation, followed by a detailed histopathological examination of their head and neck lymph nodes. RESULTS: On day 7 after tumor implantation 25% of the animals had metastases in the parotid lymph node, which is the first draining lymph node of the tumor region. This number rose to 87.5% by day 28. At this time 12.5% of all animals also had an additional metastasis in the second echelon node. CONCLUSION: A reproducible metastatic spread into the first draining lymph node could be demonstrated for the auricular VX2 carcinoma of the New Zealand white rabbit. The VX2 carcinoma therefore appears to be a highly suitable animal model for studying the sentinel node concept in the context of human HNSCC.
Animals↗
Expression of MMP-3, MMP-13, TIMP-2 and TIMP-3 in the VX2 carcinoma of the New Zealand white rabbit.
BACKGROUND: Squamous cell carcinomas of the head and neck region (HNSCC) are among the most common malignancies in this area. The VX2 carcinoma of the New Zealand white rabbit metastasizes lymphatically as is the case in HNSCC and therefore, potentially, could be used as a model for HNSCC. Since the family of matrix-metalloproteinases (MMPs) is involved in the process of HNSCC invasion, the aim of this study was to investigate the expression level of MMPs and their specific inhibitors (TIMPs) in the VX2 carcinoma to evaluate if they also play a role in VX2 tumor invasion as observed in human HNSCC. MATERIALS AND METHODS: The VX2 carcinoma was generated by tumor implantation in the rabbit's ear as previously described. Western blots were performed under standard conditions, utilizing antibodies against MMP-3, MMP-13, TIMP-2 and TIMP-3. Immunohistochemical staining was performed with the ABC-complex method. RESULTS: A positive immunohistochemical signal could be detected for MMP-3, TIMP-2 and TIMP-3 with no significant signal for MMP-13. In the Western blots immunoreactive bands could be observed for MMP-3, MMP-13, TIMP-2 and TIMP-3. CONCLUSION: MMP-3, MMP-13, TIMP-2 and TIMP-3 were found to be expressed in VX2 carcinomas of the New Zealand white rabbits. The VX2 carcinoma therefore resembles HNSCC tumors not only in its metastatic behavior, but also regarding the expression of MMPs and TIMPs, which are the probable keyplayers during the event of invasion. These observations further underline the significance of the VX2 carcinoma as a model tumor of human HNSCC.
Animals↗
The auricular VX2 carcinoma--an animal model for sentinel node concept.
BACKGROUND: Considering the increasing clinical significance of the sentinel node (SN) concept, the applicability of the auricular VX2 carcinoma as an animal model for simulation of the SN concept was evaluated. MATERIALS AND METHODS: By means of blue dye and immunofluorescence-marked colloids, the lymphatic drainage of the auricle was described in 8 New Zealand white (NZW) rabbits. In 28 NZW rabbits, the extent of metastatic spread of auricular VX2 carcinomas after 8, 18, 21, 28 and 32 days of tumor growth was examined. RESULTS: Lymphogenic metastatic spread was limited to the parotideal lymph node functioning as SN for 21 days. The disintegration of the physiologic integrity of the SN leads to metastatic spread in the area of the secondary lymph node station after 28 days of tumor growth with successive hematogenic spreading. CONCLUSION: The auricular VX2 carcinoma in NZW rabbits is an appropriate animal model for simulation of the lymphogenic metastatic spread and the SN concept in HNSCC.
Animals↗
Intravenous chemotherapy with cisplatin for regional lymph node metastases of auricular VX2 carcinoma.
INTRODUCTION: The VX2 carcinoma is well established as a useful model for studies on treatment of primary tumors of various locations including the rabbit's auricle; however, limited experience exists on the treatment modalities of lymph node (LN) metastases. In this investigation we studied the frequency and extent of lymphogenic metastatic spread of auricular VX2-carcinomas and their response to systemic chemotherapy. MATERIALS AND METHODS: Induction of a right-sided auricular VX2-carcinoma in 17 healthy New Zealand white rabbits was followed by ablation of the right auricle and intravenous application of 1 mg/kg KG CDDP (cisdiamminedichloroplatinum (II)) dissolved in 2 ml NaCl via the left-sided auricular vein in 10 rabbits (group 1), while 7 rabbits (group 2) remained untreated. After a 24-day follow-up period, animals of both groups were sacrificed and the regional draining LN as well as the lungs were isolated and examined histopathologically. RESULTS: Group 1. Following intravenous cisplatin therapy (ICT), 6/10 animals showed no vital tumor cells within LN metastases of the first draining LN station, while 4/10 animals had necrotic LN metastases limited to the parotideal LN. Group 2. All 7 animals showed necrotic LN metastases of the first and second draining LN station as well as pulmonary metastases. CONCLUSION: The auricular VX2-carcinoma, characterized by frequent lymphogenic metastatic spread and response of LN metastases to ICT, offers an excellent animal model for further studies on the optimised treatment of lymphogenic metastatic spread in HNSCC.
Animals↗