K. Gerhard Brand

Foreign body tumorigenesis.

This review deals with factors and mechanisms involved in sarcoma development upon implantation of chemically inert foreign bodies. The topic is of importance regarding cancer in asbestosis or schistosomiasis, and also in view of increasing ise of artificial implants. After detailing morphological and biological characteristics of foreign body-induced sarcomas in man and animals, the review focuses on specific properties of implants and experimental animals which determine or influence tumor incidence and latency. Included are surface properties, size and shape of implants, and species characteristics, sex, and genetic background of animals. It follows a description of recent etiologic research which has evealed foreign body tumorigenesis as a multistage developmental process. Some of the salient features are monoclonal forigin from mesenchymal stem cells of the micro-vasculature; origination of neoplastic destination and specific tumor leterminants in cells distant from the implant during the earliest st...

Foreign Body Induced Sarcomas

Several reviews on foreign body (FB) induced tumors have been published in recent years, notably those of Bischoff and Bryson (1964), who proposed the term “solid state carcinogenesis,” Bryson and Bischoff (1969), Ott (1970), and Bischoff (1972). The reader is referred to these monographs, which, taken together, provide a complete bibliography on this subject up to early 1972. There are some differences in the selection of references since the reviewers concentrated on diverse aspects of FB tumorigenesis such as histopathology, chemical and physical properties of implant materials, biocompatibility, methodology of safety testing, or historical accounts. Most of the references listed there have been omitted from the reference section of this chapter because it was not intended to create an updated all-encompassing version of earlier reviews. Instead, the emphasis is on etiological aspects, in accordance with the general orientation of this volume. By elaboration of this perspective, the scope of preceding reviews is extended and a new spectrum of relevant literature is drawn into the discussion.

Do Implanted Medical Devices Cause Cancer

he title of this article poses a question that has been on the minds ~ Tof physicians, patients, and implant manufacturers for decades since surgeons first began using foreign materials for tissue and bone repair. The degree of concern has fluctuated over the years in response to research findings or epidemiological statistics, but is also determined by the risk/benefit ratio of a given procedure. Understandably, risks are more willingly accepted in life-saving or rehabilitating situations, and concerns about remotely possible neoplasms in the distant future cannot weigh too heavily. The attitude is quite different if the risk/benefit ratio of a purely cosmetic operation is to be assessed. The literature on the question before us and its ramifications is voluminous. It has been reviewed repeatedly in the past [1-13]. The reader who desires to consult original sources will find references in these articles and monographs.

Malignant transformation and maturation in non-dividing cells during polymer tumorigenesis.

Summary It was confirmed that, during polymer solid surface carcinogenesis, pre-malignant cells reside on the plastic insert as early as eight months before tumor maturation. No premalignant cells were demonstrated in the surrounding tissue except for the very late stage of less than four weeks. During the premalignant period no mitotic activity or cellular turnover was observed among the cell population that presumably included the premalignant clone. Clearance of carbon particles was minimal. It was concluded that at least in this instance the entire process of premalignant development and maturation seems to take place in non-dividing cells.

Fibronectin in Foreign Body-Induced Sarcomas and Preneoplastic Cells

Abstract Foreign body (FB)-induced murine sarcoma cells and advanced preneoplastic cells as well as normal fibroblasts produce fibronectin (FN) in primary culture; cells at early preneoplasia do not. Hence, the neoplastic properties of FB-induced sarcomas do not depend on absence of FN. Temporary FN repression during early preneoplasia is associated with certain phenotypic cell characteristics.

Cytotoxicity and Cell Cycle Studied with a Combined Tetrazolium-Feulgen Reaction.

Summary On asynchronous and synchronized cultures of Changs conjunctiva cells it was shown that cytotoxic antibodies (in the presence of complement) were most effective during the stage of cytoplasmic cell division, i.e., between mitosis and G1-phase. All other stages of the cellular life cycle were relatively resistant in that longer incubation periods were required for cell destruction. A newly developed combined tetrazolium-Feulgen reaction was used in these studies with advantage.

Suppression of bacterial growth and ammonia formation by citrate buffer in urine collected in ileal loop receptacles.

Bacterial growth in urine collected in ileal loop receptacles is greatly suppressed by the presence of 5 to 10 ml. 1-M. citrate buffer, pH 4. The suppression of bacterial growth by the citrate buffer prevents the formation of ammonia and perhaps other noxious metabolites whic are believed responsible for the irritation and inflammation of the skin exposed to infected urine. The citrate buffer is placed in the ileal loop receptacle at the beginning of each urine collection period.

Antigenic Analysis of Cells and Tissues Common Antigens on Human Erythrocytes and in Cultured Cells.

Summary Antisera were available which had been prepared in guinea pigs and other animal species against established human cell strains such as HeLa, etc. By means of agar-immunodiffusion tests numerous cellular antigens had been denned. Individual sera had been analyzed regarding the antibody specificities they contained. In the present study, selected reference sera were absorbed with pooled human erythrocytes and then subjected to immunodiffusion tests against cell antigen extracts of known composition. Disappearance or significant weakening of specific precipitation lines indicated successful absorption of a specific antibody and, hence, the presence of the corresponding antigen on the erythrocyte membrane. This was established for 8 out of 15 specific cellular antigens investigated. An attempt to correlate precipitating and species-specifically hemagglutinating antibodies was in part satisfactory. It was emphasized in the discussion that pre-cipitable cellular antigens exist in soluble form whereas the corresponding antigens on the erythrocyte membrane are structurally bound.SummaryAntisera were available which had been prepared in guinea pigs and other animal species against established human cell strains such as HeLa, etc. By means of agar-immunodiffusion tests numerous cellular antigens had been denned. Individual sera had been analyzed regarding the antibody specificities they contained. In the present study, selected reference sera were absorbed with pooled human erythrocytes and then subjected to immunodiffusion tests against cell antigen extracts of known composition. Disappearance or significant weakening of specific precipitation lines indicated successful absorption of a specific antibody and, hence, the presence of the corresponding antigen on the erythrocyte membrane. This was established for 8 out of 15 specific cellular antigens investigated. An attempt to correlate precipitating and species-specifically hemagglutinating antibodies was in part satisfactory. It was emphasized in the discussion that pre-cipitable cellular antigens exist in soluble form whereas the...