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Background: Thermal mud is a therapeutic agent widely used in the treatment of painful arthritic processes. The mechanism by which mud therapy works is still not well known. Its effect continues for months after completion of treatment. In order to verify whether thermal mud treatment brings about changes in the production of hormone peptides from proopiomelanocortin, the levels of plasma beta-endorphin and some hormones of the pituitary-adrenal glands (ACTH and cortisol) were determined in patients affected by osteoarthritis undergoing thermal mud therapy., Methods: The levels of plasma beta-endorphin and some hormones of the pituitary-adrenal glands (ACTH and cortisol) were assessed by radiometric methods in seventeen males affected by osteoarthritis. The patients underwent a cycle of twelve sessions of thermal mud therapy. The tests were carried out immediately before thermal treatment, immediately after the first session, twelve days after the start of treatment, and again one month after completion of the treatment., Results: beta-endorphin levels decreased significantly twelve days after the start of treatment. The level was still lower, although not significantly, even thirty days after completion of the treatment. Plasma ACTH also decreased during treatment. The decrease of this hormone was progressive and persisted after completion of treatment. Significant variations compared to baseline were found only thirty days after completion of treatment. Plasma cortisol decreased significantly after only one session of mud therapy. This hormone did not decrease any further during treatment, however, after twelve days it was still significantly lower than baseline. After completion of treatment, cortisol slightly increased, but thirty days later it was still lower, although not significantly, than baseline., Conclusions: It may be suggested that thermal treatment, by reducing inflammation, reduced pain and therefore diminished the cause of stress.

Background: In order to investigate platelet activation after contact with artificial materials, which is an important aspect of biocompatibility especially for the blood-contacting devices, platelet morphological modifications and spread area were evaluated by light microscopy and image analysis after contact with glow discharge-treated polybutylene terephthalate coated with a polymer for platelet concentrate filtration., Methods: A hydrophilic polymer made of partially hydrolyzed polyvinyl-acetate containing polyethylene oxide/poly-propylene oxide copolymer block as lateral chains (PVA) (Biofil S.r.l., Cavezzo, Modena, Italy) was evaluated. After contact with PVA, platelets were allowed to settle on a siliconized slide and then fixed and stained. The specimens were analyzed by image analysis. The percentages of spreading, round and dendritic shapes, as well as the presence of aggregates, were evaluated, and the mean area of the spread platelets was measured., Results: PVA induced significant variations neither in the percentages of shape change distribution, nor of the mean spread area. However it determined a statistically significant reduction in platelets with the area from 60 to 70 mu 2. Such minimal variations agree with the results we obtained in the past, namely a non significant platelet adhesion induced by the same material., Conclusions: The method confirms the results of platelet adhesion and release reaction (the study of release reaction needs more refined but more expensive methods). However, the study of morphological modifications by image analysis is not suitable for testing materials that induce massive platelet adhesion, because the number of the residual platelets could be too low for the microscopic evaluation.

Background: The aim of the study was the assessment of the influence of cytokines on bone ageing by measuring their level in serum and their secretion in vitro by monocytes from women of different age., Methods: The levels of cytokines in 34 postmenopausal subjects and 14 old subjects were compared to those measured in 13 cycling subjects who were considered as control group. Subjects suffering from diseases inducing secondary osteoporosis, subjects taking medications that affect bone metabolism and alcohol- or tobacco-consumers were excluded from the study. The levels in serum of (i) the bone stimulating peptide insulin-like growth factor-I (IGF-I), (ii) the inhibitor of bone resorption interferon-gamma (IFN gamma), (iii) the stimulators of bone resorption interleukin-1 beta (IL-1 beta) tumor necrosis factor alpha (TNF alpha) and interleukin 6 (IL-6) were evaluated by immunoassay. IL-1 beta, TNF alpha and IL-6 secreted by monocytes (MO) cultured in vitro from peripheral blood of the same subjects were measured, too. Bacterial endotoxin (LPS) was used as stimulator for cytokine secretion by monocytes., Results: Unlike IFN gamma, which was unaltered, circulating IGF-I level was found significantly diminished in postmenopausal and old subjects compared to control group. Among stimulators of bone resorption, IL-6 was greatly increased in postmenopausal and old subjects, while TNF alpha was reduced in postmenopausal group. In the supernatants of unstimulated monocytes the level of IL-1 beta was consistently decreased in old subjects; TNF alpha was found to be decreased in postmenopausal and old subjects. The stimulation index (SI), calculated as the ratio between the level of cytokines secreted by LPS-stimulated MO and the level of cytokines secreted by unstimulated MO, was found to be significantly increased for IL-1 beta and TNF alpha in postmenopausal subjects vs control group. In the old subjects the SI for IL-6 was enhanced., Conclusions: The data collected suggest that the measurement of cytokines in serum and supernatants from monocytes may give a picture of the mechanisms regulating bone aging.

Background: The aim of the research was the evaluation of plasmatic protein adsorption on untreated polybutylene terephthalate, corona treated polybutylene terephthalate and polyvinylacetate coated corona treated polybutylene terephthalate., Methods: Total proteins, albumin, immunoglobulins, fibrinogen, insulin and ostecalcin were determined on plasma after contact with these polymers., Results: Unsignificant variations were observed for the assayed proteins., Conclusions: The conclusions are drawn that the tested materials do not adsorbe significantly the most important plasmatic proteins.

The aim of this study was to evaluate endothelin-1 and prostacyclin production by human endothelial cells cultured in the presence of polyethylene terephthalate and collagen-coated PET. Cell counting and the assay of endothelin-1 and 6-keto-prostaglandin F1 alpha, stable metabolite of prostacyclin, were carried out after 48 hour contact of the cells with the examined materials. Endothelial cell contact with uncoated PET caused a significant reduction in cell number, a significant increase in the production of endothelin-1 and a not significant increase in 6-keto-prostaglandin F1 alpha. The endothelial cell contact with collagen-coated PET caused a highly significant decrease in cell number and a not significant decrease in endothelin-1 and 6-keto-prostaglandin F1 alpha. It was concluded that PET causes both a decrease in cell number and a remarkable increase in endothelin-1. On the contrary, collagen-coated PET determines a decrease in cell number and a slight reduction of endothelin-1 and 6-keto-prostaglandin F1 alpha.

The aim of this study is the evaluation of the in vitro tissue factor production by endothelial cells cultured in the presence of Woven or Knitted Dacron. The spectrophotometric evaluation of the protein content of the cultures and the both indirect assay and enzyme immune assay of tissue factor in cellular lysates were carried out after 72 hour contact between the cells and the materials under examination. The endothelial cell contact with Knitted Dacron did not determine variation in protein content, but it induced a significant increase in tissue factor production. The endothelial cell contact with Woven Dacron determined no significant variations neither in the protein content nor in the tissue factor concentration. It is concluded that Knitted Dacron, through the induction of tissue factor synthesis, can favour the extrinsic pathway of coagulation and therefore the production of thrombi. Woven Dacron, not inducing tissue factor formation, does not activate the extrinsic pathway of coagulation, as for the mechanism considered.

Several issues concerning the biocompatibility) testing of medical devices as stated in European directive 90/385 and 93/42 are discussed. The authors describe the fundamental characteristics that biomaterials should have to be employed in the human body, the assays useful for testing different aspects of biocompatibility and the harmonized regulations already available or under development. The testing protocol applied by the a. in their Lab covering many issues of biocompatibility is presented: a body of experience was gained over the years and it has been revised under the new regulatory items. In conclusion, the biocompatibility of devices must be assessed following the European harmonized standards, the available. Where proper standards are still lacking, feasible testing methods, even if not officially adopted yet, have to be used.

The authors have quantitatively evaluated and compared in vitro the Staphylococcus aureus and Staphylococcus epidermidis strain adhesiveness on various types of silicone used in surgery. The results show that there are some adhesiveness differences between the two assayed strains (S. epidermidis adhesiveness > S. aureus adhesiveness) and among silicone types (adhesiveness on soft silicones > adhesiveness on hard silicones). However all silicones are suitable substrata for in vitro bacterial adhesion.

The authors have examined the alterations in the coagulation pathway of plasma filtered through a polyester filter coated by a hydrophilic polymer. The activation of the coagulation pathway was evaluated by measuring prothrombin time, activated partial thromboplastin time, coagulation factors and fibrinopeptide A. The results obtained demonstrate that the examined filter does not induce significative activation of the coagulation pathway.

The Authors, after a short description of the phenomena following the interaction between blood and biomaterials, take into consideration the different methods used in studying the in vitro, in vivo and ex vivo hemocompatibility, as well as the problems involved by each method and its contribution to the knowledge of hemocompatibility. The Authors report their experience on the in vitro study of the effects induced by some biomaterials on platelets and coagulation factors.

Different factors involved in nosocomial infection and high risk hospital departments are examined. Methods of surveillance of infection in patients, in staff, and monitoring of environment and equipment are settled. The results obtained in environment monitoring and in some kinds of surgical operation are reported. A policy of epidemiological surveillance is proposed.