ISSN:0894-1939    

DOI:10.3109/08941938909018260

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Staphylococcus aureus und coagulase-negative staphylococci of species commonly isolated from biomaterial-associated infections commonly express fibronectin-binding surface proteins and the ability to interact with collagen. These findings, us well us the ability of coagulase-negative staphylococci to produce surface slime or capsular material. are presented as alternative models for how biofilms develop on biomaterial surfaces. Further knowledge of how bacteria und eukaryotic cells interact with various biomaterials materials bill stimulate the development of better implant devices to avoid biomaterial-associated infections

ISSN:0894-1939    

DOI:10.3109/08941938909018261

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

The significance of polymer-associated infections caused by coagulase-negative staphylococci is discussed. The aspects of bacterial adhesion to polymeric materials as the first important pathogenetic step in the development of such infections are treated. The role of extracellular slime substance (ESS) produced by the bacteria in the pathogenesis is elucidated und newer results concerning the interference of ESS with host defense mechanisms and antibiotic therapy lire presented. As an approach to the prevention of the prevention materials is infections. the modification of the polymeric materials is introduced. Results of recent studies to achieve materials by radiation modification of polymers as well as the development of antimicrobial surfaces by incorporating or bonding antibiotics to polymers are presented.

ISSN:0894-1939    

DOI:10.3109/08941938909018262

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Bacterial slime produced in muss cultures of the RP 12 strain of Staphylococcus epidermidis was extracted with 4 M guanidine-HCl plus 0.05 M sodium acetate and 0.55% CHAPS, concentrated, dialyzed, und subjected to separation on DEAE sephacel columns. Three fractions, I-2A, I-2B, und I-4, were eluted with linear gradients of NaCl. Fractions I-2A and I-2B were alcian blue positive, whereas I-4 was alcian blue negative but the most electronegative The crude polysaccharide fraction and the three purified fraction were incubated individually for 2.5 or 20 h with normal rabbit alveolar macrophages (AM) to determine their effect on a subsequent PMA-induced oxidative burst. The crude fraction (50–200µg/mL) und I-2B (50–200µg/mL) primed the AM to give approximately a threefold increase in the PMA-induced burst after 2.5 h incubation. In contrast, a 20-h incubation resulted in a 30–40% incubation of the PMA-induced burst Mith AM incubated with the same concentrations of the crude, I-2A, or I-2B fractions. Fraction I-4 had no detectable effect. The fractions also were tested to determine if they could elicit an oxidative burst in BCG-immune AM. None of the fractions (up to 500µg/mL) elicited a significant oxidative burst even though BCG-immune. AM yielded a PMA-induced burst 100 times that observed with normal resident AM. These data suggest that slime from S. epidermidis can impair the PMA-induced oxidative burst of normal AM during a 20-h incubation period and could explain in part why host defenses are compromised by slime-producing S. epidermidis

ISSN:0894-1939    

DOI:10.3109/08941938909018263

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Modern medicine would be unthinkable without the use of a bewildering array of foreign devices. Intravascular catheters and monitoring devices, artificial joints, prosthetic heart valves, and many other prosthetic devices have become essential elements of the medical armamentarium.

ISSN:0894-1939    

DOI:10.3109/08941938909018264

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Recent data suggest that fibronectin may favor Staphylococcus aureus infection by promoting attachment to either injured tissues or implanted foreign bodies. Using a previously described in vitro assay, we show that promotion of S. aureus adherence by surface-bound fibronectin, adsorbed on polymethylmethacrylate PMMA coverslips, is antagonized by antistaphylococcal antibodies present in immunoglobulin G (IgC) purified from human plasma. Among the different organisms tested, the protein A-deficient strain Wood 46 of S. aureus was the most strongly inhibited by purified IgC or whole serum dose-dependently. Bacterial adherence was not influenced by preincubating fibronectin-coated PMMA with either purified IgC or whole serum. However, inhibition of bacterial adherence was directly related to the extent of IgG binding to S. aureus Wood 46. When F(ab')2fragments of purified IgC were tested in the adherence assay, they could also reduce the interaction between S. aureus Wood 46 and fibronectin-coated PMMA. Two other staphylococcal strains were also tested in the adherence inhibition assay: Whereas the protein A-rich strain Cowan I of S. aureus was moderately inhibited by purified IgG or whole serum, S. epidermidis KH 11 was not at all inhibited by IgG which hind poorly to the bacterial cells. This study has demonstrated that bacterial coating by humoral factors, and specifically IgC, may influence significantly subsequent adherence of S. aureus to surface-bound fibronectin.

ISSN:0894-1939    

DOI:10.3109/08941938909018265

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

We summarize indications, contraindications, and therapeutic guidelines for the use of adjunctive hyperbaric oxygen therapy (HBO) in problem wounds and selected orthopaedic injections. Three typical cases that all were, successfully treated with HBO are presented: a chronic osteomyelitis which was a sequela to an open tibia fracture, a second- and third-degree burn injury of the entire lower extremity, and a case of chronic osteomyelitis in (in insulin-dependent diabetic

ISSN:0894-1939    

DOI:10.3109/08941938909018266

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Copovithane (CPV), a synthetic polymer, has been shown to have antitumor activity and also to reduce mortality in experimental murine peritonitis. The purpose of this study was to compare CPV with muramyl dipeptide (MDP), (in immunomodulator of proven efficacy in simulated surgical infection. Six groups of CBA/J mice were compared; they received intramuscular injections of normal saline (controls), MDP (100µg), or CPV (100, 200, and 400 mg/kg) 24 h prior to bacterial challenge. The challenge consisted of a Klebsiella-impregnated thigh suture. The first experiment assessed survival after bacterial challenge. The MDP and the CPV groups both had median survival times of 3 days, significantly longer than the control group (1 day, p<.05). In the second experiment, animals were sacrificed at 6, 24, and 48 h following bacterial challenge, and blood and infected muscle were taken for quantitative bacteriology. At 6 h, there was no difference between groups. Both the MDP rind CPV groups had significantly (p<. 05) lower blood bacterial counts than the control group at 24 and 48 h. Both the MDP and CVP groups had significantly lower local bacterial recovery than controls at 48 h (p<. 05), and local bacterial recovery of the MDP group was significantly lower than the control group at 24 h (p<.05). CPV improved survival and reduced local and systemic bacterial recovery compared with controls. Although the effect of CPV was similar to MDP in this model, it consistently was of lower magnitude and had a narrow dose range.

ISSN:0894-1939    

DOI:10.3109/08941938909018267

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Heparin potentiation of clot lysis by streptokinase was studied in a rabbit model. Clot was initiated in the rabbit aorta with stasis and thrombin and allowed to naturally propagate proximally until stasis met flow. The clot was allowed to age for 1 h before assigning treatment. Fifteen rabbits (group I) were given streptokinase (10,000 IU/h) and 11 rabbits (group II) were given streptokinase (10,000 IU/h) plus sodium-heparin (120 IU/h). Thrombolytic therapy was continued for 5 h. Clot lysis averaged 30% in group I and 70% in group II. Ten of 11 rabbits in group II had more than 50% clot lysis, whereas only 4 of 15 in group I had this degree of lysis. One group II rabbit and four group I rabbits died prematurely; each was noted to have clot propagation at the time of death. While a trend for amelioration of hypofibrinogenemia was observed in the group receiving both streptokinase and heparin, this difference was not statistically significant. We conclude, in the animal model, that thrombolysis by a combination of heparin und streptokinase is more effective than streptokinase alone. Systemic effects are apparently no worse with the combination.

ISSN:0894-1939    

DOI:10.3109/08941938909018268

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

The mechanism of induction of the migrating motor complex (MMC) by neural or humoral agents and their role in the control of fasting motility are not well understood. Our aim was to determine the role of extrinsic und intrinsic nerves in mediating the induction of the MMC by motilin. Three groups of dogs were studied. Group I consisted of neurally intact control dogs. In group II, intrinsic neural continuity between the duodenum and the jejunum was interrupted by transection and reanastomosis of the distal duodenum. Dogs in group III underwent disruption of all intrinsic andextrinsic neural input to the entire jejunoileum. Serosal electrodes were sewn to duodenum and jejunum in all dogs. After a 2-week recovery, fasting myoelectric activity was recorded on four or more occasions. Motilin (0.1µg/kg iv) was given 30 min after a spontaneous duodenal phase III. In group I (controls), motilin induced a premature MMC, which originated in the duodenum and migrated along the small intestine. In group II (intrinsic neural disruption), motilin induced a premature MMC, which began simultaneously in the proximal duodenum and proximal jejunum. In group III (intrinsic and extrinsic neural disruption), motilin induced a premature MMC in the duodenum but not in the jejunum: rather, a short, nonmigrating burst of spike potentials occurred simultaneously in all jejunal electrodes. These observations suggest that extrinsic innervation is necessary for motilin to induce phase III activity in the jejunum. Extrinsic neural pathways appear to mediate motilin-induced MMC activity in the jejunum.

ISSN:0894-1939    

DOI:10.3109/08941938909018269

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor