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L Steinstraesser

Publications and source records attributed to L Steinstraesser.

11 recordsLinked to original sources
PubMed2004

The impact of topical antiseptics on skin microcirculation.

AIM: Antiseptics are commonly used in clinical practice to disinfect tissue and to avoid infections. However, topical antiseptics are assumed to have an influence on skin microcirculation, per se. Thus, the aim of the study was to analyse the influence of topically applied antiseptics on the microcirculation of intact skin in vivo. MATERIALS AND METHODS: The investigation was carried out on ears of male hairless mice (SKH-1hr, n = 25). The influence of four antiseptics was examined. Sodium chloride 0.9% served as control. An alcohol-based solution with a mixture of ethanol, 2-propanol and purified water (Softasept), an antiseptic with octenidine dihydrochloride and phenoxyethanol as the main active agents (Octenisept), as well as hexamethylenbiguanide (Lavasept) and 70% ethanol were tested. Intravital fluorescence microscopy in combination with intravenous injection of the fluorescence dyes FITC-Dextran as plasma marker and Rhodamine 6G (leukocyte staining) allowed a quantitative analysis of standard microcirculatory parameters (vessel diameter, functional capillary density, red blood cell velocity, FITC-leakage and leukocyte endothelium interaction). Recordings of the microcirculation in several regions of interest (ROI) were made prior to application and after 10 min exposure time and 60 min after the baseline data. Data were evaluated off-line with aid of computer assisted analysis. RESULTS: The diameter of arterioles decreased after the treatment with the alcoholic solutions. The other two antiseptics (Octenisept and Lavasept) caused a significant increase. Functional capillary density (FCD) was significantly reduced after application of ethanol and Softasept. There was no reduction of FCD following application of Octenisept. After treatment with ethanol and Softasept there was a significant decrease in red blood cell velocity (RBCV). The use of Lavasept revealed a decrease of FCD and RBCV. In the Octenisept treated group RBCV shows a mild increase after 10 minutes. The application of ethanol, Softasept and Lavasept was characterized by a significant increase of leukocyte endothelium interaction (LEI). After treatment with saline and Octenisept LEI remained constant. All used antiseptics except of Octenisept caused a significant leakage of FITC-Dextran. CONCLUSION: The antiseptics used in this study all showed an influence on skin microcirculation. As expected, our findings show that the alcoholic solutions are most aggressive to skin microcirculation.

Administration, Topical↗
PubMed2004

Host defense peptides in burns.

Overuse of antibiotics and failure to apply basic infection control policies and procedures have contributed to the increasing multi-drug resistance of many nosocomial pathogens. The alarming increase of multi-drug-resistant bacteria (e.g. Pseudomonas aeruginosa, methicilin-resistant Staphylococci, vancomycin-resistant Enterococci) causes infected wounds associated with high mortality and morbidity in burned patients and focuses attention on the need for better treatment and prevention of wound infections. The review points out and discusses some emerging alternatives to antibiotics used in clinical practice, with special emphasis on the role of the innate immune response and potential application of human host defense peptides in thermal injury.

Antimicrobial Cationic Peptides↗
PubMed2004

[Gorham-Stout disease: report of a case affecting the right hand with a follow-up of 24 years].

Gorham-Stout disease is a rare idiopathic syndrome with distinctive clinical, pathologic and radiologic features. It is a variant form of osseus angiomatosis associated with massive osteolysis of bone. Usually appearing after trauma, the disease is described to occur at any age. Especially in case of thoracic involvement (chylothorax), lethal outcomes are reported. In Medline, about 200 cases have been described. A patient with osteolysis of the right hand following contusion at the age of two years is reported. Despite radiotherapy and repeated bone grafting, the osteolysis progressed until today (24 years). The pathologic features and various treatment methods for hand involvement are discussed.

Adult↗
PubMed2003

[No problem with liposuction?].

Subcutaneous liposuction in tumescent technique is the most frequent aesthetic plastic procedure in the United States. In Germany, nearly 250,000 liposuctions are done per year by a variety of surgical and nonsurgical specialists including plastic surgeons, dermatologists, gynecologists, oral surgeons, and otolaryngologists in settings ranging from hospital operating rooms to physicians' offices. The method is applied and promoted as an easy-to-learn technique that is suited as an outpatient procedure. Although major complications seem to be rare, there are definite risks, including death at a rate of 1/5,000 procedures. Major risk factors are insufficient hygiene standards, multiliter wetting solution infiltration, megavolume aspiration, multiple cosmetic procedures in one setting, sedative and anesthetic drug hangover threatening ventilation, permissive postoperative discharge, and mistakes in patient selection. When major complications occur, office-based practitioners may refer patients to hospital emergency departments, where medical personnel unfamiliar with this procedure may underestimate the risk of major complications.

Adult↗
PubMed2002

[Intravital microscopic analysis of perfusion, leukocyte-endothelial cell interaction and neovascularization after burns: an in vivo study of SKH-1/hr hairless mice]].

Breakdown of skin microcirculation is supposed to play a key role in pathophysiology of burn injury. The aim of the study was to develop a burn model, which allows repetitive quantitative in vivo analysis of microcirculation after burn injury with special focus on leukocyte endothelium interaction over a longer period of time. Male hairless mice (SKH-1/hr) were used. Deep partial thickness burns were inflicted in no-touch-technique to the ears. Intravital fluorescent microscopy in combination with FITC-dextran as a plasma-marker was used to assess standard microcirculatory parameters. Leukocytes were stained with rhodamine-6-G to study their interaction with the endothelium.

Animals↗
PubMed2001

Protegrin-1 enhances bacterial killing in thermally injured skin.

OBJECTIVE: Septic complications and the emergence of drug-resistant microbes represent serious risks to patients. Recently, naturally occurring peptides have been discovered that possess potent and broad-spectrum antimicrobial activity. Protegrin-1 is particularly attractive for clinical use in human wounds because, unlike defensins, protegrin-1 retains broad antimicrobial and antifungal activity at physiologic salt concentration and in the presence of serum. The objective of this study was to examine the efficacy of protegrin-1 in killing multiple drug-resistant microbes isolated from human burn patients. DESIGN: For thein vitroexperiment, bilayer radial diffusion was performed comparing standard antibiotics with protegrin-1 on multiple-drug-resistant microbial organisms isolated from infected burn wounds. In vivo, rats received a 20% total body surface area partial-thickness burn by immersion in 60 degrees C water for 20 secs followed by wound seeding with 106 colony forming units of Silvadene-resistant Pseudomonas aeruginosa. SETTING: University of Michigan research laboratory. SUBJECTS: Adult, male Sprague-Dawley rats. INTERVENTIONS: Rats were randomized into three groups: those receiving synthetic protegrin-1, acetic acid (carrier), or gentamicin (positive control). Protegrin-1 was administered by topical application or intradermal injection. Wound tissues were harvested aseptically at different time points for quantitative bacterial counts. MEASUREMENTS AND MAIN RESULTS: In vivo and in vitro experiments revealed rapid and significant decreases in bacterial counts for protegrin-1-treated groups compared with controls. CONCLUSIONS: This study shows that protegrin-1 potentially may be used as an alternative or adjunct therapy to standard agents used to treat wound infections.

Administration, Topical↗
PubMed2001

Feasibility of biolistic gene therapy in burns.

Skin is an especially attractive target for genetic manipulation because it is readily accessible and easily monitored for both the presence and the expression of inserted genes. This study was designed to assess the feasibility of particle mediated gene transfer to burned skin and to compare the transfection efficiency, anatomic distribution, and duration of transgene expression achievable in normal versus burned skin. Two days following scald injury of varying depths in 60 degrees C water (10 s: superficial partial; 20 s: deep partial; 40 s: full thickness) reporter gene (beta-galactosidase) constructs were delivered using a gene gun at various helium pressures (200-600 psi) to normal and burned skin. A time course study was performed to examine the kinetics of transgene expression. Animals received a superficial partial thickness burn and were sacrificed 12 h, 1, 3, 5, 7, 14, or 21 days after gene transfer. India Ink injection and immunohistochemistry were used to assess the depth of the scald injury. Transfection efficiency was measured in skin homogenates 24 h after gene transfer by morphometric and chemoluminescent assays. We found that the extent of tissue damage was directly related to the duration of heat source exposure. Reporter gene activity was significantly higher in superficial partial thickness burns compared to normal controls and gradually declined with increasing tissue injury. No activity was seen in the full thickness burn group. Beta-galactosidase activity reached a maximum level 12 h after gene transfer in both normal and superficial partial thickness burned skin with no levels seen after 5 days post-transfection. These findings indicate that particle-mediated gene transfer in thermally injured skin is feasible and may provide a means of introducing biologic agents into injured tissue capable of enhancing bacterial clearance and improving wound healing.

Animals↗
PubMed2000

Lipopolysaccharide-binding protein accelerates and augments Escherichia coli phagocytosis by alveolar macrophages.

BACKGROUND: The first step in bacterial clearance by leukocytes is attachment and phagocytosis. Although lipopolysaccharide-binding protein (LBP) is best known for potentiating LPS-induced cytokine production through a CD14-dependent pathway, recent studies suggest that LBP plays a critical role in clearance of gram-negative bacteria and is essential for survival after bacterial challenge. We therefore sought to examine LBP's effect on Escherichia coli phagocytosis by alveolar macrophages (AMs) and to determine if this effect is mediated through CD14. MATERIALS AND METHODS: Phosphatidylinositol-specific phospholipase C (PIPLC)-treated and untreated rat AMs were incubated in the presence of increasing doses of recombinant LBP or negative control protein (choramphenicol acetyltransferase) prior to E. coli-FITC (Ec-F) BioParticle challenge. Phagocytosed bacteria were assayed by fluorescence measurement. A time course study was also performed. RESULTS: LBP potentiated phagocytosis of Ec-F BioParticles by AMs in a dose-dependent fashion. Kinetic studies showed that LBP augmented Ec-F phagocytosis by 76% at 30 min. Treatment of AMs with PIPLC to remove CD14 resulted in only a partial decrease in LBP-mediated enhancement of phagocytosis. CONCLUSION: These results clearly demonstrate that LBP plays an important role in enhancing Ec-F binding and phagocytosis in a time- and dose-dependent manner. This observed increase may not require the presence of CD14 as significant potentiation of phagocytosis still occurred after PIPLC treatment. We postulate that the LBP-mediated increase in Ec-F phagocytosis can occur in the absence of CD14 through the presence of another receptor.

Acute-Phase Proteins↗
PubMed2000

Kupffer cell activation by lipopolysaccharide in rats: role for lipopolysaccharide binding protein and toll-like receptor 4.

Lipopolysaccharide (LPS) binding protein (LBP) is a key serum factor that mediates LPS activation of mononuclear cells. In the presence of LBP, 1/1,000 the concentration of LPS is sufficient to activate peripheral blood monocytes. Previous studies with Kupffer cells have shown a variable effect of serum on LPS activation of these cells and led to the conclusion that, unlike extrahepatic mononuclear cells, Kupffer cells do not respond to LPS in an LBP-dependent fashion. Because there are multiple components in serum other than LBP that might affect LPS activation, these reports with serum are difficult to interpret. To investigate the specific role of LBP in LPS activation of Kupffer cells, we produced a functional recombinant rat LBP using a baculovirus expression system, which we used to selectively examine the role of LBP's on Kupffer-cell function. Isolated Kupffer cells exposed to increasing concentrations of LPS (0, 1, 10 ng/mL) showed a dose-dependent increase in TNF-alpha production, which was augmented and accelerated by the presence of LBP. The effects of LBP on Kupffer cell activation by LPS are dependent on a functional Toll-like receptor 4 (Tlr 4) because Kupffer cells from C3H/HeJ mice failed to respond to LPS in the presence of LBP. LBP plays an important role in mediating Kupffer cell activation by LPS, and these effects are dependent on the presence of functioning Tlr 4.

Acute-Phase Proteins↗
PubMedDate not supplied

Skin lipopolysaccharide-binding protein and IL-1beta production after thermal injury.

In response to a burn injury, skin can have an inflammatory response characterized by the production of inflammatory cytokines, recruitment of immune cells, containment of invading organisms, and clearance of noxious substances from the wound. Lipopolysaccharide-binding protein (LBP) is a molecule that is capable of coordinating all 4 functions; we previously found evidence that suggested that LBP is produced within surgical wounds. Because of the central role of LBP in the response to bacterial infection, as well as in the high rate of infection after burn injuries, we sought to determine whether a thermal injury could affect wound LBP production and thereby affect host responses against bacterial infection. Rats were given either a burn or a sham burn and were killed 24, 48, and 72 hours after the injuries. Wound specimens were assayed for bacterial counts and for the presence of LBP, messenger (m)RNA, and interleukin (IL)-1beta mRNA. Wound LBP mRNA was significantly upregulated at 24 hours in the group with burn injuries (P < .05; burn vs sham burn); this was followed by decreases at 48 and 72 hours. Immunohistochemistry showed LBP protein in the epidermis of animals with burns. Bacterial counts increased in the group with burn injuries (P < .05; burn vs sham burn) and continued to rise for 72 hours. IL-1beta mRNA levels were elevated at all time points in the group with burn injuries (P < .05). These results suggest an inverse correlation between burn wound LBP expression and bacterial wound counts. This failure to maintain local LBP production after severe thermal injury despite localized inflammation shown by high IL-1beta levels may predispose local wounds to bacterial invasion.

Acute-Phase Proteins↗