Objective— To evaluate the in vitro efficacy of polyhexamethylene biguanide (PHMB)‐impregnated gauze dressing in limiting the growth of bacteria both within and underneath the dressing.
Study Design— ...In vitro study.
Methods— Squares of PHMB‐impregnated and control gauze were placed on agar plates inoculated with 1 of 11 bacterial species, including 8 multi‐resistant organisms. Growth under the gauze was assessed qualitatively after 24‐hour incubation. Repeated use of sponges was used to evaluate residual inhibitory activity against Micrococcus lutea and Staphylococcus schleiferi ss. schleiferi. In a second procedure, PHMB‐impregnated and control gauze squares were placed in sterile plastic wells and inoculated with 1 of 5 bacterial species, including Pseudomonas spp. and Klebsiella spp. Inhibition of bacterial growth within and underneath the dressing after 24‐hour incubation was evaluated by quantifying the numbers of bacteria on the well floor and within each square.
Results— PHMB‐impregnated gauze provided greater inhibition of growth of 4/4 Gram‐positive species and 2/6 Gram‐negative species on inoculated plates compared with control gauze. Residual inhibitory activity of PHMB‐impregnated gauze was significantly greater against M. lutea on all days and against S. schleiferi ss. schleiferi on days 1 and 4 compared with control. No bacteria were recovered from inoculated PHMB‐impregnated gauze squares placed in sterile wells or from the well floor underneath. More than 9 × 105 colony‐forming units (CFU) were recovered from inoculated control samples placed in sterile wells and more than 8.4 × 104 CFU were recovered from control well floors.
Conclusion— PHMB‐impregnated gauze dressing, when placed on inoculated agar plates, reduces growth of underlying bacteria, particularly Gram‐positive species. Wet‐inoculated PHMB‐impregnated dressing prevents growth of Gram‐positive and Gram‐negative bacteria both within and underneath the dressing.
Clinical Relevance— PHMB‐impregnated dressings may be useful for reducing contamination of underlying wounds by bacterial pathogens.
Ondansetron, a serotonin-3 receptor antagonist, reduces postoperative shivering. Drugs that reduce shivering usually impair central thermoregulatory control, and may thus be useful for preventing ...shivering during induction of therapeutic hypothermia. We determined, therefore, whether ondansetron reduces the major autonomic thermoregulatory response thresholds (triggering core temperatures) in humans.
Control (placebo) and ondansetron infusions at the target plasma concentration of 250 ng ml−1 were studied in healthy volunteers on two different days. Each day, skin and core temperatures were increased to provoke sweating; then reduced to elicit peripheral vasoconstriction and shivering. We determined the core-temperature sweating, vasoconstriction and shivering thresholds after compensating for changes in mean-skin temperature. Data were analysed using t-tests and presented as means (sds); P<0.05 was taken as significant.
Ondensetron plasma concentrations were 278 (57), 234 (55) and 243 (58) ng ml−1 at the sweating, vasoconstriction and shivering thresholds, respectively; these corresponded to ≈50 mg of ondansetron which is approximately 10 times the dose used for postoperative nausea and vomiting. Ondansetron did not change the sweating (control 37.4 (0.4)°C, ondansetron 37.6 (0.3)°C, P=0.16), vasoconstriction (37.0 (0.5)°C vs 37.1 (0.3)°C; P=0.70), or shivering threshold (36.3 (0.5)°C vs 36.3 (0.6)°C; P=0.76). No sedation was observed on either study day.
Ondansetron appears to have little potential for facilitating induction of therapeutic hypothermia.
During pregnancy, it is crucially important that the mother's immune system tolerates the developing embryo. Although a number of mechanisms of immunological tolerance have been described, little is ...known about intracellular signaling events, causing a decrease in the mother's leukocyte activity.
We investigated the expression and activity of phosphoinositide 3-kinases (PI3K) in maternal blood cells of healthy volunteers by Reverse Transcription PCR and Western blotting.
Our data reveal a selective downregulation of the p110alpha catalytic isoform. This correlated with a slight decrease in PI3K activity as judged by the levels of phosphorylated Akt. CONCLUSION As PI3K are involved in signal transduction of various leukocyte receptors, this downregulation may comprise a means of holding immune functions at bay.
Problem During pregnancy, it is crucially important that the mother’s immune system tolerates the developing embryo. Although a number of mechanisms of immunological tolerance have been described, ...little is known about intracellular signaling events, causing a decrease in the mother’s leukocyte activity.
Method of study We investigated the expression and activity of phosphoinositide 3‐kinases (PI3K) in maternal blood cells of healthy volunteers by Reverse Transcription PCR and Western blotting.
Results Our data reveal a selective downregulation of the p110α catalytic isoform. This correlated with a slight decrease in PI3K activity as judged by the levels of phosphorylated Akt.
Conclusion As PI3K are involved in signal transduction of various leukocyte receptors, this downregulation may comprise a means of holding immune functions at bay.
Verminderte oder überschießende Thrombinbildung spielt eine zentrale Rolle in der Entwicklung von Blutungen und Thrombosen. Ein supramolekularer Ansatz mit einem Oligonukleotid‐Anker (siehe Bild) ...ermöglicht die Quantifizierung von Thrombin in humanem Blut. Mit dieser Methode konnte die intraoperative Thrombinbildung während Hüftprothesenimplantation gemessen und damit das Ausmaß der Gerinnungsaktivierung unter klinischen Bedingungen bestimmt werden.
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