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At least 505 records · Page 28Linked to original sources
PubMed2005

Silver(I)-imidazole cyclophane gem-diol complexes encapsulated by electrospun tecophilic nanofibers: formation of nanosilver particles and antimicrobial activity.

Silver(I)-imidazole cyclophane gem-diol complex, 3 [Ag2C36 N10(O)4](2+)2(x)-, where x = OH- or CO3(2-), was synthesized and well characterized. The minimum inhibition concentration tests showed that the aqueous form of 3 is 2 times less effective as an antibiotic than 0.5% AgNO3, with about the same amount of silver. The antimicrobial activity of 3 was enhanced when encapsulated into Tecophilic polymer by electrospinning to obtain mats made of nano-fibers. The fiber mats released nanosilver particles, which in turn sustained the antimicrobial activity of the mats over a long period of time. The rate of bactericidal activity of 3 was greatly improved by encapsulation, and the amount of silver used was much reduced. The amount of silver contained in the fiber mat of 3, with 75% of 3 and 25% Tecophilic, was 8 times less than that in 0.5% AgNO3 and 5 times lower than that in silver sulfadiazine cream 1%. The fiber mat was found to kill S. aureus at the same rate as 0.5% AgNO3, with zero colonies on an agar plate, and about 6 times faster than silver sulfadiazine cream. The silver mats were found effective against E. coli, P. aeruginosa, S. aureus, C. albicans, A. niger, and S. cerevisiae. Transmission electron microscopy and scanning electron microscopy were used to characterize the fiber mats. The acute toxicity of the ligand (imidazolium cyclophane gem-diol dichloride) was assessed by intravenous administration to rats, with an LD 50 of 100 mg/kg of rat.

Animals↗
PubMed2004

Crystallization of silver stearate from sodium stearate dispersions.

Silver carboxylates, the common silver source used for photothermographic imaging materials, are normally obtained from the reaction between sodium soap (e.g., sodium stearate) and silver nitrate. They form platelet-like crystals with a lamellar structure in water at room temperature. Light microscopy investigations reveal that the formation of silver stearate (AgSt) crystals follows a diffusion-controlled mechanism. The reaction between the sodium soap and silver nitrate preferentially occurs in solution rather than on the soap fiber solid interface. Cryogenic transmission electron microscopy, together with an on-the-grid reaction technique, provides a useful tool to directly image silver stearate microstructures at the initial stages of AgSt precipitation. The AgSt reaction product first forms particles about 5 nm in size, which is similar to the d-spacing of final AgSt crystals. Those particles aggregate to produce larger and loosely packed embryonic crystals, the precursors to the ultimate silver stearate crystals.

Crystallization↗
PubMed2006

Silver and gold glyconanoparticles for colorimetric bioassays.

The color changes associated with the aggregation of metal nanoparticles has led to the development of colorimetric-based assays for a variety of target species. We have examined both silver- and gold-based nanoparticles in order to establish whether either metal exhibits optimal characteristics for bioassay development. These silver and gold nanoparticles have been stabilized with a self-assembled monolayer of a mannose derivative (2-mercaptoethyl alpha-d-mannopyranoside) with the aim of inducing aggregation by exploiting the well-known interaction between mannose and the lectin Concanavalin A (Con A). Both metal glyconanoparticles were determined to be ca. 16 nm in diameter (using TEM measurements). Aggregation was observed on addition of Con A to both silver and gold nanoparticles resulting in a shift in the surface plasmon absorption band and a consequent color change of the solution, which was monitored using UV-visible spectrophotometry. Mannose-stabilized silver nanoparticles at a concentration of 3 nM provide an assay for Con A with the largest linear range (between 0.08 and 0.26 microM). Additionally, the kinetic rate of aggregation of the silver-nanoparticle-based bioassay was significantly greater than that of the gold-nanoparticle system. However, in terms of sensitivity, the mannose-stabilized gold-nanoparticle-based assay was optimum with a limit of detection of 0.04 microM Con A, as compared with a value of 0.1 microM obtained for the mannose-stabilized silver nanoparticles. Additionally, a lactose derivative (11-mercapto-3,6,9-trioxaundecyl beta-D-lactoside) was used to stabilize gold nanoparticles to induce aggregation upon addition of the galactose specific lectin Ricinus communis agglutinin (RCA(120)). To examine the specificity of the bioassay, lactose-stabilized gold nanoparticles were mixed with a solution of mannose-stabilized silver nanoparticles to give an aggregation assay capable of detecting two different lectins. When either Con A or RCA(120) was added to the mixed glyconanoparticles, selective recognition of the respective natural ligand was shown by aggregation of a single metal nanoparticle. Centrifugation and removal of the aggregated species enabled further bioassay measurements using the second glyconanoparticle system.

Agglutinins↗
PubMed1998

Multiple parameters for the comprehensive evaluation of the susceptibility of Escherichia coli to the silver ion.

The susceptibility of Escherichia coli B to the antibacterial activity of silver ions was measured in terms of the initial inhibitory concentration, complete inhibitory concentration, postagent effect for bacteriostatic susceptibility, minimum bactericidal concentration, maximum tolerant concentration, and log killing time for bactericidal activity. At a concentration of 9.45 microM and an inoculum size of 10(4-5) CFU ml-1, silver caused growth delay of E. coli; at a concentration of 18.90 microM, silver completely inhibited bacterial growth. Prolonged postagent effects ranged between 1.5 and 12 h at 0.75 x the initial inhibitory concentration, 1.0 x the initial inhibitory concentration, and 1.5 x the initial inhibitory concentration of the silver ion. One log-unit of viable bacterial population size was lost every 30 min at the minimum bactericidal concentration of the silver ion. Silver tolerance was determined as 20 times the initial inhibitory concentration with 48 h of exposure. This study presents an evaluative model as a reference for the quantitative analysis of the susceptibility of bacteria to silver ions.

Anti-Infective Agents, Local↗
PubMed1993

Silver staining as a tool for neurotoxic assessment.

There is no denying that the silver methods lost their dominant role as tract-tracing methods in the past 10 to 15 years. But it seems equally clear that the silver technique is headed for a dramatic revival in many fields of neuroscience, where the scope and localization of neuronal degeneration are a central issue. Together with the immunostaining of proteins formed or altered in traumatized neurons, the modern silver techniques provide neurotoxicologists and neuropathologists with unparalleled opportunities to detect and study injured and dying neurons. Characterized by great sensitivity and distinct rendition of the morphology of degenerating neurons and their processes, the reduced silver methods constitute the ideal tool for screening irreversible neuronal damage caused by neurotoxic substances including drugs of abuse. Those interested in the rapidly expanding fields of "excitotoxicity" and neurodegenerative disorders (Taylor 1991) are also likely to find increasing use for the silver methods. The pattern of degeneration in so-called "system degenerations" may be predetermined by the neuronal connections (Saper et al. 1987), and as the disease progresses from the destruction of the originally affected neuron population, closely related systems and pathways may be recruited into the pathophysiologic cascade. Any type of trauma to the CNS has the potential to produce this type of "domino effect" of degeneration, through which additional systems are progressively recruited into a degenerative chain reaction of transneuronal degeneration. In other words, even longstanding disorders may exhibit signs of more recent degeneration, and the proper use of silver methods at autopsy may give some important clues regarding the etiology of disease; it may also provide new insights about the anatomy of the human brain. Little can be said at present about the chemical basis of argyrophilia in degenerating and "reactive" neurons, but there is every reason to pay more attention to this subject. One can expect that a continuing and concerted effort will result in a rational understanding of the molecular biological and physicochemical events that fortuitously provide the basis for the selective impregnation of degenerating neuronal elements. This knowledge can be the basis for the development of even more reliable and simple, yet sensitive, silver methods suited for neurotoxic risk assessment on a large scale.

Animals↗
PubMed2002

Recovery of intact proteins from silver stained gels.

Silver stained proteins of a wide molecular weight (MW) range (20-116 kDa) were successfully recovered by both electroblot and electroelution. The recovery was demonstrated for nanogram loads of proteins separated by SDS-PAGE and visualized by silver staining methods compatible and incompatible with mass spectrometry (MS). It was shown that the alcohol/acid and glutaraldehyde fixation steps present in a number of staining procedures did not prevent recovery of intact proteins from gels. It was found that the recovery of intact proteins from silver stained gels was substantially increased upon pre-equilibration in a buffer containing the reducing agent, dithiothreitol (DTT). The effect of destaining on the recovery of silver stained proteins was also investigated. Comparable recovery of intact proteins within a wide MW range from silver stained gels with and without destaining step was demonstrated. Recovery of model proteins from gels visualized using silver staining method compatible with MS showed 52 to 76% yield of that from the unstained gel, depending upon method of the transfer. Comparison of the recovery of intact proteins from gels visualized using other staining procedures was also made. The above findings have implications as to the supposed irreversible nature of protein "fixation" inside polyacrylamide matrix, and confirm lack of binding of proteins in the gel to metal silver deposited on its surface. This method has the potential to be suitable for direct characterization of proteins by matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) without additional purification steps.

Electrophoresis, Polyacrylamide Gel↗
PubMed1998

Degradation of a silver point in association with endodontic infection.

This paper describes an unusual clinical report of degradation of an endodontic silver point within the root canal of a lower right first premolar. Its apical portion was found to be degrading and at one stage a small portion became separated from its main body and was displaced apically. The tooth, despite past apical surgery, displayed signs of endodontic failure. Conventional retreatment and removal of the silver point improved the endodontic problems associated with this tooth. The silver point was analysed using both scanning electron microscopy and x-ray microanalyses. These tests revealed that the silver point had deteriorated significantly with a surface coating of a silver-chloride salt. Microleakage with infection and galvanic reaction are possible hypotheses as to the reason for the degradation of the silver point. Although other reports have demonstrated corrosion of silver points, this method of presentation appears unique.

Biodegradation, Environmental↗
PubMedDate not supplied

Antibacterial properties of a silver chloride-coated nylon wound dressing.

OBJECTIVE: A silver chloride-coated nylon wound dressing (Ag-WD) was evaluated in vitro for antimicrobial activity against five common equine wound pathogens. STUDY DESIGN: Bacterial susceptibility study. SAMPLE POPULATION: Equine wound pathogens: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Streptococcus equi subspecies zooepidemicus, and Staphylococcus aureus. METHODS: An inoculum of each pathogen was incubated directly with Ag-WD and quantitated after 24 to 48 hours of incubation. To determine if bactericidal activity of Ag-WD was contact dependent, an inoculum of E. coli and Staphylococcus aureus was incubated separately from Ag-WD by a filter and quantitated after 18 hours of incubation. Inductively coupled plasma emission spectrometry (ICP) determined the silver concentration of Mueller-Hinton broth containing Ag-WD after 24 hours of incubation. To establish if the rate of bacterial killing by Ag-WD differed from a constant silver concentration, pathogens were exposed to a silver concentration of 6.45 microg/mL and quantitated after 18 hours. RESULTS: Direct exposure to Ag-WD significantly reduced bacterial numbers after 15 minutes for K. pneumoniae, 30 minutes for E. coli, 1 hour for P. aeruginosa, and 2 hours for S. equi subspecies zooepidemicus and Staphylococcus aureus. Indirect exposure to Ag-WD resulted in > or =99.9% and > or =90% kill of the inoculum doses of E. coli at 2 hours and Staphylococcus aureus at 18 hours, respectively. Incubation of the pathogens at the constant silver concentration resulted in bacterial killing rates similar to those obtained by incubation with Ag-WD. CONCLUSIONS: In vitro, equine pathogens are effectively killed when exposed to Ag-WD, and the rate of bacterial killing by Ag-WD is similar to a constant silver concentration of 6.45 microg/mL. CLINICAL RELEVANCE: The in vitro antimicrobial properties of this silver-coated nylon wound dressing are promising for future prevention of equine wound infections.

Animals↗
PubMed1991

[Silver nitrate burn after Credé's preventive treatment. A roentgen analytic and scanning electron microscopy study].

Following Credé's prophylaxis with silver-nitrate, the cornea of a newborn presented greyish-brown, lime-like plaques on the nasal part of the right eye. A paracentral ulcerating stromal opacification undermined these appositions, when the patient was admitted to the eye-clinic at Aachen. In the material taken in a lamellar keratectomy scanning electron microscopical examination was able to prove the existence of granules, previously described in light-microscopy. These granules measured 100 to 300 nm in diameter and were placed up to 110 microns deep into the corneal stroma of the specimen. An earlier chemical analysis of necrotic material showed no silver specific reaction. By means of EDX-Analysis these granules could be identified as silver-containing. This was once reassured by a newly developed modification of van-Kossa's-staining-method. The fact that the granular deposits contained mainly silver proves that the onset of a sodium-chloride-irrigation did not promote an intended therapeutic silver-chloride-precipitation and therefore had no effects on the silver-nitrate's penetration abilities. Injuries by silver-nitrate-solutions used for Credé's prophylaxis are seldom but still reported. The mechanism of injury in this case of a child, born by sectio remains unknown. Neither the use of an unusual silvernitrate solution, that was taken from a disposable ampoule (Mova-Nitrat) was reported, nor any corneal injury during sectio mentioned.(ABSTRACT TRUNCATED AT 250 WORDS)

Burns, Chemical↗
PubMed2002

Use of silver-hydrogel urinary catheters on the incidence of catheter-associated urinary tract infections in hospitalized patients.

BACKGROUND: Urinary tract infections (UTIs) account for 40% of all nosocomial infections, and about 80% of these are associated with the use of urinary catheters. They not only contribute to excess morbidity and mortality, but they also significantly add to the cost of hospitalization. Clinical trials with silver-coated urinary catheters have shown conflicting results. However, recent trials with silver-hydrogel urinary catheters have shown a reduction in nosocomial UTIs, and these catheters appear to offer cost savings. METHOD: The University of Massachusetts Medical Center is a teaching, tertiary hospital with 18% of its beds in intensive care units. The silver-hydrogel urinary catheters were introduced in October 1997. The rate of catheter-associated UTIs with silver-hydrogel urinary catheter use was compared with a historical baseline UTI rate that was established for January 1996 and January 1997 with the standard, noncoated catheters. The cost of a nosocomial catheter-associated UTI was estimated by calculating the hospital charges resulting from all urinary catheter-associated UTIs in 1 month. A cost-analysis of silver-hydrogel urinary catheter use was performed. RESULTS: The rate of catheter-associated UTIs for noncoated catheters was 4.9/1000 patient-days compared with 2.7/1000 patient-days for the silver-hydrogel catheters, a reduction of 45% (P =.1). The average cost (calculated with hospital charges) of a catheter-associated UTI at our institution was estimated to be $1214.42 US dollars, with a median of $613.72 US dollars. The estimated cost-saving ranged from $12,563.52 US dollars to $142,314.72 US dollars. CONCLUSIONS: The use of silver-hydrogel urinary catheters resulted in a nonsignificant reduction in catheter-associated UTIs and a modest cost-saving.

Adult↗
PubMed1992

Monoclonal antibody to Pneumocystis carinii. Comparison with silver stain in bronchial lavage specimens.

Monoclonal 3F6 anti-Pneumocystis carinii antibody (MAB-3F6) was used to stain cell blocks from 164 bronchial lavage specimens from patients with the acquired immune deficiency syndrome (AIDS) and AIDS-related complex and compared with slides stained with Grocott's modification of the Gomori methenamine silver stain. Pneumocystis organisms were present in 83 of 164 cases using MAB-3F6 stain, whereas Grocott's modified silver stain demonstrated Pneumocystis organisms in 48. MAB-3F6 demonstrated Pneumocystis organisms in 38 cases with negative silver stains, whereas silver stain identified Pneumocystis organisms in only three MAB-3F6-negative cases. Of 70 patients with clinical Pneumocystis pneumonia at the time of the specimen was obtained, 59 had MAB-3F6-positive specimens, whereas 39 had organisms detected using Grocott's modified silver stain. Of 37 patients without clinically apparent Pneumocystis pneumonia any time in their course, 4 had abundant organisms and 33 had negative stains with MAB-3F6. MAB-3F6 detected Pneumocystis organisms in 22 of 31 cases of Pneumocystis pneumonia that had no organisms identified using Grocott's silver stain (X2 = 5.76, P = 0.016). MAB-3F6 immunochemical staining is a more sensitive method than Grocott's modified silver stain to detect Pneumocystis organisms.

Antibodies, Monoclonal↗
PubMed1992

Comparison of the in-vitro activities of the topical antimicrobials azelaic acid, nitrofurazone, silver sulphadiazine and mupirocin against methicillin-resistant Staphylococcus aureus.

The in-vitro activities of the topical agents azelaic acid, nitrofurazone, silver sulphadiazine and mupirocin have been determined against 80 strains of MRSA collected from worldwide sources. MICs were determined by agar dilution (with an inoculum of approximately 5.0 x 10(5) cfu) in Iso-Sensitest agar, and MBCs were measured by replica-plating from MIC plates using velvet pads. The agents tested were uniformly active against MRSA, mupirocin being the most active (MIC50 0.15 mg/L) followed by nitrofurazone (MIC50 19 mg/L), silver sulphadiazine (MIC50 85 mg/L) and azelaic acid (MIC50 850 mg/L). Concentrations of azelaic acid, nitrofurazone and silver sulphadiazine close to the MIC were bactericidal, but mupirocin was only bactericidal at concentrations substantially greater than the MIC. In time-kill experiments, azelaic acid and nitrofurazone were gradually bactericidal, silver sulphadiazine was rapidly bactericidal and mupirocin was not bactericidal. Silver sulphadiazine killed sulphonamide-sensitive and sulphonamide-resistant strains equally rapidly. No resistant mutants were found to azelaic acid, nitrofurazone or silver sulphadiazine in an inoculum of 10(9) cfu, but two strains yielded (frequency: 1.0 x 10(-9)) mutants resistant to mupirocin. Our in-vitro results suggest azelaic acid, nitrofurazone and silver sulphadiazine could be of use for clearing staphylococcal carriage.

Anti-Bacterial Agents↗
PubMed1998

Effects of sucrose and silver on Staphylococcus aureus biofilms.

The present study examined the effects of antimicrobial agents on a biofilm model of Staphylococcus aureus. A membranous structure (an immature biofilm) was formed on the coverslips of tissue culture dishes by S. aureus cells in plasma after incubation for 24 h. After incubation, the colony counts of S. aureus cells in the immature biofilms in plasma containing levofloxacin with 70% sucrose were about one-tenth of those in plasma containing levofloxacin without sucrose. The colony counts of S. aureus cells in the immature biofilms in plasma containing silver sulphadiazine or silver nitrate (at a silver concentration of 0.302%) were over 3000 times lower than those in control plasma without silver after incubation for 24 h. Plasma coagulation by S. aureus cells was not detected in plasma containing 70% sucrose 48 h after inoculation. The immature biofilms were incubated in plasma with and without 70% sucrose, and the immature biofilms were treated with 10% povidone-iodine for 2 min after incubation for 4 and 16 h. In this experiment, the colony counts of S. aureus cells in the immature biofilms incubated with 70% sucrose were about one-tenth of those in plasma without sucrose after incubation for 24 h. We suggest that levofloxacin or 10% povidone-iodine in combination with 70% sucrose and silver sulphadiazine or silver nitrate (at a silver concentration of 0.302%) are effective in eliminating S. aureus cells in a biofilm.

Anti-Infective Agents↗
PubMed2004

Silver nanoparticles and polymeric medical devices: a new approach to prevention of infection?

OBJECTIVES: Implantable devices are major risk factors for hospital-acquired infection. Biomaterials coated with silver oxide or silver alloy have all been used in attempts to reduce infection, in most cases with controversial or disappointing clinical results. We have developed a completely new approach using supercritical carbon dioxide to impregnate silicone with nanoparticulate silver metal. This study aimed to evaluate the impregnated polymer for antimicrobial activity. METHODS: After impregnation the nature of the impregnation was determined by transmission electron microscopy. Two series of polymer discs were then tested, one washed in deionized water and the other unwashed. In each series, half of the discs were coated with a plasma protein conditioning film. The serial plate transfer test was used as a screen for persisting activity. Bacterial adherence to the polymers and the rate of kill, and effect on planktonic bacteria were measured by chemiluminescence and viable counts. Release rates of silver ions from the polymers in the presence and absence of plasma was measured using inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: Tests for antimicrobial activity under various conditions showed mixed results, explained by the modes and rates of release of silver ions. While washing removed much of the initial activity there was continued release of silver ions. Unexpectedly, this was not blocked by conditioning film. CONCLUSIONS: The methodology allows for the first time silver impregnation (as opposed to coating) of medical polymers and promises to lead to an antimicrobial biomaterial whose activity is not restricted by increasing antibiotic resistance.

Anti-Bacterial Agents↗
PubMed2005

Thermodynamic analyses of the specific interaction between C:C mismatch base pair and silver (I) cation: toward the efficient detection of single nucleotide polymorphism.

We examined the effect of silver (I) cation on the thermal stability of heteroduplex and homoduplex. Addition of silver (I) cation increased the melting temperature of heteroduplex containing C:C mismatch base pair by about 4 degrees C. The thermal stability of homoduplex and heteroduplexes containing other kinds of mismatch base pairs was not significantly changed by the addition of silver (I) cation. Isothermal titration calorimetric study demonstrated that silver (I) cation directly bound to C:C mismatch base pair in heteroduplex at a molar ratio of 1:1. The binding constant and the enthalpy change for the binding of silver (I) cation to C:C mismatch base pair was approximately 10(6) M(-1) and -3 kcal mol(-1), respectively. We conclude that silver (I) cation directly binds to C:C mismatch base pair in heteroduplex with high affinity and specificity. Our results certainly support the idea that the addition of silver (I) cation to C:C mismatch base pair in heteroduplex could be a convenient strategy for heteroduplex analysis and may eventually lead to progress in single nucleotide polymorphism genotyping.

Base Pair Mismatch↗
PubMedDate not supplied

Cross-linked silver-impregnated skin for burn wound management.

Biological skin is effective in restoring the missing water vapor barrier and promoting healing in burn wounds. Its effectiveness in wound management has been limited, however, by its inherently limited antibacterial properties and the fact that it is sometimes rejected before healing is complete, even reversing previous beneficial effects. Limited availability and storage difficulties have posed further problems. Impregnation of biological skin with silver ions has been proven to provide a potent bactericidal effect directly at the wound surface. We hypothesized that aldehyde cross-linking of silver-impregnated skin would mask the histocompatibility sites from the recipient's immune system. This has been demonstrated previously with aldehyde cross-linking of allografts and xenografts, prolonging retention sufficiently to permit complete wound healing. Commercially available skin was treated with an aldehyde compound and impregnated with silver. Initial studies of this cross-linked skin for treatment of burn wounds showed average retention to be between 117 and 161 days, far exceeding that of any untreated skin. It was subsequently found that the aldehyde cross-linking permitted impregnation with higher concentrations of silver than had previously been possible--2,600 to 2,830 ppm as compared to an average of 1,020 to 1,350 ppm in previously available silver-impregnated skin. This results in a more potent, immediate antibacterial effect at the wound surface and an extended period of time-release antibacterial action before the silver is exhausted. The antibacterial properties of this aldehyde cross-linked silver-impregnated skin are effective in decontaminating even grossly infected wounds and in protecting against contamination of clean wounds from adjacent infected areas or external sources.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2004

A scanning electron microscope examination of silver cones removed from endodontically treated teeth. 1972.

Twenty-five silver cones were removed from teeth which had been treated endodontically from 3 months to 20 years previously. Examination by the scanning electron microscope revealed that these cones were moderately to severely corroded. The corrosion patterns were described as ranging from pitting to deep crater formation with globular or spherical agglomerations. Examinations with the electron probe showed sulfur peaks on the corroded portions of the cones. X-ray diffraction analyses indicated that the chemical compounds formed were silver sulfides, silver sulfates, silver carbonates, and silver amine sulfate amide hydrates. Tissue culture studies indicated that the corrosion products were highly cytotoxic. The mechanisms for the formation of the corrosion products have been postulated as being due to plastic deformations and metal transfer to the silver cones, plus contact of the silver with tissue fluids.

Corrosion↗
PubMed1985

Synergistic action of silver sulfadiazine and sodium piperacillin on resistant Pseudomonas aeruginosa in vitro and in experimental burn wound infections.

Silver sulfadiazine-resistant organisms are arising at an irregular rate and may eventually interfere with wound management. To counter this problem several new antibacterial agents were tested in combination with silver sulfadiazine. Only sodium piperacillin (Pipracil, Lederle) exhibited synergism with silver sulfadiazine both in vitro (against various species of organisms) and in burned animals. The MIC of AgSD and Pipracil was 50 nmole/ml and 250 nmole/ml, respectively, but a combination of 6 nmole/ml of AgSD and 7.5 nmole/ml of Pipracil inhibited the growth of Pseudomonas aeruginosa. In burned mice infected with either AgSD-resistant or sensitive strains, the mortality in groups receiving combinations of topical Pipracil and silver sulfadiazine was 0-10%; in contrast, treatment with Pipracil or silver sulfadiazine alone resulted in much higher mortality. Thus it would appear that a combination of silver sulfadiazine and Pipracil, each of which have long been used in patients topically and parenterally, may prove valuable in patients with burn wound infections related to or caused by organisms resistant to silver sulfadiazine.

Administration, Topical↗