Publications by authors named "Anthony Duncan"

11 Publications

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Achieving the Optimal Aesthetic Benefit While Correcting Midface Deficiency: Utilizing A High Winged Le Fort I in Cleft and Craniofacial Patients.

J Craniofac Surg 2021 Jan-Feb 01;32(1):46-50

Department of Surgery, Section of Plastic and Reconstructive Surgery.

Abstract: Craniofacial anomalies are congenital disorders that affect the cranium and facial bones, with cleft lip and palate being the most common. These anomalies are often associated with abnormal development of pharyngeal arches and can result in the development of class III malocclusion and severe maxillary retrusion. Current treatment includes orthodontic decompensation and Le Fort I osteotomy to correct the maxillomandibular relationship. However, the traditional Le Fort I (LFI) advancement does not fully address the lack of skeletal volume in the midface. The high winged Le Fort I osteotomy (HWLFI) is an excellent surgical option for simultaneous correction of the midface deficiency and malocclusion while restoring optimal esthetic convexity. A retrospective chart review was conducted to include all cleft and craniofacial patients who underwent HWLFI advancement from 2002 to 2018. Patients had a minimum of 12 months of follow-up. Patient data and complications were reviewed. Standardized facial photographs were analyzed for esthetic improvement, occlusion, and beneficial salutary effects on the midface. Forty-three patients met the inclusion criteria. The mean age at surgery was 18.9 years. The mean follow-up was 32 months. Early complications included infection (9.3%) and temporary nerve paresthesia (2.3%). Late complications included infection (6.5%), wound dehiscence (4.3%), and painful hardware (2.3%). One patient (2.3 percent) had clinically significant relapse that required surgery. Postoperatively, patients demonstrated excellent midface projection and correction of the skeletal malocclusion. The HWLFI advancement significantly improves both the malocclusion and esthetic concerns of cleft and craniofacial patients by reestablishing maximal midfacial support. Important advantages of the HWLFI are avoidance of alloplastic implant use and extensive and potentially unstable surgical procedures that increase orbital volume.
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http://dx.doi.org/10.1097/SCS.0000000000006871DOI Listing
August 2020

Chronic wound healing: A specific antibiofilm protein-asymmetric release system.

Mater Sci Eng C Mater Biol Appl 2020 Jan 24;106:110130. Epub 2019 Aug 24.

Normandie Univ, UNIRouen Normandie, INSA Rouen, CNRS, PBS, 76000 Rouen, France. Electronic address:

Chronic infection is a major cause of delayed wound-healing. It is recognized to be associated with infectious bacterial communities called biofilms. Currently used conventional antibiotics alone often reveal themselves ineffective, since they do not specifically target the wound biofilm. Here, we report a new conceptual tool aimed at overcoming this drawback: an antibiofilm drug delivery system targeting the bacterial biofilm as a whole, by inhibiting its formation and/or disrupting it once it is formed. The system consists of a micro/nanostructured poly(butylene-succinate-co-adipate) (PBSA)-based asymmetric membrane (AM) with controlled porosity. By the incorporation of hydrophilic porogen agents, polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG), we were able to obtain AMs with high levels of porosity, exhibiting interconnections between pores. The PBSA-PEG membrane presented a dense upper layer with pores small enough to block bacteria penetration. Upon using such porogen agents, under dry and wet conditions, membrane's integrity and mechanical properties were maintained. Using bovine serum albumin (BSA) as a model protein, we demonstrated that protein loading and release from PBSA membranes were affected by the membrane structure (porosity) and the presence of residual porogen. Furthermore, the release curve profile consisted of a fast initial slope followed by a second slow phase approaching a plateau within 24 h. This can be highly beneficial for the promotion of wound healing. Cross-sectional confocal laser scanning microscopy (CLSM) images revealed a heterogeneous distribution of fluorescein isothiocyanate (FITC) labeled BSA throughout the entire membrane. PBSA membranes were loaded with dispersin B (DB), a specific antibiofilm matrix enzyme. Studies using a Staphylococcus epidermidis model, indicate significant efficiency in both inhibiting or dispersing preformed biofilm (up to 80 % eradication). The asymmetric PBSA membrane prepared with the PVP porogen (PBSA-PVP) displayed highest antibiofilm activity. Moreover, in vitro cytotoxicity assays using HaCaT and reconstructed human epidermis (RHE) models revealed that unloaded and DB-loaded PBSA-PVP membranes had excellent biocompatibility suitable for wound dressing applications.
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http://dx.doi.org/10.1016/j.msec.2019.110130DOI Listing
January 2020

Breast Cancer Knowledge and Decisions Made for Contralateral Prophylactic Mastectomy: A Survey of Surgeons and Women in the General Population.

Plast Reconstr Surg 2019 05;143(5):936e-945e

From the Section of Plastic Surgery, Department of Surgery, University of Michigan Health System; the Department of Surgery, Henry Ford Health System; and the Department of Biostatistics, University of Michigan School of Public Health.

Background: Decisions made to undergo contralateral prophylactic mastectomy, in women at low risk for bilateral disease, are often attributed to a lack of knowledge. This study examines the role knowledge plays in determining surgical treatment for unilateral breast cancer made by laywomen and surgeons for themselves or loved ones.

Methods: The study cohort had three groups: (1) laywomen in the general population, (2) breast surgeons, and (3) plastic surgeons. Laywomen were recruited using Amazon Mechanical Turk Crowd Sourcing. Breast and plastic surgeons from nine states were sent electronic surveys. Demographic and contralateral prophylactic mastectomy-specific data on decisions and knowledge were collected and analyzed.

Results: Surveys from 1333 laywomen, 198 plastic surgeons, and 142 breast surgeons were analyzed. A significantly greater proportion of laywomen in the general population favored contralateral prophylactic mastectomy (67 percent) relative to plastic (50 percent) and breast surgeons (26 percent) (p < 0.0001). Breast surgeons who chose contralateral prophylactic mastectomy were younger (p = 0.044) and female (0.012). On assessment of knowledge, 78 percent of laywomen had a low level of breast cancer knowledge. Laywomen with higher levels of breast cancer knowledge had lower odds of choosing contralateral prophylactic mastectomy (OR, 0.37; 95 percent CI, 0.28 to 0.49).

Conclusions: Fewer women are likely to make decisions in favor of contralateral prophylactic mastectomy with better breast cancer-specific education. A knowledge gap likely explains the lower rates with which surgeons choose contralateral prophylactic mastectomy for themselves or loved ones; however, some surgeons who were predominantly young and female favor contralateral prophylactic mastectomy. Improving patient education on surgical options for breast cancer treatment is critical, with well-informed decisions as the goal.
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http://dx.doi.org/10.1097/PRS.0000000000005523DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6724742PMC
May 2019

The Cost of Contralateral Prophylactic Mastectomy in Women with Unilateral Breast Cancer.

Plast Reconstr Surg 2018 05;141(5):1094-1102

Ann Arbor, Mich.; and Baltimore, Md.

Background: Contralateral prophylactic mastectomy may be unnecessary from an oncologic perspective; therefore, the debate persists about the value of contralateral prophylactic mastectomy in women with early-stage unilateral breast cancer. Given finite health care resources, this study aims to evaluate the cost of contralateral prophylactic mastectomy and breast reconstruction.

Methods: Women with unilateral breast cancer undergoing either unilateral mastectomy or unilateral mastectomy with contralateral prophylactic mastectomy and immediate breast reconstruction were selected from the Truven MarketScan databases between 2009 and 2013. Demographic and treatment data were recorded, and over an 18-month follow-up period, the treatment cost was tallied. A log-transformed linear model was used to compare cost between the groups.

Results: A total of 2343 women were identified who met our inclusion criteria, with 1295 undergoing unilateral mastectomy and 1048 undergoing contralateral prophylactic mastectomy. Complication rates within 18 months were similar for women undergoing unilateral mastectomy and contralateral prophylactic mastectomy (39 percent versus 42 percent; p = 0.17). Management with unilateral mastectomy with reconstruction required an adjusted cumulative mean cost of $33,557. Contralateral prophylactic mastectomy with reconstruction was an additional $11,872 in expenditure (p < 0.001). The cost of initial procedures (mean difference, $6467) and secondary procedures (mean difference, $2455) were the greatest contributors to cost.

Conclusions: In women with unilateral breast cancer, contralateral prophylactic mastectomy with reconstruction is more costly. The increased monetary cost of contralateral prophylactic mastectomy may be offset by improved quality of life. However, this financial reality is an important consideration when ongoing efforts toward reimbursement reform may not pay for contralateral prophylactic mastectomy if outcomes data are not presented to justify this procedure.
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http://dx.doi.org/10.1097/PRS.0000000000004272DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5922428PMC
May 2018

Designing Biodegradable PHA-Based 3D Scaffolds with Antibiofilm Properties for Wound Dressings: Optimization of the Microstructure/Nanostructure.

ACS Biomater Sci Eng 2017 Dec 28;3(12):3654-3661. Epub 2017 Nov 28.

Normandie University, UNIROUEN, INSA Rouen, CNRS, PBS, 76000 Rouen, France.

One major factor inhibiting natural wound-healing processes is infection through bacterial biofilms, particularly in the case of chronic wounds. In this study, the micro/nanostructure of a wound dressing was optimized in order to obtain a more efficient antibiofilm protein-release profile for biofilm inhibition and/or detachment. A 3D substrate was developed with asymmetric polyhydroxyalkanoate (PHA) membranes to entrap Dispersin B (DB), the antibiofilm protein. The membranes were prepared using wet-induced phase separation (WIPS). By modulating the concentration and the molecular weight of the porogen polymer, polyvinylpyrrolidone (PVP), asymmetric membranes with controlled porosity were obtained. PVP was added at 10, 30, and 50% w/w, relative to the total polymer concentration. The physical and kinetic properties of the quaternary nonsolvent/solvent/PHA/PVP systems were studied and correlated with the membrane structures obtained. The results show that at high molecular weight ( = 360 kDa) and high PVP content (above 30%), pore size decreased and the membrane became extremely brittle with serious loss of physical integrity. This brittle effect was not observed for low molecular weight PVP ( = 40 kDa) at comparable contents. Whatever the molecular weight, porogen content up to 30% increased membrane surface porosity and consequently protein uptake. Above 30% porogen content, the pore size and the physical integrity/mechanical robustness both decreased. The PHA membranes were loaded with DB and their antibiofilm activity was evaluated against biofilms. When the bacterial biofilms were exposed to the DB-loaded PHA membrane, up to 33% of the biofilm formation was inhibited, while 26% of the biofilm already formed was destroyed. These promising results validate our approach based on the development of bioactive-protein-loaded asymmetric membranes for antibiofilm strategies in situations where traditional antibiotic therapies are ineffective.
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http://dx.doi.org/10.1021/acsbiomaterials.7b00552DOI Listing
December 2017

Probability of Opioid Prescription Refilling After Surgery: Does Initial Prescription Dose Matter?

Ann Surg 2018 08;268(2):271-276

Assistant Professor, Section of Plastic Surgery, Department of Surgery, University of Michigan Health System, Ann Arbor, MI.

Objective: We sought to determine the correlation between the probability of postoperative opioid prescription refills and the amount of opioid prescribed, hypothesizing that a greater initial prescription yields a lower probability of refill.

Background: Although current guidelines regarding opioid prescribing largely address chronic opioid use, little is known regarding best practices and postoperative care.

Methods: We analyzed Optum Insight claims data from 2013 to 2014 for opioid-naïve patients aged 18 to 64 years who underwent major or minor surgical procedures (N = 26,520). Our primary outcome was the occurrence of an opioid refill within 30 postoperative days. Our primary explanatory variable was the total oral morphine equivalents provided in the initial postoperative prescription. We used logistic regression to examine the probability of an additional refill by initial prescription strength, adjusting for patient factors.

Results: We observed that 8.67% of opioid-naïve patients refilled their prescriptions. Across procedures, the probability of a single postoperative refill did not change with an increase with initial oral morphine equivalents prescribed. Instead, patient factors were correlated with the probability of refill, including tobacco use [odds ratio (OR) 1.42, 95% confidence interval (CI) 1.23-1.57], anxiety (OR 1.30, 95% CI 1.15-1.47), mood disorders (OR 1.28. 95% CI 1.13-1.44), alcohol or substance abuse disorders (OR 1.43, 95% CI 1.12-1.84), and arthritis (OR 1.21, 95% CI 1.10-1.34).

Conclusions: The probability of refilling prescription opioids after surgery was not correlated with initial prescription strength, suggesting surgeons could prescribe smaller prescriptions without influencing refill requests. Future research that examines the interplay between pain, substance abuse, and mental health could inform strategies to tailor opioid prescribing for patients.
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http://dx.doi.org/10.1097/SLA.0000000000002308DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7041231PMC
August 2018

Surface composition XPS analysis of a plasma treated polystyrene: Evolution over long storage periods.

Colloids Surf B Biointerfaces 2016 Sep 14;145:1-7. Epub 2016 Apr 14.

Institut de Science des matériaux de Mulhouse (IS2M) - LRC CNRS, 15 rue de Jean Starcky B.P. 2488, 68057 Mulhouse cedex, France. Electronic address:

A polystyrene surface (PS) was initially treated by cold nitrogen and oxygen plasma in order to incorporate in particular amine and hydroxyl functions, respectively. The evolution of the chemical nature of the surface was further monitored over a long time period (580 days) by chemical assay, XPS and contact angle measurements. Surface density quantification of primary amine groups was performed using three chemical amine assays: 4-nitrobenzaldehyde (4-NBZ), Sulfo succinimidyl 6-[3'(2 pyridyldithio)-pionamido] hexanoate (Sulfo-LC-SPDP) and iminothiolane (ITL). The results showed amine densities were in the range of 2 per square nanometer (comparable to the results described in the literature) after 5min of nitrogen plasma treatment. Over the time period investigated, chemical assays, XPS and contact angles suggest a drastic significant evolution of the chemical nature of the surface within the first two weeks. Beyond that time period and up to almost two years, nitrogen plasma modified substrates exhibits a slow and continuous oxidation whereas oxygen plasma modifed polystyrene surface is chemically stable after two weeks of storage. The latter appeared to "ease of" showing relatively mild changes within the one year period. Our results suggest that it may be preferable to wait for a chemical "stabilization" period of two weeks before subsequent covalent immobilization of proteins onto the surface. The originality of this work resides in the study of the plasma treated surface chemistry evolution over long periods of storage time (580 days) considerably exceeding those described in the literature.
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http://dx.doi.org/10.1016/j.colsurfb.2016.04.026DOI Listing
September 2016

Elucidation of innovative antibiofilm materials.

Colloids Surf B Biointerfaces 2015 Dec 12;136:56-63. Epub 2015 Aug 12.

Normandy University, France; Université de Rouen, Laboratoire Polymères, Biopolymères et Surfaces, Bd. Maurice de Broglie, F-76821 Mont Saint Aignan Cedex, France; CNRS, UMR 6270 & FR 3038, F-76821 Mont Saint Aignan Cedex, France. Electronic address:

It is known for roughly a decade that bacterial communities (called biofilms) are responsible for significant enhanced antibiotherapy resistance. Biofilms are involved in tissue persistent infection, causing direct or collateral damage leading to chronic wounds development and impairing natural wound healing. In this study, we are interested in the development of supported protein materials which consist of asymmetric membranes as reservoir supports for the incorporation and controlled release of biomolecules capable of dissolving biofilms (or preventing their formation) and their use as wound dressing for chronic wound treatment. In a first step, polyhydroxyalkanoates (PHAs) asymmetric membranes were prepared using wet phase inversion technique. Scanning microscopy (SEM) analysis has showed the influence of different processing parameters. In a second step, the porous side of the membranes were functionalized with a surface treatment and then loaded with the antibiofilm agent (dispersin B). In a third step, the properties and antibiofilm performance of the loaded-membranes were evaluated. Exposure of Staphylococcus epidermidis biofilms to such systems weakly inhibited biofilm formation (weak preventive effect) but caused their detachment and disaggregation (strong curative effect). These initial results are promising since they open the way to a new generation of effective tools in the struggle against persistent bacterial infections exhibiting enhanced antibiotherapy resistance, and in particular in the case of infected chronic wounds.
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http://dx.doi.org/10.1016/j.colsurfb.2015.08.007DOI Listing
December 2015

Surface assembly on biofunctional magnetic nanobeads for the study of protein-ligand interactions.

Colloids Surf B Biointerfaces 2009 Feb 26;68(2):125-9. Epub 2008 Jul 26.

Biophysic Laboratory, Faculty of Medicine of Monastir-5019 Monastir, Tunisia.

One of the major challenges of proteomics today is to increase the power potential for the identification of as many proteins as possible and to characterize their interactions with specific free ligands (interactomics) or present on cell walls (cell marker), in order to obtain a global, integrated view of disease processes, cellular processes and networks at the protein level. The work presented here proposes the development of biofunctionalized magnetic nanobeads that might be used for interactomic investigations. The strategy consisted in immobilizing proteins via a non covalent technique that provides greater possibilities for the advent of faster, cheaper and highly miniaturizable protein analysis systems, in particular in situations where the amount of isolated protein is scarce (trace proteins). The advantage of the immobilization technique proposed here over more conventional covalent binding techniques is that it is versatile and universal (not protein specific) thus applicable to a wide range of proteins, in "mild" conditions that are non deleterious to the native structure and bioactivity of the immobilized protein. The feasibility of the technique was investigated using a model protein (streptavidin). The nanobeads were analyzed in size by light diffusion and transmission electronic spectroscopy, and in quantity of immobilized protein using a bioassay developed in the laboratory. Results are promising in that nanobeads exhibited good colloidal stability and surface concentrations in the monolayer range.
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http://dx.doi.org/10.1016/j.colsurfb.2008.07.006DOI Listing
February 2009

Partitioning of a polymer chain between a confining cavity and a gel.

Phys Rev E Stat Nonlin Soft Matter Phys 2007 Oct 16;76(4 Pt 1):041804. Epub 2007 Oct 16.

Department of Chemistry, Northeastern Illinois University, Chicago, Illinois 60625, USA.

A lattice field theory approach to the statistical mechanics of charged polymers in electrolyte solutions [S. Tsonchev, R. D. Coalson, and A. Duncan, Phys. Rev. E 60, 4257 (1999)] is applied to the study of a polymer chain contained in a spherical cavity but able to diffuse into a surrounding gel. The distribution of the polymer chain between the cavity and the gel is described by its partition coefficient, which is computed as a function of the number of monomers in the chain, the monomer charge, and the ion concentrations in the solution.
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http://dx.doi.org/10.1103/PhysRevE.76.041804DOI Listing
October 2007

Bioengineering and characterization of DNA-protein assemblies floating on supported membranes.

Methods Mol Biol 2005 ;300:349-68

Department LPMO Institut FEMTO-ST UMR 617U, Besançon, France.

This chapter describes the design, practical construction, and characterization of P-DNA and their applications in building a new generation of DNA chips. P-DNAs are artificial covalent assemblies involving a histidine tag head able to bind to modified phospholipids, a core protein domain derived from cytochrome b5 by genetic engineering that features specific spectroscopic and electrochemical properties useful for detection, a synthetic linker acting as a spacer, and an oligonucleotide acting as a probe. P-DNA has the property of being able to efficiently self-associate to a supported bilayer including nickel-iminodiacetate-modified phospholipids. The construction of P-DNA and its interaction with a complementary oligonucleotide sequence can be monitored in real time by surface plasmon resonance using a Biacore system or equivalent. P-DNA chips feature unique properties including tunable surface density of probes; very low nonspecific interaction with external DNA; lateral mobility, minimizing-steric interaction; optimization of hybridization efficiency; and, potentially, recognition by multiple probes of a single target and perfectly defined and homogeneous structure, permitting high density up to a compact monolayer. Potential applications of this new device are multiple, including high-sensitivity and high-selectivity chips for DNA-DNA, DNA-RNA, or DNA-protein interactions.
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http://dx.doi.org/10.1385/1-59259-858-7:349DOI Listing
April 2005