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Charcot's neuroarthropathy complicated by calcaneal osteomyelitis can be difficult to treat. Various surgical techniques describe how to manage these conditions. Eggshell-type debridement with application of antibiotic-impregnated bone substitute is a viable option that eliminates infected bone and allows staged reconstructive surgery. A 50-year-old woman with right midfoot Charcot's neuroarthropathy presented with osteomyelitis of the cuboid and fourth and fifth metatarsal bases after resection and failed antibiotic therapy. The patient eventually developed adductovarus, septic shock, and hematogenous osteomyelitis of the calcaneus, navicular, and lateral cuneiform. Vacuum-assisted eggshell-type debridement was performed, and the calcaneal defect was filled with antibiotic-impregnated calcium sulfate and calcium phosphate. Eight weeks after the initial surgery, the infection resolved; however, the patient had trouble walking. She underwent staged Charcot's reconstructive surgery with application of a dynamic multiplanar external fixator with gradual deformity and split-thickness skin graft to cover the residual plantar lateral foot wound. The second stage included septic fusion of the midfoot and subtalar joint from the frame. Twelve weeks postoperatively, radiographic union was achieved, the external fixator was removed, and the patient demonstrated a plantigrade foot. She was transitioned to a total-contact cast and allowed to bear weight as tolerated. Eighteen months after the initial procedure, the patient is wound-free and weightbearing in a CROW boot. This innovative eggshell-type debridement technique aspirates osteomyelitic cancellous bone while preserving cortical bone. It can be particularly useful in hematogenous osteomyelitis, where cortical integrity is not breached, or in situations where there is minimal cortical involvement. Specifically preserving the calcaneus, a major weightbearing bone, permits subsequent reconstructive surgical planning. At 18 months, there were no signs of osteomyelitis recurrence.

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BACKGROUND: Bone and periarticular tissue discoloration can be an unexpected finding that is often disconcerting for surgeons and may alter surgical plans and overall patient management. Common causes of bone discoloration include infection, avascular necrosis, and bone inflammation. Minocycline-induced black bone disease is a rare and relatively benign abnormality encountered in foot and ankle surgery that can cause significant black, blue, and gray discoloration of bone. METHODS: Unanticipated intraoperative findings of diffuse black, blue, and gray bone discoloration during an elective forefoot operation raised concern for a metabolically malignant process and prompted the conversion of plans for a first metatarsophalangeal joint implant arthroplasty to a Keller arthroplasty. The plan for proximal interphalangeal joint arthroplasties of the lesser digits were continued as planned. Bone specimens were sent for pathologic analysis. RESULTS: Postoperative analysis identified chronic use of a minocycline for acne vulgaris. Pathologic analysis of the specimens ruled out malignant processes. Altogether, the data available led to the diagnosis of minocycline-induced black bone disease. Since the last follow-up, the patient has healed well without complications. CONCLUSIONS: Our case report underscores the importance of including the chronic use of tetracyclines in medical history intake during preoperative visits to assist the surgeon in intraoperative decision-making.

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The pharmacological activity and medicinal significance of Amauroderma rugosum (AR) have rarely been documented. We examined the antioxidant and neuroprotective effects of AR on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in an SH-SY5Y human neuroblastoma cell model of Parkinson's disease (PD) and explored the active ingredients responsible for these effects. The results showed that the AR aqueous extract could scavenge reactive oxygen species and reduce SH-SY5Y cell death induced by 6-OHDA. In addition, the AR aqueous extract increased the survival of Caenorhabditis elegans upon juglone-induced toxicity. Among the constituents of AR, only polysaccharides and gallic acid exhibited antioxidant and neuroprotective effects. The AR aqueous extract reduced apoptosis and increased the expression of phospho-Akt, phospho-mTOR, phospho-MEK, phospho-ERK, and superoxide dismutase-1 in 6-OHDA-treated SH-SY5Y cells. The polysaccharide-rich AR extract was slightly more potent than the aqueous AR extract; however, it did not affect the expression of phospho-Akt or phospho-mTOR. In conclusion, the AR aqueous extract possessed antioxidant and neuroprotective properties against 6-OHDA-induced toxicity in SH-SY5Y cells. The mechanism of action involves the upregulation of the Akt/mTOR and MEK/ERK-dependent pathways. These findings indicate the potential utility of AR and its active ingredients in preventing or treating neurodegenerative disorders associated with oxidative stress such as PD.

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Hammertoes with greater preoperative transverse plane deformity are more likely to recur after corrective surgery; however, it is unclear whether this represents an inherent (fixed, nonmodifiable) risk, or whether steps can be taken intraoperatively to mitigate this risk. In this study, we examined whether transverse plane transposition and/or shortening of the second metatarsal during second hammertoe surgery influenced recurrence. We performed a secondary analysis of pre-existing data from patients that had previously undergone second hammertoe surgery at our institution between January 1, 2011 and December 31, 2013. One hundred two patients (137 toes) were followed for a mean 28 ± 7.8 months postoperatively. Thirty-seven toes required, at the surgeon's discretion, an additional/concomitant Weil metatarsal osteotomy. Magnitude of transverse plane transposition and shortening of the second metatarsal, and joint angular measurements were obtained from the second metatarsophalangeal joint on weightbearing AP radiographs preoperatively and at 6 to 10 weeks postoperatively. Cox regression analysis was used to identify predictors of hammertoe recurrence using these new variables and a set of known predictors. In the final regression model, failure to establish a satisfactory postoperative metatarsal parabola (i.e., long second metatarsal; Nilsonne values <-4 mm, multivariate hazards ratio [HR] 1.96, p = .097), and intraoperative lateral transposition of the metatarsal head (multivariate HR 3.45, p = .028) seemed to confer additional risk for hammertoe recurrence. We conclude that shortening osteotomies may be assistive in some individuals, while further inquiry is still needed to determine whether similar benefits can be derived from medial head transposition in medial toe deformities.

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B and T lymphocyte attenuator (BTLA) is an attractive target for a new class of therapeutics that attempt to rebalance the immune system by agonizing checkpoint inhibitory receptors (CIRs). Herpesvirus entry mediator (HVEM) binds BTLA in both trans- and cis-orientations. We report here the development and structural characterization of three humanized BTLA agonist antibodies, 22B3, 25F7, and 23C8. We determined the crystal structures of the antibody-BTLA complexes, showing that these antibodies bind distinct and non-overlapping epitopes of BTLA. While all three antibodies activate BTLA, 22B3 mimics HVEM binding to BTLA and shows the strongest agonistic activity in functional cell assays and in an imiquimod-induced mouse model of psoriasis. 22B3 is also capable of modulating HVEM signaling through the BTLA-HVEM cis-interaction. The data obtained from crystal structures, biochemical assays, and functional studies provide a mechanistic model of HVEM and BTLA organization on the cell surface and informed the discovery of a highly active BTLA agonist.

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Dopamine (DA) loss in Parkinson's disease (PD) causes debilitating motor deficits. However, dopamine is also widely linked to reward prediction and learning, and the contribution of dopamine-dependent learning to movements that are impaired in PD-which often do not lead to explicit rewards-is unclear. Here, we used two distinct motor tasks to dissociate dopamine's acute motoric effects vs. its long-lasting, learning-mediated effects. In dopamine-depleted mice, motor task performance gradually worsened with task exposure. Task experience was critical, as mice that remained in the home cage during the same period were relatively unimpaired when subsequently probed on the task. Repeated dopamine replacement treatments acutely rescued deficits and gradually induced long-term rescue that persisted despite treatment withdrawal. Surprisingly, both long-term rescue and parkinsonian performance decline were task specific, implicating dopamine-dependent learning. D1R activation potently induced acute rescue that gradually consolidated into long-term rescue. Conversely, reduced D2R activation potently induced parkinsonian decline. In dopamine-depleted mice, either D1R activation or D2R activation prevented parkinsonian decline, and both restored balanced activation of direct vs. indirect striatal pathways. These findings suggest that reinforcement and maintenance of movements-even movements not leading to explicit rewards-are fundamental functions of dopamine and provide potential mechanisms for the hitherto unexplained "long-duration response" by dopaminergic therapies in PD.

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Therapeutic release from hydrogels is traditionally controlled by encapsulation within nanoparticles; however, this strategy is limited for the release of proteins due to poor efficiency and denaturation. To overcome this problem, we designed an encapsulation-free release platform where negatively charged proteins are adsorbed to the exterior of transiently cationic nanoparticles, thus allowing the nanoparticles to be formulated separately from the proteins. Release is then governed by the change in nanoparticle surface charge from positive to neutral. To achieve this, we synthesized eight zwitterionic poly(lactide-block-carboxybetaine) copolymer derivatives and formulated them into nanoparticles with differing surface chemistry. The nanoparticles were colloidally stable and lost positive charge at rates dependent on the hydrolytic stability of their surface ester groups. The nanoparticles (NPs) were dispersed in a physically cross-linked hyaluronan-based hydrogel with one of three negatively charged proteins (transferrin, panitumumab, or granulocyte-macrophage colony-stimulating factor) to assess their ability to control release. For all three proteins, dispersing NPs within the gels resulted in significant attenuation of release, with the extent modulated by the hydrolytic stability of the surface groups. Release was rapid from fast-hydrolyzing ester groups, reduced with slow-hydrolyzing bulky ester groups, and very slow with nonhydrolyzing amide groups. When positively charged lysozyme was loaded into the nanocomposite gel, there was no significant attenuation of release compared to gel alone. These data demonstrate that electrostatic interactions between the protein and NP are the primary driver of protein release from the hydrogel. All released proteins retained bioactivity as determined with in vitro cell assays. This release strategy shows tremendous versatility and provides a promising new platform for controlled release of anionic protein therapeutics.

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Keratinocytes form the physical barrier of the skin and play an important role in the inflammatory process. Amauroderma rugosum is an edible mushroom; however, its pharmacological properties have seldom been studied. Although the anti-inflammatory effect of the organic solvent extract of Amauroderma rugosum has been previously reported, it is not known whether the aqueous extract has a similar effect. In addition, the effect of Amauorderma rugosum extract on skin has never been explored. Therefore, the objectives of the present study were to evaluate the anti-inflammatory effects of the aqueous extract of Amauroderma rugosum on HaCaT keratinocytes, to explore its mechanisms of action, and to study the possible active ingredients involved. The results showed that the aqueous extract of Amauroderm rugosum at a concentration of 1.5 mg/mL was non-toxic to HaCaT cells and inhibited the release of cytokine interleukin-1ß, and chemokines interleukin-8 and monocyte chemoattractant protein-1 in tumor necrosis factor (TNF)-α- and interferon (IFN)-γ-stimulated HaCaT cells. Amauroderma rugosum extract reduced the intracellular levels of reactive oxygen species. In addition, Amauroderma rugosum extract reduced the total protein expression of nuclear factor-kappa B (NF-κB) and B-cells inhibitor alpha in HaCaT keratinocytes and inhibited the phosphorylation of mitogen-activated protein kinase kinase (MEK) 1/2, extracellular signal-regulated kinase (ERK) 1/2, protein kinase B (Akt), and mammalian target of rapamycin (mTOR) in TNF-α- and INF-γ-stimulated HaCaT keratinocytes. Chemical analysis revealed that the aqueous extract of Amauroderma rugosum contains polysaccharides, triterpenes, and phenolic compounds. Anti-inflammatory compounds, such as gallic acid, guanosine, and uridine, were also present. The anti-inflammatory effect of Amauroderma rugosum could be mimicked by a combination of gallic acid, guanosine, and uridine. In conclusion, our study suggests that the aqueous extract of Amauroderma rugosum exerts anti-inflammatory effects on keratinocytes through its antioxidant and inhibitory effects on MEK/ERK-, Akt/mTOR-, and NF-κB-dependent signaling pathways.

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The increasing prevalence of diabatic foot ulcers (DFUs) is not only costly, but carries a large mortality burden. In this article, we discuss important traditional concepts in the management of DFUs and elaborate on how new technologies have expanded our ability to treat DFUs effectively. New supplies and wound care products have been developed to target the following traditional areas of focus: tissue, infection/inflammation, moisture, and edge. Offloading strategies have grown from standard orthotics or insoles to total contact casting and three-dimensional-printed orthotics to produce the optimum material stiffness for each patient. The concepts of pressure and temperature monitoring have led to the development of multiple devices that transmit continuous monitoring in real time, giving a dynamic picture of plantar stress and training patients in new walking strategies for self-offloading. Surgical approaches have also evolved from the classic surgical debridement and correcting deformities that cause friction to creation of acellular and bio-printed cellular skin substitutes that can be used for grafting. Surveillance and long-term follow-up with a multidisciplinary team have also changed in the face of smartphones and watches that allow patients to monitor themselves in real time with daily prompts and reminders to shape desired behaviors in between clinic visits. Modern technology is changing management of DFUs by expanding on traditional concepts and improving standard therapies.

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Clinical outcomes for doxorubicin (Dox) are limited by its cardiotoxicity but a combination of Dox and agents with cardioprotective activities is an effective strategy to improve its therapeutic outcome. Natural products provide abundant resources to search for novel cardioprotective agents. Ganoderma lucidum (GL) is the most well-known edible mushroom within the Ganodermataceae family. It is commonly used in traditional Chinese medicine or as a healthcare product. Amauroderma rugosum (AR) is another genus of mushroom from the Ganodermataceae family, but its pharmacological activity and medicinal value have rarely been reported. In the present study, the cardioprotective effects of the AR water extract against Dox-induced cardiotoxicity were studied in vitro and in vivo. Results showed that both the AR and GL extracts could potentiate the anticancer effect of Dox. The AR extract significantly decreased the oxidative stress, mitochondrial dysfunction, and apoptosis seen in Dox-treated H9c2 rat cardiomyocytes. However, knockdown of Nrf2 by siRNA abolished the protective effects of AR in these cells. In addition, Dox upregulated the expression of proapoptotic proteins and downregulated the Akt/mTOR and Nrf2/HO-1 signaling pathways, and these effects could be reversed by the AR extract. Consistently, the AR extract significantly prolonged survival time, reversed weight loss, and reduced cardiac dysfunction in Dox-treated mice. In addition, oxidative stress and apoptosis were suppressed, while Nrf2 and HO-1 expressions were elevated in the heart tissues of Dox-treated mice after treatment with the AR extract. However, the GL extract had less cardioprotective effect against Dox in both the cell and animal models. In conclusion, the AR water extract demonstrated a remarkable cardioprotective effect against Dox-induced cardiotoxicity. One of the possible mechanisms for this effect was the upregulation of the mTOR/Akt and Nrf2/HO-1-dependent pathways, which may reduce oxidative stress, mitochondrial dysfunction, and cardiomyocyte apoptosis. These findings suggested that AR may be beneficial for the heart, especially in patients receiving Dox-based chemotherapy.

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Amauroderma rugosum (AR) is a basidiomycete in the Ganodermataceae family that has been used traditionally to prevent epileptic attacks and constant crying in babies. However, AR has not been widely studied scientifically. In this review, we summarize the phytochemical components and pharmacological properties of AR that have been reported in the literature. Chemical analyses have revealed that the components of AR include sterols, flavonoids, fatty acids and esters, aromatic acids and esters, phenols, polysaccharides, and triterpenes. Pharmacological properties of AR include antioxidant, anti-inflammatory, neuroprotective, anti-cancer, anti-hyperlipidemic, anti-epileptic, and antibacterial effects. These findings suggest that AR and its bioactive ingredients have potential therapeutic applications, particularly for age-related diseases.

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We report the prevalence of reduced levels of carbon monoxide transfer factor (TLCO) in middle-aged current or ex-smokers with normal spirometry. Spirometry and TLCO measurements were performed and we identified 391 subjects aged 40-60 years, with a significant smoking history and normal spirometry. In this group, 96 subjects (24%) had TLCO measuremements below the lower limit of normal when using the newly established Global Lung Initiative (GLI) reference equations. The measurement of TLCO should be considered as part of the standard assessment of smokers.

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Amauroderma rugosum (AR) is a dietary mushroom in the Ganodermataceae family whose pharmacological activity and medicinal value have rarely been reported. In this study, the antioxidant capacity and neuroprotective effects of AR were investigated. The aqueous extract of AR was confirmed to contain phenolic compounds, polysaccharides, and triterpenes. The results of 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and total antioxidant capacity assays revealed that AR extract scavenged reactive oxygen species. Moreover, AR extract decreased the cytotoxicity, oxidative stress, mitochondrial dysfunction, and apoptosis of PC12 cells induced by 6-hydroxydopamine (6-OHDA). In addition, 6-OHDA upregulated the expressions of proapoptotic proteins and downregulated the Akt (protein kinase B)/mTOR- (mammalian target of rapamycin-) and MEK (mitogen-activated protein kinase kinase)/ERK- (extracellular signal-regulated kinases-) dependent signaling pathways. These effects of 6-OHDA were abolished or partially reversed by AR extract. Furthermore, the neuroprotective effects of AR in 6-OHDA-treated PC12 cells were significantly abolished by Akt and MEK inhibitor. Thus, AR extract possesses neuroprotective effects, probably through its antioxidant and antiapoptotic effects. These findings suggest the potential application of AR in the prevention or treatment of oxidative stress-related neurodegenerative diseases such as Parkinson's disease.

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Changes in striatal cholinergic interneuron (ChI) activity are thought to contribute to Parkinson's disease pathophysiology and dyskinesia from chronic L-3,4-dihydroxyphenylalanine (L-DOPA) treatment, but the physiological basis of these changes is unknown. We find that dopamine lesion decreases the spontaneous firing rate of ChIs, whereas chronic treatment with L-DOPA of lesioned mice increases baseline ChI firing rates to levels beyond normal activity. The effect of dopamine loss on ChIs was due to decreased currents of both hyperpolarization-activated cyclic nucleotide-gated (HCN) and small conductance calcium-activated potassium (SK) channels. L-DOPA reinstatement of dopamine normalized HCN activity, but SK current remained depressed. Pharmacological blockade of HCN and SK activities mimicked changes in firing, confirming that these channels are responsible for the molecular adaptation of ChIs to dopamine loss and chronic L-DOPA treatment. These findings suggest that targeting ChIs with channel-specific modulators may provide therapeutic approaches for alleviating L-DOPA-induced dyskinesia in PD patients.

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Ion channels are present at specific levels within subcellular compartments of excitable cells. The regulation of ion channel trafficking and targeting is an effective way to control cell excitability. The BK channel is a calcium-activated potassium channel that serves as a negative feedback mechanism at presynaptic axon terminals and sites of muscle excitation. The C. elegans BK channel ortholog, SLO-1, requires an endoplasmic reticulum (ER) membrane protein for efficient anterograde transport to these locations. Here, we found that, in the absence of this ER membrane protein, SLO-1 channels that are seemingly normally folded and expressed at physiological levels undergo SEL-11/HRD1-mediated ER-associated degradation (ERAD). This SLO-1 degradation is also indirectly regulated by a SKN-1A/NRF1-mediated transcriptional mechanism that controls proteasome levels. Therefore, our data indicate that SLO-1 channel density is regulated by the competitive balance between the efficiency of ER trafficking machinery and the capacity of ERAD.

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Offloading the diabetic foot remains the major consideration for ulceration prevention and healing. This narrative literature review presents a brief overview of current guidelines for offloading the diabetic foot and discusses the implications that come with offloading treatment modalities and their effects on the kinetic chain of the lower extremity. We also present the latest innovative studies from the Dr. William M. Scholl College of Podiatric Medicine at Rosalind Franklin University of Medicine and Science that advance the knowledge in this field and provide avenues for future research opportunities.

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Lower extremity biomechanics is the cornerstone of podiatric medicine and surgery. The foot and ankle act as the interface between the ground and proximal segments, mediating internal and external moments Although the medial longitudinal arch has been widely researched, the details of the lateral longitudinal arch are less extensively delineated. The purpose of this review is to analyze the biomechanics of the lateral column as it relates to lower extremity biomechanics and function.

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In-house prepared graphene oxide (GO) was processed via base washing, sonication, cleaning and combinations of these processing techniques to evaluate the impact on the flake morphology, composition and cytotoxicity of the material. The flakes of unprocessed GO were relatively planar, but upon base washing, the flakes became textured exhibiting many folds and creases observed by AFM. In addition to the pronounced effect on the topography, base washing increased the C/O ratio and increased the cytotoxicity of GO on all four cell lines studied determined via the WST-8 assay. Sonicating the unprocessed and base washed samples resulted in smaller flakes with a similar topography; the base washed flakes lost the texture previously observed upon sonication. The sonicated samples were more toxic than the unprocessed sample, attributed to the smaller flake size, but were interestingly less toxic than the base washed, unsonicated sample despite the base washed unsonicated sample having a larger flake size. This unexpected finding was confirmed by a second analyst using the same, and a different source of GO and resulted in the conclusion that the morphology of GO greatly impacts the cytotoxicity. Cleaning the GO reduced the amount of nitrogen and sulfur impurities in the sample but had no significant impact on the cytotoxicity of the material. It was observed that nutrient depletion via nanomaterial adsorption was not the route of cytotoxicity for the GO samples studied.

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As boron nitride nanotubes (BNNTs) find increased use in numerous applications, potential adverse health effects of BNNT exposure are a growing concern. Current in vitro cytotoxicity studies on BNNTs are inconsistent and even contradictory, likely due to the lack of reference materials, standardized characterization methods and measurement protocols. New approaches, particularly with the potential to reliably relate in vitro to in vivo studies, are critically needed. This work introduces a novel atomic force microscopy (AFM)-based cardiomyocyte assay that reliably assesses the cytotoxicity of a well-characterized boron nitride nanotube reference material, code named BNNT-1. High energy probe sonication was used to modify and control the length of BNNT-1. The polymer polyethylenimine (PEI) was used concurrently with sonication to produce stable, aqueous dispersions of BNNT-1. These dispersions were used to perform a systematic analysis on both the length and height of BNNT-1 via a correlated characterization approach of dynamic light scattering (DLS) and AFM. Cytotoxicity studies using the novel cardiomyocyte AFM model were in agreement with traditional colorimetric cell metabolic assays, both revealing a correlation between tube length and cytotoxicity with longer tubes having higher cytotoxicity. In addition to the size-dependent cytotoxicity, it was found that BNNT-1 exhibits concentration and cell-line dependent cytotoxic effects.

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OBJECTIVE: This case series evaluates the outcomes of persons with chronic lower extremity wounds treated with an esterified hyaluronic acid matrix (EHAM). MATERIALS AND METHODS: Data were abstracted from 12 consecutive patients with a total of 14 evaluated chronic wounds (12 [100%] men, mean age 58.72 years) presenting for care at a multidisciplinary wound care center. Nine of the 12 patients had diabetes. The mean wound duration was 39.2 weeks. All patients received surgical wound debridement and were started on therapy consisting of weekly to biweekly applications of the EHAM with a nonadherent, moisture-retentive dressing until complete epithelialization was achieved. Outcomes evaluated included time to complete wound closure and proportion of patients achieving wound closure in 20 weeks. RESULTS: In total, 85.7% of wounds measuring a mean of 2.32 cm2 healed in the 20-week evaluation period. Of those that healed, healing took place in a mean of 8.9 weeks. CONCLUSIONS: A regimen of moist wound healing using an EHAM, which provides a scaffold for in-growing cells, may be a useful adjunct in the treatment of chronic, noninfected, nonischemic wounds.

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