The hypothesis of 'biophysical matrix contraction': wound contraction revisited

Combination of secondary intention healing and primary closure to reconstruct large facial defects

Secondary intention healing has been a well-established method to close wounds for more than 200 years. Indeed, it represents the easiest technique in the ladder of plastic reconstruction. Primary wound closure (side-to-side closure, direct wound closure) is the second easiest method. The combination of these two techniques is already an integral aspect of specific surgical procedures, e.g. the reconstruction of the donor site of a paramedian forehead flap. This minireview will show that the combination is also a suitable alternative to classic flaps in reconstruction of different aesthetic subunits of the face. These are the scalp, the lateral cheek, the upper nasal sidewall/medial canthus and the retroauricular region. The advantages and disadvantages will be discussed and illustrated with clinical examples.

V-EMF therapy: A new painless and completely non-invasive treatment for striae gravidarum

BACKGROUND

The appearance of striae gravidarum (SG) during pregnancy is a common problem. The most common SG are abdominal striae, which can cause the greatest sequelae after pregnancy, and in the long term. There are several solutions to prevent and treat these striae, but not all are completely effective, and not without side effects.

AIMS

The aim of this study was to evaluate the effectiveness of a treatment that applies an electromagnetic field under vacuum (V-EMF therapy) on the abdominal SG.

METHODS

A retrospective analysis was conducted on the medical records of 26 women affected by abdominal SG and treated with V-EMF therapy. The results were evaluated using two different 5-point Likert Scales: one administered to the treated subjects to evaluate their satisfaction, and one to the doctors who performed the treatment, to evaluate the improvement of the striae. The presence of side effects, and the effects of sun exposure after treatment were also considered.

RESULTS

Only two treated subjects rated their level of satisfaction with a Score III on the Liker Scale. Everyone else expressed higher levels of satisfaction. Only one doctor rated the improvement of the striae with a Liker scale score of III. All the others reported greater improvements. No discomfort or side effects were noted either during the individual treatment sessions, or at the end of the treatment. The striae showed a newfound ability to tan.

CONCLUSIONS

V-EMF therapy proves to be a valid, safe, and effective treatment modality for SG.

Immune Mechanisms of Pulmonary Fibrosis with Bleomycin

Fibrosis and structural remodeling of the lung tissue can significantly impair lung function, often with fatal consequences. The etiology of pulmonary fibrosis (PF) is diverse and includes different triggers such as allergens, chemicals, radiation, and environmental particles. However, the cause of idiopathic PF (IPF), one of the most common forms of PF, remains unknown. Experimental models have been developed to study the mechanisms of PF, and the murine bleomycin (BLM) model has received the most attention. Epithelial injury, inflammation, epithelial-mesenchymal transition (EMT), myofibroblast activation, and repeated tissue injury are important initiators of fibrosis. In this review, we examined the common mechanisms of lung wound-healing responses after BLM-induced lung injury as well as the pathogenesis of the most common PF. A three-stage model of wound repair involving injury, inflammation, and repair is outlined. Dysregulation of one or more of these three phases has been reported in many cases of PF. We reviewed the literature investigating PF pathogenesis, and the role of cytokines, chemokines, growth factors, and matrix feeding in an animal model of BLM-induced PF.

Vacuum and Electromagnetic Fields Treatment to Regenerate a Diffuse Mature Facial Scar Caused by Sulfuric Acid Assault

Acid attacks are on the rise, and they cause extensive and deep burns, especially on the face. The treatments used to improve the aesthetic, functional and social impact of non-acid scars do not always prove useful for acid scars. This article reports the case of a woman with an extended, mature, acid facial scar, caused by sulfuric acid assault, treated with a recent new procedure that combines the application of vacuum and electromagnetic fields. Before and after the treatment, the aesthetic appearance, and motor function of the face and neck were evaluated, as well as the level of hydration, the amount of sebum, the elasticity, and the pH of the skin. The improvements highlighted after the treatment of the aesthetic and functional characteristics of the face and neck, and of the physical parameters of the skin seemed to indicate that this particular treatment induces tissue regeneration, even in the nerve component. However, it is evident that the rehabilitation pathways of facial wounds and scars must be personalized, and must include continuous psychological support for the patient.

Bioelectric fields coordinate wound contraction and re-epithelialization process to accelerate wound healing via promoting myofibroblast transformation

Electric fields (EFs) are thought to play a decisive role in wound healing. However, most studies focused on the effects of EF on single species of cells in vitro. Here, we aimed to investigate the coordination function of EFs on wound healing. Using a bamamini pig whole-layer wound model, we further evaluated the potential of EFs as a treatment modality by applying continuous and stable EF to the wound, and we found that EF promoted wound contraction and re-epithelialization in vivo, which accelerated wound healing. In vitro, we found that EFs significantly promoted the collective migration of HaCaT cells, guided HSF cells rearrangement, and promoted collagen secretion and myofibroblast transformation, and the electrotaxis of HaCaT cells was significantly enhanced on the collagen substrate and F-actin polarization at the leading edge of the cells was more pronounced. Overall, we determined that EF promotes wound contraction by promoting myofibrillar transformation, while accelerating the formation of collagen substrates, and the substrates could provide a good basis for electric field-guided re-epithelialization. EF may promote wound healing in multiple dimensions interaction and coordinate the whole process of wound healing. These findings provide support for the continued development of EF for wound treatment applications.

Leveraging Potential of Nanotherapeutics in Management of Diabetic Foot Ulcer

Diabetic foot ulcers (DFUs) are the most common complications associated with diabetes mellitus. DFUs are displayed as open sores or wounds located on the bottom of the foot as a secondary complication of diabetes mellitus (DM). DFUs are associated with significant morbidity and mortality and can subsequently lead to hospitalization and lower limb amputation if not recognized and treated on time. An immense challenge to conventional treatments is caused by the chronic nature of diabetic foot syndrome and it has led to the emergence of nanotechnology-based therapeutics. The greatest advantages of these nanotherapeutics are their unique biological, chemical, and physical properties. The present review highlights the augmentation of bacterial infections relating to delayed healing of DFUs and the potential of nanotherapeutics such as polymeric nanoparticles, metallic nanoparticles, siRNA-based nanoparticles, lipid nanoparticles, and nanofibers in accelerating wound healing in diabetic foot ulcers.

Role of an acidic environment in the treatment of diabetic foot infections: A review

Management of diabetic foot ulcers is the biggest challenge to the clinician, as conventional antibiotic therapies and local wound care have their own limitations. They are not effective for control of infections and promotion of healing because of cytotoxic effects. In view of cytotoxicity of routinely used topical antiseptic agents, this article focuses on the search of an ideal topical antiseptic agent that is safe and effective in controlling infectious agents and also in promoting the healing process. This review focuses on the use of various acids such as citric, acetic, hyaluronic, and hypochlorous acids as topical agents in diabetic foot infections. This article also focuses on the different roles of acids in the treatment of diabetic foot infections.

Fibrinogen, collagen, and transferrin adsorption to poly(3,4-ethylenedioxythiophene)-xylorhamno-uronic glycan composite conducting polymer biomaterials for wound healing applications

We present the conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT) doped with an algal-derived glycan extract, Phycotrix™ [xylorhamno-uronic glycan (XRU84)], as an innovative electrically conductive material capable of providing beneficial biological and electrical cues for the promotion of favorable wound healing processes. Increased loading of the algal XRU84 into PEDOT resulted in a reduced surface nanoroughness and interfacial surface area and an increased static water contact angle. PEDOT-XRU84 films demonstrated good electrical stability and charge storage capacity and a reduced impedance relative to the control gold electrode. A quartz crystal microbalance with dissipation monitoring study of protein adsorption (transferrin, fibrinogen, and collagen) showed that collagen adsorption increased significantly with increased XRU84 loading, while transferrin adsorption was significantly reduced. The viscoelastic properties of adsorbed protein, characterized using the ΔD/Δf ratio, showed that for transferrin and fibrinogen, a rigid, dehydrated layer was formed at low XRU84 loadings. Cell studies using human dermal fibroblasts demonstrated excellent cell viability, with fluorescent staining of the cell cytoskeleton illustrating all polymers to present excellent cell adhesion and spreading after 24 h.

Preliminary screening of the aqueous extracts of twenty-three different seaweed species in Sri Lanka with in-vitro and in-vivo assays

Background

Seaweeds are an important source of bioactive compounds which are applied in various aspects of medicinal investigations. The present study was conducted to investigate cytoxicity (in-vitro and in-vivo) and wound healing activity of different seaweed species in Sri Lanka.

Methods

Twenty-three seaweed samples, belonging to Phaeophyta (Brown), Chlorophyta (Green) and Rhodophyta (Red) were used for the experiments. Samples were collected from the inter-tidal and the sub-tidal habitats around Sri Lankan coast (Southern, Northern and North-western). Aqueous seaweed extracts were tested for cytotoxic and wound healing activity; in-vitro and in-vivo. To determine toxicity of aqueous seaweed extracts, brine shrimp lethality assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay on mouse fibroblasts (L929) cell line were performed. Cell migration induction of seaweed extracts was assessed by scratch wound healing assay using L929 cell line. Based on the our previous experiments S.ilicifolium (SW23) was selected for the in vivo study to confirm our hypothesis. Albino mice (BALB/c) were divided into three groups (12 in each) and a circular area (44.07 ± 02.51 mm²) of full skin was excised to create a wound in mice group II and III. Group III received aqueous extract of Sargasum illicifolium (400 mg/kg BW/day for 12 days, orally), Group II received distilled water for 12 days whereas Group I was used as the control group and it was tested without forming wounds and without providing any treatment. Further, the expression level of Tumor Necrosis Factor (TNF-α) and Transforming Growth Factor-β (TGF-β) via RT-PCR were measured every three days until the end of the experiment.

Results

Phytochemical tests showed positive results to flavonoids in all the selected green seaweeds and alkaloids were observed in red seaweeds. In the toxicity assay, red seaweed, Acanthophora spicifera (SW17) was found to be highly effective on nauplii of brine shrimp (LC₅₀ = 0.072 μg/μl). LC₅₀ value of green seaweed species, Caulerpa racemosa (SW02 and SW08) and Caulerpa sertularioides (SW10) was not found within the tested concentration series. The highest cytotoxic effect on L929 cell line was exhibited by aqueous extracts of red seaweed; Jania adhaereus with 50.70 ± 7.304% cell viability compared with control group. The highest cell migration activity was observed in L929 cell line group treated with extracts of green seaweed namely; Halimeda opuntin (SW07) and extracts of brown seaweed namely; Stoechospermum polypodioides (SW11). Extracts of S. illicifolium (SW23) exhibited a significantly enhanced wound healing activity in mice group III within three days (P < 0.05) with an open wound area of 17.35 ± 1.94 mm² compared with control group (26.29 ± 2.42 mm²). TGF-β gene expression peaked on 6^th day of post-wound and subsequently decreased on 9^th day of post-wound in mice group III. TNF-α expression was suppressed in mice group III whereas it was elevated in group II. TGF-β expression is enhanced in the treatment group compared to the control group.

Conclusions

Aqueous extracts of selected seaweeds are a significant source of potential compounds with wound healing properties, which might be helpful in the healing of various wounds. This also infers that many species of brown and red seaweeds have the potential of wound healing, specifically, Sargasum illicifolium and Jania adhaereus could be a potential candidate for in-vivo studies related to wound healing and cancer therapy in the near future.

Inflammatory cytokines and matrix metalloproteinases in the synovial fluid after intra-articular elbow fracture

BACKGROUND AND HYPOTHESIS

Post-traumatic elbow contracture remains a common and challenging complication with often unsatisfactory outcomes. Although the etiology is unknown, elevated or abnormal post-fracture synovial fluid cytokine levels may result in the migration of fibroblasts to the capsule and contribute to capsular pathology. Thus, the purpose of this study was to characterize the cytokine composition in the synovial fluid fracture hematoma of patients with intra-articular elbow fractures.

METHODS

The elbow synovial fluid fracture hematoma of 11 patients with intra-articular elbow fractures was analyzed for CTXII (C-terminal telopeptides of type II collagen [a cartilage breakdown product]) as well as 15 cytokines and matrix metalloproteinases (MMPs) including interferon γ, interleukin (IL) 1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumor necrosis factor α, MMP-1, MMP-2, MMP-3, MMP-9, and MMP-10. The uninjured, contralateral elbow served as a matched control. Mean concentrations of each factor were compared between the fluid from fractured elbows and the fluid from control elbows.

RESULTS

The levels of 14 of 15 measured cytokines and MMPs-interferon γ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumor necrosis factor α, MMP-1, MMP-3, MMP-9, and MMP-10-were significantly higher in the fractured elbows. In addition, post hoc power analysis revealed that 10 of 14 significant differences were detected with greater than 90% power. The mean concentration of CTXII was not significantly different between groups.

CONCLUSIONS

These results demonstrate a proinflammatory environment after fracture that may be the catalyst to the development of post-traumatic elbow joint contracture. The cytokines with elevated levels were similar, although not identical, to the cytokines with elevated levels in studies of other weight-bearing joints, indicating the elbow responds uniquely to trauma.

Effect of 632 nm He-Ne Laser on Gram-Positive Bacteria in Deep Partial Thickness Pediatric Burn: A Prospective Double-Blind Randomized Controlled Trial

Background. Burns are one of the most common injuries in pediatric population, gram-positive bacteria is the main pathogens responsible for wound infection that is the leading cause of morbidity and sometimes mortality in growing children with burn. Low level laser is a new treatment option that is increasingly used in the field of wound healing. Aim. To investigate the effect of He-Ne laser on gram-positive bacteria and healing time of deep second-degree pediatric burn. Methods. Thirty children of both genders aged from 2 to 9 years old with 2nd degree upper limb burn infected with gram-positive bacteria participated in this study. They were randomly assigned into two equal groups; either the control group (group A) received systematic antibiotic and 10 minutes’ placebo laser light, or the laser group (group B) received 632 nm laser light, 6 J/cm2 scanning technique for 10 minutes. All patients received regular wound care (dressing). The study protocol was once a day, 3 times / week for one month. Pre and post-treatment evaluation of wound culture and the healing time was recorded for both groups. Results. Wound culture of all children in both groups were negative after two weeks of the study and wound healing time was significantly shorter in the laser group (14.6±5.7 days) than the control group (27±7.3 days). Conclusion. He-Ne laser is an effective option of treatment for 2nd-degree pediatric burn as it has a bactericidal effect on gram-positive bacteria and accelerates wound healing process significantly.

Bioengineered Platforms for Chronic Wound Infection Studies: How Can We Make Them More Human-Relevant?

Chronic wound infections are an important cause of delayed wound healing, posing a significant healthcare burden with consequences that include hospitalization, amputation, and death. These infections most often take the form of three-dimensional biofilm communities, which are notoriously recalcitrant to antibiotics and immune clearance, contributing to the chronic wound state. In the chronic wound microenvironment, microbial biofilms interact closely with other key components, including host cellular and matrix elements, immune cells, inflammatory factors, signaling components, and mechanical cues. Intricate relationships between these contributing factors not only orchestrate the development and progression of wound infections but also influence the therapeutic outcome. Current medical treatment for chronic wound infections relies heavily on long-term usage of antibiotics; however, their efficacy and reasons for failure remain uncertain. To develop effective therapeutic approaches, it is essential to better understand the complex pathophysiology of the chronic wound infection microenvironment, including dynamic interactions between various key factors. For this, it is critical to develop bioengineered platforms or model systems that not only include key components of the chronic wound infection microenvironment but also recapitulate interactions between these factors, thereby simulating the infection state. In doing so, these platforms will enable the testing of novel therapeutics, alone and in combinations, providing insights toward composite treatment strategies. In the first section of this review, we discuss the key components and interactions in the chronic wound infection microenvironment, which would be critical to recapitulate in a bioengineered platform. In the next section, we summarize the key features and relevance of current bioengineered chronic wound infection platforms. These are categorized and discussed based on the microenvironmental components included and their ability to recapitulate the architecture, interactions, and outcomes of the infection microenvironment. While these platforms have advanced our understanding of the underlying pathophysiology of chronic wound infections and provided insights into therapeutics, they possess certain insufficiencies that limit their clinical relevance. In the final section, we propose approaches that can be incorporated into these existing model systems or developed into future platforms developed, thus enhancing their biomimetic and translational capabilities, and thereby their human-relevance.

Scarless wound healing: From development to senescence

An essential element of tissue homeostasis is the response to injuries, cutaneous wound healing being the most studied example. In the adults, wound healing aims at quickly restoring the barrier function of the skin, leading however to scar, a dysfunctional fibrotic tissue. On the other hand, in fetuses a scarless tissue regeneration takes place. During ageing, the wound healing capacity declines; however, in the absence of comorbidities a higher quality in tissue repair is observed. Senescent cells have been found to accumulate in chronic unhealed wounds, but more recent reports indicate that their transient presence may be beneficial for tissue repair. In this review data on skin wound healing and scarring are presented, covering the whole spectrum from early embryonic development to adulthood, and furthermore until ageing of the organism.

Comparison of contraction rates of epigastric and extended dorsal island skin flaps in rats

Flap surgery is a wide field in plastic and reconstructive surgery practice and experimental research is needed to improve surgical success. These research is often performed on rats. Rat is a loose-skinned animal and contraction of skin flaps on rats is an underestimated condition. Besides this variable contraction of survived and necrotic tissues may mislead calculations and results. In this study, contraction patterns of epigastric and dorsal island skin flaps were investigated to identify this phenomenon. Forty-two male Sprague-Dawley rats were divided into four groups. Eleven epigastric flaps with unilateral pedicles, 11 epigastric flaps with bilateral pedicles, 10 extended dorsal island skin flaps with unilateral pedicles, and 10 extended dorsal island skin flaps with bilateral pedicles were prepared. Total, necrotic and viable flap areas were calculated from standardized photographs which were taken daily. The animals were placed on marked papers and image processing software was used the calculate flap areas from the photographs. Respect to these daily flap areas, the contraction rates in epigastric flaps were highly significant. The area loss in necrotic tissues were faster than the viable areas. Compared to the epigastric flaps, the contraction was not significant in extended dorsal island skin flaps flap groups. In conclusion, the rat extended dorsal island skin flap is a more reliable model for experimental flap research, which is resistant to contraction, when compared to the epigastric skin flap model.

A Nationwide Assessment of the Emergency Department Management of Acute Urinary Retention Due to Urethral Stricture

OBJECTIVE

To evaluate the nationwide practice patterns of the management of acute urinary retention (AUR) secondary to urethral stricture (US) in an emergency department (ED) setting.

MATERIALS AND METHODS

We used the 2006-2010 Nationwide Emergency Department Sample to identify men with US who received treatment for AUR. We excluded patients with benign prostatic hyperplasia, vesicourethral anastomotic stenosis, neurogenic bladder, and bladder cancer. Primary outcome was urethral dilation or suprapubic tube (SPT) placement as initial AUR management. Patient demographics and hospital factors were also examined. Multivariate logistic regression was performed to examine factors associated with initial AUR management.

RESULTS

We identified 4794 weighted ED encounters of men with US who underwent urethral dilation or SPT placement for AUR. Mean age was 58.6 ± 0.8 years. A total of 4084 (85%) men received urethral dilation, whereas 710 had SPT (15%) placement. In bivariate analysis, patients who received SPT were likely to be younger (P <.001), treated in recent years (P = .002), and in hospitals in the West region (P = .003). In multivariate analysis, SPT placement was significantly associated with younger age (P = .004), public insurance (P = .03), recent treatment years (P = .02), and hospitals in the West region (P = .02). Income and hospital teaching status did not have significant association with initial treatment choice.

CONCLUSION

Urethral dilation remains the most common urologic intervention in the ED for AUR due to US; however, there is an increasing trend toward SPT placement. Patients who are younger, publicly insured, or who receive care in the West region are more likely to receive a SPT for initial treatment of AUR due to US.

Mechanics of Wound Closure: Emerging Tape-Based Wound Closure Technology vs. Traditional Methods

To date, there is still a lack of understanding of how wound closure methods perform comparatively under daily bodily movement during the course of healing and how they affect the mechanics of healing. The present study is a first step in understanding and objectively quantifying the gap. The study provides both a new method of metrology for noninvasive evaluation of skin mechanics at the onset of wound healing and an emerging tape-based wound closure technology. The latter shows better performance with respect to commonly used staples and sutures, holding the wound intact and providing uniform mechanical support across the incision.

A unifying neuro-fasciagenic model of somatic dysfunction - underlying mechanisms and treatment - Part I

This paper offers an extensive review of the main fascia-mediated mechanisms underlying various dysfunctional and pathophysiological processes of clinical relevance for manual therapy. The concept of somatic dysfunction is revisited in light of the diverse fascial influences that may come into play in its genesis and maintenance. A change in perspective is thus proposed: from a nociceptive model that for decades has viewed somatic dysfunction as a neurologically-mediated phenomenon, to a unifying fascial model that integrates neural influences into a multifactorial and multidimensional interpretation of dysfunctional process as being partially, if not entirely, mediated by the fascia.

Choice of wound care in diabetic foot ulcer: A practical approach

Diabetic foot ulcers are the consequence of multiple factors including peripheral neuropathy, decreased blood supply, high plantar pressures, etc., and pose a significant risk for morbidity, limb loss and mortality. The critical aspects of the wound healing mechanism and host physiological status in patients with diabetes necessitate the selection of an appropriate treatment strategy based on the complexity and type of wound. In addition to systemic antibiotics and surgical intervention, wound care is considered to be an important component of diabetic foot ulcer management. This article will focus on the use of different wound care materials in diabetic foot. From a clinical perspective, it is important to decide on the wound care material depending on the type and grade of the ulcer. This article will also provide clinicians with a simple approach to the choice of wound care materials in diabetic foot ulcer.

In vivo and ex vivo approaches to studying the biomechanical properties of healing wounds in rat skin

An evaluation of wound mechanics is crucial in reflecting the wound healing status. The present study examined the biomechanical properties of healing rat skin wounds in vivo and ex vivo. Thirty male Sprague-Dawley rats, each with a 6 mm full-thickness circular punch biopsied wound at both posterior hind limbs were used. The mechanical stiffness at both the central and margins of the wound was measured repeatedly in five rats over the same wound sites to monitor the longitudinal changes over time of before wounding, and on days 0, 3, 7, 10, 14, and 21 after wounding in vivo by using an optical coherence tomography-based air-jet indentation system. Five rats were euthanized at each time point, and the biomechanical properties of the wound tissues were assessed ex vivo using a tensiometer. At the central wound bed region, the stiffness measured by the air-jet system increased significantly from day 0 (17.2%), peaked at day 7 (208.3%), and then decreased progressively until day 21 (40.2%) as compared with baseline prewounding status. The biomechanical parameters of the skin wound samples measured by the tensiometer showed a marked reduction upon wounding, then increased with time (all p &lt; 0.05). On day 21, the ultimate tensile strength of the skin wound tissue approached 50% of the normal skin; while the stiffness of tissue recovered at a faster rate, reaching 97% of its prewounded state. Our results suggested that it took less time for healing wound tissues to recover their stiffness than their maximal strength in rat skin. The stiffness of wound tissues measured by air-jet could be an indicator for monitoring wound healing and contraction.

The role of the extracellular matrix components in cutaneous wound healing

Wound healing is the physiologic response to tissue trauma proceeding as a complex pathway of biochemical reactions and cellular events, secreted growth factors, and cytokines. Extracellular matrix constituents are essential components of the wound repair phenomenon. Firstly, they create a provisional matrix, providing a structural integrity of matrix during each stage of healing process. Secondly, matrix molecules regulate cellular functions, mediate the cell-cell and cell-matrix interactions, and serve as a reservoir and modulator of cytokines and growth factors' action. Currently known mechanisms, by which extracellular matrix components modulate each stage of the process of soft tissue remodeling after injury, have been discussed.

Temporary presence of myofibroblasts in human elbow capsule after trauma

BACKGROUND

Elbow stiffness is a common complication after elbow trauma. The elbow capsule is often thickened, fibrotic, and contracted at the time of surgical release. The limited studies available suggest that the capsule is contracted because of fibroblast-to-myofibroblast differentiation. We hypothesize that myofibroblasts are absent in normal elbow capsules and in acute trauma and that they are subsequently elevated in patients with posttraumatic elbow contracture.

METHODS

We obtained twenty-one human elbow joint capsules within fourteen days after an elbow fracture and/or dislocation and thirty-four elbow joint capsules in thirty-four patients who had undergone operative release of posttraumatic contractures more than five months after injury. Myofibroblasts in the joint capsules were quantified with use of immunohistochemistry. Alpha-smooth muscle actin was used as a marker for myofibroblasts. Samples were characterized and were scored by an independent pathologist blinded for clinical data.

RESULTS

Eleven capsules were associated with the acute phase after trauma (hours to less than seven days), and staining for alpha-smooth muscle actin was negative in all but one capsule. Ten capsules were associated with a later posttraumatic phase with myofibroblasts staining positive for alpha-smooth muscle actin in all but two capsules. Thirty-two long-standing contractures showed a histological pattern consistent with chronic stages of fibrosis, characterized by increased fibroblast-like cell proliferation and higher cellular density of fibroblast-like cells with highly unstructured collagen. Two joint capsules showed an earlier phase of fibrosis. Only two of the long-standing contractures had staining of alpha-smooth muscle actin in fibroblast-like cells; the lack of staining in the other contractures suggested an absence of myofibroblasts.

CONCLUSIONS

This study presents negative results on the hypothesis that myofibroblast numbers are elevated in long-standing (more than five months) human posttraumatic elbow capsules. The absence of myofibroblasts in long-standing elbow contracture capsules is in contrast to most other studies on human tissue in the literature to date.

Calpain activity is essential in skin wound healing and contributes to scar formation

Wound healing is a multistep phenomenon that relies on complex interactions between various cell types. Calpains are ubiquitously expressed proteases regulating several processes including cellular adhesion and motility as well as inflammation and angiogenesis. Calpains can be targeted by inhibitors, and their inhibition was shown to reduce organ damage in various disease models. We aimed to assess the role of calpains in skin healing and the potential benefit of calpain inhibition on scar formation. We used a pertinent model where calpain activity is inhibited only in lesional organs, namely transgenic mice overexpressing calpastatin (CPST), a specific natural calpain inhibitor. CPST mice showed a striking delay in wound healing particularly in the initial steps compared to wild types (WT). CPST wounds displayed reduced proliferation in the epidermis and delayed re-epithelization. Granulation tissue formation was impaired in CPST mice, with a reduction in CD45+ leukocyte infiltrate and in CD31+ blood vessel density. Interestingly, wounds on WT skin grafted on CPST mice (WT/CPST) showed a similar delayed healing with reduced angiogenesis and inflammation compared to wounds on WT/WT mice demonstrating the implication of calpain activity in distant extra-cutaneous cells during wound healing. CPST wounds showed a reduction in alpha-smooth muscle actin (αSMA) expressing myofibroblasts as well as αSMA RNA expression suggesting a defect in granulation tissue contraction. At later stages of skin healing, calpain inhibition proved beneficial by reducing collagen production and wound fibrosis. In vitro, human fibroblasts exposed to calpeptin, a pan-calpain inhibitor, showed reduced collagen synthesis, impaired TGFβ-induced differentiation into αSMA-expressing myofibroblasts, and were less efficient in a collagen gel contraction assay. In conclusion, calpains are major players in granulation tissue formation. In view of their specific effects on fibroblasts a late inhibition of calpains should be considered for scar reduction.

A comparison of wound healing rate following treatment with aftamed and chlorine dioxide gels in streptozotocin-induced diabetic rats

Background and Purpose. This study aimed to evaluate the wound healing activities of Aftamed and chlorine dioxide gels in streptozotocin-induced diabetic rats. Experimental Approach. Forty-eight Sprague Dawley rats were chosen for this study, divided into 4 groups. Diabetes was induced. Two-centimeter-diameter full-thickness skin excision wounds were created. Animals were topically treated twice daily. Groups 1, the diabetic control group, were treated with 0.2 mL of sterile distilled water. Group 2 served as a reference standard were treated with 0.2 mL of Intrasite gel. Groups 3 and 4 were treated with 0.2 mL of Aftamed and 0.2 mL of chlorine dioxide gels respectively. Granulation tissue was excised on the 10th day and processed for histological and biochemical analysis. The glutathione peroxidase ,superoxide dismutase activities and the malondialdehyde (MDA) levels were determined. Results. Aftamed-treated wounds exhibited significant increases in hydroxyproline, cellular proliferation, the number of blood vessels, and the level of collagen synthesis. Aftamed induced an increase in the free radical-scavenging enzyme activity and significantly reduced the lipid peroxidation levels in the wounds as measured by the reduction in the MDA level. Conclusions. This study showed that Aftamed gel is able to significantly accelerate the process of wound healing in diabetic rats.

Clinical strategies for the alleviation of contractures from a predictive mathematical model of dermal repair

Hypertrophic scars arise when there is an overproduction of collagen during wound healing. These are often associated with poor regulation of the rate of programmed cell death (apoptosis) of the cells synthesizing the collagen or by an exuberant inflammatory response that prolongs collagen production and increases wound contraction. Severe contractures that occur, e.g., after a deep burn, can cause loss of function especially if the wound is over a joint such as the elbow or knee. Recently, we have developed a morphoelastic mathematical model for dermal repair that incorporates the chemical, cellular, and mechanical aspects of dermal wound healing. Using this model, we examine pathological scarring in dermal repair by first assuming a smaller than usual apoptotic rate for myofibroblasts, and then considering a prolonged inflammatory response, in an attempt to determine a possible optimal intervention strategy to promote normal repair, or terminate the fibrotic scarring response. Our model predicts that in both cases it is best to apply the intervention strategy early in the wound healing response. Further, the earlier an intervention is made, the less aggressive the intervention required. Finally, if intervention is conducted at a late time during healing, a significant intervention is required; however, there is a threshold concentration of the drug or therapy applied, above which minimal further improvement to wound repair is obtained.

Urethral rest: role and rationale in preparation for anterior urethroplasty

OBJECTIVES

To report the outcomes of men treated initially with a period of urethral rest to allow tissue recovery before anterior urethroplasty. Many men referred to referral centers for anterior urethral reconstruction often present soon after the endoscopic manipulation of severe strictures.

METHODS

We reviewed our database of all anterior urethroplasties performed by a single surgeon from 2007 to 2009. Urethral rest was accomplished by removal of the indwelling catheter, cessation of self-catheterization, and/or suprapubic urinary diversion before urethral reconstruction.

RESULTS

During the study period, 210 patients underwent urethral reconstruction at our center. Men who had undergone meatoplasty or posterior urethroplasty were excluded, leaving 128 anterior urethroplasty patients available for analysis. Of these men, 28 (21%) were preoperatively given an initial period of urethral rest (median duration 3 months) because of recent urologic manipulation occurring immediately before referral. Of the 28 patients, 15 (54%) received suprapubic catheters. Urethral rest promoted identification of severely fibrotic stricture segments, enabling focal or complete excision in 75% (excision and primary anastomosis in 12 [43%] and augmented anastomosis in 9 [32%]), a percentage similar to that for those undergoing reconstruction without preliminary manipulation mandating urethral rest (82%). Stricture recurrence developed in 4 (14%) of the 28 rest patients, a rate again similar to that for the remainder of the urethroplasty population (10%).

CONCLUSIONS

The results of our study have shown that recently manipulated anterior urethral strictures often declare themselves to be obliterative within several months of urethral rest, thus enabling successful urethroplasty by focal or complete excision.

A role for specific collagen motifs during wound healing and inflammatory response of fibroblasts in the teleost fish gilthead seabream

Specific sites and sequences in collagen to which cells can attach, either directly or through protein intermediaries, were identified using Toolkits of 63-amino acid triple-helical peptides and specific shorter GXX'GEX″ motifs, which have different intrinsic affinity for integrins that mediate cell adhesion and migration. We have previously reported that collagen type I (COL-I) was able to prime in vitro the respiratory burst and induce a specific set of immune- and extracellular matrix-related molecules in phagocytes of the teleost fish gilthead seabream (Sparus aurata L.). It was also suggested that COL-I would provide an intermediate signal during the early inflammatory response in gilthead seabream. Since fibroblasts are highly involved in the initiation of wound repair and regeneration processes, in the present study SAF-1 cells (gilthead seabream fibroblasts) were used to identify the binding motifs in collagen by end-point and real-time cell adhesion assays using the collagen peptides and Toolkits. We identified the collagen motifs involved in the early magnesium-dependent adhesion of these cells. Furthermore, we found that peptides containing the GFOGER and GLOGEN motifs (where O is hydroxyproline) present high affinity for SAF-1 adhesion, expressed as both cell number and surface covering, while in cell suspensions, these motifs were also able to induce the expression of the genes encoding the proinflammatory molecules interleukin-1β and cyclooxygenase-2. These data suggest that specific collagen motifs are involved in the regulation of the inflammatory and healing responses of teleost fish.

Pulmonary fibrosis: pathogenesis, etiology and regulation

Pulmonary fibrosis and architectural remodeling of tissues can severely disrupt lung function, often with fatal consequences. The etiology of pulmonary fibrotic diseases is varied, with an array of triggers including allergens, chemicals, radiation and environmental particles. However, the cause of one of the most common pulmonary fibrotic conditions, idiopathic pulmonary fibrosis (IPF), is still unclear. This review examines common mechanisms of pulmonary wound-healing responses following lung injury, and highlights the pathogenesis of some of the most widespread pulmonary fibrotic diseases. A three phase model of wound repair is reviewed that includes; (1) injury; (2) inflammation; and (3) repair. In most pulmonary fibrotic conditions dysregulation at one or more of these phases has been reported. Chronic inflammation can lead to an imbalance in the production of chemokines, cytokines, growth factors, and disrupt cellular recruitment. These changes coupled with excessive pro-fibrotic IL-13 and/or TGFbeta1 production can turn a well-controlled healing response into a pathogenic fibrotic response. Endogenous regulatory mechanisms are discussed including novel areas of therapeutic intervention. Restoring homeostasis to these dysregulated healing responses, or simply neutralizing the key pro-fibrotic mediators may prevent or slow the progression of pulmonary fibrosis.