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1.  Microbiology of diabetic foot infections: from Louis Pasteur to ‘crime scene investigation’ 
BMC Medicine  2015;13:2.
Were he alive today, would Louis Pasteur still champion culture methods he pioneered over 150 years ago for identifying bacterial pathogens? Or, might he suggest that new molecular techniques may prove a better way forward for quickly detecting the true microbial diversity of wounds? As modern clinicians faced with treating complex patients with diabetic foot infections (DFI), should we still request venerated and familiar culture and sensitivity methods, or is it time to ask for newer molecular tests, such as 16S rRNA gene sequencing? Or, are molecular techniques as yet too experimental, non-specific and expensive for current clinical use? While molecular techniques help us to identify more microorganisms from a DFI, can they tell us ‘who done it?’, that is, which are the causative pathogens and which are merely colonizers? Furthermore, can molecular techniques provide clinically relevant, rapid information on the virulence of wound isolates and their antibiotic sensitivities? We herein review current knowledge on the microbiology of DFI, from standard culture methods to the current era of rapid and comprehensive ‘crime scene investigation’ (CSI) techniques.
doi:10.1186/s12916-014-0232-0
PMCID: PMC4286146  PMID: 25564342
Molecular diagnostics; Diabetic foot infection; Microbiology; Metagenomics; High-throughput sequencing
2.  Intraoperative Fluorescence Vascular Angiography: During Tibial Bypass 
Preventing amputations in persons with lower extremity complications of diabetes is a complex endeavor, particularly in those with concomitant ischemia and tissue loss. Fluorescence angiography (Novadaq SPY system) may provide a tool for objective evaluations of tissue viability in the diabetic foot, which is an important indicator of the ability of the diabetic ulcer to heal adequately. The SPY system uses a low-power laser coupled with a charge-coupled device camera and indocyanine green (ICG) to sequence perfusion at the surface of the skin. We present an illustrated example of the potential utility of ICG fluorescence angiography (ICGFA) before and after vascular intervention in a high-risk limb. ICGFA appeared to reveal demarcation between viable and nonviable tissue and real-time perfusion, specifically capillary fill. ICGFA clarified the extent of necessary debridement and provided an immediate indication of improvement in regional perfusion status following revascularization. Future studies involving ICGFA may include pre- and postdebridement and closure perfusion, comparison of tissue perfusion pre- and post-endovascular therapy, and lower extremity flap viability. Future works will also address the consistency of results with ICGFA by analyzing a larger cohort of patients being treated by our unit.
PMCID: PMC3320839  PMID: 22401340
diabetic foot ulcers; noninvasive imaging; peripheral vascular disease; tissue health; wound healing
3.  Methodology for Use of a Neuroprosthetic to Reduce Plantar Pressure: Applications in Patients with Diabetic Foot Disease 
PMCID: PMC3320844  PMID: 22401344
diabetic foot ulcers; functional electrical stimulation; neuroprosthetics; plantar pressure; wound healing
4.  Diabetic Foot Ulcers and Vascular Insufficiency: Our Population Has Changed, but Our Methods Have Not 
Diabetic foot complications are increasing in prevalence worldwide. Care and attention to these complications have improved greatly. Many advanced therapies are now being investigated or taken through final stages of clinical studies worldwide. However, the data upon which assumptions regarding morbidity, healing, and mortality have been based are grossly outdated. The purpose of this brief article is to report on current data regarding neuropathic and neuroischemic wounds and to propose that the latter category of advanced-stage diabetic foot wound may now be emerging as the most commonly encountered lesion in the developed world. Unfortunately, it is still systematically excluded from most clinical study criteria. Additionally, just as in the care of cancer, we call for therapy of these advanced-stage diabetic foot ulcers to be managed in similarly interdisciplinary centers where patients may have access to potentially beneficial clinical trials.
PMCID: PMC3262731  PMID: 22226282
amputation; diabetic foot ulcers; infection; ischemia; wound healing
5.  Novel Use of Platelet-Rich Plasma to Augment Curative Diabetic Foot Surgery 
Autologous platelet-rich plasma (PRP) may enhance wound healing through the formation of a platelet plug that provides both hemostasis and the secretion of biologically active proteins, including growth factors such as platelet-derived growth factor, transforming growth factor (TGF)-β, TGF-β2, and epidermal growth factor. The release of these growth factors into the wound may create an environment more conducive to tissue repair and could accelerate postoperative wound healing. To our knowledge, there are no reports of combining the use of PRP with curative diabetic foot surgery. This article provides a summary of the literature regarding PRP and wound healing and presents a case of a 49-year-old man with diabetes and a three-month history of a deep, nonhealing plantar hallux wound in which PRP was combined with a first metatarsophalangeal joint arthroplasty. Through the use of the PRP and bioengineered tissue to supplement curative diabetic foot surgery, the patient healed uneventfully at seven weeks.
PMCID: PMC2956802  PMID: 20920431
diabetic; foot surgery; platelet rich plasma; wound
6.  Hydrodebridement of wounds: effectiveness in reducing wound bacterial contamination and potential for air bacterial contamination 
Background
The purpose of this study was to assess the level of air contamination with bacteria after surgical hydrodebridement and to determine the effectiveness of hydro surgery on bacterial reduction of a simulated infected wound.
Methods
Four porcine samples were scored then infected with a broth culture containing a variety of organisms and incubated at 37°C for 24 hours. The infected samples were then debrided with the hydro surgery tool (Versajet, Smith and Nephew, Largo, Florida, USA). Samples were taken for microbiology, histology and scanning electron microscopy pre-infection, post infection and post debridement. Air bacterial contamination was evaluated before, during and after debridement by using active and passive methods; for active sampling the SAS-Super 90 air sampler was used, for passive sampling settle plates were located at set distances around the clinic room.
Results
There was no statistically significant reduction in bacterial contamination of the porcine samples post hydrodebridement. Analysis of the passive sampling showed a significant (p < 0.001) increase in microbial counts post hydrodebridement. Levels ranging from 950 colony forming units per meter cubed (CFUs/m3) to 16780 CFUs/m3 were observed with active sampling of the air whilst using hydro surgery equipment compared with a basal count of 582 CFUs/m3. During removal of the wound dressing, a significant increase was observed relative to basal counts (p < 0.05). Microbial load of the air samples was still significantly raised 1 hour post-therapy.
Conclusion
The results suggest a significant increase in bacterial air contamination both by active sampling and passive sampling. We believe that action might be taken to mitigate fallout in the settings in which this technique is used.
doi:10.1186/1757-1146-2-13
PMCID: PMC2694772  PMID: 19426486
7.  Nonlinear modeling of venous leg ulcer healing rates 
BMC Dermatology  2009;9:2.
Background
The purpose of this manuscript was to determine whether the change in wound surface area over time could be described through nonlinear mathematics.
Methods
We studied 3,588 serial wound tracings of 338 venous leg ulcers (VLUs) that had been followed during a controlled, prospective, randomized trial of two topical wound treatments.
Results
A majority (72%) of VLUs exhibited surface area reduction via an exponential decay model, particularly during the early stages of healing. These results were consistent with the mechanics of wound contraction and epithelial cell proliferation, supported by the higher frequency at which exponential surface area reduction associated with full wound closure (35% of wounds that fit the exponential model healed vs. 21% of wounds that did not fit the exponential model completely healed during the study period, p = 0.018). Goodness-of-fit statistics suggested that much of the individual variation in healing could be described as nonlinear variation from the exponential model.
Conclusion
We believe that parameter estimates from a mathematical model may provide a more accurate quantification of wound healing rates, and that similar models may someday reach routine use in comparing the efficacy of various treatments in routine practice and in product registration trials.
doi:10.1186/1471-5945-9-2
PMCID: PMC2672927  PMID: 19335882
8.  Foot ulcers in the diabetic patient, prevention and treatment 
Lower extremity complications in persons with diabetes have become an increasingly significant public health concern in both the developed and developing world. These complications, beginning with neuropathy and subsequent diabetic foot wounds frequently lead to infection and lower extremity amputation even in the absence of critical limb ischemia. In order to diminish the detrimental consequences associated with diabetic foot ulcers, a com-mon-sense-based treatment approach must be implemented. Many of the etiological factors contributing to the formation of diabetic foot ulceration may be identified using simple, inexpensive equipment in a clinical setting. Prevention of diabetic foot ulcers can be accomplished in a primary care setting with a brief history and screening for loss of protective sensation via the Semmes-Weinstein monofilament. Specialist clinics may quantify neuropathy, plantar foot pressure, and assess vascular status with Doppler ultrasound and ankle-brachial blood pressure indices. These measurements, in conjunction with other findings from the history and physical examination, may enable clinicians to stratify patients based on risk and help determine the type of intervention. Other effective clinical interventions may include patient education, optimizing glycemic control, smoking cessation, and diligent foot care. Recent technological advanced combined with better understanding of the wound healing process have resulted in a myriad of advanced wound healing modalities in the treatment of diabetic foot ulcers. However, it is imperative to remember the fundamental basics in the healing of diabetic foot ulcers: adequate perfusion, debridement, infection control, and pressure mitigation. Early recognition of the etiological factors along with prompt management of diabetic foot ulcers is essential for successful outcome.
PMCID: PMC1994045  PMID: 17583176
diabetes; ulcer; prevention; infection; amputation
9.  Activin promotes oocyte development in ovine preantral follicles in vitro 
Activins have been implicated as important regulating factors for many reproductive processes. The aim of this study was to determine the effect of activin A on the development of ovine preantral follicles in vitro. Mechanically isolated preantral follicles (161 ± 2 microm) were cultured for 6 days in the presence of human recombinant activin A (0, 10 and 100 ng/ml). Half of the medium was replaced every second day and follicle diameters were measured. Conditioned medium was subsequently analysed for oestradiol content using a delayed enhancement lanthanide fluorometric immunoassay (DELFIA). At the end of the culture period, follicles were fixed and processed for histology, after which oocyte diameter and granulosa cell death were measured. There was significant follicle growth over 6 days in all groups (p < 0.001). Activin, at both concentrations, increased follicle growth over control levels by Day 6 (p < 0.05). Oocyte diameters were also significantly increased by Day 6 of culture in all groups (p < 0.05), with 100 ng/ml activin increasing oocyte diameter over control levels (p < 0.05). Activin, at both concentrations, increased oestradiol production on Day 2 of culture, but this increase was not sustained during the culture period. Moreover, activin did not have any effect on antrum formation or follicle survival. In conclusion, activin promoted ovine preantral follicle and oocyte growth in vitro, but did not accelerate follicle differentiation over a six-day culture period. These results support a paracrine role for activin A during early oocyte and follicular development.
doi:10.1186/1477-7827-1-76
PMCID: PMC280721  PMID: 14613548
10.  The Effect of a Connexin43-Based Peptide on the Healing of Chronic Venous Leg Ulcers: A Multicenter, Randomized Trial 
The gap junction protein, connexin43 (Cx43), has critical roles in the inflammatory, edematous, and fibrotic processes following dermal injury and during wound healing, and is abnormally upregulated at the epidermal wound margins of venous leg ulcers (VLUs). Targeting Cx43 with ACT1, a peptide mimetic of the carboxyl-terminus of Cx43, accelerates fibroblast migration and proliferation, and wound reepithelialization. In a prospective, multicenter clinical trial conducted in India, adults with chronic VLUs were randomized to treatment with an ACT1 gel formulation plus conventional standard-of-care (SOC) protocols, involving maintaining wound moisture and four-layer compression bandage therapy, or SOC protocols alone. The primary end point was mean percent ulcer reepithelialization from baseline to 12 weeks. A significantly greater reduction in mean percent ulcer area from baseline to 12 weeks was associated with the incorporation of ACT1 therapy (79% (SD 50.4)) as compared with compression bandage therapy alone (36% (SD 179.8); P=0.02). Evaluation of secondary efficacy end points indicated a reduced median time to 50 and 100% ulcer reepithelialization for ACT1-treated ulcers. Incorporation of ACT1 in SOC protocols may represent a well-tolerated, highly effective therapeutic strategy that expedites chronic venous ulcer healing by treating the underlying ulcer pathophysiology through Cx43-mediated pathways.
doi:10.1038/jid.2014.318
PMCID: PMC4269806  PMID: 25072595

Results 1-10 (10)