Adjunct methods of the standard diabetic foot ulceration therapy

Hyperbaric oxygen enhances collagen III formation in wound of ZDF rat

Diabetic foot ulcer (DFU) is a serious complication of diabetes and hyperbaric oxygen therapy (HBOT) is also considered in comprehensive treatment. The evidence supporting the use of HBOT in DFU treatment is controversial. The aim of this work was to introduce a DFU model in ZDF rat by creating a wound on the back of an animal and to investigate the effect of HBOT on the defect by macroscopic evaluation, quantitative histological evaluation of collagen (types I and III), evaluation of angiogenesis and determination of interleukin 6 (IL6) levels in the plasma. The study included 10 rats in the control group (CONT) and 10 in the HBOT group, who underwent HBOT in standard clinical regimen. Histological evaluation was performed on the 18th day after induction of defect. The results show that HBOT did not affect the macroscopic size of the defect nor IL6 plasma levels. A volume fraction of type I collagen was slightly increased by HBOT without reaching statistical significance (1.35+/-0.49 and 1.94+/-0.67 %, CONT and HBOT, respectively). In contrast, the collagen type III volume fraction was ~120 % higher in HBOT wounds (1.41+/-0.81 %) than in CONT ones (0.63+/-0.37 %; p=0.046). In addition, the ratio of the volume fraction of both collagens in the wound ((I+III)w) to the volume fraction of both collagens in the adjacent healthy skin ((I+III)h) was ~65 % higher in rats subjected to HBOT (8.9+/-3.07 vs. 5.38+/-1.86 %, HBOT and CONT, respectively; p=0.028). Vessels density (number per 1 mm2) was found to be higher in CONT vs. HBOT (206.5+/-41.8 and 124+/-28.2, respectively, p<0.001). Our study suggests that HBOT promotes collagen III formation and decreases the number of newly formed vessels at the early phases of healing.

A molecular approach to maggot debridement therapy with Lucilia sericata and its excretions/secretions in wound healing

Chronic wounds caused by underlying physiological causes such as diabetic wounds, pressure ulcers, venous leg ulcers and infected wounds affect a significant portion of the population. In order to treat chronic wounds, a strong debridement, removal of necrotic tissue, elimination of infection and stimulation of granulation tissue are required. Maggot debridement therapy (MDT), which is an alternative treatment method based on history, has been used quite widely. MDT is an efficient, simple, cost-effective and reliable biosurgery method using mostly larvae of Lucilia sericata fly species. Larvae can both physically remove necrotic tissue from the wound site and stimulate wound healing by activating molecular processes in the wound area through the enzymes they secrete. The larvae can stimulate wound healing by activating molecular processes in the wound area through enzymes in their excretions/secretions (ES). Studies have shown that ES has antibacterial, antifungal, anti-inflammatory, angiogenic, proliferative, hemostatic and tissue-regenerating effects both in vivo and in vitro. It is suggested that these effects stimulate wound healing and accelerate wound healing by initiating a direct signal cascade with cells in the wound area. However, the enzymes and peptides in ES are mostly still undefined. Examining the molecular content of ES and the biological effects of these ingredients is quite important to illuminate the molecular mechanism underlying MDT. More importantly, ES has the potential to have positive effects on wound healing and to be used more as a therapeutic agent in the future, so it can be applied as an alternative to MDT in wound healing.

Immune-Based Anti-Staphylococcal Therapeutic Approaches

Widespread methicillin-resistant Staphylococcus aureus (S. aureus) infections within community and healthcare settings are responsible for accelerated development of antibiotic resistance. As the antibiotic pipeline began drying up, alternative strategies were sought for future treatment of S. aureus infections. Here, we review immune-based anti-staphylococcal strategies that, unlike conventional antibiotics, target non-essential gene products elaborated by the pathogen. These strategies stimulate narrow or broad host immune mechanisms that are critical for anti-staphylococcal defenses. Alternative approaches aim to disrupt bacterial virulence mechanisms that enhance pathogen survival or induce immunopathology. Although immune-based therapeutics are unlikely to replace antibiotics in patient treatment in the near term, they have the potential to significantly improve upon the performance of antibiotics for treatment of invasive staphylococcal diseases.

The Clinical Value of the RA-Adjusted Fracture Risk Assessment Tool in the Fracture Risk Prediction of Patients with Type 2 Diabetes Mellitus in China

Objective

This study aimed to explore the clinical value of the fracture risk assessment tool (FRAX) in the fracture risk prediction of Chinese patients after replacing rheumatoid arthritis (RA) with type 2 diabetes mellitus (T2DM) in the FRAX algorithm.

Methods

A total of 1,047 patients with T2DM from the Endocrinology Department of the Third Affiliated Hospital of Nanchang University were enrolled in this study. Dual-energy X-ray absorptiometry (DXA) was then used to detect their bone density. RA in the FRAX algorithm was replaced with T2DM, and the new RA-adjusted FRAX was used to assess the fracture risk of the patients.

Results

The sensitivity, specificity, and Youden’s index of the RA-adjusted FRAX to the treatment opinions on T2DM-associated hip fractures were 0.4761, 0.9642, and 0.4403, respectively, while the sensitivity, specificity, and Youden’s index of RA-adjusted FRAX to the treatment opinions on T2DM-associated major bone osteoporotic fractures were 0.0080, 1.0000, 0.0080, respectively. The DXA and RA-adjusted FRAX both showed acceptable consistency in the treatment recommendations for hip fractures in patients with T2DM (κ = 0.49) but had poor consistency in treatment recommendations for major bone osteoporotic fractures (κ = 0.010). The body mass index (BMI) scores, femoral neck-bone mineral densities, and number of males in the same treatment opinion group were significantly higher than in the different treatment opinions group (P < 0.001).

Conclusion

RA-adjusted FRAX is a useful clinical tool for evaluation of hip fracture risk for Chinese patients with T2DM, and the accuracy of fracture risk prediction for male patients with T2DM and patients with T2DM with high BMI scores or high femoral neck-bone mineral density is higher.

Biofabrication of thick vascularized neo-pedicle flaps for reconstructive surgery

Wound chronicity due to intrinsic and extrinsic factors perturbs adequate lesion closure and reestablishment of the protective skin barrier. Immediate and proper care of chronic wounds is necessary for a swift recovery and a reduction of patient vulnerability to infection. Advanced therapies supplemented with standard wound care procedures have been clinically implemented to restore aberrant tissue; however, these treatments are ineffective if local vasculature is too compromised to support minimally-invasive strategies. Autologous "flaps", which are tissues equipped with their own hierarchical vascular supply, can be harvested from one region of the patient and transplanted to the wound where it is reperfused upon microsurgical anastomosis to appropriate recipient vessels. Despite the success of autologous flap transfer, these procedures are extremely invasive, incur obligatory donor-site morbidity, and require sufficient donor-tissue availability, microsurgical expertise, and specialized equipment. 3D-bioprinting modalities, such as extrusion-based bioprinting, can be used to address the clinical constraints of autologous flap transfer, primarily addressing donor-site morbidity and tissue availability. This advancement in regenerative medicine allows the biofabrication of heterogeneous tissue structures with high shape fidelity and spatial resolution to generate biomimetic constructs with the anatomically-precise geometries of native tissue to ensure tissue-specific function. Yet, meaningful progress toward this clinical application has been limited by the lack of vascularization required to meet the nutrient and oxygen demands of clinically relevant tissue volumes. Thus, various criteria for the fabrication of functional tissues with hierarchical, patent vasculature must be considered when implementing 3D-bioprinting technologies for deep, chronic wounds.

Platelet-Rich Plasma for the Treatment of Tissue Infection: Preparation and Clinical Evaluation

IMPACT STATEMENT

The clinical application of platelet-rich plasma (PRP) has been widely studied for its effects on trauma or injury repair/regeneration, however the antibacterial property of PRP has been overlooked. Increasing evidence suggests PRP as a good antibacterial agent and that it could help prevent/treat tissue infection. This review emphasizes the importance of PRP's antibacterial property and summarizes the preclinical and clinical findings regarding the application of PRP in the prevention and treatment of wound and bone infection. The use of biocompatible PRP may be advantageous for tissue infection treatment due to its inherent antibacterial and healing promoting properties.

A Pilot Study of Short-Duration Hyperbaric Oxygen Therapy to Improve HbA1c, Leukocyte, and Serum Creatinine in Patients with Diabetic Foot Ulcer Wagner 3-4

Objective

To evaluate the short-duration hyperbaric oxygen therapy (HBOT) can improve HbA1c levels, leukocyte count, and serum creatinine levels in patients with diabetic foot ulcer (DFU) Wagner 3-4.

Methods

Blood samples from all DFU patients at Sanglah General Hospital, Denpasar, were taken for HbA1c, leukocyte, and serum creatinine test before debridement procedure, and the patients were then grouped into either standard therapy or standard therapy with HBOT for 10 sessions (combination therapy). At the end of therapy, all blood tests were resumed.

Results

Each group consisted of 15 patients. Results of laboratory analysis before and after treatment were significant regarding decrease of HbA1c levels in standard therapy (10.98 ± 2.37 % to 9.70 ± 2.46 %; p = 0.006), HbA1c levels in combination therapy (9.42 ± 1.96 % to 7.07 ± 1.16 %; p < 0.001), and leukocyte count in combination therapy (13.97 ± 6.24 x 10³ cells/μL to 8.84 ± 2.88 x 10³ cells/μL; p = 0.009). The HbA1c levels at the end of therapy were significantly different between groups (p = 0.001). Serum creatinine level was decreased only in combination therapy but it was not significant. The effect size of all variables was larger in the combination therapy, but it was not significant (p > 0.05).

Conclusion

The use of short-duration HBOT on DFU reduces HbA1c levels, leukocyte count, and serum creatinine levels better than standard therapy alone. This protocol would save time and effort in future HBOT implementation. This trial is registered with ClinicalTrials.gov Identifier: NCT03615755.

Quality control of a medicinal larval (Lucilia sericata) debridement device based on released gelatinase activity

Lucilia sericata Meigen (Diptera: Calliphoridae) larvae are manufactured worldwide for the treatment of chronic wounds. Published research has confirmed that the primary clinical effect of the product, debridement (the degradation of non-viable wound tissue), is accomplished by a range of enzymes released by larvae during feeding. The quality assessment of larval activity is currently achieved during production using meat-based assays, which monitor insect growth and/or the reduction in substrate mass. To support this, the present authors developed a complementary radial diffusion enzymatic assay to produce a visual and measureable indication of the activity of larval alimentary products (LAP) collected under standardized conditions, against a gelatin substrate. Using basic laboratory equipment and reagents, the assay is rapid and suited to high throughput. Assay reproducibility is high (standard deviation: 0.06-0.27; coefficient of variation: 0.75-4.31%) and the LAP collection procedure does not adversely affect larval survival (mortality: < 2%). Because it is both cost- and time-effective, this method is suited to both academic and industrial use and supports good manufacturing and laboratory practice as a quality control assay.

Dying blood mononuclear cell secretome exerts antimicrobial activity

BACKGROUND

Several activities are attributed to antimicrobial peptides (AMPs), including bacterial killing, leucocyte recruitment and angiogenesis. Despite promises of advanced cellular therapies for treatment of diabetic foot ulcer, it is currently accepted that paracrine factors rather than cellular components are causative for the observed effects. Whether AMPs are present in the mononuclear cell (MNC) secretome (MNC-sec) of white blood cells that are beneficial in experimental wound healing is not known.

MATERIALS AND METHODS

Antimicrobial activity of the secretomes of nonirradiated (MNC-sec) and γ-irradiated MNCs (MNC-sec rad) was analysed by microdilution assay. AMPs were determined by quantitative real-time PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Whether human MNC-sec rad causes AMP secretion in vivo was examined in an experimental rat model. Image flow cytometry was used to determine the type of cell death induced in MNCs after exposure to γ-radiation.

RESULTS

The antimicrobial activity assay revealed a bactericidal activity of MNC-sec rad and to a lesser degree also of MNC-sec. Image flow cytometry showed that γ-irradiation of MNCs induced early apoptosis followed mainly by necroptosis. RT-PCR and ELISA revealed a high abundance of different AMPs in the secretome of MNCs. In addition, human MNC-sec elicited an increase in de novo endogenous AMP production in rats in vivo.

CONCLUSION

We provide evidence that the secretome of MNCs has direct and indirect positive effects on the immune defence system, including augmentation of antibacterial properties. Our data further suggest that necroptosis could play a key role for the release of paracrine factors and the therapeutic action of MNC-sec rad.

Platelet-rich plasma, bilayered acellular matrix grafting and negative pressure wound therapy in diabetic foot infection

Management and treatment of acute severe diabetic foot disease in patients with suboptimal glycaemic control is a critical issue in wound repair. This paper discusses the clinical efficacy of an aggressive surgical intervention combined with targeted use of regenerative medical therapies in limb preservation. Negative pressure wound therapy (NPWT), platelet-rich plasma (PRP), bilayered acellular matrix grafting and split-thickness skin grafting were combined to treat a patient with diabetes, foot necrotising fasciitis and gaseous gangrene. The wound was completely healed. The clinical outcome revealed that a multi-intervention strategy could be effective for large necrotising fasciitis wounds. Early clinical observation, suggests aggresive surgical intervention preserving intact tissue and targeted use of new regenerative technologies can lead to preservation of a limb.

DECLARATION OF INTEREST

The authors have received no financial support for the material presented in this study outside of the scope of standard patient care reimbursement. This work was supported by the National Natural Science Foundation of China (NO. 81500596) awarded to Dr Wuquan Deng.

Maggot debridement therapy as primary tool to treat chronic wound of animals

Maggot debridement therapy (MDT) is a safe, effective, and controlled method ofhealing of chronic wounds by debridement and disinfection. In this therapy live, sterile maggots of green bottle fly, Lucilia (Phaenicia) sericata are used, as they prefernecrotic tissues over healthy for feeding. Since centuries, MDT is used in humanbeings to treat chronic wounds. Lately, MDT came out as a potent medical aid in animals. In animals, although, this therapy is still limited and clinical studies are few. However, with the increasing antibiotic resistance and chronic wound infections in veterinary medicine, maggot therapy may even become the first line of treatment for some infections. This paper will present a brief discussion of MDT and its role in veterinary medicine that may add one more treatment method to utilize in non-healing wounds of animals and overcome the use of amputation and euthanasia. The objective of this review paper is to assemble relevant literature on maggot therapy to form a theoretical foundation from which further steps toward clinical use of maggot therapy in animals for chronic wounds can be taken.

Maggot debridement therapy promotes diabetic foot wound healing by up-regulating endothelial cell activity

To determine the role of maggot debridement therapy (MDT) on diabetic foot wound healing, we compared growth related factors in wounds before and after treatment. Furthermore, we utilized human umbilical vein endothelial cells (HUVECs) to explore responses to maggot excretions/secretions on markers of angiogenesis and proliferation. The results showed that there was neo-granulation and angiogenesis in diabetic foot wounds after MDT. Moreover, significant elevation in CD34 and CD68 levels was also observed in treated wounds. In vitro, ES increased HUVEC proliferation, improved tube formation, and increased expression of vascular endothelial growth factor receptor 2 in a dose dependent manner. These results demonstrate that MDT and maggot ES can promote diabetic foot wound healing by up-regulating endothelial cell activity.

Circulating endothelial progenitor cells and angiogenic factors in diabetes complicated diabetic foot and without foot complications

INTRODUCTION

Data about angiogenic factors in diabetic foot syndrome (DFS) are insufficient. Therefore, in the present study we focus on circulating endothelial progenitor cells (EPCs) and two major angiogenic factors: vascular endothelial growth factor (VEGF-A) and fibroblast growth factor (FGF-2) in patients with DFS.

MATERIALS AND METHODS

We included 75 subjects: 45 patients with type 2 diabetes and 30 controls. The study group was divided into 2 subgroups: 23 patients with diabetic foot and 22 patients without diabetic complications. The concentration of VEGF-A, soluble VEGF receptor 2 (sVEGF-R2) and FGF-2 were measured in plasma samples. The number of circulating EPCs was determined in peripheral venous blood. The number of endothelial progenitor cells was measured with FACSCalibur flow cytometer using monoclonal antibodies directed against antigens specific for EPCs.

RESULTS

In our study we observed significant higher levels of VEGF-A and FGF-2 and lower sVEGF-R2 concentration in patients with T2DM compared to healthy subjects. The conducted analysis showed decreased levels of VEGF-A and elevated levels of FGF-2 in patients with DM complicated DFS compared to diabetic patients without DFS. Increased circulating EPCs number was reported in patients with DFS, and the difference was almost statistically significant.

CONCLUSIONS

The high concentration of VEGF-A and FGF-2, and a positive correlation between them indicate their participation in the process of angiogenesis in T2DM. Decreased sVEGF-R2 may result from inactivation of VEGF-A during complexes formation.

Platelet-Rich Plasma Promotes Axon Regeneration, Wound Healing, and Pain Reduction: Fact or Fiction

Platelet-rich plasma (PRP) has been tested in vitro, in animal models, and clinically for its efficacy in enhancing the rate of wound healing, reducing pain associated with injuries, and promoting axon regeneration. Although extensive data indicate that PRP-released factors induce these effects, the claims are often weakened because many studies were not rigorous or controlled, the data were limited, and other studies yielded contrary results. Critical to assessing whether PRP is effective are the large number of variables in these studies, including the method of PRP preparation, which influences the composition of PRP; type of application; type of wounds; target tissues; and diverse animal models and clinical studies. All these variables raise the question of whether one can anticipate consistent influences and raise the possibility that most of the results are correct under the circumstances where PRP was tested. This review examines evidence on the potential influences of PRP and whether PRP-released factors could induce the reported influences and concludes that the preponderance of evidence suggests that PRP has the capacity to induce all the claimed influences, although this position cannot be definitively argued. Well-defined and rigorously controlled studies of the potential influences of PRP are required in which PRP is isolated and applied using consistent techniques, protocols, and models. Finally, it is concluded that, because of the purported benefits of PRP administration and the lack of adverse events, further animal and clinical studies should be performed to explore the potential influences of PRP.

Maggot debridement therapy: a systematic review

Maggot debridement therapy is used extensively in the UK in both community and hospital situations, but remains a potentially under-used modality in many wound care markets. It promotes wound healing by performing three key processes: debridement, disinfection and growth-promoting activity. It can be used for the debridement of non-healing necrotic skin and soft tissue wounds, including pressure ulcers, venous stasis ulcers, neuropathic foot ulcers and non-healing traumatic of post-surgical wounds. With the increase in chronic diabetic foot wounds, maggot debridement therapy is a promising tool for health professionals dealing with difficult wounds. This article presents an overview of the research evidence surrounding maggot debridement therapy that serves as a guide to health professionals who may be users of this form of treatment now and in the future.

A comparative clinical study on five types of compression therapy in patients with venous leg ulcers

The aim of this study was to compare five types of compression therapy in venous leg ulcers (intermittent pneumatic vs. stockings vs. multi layer vs. two layer short stretch bandages vs. Unna boots). Primary study endpoints were analysis of changes of the total ulcer surface area, volume and linear dimensions inside observed groups. The secondary end points were comparisons between all groups the number of completely healed wounds (ulcer healing rates), Gilman index and percentage change of ulcer surface area. In total, 147 patients with unilateral venous leg ulcers were included to this study. Participants were randomly allocated to the groups: A, B, C, D and E. After two months the healing rate was the highest in group A (intermittent pneumatic compression) - 57.14%, 16/28 patients, B (ulcer stocking system) - 56.66%, 17/30 patients and C (multi layer short stretch bandage) - 58.62%, 17/29 patients. Significantly much worse rate found in group D (two layer short stretch bandages) - only 16.66%, 5/30 patients and E (Unna boots) - 20%, 6/30 patients. The analysis of changes of the percentage of Gilman index and wound total surface area confirmed that intermittent pneumatic compression, stockings and multi layer bandages are the most efficient. The two layer short - stretch bandages and Unna boots appeared again much less effective.