Vagus nerve stimulation: Potential for treating chronic wounds

Vagus nerve stimulation (VNS) has been approved as a treatment for various conditions, including drug-resistant epilepsy, migraines, chronic cluster headaches and treatment-resistant depression. It is known to have anti-inflammatory, anti-nociceptive and anti-adrenergic effects, and its therapeutic potential for diverse pathologies is being investigated. VNS can be achieved through invasive (iVNS) or non-invasive (niVNS) means, targeting different branches of the vagus nerve. iVNS devices require surgical implantation and have associated risks, while niVNS devices are generally better tolerated and have a better safety profile. Studies have shown that both iVNS and niVNS can reduce inflammation and pain perception in patients with acute and chronic conditions. VNS devices, such as the VNS Therapy System and MicroTransponder Vivistim, have received Food and Drug Administration approval for specific indications. Other niVNS devices, like NEMOS and gammaCore, have shown effectiveness in managing epilepsy, pain and migraines. VNS has also demonstrated potential in autoimmune disorders, such as rheumatoid arthritis and Crohn's disease, as well as neurological disorders like epilepsy and migraines. In addition, VNS has been explored in cardiovascular disorders, including post-operative atrial fibrillation and myocardial ischemia-reperfusion injury, and has shown positive outcomes. The mechanisms behind VNS's effects include the cholinergic anti-inflammatory pathway, modulation of cytokines and activation of specialised pro-resolving mediators. The modulation of inflammation by VNS presents a promising avenue for investigating its potential to improve the healing of chronic wounds. However, more research is needed to understand the specific mechanisms and optimise the use of VNS in wound healing. Ongoing clinical trials may support the use of this modality as an adjunct to improve healing.

Patterns of use of advanced wound matrices in the Veterans Administration clinics

Chronic wounds are a common and costly health issue affecting millions of individuals in the United States, particularly those with underlying conditions such as diabetes, venous insufficiency, and peripheral artery disease. When standard treatments fail, advanced wound care therapies, such as skin substitutes, are often applied. However, the clinical effectiveness, indications, and comparative benefits of these therapies have not been well established. In this study, we report on the usage of both acellular and cellular, single and bilayer, natural and synthetic, dermal, and epidermal skin substitutes in a VA hospital system. We performed a retrospective chart review to understand the ordering and usage patterns of advanced wound therapies for patients with chronic wounds at the VA Northern California Health Care System. We examined types of products being recommended, categories of users recommending the products, indications for orders, and rate of repeated orders. Neuropathic, venous, or pressure ulcers were the main indications for using advanced wound matrices. Only 15.6% of patients for whom the matrices were ordered had supporting laboratory tests. Exactly 34.3% of the ordered matrices were not applied. And the use of wound matrices resulted in increased costs per patient visit of $1018-$3450. Our study sheds light on the usage patterns of these therapies in a VA healthcare facility and highlights the need for more robust evidence-based studies to determine the true benefits, efficacy, and cost-effectiveness of these innovative treatment options.

Cold atmospheric plasma for surface disinfection: a promising weapon against deleterious meticillin-resistant Staphylococcus aureus biofilms

BACKGROUND

Bacteria are becoming increasingly resistant to classical antimicrobial agents, so new approaches need to be explored.

AIM

To assess the potential of cold atmospheric plasma for the management of meticillin-resistant Staphylococcus aureus (MRSA).

METHODS

The 24, 48, and 72 h resistant and susceptible S. aureus biofilms were exposed to 60, 120, and 180 s treatment with plasma.

FINDINGS

Increasing the treatment time results in higher cell reduction for both susceptible and resistant strains of S. aureus (P < 0.05). Up to log10 reduction factor of 5.24 cfu/cm2 can be achieved in 180 s of plasma treatment. Furthermore, plasma can substantially alter the cell's metabolisms and impact cell membrane integrity. However, it has not been shown that plasma can reduce biofilm biomass in the case of 24 h and 48 h biofilms, although the 72 h biofilm was more susceptible, and its biomass was decreased (P < 0.05). The accumulation of intrabacterial reactive oxygen species was also observed, which confirms the plasma's induction of oxidative stress. Finally, it was shown that continuous plasma exposure of bacterial cells does not cause resistance to plasma, nor is resistance developed to cefoxitin.

CONCLUSION

Cold atmospheric plasma is a good candidate for S. aureus and MRSA biofilm treatment and may therefore be of value in the bacterial resistance crisis.

Potential Allergens in Wound Care Products

Background: Patients with chronic wounds have an increased risk of developing allergic contact dermatitis (ACD). Reports of ACD to wound care products are not uncommon. To minimize contact sensitization in patients with chronic wounds, allergenic ingredients should be avoided when possible. Objective: With more than 5000 wound care products available in the United States, it is essential to understand which products can be chosen to minimize allergen exposures. Methods: Ingredients in wound care products in 5 wound care clinics across 2 institutions were cross-referenced with the American Contact Dermatitis Society core allergen series 2020. Results: Of the 267 wound care products included, 97 (36.3%) contained at least one allergen, including 31 dressings/wraps (22.3%), 25 medications (69.4%), 12 cleaning supplies (36.3%), 16 tapes/glues (80%), 2 instruments (14.3%), 8 emollients and vehicles (61.5%), 1 ostomy product (11.1%), and 2 odor-eliminating products (66.7%). Thirty-four different allergens were identified across all products. The most common allergens present in the included items were acrylates and propylene glycol, followed by parabens, cetyl stearyl alcohol, tocopherol, fragrance, and phenoxyethanol. Conclusions: Many wound care products contain at least one contact allergen, highlighting the importance of clinician education on ACD in the context of wound care product selection.

Potential Allergens in Wound Care Products

BACKGROUND

Patients with chronic wounds have an increased risk of developing allergic contact dermatitis (ACD). Reports of ACD to wound care products are not uncommon. To minimize contact sensitization in patients with chronic wounds, allergenic ingredients should be avoided when possible.

OBJECTIVE

With more than 5000 wound care products available in the United States, it is essential to understand which products can be chosen to minimize allergen exposures.

METHODS

Ingredients in wound care products in 5 wound care clinics across 2 institutions were cross-referenced with the American Contact Dermatitis Society core allergen series 2020.

RESULTS

Of the 267 wound care products included, 97 (36.3%) contained at least one allergen, including 31 dressings/wraps (22.3%), 25 medications (69.4%), 12 cleaning supplies (36.3%), 16 tapes/glues (80%), 2 instruments (14.3%), 8 emollients and vehicles (61.5%), 1 ostomy product (11.1%), and 2 odor-eliminating products (66.7%). Thirty-four different allergens were identified across all products. The most common allergens present in the included items were acrylates and propylene glycol, followed by parabens, cetyl stearyl alcohol, tocopherol, fragrance, and phenoxyethanol.

CONCLUSIONS

Many wound care products contain at least one contact allergen, highlighting the importance of clinician education on ACD in the context of wound care product selection.

Acral Amelanotic Melanoma Mimicking a Foot Ulcer

Acral amelanotic melanoma can be difficult to diagnose and is often clinically aggressive. The present report describes a case of an acral amelanotic melanoma presenting as a non-healing wound after mimicking a plantar wart for two years. The decision to biopsy a borderline-suspicious lesion on the lower extremity in an elderly individual must be weighed carefully, as lower extremity biopsy carries a risk of poor wound healing and other complications. We discuss clinical and epidemiologic features that can assist in deciding when to perform a biopsy in this setting and can improve the early detection of acral amelanotic melanoma.

Application of Intralesion Ultrasound-Guided Laser Ablation for Plantar Foot Mass Involving Arteriovenous Fistula: A Case Report

Penetrating and blunt trauma to the plantar aspect of the foot are common. Both penetrating and blunt trauma may be associated with an injury to the blood vessels, which may go undetected clinically. A minor puncture, blunt trauma and repeated blunt trauma can injure small arteries leading to an arteriovenous fistula (AVF). The arterial rupture leads to a system of veins creating a small AVF and appearing clinically as a blue colored, painful lesion. A case of such an injury is presented where the clinical examination, magnetic resonance arteriogram and point of service ultrasound with duplex imaging was used to diagnose the AVF. The AVF was treated in the clinic with a percutaneous ultrasound-guided laser procedure. The laser procedure was effective and there was minimal post procedural morbidity.

Plasma chemical and chemical functionalization of polystyrene colloidal crystals

A method to stabilize templates of colloidal crystals for subsequent electrochemical deposition from ionic liquids is presented.

Cellular versus acellular matrix devices in treatment of diabetic foot ulcers: study protocol for a comparative efficacy randomized controlled trial

Background

Diabetic foot ulcers (DFUs) represent a significant source of morbidity and an enormous financial burden. Standard care for DFUs involves systemic glucose control, ensuring adequate perfusion, debridement of nonviable tissue, off-loading, control of infection, local wound care and patient education, all administered by a multidisciplinary team. Unfortunately, even with the best standard of care (SOC) available, only 24% or 30% of DFUs will heal at weeks 12 or 20, respectively.

The extracellular matrix (ECM) in DFUs is abnormal and its impairment has been proposed as a key target for new therapeutic devices. These devices intend to replace the aberrant ECM by implanting a matrix, either devoid of cells or enhanced with fibroblasts, keratinocytes or both as well as various growth factors. These new bioengineered skin substitutes are proposed to encourage angiogenesis and in-growth of new tissue, and to utilize living cells to generate cytokines needed for wound repair.

To date, the efficacy of bioengineered ECM containing live cellular elements for improving healing above that of a SOC control group has not been compared with the efficacy of an ECM devoid of cells relative to the same SOC. Our hypothesis is that there is no difference in the improved healing effected by either of these two product types relative to SOC.

Methods/Design

To test this hypothesis we propose a randomized, single-blind, clinical trial with three arms: SOC, SOC plus Dermagraft® (bioengineered ECM containing living fibroblasts) and SOC plus Oasis® (ECM devoid of living cells) in patients with nonhealing DFUs. The primary outcome is the percentage of subjects that achieved complete wound closure by week 12.

Discussion

If our hypothesis is correct, then immense cost savings could be realized by using the orders-of-magnitude less expensive acellular ECM device without compromising patient health outcomes. The article describes the protocol proposed to test our hypothesis.

Trial registration

ClinicalTrials.gov: NCT01450943. Registered: 7 October 2011

Effects of an external nasal dilator strip (ENDS) compared to xylometazolin nasal spray

Nasal blockage is a common complaint in Family Practice. Decongestive nosedrops are frequently employed therapeutic measures. Due to a considerable risk of abuse and side effects, alternatives are wanted. The purpose of this study was to elucidate to what extent ENDS might represent an alternative to decongestive nose sprays (DNS). The effects of DNS (xylometazolin) and ENDS (BreatheRight) on subjective and objective nasal blockage were compared in 89 patients. Main outcome measures were recordings of nasal symptom scores on visual analogue scales (VAS), minimal cross-sectional areas (MCA) and nasal cavity volumes (NCV) as measured by acoustic rhinometry (AR), and peak nasal inspiratory flow (PNIF). ENDS significantly increased the MCA and the NCV in the anterior 0.0-3.0 cm of the nose compared to DNS, but had no effect on MCA from 3.0 to 5.4 cm behind the nostrils. In contrast to DNS, ENDS had no effect on the posterior NCV. ENDS and DNS gave comparable increase in nasal inspiratory flow as measured by PNIF, and in the subject's own experience of nasal obstruction. ENDS may represent an alternative to DNS as a measure against nasal blockage.

Snow and ice concentrations of selected persistent pollutants in the Ob-Yenisey river watershed

As one of the largest river systems attached to the Arctic Basin, the Ob-Yenisey watershed has the potential to be a major supply route of persistent organic pollutants into marine ecosystems of the Arctic Ocean. Snowfall and ice formation taking place in the Ob-Yenisey river basin and shelf are key components of the system of processes responsible for the transfer of pollutants from this high latitude river to the adjacent Kara and Barents Seas. Here we examine a large data set on persistent organic pollutants in snow and ice determined for areas within the Ob (interior and coastal), Yenisey and adjacent shelf. Data on the levels of total oil hydrocarbons, as well as individual components for groups (PAHs, HCHs, CBs, DDTs, PCBs) were examined in this investigation for two time periods: winter (1992)-spring (1993) and winter (1993)-spring (1994). Spatial averaging of each data set for individual years was performed in order to identify large-scale geographical trends in contaminant distributions within the four regions. The analysis indicates that mean pollutant concentrations in snow are consistent throughout the watershed. Comparing data from 1992/1993 and 1993/1994, in all cases, concentrations do not vary appreciatively among the different regions. A similar finding was observed for concentrations of pollutants in ice. Persistent organic pollutants for the Ob-Yenisey watershed are in most cases not dissimilar to measurements carried out in the far north of Canada. The exception is summation operator DDT. Concentrations of this pollutant are an order of magnitude higher in the Ob-Yenisey watershed as compared to the Canadian Arctic (0.09 ng/l).

Congener specific PCB and polychlorinated camphene (toxaphene) levels in Svalbard ringed seals (Phoca hispida) in relation to sex, age, condition and cytochrome P450 enzyme activity

Congener specific PCB and toxaphene (polychlorinated camphene, PCC) analyses were performed in seal blubber, collected in Svalbard, Norway. The concentration, body burden and metabolic index (PCB congener concentration in seal relative to their prey) were calculated. Multiple regression analyses were carried out to evaluate the influence of age, sex, blubber (as a percentage of total body weight) and cytochrome P450 activities on PCB and PCC levels. Levels of total PCBs found were five times higher than in ringed seals from the Canadian Arctic, corresponding with the relatively high contaminant levels in the European Arctic. The dominant PCB congeners (> 70% of the total PCBs measured) were 153, 138, 99, 180 and 101. The observed PCB and PCC accumulation patterns were very similar to patterns in seals from other studies, suggesting a large resemblance in contaminant metabolism. A decrease in the relative abundance of the lower chlorinated PCBs, was associated with higher concentrations of PCB 153. Since there was no indication for selective PCB excretion by lactating females, this suggests metabolism of these PCBs in ringed seals due to xenobiotic metabolising enzymes. The metabolic index confirmed the model of persistency of the different PCBs except for congener 128 and 138. These congeners, considered persistent in seals, could to some extent be metabolised in ringed seals. However, co-elution of PCB 138 with PCB 163 and of PCB 128 with TOX 50 possibly has resulted in an underestimation of the metabolic index for these congeners. Multiple regression analyses revealed a significant positive effect of age and a negative effect of the blubber content on the PCB concentrations. Since large fluctuations of body lipids occur between seasons in pinnipeds, PCB measurements should account for the total blubber content to avoid biased results. PCBs with vicinal H-atoms in the o, m or the m, p positions showed in addition a relation with cytochrome P450 enzyme activities. Surprisingly, no effect of sex on the PCB concentrations was observed, probably because female ringed seals, unlike other pinnipeds, continue feeding during lactation. This results in only small amounts of lipid and lipid-associated contaminants being mobilised from the blubber. Consequently, contaminant excretion with the milk will be low. Toxaphene concentrations found were low compared to levels found in the Canadian Arctic. Two congeners, TOX 26 and TOX 50 were predominant (15 and 18%, respectively of total toxaphene). There was no effect of sex, age, total blubber, or cytochrome P450 activities on the toxaphene levels. There was also no correlation between toxaphene and PCB levels, which may indicate differences in exposure and metabolism between these contaminants. Toxaphenes did not bioaccumulate to any substantial extent in ringed seals.