A method for harvesting viable cells from wound dressings.

Wound fluid has been well studied for exploring protein biomarkers contained in it. However, cells in wound fluid have not received much attention due to the difficulty in their collection. Our study aimed to establish a method for collecting viable cells from discarded wound dressings. A protocol was designed to wash out nonadherent cells and detach adherent cells from silicone-faced foam wound dressings using trypsin-EDTA. The optimal concentration and incubation time of trypsin-EDTA for collecting equivalent proportions of different cell types to the original cell population were determined in vitro. Cell composition and gene expression changes in monocytes, lymphocytes, neutrophils, fibroblasts and keratinocytes were confirmed using immunocytochemistry and RNA-sequencing ex vivo. Full-thickness wounds were created on 9-week-old male C57BL/6J mice. Wound fluid was collected, and half of it was applied to the wound dressings. The original cell population in the wound fluid and the cell population collected from wound dressings were compared. In the in vitro study, 0.25% trypsin-EDTA and 2.5-min incubation time were considered optimal for collecting adherent cells from wound dressings. In the ex vivo study, among all cell types, only CD3+ lymphocytes showed a significantly higher cell proportion in the collected group. The relative gene expression of the five selected cells showed no significant changes (p-value >0.05, |log2 fold change| < 1.5, differential gene expression analysis). Viable nonadherent and adherent cells were collected from wound dressings without altering gene expression and could be used in future studies for cellular analysis of wound fluid.

Efficacy of wearable vibration dressings on full-thickness wound healing in a hyperglycemic rat model.

Local low-frequency vibration promotes blood flow and wound healing in hard-to-heal diabetic foot ulcers (DFUs). However, vibration treatment is challenging in patients with DFUs due to wound management difficulties and low adherence. Consequently, developing wearable self-care devices becomes imperative for effective wound healing. This study introduces a wearable vibration dressing and assesses its impact on wound healing in hyperglycemic rats. Low-frequency vibration at 52 Hz was applied to the wound for 40 min/day in awake rats. Relative wound areas on post-wounding days (PWDs) 4-7 were significantly smaller and the wound closure rate was significantly higher in the vibration group than in the control group (p < 0.05, respectively). The total haemoglobin at baseline and after vibration on post-wounding day 7 was significantly larger in the vibration group than in the control group (p < 0.05). On PWD 7, the thickness of the granulation tissue was significantly higher in the vibration group than in the control group (p < 0.05). Moreover, the number of blood vessels at the wound site and vascular endothelial growth factor A protein expression were significantly higher in the vibration group than in the control group (p < 0.05, respectively). The ratio of (CD68+ /iNOS+ )/(CD163+ ) macrophages in the vibration group was significantly lower than that in the control group (p < 0.05). These results indicate the potential of wearable vibration dressings as new self-care devices that can promote angiogenesis and blood flow, improve inflammation, and enhance wound healing in DFUs.

Relationship between healing status and microbial dissimilarity in wound and peri-wound skin in pressure injuries.

AIM: Wound infection is the most serious cause of delayed healing for patients with pressure injuries. The wound microbiota, which plays a crucial role in delayed healing, forms by bacterial dissemination from the peri-wound skin. To manage the bioburden, wound and peri-wound skin care has been implemented; however, how the microbiota at these sites contribute to delayed healing is unclear. Therefore, we investigated the relationship between healing status and microbial dissimilarity in wound and peri-wound skin. METHODS: A prospective cohort study was conducted at a long-term care hospital. The outcome was healing status assessed using the DESIGN-R® tool, a wound assessment tool to monitor the wound healing process. Bacterial DNA was extracted from the wound and peri-wound swabs, and microbiota composition was analyzed using 16S rRNA gene analysis. To evaluate microbial similarity, the weighted UniFrac dissimilarity index between wound and peri-wound microbiota was calculated. RESULTS: Twenty-two pressure injuries (7 deep and 15 superficial wounds) were included in the study. For deep wounds, the predominant bacteria in wound and peri-wound skin were the same in the healing wounds, whereas they were different in all cases of hard-to-heal wounds. Analysis based on the weighted UniFrac dissimilarity index, there was no significant difference for healing wounds (p = 0.639), while a significant difference was found for hard-to-heal wounds (p = 0.047). CONCLUSIONS: Delayed healing is possibly associated with formation of wound microbiota that is different in composition from that of the skin commensal microbiota. This study provides a new perspective for assessing wound bioburden.

An in vivo critically colonised wound model with dysbiotic wound microbiota.

In critically colonised wounds, many of the signs of infection are often absent, and delayed healing may be the only clinical sign. The prevention of critical colonisation is important, but its pathophysiology has not yet been elucidated. We have previously reported that dysbiotic microbiota dissimilar to the peri-wound skin microbiota may develop in critically colonised wounds. To investigate the role of dysbiotic microbiota, this study aimed to develop a critically colonised wound model by transplantation of dysbiotic microbiota. To transplant microbiota, a bacterial solution (dysbiosis group) or with Luria-Bertani medium (commensal group) was inoculated to full-thickness wounds of rats. The bacterial solution was prepared by anaerobically culturing bacteria from donor rats on an artificial dermis in Luria-Bertani medium for 72 hours. As a result, the degree of the change in the microbial similarity between pre- and post-transplantation of microbiota was significantly higher in the dysbiosis group (P < .001). No signs of infection were observed in any rat in either group. The wound area in the dysbiosis group was significantly larger (P < .001), and there was a significant infiltration of neutrophils (P < .001). All rats of the dysbiosis group represented the clinical features of critically colonised wounds. Furthermore, there were significantly fewer regulatory T cells in the wounds of the dysbiosis group. This is the first study to develop a novel animal model that represents the clinical features of critically colonised wounds and will be useful in investigating the pathogenesis of critical colonisation via regulatory T cells.

Development of a method to identify persistent and blanchable redness by skin blotting in mice.

Persistent and blanchable redness (PBR) is not currently included in category I pressure injury (PI), which is defined as non-blanchable redness (NBR). However, PBR progresses to PI in a clinical setting. Therefore, it should be clinically managed as category I PI, and a method to distinctly identify PBR is needed. This study aimed to examine whether PI-related biomarkers can distinguish PRB from transient redness (TR) and NBR using skin blotting. TR, PBR, and NBR models were established by the different conditions of dorsal skin compression. Redness observation and skin blotting were performed, and the skin tissue samples were subjected to histological and molecular biological analyses. The vascular endothelial growth factor (Vegf) b, heat shock protein (Hsp) 90aa1, tumour necrosis factor, interleukin (Il) 1b, and Il6 messenger ribonucleic acid levels were significantly different between the three models. The VEGF-A, VEGF-B, IL-1ß, and IL-6 protein levels were different between the three models. Although the results of skin blot examinations were inconsistent with those of the expression analysis of tissue, HSP90α and IL-1ß are suggested to be potential markers to distinguish PBR from TR and NBR.

Expression levels of NPPB, ITGB6, CPNE4, EML5, and ITSN1 in fresh exudates swabbed from critically colonised and infected full-thickness wounds in rats.

Pressure injury management requires reliable identification of critical colonisation due to lack of infection signs. Our research group previously proposed the mRNAs natriuretic peptide B (Nppb), integrin subunit beta 6 (Itgb6), copine 4 (Cpne4), echinoderm microtubule-associated protein like 5, and intersectin 1 as candidate markers in pooled exudates of critically colonised wounds. However, it is unclear whether mRNAs or proteins of the candidate genes would be suitable as biomarkers in fresh exudate. Therefore, this study aimed to evaluate the validity of the mRNAs and proteins as fresh exudate markers for critical colonisation. Three wound models of normal healing, critical colonisation, and infection were created in rats. Fresh swab-collected exudates were collected, and mRNA and protein expression levels were measured. In the fresh wound exudates, the detection frequency of Itgb6 tended to decrease in the critically colonised and infected wounds (P = .067), and those of Cpne4 and Nppb tended to be lower in the infected wounds than in the normal healing and critically colonised wounds (P = .006 and .067, respectively). In contrast, there was no difference in protein expression in the exudates. This study suggests that Itgb6 mRNA in fresh exudates is a promising biomarker for critical colonisation.

Bacterial invasion into the epidermis of rats with sodium lauryl sulphate-irritated skin increases damage and induces incontinence-associated dermatitis.

Incontinence-associated dermatitis (IAD) is caused by prolonged exposure to urine/liquid stool. It is a common and often painful skin condition in older incontinent adults because of poor prevention. Patients with urinary infections are at risk of developing IAD, and to guide the development of novel prevention strategies, we aimed to develop an animal model of IAD by urine and bacteria. First, contralateral sites on the dorsal skin of Sprague-Dawley rats were compromised by sodium lauryl sulphate (SLS), simulating frequent cleansing with soap/water. Filter discs were then placed inside ring-shaped chambers on foam dressings, inoculated with or without Pseudomonas aeruginosa, covered with agarose gels immersed in cultured filtrated urine, and secured in place with an occlusive dressing for 3 days. Untreated and SLS-compromised sites served as controls. The IAD was developed at bacteria-inoculated sites, characterised by severe IAD-like redness that persisted for up to 3 days post-exposure and higher disruption of the skin barrier function compared with non-inoculated sites. Pathological changes included epidermal thickening, partial skin loss, inflammatory cell infiltration, accumulation of red blood cells, and invasion of bacteria into the epidermis. This novel, clinically relevant IAD rat model can serve for future prevention developments.

Identification of microRNAs responsive to shear loading in rat skin.

Pressure injuries (PIs) are localised skin injuries that result from pressure with or without shear force. Shear force is more destructive than pressure in clinical settings. Therefore, determining the critical external forces is important for selecting the appropriate care to prevent PIs. To quantitatively distinguish pressure and shear loading with high specificity, we focused on microRNAs (miRs). This study aimed to identify the miRs that are distinguishable between pressure with and without shear loading in rat skin. Microarray analysis identified six candidate miRs from the comparisons among the pressure, shear, and unloaded groups. We analysed the expression levels of the candidate miRs in the process of PI development using real-time reverse transcriptase polymerase chain reaction. In the pressure and shear groups, miR-92b expressions at 6 hours after loading were 2.3 ± 1.3 and 2.9 ± 1.0, respectively, which were significantly higher than those in the control group (P = .014 and .004, respectively). miR-877 expression at 6 hours after loading was significantly increased only in the shear group (2.8 ± 0.9) compared with the control group (P = .016). These results indicate that miR-92b and miR-877 are promising biomarkers to determine for which external force healthcare professionals should intervene.

Polymorphism analysis of candidate risk genes for pressure injuries in older Japanese patients: A cross-sectional study at a long-term care hospital.

Advances in patient care for pressure injuries (PIs) have reduced the prevalence of PIs in Japan, although not in recent years. Several single-nucleotide polymorphisms (SNPs) have been identified in genes potentially associated with PIs. However, individual variance among PI risks require targeted investigations that may lead to the identification of PI susceptibilities or preventive care options that directly influence PI development pathways. This cross-sectional study examined the association between PIs and SNPs in genes related to tissue tolerance in patients in a long-term care hospital in Japan. A total of 178 participants (130 control, 20 with superficial PI history, and 28 with deep PI history) were enrolled in this study of eight SNPs in hypoxia inducible factor 1 subunit alpha (HIF1A), vascular endothelial growth factor C (VEGFC), heat shock protein 90 alpha family class A member 1 (HSP90AA1), myostatin (MSTN), and vitamin D receptor (VDR). The primary outcome was a history of superficial and deep PIs in the last 6 months. SNPs were examined by real-time polymerase chain reaction, followed by multivariate logistic regression analyses of the associations between the SNPs and PI history. The results showed a significant association between VEGFC rs1485766 and the history of superficial PIs (odds ratio = 2.95; 95% confidence interval = 1.07-8.11; p = 0.04). Stratified analysis using the Braden Scale (≤14) indicated a significant association between HIF1A rs11549465 and deep PIs (p = 0.04). Our study demonstrated that VEGFC rs1485766 and HIF1A rs11549465 were associated with superficial and deep PI susceptibilities, respectively.

A change in temporal muscle thickness is correlated with past energy adequacy in bedridden older adults: a prospective cohort study.

BACKGROUND: Energy inadequacy has a great impact on health outcomes in older adult patients; however, it is difficult to evaluate energy adequacy in these patients, especially in home-care settings. We recently reported that temporal muscle thickness can be an indicator of nutritional status. The present study aims to examine whether a change in temporal muscle thickness is directly correlated with energy adequacy and, if so, to determine the cutoff value of a change in temporal muscle thickness to detect energy inadequacy. METHODS: A prospective cohort study was conducted from September 2015 to June 2016 in two hospitals in Japan, and included bedridden older adult patients aged ≥65 years. Temporal muscle thickness was measured using ultrasonography. Energy intake was estimated by photographic diet records. Total energy expenditure (TEE) was estimated by multiplying basal energy expenditure calculated using the Harris- Benedict equation by activity and stress factors. Energy adequacy was then calculated by dividing TEE by energy intake. Pearson's correlation coefficient was used to examine the relationship between percentage change in temporal muscle thickness and energy adequacy. Multiple logistic regression analysis was conducted to determine the direct relationship between percentage change in temporal muscle thickness and moderate energy inadequacy (energy adequacy< 75%). Receiver operating characteristic (ROC) analysis was performed to determine the cutoff point for percentage change in temporal muscle thickness to detect moderate energy inadequacy. RESULTS: Forty-eight patients were analyzed (mean age 84.4 ± 7.8 years; 54.2% were women). The percentage change in muscle thickness was significantly correlated with energy adequacy (r = 0.733, p < 0.001). ROC analysis identified a percentage change in temporal muscle thickness of - 3.6% as the optimal cutoff point for detecting moderate energy inadequacy. Percentage change in muscle thickness was independently correlated with energy inadequacy after adjusting for age, sex, and masticatory status (AOR 0.281, 95% CI 0.125-0.635). CONCLUSIONS: Changes in temporal muscle thickness are directly correlated with energy adequacy and can indicate moderate energy inadequacy in bedridden older adults. These results suggest the assessment of changes in temporal muscle thickness could be useful for guiding nutritional care in older adult patients in home-care settings.

Promoting effect of acylated homoserine lactone on the healing of tissue damage in model rats with incontinence-associated dermatitis.

OBJECTIVE: One of the most common complications in patients with incontinence is incontinence-associated dermatitis (IAD). This study was conducted to determine the pathophysiology of the healing process of IAD and to develop an effective therapeutic approach according to its pathophysiology. METHOD: IAD was reproduced on a dorsal rat skin by applying agarose gel containing water and enzymes, and inoculating it with bacteria. Examination of the IAD healing process suggested that the promotion of keratinocyte migration and improvement of basement membrane enhance keratinocyte layer elongations, which contribute to IAD healing. A therapeutic approach using N-(3-oxotetradecanoyl)-L-homoserine lactone, which is one of the acylated homoserine lactones (AHLs) and can promote keratinocyte migration in vitro, was applied on the IAD area in rats. RESULTS: AHL treatment after IAD development resulted in an earlier tipping point for recovery than the vehicle treatment. Histological and immunohistological analyses revealed that the tissue surface was already covered by the epidermis, indicating the results of elongation of the keratinocyte layer from hair follicles. The characteristics of the alignment of basal keratinocytes, the existence of stratum corneum, and the membrane-like distribution of the components of basement membrane were similar to those of a normal epidermis. CONCLUSION: These results suggested that AHL application possibly contributed to earlier IAD healing before progressing to a severe state. Although elongation of the keratinocyte layer was observed in both the AHL and vehicle groups, the possibility that AHL application promotes IAD healing was suggested. The new concept of the enhancement of keratinocyte migration as a therapeutic approach for IAD would change the skin care strategy for IAD in the healthcare setting.

Concurrent validity of biofilm detection by wound blotting on hard-to-heal wounds.

OBJECTIVE: Wound biofilms delay healing of hard-to-heal wounds. Convenient biofilm identification tools for clinical settings are currently not available, hindering biofilm-based wound management. Wound blotting with biofilm staining is a potential tool for biofilm detection, owing to its convenience. Although predictive validity of wound blotting has been established, it is necessary to confirm its concurrent validity. Furthermore, current staining systems employing ruthenium red have some disadvantages for clinical use. This study aimed to evaluate the usability of alcian blue as a substitute for ruthenium red. METHOD: Both in vitro and in vivo clinical samples were used to investigate validity and usability. RESULTS: The in vitro study showed that proteins and extracellular DNA in biofilms did not affect staining ability of ruthenium red and alcian blue in the detection of biofilms. In the in vivo study, using a wound biofilm model with Pseudomonas aeruginosa, the staining sensitivity of ruthenium red was 88.9% and 100% for alcian blue, with correlation coefficients of signal intensities with native polyacrylamide gel electrophoresis (PAGE) of r=0.67 (p=0.035) and r=0.67 (p=0.036) for ruthenium red and alcian blue, respectively. Results from clinical samples were r=0.75 (p=0.001) for ruthenium red and r=0.77 (p<0.001) for alcian blue. The sensitivities of wound blotting staining by ruthenium red and alcian blue were very high and had a good correlation with native PAGE analysis. CONCLUSION: Because the alcian blue procedure is more convenient than the ruthenium red procedure, wound blotting with alcian blue staining would be a promising tool to guide clinicians in delivering biofilm-based wound management.

Does the presence of bacterial urinary infection contribute to the development of incontinence-associated dermatitis? A scoping review.

OBJECTIVE: Incontinence-associated dermatitis (IAD) is an inflammatory skin condition caused by the repeated exposure to urine and faeces. It is not common for urinary incontinence only to cause IAD, however patients with urinary tract infections (UTIs) are also at increased risk for IAD. This scoping review aimed to provide a summary of the relationship between bacterial urinary infections and IAD. METHODS: We conducted a scoping review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. PubMed, CINAHL, Medline, and Web of Science were searched for relevant articles from January 2007 through February 2020. RESULTS: Based on eligibility criteria, 13 research studies and review articles were included. Despite the acknowledged role of bacterial infections can play in IAD and the importance of eradicating infections for the prevention of skin breakdown, there have been limited studies that have investigated how uropathogenic bacteria, in combination with urine, lead to skin damage and IAD. The use of urinary catheters also predisposes to UTIs; however, prevalence/incidence rates of IAD in these patients are not clear, as they were considered as continent of urine in the included studies. CONCLUSION: Further research is needed to elucidate the mechanisms of how bacteria, in combination with urine, lead to IAD.

Validity of skin blot examination for albumin and nerve growth factor ß to detect itching of the skin in Indonesian older adults.

AIM: Itching, a common skin disorder, impacts the quality of life of individuals. Itchy skin occurs more with increasing age and the prediction of itchy skin prognosis is necessary to provide good skincare. This study validated biomarkers in skin blotting to identify and measure itching sensation as well as conventional methods to measure skin barrier function. MATERIALS AND METHODS: From a cross-sectional study conducted in Long-term Care (LTC) facilities in Indonesia itching symptoms were obtained through a questionnaire. Skin conditions were assessed using photographs, stratum corneum (SC) hydration, skin pH, and skin blotting for biomarkers: albumin, interleukin 2 (IL2), nerve growth factor ß (NGFß), and thymic stromal lymphopoietin (TSLP). Association of skin measurements with the presence of skin blotting and trends analysis were conducted. RESULTS: Altogether, 564 LTC residents (average age, 70 years) participated. The SC hydration, skin pH, albumin, and NGFß were associated with the presence of itch (p value= <0.001, <0.001, <0.001, and <0.001, respectively). The signal levels of skin blotting biomarkers were higher in itch group than in the non-itch group. Additionally, the higher quantile of SC hydration was significantly associated with a lower intensity level of NGFß and TSLP (p value = 0.005, 0.003, respectively). The lower quantile of skin pH (better skin condition) was significantly associated with lower albumin, NGFß, and TSLP (p value = 0.048, 0.035, and <0.001, respectively). CONCLUSION: The albumin, NGFß, and TSLP could be a candidate for measurement of itchy skin among older adult with disrupted skin barrier function and local skin inflammation.

Risk scoring tool for forearm skin tears in Japanese older adults: A prospective cohort study.

[Aim] Because painful skin tears frequently occur in older patients, the prevention of skin tears is fundamental to improve their quality of life. However, a risk assessment tool for skin tears has not been established yet in Japan. Therefore, we aimed to propose a risk scoring tool for skin tears in Japanese older adult. [Methods] We conducted a prospective cohort study with 6-month follow-up in two long-term care hospitals in Japan. A total of 257 inpatients were recruited. Patient and skin characteristics were collected at baseline, and the occurrence of forearm skin tears were examined during follow-up. To develop a risk scoring tool, we identified risk factors, and converted their coefficients estimated in the multiple logistic regression analysis into simplified scores. The predictive accuracy of the total score was evaluated. [Results] Of 244 participants, 29 developed forearm skin tears during the follow-up period, a cumulative incidence of 13.5%. Senile purpura, pseudoscar, contracture, and dry skin were identified as risk factors for skin tears. Their weighted scores were 6, 4, 5, and 6, respectively. The area under the receiver operating characteristic curve of the total score was 0.806. At a cut-off score of 12, the sensitivity was 0.86, and the specificity was 0.67. [Conclusion] Our forearm skin tear risk scoring tool showed high accuracy, whereas specificity was low. This tool can contribute to prevent forearm skin tears in Japanese older adults.

The relationship between skin ultrasound images and muscle damage using skin blotting in wheelchair basketball athletes.

STUDY DESIGN: Secondary analysis of a cross-sectional observation study. OBJECTIVES: To determine the relationship between skin ultrasound images and muscle damage in wheelchair basketball athletes, using skin blotting examinations of the ischial regions. SETTING: Community, Japan. METHODS: Fourteen elite wheelchair basketball athletes were recruited. We obtained data regarding participants' characteristics. We undertook ultrasonographic images and quantitative skin blotting of the ischial region before and after training, and after rest. RESULTS: We identified Category II and III pressure injuries in 2 of the 12 participants. Structural features were classified into four categories based on ultrasonographic features, namely, normal skin structure, unclear superficial and deep fascia, cloudy fat layer, and fat infiltration and low-echoic lesion/anechoic lesions. The muscle-type creatinine kinase (CK-M) level (median [interquartile range: IQR], 2.98 [2.80-3.47]) in the fat infiltration and low-echoic lesion/anechoic lesion group was significantly higher (1.43 [1.41-1.49]) than in a nonfat infiltration and low-echoic lesion/anechoic lesion group after training (p = 0.03). The interleukin-6 (IL-6) level (median [IQR], 23.5 [16.15-58.97]) in the fat infiltration and low-echoic lesion/anechoic lesion group was significantly higher (1.94 [1.74-4.44]) than in the nonfat infiltration and low-echoic lesion/anechoic lesion group after rest (mean difference = -25.4, 95% CI -61.1 to 10.7, p = 0.03). CONCLUSIONS: The combination of ultrasonographic images and skin blotting using CK-M and IL-6, could detect early deep tissue damage in wheelchair athletes. These techniques could be potentially useful in the treatment and prevention of pressure injuries. SPONSORSHIP: This study was supported in part by YAMAHA Motor Foundation for Sports.

Development of recurrent pressure ulcers, risk factors in older patients: a prospective observational study.

OBJECTIVE: Prevention of recurrent pressure ulcers (PU) is one of the most important challenges in wound care, furthermore, the risk factors for recurrent PUs are still not fully understood. This study aimed to explore the risk factors for recurrent PU development within two weeks, including biophysical skin properties, pro-inflammatory cytokine (tumour necrosis factor [TNF]-α) levels and bacterial species, in older patients. METHOD: This prospective study was conducted in a long-term care facility with patients whose PU had healed within two months. Biophysical skin properties were evaluated by stratum corneum hydration, pH, sebum content and transepidermal water loss. TNF-α level was measured using skin blotting. Skin bacteria were collected using tape stripping and determined by species-specific gene amplification. These parameters, along with Braden scale and interface pressure, were evaluated every two weeks for a total period of eight weeks. A penalised generalised estimating equation analysis was used to determine the risk factors for recurrent PUs. RESULTS: In total, 20 patients were included in this study, with 57 observations. Of these, recurrent PU was seen in eight observations. Elevation of pH (p=0.049; odds ratio [OR] per 1 unit=3.91, 95% confidence interval [CI]:1.01-15.15), presence of Acinetobacter spp. (p=0.039; OR versus culture-negative=6.28, 95%CI:1.10-35.86) and higher interface pressure (p=0.008; OR per 1 mmHg=1.06, 95%CI:1.01-1.10) on the healed PU were significantly related to the development of recurrent PU. CONCLUSION: Higher pH, existence of Acinetobacter spp. and higher interface pressure on the site of the healed PU were associated with the development of recurrent PUs in older patients undergoing conservative treatments.

Non-invasive detection of local tissue responses to predict pressure ulcer development in mouse models.

The development of pressure ulcers is associated with four different pathways: ischemia, ischemia-reperfusion injury, impaired interstitial fluid flow and lymphatic drainage, and cell deformation. For prediction of pressure ulcer development, it is important to detect the tissue response involved in the pathways at the molecular level. However, non-invasive techniques for detecting this tissue response are not available. This study aimed to demonstrate that the secretion of the candidate marker proteins in pressure-loaded mouse skin can be detected by skin blotting, and to propose a novel direct skin assessment method for predicting pressure ulcer development. We created three different tissue damage models: early stage pressure ulcers, blanchable erythema and intact skin. We confirmed the pathways involved in the pressure ulcer development by histological analyses in the pressure ulcer model. Interleukin-1α (IL-1α), vascular endothelial growth factor C (VEGF-C) and heat shock protein 90α (HSP90α) were expressed in the pressure ulcer model at a significantly different level compared to the blanchable erythema or intact skin during the time course. Detecting the secretion of these novel biomarkers by skin blotting can be a useful method for non-invasive prediction of pressure ulcer development.

Skin characteristics associated with foot callus in people with diabetes: A cross-sectional study focused on desmocollin1 in corneocytes.

AIM: The purpose of this study was to investigate the degradation of desmocollin-1 (DSC1), a member of the desmosomal cadherin family in patients with diabetes, as well as the factors associated with the suppression of DSC1 degradation. METHODS: This cross-sectional study included 60 cases of foot callus involving 30 patients with diabetes (DM) and 30 matched volunteers without diabetes (non-DM). DSC1 degradation in samples from debrided calluses was analysed using western blotting. Skin hydration, a factor reported to suppress DSC1 degradation, was measured using a mobile moisture device. RESULTS: Full-length DSC1 (approximately 100 kDa) was detected in six participants only in the DM group, and no relationship was found between the suppression of DSC1 degradation and decreased skin hydration in the DM group. There was no significant difference in skin hydration values between the DM and non-DM groups. CONCLUSION: DSC1 degradation was suppressed in the DM group. There was no relationship between the suppression of DSC1 degradation and decreased skin hydration in the DM group. Current external force callus care would not be sufficient. This study highlights the need to develop novel callus care to enhance the degradation of DSC1.

Combination of urease inhibitor and antiseptic inhibits urea decomposition-induced ammonia production by Proteus mirabilis.

The decomposition of urea into ammonia by urease-producing bacterium shows an elevation in the pH level, which can lead to incontinence-associated dermatitis (IAD). This study aimed to examine the efficacy of a combination of antiseptic and urease inhibitor in inhibiting the decomposition of urea by the urease-producing bacterium Proteus mirabilis. We performed in vitro assays to compare the effects of a combination of antiseptic and urease inhibitor, antiseptic only, urease inhibitor only, and an untreated control with the effects of a urea-containing solution. Cultured P. mirabilis was mixed with urea-containing solution, followed by the addition of antiseptic and/or urease inhibitor. The main outcome used to assess the efficacy of the different treatments was ammonia concentration at 4-hours post-treatment initiation, and multiple comparison analysis was performed using Dunnett's test to compare the results between groups. Ammonia concentrations in samples treated with either antiseptic or urease inhibitor were lower than those in the untreated control, while the combination of antiseptic and urease inhibitor resulted in decreased ammonia concentrations compared with either treatment alone. Therefore, the application of both urease inhibitor and antiseptic is more effective for the inhibition of urea decomposition by urease-producing bacteria. Novel preventive strategies using these reagents may be effective for preventing IAD.