Mikako Yoshida

Hypo-osmotic Shock-Induced Subclinical Inflammation of Skin in a Rat Model of Disrupted Skin Barrier Function

Aging disrupts skin barrier function and induces xerosis accompanied by pruritus. In many cases, elderly patients complain of pruritus during skin hygiene care, a condition called aquagenic pruritus of the elderly (APE). To date, the pathophysiology and mechanism of action of APE have not been elucidated. We conducted the present study to test the hypothesis that hypo-osmotic shock of epidermal cells induces skin inflammation and elongation of C-fibers by nerve growth factor β (NGFβ) as a basic mechanism of APE. The dorsal skin of HWY rats, which are a model for disrupted skin barrier function, was treated with distilled water (hypotonic treatment [Hypo] group) or normal saline (isotonic treatment [Iso] group) by applying soaked gauze for 7 days. Untreated rats were used as a control (no-treatment [NT] group). Histochemical and immunohistochemical analyses revealed inflammatory responses in the epidermis and the dermal papillary layer in the Hypo group, while no alterations were observed in the Iso or NT groups. Induction of expression and secretion of NGFβ and elongation of C-fibers into the epidermis were found in the Hypo group. In contrast, secretion of NGFβ was significantly lower and elongation of C-fibers was not observed in the Iso group. These results suggest that hypo-osmotic shock–induced inflammatory reactions promote hypersensitivity to pruritus in skin with disrupted barrier function.

Compression-induced HIF-1 enhances thrombosis and PAI-1 expression in mouse skin.

Pressure ulcers result from tissue hypoxia caused by external forces. Thrombosis due to external forces is considered important, and hypoxia inducible factor‐1 (HIF‐1) is a master regulator of pressure ulcer development. To date, however, their causal relationship has not been determined. This study therefore investigated the mutual relationship between thrombosis and HIF‐1 activation in compressed mouse skin, based on a hypothesis that HIF‐1 regulation by plasminogen activator inhibitor‐1 (PAI‐1) enhances thrombosis. Compression of mouse skin significantly increased the numbers of thrombi and HIF‐1α‐positive cells compared with control skin. A thrombosis inhibitor significantly reduced the numbers of HIF‐1α‐positive cells and an HIF‐1 inhibitor significantly inhibited thrombosis in compressed skin tissue, suggesting a mutual relationship between thrombosis and HIF‐1 activation. Compression of mouse skin also enhanced the level of Pai‐1 messenger RNA expression, but this increase was significantly reduced by treatment with an HIF‐1 inhibitor, whereas a thrombosis inhibitor had no effect. These results suggested the involvement of PAI‐1 in HIF‐1‐enhanced thrombosis and that an additional factor participates in regulating Pai‐1 expression in compressed skin. These findings may suggest new strategies in pressure ulcer management.

Differences in motor learning of pelvic floor muscle contraction between women with and without stress urinary incontinence: Evaluation by transabdominal ultrasonography

To evaluate differences in motor learning of pelvic floor muscle (PFM) contraction between women with and without stress urinary incontinence (SUI) under transabdominal ultrasonography (TAUS)‐guided PFM training.

Translation and reliability and validity testing of a Japanese version of the Intermittent Self‐Catheterization Questionnaire among disposable and reusable catheter users

Quality of life in the context of intermittent self‐catheterization varies depending on the type of catheter used. This study translated into Japanese, evaluated the feasibility, reliability, and validity of the Intermittent Self‐Catheterization Questionnaire (ISC‐Q) among users of both reusable and disposable catheters, and examined the differences of it between them.

Inter-rater and intra-rater reliability outcomes of a rapid bacteria counting system with pressure ulcer samples

OBJECTIVE Evaluating bacterial load in pressure ulcers (PUs) is key to combat infection; therefore, using technologies to measure bacterial count can be particularly useful. A rapid bacteria counting system was recently developed and introduced to the wound care field. However, its reliability was not established. This cross-sectional study aimed to evaluate the inter-rater and intra-rater reliability of bacterial count using this rapid counting system. METHOD We took bacterial swabs from patients with category I or greater PUs to assess inter- and intra-rater reliability. An assessor swabbed the longest axis of the PU once and bacterial counts were measured using a rapid bacteria counting system. To confirm the inter-rater and intra-rater reliability, intraclass correlation coefficients (ICCs) were calculated. RESULTS We took 63 and 57 pairs of bacterial counts from 13 patients with 16 category I or greater PUs to assess inter- and intra-rater reliability, respectively. Overall ICCs [95% confidence intervals (CI)] for the bacterial counts were 0.83 [0.73-0.90, p<0.001, inter-rater reliability, n=63], and 0.89 [0.82-0.94, p< 0.001, intra-rater reliability, n=57]. CONCLUSION A high level of reliability for counting bacterial numbers in PU sites was confirmed. The results should encourage clinicians and researchers to use this type of device for the real-time assessment of wound bacterial bioburden at the patients bedside.

Clustering and classification of local image of wound blotting for assessment of pressure ulcer

This paper describes applying image recognition techniques to the stained image captured by wound blotting. The wound blotting adsorbs the proteins on the wound surface and visualizes protein distribution as a stained image. The local patterns of the stained image may indicate wound healing. For investigation of relationship between pressure ulcer healing process and protein distribution, the categorization and classification by image recognition technique are required because manual classification and annotation are time-consuming and troublesome. In order to apply clustering and classification to the stained image, three features (GLCM, wavelet, and LBP) were compared. As for the clustering, three features achieved the similar performance, however, the clustering results were slightly different from human labeling. As for the classification, wavelet and LBP features achieved good performance. However, particular texture pattern, which is defined as texture whose intensity was stable or changed on direction, was difficult to classify. These results demonstrated the feasibility of applying image recognition technique to the stained images for wound assessment.

Microsatellite polymorphism in the Heme oxygenase-1 gene promoter is associated with dermal collagen density in Japanese obese male subjects

We previously reported elevated oxidative stress-related mechanical vulnerabilities of the skin as sparse distributions of hyperechoic areas. Although this helped establish a personalized skin care system to prevent skin disorders related to mechanical stress, obesity-related skin vulnerability involves individual differences. Here, we hypothesized that individual differences are caused by polymorphisms of GT repetitive sequences in the heme oxygenase1 (HMOX1) promoter region, which encodes an antioxidant enzyme. This cross-sectional study enrolled healthy male volunteers in a walking classroom aimed at weight control. Subjects with a body mass index <25 kg/m2 were classified as non-obese and those with body mass index ≥25 kg/m2 were classified as obese. Subject skin was categorized into sparse dermis or normal groups according to the distribution of hyperechoic areas by high-resolution skin ultrasonography (20 MHz). Genomic DNA and mRNA extracted from three body hairs with attached follicle cells were used to analyze GT repetitive sequences of the HMOX1 promoter, HMOX1 mRNA expression levels, and oxidative stress levels (8-hydroxy-2’-deoxyguanosine). Classifications of GT repetitive sequence of HMOX1 promoter were Short (<27 times) and Long (≥27 times). Higher numbers of subjects with sparse dermis were in the obese group compared with the non-obese group. In obese subjects, the number of subjects that had the Long allele of the HMOX1 promoter with sparse dermis was significantly higher compared with the normal group, whereas no association was observed between the polymorphism and ultrasonographic features in non-obese subjects. Thus, HMOX1 polymorphisms detected a risk of low collagen density in Japanese obese male subjects.

Fecal Distribution Changes Using Colorectal Ultrasonography in Older People with Physical and Cognitive Impairment Living in Long-Term Care Facilities: A Longitudinal Observational Study

Nurses encounter difficulties evaluating constipation in elderly people with physical and cognitive impairment. Transabdominal ultrasonography (US) has been used to evaluate fecal impaction or fecal quality. However, it is unclear whether colorectal US can evaluate constipation symptoms in older people. Using colorectal US, we continuously observed the elderly and clarified the relationship between patterns of fecal distribution changes and constipation symptoms in older people with physical and cognitive impairment at long-term care facilities. This study included patients aged ≥65 years with oral intake. US was performed once a day until the next defecation, and fecal hardness was assessed. US images were extracted and categorized. Then, patterns of fecal distribution changes in the colorectum were classified. Multiple logistic regression analysis was performed to examine related factors associated with a constipation pattern. Among 101 patients, US images of 95 patients were analyzed. In 74.4% of the patients, US showed continuation of reflection with acoustic shadow in the rectum, which was significantly associated with defecation on the bed. Of the patients with a continuous crescent-shaped reflection pattern (R3), 92.9% had hard stool. R3 was found to be significantly associated with a Mini-Mental State Examination score of ≤10. In most of the patients, US detected a continuation of reflection with acoustic shadow in rectal patterns, indicating fecal retention in the rectum. Point-of-care US can be used by nurses to visualize rectal fecal retention as constipation patterns in the older people with physical and cognitive impairment at long-term care facilities.

Ultrasound-assisted prompted voiding for management of urinary incontinence of nursing home residents: Efficacy and feasibility

To assess the efficacy and feasibility of ultrasound‐assisted prompted voiding for the management of urinary incontinence in nursing homes.

Prediction of healing progress of pressure ulcers by distribution analysis of protein markers on necrotic tissue: A retrospective cohort study

Predicting the short‐term healing progress of pressure ulcers is important for providing timely and appropriate intervention. Although there are some prediction methods available, these are unsuitable for ulcers with abundant necrotic tissue. We aimed to elucidate the relationship between necrotic tissue alteration and protein distributions on ulcers to establish a new prediction method. Thirty‐eight pressure ulcers were retrospectively analyzed. Protein distributions on necrotic tissue were evaluated by the wound blotting at three levels: marker protein positivity, signal patterns (speckled, heterogeneous, or homogeneous), and the occupation of heterogeneous pattern. Peroxidase, alkaline phosphatase, tumor necrosis factor α, and matrix metalloproteinase‐2 were used as marker proteins. One‐week necrotic tissue alteration was classified as liquefaction or nonliquefaction, and associations with protein distributions were analyzed. The peroxidase positivity was significantly higher in the liquefaction than in the nonliquefaction (p = 0.031). In peroxidase‐positive samples, the proportion of nonliquefaction samples was significantly higher in the heterogeneous pattern (p = 0.029). In the heterogeneous‐patterned samples, the proportion of samples with an occupation values greater than the median value tended to be higher in the nonliquefaction (p = 0.087). There was no significant relationship between liquefaction and other markers. Peroxidase positivity predicts 1‐week liquefaction of necrotic tissue, while a heterogeneous pattern indicates nonliquefaction.