Fractal photonic bandgap fibers.

Photonic bandgap fibers have a critical constraint determined by wavelength. The principle of scale invariance requires that features remain unchanged even as the scale of an object changes. This paper introduces a new concept for fractal photonic crystal fibers integrating these two. Our simulation confirmed single-mode transmission is possible for a fiber whose core diameter exceeds 35 times the wavelength.

Real-time observation of the photoionization-induced water rearrangement dynamics in the 5-hydroxyindole-water cluster by time-resolved IR spectroscopy.

Solvation plays an essential role in controlling the mechanism and dynamics of chemical reactions in solution. The present study reveals that changes in the local solute-solvent interaction have a great impact on the timescale of solvent rearrangement dynamics. Time-resolved IR spectroscopy has been applied to a hydration rearrangement reaction in the monohydrated 5-hydroxyindole-water cluster induced by photoionization of the solute molecule. The water molecule changes the stable hydration site from the indolic NH site to the substituent OH site, both of which provide a strongly attractive potential for hydration. The rearrangement time constant amounts to 8 ± 2 ns, and is further slowed down by a factor of more than five at lower excess energy. These rearrangement times are slower by about three orders of magnitude than those reported for related systems where the water molecule is repelled from a repulsive part of the interaction potential toward an attractive well. The excess energy dependence of the time constant is well reproduced by RRKM theory. Differences in the reaction mechanism are discussed on the basis of energy relaxation dynamics.

Can Wound Exudate from Venous Leg Ulcers Measure Wound Pain Status?: A Pilot Study.

We investigated the associations between the self-evaluated pain status and two pain biomarker candidates, nerve growth factor and S100A8/A9, in exudate from venous leg ulcer to finally develop an objective pain evaluation method. Patients with venous leg ulcer participated in this cross-sectional observational study conducted between April and October 2014 at two medical facilities. During routine wound care, each participant self-evaluated their pain status at each examination using the 10-point numerical rating scale (present pain intensity) and the short-form McGill Pain Questionnaire 2 (continuous pain, intermittent pain, neuropathic pain, affective descriptors, and total score). Venous leg ulcer exudate sample was collected after wound cleansing. The nerve growth factor and S100A8/A9 concentrations in the venous leg ulcer exudate were measured by enzyme-linked immunosorbent assay and standardized according to the wound area. The association between each pain status and the two standardized protein concentrations was evaluated using Spearman's correlation coefficient. In 30 sample collected from 13 participants, the standardized nerve growth factor concentration was negatively correlated with continuous pain (ρ = -0.47, P = 0.01), intermittent pain (ρ = -0.48, P = 0.01), neuropathic pain (ρ = -0.51, P = 0.01), and total score (ρ = -0.46, P = 0.01). The standardized S100A8/A9 concentration was positively correlated with present pain intensity (ρ = 0.46, P = 0.03) and continuous pain (ρ = 0.48, P = 0.03). Thus, these two proteins may be useful for objective evaluation of wound pain in venous leg ulcer patients.

Trapped Hydronium Radical Produced by Ultraviolet Excitation of Substituted Aromatic Molecule.

The gas phase structure and excited state dynamics of o-aminophenol-H2O complex have been investigated using REMPI, IR-UV hole-burning spectroscopy, and pump-probe experiments with picoseconds laser pulses. The IR-UV spectroscopy indicates that the isomer responsible for the excitation spectrum corresponds to an orientation of the OH bond away from the NH2 group. The water molecule acts as H-bond acceptor of the OH group of the chromophore. The complexation of o-aminophenol with one water molecule induced an enhancement in the excited state lifetime on the band origin. The variation of the excited state lifetime of the complex with the excess energy from 1.4 ± 0.1 ns for the 0-0 band to 0.24 ± 0.3 ns for the band at 0-0 + 120 cm(-1) is very similar to the variation observed in the phenol-NH3 system. This experimental result suggests that the excited state hydrogen transfer reaction is the dominant channel for the non radiative pathway. Indeed, excited state ab initio calculations demonstrate that H transfer leading to the formation of the H3O(•) radical within the complex is the main reactive pathway.

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.

Synthesis of new 5-substituted hydantoins and symmetrical twin-drug type hydantoin derivatives.

In connection with our studies on hydantoin derivatives, a conventional regioselective chemical transformation of 5-methylene hydantoins 4a-c to 5-aminomethyl-substituted hydantoins 5-10 or to 5-amino-5-methyl-disubstituted hydantoins 11-14 is described. Synthesis of bivalent twin-drug type hydantoin derivatives 19-24 and the binding property of a bivalent symmetrical hydantoin derivative 24b to sulfated glycosaminoglycans are also described.

The reliability and validity of color indicators using digital image analysis of peristomal skin photographs: results of a preliminary prospective clinical study.

Accurate assessment is necessary to evaluate peristomal skin condition, but objective methods are lacking. The purpose of this prospective, repeated-measures study was to evaluate the reliability and validity of color indicators using digital image analysis of peristomal skin photographs. The 6-month study was conducted among 21 patients (mean age 65.1 years old, 15 men) with ostomies (14 colostomies, six ileostomies, and one urostomy) at four outpatient clinics. Photographs taken by nurses of the peristomal area using point-and-shoot cameras were processed using digital image analysis, which involved color calibration, image processing, and indicator calculation. An erythema index (EI), melanin index (MI), and hypopigmentation index were created to represent increased degrees of red, black, and white color, respectively, and their average values in the peristomal region of an image were calculated relative to values for intact skin. Reproducibility was evaluated using the interclass correlation coefficient (ICC). ICCs of color indicators for intact skin were >0.7 between baseline and the end of follow-up for the 16 participants with two or more clinic visits. Differences in these indices between peristomal and intact regions were evaluated using a linear mixed model. The EI and MI of peristomal skin were significantly higher than those of intact skin (n=42, P<0.001). All color indicators in adjacent regions and areas where adhesive was applied were associated with the discoloration severity score and visual analogue pain score (all P<0.05). This objective and simple method had adequate reproducibility and criterion-related validity and may be useful for peristomal skin assessment. Further research is warranted.

Visualization of Tumor Necrosis Factor-α Distributions Within Pressure Ulcer Tissue Using the Wound Blotting Method: A Case Report and Discussion.

Wound blotting can be used to visualize the protein distribution on a wound bed through protein collection by attaching a nitrocellulose membrane to the wound surface. This study checked for consistency between the protein distributions determined by wound blotting and those determined by removal of the tissue. A patient who was planning to undergo surgical debridement of an ulcer in the sacral region that was caused by lying down for a long period after a cerebral hemorrhage was recruited in Fujisawa City Hospital, Kanagawa, Japan. Wound blotting was performed just prior to surgical debridement and the debrided tissue embedded in paraffin. The ulcer, which had a 2.9 cm major axis, was divided into 20 areas approximately 0.35 cm2 each, and the consistency of tumor necrosis factor-α positivity between the wound blotting samples and tissue sections was examined in each area. The sensitivity and specificity of wound blotting were 89% and 82%, respectively. This wound blotting method noninvasively revealed the protein distributions within the wound tissue.

Morphological characteristics of and factors related to moisture-associated dermatitis surrounding malignant wounds in breast cancer patients.

PURPOSE: Patients with malignant breast wounds (MBWs) have multiple symptoms. In particular, care for exudates or peri-wound moisture-associated dermatitis (MAD) is difficult. However, MAD has not been distinguished from peri-wound dermatitis. Therefore, care for patients with MAD has not been well established. The aim of this study was to describe morphological characteristics of MAD in MBWs and link morphological characteristics of MAD to related factors. METHODS: We conducted a qualitative descriptive study and a cross-sectional study. Data were collected by qualitative participant observation and structured interviews. The qualitative descriptive study was conducted using the 'morphoqualitative analysis' method. Data analyses were performed using qualitative research methods. In the cross-sectional study, the participants were classified into 2 groups for comparison: with MAD (MAD group) and without MAD (non-MAD group). RESULTS: Characteristics of 24 MBWs were examined. Morphoqualitative analyses of data generated 17 subcategories and 3 categories. We could morphologically define MAD by findings of 'radial shape matching the dressing' and 'half-fusiform shape over the dressing'. Regarding factors related to MAD, necrotic tissue type was significantly more severe in the MAD group than in the non-MAD group (p = 0.048). Wound exudate leakage was significantly more frequent in the MAD group than in the non-MAD group (p = 0.013). CONCLUSION: Our study provides several points for nursing MBWs. Morphoqualitative analyses of MAD are quite important for evaluating possible causes of MAD as well as selecting effective interventions.

Predictive validity of granulation tissue color measured by digital image analysis for deep pressure ulcer healing: a multicenter prospective cohort study.

This multicenter prospective cohort study examined the predictive validity of granulation tissue color evaluated by digital image analysis for deep pressure ulcer healing. Ninety-one patients with deep pressure ulcers were followed for 3 weeks. From a wound photograph taken at baseline, an image representing the granulation red index (GRI) was processed in which a redder color represented higher values. We calculated the average GRI over granulation tissue and the proportion of pixels exceeding the threshold intensity of 80 for the granulation tissue surface (%GRI80) and wound surface (%wound red index 80). In the receiver operating characteristics curve analysis, most GRI parameters had adequate discriminative values for both improvement of the DESIGN-R total score and wound closure. Ulcers were categorized by the obtained cutoff points of the average GRI (≤80, >80), %GRI80 (≤55, >55-80, >80%), and %wound red index 80 (≤25, >25-50, >50%). In the linear mixed model, higher classes for all GRI parameters showed significantly greater relative improvement in overall wound severity during the 3 weeks after adjustment for patient characteristics and wound locations. Assessment of granulation tissue color by digital image analysis will be useful as an objective monitoring tool for granulation tissue quality or surrogate outcomes of pressure ulcer healing.

Relationship between morphological characteristics and etiology of pressure ulcers in intensive care unit patients.

PURPOSE: Pressure ulcer (PU) prevention is crucial for critically ill patients in the intensive care unit, but etiologic factors leading to their development have not yet been completely elucidated. This study explores the relationships among etiologic factors, interventional nursing care, and morphological characteristics of PUs in intensive care unit patients. DESIGN: We used a qualitative exploratory method to link morphological characteristics of specific PUs to etiologic factors. METHODS: Details of individual PUs were described by sketching the PU photograph and categorized to characterize the morphology of PUs. After identification of characteristics, the development process was evaluated by in-depth review of medical records. RESULTS: The morphological characteristics of 30 PUs were organized into 4 categories. This process revealed a type of PU not previously described, which we labeled "leaf-type." These PUs were located on the lower sacrum, rhombic-oval in shape, and characterized by purpura and PU wrinkles. Possible etiologic factors for the specific PUs were divided into 4 categories: (1) the occurrence of PU risk episodes, (2) failure of the peripheral circulation, (3) periods of critical immobility, and (4) position change techniques inducing skin deformation. CONCLUSION: PU can be categorized into 4 morphological types, including a new category of leaf-shaped PU. We found that frequently repeated position changes such as lateral tilt and repeated head elevation caused deformation of the sacral skin that may play a role in PU development.

Concurrent validation and reliability of digital image analysis of granulation tissue color for clinical pressure ulcers.

Granulation tissue color is one indicator for pressure ulcer (PU) assessment. However, it entails a subjective evaluation only, and quantitative methods have not been established. We developed color indicators from digital image analysis and investigated their concurrent validity and reliability for clinical PUs. A cross-sectional study was conducted on 47 patients with 55 full-thickness PUs. After color calibration, a wound photograph was converted into three images representing red color: erythema index (EI), modified erythema index with additional color calibration (granulation red index [GRI]), and , which represents the artificially created red-green axis of L(*) a(*) b(*) color space. The mean intensity of the granulation tissue region and the percentage of pixels exceeding the optimal cutoff intensity (% intensity) were calculated. Mean GRI (ρ=0.39, p=0.007) and (ρ=0.55, p<0.001), as well as their % intensity indicators, showed positive correlations with a(*) measured by tristimulus colorimeter, but erythema index did not. They were correlated with hydroxyproline concentration in wound fluid, healthy granulation tissue area, and blood hemoglobin level. Intra- and interrater reliability of the indicator calculation using both GRI and had an intraclass correlation coefficient >0.9. GRI and from digital image analysis can quantitatively evaluate granulation tissue color of clinical PUs.

Aging enhances maceration-induced ultrastructural alteration of the epidermis and impairment of skin barrier function.

BACKGROUND: Skin maceration is recognized as a risk factor for the development of certain skin lesions. In health care settings, incontinence-associated skin maceration is highly prevalent in the elderly. However, the effect of senescence on maceration has not been fully elucidated. OBJECTIVE: To reveal the enhancement of the maceration-induced ultrastructural alteration and barrier function of the epidermis by aging. METHODS: Skin maceration was reproduced by exposure to agarose gel in human and rat. The ultrastructural alterations in human and rat tissue were observed by transmission electron microscopy. The skin barrier function was evaluated by noninvasive methods in human, and by the transdermal penetration of small- and large-fluorescent molecules in rat. In order to reveal the effect of aging on the skin maceration, we compared these parameters between young and aged rats. RESULTS: In macerated skin, we observed expansion of the interstices of the stratum corneum, spinosum, and basale of the epidermis; disruption of the intercellular lipid structure in the stratum corneum; a decreased number of cell processes in the stratum spinosum and basale. The transdermal penetration test in the rat using two types of fluorescein indicated that maceration disrupted skin barrier function. Furthermore, senescence-enhanced ultrastructural and functional alterations were revealed in the rodent studies. CONCLUSION: This study demonstrates that aging enhances skin maceration. Considering that maceration is a risk factor for the skin damage, the development of technology to promote skin barrier recovery after maceration in the elderly is warranted.

Internet suicide in Japan: implications for child and adolescent mental health.

Internet suicide, also known as 'net suicide', is a phrase which has become one of the most notorious terms to the Japanese in recent times. 'Net suicide' refers to suicide pacts that are prearranged between strangers who meet over the internet. Japan has one of the highest suicide rates in the world with 32,325 people killing themselves in 2004. A worrying new trend of net suicide has emerged; as many as 60 people a year have died of this method and the numbers continue to rise. This phenomenon, however, does not limit itself to Japan; for instance in February 2005, the death of two strangers in London, believed to be Britain's first internet suicide, has given cause for concern that this could set a precedent for future such events in Europe and elsewhere. Although there is much research regarding suicide pacts, far less is known about such 'net suicide' pacts. Suicide is a multifaceted problem encompassing cultural, social, religious and economic dimensions, and suicide prevention is therefore best managed within a multidisciplinary framework. By examining this Japanese phenomenon, I conclude that individuals as well as society will have to play a complex, dynamic and interactive role in preventing future tragedies.