Impact of water exposure on skin barrier permeability and ultrastructure.

BACKGROUND: Skin occlusion caused by the use of diapers or sanitary napkins often results in irritant contact dermatitis. Furthermore, prolonged occlusion and exposure to body fluids are known to increase skin hydration and permeability, thus leading to irritant contact dermatitis. OBJECTIVE: To investigate the effects of water exposure on the skin and its barrier functions, in order to obtain more insights into the mechanisms of irritant contact dermatitis. METHODS: Water patches were applied to the volar forearm skin of 10 human subjects for 3 hours. Permeability of the stratum corneum (SC) was examined with methyl nicotinate (MN). Alterations in the hydration and ultrastructure of the SC were measured with Raman spectroscopy and multiphoton microscopy, respectively. RESULTS: Water profiles found with Raman spectroscopy showed notable increases in water content throughout the SC and skin surface. Multiphoton microscopy showed morphological changes in the intercellular space of the SC. Emerged pools seemed to contribute to increased MN absorption. CONCLUSION: Excessive skin hydration leading to changes in the SC ultrastructure might result in increased skin permeability to skin irritants and allergens.

Relationship between swallowing functions and health-related quality of life among community-dwelling dependent older individuals.

AIM: This study analyzed the association between swallowing function levels and health-related quality of life (QOL) among community-dwelling dependent older persons in Japan. METHODS: A cross-sectional survey of a purposive sample of community-dwelling dependent older individuals in Japan was conducted. Two swallowing functions (tongue pressure and lip-closure force), the risk of dysphagia, and health-related QOL (SF-8) were surveyed. RESULTS: There were 86 (38.2%) men and 139 (61.8%) women, with a mean age of 81.6 ± 7.4 years. The activities of daily living-20 evaluation yielded a total score of 46.39 ± 10.18. The elderly participants had decreased swallowing functions. The risk-of-dysphagia score demonstrated a significant negative correlation with respect to the SF-8 subcategory scores. Moreover, the multiple regression analyses indicated that three variables exhibited significant negative differences: general health perceptions, mental health (SF-8 subarea), and activities of daily living. CONCLUSION: An increasing risk of dysphagia can lead to a deterioration in the health-related QOL among community-dwelling dependent older individuals. This implies that homecare interventions that address the deterioration of swallowing and the risk of dysphagia could be in high demand in the future.

[The association between health-related quality of life and voice as evaluated by an acoustic analysis in elderly Japanese nursing home residents].

PURPOSE: We carried out a cross-sectional study investigating the association between health-related quality of life (HRQOL) and voice, as evaluated by an acoustic analysis, in elderly residents of a nursing home. METHODS: The HRQOL of 61 elderly nursing home residents (mean age: 82.1±8.3 years) was assessed via the SF-8 Health Survey questionnaire, Japanese version (SF-8). The subjects' voices were recorded and analyzed by a voice assessment software program, which calculated the pitch period perturbation quotient (PPQ), amplitude perturbation quotient (APQ), and noise-to-harmonic ratio (NHR). RESULTS: Subjects who scored under the 25th percentile on general health (GH), vitality (VT), or physical summary (PCS) in the SF-8 showed significantly higher PPQ, APQ, and NHR scores in comparison to their counterparts (p<0.05). After adjustment for age, lower GH scores were found to be associated with higher PPQ, APQ, and NHR scores; lower VT scores were associated with higher APQ and NHR scores; and lower PCS scores were associated with higher APQ and NHR scores (p<0.05). CONCLUSION: The results of the acoustic analysis indicated that voice was associated with HRQOL in the elderly nursing home residents of the present study. Among the acoustic parameters that were analyzed, PPQ, APQ, and NHR may be an influential factor that can be used to assess HRQOL, independently of the effects of age, in elderly individuals.

[Relationship between the nutritional status and the oral function among community-dwelling dependent elderly persons].

AIM: We herein examined the relationship between the nutritional status and the oral function among community-dwelling dependent elderly persons. METHODS: The subjects included 218 community-dwelling dependent elderly persons. The data were collected via questionnaires, including information regarding age, sex, the level of care required, nutritional status and swallowing function. We used the Mini Nutritional Assessment-Short Form (MNA-SF) to measure the nutritional status and the Dysphagia Risk Assessment for the Community-dwelling Elderly (DRACE) to evaluate the swallowing function. The tongue pressure and the labial closure force were measured using a tongue pressure measurement system (JMS Co. Ltd., Hiroshima, Japan) and the Lip de Cum (Cosmo-Instruments Co, Ltd, Tokyo, Japan). RESULTS: The mean MNA-SF score was 10.07±2.58. The mean DRACE score was 4.39±3.80. The mean tongue pressure was 23.89±10.61 kPa. The mean labial closure force was 10.17±6.04 N. The results of bivariate regression analyses showed that there was a poor correlation between the MNA-SF and the DRACE, tongue pressure and labial closure force. Furthermore, the multiple regression analysis with the MNA-SF as the dependent variable revealed a correlation between the DRACE and labial closure force (p<0.01, R(2)=0.02). CONCLUSIONS: Our results suggest that the nutritional status is significantly related to the swallowing function and labial closure force among community-dwelling dependent elderly persons.

[Relationship between the swallowing function and the health-related QOL among community-dwelling dependent elderly persons].

AIM: We examined the relationship between the swallowing function and the health-related QOL (quality of life) among community-dwelling dependent elderly persons. METHODS: The subjects included 191 community-dwelling dependent elderly persons. Data were collected via questionnaires, including information regarding age, gender, the level of care required, post-cerebrovascular disease, the health-related QOL and the swallowing function. We used the SF-8 to measure the health-related QOL and the DRACE (Dysphagia Risk Assessment for the Community-dwelling Elderly) to evaluate the swallowing function. RESULTS: The average DRACE score was 4.29±3.81. In addition, the swallowing risk was found to be related to the SF (social functioning) and MH (mental health) subscales of the SF-8. CONCLUSIONS: Our results suggest that the swallowing function is significantly related to the health-related QOL among community-dwelling dependent elderly persons.

[Relationship between comprehensive quality of life and factors related to chewing and swallowing function among community-dwelling elderly individuals].

AIM: The purpose of the present study was to examine the relationship between comprehensive quality of life (QOL) and some factors regarding chewing and swallowing function among community-dwelling elderly individuals. METHODS: The subjects were 675 independent elderly persons residing in the northern area of Miyazaki Prefecture, and we obtained the self-administered questionnaires from 545 elderly people. We used "active scale for the elderly (ASE)" and "dysphagia risk assessment for the community-dwelling elderly (DRACE)" to evaluate their comprehensive QOL and function of chewing and swallowing, respectively. Furthermore, we examined some factors such as age, gender, subjective satisfaction with diet and verbal communication. RESULTS: The score of ASE showed a significant decline with age (p<0.01) while the DRACE score increased significantly with age (p<0.01). Pearson's correlation coefficients revealed that the ASE score was significantly related to all of the factors regarding regulation of food intake. Partial correlation coefficients adjusted for age also revealed the same tendency. From the multiple regression analysis, subjective satisfaction with verbal communication, DRACE score, age and appetite were extracted as factors influencing ASE score (adjusted R(2)=0.43, p<0.01). CONCLUSION: Among independent elderly persons residing in the community, the comprehensive QOL was significantly related to factors such as subjective satisfaction with verbal communication, dysphagia risk, age, and appetite.

The role of neprilysin in regulating the hair cycle.

In most mammals, each hair follicle undergoes a cyclic process of growing, regressing and resting phases (anagen, catagen, telogen, respectively) called the hair cycle. Various biological factors have been reported to regulate or to synchronize with the hair cycle. Some factors involved in the extracellular matrix, which is a major component of skin tissue, are also thought to regulate the hair cycle. We have focused on an enzyme that degrades elastin, which is associated with skin elasticity. Since our previous study identified skin fibroblast elastase as neprilysin (NEP), we examined the fluctuation of NEP enzyme activity and its expression during the synchronized hair cycle of rats. NEP activity in the skin was elevated at early anagen, and decreased during catagen to telogen. The expression of NEP mRNA and protein levels was modulated similarly. Immunostaining showed changes in NEP localization throughout the hair cycle, from the follicular epithelium during early anagen to the dermal papilla during catagen. To determine whether NEP plays an important role in regulating the hair cycle, we used a specific inhibitor of NEP (NPLT). NPLT was applied topically daily to the dorsal skin of C3H mice, which had been depilated in advance. Mice treated with NPLT had significantly suppressed hair growth. These data suggest that NEP plays an important role in regulating the hair cycle by its increased expression and activity in the follicular epithelium during early anagen.

Neprilysin is identical to skin fibroblast elastase: its role in skin aging and UV responses.

Although human skin fibroblast (HSF) elastase has been characterized as a membrane-bound metalloproteinase, little is known about its structure, amino acid sequence, and encoding gene. As there are similarities in the molecular weights and inhibitory profiles of HSF elastase and neprilysin (neutral endopeptidase 24.11 (NEP)), in this study we tested the hypothesis that they are identical using immunoprecipitation and transfection methods. An immunoprecipitation study demonstrated that HSF elastase activity co-immunoprecipitated with anti-NEP in lysates of cultured HSF. Transfection of an NEP cDNA expression vector into COS-1 cells elicited the expression of HSF elastase and NEP activities in the transfected cells. These findings strongly suggest that HSF elastase is identical to NEP, which functions mainly in neuron-associated cells to degrade neuropeptides. Analysis of the expression pattern of NEP revealed that its expression was remarkably up-regulated at the gene, protein, and enzymatic activity levels during the replicative senescence of cultured HSF. Further, the activity of NEP was markedly enhanced in a pattern similar to elastase activity during the intrinsic aging of mouse skin, in UVA-exposed HSF as well as in HSF treated with conditioned medium from UVB-exposed human keratinocytes. Analysis of the cytokine profile for the stimulation of NEP and HSF elastase activities in HSF demonstrated that among the 11 cytokines tested, IL-1α, IL-1ß, IL-6, IL-8, and GM-CSF had the potential to significantly stimulate both activities similarly, again supporting the identity of HSF elastase and NEP.

Coordination of divalent metal cation to amide group to form adduct ion in FAB mass spectrometry: implication of Zn2+ in enzymatic hydrolysis of amide bond.

The structures of complexes between amides and metal ions were examined by FAB mass spectrometry and collision-induced dissociation (CID). Zn2+ was coordinated by the amide carbonyl oxygen atom of N-tetradecylacetamide (1). In contrast, Ca2+ and Mg2+ were coordinated by the amide group of 1 in both the keto and enol forms. The catalytic role of Zn2+ at the active site of the hydrolases might partly be explained by the effective attack of Zn2+ on carbonyl oxygen atom of the scissile amide group.

Conversion of Ca2+ salt of an organic compound to its Li+ salt to simplify the fast atom bombardment mass spectrum.

The FAB mass spectrum of the Ca(2+) salt of RK-682 (1, MW 368), a potent protein tyrosine phosphatase inhibitor, shows a complex pattern due to Ca(2+) adduct ions with multimers of 1 and their decomposition ions. Addition of LiCl greatly simplified the FAB mass spectrum, providing a prominent Li(+) adduct ion of 1 at m/z 381 [M+2Li-H](+). The addition of LiCl also greatly simplified the FAB mass spectrum of calcium pantothenate. This approach may be generally useful for molecular weight determination of multivalent metal salts of organic compounds, or organic compounds that can form Li salts, by FAB mass spectrometry.

Involvement of protein kinase C activation in L-leucine-induced stimulation of protein synthesis in l6 myotubes.

Effects of leucine and related compounds on protein synthesis were studied in L6 myotubes. The incorporation of [(3)H]tyrosine into cellular protein was measured as an index of protein synthesis. In leucine-depleted L6 myotubes, leucine and its keto acid, alpha-ketoisocaproic acid (KIC), stimulated protein synthesis, while D-leucine did not. Mepacrine, an inhibitor of both phospholipases A(2) and C, canceled stimulatory actions of L-leucine and KIC on protein synthesis. Neither indomethacin, an inhibitor of cyclooxygenase, nor caffeic acid, an inhibitor of lipoxygenase, diminished their stimulatory actions, suggesting no involvement of arachidonic acid metabolism. Conversely, 1-O-hexadecyl-2-O-methylglycerol, an inhibitor of proteinkinase C, significantly canceled the stimulatory actions of L-leucine and KIC on protein synthesis, suggesting an involvement of phosphatidylinositol degradation and activation of protein kinase C. L-Leucine caused a rapid activation of protein kinase C in both cytosol and membrane fractions of the cells. These results strongly suggest that both L-leucine and KIC stimulate protein synthesis in L6 myotubes through activation of phospholipase C and protein kinase C.

Coordination of sodium cation to an oxygen function and olefinic double bond to form molecular adduct ion in fast atom bombardment mass spectrometry.

Steroidal allylic alcohols formed Na+ adduct ion peaks [M+Na]+ by the addition of NaCl in FAB mass spectrometry. A comparison of the intensities of the adduct ion peaks of allylic alcohols with those of the corresponding saturated alcohols and olefin suggested that the olefinic double bond and the proximal hydroxyl group had coordinated to Na+. The adduct ion was stable and did not undergo dehydroxylation. We suggest that the Na+ adduction will be useful for the molecular weight determination of allylic alcohols which are susceptible to dehydroxylation under FAB mass spectrometric conditions. Na+ adduct ions of alpha,beta-unsaturated carbonyl compounds were also investigated.