Effects of Liquid and Bar Soaps on the Skin of Brazilian Newborns: A Randomized Controlled Trial.

INTRODUCTION: Compared to adults, newborns' skin has a thinner epidermis and stratum corneum with decreased hydration levels, higher transepidermal water loss, and a pH variation between 5.5 and 7.5. These characteristics can predispose to the occurrence of dryness, infections, and dermatological conditions. Water and liquid soap with adequate formulation have shown to be beneficial and safe for newborns' skin. However, studies evaluating the effect of bar soap, products widely used in Brazil and Latin America, are unknown. Therefore, the objective of this study was to compare the effects of liquid and bar soaps on the term newborns' skin. METHODS: This randomized controlled, parallel, single-blind clinical trial was conducted at a public university hospital in São Paulo, Brazil. 100 healthy term newborns with no congenital anomalies, acute diseases, or dermatological conditions were randomized to use liquid soap (experimental group) or bar soap (control group). Skin pH, transepidermal water loss, stratum corneum hydration, sebum content, and skin condition were assessed before and after the first bath, at 48 h, 14 days, and 28 days after birth. These evaluations were performed on the forearm, abdomen, buttocks, and thigh. In addition, the mother's perception of soap use was also evaluated. RESULTS: Data of 100 newborns were analyzed by intention to treat. The rate of retention was 53%. Newborns exposed to the liquid soap presented significantly better skin acidification (p < 0.001) and significantly better stratum corneum hydration (p < 0.001) than the skin of newborns exposed to the bar soap, regardless of the area evaluated. There were no significant differences in transepidermal water loss, sebum content, dryness, erythema, or skin breakdown and the mother's perceptions of the use of the soaps. CONCLUSION: Newborns in the experimental group presented better skin acidification and stratum corneum hydration when compared to newborns in the control group.

Ultrastable and Responsive Foams Based on 10-Hydroxystearic Acid Soap for Spore Decontamination.

Currently, there is renewed interest in using fatty acid soaps as surfactants. Hydroxylated fatty acids are specific fatty acids with a hydroxyl group in the alkyl chain, giving rise to chirality and specific surfactant properties. The most famous hydroxylated fatty acid is 12-hydroxystearic acid (12-HSA), which is widely used in industry and comes from castor oil. A very similar and new hydroxylated fatty acid, 10-hydroxystearic acid (10-HSA), can be easily obtained from oleic acid by using microorganisms. Here, we studied for the first time the self-assembly and foaming properties of R-10-HSA soap in an aqueous solution. A multiscale approach was used by combining microscopy techniques, small-angle neutron scattering, wide-angle X-ray scattering, rheology experiments, and surface tension measurements as a function of temperature. The behavior of R-10-HSA was systematically compared with that of 12-HSA soap. Although multilamellar micron-sized tubes were observed for both R-10-HSA and 12-HSA, the structure of the self-assemblies at the nanoscale was different, which is probably due to the fact that the 12-HSA solutions were racemic mixtures, while the 10-HSA solutions were obtained from a pure R enantiomer. We also demonstrated that stable foams based on R-10-HSA soap can be used for cleaning applications, by studying spore removal on model surfaces in static conditions via foam imbibition.

An In Vitro Comparative Evaluation of Conventional and Novel Thymus vulgaris Derived Herbal Disinfectant Solutions against Pathogenic Biofilm on Maxillofacial Silicones and Its Impact on Color Stability.

AIM: This study aims to assess the antimicrobial efficacy and impact on color stability of Thymus (T.) vulgaris solution compared to conventional disinfectants on maxillofacial silicones. MATERIALS AND METHODS: Various solutions were evaluated, including T. vulgaris solutions at 5 and 10%, saline (control), chlorhexidine (4%), and soap water. The substrates were MDX4-4210 silicone elastomers, and the microorganisms tested were Candida (C.) albicans and Staphylococcus (S.) aureus. The viability of microorganisms was determined through an 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) reduction assay, and color stability was measured using a spectrophotometer with X-Rite Europe software. Statistical analysis was performed using the Kruskal-Wallis test, Mann-Whitney U post hoc test, and Wilcoxon Signed Rank test. RESULTS: Soap water demonstrated superior disinfectant action against both microorganisms, while T. vulgaris solutions at 5 and 10% exhibited comparable antimicrobial efficacy. Chlorhexidine and 10% T. vulgaris solution showed minimal color changes in the silicone material. In contrast, soap water and the 5% T. vulgaris solution resulted in clinically unacceptable color alterations. CONCLUSION: This study underscores the potential of T. vulgaris as an herbal disinfectant for combating microbial biofilms on maxillofacial silicones, particularly at concentrations of 5 and 10%. The importance of maintaining color stability is emphasized, with Chlorhexidine and the 10% T. vulgaris solution demonstrating effective preservation of esthetics. These findings suggest the viability of considering T. vulgaris as an alternative disinfectant in clinical settings for maxillofacial silicone prostheses. CLINICAL SIGNIFICANCE: Maxillofacial silicones are vital in restoring aesthetic features for individuals with facial trauma, congenital deformities, or post-surgical interventions. Yet, biofilm-related infections jeopardize their durability and visual integrity. Clinically, T. vulgaris signifies a potential advance in prosthodontic care, offering valuable insights for improving antimicrobial performance and aesthetic durability in maxillofacial prostheses. How to cite this article: Peter M, Kanathila H, Bembalagi M, et al. An In Vitro Comparative Evaluation of Conventional and Novel Thymus vulgaris Derived Herbal Disinfectant Solutions against Pathogenic Biofilm on Maxillofacial Silicones and Its Impact on Color Stability. J Contemp Dent Pract 2023;24(12):967-973.

Skin Cleansing without or with Compromise: Soaps and Syndets.

Products designed to cleanse the skin commonly do so through surfactant action, which leads to the lowering of the surface tension of the skin to facilitate the removal of dirt from its surface. Skin cleansers generally come in one of two types: soap-based and synthetic detergents, or syndets. While the latter can effectively maintain the native skin structure, function and integrity, the former tends to negatively affect the skin by causing barrier disruption, lipid dissolution and pH alteration. Despite this, soap is still often preferred, possibly due to the negative connotations around anything that is not perceived as 'natural'. It is, therefore, important that the science behind cleansers, especially those designed for the maintenance of healthy skin and the management of common skin conditions such as eczema, be understood by both formulators and end-users. Here, we carefully weigh the advantages and disadvantages of the different types of surfactant-the key ingredient(s) in skin cleansers-and provide insight into surfactants' physicochemical properties, biological activity and potential effects. Fine-tuning of the complex characteristics of surfactants can successfully lead to an 'optimal' skin cleanser that can simultaneously be milder in nature, highly effective and beneficial, and offer minimal skin interference and environmental impact.

Predicting Division Planes of Three-Dimensional Cells by Soap-Film Minimization.

One key aspect of cell division in multicellular organisms is the orientation of the division plane. Proper division plane establishment contributes to normal plant body organization. To determine the importance of cell geometry in division plane orientation, we designed a three-dimensional probabilistic mathematical model to directly test the century-old hypothesis that cell divisions mimic soap-film minima. According to this hypothesis, daughter cells have equal volume and the division plane occurs where the surface area is at a minimum. We compared predicted division planes to a plant microtubule array that marks the division site, the preprophase band (PPB). PPB location typically matched one of the predicted divisions. Predicted divisions offset from the PPB occurred when a neighboring cell wall or PPB was directly adjacent to the predicted division site to avoid creating a potentially structurally unfavorable four-way junction. By comparing divisions of differently shaped plant cells (maize [Zea mays] epidermal cells and developing ligule cells and Arabidopsis thaliana guard cells) and animal cells (Caenorhabditis elegans embryonic cells) to divisions simulated in silico, we demonstrate the generality of this model to accurately predict in vivo division. This powerful model can be used to separate the contribution of geometry from mechanical stresses or developmental regulation in predicting division plane orientation.

Melaleuca alternifolia essential oil soap: a potential alternative for hand hygiene.

This study aimed to compare the antimicrobial action of three soaps for hand hygiene (HH): 2.0% Tea Tree Oil (TTO); 0.5% triclosan; 2.0% chlorhexidine, and to explore the perception of healthcare professionals about TTO. Two-step study: a quantitative, to determine the logarithmic reduction of Escherichia coli K12 colony-forming units before and after HH of 15 volunteers and quali-quantitative, through interviews with 23 health professionals. All the three products demonstrated antimicrobial action (a log10 reduction factor of 4.18 for TTO, 4.31 for triclosan, 3.89 for chlorhexidine, and 3.17 for reference soap). Professionals remarked the pleasant aroma and non-dryness of skin when using soap containing TTO.

Effect of zinc pyrithione shampoo treatment on skin commensal Malassezia.

Malassezia restricta and Malassezia globosa are lipid dependent commensal yeasts associated with dandruff. Antifungal actives such as zinc pyrithione are commonly used in antidandruff shampoos, although their efficacy is not clearly demonstrated. In this study, we assessed the efficacy of antifungal treatments on scalp Malassezia via a combination of culturomic and genomic detection methods. Zinc pyrithione inhibited Malassezia growth at low minimum inhibitory concentrations (MICs). In a longitudinal pilot study, quantitative polymerase chain reaction (qPCR) analysis showed a decrease in M. restricta on the scalp after zinc pyrithione treatment. These findings validate the antifungal efficacy of zinc pyrithione as a dandruff treatment. LAY ABSTRACT: Malassezia yeasts are associated with dandruff and seborrheic dermatitis. Zinc pyrithione is effective against Malassezia growth in vitro and when tested on human skin as a shampoo. These findings will be useful for investigating the role of Malassezia in skin microbiome intervention studies.

Efficacy of soap and water based skin decontamination using in vivo animal models: a systematic review.

Water-only or soap and water solutions are considered a gold standard for skin decontamination. However, there is lack of conclusive data regarding their efficacy. The aim of this study was to summarize in vivo animal model data on skin decontamination using water-only, and/or soap and water. Covidence, Embase, MEDLINE, PubMed, Web of Science, and Google Scholar were searched to identify relevant articles using water-only or soap and water decontamination methods in in vivo animals. Data extraction was completed from studies, representing three animal models, and 11 contaminants. Results demonstrated water-only decontamination solutions led to complete decontamination in 3.1% (n = 16/524) protocols, incomplete decontamination in 90.6% (n = 475/524) of protocols, and mortality in 6.3% (n = 33/524) of protocols. Soap and water decontamination solutions resulted in complete decontamination in 6.9% (n = 8/116) protocols, incomplete decontamination in 92.2% (n = 107/116) of protocols, and mortality in 6.9% (n = 8/116) of protocols. Although water only, or soap and water is considered a gold standard for skin decontamination, most papers investigated found that water only, and soap and water provided incomplete decontamination. Due to the insufficient data, and limitations that hinder the applicability of available data, evidence indicates that more contemporary studies investigating skin decontamination are needed, and compared to other model species, including humans, when practical.

Efficacy of water-based skin decontamination of occupational chemicals using in vitro human skin models: a systematic review.

Percutaneous absorption of chemicals is a potential route of topical and systemic toxicity. Skin decontamination interrupts this process by removing contaminants from the skin surface. Decontamination using water-only or soap and water solutions is the current gold standard despite limited efficacy data. A summary of studies evaluating their efficacy in decontaminating occupational contaminants from in vitro human skin models is presented. Embase, MEDLINE, PubMed, Web of Science, and Google Scholar were searched for relevant articles and data extracted from 15 investigations that reported on 21 occupational contaminants, which were further classified as industrial chemicals, drugs, or pesticides. Water-only decontamination yielded no response in 4.3% (n = 6/140) and partial decontamination in 95.7% (n = 134/140) of skin samples. Soap and water decontamination yielded complete decontamination in 4.9% (n = 13/264) and partial decontamination in 95.1% (n = 251/264) of skin samples. Four studies (26.7%, n = 4/15) reported increased penetration rates or skin concentration of contaminants following decontamination, demonstrating a "wash-in" effect. Varying study methodologies hinder our ability to compare data and determine when water alone or soap and water are best used. International harmonized efficacy protocol might enhance our decontamination understanding and enable a more customized approach to decontamination clinical practice and research.

Systemic absorption of benzalkonium chloride after maximal use of a consumer antiseptic wash product.

An in vivo pharmacokinetic study was conducted using consumer antiseptic wash containing 0.13% benzalkonium chloride (BAC) to assess the effect of dermal absorption on long-term systemic exposure to BAC. The objective of the study was to determine blood levels of BAC under maximal use conditions. Subjects were enlisted to wash their hands 60 s with soap containing 0.13% BAC 30 times per day over an 8-9 h time period for 5 consecutive days. The test product with the highest absorption potential was selected based on market share and results from in vitro permeation testing. Blood plasma was collected from subjects on 32 occasions over the 6-day study period. Plasma samples were analyzed for the C12 and C14 homologs of BAC using LC-MS/MS with a lower limit of quantitation (LLOQ) of 106.9 and 32.6 ng/L, respectively. For the 32 subjects, C12 homolog was detected above the LLOQ in only four of 1,024 plasma samples at 117.8-191.7 ng/L, and C14 homolog was detected in only one sample at 59.5 ng/L. Consequently, systemic exposure to BAC in antimicrobial soap is very low and below the level of concern identified by the U.S. Food and Drug Administration (500 ng/L) even under maximal use conditions.

Hygiene and emollient interventions for maintaining skin integrity in older people in hospital and residential care settings.

BACKGROUND: Ageing has a degenerative effect on the skin, leaving it more vulnerable to damage. Hygiene and emollient interventions may help maintain skin integrity in older people in hospital and residential care settings; however, at present, most care is based on "tried and tested" practice, rather than on evidence. OBJECTIVES: To assess the effects of hygiene and emollient interventions for maintaining skin integrity in older people in hospital and residential care settings. SEARCH METHODS: We searched the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL, up to January 2019. We also searched five trials registers. SELECTION CRITERIA: Randomised controlled trials comparing hygiene and emollient interventions versus placebo, no intervention, or standard practices for older people aged ≥ 60 years in hospital or residential care settings. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures as expected by Cochrane. Primary outcomes were frequency of skin damage, for example, complete loss of integrity (tears or ulceration) or partial loss of integrity (fissuring), and side effects. Secondary outcomes included transepidermal water loss (TEWL), stratum corneum hydration (SCH), erythema, and clinical scores of dryness or itch. We used GRADE to assess the quality of evidence. MAIN RESULTS: We included six trials involving 1598 residential care home residents; no included trial had a hospital setting. Most participants had a mean age of 80+ years; when specified, more women were recruited than men. Two studies included only people with diagnosed dry skin. Studies were conducted in Asia, Australasia, Europe, and North America. A range of hygiene and emollient interventions were assessed: a moisturising soap bar; combinations of water soak, oil soak, and lotion; regular application of a commercially available moisturiser; use of two different standardised skin care regimens comprising a body wash and leave-on body lotion; bed bath with "wash gloves" containing numerous ingredients; and application of a hot towel after usual care bed bath. In five studies, treatment duration ranged from five days to six months; only one study had post-treatment follow-up (one to eight days from end of treatment). Outcomes in the hot towel study were measured 15 minutes after the skin was wiped with a dry towel. Three studies each had high risk of attrition, detection, and performance bias. Only one trial (n = 984) assessed frequency of skin damage via average monthly incidence of skin tears during six months of treatment. The emollient group (usual care plus twice-daily application of moisturiser) had 5.76 tears per month per 1000 occupied bed-days compared with 10.57 tears in the usual care only group (ad hoc or no standardised skin-moisturising regimen) (P = 0.004), but this is based on very low-quality evidence, so we are uncertain of this result. Only one trial (n = 133) reported measuring side effects. At 56 ± 4 days from baseline, there were three undesirable effects (itch (mild), redness (mild/moderate), and irritation (severe)) in intervention group 1 (regimen consisting of a moisturising body wash and a moisturising leave-on lotion) and one event (mild skin dryness) in intervention group 2 (regimen consisting of body wash and a water-in-oil emulsion containing emollients and 4% urea). In both groups, the body wash was used daily and the emollient twice daily for eight weeks. There were zero adverse events in the usual care group. This result is based on very low-quality evidence. This same study also measured TEWL at 56 ± 4 days in the mid-volar forearm (n = 106) and the lower leg (n = 105). Compared to usual care, there may be no difference in TEWL between intervention groups, but evidence quality is low. One study, which compared application of a hot towel for 10 seconds after a usual care bed bath versus usual care bed bath only, also measured TEWL at 15 minutes after the skin was wiped with a dry towel for one second. The mean TEWL was 8.6 g/m²/h (standard deviation (SD) 3.2) in the hot towel group compared with 8.9 g/m²/h (SD 4.1) in the usual care group (low-quality evidence; n = 42), showing there may be little or no difference between groups. A lower score is more favourable. Three studies (266 participants) measured SCH, but all evidence is of very low quality; we did not combine these studies due to differences in treatments (different skin care regimens for eight weeks; wash gloves for 12 weeks; and single application of hot towel to the skin) and differences in outcome reporting. All three studies showed no clear difference in SCH at follow-up (ranging from 15 minutes after the intervention to 12 weeks from baseline), when compared with usual care. A clinical score of dryness was measured by three studies (including 245 participants); pooling was not appropriate. The treatment groups (different skin care regimens for eight weeks; a moisturising soap bar used for five days; and combinations of water soak, oil soak, and lotion for 12 days) may reduce dryness compared to standard care or no intervention (results measured at 5, 8, and 56 ± 4 days after treatment was initiated). However, the quality of evidence for this outcome is low. Outcomes of erythema and clinical score of itch were not assessed in any included studies. AUTHORS' CONCLUSIONS: Current evidence about the effects of hygiene and emollients in maintaining skin integrity in older people in residential and hospital settings is inadequate. We cannot draw conclusions regarding frequency of skin damage or side effects due to very low-quality evidence. Low-quality evidence suggests that in residential care settings for older people, certain types of hygiene and emollient interventions (two different standardised skin care regimens; moisturising soap bar; combinations of water soak, oil soak, and lotion) may be more effective in terms of clinical score of dryness when compared with no intervention or standard care. Studies were small and generally lacked methodological rigour, and information on effect sizes and precision was absent. More clinical trials are needed to guide practice; future studies should use a standard approach to measuring treatment effects and should include patient-reported outcomes, such as comfort and acceptability.

Electrode modified with graphene quantum dots supported in chitosan for electrochemical methods and non-linear deconvolution of spectra for spectrometric methods: approaches for simultaneous determination of triclosan and methylparaben.

Two analytical methods were developed using electrochemical and spectrometric techniques for the simultaneous determination of endocrine disruptors triclosan and methylparaben in the monitoring of personal care products. For the electroanalytical analyses, a sensitive electrode based on graphene quantum dots supported in chitosan was employed. Under optimized conditions and a working potential of typically + 0.60 V for triclosan and + 0.81 V (vs. Ag/AgCl) for methylparaben, the calibration plots obtained by differential pulse voltammetry were linear in the range 0.10 to 10.0 µmol L-1. The detection limits were 0.03 and 0.04 µmol L-1 for triclosan and methylparaben, respectively. For the spectrometric method, UV/VIS spectrometry was used with a mathematical processing of non-linear deconvolution. This processing was used to solve the problem of overlapping absorption bands of triclosan (282 nm) and methylparaben (257 nm), which enabled simultaneous determination. The calibration plots by UV/VIS spectrometry were linear in the range 1.0 to 14.0 µmol L-1 with detection limits of 0.42 and 0.37 µmol L-1, respectively, for triclosan and methylparaben. Similar results obtained from the calibration plots of individual analytes suggest that the methods can be applied for individual or simultaneous determination of these species. Both methods were employed in the analysis of five samples of personal care products: toothpaste, antiseptic soap, antiseptic deodorant, shampoo, and a bath kit (soap and shampoo). The statistical tests indicated that there were no significant differences regarding the accuracy and precision of the data provided by the two methods described herein. Graphical abstract Schematic representation for simultaneous determination of triclosan and methylparaben: electrochemical method employing an electrode modified with graphene quantum dots supported in chitosan and spectrometric method applying a non-linear deconvolution of spectrum.

Study of the cytotoxic and irritant effects of skin cleansing soaps.

BACKGROUND: The use of soap for skin cleansing is common among the population. However, it is possible that it causes damage to skin cells and disrupts the skin barrier. OBJECTIVE: To determine the cytotoxic effect of soaps on in vitro-cultured keratinocytes and to correlate it with clinical irritation. METHOD: A survey was conducted to find out the most widely used commercial soaps and their number. Subsequently, their cytotoxicity was evaluated in human keratinocyte cultures using the resazurin assay. The soaps with the highest and lowest cytotoxicity were applied to the skin of healthy volunteers to assess their effect on the skin barrier using colorimetry and transepidermal water loss (TEWL) assays. RESULTS: Of the analyzed soaps, 37 % were shown to be toxic to keratinocytes in vitro. The soap with the highest toxicity induced the highest rate of erythema and TEWL, in comparison with the least toxic soap and the vehicle used as the control solution. CONCLUSION: Soaps marketed for skin cleansing can contain chemical ingredients that damage human keratinocytes and cause skin barrier subclinical irritation. Their use can worsen preexisting dermatoses, generate xerotic or irritant contact dermatitis, and cause atrophy and dermatoporosis.

INTRODUCCIÓN: El jabón para el aseo cutáneo es de empleo común entre la población, sin embargo, es posible que cause daño a las células de la piel y modifique la barrera cutánea. OBJETIVO: Determinar el efecto citotóxico de los jabones en queratinocitos cultivados in vitro y correlacionarlo con la irritación clínica. MÉTODO: Se realizó una encuesta para conocer los jabones comerciales más utilizados y su cantidad; posteriormente, se evaluó su citotoxicidad en cultivos de queratinocitos humanos mediante el método de resazurina. Los jabones con mayor y menor citotoxicidad se aplicaron en piel de voluntarios sanos para evaluar su efecto en la barrera cutánea mediante ensayos de colorimetría y pérdida transepidérmica de agua. RESULTADOS: De los jabones analizados, 37 % demostró ser tóxico para los queratinocitos in vitro. El jabón con mayor toxicidad indujo el mayor índice de eritema y pérdida transepidérmica de agua, en comparación con el jabón menos tóxico y el vehículo empleado como solución control. CONCLUSIÓN: Los jabones comercializados para el aseo cutáneo pueden incluir ingredientes químicos que dañan los queratinocitos humanos y causan irritación subclínica de la barrera cutánea. Su utilización puede agravar dermatosis preexistentes, generar dermatitis xerósica o de contacto irritativa y causar atrofia y dermatoporosis.

Inhibitory effects of Azadirachta indica secondary metabolites formulated cosmetics on some infectious pathogens and oxidative stress radicals.

BACKGROUND: Infectious diseases, particularly those due to multi-drug resistant bacterial strains are almost impossible to cure globally. In this study we investigated the inhibitory effects of Azadirachta indica A. Juss secondary metabolites (AISM) formulated soap and cream for management of infectious and oxidative stress-related diseases (OSD). METHODS: The antibacterial, radical scavenging and cytotoxic effects of the neem cosmetics were examined by serial dilution, spectrophotometric and hemolytic techniques respectively, while the AISM in the essential oils (EOs) were elucidated by Gas chromatography-mass spectrometry (GC-MS) and retention index. RESULTS: The neem cosmetics without AISM exhibited bacteriostatic effects against five reference bacterial strains (Staphylococcus aureus, Listeria ivanovii, Enterobacter cloacae, Mycobacterium smegmatis, and Streptococcus uberis) and two confirmed multi-drug resistant bacterial strains (Vibrio paraheamolyticues, Escherichia coli 180) at 0.80 mg/mL. Conversely, at less than 0.50 mg/mL the neem soap produced with AISM demonstrated bactericidal effects against most of these test pathogens linked to infectious diseases. The neem soap containing AISMs displayed noteworthy effects in scavenging radicals associated with OSD at < 1.76 mg/mL. The cosmetics were not toxic to human red blood cells below 0.70 mg/ mL. To our known, the AISM predominantly caryophyllene (30.02%), phytol (14.12%), elemene (13.40%) and linoleic acid (10.5%) exceptional inhibitory effects in neem cosmetics are reported here for the first time. CONCLUSION: The study indicates that apart from traditional uses of A. indica, the EO contained potent bioactive AISM and feasible as an antimicrobial agent, an alternative to synthetic antioxidant, likewise considered novel in the pharmaceutical, cosmetics industries and as food preservatives.

Effect of Chemical Disinfectants on the Color Stability of Maxillofacial Silicones: An In Vitro Study.

PURPOSE: To evaluate the effect of chemical disinfection on the color stability of room temperature vulcanizing (RTV) maxillofacial silicone elastomer with and without pigment addition. MATERIALS AND METHODS: Sixty specimens were obtained from a RTV maxillofacial silicone. The specimens were randomly divided into 6 groups according to pigments and disinfectant to be used (n = 10). NP-DW-nonpigmented silicone specimens to be immersed in distilled water (control). NP-S- nonpigmented silicone specimens to be rubbed with an anti-bacterial soap. NP-CHX-nonpigmented silicone specimens to be immersed in chlorhexidine gluconate solution (2%). P-DW-pigmented silicone specimens to be immersed in distilled water (control). P-S-pigmented silicone specimens to be rubbed with antibacterial soap. P-CHX-pigmented silicone specimens to be immersed in chlorhexidine gluconate solution (2%). Disinfection was conducted 6 times a day for 60 days simulating 1 year of usage. Color was evaluated after 60 days (disinfection period) using a reflectance spectrophotometer. Color alterations were calculated by the CIE L∗ a∗ b∗ system. Data were analyzed by t-test, one-way ANOVA, and Tukey test (α = 0.05). RESULTS: NP-S and P-S exhibited the highest color alterations, whereas NP-DW and P-DW the lowest color alterations. CONCLUSION: Disinfection procedures affect the color stability of maxillofacial silicone. Chlorhexidine gluconate solution (2%) can be effectively used as a chemical disinfectant for maxillofacial prostheses. Antibacterial soap produced clinically unacceptable color changes in the silicone, hence is not advisable as a disinfectant.

The Effects of Cold Saponification on the Unsaponified Fatty Acid Composition and Sensory Perception of Commercial Natural Herbal Soaps.

Saponification is the process in which triglycerides are combined with a strong base to form fatty acid metal salts during the soap-making process. The distribution of unsaturated and saturated fatty acid determines the hardness, aroma, cleansing, lather, and moisturizing abilities of soaps. Plant extracts, such as rosemary, vegetable, and essential oils are frequently added to soaps to enhance quality and sensory appeal. Three natural soaps were formulated using cold saponification to produce a base or control bar (BB), hibiscus rosehip bar (H), and a forest grove bar (FG). Rosemary extract (R) or essential oil (A) blends were added as additives to each formulation prior to curing to evaluate the effects of natural plant additives on the lipid composition and sensory characteristics of these natural herbal soaps. A total of seven natural soaps, three without additives (BB, H, FG) and four with additives (BBR, HA, FGR, FGA), were manufactured and studied. The majority (86⁻99%) of the polyunsaturated fatty acids (5.0⁻7.0 µg/mg) remained unsaponified in the manufactured natural soaps regardless of feedstock used. Principal component analysis (PCA) analyses showed the unsaponifiable fatty acids were different in the hibiscus bar compared to the other bars. There was a very strong correlation between the content of unsaponified C18:3n3 and C18:1n9 in all natural soaps. These results indicate that unsaponified fatty acids are important contributors to the quality and overall sensory perception and preference of natural herbal soaps following manufacturing by cold saponification.

Evaluation of combinations of putative anti-biofilm agents and antibiotics to eradicate biofilms of Staphylococcus aureus and Pseudomonas aeruginosa.

Objectives: To evaluate potential anti-biofilm agents for their ability to enhance the activity of antibiotics for local treatment of localized biofilm infections. Methods: Staphylococcus aureus and Pseudomonas aeruginosa in vitro biofilm models were developed. The putative antibiotic enhancers N-acetylcysteine, acetylsalicylic acid, sodium salicylate, recombinant human deoxyribonuclease I, dispersin B, hydrogen peroxide and Johnson's Baby Shampoo (JBS) were tested for their anti-biofilm activity alone and their ability to enhance the activity of antibiotics for 7 or 14 days, against 5 day old biofilms. The antibiotic enhancers were paired with rifampicin and clindamycin against S. aureus and gentamicin and ciprofloxacin against P. aeruginosa. Isolates from biofilms that were not eradicated were tested for antibiotic resistance. Results: Antibiotic levels 10× MIC and 100× MIC significantly reduced biofilm, but did not consistently eradicate it. Antibiotics at 100× MIC with 10% JBS for 14 days was the only treatment to eradicate both staphylococcal and pseudomonal biofilms. Recombinant human deoxyribonuclease I significantly reduced staphylococcal biofilm. Emergence of resistance of surviving isolates was minimal and was often associated with the small colony variant phenotype. Conclusions: JBS enhanced the activity of antibiotics and several other promising anti-biofilm agents were identified. Antibiotics with 10% JBS eradicated biofilms produced by both organisms. Such combinations might be useful in local treatment of localized biofilm infections.

Metabolic and molecular responses to calcium soap of fish oil fed to ewes during peripartal period.

It has been shown that n-3 long chain fatty acids (n-3 LCFA) are involved in energy/lipid metabolisms, reproductive parameters, and molecular regulations leading to maintained homeostasis. We hypothesized that supplementation of peripartal diets with fish oil (FO), as a source of n-3 LCFA, could improve energy balance and modulate metabolic pressure in a sheep model. Prepartum ewes (n = 24) were fed control (CON) or calcium soap of fish oil (FO) supplemented-diet from four weeks before until three weeks after parturation. Feed intake, body weight (BW) change, plasma metabolites, colostrums/milk composition, and fatty acids profile of milk along with the expression of core microRNAs in glucose and lipid metabolism were evaluated. Prepartal feed intake decreased in FO group (1674 ± 33.26 vs. 1812 ± 35.56) though post-partal intake was similar. Differences in BW were not also significant (55.47 ± 2.07 in CON vs. 53.69 ± 1.94 in FO). No differences were observed in plasma metabolites except for cholesterol that was lower in FO group (56.25 ± 0.71 vs. 53.09 ± 0.61). Milk fat percentage was reduced (8.82 ± 0.49 vs. 7.03 ± 0.45) while the percentage of milk total n-3 LCFA increased in FO group. In accordance, the relative transcript abundance of miR-101 (0.215 ± 0.08) and miR-103 (0.37 ± 0.15) decreased by FO supplementation. Results showed that FO supplementation during peripartal period decreased milk fat, feed intake, plasma cholesterol, milk n-6:n-3 ratio and the expression of miR-101. Although the trend indicated that FO could alter lipid metabolism during transition period, further studies are needed to fully address its effect on energy balance and homeorhetic processes.

Integrating habits and practices data for soaps, cosmetics and air care products into an existing aggregate exposure model.

In order to accurately assess aggregate exposure to a fragrance material in consumers, data are needed on consumer habits and practices, as well as the concentration of the fragrance material in those products. The present study describes the development of Phase 2 Creme RIFM model by expanding the previously developed Phase 1 model to include an additional six product types. Using subject-matching algorithms, the subjects in the Phase 1 Creme RIFM database were paired with subjects in the SUPERB and BodyCare surveys based on age and gender. Consumption of the additional products was simulated to create a seven day diary allowing full data integration in a consistent format. The inhalation route was also included for air care and other products where a fraction of product used is inhaled, derived from the RIFM 2-box model. The expansion of the Phase 1 Creme RIFM model has resulted in a more extensive and refined model, which covers a broader range of product categories and now, includes all relevant routes of exposure. An evaluation of the performance of the model has been carried out in an accompanying publication to this one.

Boundary singularities produced by the motion of soap films.

Recent work has shown that a Möbius strip soap film rendered unstable by deforming its frame changes topology to that of a disk through a "neck-pinching" boundary singularity. This behavior is unlike that of the catenoid, which transitions to two disks through a bulk singularity. It is not yet understood whether the type of singularity is generally a consequence of the surface topology, nor how this dependence could arise from an equation of motion for the surface. To address these questions we investigate experimentally, computationally, and theoretically the route to singularities of soap films with different topologies, including a family of punctured Klein bottles. We show that the location of singularities (bulk or boundary) may depend on the path of the boundary deformation. In the unstable regime the driving force for soap-film motion is the mean curvature. Thus, the narrowest part of the neck, associated with the shortest nontrivial closed geodesic of the surface, has the highest curvature and is the fastest moving. Just before onset of the instability there exists on the stable surface the shortest closed geodesic, which is the initial condition for evolution of the neck's geodesics, all of which have the same topological relationship to the frame. We make the plausible conjectures that if the initial geodesic is linked to the boundary, then the singularity will occur at the boundary, whereas if the two are unlinked initially, then the singularity will occur in the bulk. Numerical study of mean curvature flows and experiments support these conjectures.