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Introduction Skin provides critical barrier properties that enable terrestrial life. Myriad research has focused on the "water barrier" to transepidermal water loss (TEWL) despite there being a multitude of skin barrier properties. We asked what other barrier properties may have been overlooked and compiled data demonstrating the "electrolyte barrier" to be of potential clinical relevance. Methods A literature search was conducted through PubMed, Embase, Google Scholar, and Web of Science databases for the following keywords: "transepidermal" or "epidermal" or "cutaneous" or "skin" or "percutaneous" and "ion" or "sodium" or "chloride" or "potassium" or "electrolyte" and "flux" or "egression." Textbooks at the University of California, San Francisco were also hand reviewed. Experimental studies quantifying in vivo or ex vivo percutaneous egression of ions in response to human skin barrier perturbation were included. Results Experimental damage to skin, mostly by tape-stripping, frequently induced increased ion flux rates through the epidermis, in addition to increases in TEWL values. Interestingly, barrier perturbation did not always result in a concomitant rise in TEWL and transepidermal ion flux rates, such as in delipidization, indicating a distinction between the two barriers. Conclusion Quantifying the percutaneous egression of ions in response to physical or chemical alterations may offer additional data that are not to be captured with TEWL studies exclusively. Continued efforts should be made to: (1) advance this technique as a method of assessing skin status and (2) enhance our understanding of other barriers and mechanisms.

Background: Almonds have long been studied as a rich source of fatty acids, phytochemical polyphenols and antioxidants such as vitamin E. A recent study compared almond supplementations to a calorie-matched intervention for 16 weeks, yielding statistically significant improvement in wrinkle severity in postmenopausal women with Fitzpatrick skin types I and II that received almonds. This study furthers that assessment with a larger population and duration of 24 weeks to assess the influence of almond consumption on wrinkle severity, skin pigmentation and other skin biophysical profiles. Objective: To investigate the effects of almond consumption on photoaging such as wrinkles and pigment intensity as well as facial biophysical parameters such as sebum production, skin hydration and water loss. Design and interventions: A prospective, randomized controlled study assessed postmenopausal women with Fitzpatrick skin types I or II who consumed 20% of their daily energy consumption in either almonds or a calorie-matched snack for 24 weeks. A facial photograph and image analysis system was used to obtain standardized high-resolution photographs and information on wrinkle width and severity at 0, 8, 16 and 24 weeks. Measurements of transepidermal water loss (TEWL), skin pigmentation, skin hydration and sebum production were also completed at each visit. Results: The average wrinkle severity was significantly decreased in the almond intervention group at week 16 and week 24 compared to baseline by 15% and 16%, respectively. Facial pigment intensity was decreased 20% in the almond group at week 16 and this was maintained by week 24. There were no significant differences in skin hydration or TEWL in the almond group compared to the control, although sebum excretion was increased in the control group. Conclusion: The daily consumption of almonds may improve several aspects of photoaging such as facial wrinkles and pigment intensity in postmenopausal women. In conclusion, the daily consumption of almonds may contribute to the improvement of facial wrinkles and reduction of skin pigmentation among postmenopausal women with Fitzpatrick skin types I and II.

Background Initially after tattooing, the skin barrier function is broken. However, the long-term impact of clinically healed tattoos on this has never been studied. The aim was to investigate the long-term effect on the skin barrier function in normal tattoos and examples of tattoos with chronic inflammatory complication. Methods Participants were recruited from the "Tattoo clinic" of the Dermatological Department on Bispebjerg Hospital in Denmark, where patients with complicated tattoo reactions are treated. Transepidermal water loss (TEWL), conductance, capacitance, and pH were measured in tattooed skin with regional control measurements in normal non-tattooed skin. Natural moisturizing factor (NMF) was measured in collected tape strips. Results Twenty six individuals with 28 tattoos were included, that is, 23 normal tattoos without any pathologic reaction and 5 tattoos with chronic inflammatory complications. No significant differences were found in tattooed versus non-tattooed skin with respect to TEWL (median values 6.6 vs 7.2 g/m2 /h), conductance (76 vs 78 a.u.), pH (5.94 vs 5.79), and NMF (0.58 vs 0.59 mmol/g protein). Capacitance (64 vs 57 a.u.) was higher in tattooed skin compared to non-tattooed skin (P = 0.006). Similar results were found in tattoos with inflammatory reactions. Conclusion Overall, skin tattoos do not affect the long-term skin barrier function markedly. The skin capacitance was, however, affected in tattooed skin areas compared to non-tattooed skin areas.

BACKGROUND. Adverse cutaneous reactions to skin care products (SCP) are becoming increasingly common, and may be indicative of defective permeability barrier function. AIM. To determine the differences in transepidermal water loss rates (TEWL) between skin patch positive versus negative to skin care products in normal Chinese females. METHODS. Skin patch test reactions to nine skin care products were assessed in 65 normal Chinese females. Correlations of cutaneous reactions to a panel of nine foreign and domestic SCP with permeability barrier function and stratum corneum (SC) hydration levels were analyzed. RESULTS. Out of 65 subjects, 24 (37%) displayed positive reactions to one or more SCP. However, the occurrence of positive reactions to patch tests did not correlate with either transepidermal water loss rates or SC hydration levels. CONCLUSIONS. Though a substantial proportion of normal females display adverse reactions to SCP, this problem cannot be attributed to differences in the qualities of their epidermal permeability barriers, and therefore, these reactions more likely reflect the potential adverse events of the SCP themselves. However, further studies in large cohort of both males and females would be helpful to ascertain whether TEWL levels can predict cutaneous reactions to SCP.

Background Transient Receptor Potential Vanilloid 1 (TRPV1) is known to mediate itch and neurogenic inflammation, but the role of TRPV1 in psoriasiform dermal inflammation is poorly understood. Objective To investigate the function of TRPV1 in imiquimod (IMQ)-induced psoriasiform dermatitis (PsD) in mice. Methods Following daily treatment of topical IMQ cream for consecutive 5 days in C57BL/6 wide-type (WT) and TRPV1 gene knockout (KO) mice, we assessed the psoriasis severity index (PSI) scores, transepidermal water loss (TEWL), dermal inflammatory infiltrates, as well as gene expression levels for psoriasis related genes in mouse skin lesions. Results Compared with WT mice, the clinical and TEWL scores, the extent of skin hyperplasia, the area of Munro microabscesses (MM) and angiogenesis of psoriasis were all significantly decreased in TRPV1 KO mice triggered with IMQ, suggesting a reduction in skin inflammation and barrier defects. In addition, the infiltration of CD45+ leukocytes, mast cells as well as CD3+ T cells was all reduced in the IMQ-treated skin of TRPV1 KO mice. Quantitative Real-time PCR (RT-qPCR) revealed that expression levels of IL-1β, IL-6, IL-23, S100A8 were decreased while IL-10 was increased in TRPV1 KO mice. Conclusions In summary, key markers of psoriatic inflammation and epidermal hyperplasia are reduced in TRPV1 KO mice, indicating the involvement of TRPV1 in the psoriasiform inflammation and suggesting its potential as a therapeutic target.

O estudo da barreira cutânea e de suas propriedades ganhou impulso a partir da década de 60, com estudos que apontaram sua resistência de forma isolada e suas propriedades com relação à permeação cutânea. Paralelamente, a descrição dos corpos de Odland auxiliou a compreensão da manutenção da estabilidade da camada córnea. O modelo brick & mortar, em que os corneócitos são os tijolos e o cimento são os lipídeos intercelulares, é o mais aceito, até o momento. Atualmente, há evidências consistentes de que o estrato córneo é uma estrutura metabolicamente ativa e exerce funções adaptativas. A barreira cutânea também tem um papel na resposta inflamatória, com ativação de melanócitos, angiogênese e fibroplasia, cuja intensidade depende, basicamente, da intensidade da agressão. As anormalidades da barreira cutânea da dermatite atópica são clinicamente observáveis pela presença de pele seca, achado muito frequente e significativo, que constitui parâmetro iagnóstico e de acompanhamento. O grau de hidratação da camada córnea, assim como a perda de água transepidérmica (transepidermal water loss - TEWL), estão relacionados com o grau de dano à barreira, constituindo parâmetros biofísicos que permitem acompanhar os pacientes de maneira não invasiva e com maior grau de sensibilidade.Research about the skin barrier and its properties has increased significantly since the 60s, with studies that indicated its resistance when isolated, as well as its particularities in relation to skin permeability. At the same time, description of Odland bodies helped to understand how stratum corneum stability is maintained. The “brick and mortarâ€� model is the most accepted so far. In this analogy, the corneocytes are the bricks and the intercellular lipids are the mortar. Currently, there is concrete evidence that the stratum corneum is an active metabolic structure that holds adaptive functions, interacting dynamically with the underlying epidermal layers. The skin barrier also plays a role in the inflammatory response through melanocyte activation, angiogenesis, and fibroplasia. The intensity of this response will essentially depend on the severity of the injury. Skin barrier abnormalities in atopic dermatitis are clinically observed by the presence of dry skin, a common and significant symptom which constitutes a diagnostic and monitoring parameter. The stratum corneum hydration level and transepidermal water loss are associated with the level of damage to the barrier, representing biophysical parameters. These parameters help doctors monitor patients in a less invasive and more sensitive manner.

Gas exchange capabilities of polymethylpentene membrane lungs (MLs) worsen over time. ML deterioration is related to protein deposit and clot formation. Condensation and trapping of water vapor inside ML hollow fibers might affect ML performances as well. Increasing sweep gas flow (GF) could remove such fluid. The purpose of this study was to evaluate the effects on ML gas exchange of a recruitment maneuver (RM) based on a brief increase in GF, during veno-venous ECMO support. Short-term (15 min) effects of 20 RMs were assessed. RM raised ML CO2 removal from 149 ± 37 to 174 ± 41 ml/min (p < 0.001). Conversely, RM did not improve ML O2 transfer (155 ± 31 and 158 ± 31 ml/min before and after RM, respectively). ML outlet pCO2 decreased after RM from 51.2 ± 5.8 to 45.8 ± 5.4 mmHg (p < 0.001), while ML outlet pO2 increased from 520 ± 61 to 555 ± 51 mmHg (p < 0.001). Both ML dead space and shunt fractions decreased from 47.8 ± 15.3 to 29.6 ± 14.7 % (p < 0.001) and from 8.8 ± 4.2 to 7.0 ± 3.8 % (p < 0.001), respectively. Furthermore, a subset of 5 RMs was evaluated on a 6-h time frame. The beneficial effects on ML performances due to the RM gradually diminished and waned over a 6-h interval after the RM. The RM improved ML CO2 removal substantially, albeit temporarily. ML oxygenation performance was marginally affected.

Synopsis Multiple stressors, both abiotic and biotic, often are experienced simultaneously by organisms in nature. Responses to these stressors may share signaling pathways (‘‘cross-talk’’) or protective mechanisms (‘‘cross-tolerance’’). Temperate and polar insects that must survive the winter experience low temperatures accompanied by additional abiotic stressors, such as low availability of water. Cold and desiccation have many similar effects at a cellular level, and we present evidence that the cellular mechanisms that protect against cold stress also protect against desiccation, and that the responses to cold and dehydration likely evolved as cross-tolerance. By contrast, there are several lines of evidence suggesting that low temperature stress elicits an upregulation of immune responses in insects (and vice versa). Because there is little mechanistic overlap between cold stress and immune stress at the cellular level, we suggest that this is cross-talk. Both cross-talk and cross-tolerance may be adaptive and likely evolved in response to synchronous stressors; however, we suggest that cross-talk and cross-tolerance may lead to different responses to changes in the timing and severity of multiple stress interactions in a changing world. We present a framework describing the potentially different responses of cross-tolerance and cross-talk to a changing environment and describe the nature of these impacts using interaction of cold-desiccation and cold-immunity in overwintering insects as an example.

As recommended by OECD Guidelines, percutaneous penetration studies consider intact skin, but rarely injured skin. Recent years have witnessed a growing concern for these two types of dermal exposure in the industry, particularly in the nuclear industry. The aim of this study was to show that a method based on an in vitro device can be used to realistically assess how skin-barrier alterations caused by occupational accidents can modify the percutaneous penetration and distribution of radionuclides, particularly uranium. Wounds encountered in the nuclear industry (i.e., nitric acid burns and abrasion) were simulated on hairless rat skin. Skin-barrier alterations were characterized by means of a histological study and by measuring transepidermal water loss (TEWL) and skin thickness. The percutaneous penetration of uranyl nitrate through intact or injured skin biopsies was then measured in vitro. The maximum uranium flux values obtained for intact skin, skin abrasion with stratum corneum removal, and skin exposed to 2 N HNO(3), 5 N HNO(3), and 14 N HNO(3) were, respectively, 0.6 +/- 0.02, 1.2 +/- 0.03, 1.2 +/- 0.04, 42.0 +/- 1.0, and 174.0 +/- 8.7 ng.cm(-2).h(-1). These results demonstrated that the percutaneous absorption of uranium increased with the increased impairment of the stratum corneum. TEWL, combined with maximum uranium flux values measured in vitro, yielded a good prediction of the percutaneous penetration of uranium through injured skin, previously observed in vivo. To conclude, this in vitro assay provides a conservative estimate of the percutaneous diffusion of uranium through intact or injured skin, making it a good alternative method for toxicological studies and risk assessments.

O estudo da barreira cutânea e de suas propriedades ganhou impulso a partir da década de 60, com estudos que apontaram sua resistência de forma isolada e suas propriedades com relação à permeação cutânea. Paralelamente, a descrição dos corpos de Odland auxiliou a compreensão da manutenção da estabilidade da camada córnea. O modelo brick & mortar, em que os corneócitos são os tijolos e o cimento são os lipídeos intercelulares, é o mais aceito, até o momento. Atualmente, há evidências consistentes de que o estrato córneo é uma estrutura metabolicamente ativa e exerce funções adaptativas. A barreira cutânea também tem um papel na resposta inflamatória, com ativação de melanócitos, angiogênese e fibroplasia, cuja intensidade depende, basicamente, da intensidade da agressão. As anormalidades da barreira cutânea da dermatite atópica são clinicamente observáveis pela presença de pele seca, achado muito frequente e significativo, que constitui parâmetro iagnóstico e de acompanhamento. O grau de hidratação da camada córnea, assim como a perda de água transepidérmica (transepidermal water loss - TEWL), estão relacionados com o grau de dano à barreira, constituindo parâmetros biofísicos que permitem acompanhar os pacientes de maneira não invasiva e com maior grau de sensibilidade. Research about the skin barrier and its properties has increased significantly since the 60s, with studies that indicated its resistance when isolated, as well as its particularities in relation to skin permeability. At the same time, description of Odland bodies helped to understand how stratum corneum stability is maintained. The “brick and mortarâ€� model is the most accepted so far. In this analogy, the corneocytes are the bricks and the intercellular lipids are the mortar. Currently, there is concrete evidence that the stratum corneum is an active metabolic structure that holds adaptive functions, interacting dynamically with the underlying epidermal layers. The skin barrier also plays a role in the inflammatory response through melanocyte activation, angiogenesis, and fibroplasia. The intensity of this response will essentially depend on the severity of the injury. Skin barrier abnormalities in atopic dermatitis are clinically observed by the presence of dry skin, a common and significant symptom which constitutes a diagnostic and monitoring parameter. The stratum corneum hydration level and transepidermal water loss are associated with the level of damage to the barrier, representing biophysical parameters. These parameters help doctors monitor patients in a less invasive and more sensitive manner.

En la Estaciôn Experimental Arroyo Loro, durante los anos 2008-2009 se llevaron a cabo dos investigaciones con el objetivo de estimar la polinizaciôn cruzada a través de insectos. El material de siembra utilizado por un 60% de los agricultores de guandul del pais es de baja calidad en cuanto a su pureza varietal. Segùn estimaciones de investigadores, los insectos pueden causar cruzas de hasta un 40% en las plantas de guandul. Los estudios se hicieron con las variedades de guandul 'UASD' (insensible al fotoperiodo, de flor amarilla y vaina verde) e 'IDIAF Navideno' (sensible, de flor roja y vaina marron oscuro) y con el genotipo ALG08-9-4 (insensible, de flor roja y vaina marron oscuro). En cada tratamiento se sembraron dos hileras de las dos variedades en estudio. En una tercera etapa se utilizô la variedad 'UASD' y el genotipo ALG08-9-4. Las abejas fueron los insectos que mâs frecuentaron las plantas durante el dia. De la semilla cosechada de cada tratamiento, se tomô un 3% y se sembrô para determinar si las abejas realizaron cruzamiento entre las variedades. Segùn las evaluaciones en Fi, se encontre» un 15.3 y 24%, de polinizaciôn cruzada, respectivamente, en ambos ensayos. Los datos en F2, segùn la prueba de Chi cuadrado (X2), con una probabilidad de 0.750 a 0.500, se ajusta muy bien a una proportion fenotipica 3:1, es decir un 75% de flores color rojo y un 25% de flores color amarillo, lo cual indica que la herencia es simple y existe dominancia del color de flor rojo.

Changes in body weight in relation to changes in body impedance were studied in six male and four female patients before and during dialysis. Before dialysis, fat-free mass from skinfolds was 46.5 +/- 6.8 kg, and total body water calculated from bio-electrical impedance was 36.9 +/- 5.2 kg. Body water expressed as a percentage of fat-free mass was calculated to be 80 +/- 4%. Mean weight loss, which was assumed to be only loss of water, was 2.7 +/- 0.7 kg. Total body impedance increased by 80 +/- 16 omega from 495 +/- 39 omega to 575 +/- 47 omega. Weight loss and increase in body impedance were highly correlated (r = -0.91, P less than 0.001). However, based on prediction formulas for total body water from bio-electrical impedance, the observed weight (water) loss should be associated with an increase in impedance of only 39 +/- 11 omega. It is concluded that the impedance value before dialysis is a relatively low value, due to the low specific resistivity of the excess of extra-cellular water in the body before dialysis. As a consequence, prediction formulas for body composition from bio-electrical impedance, developed in normal hydrated subjects, overestimate body composition (total body water, fat-free mass) in subjects with oedema.

For comparison of the evaporative water loss through wound coverings, it is necessary to have an accurate and reliable method of measurement. The water vapour permeance (WVP), obtained with the Evaporimeter, meets these requirements, under both in vitro and in vivo circumstances.

For comparison of the evaporative water loss through wound coverings, it is necessary to have an accurate and reliable method of measurement. The water vapour permeance (WVP), obtained with the Evaporimeter, meets these requirements, under both in vitro and in vivo circumstances.

For comparison of the evaporative water loss through wound coverings, it is necessary to have an accurate and reliable method of measurement. The water vapour permeance (WVP), obtained with the Evaporimeter, meets these requirements, under both in vitro and in vivo circumstances.