Fetal 4D flow MRI of the great thoracic vessels at 3 Tesla using Doppler-ultrasound gating: a feasibility study.

OBJECTIVES: To evaluate the feasibility of Doppler-ultrasound (DUS)-gated 4D flow MRI of the fetal great thoracic vessels at 3T in a clinical setting. METHODS: Sixteen consecutive fetuses (range 30+4-38+5 weeks) with (n = 11) and without (n = 5) cardiovascular anomalies underwent 4D flow MRI of the great thoracic vessels at 3T. Direct fetal cardiac gating was obtained using a MR-compatible DUS device. 4D flow MRI-based visualisation and quantification of four target regions (ascending aorta (AAo), descending aorta (DAo), main pulmonary artery (MPA), and ductus arteriosus (DA)) were performed using dedicated software. RESULTS: Fetal 4D flow MRI of the great thoracic vessels was successful in 12/16 fetuses (75%) by adopting clinical 4D flow MR protocols in combination with direct fetal cardiac DUS-gating. Four datasets were excluded due to artefacts by fetal movement or maternal breathing. 4D flow MRI-derived time-velocity curves revealed typical arterial blood flow patterns in the aorta. 4D flow quantification was achieved for the pre-defined target regions. Average velocity and flow volume were 21.1 ± 5.2 cm/s and 6.0 ± 3.1 mL/s in the AAo, 24.3 ± 6.7 cm/s and 8.4 ± 3.7 mL/s in the DAo, 21.9 ± 6.4 cm/s and 7.8 ± 4.2 mL/s in the MPA, and 23.4 ± 4.7 cm/s and 5.9 ± 3.6 mL/s in the DA, respectively. CONCLUSIONS: Combination of DUS-gating of the fetal heart and 4D flow MRI allows comprehensive visualisation and quantification of haemodynamics in the fetal great thoracic vessels. DUS-gated fetal 4D flow MRI may provide a new diagnostic approach for prenatal assessment of blood flow haemodynamics. KEY POINTS: • Fetal cardiac Doppler-ultrasound (DUS) gating and 4D flow MRI can be successfully combined. • DUS-gated fetal 4D flow MRI allowed visualisation and evaluation of streamline directionality, illustration of blood flow variations, and pulsatile arterial waveforms in the target vessels. • 4D flow MRI-based visualisation and quantification of the fetal great thoracic vessels were successful and flow metrics agreed with echocardiographic reference values.

Evidence for Sex Differences in Depression, Sexual Attitudes, and Impulsivity as Predictors of Breaking Shelter-in-Place Orders During the COVID-19 Pandemic.

Although the call to understand how sexual behaviors have been impacted by the COVID-19 pandemic has been established as an important area of study, research examining the extent to which gender, sexual attitudes, impulsivity, and psychological distress predicted breaking shelter-in-place (SIP) orders to engage in sexual behaviors with partners residing outside the home is undefined. Obtaining a deeper examination of the variables which predict risky sexual behaviors during SIP has important implications for future research at the intersection of public health, sexuality, and mental health. This study addressed the gap in the literature by considering how partnered sexual behaviors may be used during the COVID-19 pandemic to alleviate stress, as measured by breaking SIP orders for the pursuit of sexual intercourse. Participants consisted of 186 females and 76 males (N = 262) who predominately identified Caucasian/White (n = 149, 57.75%) and heterosexual/straight (n = 190, 73.64%) cultural identities with a mean age of 21.45 years (SD = 5.98, range = 18-65). A simultaneous logistic regression was conducted to examine whether mental health symptoms, sexual attitudes, and impulsivity predicted participants' decision to break SIP orders to engage in sexual intercourse. Based on our results, breaking SIP orders to pursue sexual activities with partners residing outside the home during the COVID-19 pandemic may be understood as an intentional strategy among men with less favorable birth control attitudes to mitigate the effects of depression. Implications for mental health professionals, study limitations, and future areas of research are additionally provided.

Giga-voxel multidimensional fluorescence imaging combining single-pixel detection and data fusion.

Time-resolved fluorescence imaging is a key tool in biomedical applications, as it allows to non-invasively obtain functional and structural information. However, the big amount of collected data introduces challenges in both acquisition speed and processing needs. Here, we introduce a novel technique that allows to acquire a giga-voxel 4D hypercube in a fast manner while measuring only 0.03% of the dataset. The system combines two single-pixel cameras and a conventional 2D array detector working in parallel. Data fusion techniques are introduced to combine the individual 2D and 3D projections acquired by each sensor in the final high-resolution 4D hypercube, which can be used to identify different fluorophore species by their spectral and temporal signatures.

Imaging the optical properties of turbid media with single-pixel detection based on the Kubelka-Munk model.

We present a diffuse optical imaging system with structured illumination and integrated detection based on the Kubelka-Munk light propagation model for the spatial characterization of scattering and absorption properties of turbid media. The proposed system is based on the application of single-pixel imaging techniques. Our strategy allows us to retrieve images of the absorption and scattering properties of a turbid media slab by using integrating spheres with photodiodes as bucket detectors. We validate our idea by imaging the absorption and scattering coefficients of a spatially heterogeneous phantom.

[Compartment syndrome caused by rhabdomyolysis in the context of pychogenic polydipsia]. / Kompartmentsyndrom nach Rhabdomyolyse im Rahmen einer psychogenen Polydipsie.

Psychogenic polydipsia leading to severe hyponatremia is well documented in the literature. This electrolyte disorder can result in encephalopathy, cerebral edema and epileptic seizures. Another rare effect is rhabdomyolysis with all its well known complications (e.g. renal failure, hyperkalemia and cardiac arrhythmia) and even resulting in compartment syndrome due to severe muscle edema. We present the case of a patient with severe hyponatremia caused by psychogenic polydipsia leading to rhabdomyolysis and compartment syndrome.

Regional venous oxygen saturation versus mixed venous saturation after paediatric cardiac surgery.

BACKGROUND: Central venous oxygen saturation (ScvO2) remains the gold standard surrogate for tissue oxygen extraction in paediatric cardiac surgery. Near-infrared spectroscopy (NIRS) has been developed as a non-invasive diagnostic tool for regional oxygen saturation. The aim was to compare regional oxygen saturation measured by NIRS with ScvO2 in postoperative paediatric cardiac patients. METHODS: In this prospective study, we included newborns and infants younger than 45 days undergoing heart surgery. We recorded continuous ScvO2 and NIRS regional saturation placed on the forehead (B) and right flank (S) for 48 h postoperatively. A Bland-Altman's analysis was used to assess the agreement between these measurements. RESULTS: A total of 23 patients were included with a median age of 12 days (2-46) and median weight of 3.1 kg (2.3-4.47). The mean difference (MD) ScvO2- B NIRS was 10.45% with limits of agreement (LOA) -17.23 to 38.13% and ScvO2- S NIRS MD 7.16% with LOA: -25.51 to 39.84%. The single ventricle ScvO2- S NIRS subgroup had MD within ± 5%; however, wide LOA was observed. The remaining subgroups showed MD nearly above ± 5%, with wide LOA. CONCLUSIONS: The regional oxygen saturation of brain and kidney did not match ScvO2 as estimation of global tissue perfusion. Nevertheless, NIRS may still provide information regarding regional circulation that may help in the management of neonatal cardiac surgery patients.

In vitro effects of Ala16Val manganese superoxide dismutase gene polymorphism on human white blood cells exposed to methylmercury.

Environmental contamination by methylmercury (MeHg) is an enormous public health problem in world regions such as Amazonia. MeHg toxic effects seem to be influenced by environmental and genetic factors. However, few studies have evaluated the genetic influences of MeHg toxicity in humans. Therefore, the aim of this study was to evaluate the genetic influence of Ala16Val manganese superoxide dismutase gene polymorphism (Ala16Val-MnSOD) on the cytotoxic effects of in vitro human leukocytes exposed to MeHg. Subjects were selected from 100 individuals aged 26.4 ± 7.3 years genotyped to Ala16Val-MnSOD polymorphism (AA = 6, VV = 6, and AV = 12) to perform in vitro testing using white blood cells (WBCs). Reactive oxygen species production was measured using 2',7'-dichlorofluorescein diacetate fluorimetric assay, and cell viability was measured using MTT assay on WBC samples from the same subjects that were both exposed and not exposed to MeHg (2.5 µM for 6 h). The results showed that AA- and VV-WBCs exposed to MeHg did not display increased reactive oxygen species levels compared to those in cells that were not exposed. However, AV-leukocytes exposed to MeHg displayed increased ROS levels. Cellular viability comparison among genotypes exposed to MeHg showed that the viability of AA-WBCs was lower than that of VV-WBC, with mean values of 3.46 ± 0.13 and 3.08 ± 0.77 (standard error), respectively (P = 0.033), whereas heterozygous cells (AV) displayed intermediate values. This difference was likely due to the higher basal H2O2 production of AA-WBCs compared to that of other genotypes. These results suggest that the Ala16Val-MnSOD polymorphism has toxicogenetic effects in human cells exposed to MeHg.

The inhomogeneous structure of water at ambient conditions.

Small-angle X-ray scattering (SAXS) is used to demonstrate the presence of density fluctuations in ambient water on a physical length-scale of approximately 1 nm; this is retained with decreasing temperature while the magnitude is enhanced. In contrast, the magnitude of fluctuations in a normal liquid, such as CCl(4), exhibits no enhancement with decreasing temperature, as is also the case for water from molecular dynamics simulations under ambient conditions. Based on X-ray emission spectroscopy and X-ray Raman scattering data we propose that the density difference contrast in SAXS is due to fluctuations between tetrahedral-like and hydrogen-bond distorted structures related to, respectively, low and high density water. We combine our experimental observations to propose a model of water as a temperature-dependent, fluctuating equilibrium between the two types of local structures driven by incommensurate requirements for minimizing enthalpy (strong near-tetrahedral hydrogen-bonds) and maximizing entropy (nondirectional H-bonds and disorder). The present results provide experimental evidence that the extreme differences anticipated in the hydrogen-bonding environment in the deeply supercooled regime surprisingly remain in bulk water even at conditions ranging from ambient up to close to the boiling point.

[On prevalence of parenthood in schizophrenia patients]. / Zur Prävalenz von Elternschaft bei schizophrenen Patienten.

A clinical sample of n=370 patients suffering from schizophrenia/schizo-affective disorder (ICD-10 diagnosis F20/25) was investigated as to the prevalence of parenthood along with socio-demographic and clinical aspects. Data analysis yielded that 26.5% of the patients were parents, with women having three times more often children than men. Among those patients who had children, 41% were living together with them in the same household. The results point out that parental roles should be much more considered when treating mentally ill patients with children. This is a vital interest for the parents affected as well as for their children. Furthermore, a working cooperation between adult psychiatry and the youth help system needs to be established.

Disappearance of certain acidic organelles (endosomes and Langerhans cell granules) accompanies loss of antigen processing capacity upon culture of epidermal Langerhans cells.

Freshly isolated epidermal Langerhans cells (LC) can actively process native protein antigens, but are weak in sensitizing helper T cells. During culture, when LC mature into potent immunostimulatory dendritic cells, T cell sensitizing capacity develops but antigen processing capacity is downregulated. Processing of exogenous antigens for class II-restricted antigen presentation involves acidic organelles. We used the DAMP-technique to monitor acidic organelles at the ultrastructural level in fresh, as well as cultured, mouse and human LC. We observed that the loss of antigen processing capacity with culture of LC was reflected by the disappearance of certain acidic organelles, namely endosomes (particularly early ones), and the hitherto enigmatic LC granules ("Birbeck Granules"). Our findings support the notion that endosomes are critical for antigen processing and suggest that LC granules might be involved as well.

Proliferating dendritic cell progenitors in human blood.

CD34+ cells in human cord blood and marrow are known to give rise to dendritic cells (DC), as well as to other myeloid lineages. CD34+ cells are rare in adult blood, however, making it difficult to use CD34+ cells to ascertain if DC progenitors are present in the circulation and if blood can be a starting point to obtain large numbers of these immunostimulatory antigen-presenting cells for clinical studies. A systematic search for DC progenitors was therefore carried out in several contexts. In each case, we looked initially for the distinctive proliferating aggregates that were described previously in mice. In cord blood, it was only necessary to deplete erythroid progenitors, and add granulocyte/macrophage colony-stimulating factor (GM-CSF) together with tumor necrosis factor (TNF), to observe many aggregates and the production of typical DC progeny. In adult blood from patients receiving CSFs after chemotherapy for malignancy, GM-CSF and TNF likewise generated characteristic DCs from HLA-DR negative precursors. However, in adult blood from healthy donors, the above approaches only generated small DC aggregates which then seemed to become monocytes. When interleukin 4 was used to suppress monocyte development (Jansen, J. H., G.-J. H. M. Wientjens, W. E. Fibbe, R. Willemze, and H. C. Kluin-Nelemans. 1989. J. Exp. Med. 170:577.), the addition of GM-CSF led to the formation of large proliferating DC aggregates and within 5-7 d, many nonproliferating progeny, about 3-8 million cells per 40 ml of blood. The progeny had a characteristic morphology and surface composition (e.g., abundant HLA-DR and accessory molecules for cell-mediated immunity) and were potent stimulators of quiescent T cells. Therefore, large numbers of DCs can be mobilized by specific cytokines from progenitors in the blood stream. These relatively large numbers of DC progeny should facilitate future studies of their Fc epsilon RI and CD4 receptors, and their use in stimulating T cell-mediated resistance to viruses and tumors.

Effects and uptake of gold nanoparticles deposited at the air-liquid interface of a human epithelial airway model.

The impact of nanoparticles (NPs) in medicine and biology has increased rapidly in recent years. Gold NPs have advantageous properties such as chemical stability, high electron density and affinity to biomolecules, making them very promising candidates as drug carriers and diagnostic tools. However, diverse studies on the toxicity of gold NPs have reported contradictory results. To address this issue, a triple cell co-culture model simulating the alveolar lung epithelium was used and exposed at the air-liquid interface. The cell cultures were exposed to characterized aerosols with 15 nm gold particles (61 ng Au/cm2 and 561 ng Au/cm2 deposition) and incubated for 4 h and 24 h. Experiments were repeated six times. The mRNA induction of pro-inflammatory (TNFalpha, IL-8, iNOS) and oxidative stress markers (HO-1, SOD2) was measured, as well as protein induction of pro- and anti-inflammatory cytokines (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, GM-CSF, TNFalpha, INFgamma). A pre-stimulation with lipopolysaccharide (LPS) was performed to further study the effects of particles under inflammatory conditions. Particle deposition and particle uptake by cells were analyzed by transmission electron microscopy and design-based stereology. A homogeneous deposition was revealed, and particles were found to enter all cell types. No mRNA induction due to particles was observed for all markers. The cell culture system was sensitive to LPS but gold particles did not cause any synergistic or suppressive effects. With this experimental setup, reflecting the physiological conditions more precisely, no adverse effects from gold NPs were observed. However, chronic studies under in vivo conditions are needed to entirely exclude adverse effects.

Cardiac hormones eliminate some human squamous lung carcinomas in athymic mice.

BACKGROUND: Four cardiac hormones synthesized by the same gene, i.e. atrial natriuretic peptide, vessel dilator, long acting natriuretic peptide and kaliuretic peptide, have anticancer effects in vitro. MATERIALS AND METHODS: These cardiac hormones were infused subcutaneously for 28 days with weekly fresh hormones at 0.3 nM kg(-1) body weight in athymic mice bearing human squamous cell carcinomas. RESULTS: Vessel dilator, atrial natriuretic peptide and kaliuretic peptide each eliminated one in six (17%) of the human squamous cell lung carcinomas. Long-acting natriuretic peptide, although it did not eliminate any of the human squamous cell lung carcinomas did decrease the volume of one carcinoma to only 2% (P < 0.0001) of the untreated carcinomas. The squamous cell lung carcinomas that were not eliminated, with the exception of the one LANP-treated tumour that decreased to only 2% of the volume of the untreated cancers, grew rapidly but their growth velocity compared to controls decreased by 76%, 40%, 38% and 25% in the vessel dilator, atrial natriuretic peptide, kaliuretic peptide and long-acting natriuretic peptide groups respectively (P < 0.05). CONCLUSIONS: Three of four cardiac hormones synthesized by the atrial natriuretic peptide gene can eliminate human squamous cell lung carcinomas in athymic mice when treated subcutaneously for 4 weeks. The 4th cardiac hormone, i.e. long-acting natriuretic peptide, decreased the volume of one squamous cell lung carcinoma to 2% of that of untreated animals, suggesting that it, too, has beneficial effects on squamous cell lung cancers.

[Life satisfaction and subjective importance of life domains in schizophrenia patients: the role of partnership and parenthood]. / Lebenszufriedenheit und subjektive Relevanz von Lebensbereichen bei schizophren Erkrankten.

OBJECTIVE: The aim is to analyze determinants of subjective quality of life in schizophrenia patients. METHODS: Life satisfaction and subjective importance of life domains were assessed in 107 patients (FLZ (M)) and compared with the general population (n = 2974). RESULTS: Schizophrenia patients experience lower levels of life satisfaction as well as less meaningfulness in all life domains. According to the range-of-affect hypothesis, patients with low importance ratings judged their life satisfaction more homogenously. While the presence of a partnership increases life satisfaction, parenthood has only indirect influences on satisfaction. CONCLUSION: Psychiatrists should not only explore life satisfaction, but also the importance of different life domains and the patient's family relations. Supporting beneficial family relations can increase the quality of life in schizophrenia patients.

Long-term responses of canine lungs to acidic particles.

Sixteen beagle dogs were housed in four large chambers under minimum restraint. They were exposed for 16 months to clean air and individual baseline data of markers were obtained. For 13 months, eight dogs were further exposed to clean air and eight dogs for 6 h/d to 1-microm MMAD (mass median aerodynamic diameter) acidic sulfate particles carrying 25 micromol H(+) m(-3) into their lungs. To establish functional responses (lung function, cell and tissue integrity, redox balance, and non-specific respiratory defense capacity), each exposed animal served as its own control. To establish structural responses, the eight non-exposed animals served as controls. Acidic particles were produced by nebulization of aqueous sodium hydrogen sulfate at pH 1.5. Only subtle exposure-related changes of lung function and structure were detected. A significant increase in respiratory burst function of alveolar macrophages points to a marginal inflammatory response. This can be explained by the significant production of prostaglandin E(2), activating cyclooxygenase-dependent mechanisms in epithelia and thus inhibiting lung inflammation. The non-specific defense capacity was slightly affected, giving increased tracheal mucus velocity and reduced in vivo dissolution of moderately soluble test particles. Hypertrophy and hyperplasia of bronchial epithelia were not observed, but there was an increase in volume density of bronchial glands and a shift from neutral to acidic staining of epithelial secretory cells in distal airways. The acidic exposure had thus no pathophysiological consequences. It is therefore unlikely that long-term inhalation of acidic particles is associated with a health risk.

Skin-textile friction and skin elasticity in young and aged persons.

BACKGROUND/PURPOSE: The mechanical properties of human skin are known to change with ageing, rendering skin less resistant to friction and shear forces, as well as more vulnerable to wounds. Until now, only few and contradictory results on the age-dependent friction properties of skin have been reported. This study has investigated in detail the influence of age on the friction of human skin against textiles. METHODS: In vivo skin-friction measurements on a force plate were combined with skin analyses concerning elasticity, hydration, pH value and sebum content. Thirty-two young and 28 aged persons rubbed their volar forearm in a reciprocating motion against various textiles on the force plate, using defined normal loads and sliding velocities, representing clinically relevant contact conditions. RESULTS: Mean friction coefficients ranged from 0.30 +/- 0.04 (polytetrafluoroethylene) to 0.43 +/- 0.04 (cotton/polyester). No significant differences in the friction properties of skin were found between the age groups despite skin elasticity being significantly lower in the aged persons. Skin hydration was significantly higher in the elderly, whereas no significant differences were observed in either skin pH value or sebum content. CONCLUSION: Adhesion is usually assumed to be the dominant factor in skin friction, but our observations imply that deformation is also an important factor in the friction of aged skin. In the elderly, lower skin elasticity and skin turgor are associated with more pronounced skin tissue displacements and greater shear forces during frictional contact, emphasizing the importance of friction reduction in wound-prevention programmes.

Three-dimensional structure of antiphase domains in GaP on Si(0 0 1).

Antiphase domains are three-dimensional crystal defects commonly arising at the interface of III-V semiconductors and Si. While control over their formation has been achieved, the geometry of the antiphase domain itself that is separated from the mainphase of the crystal by the so-called antiphase boundary, has not yet been fully understood. In this work, we first investigate the interface between GaP and Si itself by cross-sectional scanning tunneling microscopy (XSTM) to reveal possible intermixing within an 8 monolayers wide region. Furthermore, we present an extensive analysis combining transmission electron microscopy and XSTM to elucidate the shape of antiphase domains in GaP. To create a true-to-scale, three-dimensional model of an antiphase domain, firstly, plan-view transmission electron microscopy images are drawn on. Subsequently, the progression of many antiphase boundaries through the GaP crystal as viewed from the (1 1 0) and (1 [Formula: see text] 0) cleavage planes is analyzed all the way down to the atomic level by means of XSTM. This enables a detailed analysis of the shape and physical dimensions of the antiphase domains. A typical measured extension in growth directions is found to be a maximum of 60 nm and the maximum measured extension of the base plane in [[Formula: see text] 1 0] and [1 1 0] directions is about 160 nm and 50 nm, respectively. They appear as pyramids with anisotropic base planes whose side facets kink many times.

Uso de vasopresina en el postoperatorio de cirugía de Fontan: inferencias sobre morbimortalidad / Vasopressin use in postoperative Fontan surgery: implications for morbidity and mortality

Introducción: Se ha postulado que el uso de vasopresina tendría efectos beneficiosos en el postoperatorio de cirugía cardiovascular. Objetivo: Evaluar la respuesta a la vasopresina en el postoperatorio (POP) de cirugía de Fontan de nuestra población. Métodos: Estudio de casos y controles anidados en una cohorte retrospectiva. Se incluyeron pacientes con cirugía de Fontan entre 2014 y 2019. Se registraron variables demográficas, datos del cateterismo pre-Fontan, días de asistencia respiratoria mecánica (ARM), necesidad de inotrópicos, diuréticos, diálisis, dieta hipograsa, octreotide, sildenafil y nutrición parenteral total (NPT); balance de fluidos al primer y segundo día POP, necesidad de cateterismo en el POP, días de permanencia de tubo pleural, días de internación, necesidad de reinternación y mortalidad. Se compararon los grupos con y sin vasopresina utilizando la prueba de Mann- Whitney-Wilcoxon test. Se consideró significativa una p < 0.05. Resultados: Del total analizado, 35 pacientes recibieron vasopresina. En el grupo control fueron 58 pacientes con características similares de gravedad sin vasopresina. No se encontraron diferencias en la evolución postoperatoria entre ambos grupos. El grupo con vasopresina recibió en mayor proporción dieta hipograsa. Conclusiones: En nuestra serie el uso de vasopresina no marcó diferencias significativas en términos de morbimortalidad con relación al grupo control (AU)

Introduction: The use of vasopressin has been suggested to have beneficial effects in the postoperative period after cardiovascular surgery. Objective: To evaluate the response to vasopressin in the postoperative period (POP) of Fontan surgery in our population. Methods: Nested case-control study in a retrospective cohort. Patients who underwent Fontan surgery between 2014 and 2019 were included. Demographic variables, pre-Fontan catheterization data, days of mechanical ventilation (MRA), need for inotropics, diuretics, dialysis, low-fat diet, octreotide, sildenafil and total parenteral nutrition (TPN); fluid balance at first and second day POP, need for catheterization at POP, duration of chest tube drainage, days of hospitalization, need for readmission, and mortality were recorded. Groups with and without vasopressin were compared using the Mann-Whitney- Wilcoxon test. A p < 0.05 was considered significant. Results: Of all patients analyzed, 35 received vasopressin. The control group consisted of 58 patients with similar severity characteristics who did not receive vasopressin. No differences were found in the postoperative outcome between the two groups. The vasopressin group received a higher proportion of low-fat diet. Conclusions: In our series the use of vasopressin did not show significant differences in terms of morbidity and mortality compared to the control group (AU)

Influence of epidermal hydration on the friction of human skin against textiles.

Friction and shear forces, as well as moisture between the human skin and textiles are critical factors in the formation of skin injuries such as blisters, abrasions and decubitus. This study investigated how epidermal hydration affects the friction between skin and textiles.The friction between the inner forearm and a hospital fabric was measured in the natural skin condition and in different hydration states using a force plate. Eleven males and eleven females rubbed their forearm against the textile on the force plate using defined normal loads and friction movements. Skin hydration and viscoelasticity were assessed by corneometry and the suction chamber method, respectively.In each individual, a highly positive linear correlation was found between skin moisture and friction coefficient (COF). No correlation was observed between moisture and elasticity, as well as between elasticity and friction. Skin viscoelasticity was comparable for women and men. The friction of female skin showed significantly higher moisture sensitivity. COFs increased typically by 43% (women) and 26% (men) when skin hydration varied between very dry and normally moist skin. The COFs between skin and completely wet fabric were more than twofold higher than the values for natural skin rubbed on a dry textile surface.Increasing skin hydration seems to cause gender-specific changes in the mechanical properties and/or surface topography of human skin, leading to skin softening and increased real contact area and adhesion.

Human and murine dermis contain dendritic cells. Isolation by means of a novel method and phenotypical and functional characterization.

Dendritic cells (DC) comprise a system of cells in lymphoid and nonlymphoid organs that are specialized to present antigens and to initiate primary T cell responses. The Langerhans cell of the epidermis is used as a prototype for studies of DC in the skin. We have characterized a population of DC in human dermis, one of the first examples of these cells in nonlymphoid organs other than epidermis. To identify their distinct functions and phenotype, we relied upon the preparation of enriched populations that emigrate from organ explants of dermis. The dermal cells have the following key features of mature DC: (a) sheet-like processes, or veils, that are constantly moving; (b) very high levels of surface MHC products; (c) absence of markers for macrophages, lymphocytes, and endothelium; (d) substantial expression of adhesion/costimulatory molecules such as CD11/CD18, CD54 (ICAM-1), B7/BB1, CD40; and (e) powerful stimulatory function for resting T cells. Dermal DC are fully comparable to epidermis-derived DC, except for the lack of Birbeck granules, lower levels of CD1a, and higher levels of CD36. DC were also detected in explants of mouse dermis. We conclude that cutaneous DC include both epidermal and dermal components, and suggest that other human nonlymphoid tissues may also serve as sources of typical immunostimulatory DC.