Clinical Texting Among Medical Trainees of the University of British Columbia [Formula: see text].

We believe cellphone text messages are commonly used in medical practice whether in rural or urban settings and that clinical photos are often attached to them. Our interest is the use of this technology to provide dermatology service to rural and remote British Columbia. Concern has been expressed about the security of confidential information and adequacy of privacy protection in such an application. We have found little published information about the extent of texting in rural and remote settings (and none in our jurisdiction) or the number and nature of privacy breaches that have actually occurred as a result. To obtain such information, we first set out to survey medical practitioners about their actual use. The results reported here are from medical trainees enrolled with the University of British Columbia who are in both rural and urban settings.

Ethanol perturbs lipid organization in models of stratum corneum membranes: An investigation combining differential scanning calorimetry, infrared and (2)H NMR spectroscopy.

Ethanol is used in a variety of topical products. It is known to enhance the permeability of the skin by altering the ability of the stratum corneum (SC) intercellular membranes to form an effective barrier. In addition, ethanol and other alcohols are key components of antiseptic gels currently used for hand wash. Using infrared and deuterium NMR spectroscopy as well as calorimetry, we have investigated the effect of ethanol on a model membrane composed of lipids representing the three classes of SC lipids, an equimolar mixture of N-palmitoylsphingosine (ceramide), palmitic acid and cholesterol. Ethanol is found to influence the membrane in a dose dependent manner, disrupting packing and increasing lipid motion at low concentrations and selectively extracting lipids at moderate concentrations.

A proton NMR study on the hydration of normal versus psoriatic stratum corneum: linking distinguishable reservoirs to anatomical structures.

The NMR behaviour of normal and psoriatic stratum corneum (SC) was investigated as a function of hydration with the aim of obtaining a better understanding of the role of water in the SC structure. Time domain NMR techniques were employed to identify the signal from water and that from nonaqueous components of the SC, such as lipids and proteins. The signals were investigated as a function of water content. The free induction decay was separated into mobile signal (from water and mobile lipids) and solid signal (from protein and 'solid' lipids). Spin-spin relaxation (T(2)) measurements further separated the mobile domains within the SC. The results suggested that, when water is added to dry SC, it first enters the corneocytes; then, at a hydration of 0.24-0.33 g H(2)O/g SC (normal SC) or 0.12-0.24 g H(2)O/g SC (psoriatic SC), water begins to accumulate in hydrated lipid regions. Water was found to exchange between these two domains on the time scale of a few hundred milliseconds. When compared with normal SC, psoriatic SC had a looser corneocyte structure, a larger mobile lipid component at low hydration and a smaller capacity for corneocyte water.

Phase behavior of an equimolar mixture of N-palmitoyl-D-erythro-sphingosine, cholesterol, and palmitic acid, a mixture with optimized hydrophobic matching.

The phase behavior and lipid mixing properties of an equimolar mixture of nonhydroxylated palmitoyl ceramide (Cer16), palmitic acid (PA), and cholesterol have been investigated using 2H NMR and vibrational spectroscopy. This mixture is formed by the three main classes of lipids found in the stratum corneum (SC), the top layer of the epidermis, and provides an optimized hydrophobic matching. Therefore, its behavior highlights the role played by hydrophobic matching on the phase behavior of SC lipids. We found that, below 45 degrees C, the mixture is essentially formed of coexisting crystalline domains with a small fraction of lipids (less than 20%) that forms a gel or fluid phase, likely ensuring cohesion between the solid domains. Upon heating, there is the formation of a liquid ordered phase mainly composed of PA and cholesterol, including a small fraction of Cer16. This finding is particularly highlighted by correlation vibrational microspectroscopy that indicates that domains enriched in cholesterol and PA include more disordered Cer16 than those found in the Cer16-rich domains. Solubilization of Cer16 in the fluid phase occurs progressively upon further heating, and this leads to the formation of a nonlamellar self-assembly where the motions are isotropic on the NMR time scale. It is found that the miscibility of Cer16 with cholesterol and PA is more limited than the one previously observed for ceramide III extracted from bovine brain, which is heterogeneous in chain composition and includes, in addition to Cer16, analogous ceramide with longer alkyl chains that are not hydrophobically matched with cholesterol and PA. Therefore, it is inferred that, in SC, the chain heterogeneity is a stronger criteria for lipid miscibility than chain hydrophobic matching.

Nurse specialist treatment of eye emergencies: five year follow up study of quality and effectiveness.

The role of specialist nurses in triage, diagnosis and management of emergency eye conditions is well established, and encouraging reports of the safety and effectiveness of such services have been published. Specialist nurses in an emergency eye clinic in the UK seeing >7000 patients per year had been found at initial evaluation to treat 22% of the 1976 patients seen over a three month period without referring on to an ophthalmologist. A repeat of this evaluation five years later found this proportion had dropped to 17% (chi(2) = 16.7, p<0.01). In addition, the initial evaluation had found no incident of any patient having been treated and discharged by the specialist nurses returning to the department due to incorrect diagnosis or mismanagement. By contrast, from the sample 5 years later, 3 patients were identified who returned to the department due to possible misdiagnosis or sub-optimal management. We suggest that provision must be made for continuing professional development of nurses in this type of extended role, and the commitment to ongoing education should be backed up by a system of monitoring and critical incident reporting to facilitate skill maintenance and the life long learning process for specialist nurses.

Fatty acids influence "solid" phase formation in models of stratum corneum intercellular membranes.

Stacked intercellular lipid membranes in the uppermost epidermal layer, the stratum corneum (SC), are responsible for skin's barrier function. These membranes are unique in composition, the major lipids being ceramides (Cer), cholesterol, and free fatty acids (FFA) in approximately equimolar proportions. Notably, SC lipids include chains much longer than those of most biological membranes. Previously we showed that Cer's small hydrophilic headgroup enabled SC model membranes composed of bovine brain ceramide (BBCer), cholesterol, and palmitic acid in equimolar proportion to solidify at pH 5.2. In order to determine the influence of FFA chain length on the phase behavior of such membranes, we used 2H NMR and FT-IR to study BBCer/cholesterol/FFA dispersions containing linear saturated FFA 14-22 carbons long. Independent of chain length, the solid phase dominated the FFA spectrum at physiological temperature. Upon heating, each dispersion underwent phase transitions to a liquid crystalline phase (only weakly evident for the membrane containing FFA-C22) and then to an isotropic phase. The phase behavior, the lipid mixing properties, and the transition temperatures are shown to depend strongly on FFA chain length. A distribution of FFA chain lengths is found in the SC and could be required for the coexistence of a proportion of solid lipids with some more fluid domains, which is known to be necessary for normal skin barrier function.

Interactions of oleic acid and model stratum corneum membranes as seen by 2H NMR.

We have investigated the mechanism through which the penetration enhancer oleic acid acts on stratum corneum (SC) model membranes (bovine brain ceramide:cholesterol:palmitic acid, 1:1:1 molar ratio). We used solid state deuterium nuclear magnetic resonance to monitor such multilamellar SC dispersions containing either cholesterol-d(6), palmitic acid-d(31), or oleic acid-d(2) as a function of both fatty acid concentration (2:2:1:1 and 1:1:1:1 bovine brain ceramide:cholesterol:palmitic acid:oleic acid) and temperature (18-75 degrees C). Our results show that below 40 degrees C, oleic acid (OA) is in an 'isotropic' phase, indicating that it has not incorporated into the lamellar membrane phase. At and above the SC model membrane's crystalline to liquid crystalline melting temperature, T(m)=40-42 degrees C, OA interacts with lamellar SC membranes with a slight dependence on OA concentration. T(m) does not change upon the exposure of the SC model membrane to OA, nor do we see any significant change in membrane chain disorder as monitored by the labelled PA. However, the spectra of both the palmitic acid (PA) and cholesterol SC model membrane components contain an isotropic peak that grows with increasing temperature. Our results thus indicate that oleic acid extracts a fraction of the endogenous SC membrane components, promoting phase separation in the SC membrane system. Reducing the proportion of crystalline lipids and creating more permeable OA-rich domains is a plausible mechanism that explains how OA enhances transdermal penetration.

The effect of ceramide on phosphatidylcholine membranes: a deuterium NMR study.

Biological membranes contain domains having distinct physical properties. We study defined mixtures of phosphoglycerolipids and sphingolipids to ascertain the fundamental interactions governing these lipids in the absence of other cell membrane components. By using (2)H-NMR we have determined the temperature and composition dependencies of membrane structure and phase behavior for aqueous dispersions of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and the ceramide (Cer) N-palmitoyl-sphingosine. It is found that gel and liquid-crystalline phases coexist over a wide range of temperature and composition. Domains of different composition and phase state are present in POPC/Cer membranes at physiological temperature for Cer concentrations exceeding 15 mol %. The acyl chains of liquid crystalline phase POPC are ordered by the presence of Cer. Moreover, Cer's chain ordering is greater than that of POPC in the liquid crystalline phase. However, there is no evidence of liquid-liquid phase separation in the liquid crystalline region of the POPC/Cer phase diagram.