Use of a virtual integrated environment in prosthetic limb development and phantom limb pain.

Patients face two major difficulties following limb loss: phantom limb pain (PLP) in the residual limb and limited functionality in the prosthetic limb. Many studies have focused on decreasing PLP with mirror therapy, yet few have examined the same visual ameliorating effect with a virtual or prosthetic limb. Our study addresses the following key questions: (1) does PLP decrease through observation of a 3D limb in a virtual integration environment (VIE) and (2) can consistent surface electromyography (sEMG) signals from the VIE drive an advanced modular prosthetic limb (MPL)? Recorded signals from the residual limb were correlated to the desired motion of the phantom limb, and changes in PLP were scored during each VIE session. Preliminary results show an overall reduction in PLP and a trend toward improvement in signal-to-motion accuracy over time. These signals allowed MPL users to perform a wide range of hand motions.

Membrane-active peptides and the clustering of anionic lipids.

There is some overlap in the biological activities of cell-penetrating peptides (CPPs) and antimicrobial peptides (AMPs). We compared nine AMPs, seven CPPs, and a fusion peptide with regard to their ability to cluster anionic lipids in a mixture mimicking the cytoplasmic membrane of Gram-negative bacteria, as measured by differential scanning calorimetry. We also studied their bacteriostatic effect on several bacterial strains, and examined their conformational changes upon membrane binding using circular dichroism. A remarkable correlation was found between the net positive charge of the peptides and their capacity to induce anionic lipid clustering, which was independent of their secondary structure. Among the peptides studied, six AMPs and four CPPs were found to have strong anionic lipid clustering activity. These peptides also had bacteriostatic activity against several strains (particularly Gram-negative Escherichia coli) that are sensitive to lipid clustering agents. AMPs and CPPs that did not cluster anionic lipids were not toxic to E. coli. As shown previously for several types of AMPs, anionic lipid clustering likely contributes to the mechanism of antibacterial action of highly cationic CPPs. The same mechanism could explain the escape of CPPs from intracellular endosomes that are enriched with anionic lipids.

At a threshold: making decisions when you don't have all the answers.

Many people who sustain a brain injury also lose decisional capacity. They need someone who will be a partner with clinicians in making decisions on their behalf. This article reviews ethical aspects of decision making; the legal foundation in the United States for surrogate decision making; the experience of surrogate decision making on behalf of people who have a brain injury, including similarities and differences between such decision making for the dying and for those who have a brain injury; and ways to approach intractable disagreements between surrogate or family and clinicians. It provides guidelines for clinicians and surrogates and suggests topics for research. Two people who have suffered a brain injury and the spouse of one are coauthors.

Monitoring of technical oils in supercritical CO(2) under continuous flow conditions by NIR spectroscopy and multivariate calibration.

Metal parts and residues from machining processes are usually polluted with cutting or grinding oil and have to be cleaned before further use. Supercritical carbon dioxide can be used for extraction processes and precision cleaning of metal parts, as developed at Forschungszentrum Karlsruhe. For optimizing and efficiently conducting the extraction process, in-line analysis of oil concentration is desirable. Therefore, a monitoring method using fiber-optic NIR spectroscopy in combination with PLS calibration has been developed. In an earlier paper we have described the instrumental set-up and a calibration model using the model compound squalane in the spectral range of the CH combination bands from 4900 to 4200cm(-1). With this model only poor prediction results were obtained if applied to technical oil samples in supercritical CO(2). In this paper we describe a new calibration model, which was set up for the squalane/carbon dioxide system covering the 323-353K temperature and the 16-35.6MPa pressure range. Here, calibration data in the spectral range from 6100 to 5030cm(-1) have been used. This range includes the 5100cm(-1) CO(2) band of the Fermi triad as well as the hydrocarbon 1st overtone CH stretching bands, where spectral features of oil compounds and squalane are more similar to each other. The root mean-squared error of prediction obtained with this model is 4mgcm(-3) for carbon dioxide and 0.4mgcm(-3) for squalane, respectively. The utilizability of the newly developed PLS calibration model for predicting the oil concentration and CO(2) density of solutions of technical oils in supercritical carbon dioxide has been tested. Three types of "real world" cutting and grinding oil formulations were used in these experiments. The calibration proved to be suitable for determining the technical oil concentration with an error of 1.1mgcm(-3) and the CO(2) density with an error of 6mgcm(-3). Therefore, it seems possible to apply this in-line analytical approach on the basis of a cost-effective and time-saving model compound calibration for the surveillance of real world de-oiling and other extraction process based on supercritical carbon dioxide, and furthermore to establish an automated process termination criterion based on this technique.

Promoting a good death for persons with dementia in nursing facilities: family caregivers' perspectives.

The experience of dying from Alzheimer's disease (AD) in a nursing home setting is a poorly understood phenomenon. Fifty-seven family member caregivers of persons with Alzheimer's disease, who had died as a resident in a national nursing home chain, participated in a structured telephone interview. Despite the belief that their loved one had died with dignity, 16 out of 57 (28%) family member caregivers believed that their loved one had not experienced a good death. This article reviews the definition of a good death and the six themes of a good death found in the literature: pain and symptom management; clear decision making; preparation for death; completion; contributing to others; and affirmation of the whole person. Five standards for evaluating the quality of an anticipated death are discussed in relation to the experiences of the persons with AD. Finally, recommendations for how nurse administrators and other members of the healthcare team can promote a positive death experience for a person with AD are proposed.

Prognostic value of codon 918 (ATG-->ACG) RET proto-oncogene mutations in sporadic medullary thyroid carcinoma.

We have determined the frequency of 918 RET proto-oncogene mutations (ATG-->ACG) in primary MTC tumors and metastases and correlated the presence or absence of this mutation with the clinical outcome of patients suffering from sporadic medullary thyroid carcinoma (MTC). A total of 197 samples, consisting of both primary tumors and lymph node metastases from 34 patients with sporadic MTC, were collected for PCR analysis of the RET 918 mutation. In 75 of the samples (38%), codon 918 (ATG-->ACG) mutations could be detected. The mutations showed a heterogeneous distribution: 21/34 patients (62%) had mutations in at least 1 tumor sample, and in 13 patients (38%) the mutation was present in all examined samples. Patients were considered 918mt when at least 1 tumor sample showed the RET 918 mutation. These 918mt and 918 wild-type (918wt) patients did not differ significantly concerning sex, age at diagnosis, TNM stage at diagnosis, number of examined tumor samples or follow-up time. However, 918mt patients showed more aggressive development of distant metastases during follow-up (p = 0.032, Fisher's exact test) with decreased metastases-free survival (p < 0.005, log-rank test). Furthermore, 918mt patients had a significantly lower survival rate than 918wt patients (p = 0.048, log-rank test). These data show that the RET codon 918 mutation has a prognostic impact on patients with sporadic MTC which may influence follow-up treatment.

Optimisation of an integrated optical evanescent wave absorbance sensor for the determination of chlorinated hydrocarbons in water.

The suitability of an integrated optical chemical sensor for the determination of highly volatile chlorinated hydrocarbons in aqueous solutions has been proven. The analytes are detected by NIR absorption spectrometry in the evanescent field of an integrated optical strip waveguide generated in a BGG31 (Schott, Germany) glass substrate, which is coated with a hydrophobic polymer superstrate as sensing layer. It has been shown that the sensitivity increases when the refractive index of the superstrate is increased from 1.333 up to 1.46. Different UV-cured polysiloxanes with low cross sensitivity to water have been prepared. Due to the good light transmission properties of the IO-sensors prepared by this method, quantitative measurements have been performed with the model system trichloroethene (TCE) in water. A detection limit of 22 ppm has been found and the sensor response times (t(90)-value) are between five and fourteen minutes for a coating thickness of around 30 microm. The sensor response is totally reversible. The analyte desorbes in air within 2 min. The enrichment of trichloroethene in the polysiloxane coating can be described by film diffusion through the aqueous boundary layer as rate determining step.

Determination of hydrocarbons in water by evanescent wave absorption spectroscopy in the near-infrared region.

An home-made EFA (Evanescent Field Absorbance)-sensor has been tested for the determination of hydrocarbons in water. The investigations have been performed both with crude oil emulsions and petrol solutions. Cuvette and evanescent wave spectra of crude oil and petrol in the near-infrared region are presented and discussed. The concentration of aromatic compounds in crude oil can be determined semiquantitatively by the standard addition method. The sorption behaviour of the hydrocarbons in the cladding of the fiberoptic sensor has been investigated and a correlation between the sensor signal and the concentration of the aqueous hydrocarbon emulsion/solution could be shown. The desorption of the enriched molecules after the measurements is also presented. The petrol molecules evaporate in ambient air so that the sensor is easily regenerated. In case of oil measurements the hydrocarbon molecules cannot be removed by rinsing the sensor with clear water or by evaporating them in ambient air. It has to be regenerated by washing it with a high volatile solvent instead.

Integrated optical NIR-evanescent wave absorbance sensorfor chemical analysis.

A new, long-path integrated optical (IO) sensor for the detection of non-polar organic substances is described. The sensing layer deposited on a planar multimode IO structure is built by a suitable silicone polymer with lower refractive index (RI). It acts as a hydrophobic matrix for the reversible enrichment of non-polar organic contaminants from water or air. Light from the near-infrared (NIR) range is coupled into the planar structure and the evanescent wave part of the light field penetrating into the silicone layer interacts with the enriched organic species. As a result, light is absorbed at the characteristic frequencies of the corresponding C-H, N-H or O-H overtone and combination band vibrations of the analytes. To perform evanescent field absorbance (EFA) measurements, the arc-shaped strip waveguide structure of 172 mm interaction length was adapted to a tungsten-halogen lamp and an InGaAs diode array spectrograph over gradient index fibers. Dimethyl-co-methly(phenyl)polysiloxanes with varying degrees of phenylation were prepared and used as sensitive coating materials for the IO structure. Light attenuation in the arc-shaped waveguides is high and typical insertion losses in the range of 14-18 dB were obtained. When the coated sensors were brought in contact with aqueous samples, the light transmission decreases, which is due to the formation of H(2)O micro-emulsions in the silicone superstrates. Nevertheless, after reaching constant light transmissions, absorbance spectra of aqueous trichloroethene samples were successfully collected. For gas measurements, where water cross sensitivity problems are absent, the sensitivity of the IO device for trichloroethene was tested as a function of the RI of the silicone superstrate. The slope of the TCE calibration function increases by a factor of 10 by using a poly(methylphenylsiloxane) layer with a RI of 1.449 instead of poly(dimethylsiloxane) (RI: 1.41). A comparison of the IO-EFA and an earlier developed fiber-optic EFA sensor for trichloroethene measurements in the gas phase showed an increase in sensitivity per unit length of the waveguide by a factor of up to 120.

Development of a model for spiritual assessment and intervention.

A multidisciplinary model for making spiritual assessments and interventions is described. The practitioner bases these assessments and interventions upon knowledge gained from philosophy, theology, physiology, psychology, and sociology. Specific assessments are made in the areas of spiritual development and seven practical dimensions of spiritual care. The patient's life experiences, events, and questions shape the nature of spiritual care as the practitioner works toward assisting the patient to maintain or expand the level of spiritual functioning.