Concordance of the SHEA-IDSA severity classification for Clostridium difficile infection and the ATLAS bedside scoring system in hospitalized adult patients.

PURPOSE: The Society for Healthcare Epidemiology of America and Infectious Diseases Society of America (SHEA-IDSA) guidelines for the treatment of Clostridium difficile infection (CDI) recommend initial treatment of CDI based on disease severity. This severity definition has not been validated or evaluated based on clinical outcomes. The ATLAS scoring system is a validated tool useful in predicting treatment response and mortality in CDI. The main purpose of this study is to evaluate the concordance of the ATLAS scoring system and the SHEA-IDSA staging for CDI severity. METHODS: This was a retrospective study which included hospitalized patients with confirmed CDI. Bivariate analyses compared baseline demographics and clinical information between patients with nonsevere and severe CDI based on the SHEA-IDSA criteria for CDI severity. Kappa scores were calculated to compare the concordance of the two scoring systems in defining CDI severity. Sensitivity and specificity of the ATLAS scoring system to determine CDI severity were calculated using the SHEA-IDSA criteria as the reference standard. RESULTS: Sixty-four patients met inclusion criteria. Of those, 62.5% were classified as mild to moderate CDI, 25% were severe, uncomplicated, and 12.5% were severe, complicated based on SHEA-IDSA criteria. In the bivariate analyses, ATLAS score breakpoints of ≥ 4, ≥ 5, and ≥ 6 revealed moderate agreement with the SHEA-IDSA classification for severity. The sensitivities and specificities for ATLAS scores in predicting CDI severity ranged from 58.3 to 87.5, and 67.5-87.5%, respectively. CONCLUSION: The ATLAS score may be useful in evaluating CDI severity and determining drug therapy selection.

DRAW+SneakPeek: analysis workflow and quality metric management for DNA-seq experiments.

SUMMARY: We report our new DRAW+SneakPeek software for DNA-seq analysis. DNA resequencing analysis workflow (DRAW) automates the workflow of processing raw sequence reads including quality control, read alignment and variant calling on high-performance computing facilities such as Amazon elastic compute cloud. SneakPeek provides an effective interface for reviewing dozens of quality metrics reported by DRAW, so users can assess the quality of data and diagnose problems in their sequencing procedures. Both DRAW and SneakPeek are freely available under the MIT license, and are available as Amazon machine images to be used directly on Amazon cloud with minimal installation. AVAILABILITY: DRAW+SneakPeek is released under the MIT license and is available for academic and nonprofit use for free. The information about source code, Amazon machine images and instructions on how to install and run DRAW+SneakPeek locally and on Amazon elastic compute cloud is available at the National Institute on Aging Genetics of Alzheimer's Disease Data Storage Site (http://www.niagads.org/) and Wang lab Web site (http://wanglab.pcbi.upenn.edu/).

Characterisation of prosthetic feet used in low-income countries.

Eleven kinds of prosthetic feet that were designed for use in low-income countries were mechanically characterised in this study. Masses of the different kinds of prosthetic feet varied substantially. Dynamic properties, including damping ratios and resonant frequencies, were obtained from step unloading tests of the feet while interacting with masses comparable to the human body. Data showed that for walking, the feet can be appropriately modeled using their quasistatic properties since natural frequencies were high compared to walking frequencies and since damping ratios were small. Roll-over shapes, the effective rocker (cam) geometries that the feet deform to under walking loads, were determined using a quasistatic loading technique and a spatial transformation of the ground reaction force's centre of pressure. The roll-over shapes for most of the prosthetic feet studied were similar to the roll-over shape of the SACH (solid-ankle cushioned heel) prosthetic foot. All roll-over shapes showed a lack of forefoot support, which may cause a "drop-off" experience at the end of single limb stance and shorter step lengths of the contralateral limb. The roll-over shapes of prosthetic feet appear useful in characterization of foot function.

Alignment of trans-tibial prostheses based on roll-over shape principles.

The authors examined the roll-over shape alignment hypothesis, which states that prosthetic feet are aligned by matching their roll-over shapes with an "ideal" shape. The "ideal" shape was considered to be the roll-over shape of the able-bodied foot-ankle system. An alignment algorithm and computational alignment system were developed to set trans-tibial alignments based on this hypothesis. Three prosthetic feet with considerably different roll-over shapes were either aligned using the alignment system or not aligned (i.e. used previous foot's alignment), and then were aligned by a team of prosthetists. No significant differences were found between roll-over shapes aligned by the computational alignment system and those based on standard clinical techniques (p = 0.944). Significant differences were found between the "no alignment" shapes and the prosthetist alignment shapes (p = 0.006), and between the "no alignment" shapes and the computational alignment system shapes (p = 0.024). The results of the experiment support the hypothesis that the goal of alignment is to match the prosthetic foot's roll-over shape, as closely as possible, with an "ideal" shape. The hypothesis is also supported by its ability to explain the results of previous studies. Using an "ideal" roll-over shape or surface as a goal for prosthetic alignment could lead to a priori alignment, eliminating the need for alignment hardware in some cases. Being able to build the alignment into a prosthesis without special hardware could be beneficial in low-income countries and in the fabrication of lightweight prostheses for the elderly.

CIR sand casting system for trans-tibial socket.

The authors have developed a trans-tibial socket fabrication system based on the "dilatancy" principle, a process that has been commonly used in forming wheelchair Seating. The CIR Sand Casting System replaces plaster of Paris with sand for forming both a negative sand mould and a positive sand model, which can be modified for either thermoplastic socket formation or resin lamination. Initial clinical trials suggest that fabrication times are approximately 90 minutes from patient evaluation and casting to dynamic alignment. Compatibility with all existing prosthetic components is retained. It is believed the CIR socket fabrication system may be a competitive alternative for prosthetic service providers in developing countries.

Cineplasty as a control input for externally powered prosthetic components.

To achieve significant improvement in the function of electric-powered, upper-limb prostheses, we believe it is necessary to develop better control interfaces with inherent sensory feedback. Small cineplasties, or other surgical procedures that also externalize the force and excursion of a muscle, could potentially provide this superior control. Connecting a muscle to a prosthetic component via a controller that embodies the concept of extended physiological proprioception (EPP) would enable the physiological sensory feedback inherent in the skin, muscle, and other tissues of the cineplasty to inform the user of the state of the prosthesis. Multiple miniature forearm tunnel cineplasties, each with an EPP controller, might enable meaningful independent multifinger control of hand prostheses. At higher levels of amputation (e.g., transhumeral), small pectoral or deltoid cineplasties could augment existing control sources to improve control of multifunctional total arm prostheses. To explore the feasibility of these ideas, we quantified the control capabilities of individuals with preexisting biceps muscle tunnel cineplasties with the use of pursuit tracking experiments. A "proof-of-concept" EPP electric hand prosthesis was also successfully developed for a subject with agonist-antagonist, forearm tendon exteriorization cineplasties. The results of the tracking studies demonstrate numerically the efficacy of control by cineplastized muscles relative to other control approaches.

A preliminary investigation of pelvic obliquity patterns during gait in persons with transtibial and transfemoral amputation.

Differences in pelvic obliquity between small groups of persons with unilateral lower limb amputation and subjects without amputation were analyzed. Kinematic walking data were collected as six males with transtibial amputation and three males with transfemoral amputation walked over a range of speeds. The pelvic obliquity patterns and amplitudes from the groups with amputation were compared to normal data. Results showed that smaller peak-to-peak amplitudes of pelvic obliquity were associated with higher amputation levels. Pelvic drop during early prosthetic-limb stance tended to be smaller than during early sound-limb stance. Most of the subjects with amputation exhibited an obliquity pattern in which the hip on the prosthetic side was raised above the stance-side hip during prosthetic swing phase, indicative of a compensatory action known as hip-hiking. The subjects with transfemoral amputation exhibited this hip-hiking pattern during sound-limb swing phase as well. Results from this study suggest that further investigation is required to determine those limitations of current prosthetic technology that adversely affect pelvic obliquity in the gait of persons with amputation, and to determine if significant benefit can be realized by restoring a normal pattern of pelvic obliquity to the gait of persons with amputation.

Prosthetic foot roll-over shapes with implications for alignment of trans-tibial prostheses.

Roll-over shape is introduced as a significant characteristic of prosthetic feet. The roll-over shapes of the Flexwalk, Quantum, SACH, and SAFE prosthetic feet were determined using three methods; two involving quasi-static loading and one dynamic loading. The results show that foot roll-over shape properties obtained by quasi-static and by dynamic methods are similar. Relationships between foot roll-over shape and the alignment of trans-tibial prostheses are introduced that suggest ways to align trans-tibial prostheses without walking trials and iterations. The relationships may explain what prosthetists attempt to accomplish when they dynamically align a trans-tibial limb. They also explain why prosthetic feet with different mechanical properties usually necessitate different alignments, and may explain why a number of gait studies of trans-tibial amputees do not show major gait differences when walking is executed on various kinds of prosthetic feet.

Games galore.

Gaming is an interactive process that lends itself to the acquisition and application of cognitive, affective, and psychomotor knowledge and skills. The purpose of this article is to identify the rules, game pieces, and players to assist nursing educators to spin the Wheel of Fortune and enhance their training techniques.

An autosomal genomic screen for autism. Collaborative linkage study of autism.

Autism is a severe neurodevelopmental disorder defined by social and communication deficits and ritualistic-repetitive behaviors that are detectable in early childhood. The etiology of idiopathic autism is strongly genetic, and oligogenic transmission is likely. The first stage of a two-stage genomic screen for autism was carried out by the Collaborative Linkage Study of Autism on individuals affected with autism from 75 families ascertained through an affected sib-pair. The strongest multipoint results were for regions on chromosomes 13 and 7. The highest maximum multipoint heterogeneity LOD (MMLS/het) score is 3.0 at D13S800 (approximately 55 cM from the telomere) under the recessive model, with an estimated 35% of families linked to this locus. The next highest peak is an MMLS/het score of 2.3 at 19 cM, between D13S217 and D13S1229. Our third highest MMLS/het score of 2.2 is on chromosome 7 and is consistent with the International Molecular Genetic Study of Autism Consortium report of a possible susceptibility locus somewhere within 7q31-33. These regions and others will be followed up in the second stage of our study by typing additional markers in both the original and a second set of identically ascertained autism families, which are currently being collected. By comparing results across a number of studies, we expect to be able to narrow our search for autism susceptibility genes to a small number of genomic regions. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 88:609-615, 1999.

The influence of stance-phase knee flexion on the vertical displacement of the trunk during normal walking.

OBJECTIVE: To determine the effect of stance-phase knee flexion on the trunk's vertical displacement in normal walking. SUBJECTS: Three able-bodied adult male volunteers. DESIGN: Kinematic data describing the joint centers and joint angles of the legs and pelvis were collected from the subjects. The subjects walked at four target speeds (range, approximately 1.0 to 2.0 m/sec); a minimum of three trials of data at each walking speed were collected and processed. SETTING: Clinical gait analysis laboratory. RESULTS: Stance-phase knee flexion was not found to significantly reduce the peak-to-peak amplitude of the trunk's vertical displacement in normal walking. The reason for this has to do with the timing (ie, phase) of the stance-phase knee flexion wave with respect to the trunk's vertical displacement during the gait cycle. Stance-phase knee flexion in normal walking was found to reduce the mean elevation of the trunk by a few millimeters and to delay the trunk's vertical displacement waveform by about 2% to 6% of the gait cycle from where it would have been otherwise. CONCLUSIONS: Contrary to conventional wisdom, stance-phase knee flexion does not appreciably reduce the amount of vertical movement of the trunk in normal walking.

Fairy tales of storyboarding.

Once upon a time, there were two creative, intelligent, staff development educators who worked in a large hospital in Dayton, Ohio, and who wanted to tell a story about how to share performance improvement initiatives with others. To narrate their story, they used a problem-solving method, a coordinating theme, bright colors, graphics, clip art, photography, data collection, and a board to display their story for "The Fundamentals of Storyboarding." A properly designed poster/storyboard can successfully attract attention, stimulate interest, and impart information. Poster presentations are effective tools for educators to share their knowledge and expertise as well as demonstrate performance-improvement initiatives in their organization. Join these storytellers as they open their book and present the chapters to help create a powerful poster presentation.

Use of diaphragm transducers in the measurement of pressures on soft materials.

Diaphragm pressure transducers are designed to measure pressures in fluids, but have also been applied to measuring pressures on soft materials, such as at the interface between the residual limb of a lower-limb amputee and the supporting surface defined by the prosthetic socket. The reliability and accuracy of Kulite XTM-190 transducer as a pressure monitor on soft materials, such as silicone and Pelite was evaluated in three physical model set-ups. The evaluations included the uniform loading of solid disks of silicone and Pelite, the application of air pressure to the core of a contained thick-walled cylinder made of silicone, and the dynamic indentation of a contained solid silicone cylinder. Sensor measurements in all situations were similar to analytical, iterative or finite element solutions when certain conditions were met. These conditions include: (i) lubricating the interface between the soft material and the supporting structure; (ii) calibrating the transducers under surface and material conditions used during measurements; and (iii) using compatible soft materials (e.g. silicone but not Pelite).

Personality and language characteristics in parents from multiple-incidence autism families.

Several studies have suggested that the genetic liability for autism may be expressed in non-autistic relatives of autistic probands, in behavioral characteristics that are milder but qualitatively similar to the defining features of autism. We employ a variety of direct assessment approaches to examine both personality and language in parents ascertained through having two autistic children (multiple-incidence autism parents) and parents of Down syndrome probands. Multiple-incidence autism parents had higher rates of particular personality characteristics (rigidity, aloofness, hypersensitivity to criticism, and anxiousness), speech and pragmatic language deficits, and more limited friendships than parents in the comparison group. The implications of these findings for future genetic studies of autism are discussed.

Generic, geometric finite element analysis of the transtibial residual limb and prosthetic socket.

Finite element (FE) analysis was used to investigate the stress distribution between the residual limb and prosthetic socket of persons with transtibial amputation (TTA). The purpose of this study was to develop a tool to provide a quantitative estimate of prosthetic interface pressures to improve our understanding of residual limb/prosthetic socket biomechanics and prosthetic fit. FE models of the residual limb and prosthetic socket were created. In contrast to previous FE models of the prosthetic socket/residual limb system, these models were not based on the geometry of a particular individual, but instead were based on a generic, geometric approximation of the residual limb. These models could then be scaled for the limbs of specific individuals. The material properties of the bulk soft tissues of the residual limb were based upon local in vivo indentor studies. Significant effort was devoted toward the validation of these generic, geometric FE models; prosthetic interface pressures estimated via the FE model were compared to experimentally determined interface pressures for several persons with TTA in a variety of socket designs and static load/alignment states. The FE normal stresses were of the same order of magnitude as the measured stresses (0-200 kPa); however, significant differences in the stress distribution were observed. Although the generic, geometric FE models do not appear to accurately predict the stress distribution for specific subjects, the models have practical applications in comparative stress distribution studies.

Broader autism phenotype: evidence from a family history study of multiple-incidence autism families.

OBJECTIVE: Studies of families ascertained through a single autistic proband suggest that the genetic liability for autism may be expressed in nonautistic relatives in a phenotype that is milder but qualitatively similar to the defining features of autism. The objective of this study was to examine behaviors that may define this broader phenotype in relatives ascertained through two autistic siblings. METHOD: The authors used a semistructured family history interview to compare the rates of social and communication deficits and stereotyped behaviors in relatives ascertained through two autistic siblings (families with multiple-incidence autism; 25 families) with the rates in relatives of Down syndrome probands (30 families). RESULTS: Higher rates of social and communication deficits and stereotyped behaviors were found in the relatives in the families with multiple-incidence autism. CONCLUSIONS: These data suggest that further studies should be undertaken to delineate the boundaries of the broader autism phenotype and that this broader phenotype should be included in some future genetic analyses of this disorder.

Analysis of a vertical compliance prosthetic foot.

Mechanical testing of the Re-Flex VSP Foot was conducted on the pylon alone and on the pylon and forefoot system. Values for spring and damping correspond well to values reported in the literature for spring and damping of physiological limbs. Pylon stiffness was 49.4 kN/m for a 600 N subject and 91.4 kN/m for an 800 N subject. The vertical stiffness of the pylon and forefoot together was 31.9 kN/m and 37.8 kN/m, respectively. Gait parameters of two persons with transtibial amputation who used vertically compliant feet for walking, jogging in place, and curb descent were investigated. Ground reaction forces, vertical trunk movement, event timing, and pylon compression were observed. The spring-loaded telescoping pylon was immobilized for half the trials. The trials were repeated the following week with the vertical compliance feature mobilized. Significant differences in vertical trunk motion and timing were found between the prosthetic limb and normal limb, as might be expected. Vertical compliance appeared to cause little change in gait parameters during normal walking. The largest differences appeared during the higher impact events such as fast walking and jogging in place.

A portable, real-time, clinical gait velocity analysis system.

A direct ultrasound ranging system (DURS) has been developed for the quantitative evaluation of gait velocity. DURS consists of a transponder worn by the subject, a base unit infrared (IR) emitter/ultrasound (US) receiver, and a laptop computer. During gait analysis the transponder is worn by the subject at the approximate level of the body center of mass. As the subject walks away from the base unit his or her forward progression is displayed in real-time on the computer. At the end of the walking trial the instantaneous velocity profile, or gait velocigram (GVG), for that trial is displayed on the computer screen. From the GVG, parameters such as, gait speed, cadence, step length, step time, peak-to-peak variation, and time to achieve steady state walking are calculated and displayed. In addition gait deviations are readily apparent on the GVG.