Screening of male patients with autism spectrum disorder for creatine transporter deficiency

Creatine deficiency syndromes (CDS) are newly identified genetic disorders that result in neurological impairment of cognition and communication. The purpose of our study was to screen 100 male subjects with autism spectrum disorder for mutations in the SLC6A8 gene in order to determine the frequency of this genetic disorder in this population. One hundred males ages 3-18 years diagnosed with autism spectrum disorder based on DSM-IV criteria were recruited. DNA sequence analysis was performed on all subjects for creatine transporter gene (SLC6A8) defects. One subject had a novel unclassified variant in the SLC6A8 gene exon 13: c.1890G>C. Given that autistic features are found in a number of patients with CDS, SLC6A8 deficiency as well as the treatable forms of CDS should be included in the differential diagnosis of patients with autism spectrum disorder.     

Control of electrostatic interactions between F-actin and genetically modified lysozyme in aqueous media

The aim for deterministic control of the interactions between macroions in aqueous media has motivated widespread experimental and theoretical work. Although it has been well established that like-charged macromolecules can aggregate under the influence of oppositely charged condensing agents, the specific conditions for the stability of such aggregates can only be determined empirically. We examine these conditions, which involve an interplay of electrostatic and osmotic effects, by using a well defined model system composed of F-actin, an anionic rod-like polyelectrolyte, and lysozyme, a cationic globular protein with a charge that can be genetically modified. The structure and stability of actin-lysozyme complexes for different lysozyme charge mutants and salt concentrations are examined by using synchrotron x-ray scattering and molecular dynamics simulations. We provide evidence that supports a structural transition from columnar arrangements of F-actin held together by arrays of lysozyme at the threefold interstitial sites of the actin sublattice to marginally stable complexes in which lysozyme resides at twofold bridging sites between actin. The reduced stability arises from strongly reduced partitioning of salt between the complex and the surrounding solution. Changes in the stability of actin-lysozyme complexes are of biomedical interest because their formation has been reported to contribute to the persistence of airway infections in cystic fibrosis by sequestering antimicrobials such as lysozyme. We present x-ray microscopy results that argue for the existence of actin-lysozyme complexes in cystic fibrosis sputum and demonstrate that, for a wide range of salt conditions, charge-reduced lysozyme is not sequestered in ordered complexes while retaining its bacterial killing activity.     

Sterilization: would your facility pass a standards audit?

PROPER STERILIZATION of reusable medical instruments, supplies, and devices and maintaining the sterility of these items until they are used are critical aspects of infection control. To minimize risk, perioperative managers should perform sterilization audits to test their facilities.THIS ARTICLE guides the reader through a systematic, comprehensive, sterilization audit that evaluates facility design, personnel training, and processing procedures. AORN J 87 (January 2008) 176-182. © AORN, Inc, 2008.     

Audiovisual facilitation of clinical knowledge: a paradigm for dispersed student education based on Paivio's Dual Coding Theory

This article explores the application of Paivio's Dual Coding Theory (DCT) as a scientifically sound rationale for the effects of multimedia learning in programs of nurse anesthesia. We explore and highlight this theory as a practical infrastructure for programs that work with dispersed students (ie, distance education models). Exploring the work of Paivio and others, we are engaged in an ongoing outcome study using audiovisual teaching interventions (SBVTIs) that we have applied to a range of healthcare providers in a quasiexperimental model. The early results of that study are reported in this article. In addition, we have observed powerful and sustained learning in a wide range of healthcare providers with our SBVTIs and suggest that this is likely explained by DCT.     

When Enough is Still Not Enough

The Journal of Behavioral Health Services & Research -     

Are hip protectors correctly positioned in use?

There are many designs of hip protectors ranging from small elliptical shaped hard shell designs to large circular soft pads. They are held in position usually by being contained in a close fitting pocket on a garment that patients wear all the time they are at risk of sustaining a fracture of the hip if they fall onto the area of the greater trochanter (GT). It is important for the function of the hip protector that the pad element is positioned over the GT when the subject falls onto a surface such as the floor so as to provide the maximal protection by reducing the large forces transmitted to the femoral neck that lead to the fracture of the bone. In this study, anatomical measurements show where the GT is relevant to the centre of the hip protector, and position and movement studies have shown that generally the hard shell design of the hip protector lies posterior and proximal to the GT both for erect and flexed positions of the hip. The position of the GT relevant to the anterior superior iliac crest was established using ultrasound examinations on control and patients admitted with a fracture of the hip due to a fall. The diagonal surface distance for the three groups of test subjects was approximately 12 cm and a template was developed that could be used to locate the GT. A 'zone' of GT position and movement has been established relative to the anterior superior iliac crest, and designers of garments should ensure that this zone is within the area of protection provided by their hip protector pad design.     

Selective X‐ray contrast enhancement of the spleen of living mice mediated by gold nanorods

Gold nanomaterials (AuNPs) represent a promising new class of contrast agents for X‐ray computed tomographic (CT) imaging in both research and clinical settings. These materials exhibit superior X‐ray absorption properties compared with other iodinated agents, and thus require lower injection doses. Gold is nonimmunogenic and therefore contributes to safety profile in living specimens. Unfortunately, most reports on the use of AuNPs as X‐ray CT enhancers only demonstrate marginal enhancement of the intended anatomical structure. In this study, we demonstrate the dramatic properties of gold nanorods (GNR) to serve as robust X‐ray CT contrast‐enhancing agent for selective imaging of the spleen. These organ‐specific uptake properties were delineated by performing longitudinal CT imaging of living mice that were dosed with GNR at 2 day intervals. Rapid uptake in spleen was noted within 12 h of first systemic administration with a change in contrast enhancement of 90 Hounsfield units (ΔHU = 90) and with two subsequent injections a total contrast enhancement of over 200 HU was observed. The resulting images provide excellent contrast that will enable the detailed anatomical visualization and study of a range of pre‐clinical models of spleen disease including infection and cancer. Copyright © 2014 John Wiley & Sons, Ltd.     

Regulated secretion of glycosylated human ferritin from hepatocytes

Serum ferritin has been used widely in clinical medicine chiefly as an indicator of iron stores and inflammation. Circulating ferritin also can have paracrine effects. Despite the clinical significance of serum ferritin, its secretion remains an enigma. The consensus view is that serum ferritin arises from tissue ferritins--principally ferritin light--which can be glycosylated. Ferritin heavy and light chains are cytosolic proteins that form cages of 24 subunits to store intracellular iron. We show that ferritin light is secreted when its expression is increased in stable, transfected HepG2 cells or adenovirus-infected HepG2 cells. Export occurs through the classical secretory pathway and some chains are N-glycosylated. Ferritins do not need to form cages prior to secretion. Secretion is blocked specifically, effectively, and rapidly by a factor in serum. The timing of this inhibition of ferritin secretion suggests that normally cytosolic ferritin L is targeted to the secretory pathway during translation despite the absence of a conventional signal sequence. Thus, secretion of glycosylated and unglycosylated ferritin is a regulated and not a stochastic process.