Automated Nucleic Acid Purification for Large Samples

Advancements in the fields of genomic screening, molecular pathology and clinical research have resulted in a major increase in the demand for high quality DNA and RNA. This escalating demand has resulted in a sample preparation bottleneck and an emphasis on the development of new technologies to automate the purification process. Gentra has developed the AUTOPURE LS™ nucleic acid purification instrument, a platform capable of high-throughput sample purification from large samples, such as 10 mL whole blood. This article presents data showing the equivalency of DNA purified using manual and automated processing.     

Analysis of heart-rate variability: a noninvasive predictor of death and poor outcome in patients with severe head injury

BACKGROUND: Analysis of heart-rate variability (HRV) is a promising new technique for noninvasive quantification of autonomic function. We measured HRV in patients with severe head injury to assess its potential as a monitoring tool. METHODS: Analysis of HRV was prospectively done on all intensive care unit patients. Concurrent data on intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were collected. Registry data were reviewed to identify patients with severe head injury, defined as Head/Neck Abbreviated Injury Scale score > or = 4. Mortality, likelihood of discharge to home, ICP, and CPP were compared between patients with abnormal HRV and those without. RESULTS: Low HRV was associated with increased mortality and decreased rate of discharge to home. Abnormal HRV was associated with episodes of increased ICP and decreased CPP. CONCLUSION: Assessment of HRV is a noninvasive method that can be widely used. Abnormal HRV was associated with poor outcome and altered cerebral perfusion. Monitoring of HRV may improve outcome by allowing earlier detection and treatment of intracranial pathology.     

In Search of a Common Core: A Content Analysis of Interventions to Promote Forgiveness.

This article reviews published methods for promoting forgiveness for a broad range of clinical issues. The review revealed a consensus among applied researchers regarding several broad types of interventions to promote forgiveness, namely, (a) defining forgiveness, (b) helping clients remember the hurt, (c) building empathy in clients for the perpetrator, (d) helping clients acknowledge their own past offenses, and (e) encouraging commitment to forgive the offender. Roughly half of the studies also prescribed interventions to help clients overcome unforgiveness (e.g., bitterness, vengefulness) without explicitly promoting forgiveness. Speculations about how to use forgiveness interventions in sensitive and client-supportive ways are advanced on the basis of the findings. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Copper‐Based Nanostructured Coatings on Natural Cellulose: Nanocomposites Exhibiting Rapid and Efficient Inhibition of a Multi‐Drug Resistant Wound Pathogen,A. baumannii,and Mammalian Cell Biocompatibility In Vitro

This paper describes a layer‐by‐layer (LBL) electrostatic self‐assembly process for fabricating highly efficient antimicrobial nanocoatings on a natural cellulose substrate. The composite materials comprise a chemically modified cotton substrate and a layer of sub‐5 nm copper‐based nanoparticles. The LBL process involves a chemical preconditioning step to impart high negative surface charge on the cotton substrate for chelation controlled binding of cupric ions (Cu²⁺), followed by chemical reduction to yield nanostructured coatings on cotton fibers. These model wound dressings exhibit rapid and efficient killing of a multidrug resistant bacterial wound pathogen, A. baumannii, where an 8‐log reduction in bacterial growth can be achieved in as little as 10 min of contact. Comparative silver‐based nanocoated wound dressings–a more conventional antimicrobial composite material–exhibit much lower antimicrobial efficiencies; a 5‐log reduction in A. baumannii growth is possible after 24 h exposure times to silver nanoparticle‐coated cotton substrates. The copper nanoparticle–cotton composites described herein also resist leaching of copper species in the presence of buffer, and exhibit an order of magnitude higher killing efficiency using 20 times less total metal when compared to tests using soluble Cu²⁺. Together these data suggest that copper‐based nanoparticle‐coated cotton materials have facile antimicrobial properties in the presence of A. baumannii through a process that may be associated with contact killing, and not simply due to enhanced release of metal ion. The biocompatibility of these copper‐cotton composites toward embryonic fibroblast stem cells in vitro suggests their potential as a new paradigm in metal‐based wound care and combating pathogenic bacterial infections.     

Raman spectroscopy using a spatial heterodyne spectrometer: proof of concept

The use of a spatial heterodyne interferometer-based spectrometer (SHS) for Raman spectroscopy is described. The motivation for this work is to develop a small, rugged, high-resolution ultraviolet (UV) Raman spectrometer that is compatible with pulsed laser sources and that is suitable for planetary space missions. UV Raman is a particular technical challenge for space applications because dispersive (grating) approaches require large spectrographs and very narrow slits to achieve the spectral resolution required to maximize the potential of Raman spectroscopy. The heterodyne approach of the SHS has only a weak coupling of resolution and throughput, so a high-resolution UV SHS can both be small and employ a wide slit to maximize throughput. The SHS measures all optical path differences in its interferogram simultaneously with a detector array, so the technique is compatible with gated detection using pulsed lasers, important to reject ambient background and mitigate fluorescence (already low in the UV) that might be encountered on a planetary surface where samples are uncontrolled. The SHS has no moving parts, and as the spectrum is heterodyned around the laser wavelength, it is particularly suitable for Raman measurements. In this preliminary report we demonstrate the ability to measure visible wavelength Raman spectra of liquid and solid materials using an SHS Raman spectrometer and a visible laser. Spectral resolution and bandpass are also discussed. Separation of anti-Stokes and Stokes Raman bands is demonstrated using two different approaches. Finally spectral bandpass doubling is demonstrated by forming an interference pattern in both directions on the ICCD detector followed by analysis using a two-dimensional Fourier transform.     

Small-geometry, high-performance, Si-Si1-xGexheterojunction bipolar transistors

Si-Si_1-xGe_x heterojunction bipolar transistors (HBTs) with very heavily doped bases, fabricated using electron-beam lithography to obtain very small feature sizes, are discussed. Emitter, base, and collector epitaxial layers were grown in situ in a lamp-heated, chemical-vapor-deposition reactor. Transistors with common-emitter current gain of approximately 50 and f_t of about 28 GHz have been obtained. Analysis indicates that the frequency response is limited by parasitic resistances and capacitances in the simple demonstration structure used, rather than by the intrinsic device characteristics. Simple ring oscillators have been fabricated using HBTs in the inverse-active mode of operation     

Responses to interpersonal transgressions in families: Forgivingness, forgivability, and relationship-specific effects.

Social relations analyses examined the relative importance of forgivingness (disposition to forgive others), forgivability (tendency to obtain forgiveness from others), and relationship effects in determining family members' transgression-related interpersonal motivations (TRIMs) and their perceptions of others' TRIMs toward them (PTRIMs). In 2 studies, the individual and dyadic predictors of these components and their relative importance differed by family role (father, mother, or early adolescent child). Dispositional tendencies accounted for the most variance in father and child forgiveness, whereas mothers' TRIMs and PTRIMs were more strongly determined by relationship and partner effects. Personality correlates of forgivingness and forgivability were moderated by family role. The findings point to the need to embed the study of forgiveness in more complex psychosocial contexts. The theoretical, methodological, and applied implications of this conclusion are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ex vivo gene therapy prevents chronic graft vascular disease in cardiac allografts

There continues to be considerable effort towards the construction of compound libraries targeted for the inhibition of protease enzymes. New tag-encoding methods for library deconvolution have been applied to this problem and there has been particular interest in novel solid-phase linkers for the introduction of key pharmacophore groups required for protease inhibition. Recent reports have tended to focus on nonpeptidic libraries, and, notably, structure-based design methods are now being applied to direct library design.