Multicenter Diagnostic Accuracy Evaluation of the Luminex Aries Real-Time PCR Assay for Group B Streptococcus Detection in Lim Broth-Enriched Samples.

The vertical transmission of group B Streptococcus (GBS) strains causing neonatal sepsis is one of the leading reasons for neonatal mortality worldwide. The gold standard for GBS detection is enriched culture with or without the aid of chromogenic agars. Given the high risk for morbidity and mortality in this population, high assay sensitivity is required to prevent the personal and economic costs of GBS disease. Nucleic acid amplification tests (NAATs) allow for objective determination of GBS colonization with a sensitivity and a specificity higher than those of traditional culture methods. In this study, we determined the analytical and clinical performance of the Aries GBS assay compared to those of the enrichment culture method, biochemical identification, and the NAATs used at the study sites. Remnant Lim broth samples were used to perform the Aries assay and reference testing. Upon first testing using enriched culture as the reference standard, the Aries GBS assay identified GBS with a 96.1% sensitivity (95% confidence interval [CI], 91.2 to 98.7%) and a 91.4% specificity (95% CI, 88.8 to 93.6%). The test performed with 100% positive agreement (95% CI, 83.2 to 100%) compared to the results of the BD Max GBS assay and 98.0% positive agreement (95% CI, 89.2 to 99.9%) compared to the results of the Cepheid Xpert GBS LB test. Repeatability and reproducibility were maintained in intra- and interlaboratory testing, regardless of the instrument, module, or user who performed the test. The Aries GBS assay can be set up in less than 5 min and produces results in 2 h. The easy setup, with minimal hands-on time, and high assay sensitivity and specificity make this a useful testing option for GBS screening in prepartum women.

Examining sedentary time as a risk factor for cardiometabolic diseases and their markers in South Asian adults: a systematic review.

OBJECTIVES: The objective was to systematically review the literature to determine whether sedentary time was associated with cardiometabolic diseases and their risk factors among South Asian adults. METHODS: Six electronic databases were searched to identify all studies that examined the association between sedentary time and cardiometabolic diseases (e.g., diabetes, cardiovascular disease) and their risk factors [e.g., body mass index (BMI), waist circumference (WC), lipids, blood pressure (BP), glucose] among South Asian adults. Two independent reviewers performed abstract/full-text screening, data abstraction, and quality assessments. RESULTS: Searching identified 1757 potential articles; 22 were used in the analysis. Greater sedentary time was associated with an increased likelihood of diabetes (n = 5), higher BMI (n = 13), WC (n = 3), BP (n = 2), and glucose (n = 4). Thirteen out of 22 studies were of higher quality. CONCLUSION: Results identified a trend whereby greater sedentary time was associated with an increased risk for diabetes, and several other cardiometabolic risk factors among South Asian adults. High quality studies are needed to identify whether risk factors are independent of physical activity levels to inform culturally-specific interventions for South Asians.

Loss of neurofilaments alters axonal growth dynamics.

The highly regulated expression of neurofilament (NF) proteins during axon outgrowth suggests that NFs are important for axon development, but their contribution to axon growth is unclear. Previous experiments in Xenopus laevis embryos demonstrated that antibody-induced disruption of NFs stunts axonal growth but left unresolved how the loss of NFs affects the dynamics of axon growth. In the current study, dissociated cultures were made from the spinal cords of embryos injected at the two-cell stage with an antibody to the middle molecular mass NF protein (NF-M), and time-lapse videomicroscopy was used to study early neurite outgrowth in descendants of both the injected and uninjected blastomeres. The injected antibody altered the growth dynamics primarily in long neurites (>85 microm). These neurites were initiated just as early and terminated growth no sooner than did normal ones. Rather, they spent relatively smaller fractions of time actively extending than normal. When growth occurred, it did so at the same velocity. In very young neurites, which have NFs made exclusively of peripherin, NFs were unaffected, but in the shaft of older neurites, which have NFs that contain NF-M, NFs were disrupted. Thus growth was affected only after NFs were disrupted. In contrast, the distributions of alpha-tubulin and mitochondria were unaffected; thus organelles were still transported into neurites. However, mitochondrial staining was brighter in descendants of injected blastomeres, suggesting a greater demand for energy. Together, these results suggest a model in which intra-axonal NFs facilitate elongation of long axons by making it more efficient.

Advances in neonatal care and surgery.

Neonatology has seen many advances over the past decade. Exogenous surfactant therapy is now a mainstay treatment for respiratory distress syndrome. Partial liquid ventilation, high-frequency ventilation, and inhaled nitric oxide are all relatively new modalities, which have enabled neonatologists to treat with varying degrees of success ever younger and smaller patients. The purpose of this review is to examine studies regarding the long-term outcome of high-risk neonates, the various treatment modalities, and current neonatal surgical techniques, all of which will influence our care of the neonate.

A profile of patients with adhesive capsulitis.

The purpose of this descriptive study is to develop a profile of patients with adhesive capsulitis and to describe the patients' perceived clinical progression. A total of 32 patients diagnosed with adhesive capsulitis and 31 control subject completed anonymous questionnaires designed to elicit demographic data as well as medical information. The adhesive capsulitis and control samples were selected from the same facilities in an effort to reduce bias. Data comparing the adhesive capsulitis group with the control group was analyzed using the Odds Ratio and Taylor Series Confidence Interval for Odds Ratio. Twenty-seven patients (84.4%) diagnosed with adhesive capsulitis fell within the age range of 40-59 years. Diabetes and heart disease appeared to be more prevalent in patients diagnosed with adhesive capsulitis as compared with the control group and general population. The majority of patients with adhesive capsulitis (90.6%) reported a perceived clinical progression that started with a pattern of pain followed by loss of motion. Age and concomitant medical conditions appeared to be most correlated with the occurrence of adhesive capsulitis. Possible reasons for the prevalence of diabetes and heart disease in adhesive capsulitis patients are discussed.

Off-line coupling of capillary electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

An automated fraction collection interface is used in conjunction with matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry to analyze material isolated by capillary electrophoresis (CE). CE fractions are deposited directly on the MALDI probes so that individual peaks from the electropherogram are associated with a single sample spot on the probe. MALDI matrices with high acid concentrations afford enhanced tolerance of electrophoresis buffers. The utility of this hybrid instrument is demonstrated by separation and mass analysis of a tryptic digest of cytochrome c and synthetic mixtures of four proteins. Mass assignments corresponding to the protonated molecular ions are in good agreement with those predicted from molecular structure. Miniaturization of the interface affords enhanced sensitivity, with good-quality spectra from separations of as little as 25 fmol of protein.

Analysis of hydrocarbon dendrimers by laser desorption time-of-flight and fourier transform mass spectrometry.

The first mass spectrometric analysis of a new class of hydrocarbon dendrimers that result from a convergent synthetic approach is reported. Molecular weights of a series of phenylacetylene dendrimers (715 to 14776 u MW) are characterized by ultraviolet matrix-assisted laser desorption (MALDltime-of-flight (TOF) mass spectrometry, direct and silver chemical ionization infrared laser desorption Fourier transform mass spectrometry @I'MSl, and ultraviolet matrix-assisted laser desorption silver chemical ionization Fourier transform mass spectromeby. New matrices and techniques were developed to facilitate analysis of the dendrimers. Mass measurement accuracies between 10 and 25 ppm are obtained for molecular ion species of the five dendrimers analyzed. Laser desorption time-of-flight and FI'MS techniques are shown to be complementary, with FTMS providing high mass resolution (27,000-67,000 resolving power) and accuracy for lower mass dendrimers (10-14 ppm) and MALD TOF yielding the highest resolution (1100 resolving power) and accuracy (25 ppm) for the largest dendrimer. These results are consistent with proposed empirical formulas.

Measurement of erbium confinement in optical fibers: a differential mode-launching technique.

We present a selective mode-launching technique to determine the confinement of erbium in optical fibers. The loss per meter, alpha(lm), of the individual LP(lm) modes (LP(01) and LP(11) at 980 nm) is measured, and the ratio gamma = alpha(01)/alpha(11) is related to the concentration of erbium in the core. We assume a Gaussian diffusion profile for erbium and relate the dependence of gamma on erbium confinement by using exact mode profiles. This technique uses only two sets of measurements and is independent of erbium concentration.

Bath osmolality: effect on water permeability of epithelial tissue.

When hyperosmotic gradients from 100 to 500 mosM are used to produce a water flux, the water permeability of live and potassium cyanide (KCN)-poisoned frog skin decreases with increasing osmotic gradients. In addition, as the total bath osmolality (corium + epithelial) increases there is a reduction in tissue water. Examination of the tissue cellular and extracellular compartments shows that cell shrinkage caused by the increasing hyperosmolality of the bathing medium correlates with the decrease in osmotic permeability. When the bath osmolality is held constant and cell volume decreases, there is a decrease in the water permeability. High potassium in the external bathing medium causes cell swelling that is associated with an increase in water permeability. These data support the hypothesis that a number of conditions known to affect the water permeability of frog skin do so partly or wholly as a result of a change in the cell volume, which either directly or indirectly alters the osmotic permeability of a rate limiting barrier, possibly the cell membrane.