Long Electrical Stability on Dual Acceptor p-Type ZnO:Ag,N Thin Films.

p-type Ag-N dual acceptor doped ZnO thin films with long electrical stability were deposited by DC magnetron reactive co-sputtering technique. After deposition, the films were annealed at 400 °C for one hour in a nitrogen-controlled atmosphere. The deposited films were amorphous. However, after annealing, they crystallize in the typical hexagonal wurtzite structure of ZnO. The Ag-N dual acceptors were incorporated substitutionally in the structure of zinc oxide, and achieving that; the three samples presented the p-type conductivity in the ZnO. Initial electrical properties showed a low resistivity of from 1 to 10-3 Ω·cm, Hall mobility of tens cm2/V·s, and a hole concentration from 1017 to 1019 cm-3. The electrical stability analysis reveals that the p-type conductivity of the ZnO:Ag,N films is very stable and does not revert to n-type, even after 36 months of aging. These results reveal the feasibility of using these films for applications in short-wavelength or transparent optoelectronic devices.

Physicochemical characterization of cape gooseberry (Physalis peruviana L.) fruits ecotype Colombia during preharvest development and growth.

Cape gooseberry fruits are increasingly recognized due to their excellent organoleptic and functional characteristics as a food. As the cultivation of this fruit expands, it is necessary to determine the quality characteristics and evolution of the new growing zones. This study sought to characterize the growth and development of cape gooseberry fruits, Ecotype Colombia, in the Ventaquemada region (Department of Boyacá in Colombia). For the experiments, 50 plants were taken completely at random from which 20 flowers of the middle third were selected and marked considering that 50% of the flowers were open. The selected cape gooseberry plants were 9 months old from the establishment. Samples were carried out every 5-7 days to evaluate changes in different physiological and physicochemical properties of the fruits such as equatorial diameter, weight, dry matter, respiration intensity (RI), total soluble solids (SST), titratable acidity (TA), and maturity ratio (SST/TA). Logistic and modified enzyme kinetics models were fitted to represent the change in these characteristics as a function of growth time and to establish a suitable maturity index. A rapid increase in the growth and a substantive change in the properties of the fruits were observed between 36 and 45 days after anthesis (DAA) and stabilization between 60 and 65 DAA, which constitutes the stage of physiological maturity. At this stage, fruits with a polar/equatorial diameter of 2.2-2.5 cm, 14.9% TSS, 2.2% TA, and 191.7 cm3 CO2 /g/d RI were obtained. Likewise, from the adjusted models, it was possible to identify these changes, especially for the relative growth rate (RGR), color index, and maturity ratio. PRACTICAL APPLICATION: In this work, we present the characterization of some physicochemical properties of cape gooseberry throughout its development and preharvest growth. This fruit is of wide interest due to its broad nutritional properties and is known as a "superfruit." The monitoring of the changes in the quality characteristics is important because it allows producers to define an optimum maturity stage for its commercialization. We also fit suitable regression models to relate the evolution in the product as a function of time and provide prediction tools to monitor fruit development. The above can help growers better schedule their production cycles.

Chitosan-G-Glycidyl Methacrylate/Au Nanocomposites Promote Accelerated Skin Wound Healing.

Herein, we report the synthesis of Au nanoparticles (AuNPs) in chitosan (CTS) solution by chemically reducing HAuCl4. CTS was further functionalized with glycidyl methacrylate (chitosan-g-glycidyl methacrylate/AuNP, CTS-g-GMA/AuNP) to improve the mechanical properties for cellular regeneration requirements of CTS-g-GMA/AuNP. Our nanocomposites promote excellent cellular viability and have a positive effect on cytokine regulation in the inflammatory and anti-inflammatory response of skin cells. After 40 days of nanocomposite exposure to a skin wound, we showed that our films have a greater skin wound healing capacity than a commercial film (TheraForm®), and the presence of the collagen allows better cosmetic ave aspects in skin regeneration in comparison with a nanocomposite with an absence of this protein. Electrical percolation phenomena in such nanocomposites were used as guiding tools for the best nanocomposite performance. Our results suggest that chitosan-based Au nanocomposites show great potential for skin wound repair.

Rates of Cesarean Conversion and Associated Predictors and Outcomes in Planned Vaginal Twin Deliveries.

OBJECTIVE: Twin vaginal deliveries (VDs) are often performed in the operating room (OR) given the risk of conversion to cesarean delivery (CD) for the aftercoming twin. We aim to investigate the rates of conversion to CD for planned twin VDs and identify predictors and outcomes of conversion. STUDY DESIGN: A retrospective cohort study of all women who underwent a planned twin VD at two large academic medical centers over 4 years. Demographic and outcome data were chart abstracted. Various statistical tests were used to evaluate the influence of perinatal variables on mode of delivery and identify possible predictors of conversion. RESULTS: Eight hundred and eighty-five twin deliveries were identified, of which 725 (81.9%) were possible candidates for VD. Of those, 237 (32.7%) underwent successful VD of twin A. Ninety-five (40.1%) had a nonvertex second twin at time of delivery. Conversion to CD occurred in 10 planned VDs (4.2%). Conversions were higher with spontaneous labor (relative risk [RR]: 2.1; 95% confidence interval [CI] 1.6-2.7; p = 0.003), and having an intertwin delivery interval greater than 60 minutes (RR: 5.1; 95% CI: 2.5-10.8; p < 0.001). Nonvertex presentation of twin B, type of delivery provider, or years out in practice of delivery provider were not significantly different between groups. There were no significant differences in neonatal outcomes between VD and conversion groups. There was a significant association between use of forceps for twin B and successful VD (p = 0.02), with 84.6% in the setting of a nonvertex twin B. CONCLUSION: Successful VD was achieved in planned VD of twins in 95.8% of cases, and there were no significant differences in maternal and fetal outcomes between successful VD and conversion to CD for twin B. With the optimal clinical scenario and shared decision-making, performing vaginal twin deliveries in labor and delivery rooms should be discussed. KEY POINTS: · There is a propensity to perform twin vaginal deliveries in the operating room.. · Rates of conversion to cesarean section are very low.. · There are no significant differences in perinatal outcomes with conversion..

Methylation-Sensitive Loop-Mediated Isothermal Amplification (LAMP): Nucleic Acid Methylation Detection through LAMP with Mobile Fluorescence Readout.

The emergence of epigenetic gene regulation and its role in disease have motivated a growing field of epigenetic diagnostics for risk assessment and screening. In particular, irregular cytosine DNA base methylation has been implicated in several diseases, yet the methods for detecting these epigenetic marks are limited to lengthy protocols requiring bulky and costly equipment. We demonstrate a simple workflow for detecting methylated CpG dinucleotides in synthetic and genomic DNA samples using methylation-sensitive restriction enzyme digestion followed by loop-mediated isothermal amplification. We additionally demonstrate a cost-effective mobile fluorescence reader comprising a light-emitting diode bundle, a mirror, and optical fibers to transduce fluorescence signals associated with DNA amplification. The workflow can be performed in approximately 1 h, requiring only a simple heat source, and can therefore provide a foundation for distributable point-of-care testing of DNA methylation levels.

Magnetic microparticle concentration and collection using a mechatronic magnetic ratcheting system.

Magnetic ratcheting cytometry is a promising approach to separate magnetically-labeled cells and magnetic particles based on the quantity of magnetic material. We have previously reported on the ability of this technique to separate magnetically-labeled cells. Here, with a new chip design, containing high aspect ratio permalloy micropillar arrays, we demonstrate the ability of this technique to rapidly concentrate and collect superparamagnetic iron oxide particles. The platform consists of a mechatronic wheel used to generate and control a cycling external magnetic field that impinges on a "ratcheting chip." The ratcheting chip is created by electroplating a 2D array of high aspect ratio permalloy micropillars onto a glass slide, which is embedded in a thin polymer layer to create a planar surface above the micropillars. By varying magnetic field frequency and direction through wheel rotation rate and angle, we direct particle movement on chip. We explore the operating conditions for this system, identifying the effects of varying ratcheting frequency, along with time, on the dynamics and resulting concentration of these magnetic particles. We also demonstrate the ability of the system to rapidly direct the movement of superparamagnetic iron oxide particles of varying sizes. Using this technique, 2.8 µm, 500 nm, and 100 nm diameter superparamagnetic iron oxide particles, suspended within an aqueous fluid, were concentrated. We further define the ability of the system to concentrate 2.8 µm superparamagnetic iron oxide particles, present in a liquid suspension, into a small chip surface area footprint, achieving a 100-fold surface area concentration, and achieving a concentration factor greater than 200%. The achieved concentration factor of greater than 200% could be greatly increased by reducing the amount of liquid extracted at the chip outlet, which would increase the ability of achieving highly sensitive downstream analytical techniques. Magnetic ratcheting-based enrichment may be useful in isolating and concentrating subsets of magnetically-labeled cells for diagnostic automation.

A comparison of microfluidic methods for high-throughput cell deformability measurements.

The mechanical phenotype of a cell is an inherent biophysical marker of its state and function, with many applications in basic and applied biological research. Microfluidics-based methods have enabled single-cell mechanophenotyping at throughputs comparable to those of flow cytometry. Here, we present a standardized cross-laboratory study comparing three microfluidics-based approaches for measuring cell mechanical phenotype: constriction-based deformability cytometry (cDC), shear flow deformability cytometry (sDC) and extensional flow deformability cytometry (xDC). All three methods detect cell deformability changes induced by exposure to altered osmolarity. However, a dose-dependent deformability increase upon latrunculin B-induced actin disassembly was detected only with cDC and sDC, which suggests that when exposing cells to the higher strain rate imposed by xDC, cellular components other than the actin cytoskeleton dominate the response. The direct comparison presented here furthers our understanding of the applicability of the different deformability cytometry methods and provides context for the interpretation of deformability measurements performed using different platforms.

Fractal LAMP: Label-Free Analysis of Fractal Precipitate for Digital Loop-Mediated Isothermal Nucleic Acid Amplification.

Nucleic acid amplification assays including loop-mediated isothermal amplification (LAMP) are routinely used in diagnosing diseases and monitoring water and food quality. The results of amplification in these assays are commonly measured with an analog fluorescence readout, which requires specialized optical equipment and can lack quantitative precision. Digital analysis of amplification in small fluid compartments based on exceeding a threshold fluorescence level can enhance the quantitative precision of nucleic acid assays (i.e., digital nucleic acid amplification assays), but still requires specialized optical systems for fluorescence readout and the inclusion of a fluorescent dye. Here, we report Fractal LAMP, an automated method to detect amplified DNA in subnanoliter scale droplets following LAMP in a label-free manner. Our computer vision algorithm achieves high accuracy detecting DNA amplification in droplets by identifying LAMP byproducts that form fractal structures observable in brightfield microscopy. The capabilities of Fractal LAMP are further realized by developing a Bayesian model to estimate DNA concentrations for unknown samples and a bootstrapping method to estimate the number of droplets required to achieve target limits of detection. This digital, label-free assay has the potential to lower reagent and reader cost for nucleic acid measurement while maintaining high quantitative accuracy over 3 orders of magnitude of concentration.

Effects of Flow-Induced Microfluidic Chip Wall Deformation on Imaging Flow Cytometry.

Imaging flow cytometry is a powerful tool by virtue of its capability for high-throughput cell analysis. The advent of high-speed optical imaging methods on a microfluidic platform has significantly improved cell throughput and brought many degrees of freedom to instrumentation and applications over the last decade, but it also poses a predicament on microfluidic chips. Specifically, as the throughput increases, the flow speed also increases (currently reaching 10 m/s): consequently, the increased hydrodynamic pressure on the microfluidic chip deforms the wall of the microchannel and produces detrimental effects lead to defocused and blur image. Here, we present a comprehensive study of the effects of flow-induced microfluidic chip wall deformation on imaging flow cytometry. We fabricated three types of microfluidic chips with the same geometry and different degrees of stiffness made of polydimethylsiloxane (PDMS) and glass to investigate material influence on image quality. First, we found the maximum deformation of a PDMS microchannel was >60 µm at a pressure of 0.6 MPa, while no appreciable deformation was identified in a glass microchannel at the same pressure. Second, we found the deviation of lag time that indicating velocity difference of migrating microbeads due to the deformation of the microchannel was 29.3 ms in a PDMS microchannel and 14.9 ms in a glass microchannel. Third, the glass microchannel focused cells into a slightly narrower stream in the X-Y plane and a significantly narrower stream in the Z-axis direction (focusing percentages were increased 30%, 32%, and 5.7% in the glass channel at flow velocities of 0.5, 1.5, and 3 m/s, respectively), and the glass microchannel showed stabler equilibrium positions of focused cells regardless of flow velocity. Finally, we achieved the world's fastest imaging flow cytometry by combining a glass microfluidic device with an optofluidic time-stretch microscopy imaging technique at a flow velocity of 25 m/s. © 2019 International Society for Advancement of Cytometry.

Zollinger-ellison syndrome. case report

ABSTRACT Introduction: The Zollinger-Ellison syndrome (ZES) is a pathology caused by a neuroendocrine tumor, usually located in the pancreas or the duodenum, which is characterized by elevated levels of gastrin, resulting in an excessive production of gastric acid. Case presentation: A 42-year-old female patient with a history of longstanding peptic ulcer disease, who consulted due to persistent epigastric pain, melena and signs of peritoneal irritation. Perforated peptic ulcer was suspected, requiring emergency surgical intervention. Subsequently, a tumor lesion in the head of the pancreas was documented and managed with Whipple procedure. The pathology results reported a tumor suggestive of neuroendocrine neoplasm. Discussion: The Zollinger-Ellison syndrome occurs in 0.1 to 3 people per 1 000 000 inhabitants worldwide and is predominant in women between 20 and 50 years of age. It usually appears as a refractory acid-peptic disease or as a complication of gastric acid hypersecretion. Medical therapy is the standard management, being proton pump inhibitors (PPI) the most effective option. Surgery is recommended for sporadic ZES. Conclusions: ZES has a low incidence rate. It is rarely considered in the differential diagnosis of chronic epigastric pain and high clinical suspicion is required to achieve adequate management. This article is highly relevant as it presents a confirmed clinical case of ZES in Colombia, highlighting the importance of producing local scientific literature to improve the diagnosis and treatment of this pathology.

RESUMEN Introducción. El síndrome de Zollinger-Ellison (SZE) es una patología producida por un tumor neuroendocrino habitualmente localizado a nivel duodenal o pancreático, el cual produce niveles elevados de gastrina, derivando en hipersecreción de ácido gástrico. Presentación del caso. Paciente femenino de 42 años con antecedente de enfermedad ulceropéptica de larga data, quién consulta por epigastralgia persistente y deposiciones melénicas y presenta signos de irritación peritoneal. Se sospecha una ulcera péptica perforada, requiriendo intervención quirúrgica de urgencia. Posteriormente se documenta una lesión tumoral en la cabeza del páncreas, manejada con cirugía de Whipple; en el reporte de patología se detecta un tumor sugestivo de neoplasia neuroendocrina. Discusión. El SZE se presenta en 0.1-3 personas por cada 1 000 000 de habitantes a nivel mundial, predominantemente en mujeres entre 20 y 50 años de edad. Suele debutar como enfermedad ácido-péptica refractaria o por complicaciones de la hipersecreción gástrica. La terapia médica es el manejo estándar, siendo la más efectiva la que involucra inhibidores de la bomba de protones. En SZE esporádico está recomendada la cirugía. Conclusiones. El SZE tiene una incidencia baja, raramente se considera en el diagnóstico diferencial de epigastralgia crónica y se requiere alta sospecha clínica para lograr un manejo adecuado. Este artículo es valioso al presentar un caso clínico confirmado de SZE en Colombia, destacando la importancia de producir bibliografía científica local para mejorar el diagnóstico y tratamiento de esta patología.

Guidelines for synoptic reporting of surgery and pathology in Hirschsprung disease.

BACKGROUND/PURPOSE: Synoptic, or standardized, reporting of surgery and pathology reports has been widely adopted in surgical oncology. Patients with Hirschsprung disease may experience morbidity related to surgical factors or underlying pathology and often undergo multiple operations. Our aim is to improve the postoperative outcome and care of patients with Hirschsprung disease by proposing a standardized set of data that should be included in every surgery and pathology report. METHODS: Members of the American Pediatric Surgical Association Hirschsprung Disease Interest Group and experts in pediatric pathology of Hirschsprung disease participated in group discussions, performed literature review and arrived at expert consensus guidelines for surgery and pathology reporting. RESULTS: The importance of accurate operative and pathologic reports and the implications of inadequate documentation in patients with Hirschsprung disease are discussed and guidelines for standardizing these reports are provided. CONCLUSIONS: Adherence to the principles of reporting for operations and surgical pathology may improve outcomes for Hirschsprung disease patients and will facilitate identification of correlations among morphology, function, genetics and outcomes, which are required to improve the overall management of these patients. LEVEL OF EVIDENCE: V.

Single-Cell Analysis of Morphological and Metabolic Heterogeneity in Euglena gracilis by Fluorescence-Imaging Flow Cytometry.

Microalgal biofuels and biomass have ecofriendly advantages as feedstocks. Improved understanding and utilization of microalgae require large-scale analysis of the morphological and metabolic heterogeneity within populations. Here, with Euglena gracilis as a model microalgal species, we evaluate how fluorescence- and brightfield-derived-image-based descriptors vary during environmental stress at the single-cell level. This is achieved with a new multiparameter fluorescence-imaging cytometric technique that allows the assaying of thousands of cells per experiment. We track morphological changes, including the intensity and distribution of intracellular lipid droplets, and pigment autofluorescence. The combined fluorescence-morphological analysis identifies new metrics not accessible with traditional flow cytometry, including the lipid-to-cell-area ratio (LCAR), which shows promise as an indicator of oil productivity per biomass. Single-cell metrics of lipid productivity were highly correlated ( R2 > 0.90, p < 0.005) with bulk oil extraction. Such chemomorphological atlases of algal species can help optimize growth conditions and selection approaches for large-scale biomass production.

Obesity increases airway smooth muscle responses to contractile agonists.

The asthma-obesity syndrome represents a major public health concern that disproportionately contributes to asthma severity and induces insensitivity to therapy. To date, no study has shown an intrinsic difference between human airway smooth muscle (HASM) cells derived from nonobese subjects and those derived from obese subjects. The objective of this study was to address whether there is a greater response to agonist-induced calcium mobilization, phosphorylation of myosin light chain (MLC), and greater shortening in HASM cells derived from obese subjects. HASM cells derived from nonobese and obese subjects were age and sex matched. Phosphorylation of MLC was measured after having been stimulated by carbachol. Carbachol- or histamine-induced mobilization of calcium and cell shortening were assessed in HASM cells derived from nonobese and obese donors. Agonist-induced MLC phosphorylation, mobilization of calcium, and cell shortening were greater in obese compared with non-obese-derived HASM cells. The MLC response was comparable in HASM cells derived from obese nonasthma and nonobese fatal asthma subjects. HASM cells derived from obese female subjects were more responsive to carbachol than HASM cells derived from obese male subjects. Insulin pretreatment had little effect on these responses. Our results show an increase in agonist-induced calcium mobilization associated with an increase in MLC phosphorylation and an increase in ASM cell shortening in favor of agonist-induced hyperresponsiveness in HASM cells derived from obese subjects. Our studies suggest that obesity induces a retained phenotype of hyperresponsiveness in cultured human airway smooth muscle cells.

High-power widely tunable ps source in the visible light based on four wave mixing in optimized photonic crystal fibers.

We present a detailed study on the generation of widely tunable visible light through four wave mixing in specifically designed micro-structured fibers. The fiber's properties are optimized for an efficient conversion to the visible and near infrared with a combined tunability from 620 to 910 nm of a picosecond Yb-doped tunable source for biomedical applications.

Shape-based separation of microalga Euglena gracilis using inertial microfluidics.

Euglena gracilis (E. gracilis) has been proposed as one of the most attractive microalgae species for biodiesel and biomass production, which exhibits a number of shapes, such as spherical, spindle-shaped, and elongated. Shape is an important biomarker for E. gracilis, serving as an indicator of biological clock status, photosynthetic and respiratory capacity, cell-cycle phase, and environmental condition. The ability to prepare E. gracilis of uniform shape at high purities has significant implications for various applications in biological research and industrial processes. Here, we adopt a label-free, high-throughput, and continuous technique utilizing inertial microfluidics to separate E. gracilis by a key shape parameter-cell aspect ratio (AR). The microfluidic device consists of a straight rectangular microchannel, a gradually expanding region, and five outlets with fluidic resistors, allowing for inertial focusing and ordering, enhancement of the differences in cell lateral positions, and accurate separation, respectively. By making use of the shape-activated differences in lateral inertial focusing dynamic equilibrium positions, E. gracilis with different ARs ranging from 1 to 7 are directed to different outlets.

Anoftalmia congénita. Reporte de una serie familiar / Congenital anophthalmia. Report of a family series

Anoftalmia es la ausencia de un ojo, puede ser unilateral o bilateral y su prevalencia es baja. Resulta de la detención del desarrollo del globo ocular durante la organogénesis. Pacientes de 25, 23 y 22 años, hermanas, presentan anoftalmia congénita unilateral derecha, bilateral y unilateral izquierda respectivamente. Único antecedente mórbido familiar es que su bisabuelo paterno también padecía anoftalmia congénita unilateral derecha. Fueron remitidas desde el Hospital Clínico Regional a la Clínica de Traumatología y Prótesis Máxilo Facial de la Universidad de Concepción para tratarlas desde sus primeros meses de vida. El tratamiento incluyó el uso de conformadores secuenciales para expandir las cavidades oculares y posteriormente se confeccionaron prótesis oculares individuales. La rehabilitación de la anoftalmia congénita es todo un desafío. La intervención temprana, como lo fue el caso de estas pacientes, hace una gran diferencia en el desarrollo general del paciente y el bienestar emocional de la familia

Anophthalmia is the absence of an eye. This may be unilateral or bilateral and its prevalence is low. It results from developmental arrest of the globe during organogenesis. Three patients aged 22, 23 and 25, sisters, have congenital unilateral right-sided, bilateral and unilateral left-sided anophthalmia respectively. The only family history element is that their paternal great-grandfather also suffered from congenital unilateral right-sided anophthalmia. They were sent from the Regional Clinical Hospital to the Clinic of Trauma and Maxillofacial Prosthetics at Universidad de Concepción to be treated from their first months of life. The treatment included the use of sequential conformers to expand the eye sockets, and then individual ocular prostheses were prepared and installed. The rehabilitation of congenital anophthalmia is a major challenge. Early intervention, as was the case with these patients, makes a significant difference on the overall development of the patient and on the emotional well-being of the family

Automated Detection, Localization, and Classification of Traumatic Vertebral Body Fractures in the Thoracic and Lumbar Spine at CT.

PURPOSE: To design and validate a fully automated computer system for the detection and anatomic localization of traumatic thoracic and lumbar vertebral body fractures at computed tomography (CT). MATERIALS AND METHODS: This retrospective study was HIPAA compliant. Institutional review board approval was obtained, and informed consent was waived. CT examinations in 104 patients (mean age, 34.4 years; range, 14-88 years; 32 women, 72 men), consisting of 94 examinations with positive findings for fractures (59 with vertebral body fractures) and 10 control examinations (without vertebral fractures), were performed. There were 141 thoracic and lumbar vertebral body fractures in the case set. The locations of fractures were marked and classified by a radiologist according to Denis column involvement. The CT data set was divided into training and testing subsets (37 and 67 subsets, respectively) for analysis by means of prototype software for fully automated spinal segmentation and fracture detection. Free-response receiver operating characteristic analysis was performed. RESULTS: Training set sensitivity for detection and localization of fractures within each vertebra was 0.82 (28 of 34 findings; 95% confidence interval [CI]: 0.68, 0.90), with a false-positive rate of 2.5 findings per patient. The sensitivity for fracture localization to the correct vertebra was 0.88 (23 of 26 findings; 95% CI: 0.72, 0.96), with a false-positive rate of 1.3. Testing set sensitivity for the detection and localization of fractures within each vertebra was 0.81 (87 of 107 findings; 95% CI: 0.75, 0.87), with a false-positive rate of 2.7. The sensitivity for fracture localization to the correct vertebra was 0.92 (55 of 60 findings; 95% CI: 0.79, 0.94), with a false-positive rate of 1.6. The most common cause of false-positive findings was nutrient foramina (106 of 272 findings [39%]). CONCLUSION: The fully automated computer system detects and anatomically localizes vertebral body fractures in the thoracic and lumbar spine on CT images with a high sensitivity and a low false-positive rate.

Advances in the production and handling of encoded microparticles.

Here we highlight emerging technologies in the synthesis, handling, and application of encoded microparticles for multiplexed assays. Traditionally, in drug discovery and life sciences research, multiple reactions will be conducted in parallel using microwell plate formats or microfluidic implementations, in which volumes are confined and reactions annotated by knowledge of what reagents were added to each volume. Microparticle-based information carriers provide an alternative approach to performing such multiplexed reactions, in which reactions and events are instead annotated with unique codes associated with the solid-phase particle. One challenge has been in creating a unique and large enough code set that is also easily readout, and we highlight two approaches that have brought orthogonal optical tagging techniques to bear. Another challenge has been that in such approaches, reactions have usually been confined to the surface of, or within the bulk of the specifically-tagged particle. We also highlight a creative approach and strategy for multiplexing - called "partipetting"- in which the coded particle can be a carrier of a unique fluid reagent.

Cortical shell unwrapping for vertebral body abnormality detection on computed tomography.

The vertebral body is the main axial load-bearing structure of the spinal vertebra. Assessment of acute injury and chronic deformity of the vertebral body is difficult to assess accurately and quantitatively by simple visual inspection. We propose a cortical shell unwrapping method to examine the vertebral body for injury such as fractures and degenerative osteophytes. The spine is first segmented and partitioned into vertebrae. Then the cortical shell of the vertebral body is extracted using deformable dual-surface models. The cortical shell is then unwrapped onto a 2D map and the complex 3D detection problem is effectively converted to a pattern recognition problem on a 2D plane. Characteristic features adapted for different applications are computed and sent to a committee of support vector machines for classification. The system was evaluated on two applications, one for fracture detection on trauma CT datasets and the other on degenerative osteophyte assessment on sodium fluoride PET/CT. The fracture CAD achieved 93.6% sensitivity at 3.2 false positive per patient and the degenerative osteophyte CAD achieved 82% sensitivity at 4.7 false positive per patient.

High Throughput Screen Identifies Natural Product Inhibitor of Phenylalanyl-tRNA Synthetase from Pseudomonas aeruginosa and Streptococcus pneumoniae.

Pseudomonas aeruginosa and Streptococcus pneumoniae are causative agents in a wide range of infections. Genes encoding proteins corresponding to phenylalanyl-tRNA synthetase (PheRS) were cloned from both bacteria. The two forms of PheRS were kinetically evaluated and the K(m)'s for P. aeruginosa PheRS with its three substrates, phenylalanine, ATP and tRNA(Phe) were determined to be 48, 200, and 1.2 µM, respectively, while the K(m)'s for S. pneumoniae PheRS with respect to phenylalanine, ATP and tRNA(Phe) were 21, 225 and 0.94 µM, respectively. P. aeruginosa and S. pneumoniae PheRS were used to screen a natural compound library and a single compound was identified that inhibited the function of both enzymes. The compound inhibited P. aeruginosa and S. pneumoniae PheRS with IC50's of 2.3 and 4.9 µM, respectively. The compound had a K(I) of 0.83 and 0.98 µM against P. aeruginosa and S. pneumoniae PheRS, respectively. The minimum inhibitory concentration (MIC) of the compound was determined against a panel of Gram positive and negative bacteria including efflux pump mutants and hyper-sensitive strains. MICs against wild-type P. aeruginosa and S. pneumoniae cells in culture were determined to be 16 and 32 µg/ml, respectively. The mechanism of action of the compound was determined to be competitive with the amino acid, phenylalanine, and uncompetitive with ATP. There was no inhibition of cytoplasmic protein synthesis, however, partial inhibition of the human mitochondrial PheRS was observed.