Comparison of two serological screening strategies for cytomegalovirus primary infection in the first trimester of pregnancy.

INTRODUCTION: CMV serology screening in the first trimester pregnancy is based on IgG and IgM testing followed by IgG avidity in cases with positive IgM. However, the sensitivity of this strategy to diagnose maternal primary infection has been questioned. The objective of the study was to compare this strategy 1 with a strategy 2 consisting of running avidity test on all samples with positive IgG (ignoring IgM results) using fully automated current generation CMV IgG, IgM and IgG avidity assays. POPULATION AND METHODS: 1516 consecutive pregnant women between 12 and 14 weeks were screened in one maternity. Strategy 1 was done prospectively with LIAISON® CMV IgG II and LIAISON® CMV IgM II, followed by LIAISON® CMV IgG Avidity II and VIDAS® CMV IgG avidity II testing in cases with positive or equivocal IgM. Strategy 2 was done retrospectively on the same population and consisted of running avidity with the LIAISON® CMV IgG Avidity II in all samples with positive IgG. RESULTS: The sensitivity to diagnose a confirmed or a possible maternal primary infection in the first trimester was 91.6 % and 83 % for strategy 1 and 2 respectively (p > 0.99). Strategy 1 missed one possible primary infection and strategy 2 missed 2 confirmed primary infection. Inconclusive results happened in 0 and 0.7 % of samples with strategy 1 and 2 respectively. CONCLUSION: This study suggests that strategy 1 has better sensitivity and practicability than strategy 2. However, to achieve a good performance with strategy 1, using highly sensitive IgM assay is mandatory.

Tactile imaging of an imbedded palpable structure for breast cancer screening.

Apart from texture, the human finger can sense palpation. The detection of an imbedded structure is a fine balance between the relative stiffness of the matrix, the object, and the device. If the device is too soft, its high responsiveness will limit the depth to which the imbedded structure can be detected. The sensation of palpation is an effective procedure for a physician to examine irregularities. In a clinical breast examination (CBE), by pressing over 1 cm(2) area, at a contact pressure in the 70-90 kPa range, the physician feels cancerous lumps that are 8- to 18-fold stiffer than surrounding tissue. Early detection of a lump in the 5-10 mm range leads to an excellent prognosis. We describe a thin-film tactile device that emulates human touch to quantify CBE by imaging the size and shape of 5-10 mm objects at 20 mm depth in a breast model using ∼80 kPa pressure. The linear response of the device allows quantification where the greyscale corresponds to the relative local stiffness. The (background) signal from <2.5-fold stiffer objects at a size below 2 mm is minimal.

Imaging electroluminescence from individual nanoparticles in an array exhibiting room temperature single electron effect.

Electroluminescence (EL) from the monolayer of a network of a one-dimensional (1D) necklace of 10 nm Au particles (nano)cemented by CdS is imaged. The EL and photoluminescence (PL) spectra confirm the emission from CdS. The EL emission blinks and is highly specular. The position of the speckles from individual CdS cement sites is independent of magnitude and polarity of the applied bias. The EL is explained by field-assisted ionization of the cement due to high internal fields in the array caused by stationary local charging that also leads to robust single electron effect at room temperature.

Ultrasoft 100 nm thick zero Poisson's ratio film with 60% reversible compressibility.

About a 100 nm thick multilayer film of nanoparticle monolayers and polymer layers is shown to behave like cellular-foam with a modulus below 100 KPa. The 1.25 cm radius film adhered to a rigid surface can be compressed reversibly to 60% strain. The more than 4 orders of magnitude lower modulus compared to its constituents is explained by considering local bending in the (nano)cellular structure, similar to cork and wings of beetles. As the rigidity of the polymer backbone is increased in just four monolayers, the modulus of the composite increases by over 70%. Electro-optical map of the strain distribution over the area of compression and increase in modulus with thickness indicates the films have zero Poisson's ratio.