Time reversal microwave breast imaging for contrast-enhanced tumor classification

This paper studies the decomposition of the time reversal operator (DORT, by the French acronym) technique for microwave breast lesion classification. We apply the finitedifference time-domain (FDTD) method to a realistic numerical breast phantom where lesion-like targets are artificially introduced, and obtain the multistatic data matrix (MDM) for a particular antenna array configuration. Then, the singular value decomposition (SVD) of this matrix is derived for different targets, which represent malignant and benign lesions. We show that the singular value spectrum can assist in classifying these targets as malignant or benign, especially in the case where contrast-enhanced agents can be employed to allow the analysis of differential backscatter data.

Dijet azimuthal decorrelations in pp collisions at √s=7 TeV

Measurements of dijet azimuthal decorrelations in pp collisions at √s=7 TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding to an integrated luminosity of 2.9 pb⁻¹. The results are compared to predictions from perturbative QCD calculations and various Monte Carlo event generators. The dijet azimuthal distributions are found to be sensitive to initial-state gluon radiation.

Alterations in the proteome of the NHERF2 knockout mouse jejunal brush border membrane vesicles

To identify additional potential functions for the multi-PDZ domain containing protein Na+/H+ exchanger regulatory factor 2 (NHERF2), which is present in the apical domain of intestinal epithelial cells, proteomic studies of mouse jejunal villus epithelial cell brush border membrane vesicles compared wild-type to homozygous NHERF2 knockout FVB mice by a two-dimensional liquid chromatography-tandem mass spectrometry (LC-MS/MS)-iTRAQ approach. Jejunal architecture appeared normal in NHERF2 null in terms of villus length and crypt depth, Paneth cell number, and microvillus structure by electron microscopy. There was also no change in proliferative activity based on BrdU labeling. Four brush border membrane vesicles (BBMV) preparations from wild-type mouse jejunum were compared with four preparations from NHERF2 knockout mice. LC-MS/MS identified 450 proteins in both matched wild-type and NHERF2 null BBMV; 13 proteins were changed in two or more separate BBMV preparations (9 increased and 4 decreased in NHERF2 null mice), while an additional 92 proteins were changed in a single BBMV preparation (68 increased and 24 decreased in NHERF2 null mice). These proteins were categorized as 1) transport proteins (one increased and two decreased in NHERF2 null); 2) signaling molecules (2 increased in NHERF2 null); 3) cytoskeleton/junctional proteins (4 upregulated and 1 downregulated in NHERF2 null); and 4) metabolic proteins/intrinsic BB proteins) (2 upregulated and 1 downregulated in NHERF2 null). Immunoblotting of BBMV was used to validate or extend the findings, demonstrating increase in BBMV of NHERF2 null of MCT1, coronin 3, and ezrin. The proteome of the NHERF2 null mouse small intestinal BB demonstrates up- and downregulation of multiple transport proteins, signaling molecules, cytoskeletal proteins, tight junctional and adherens junction proteins, and proteins involved in metabolism, suggesting involvement of NHERF2 in multiple apical regulatory processes and interactions with luminal contents.

The expression of Sirtuins 1 and 4 in peripheral blood leukocytes from patients with type 2 diabetes

This study was designed to investigate the relationship between SIRTs 1 and 4 in peripheral blood leukocytes (PBLs) and human type 2 diabetes mellitus (T2DM). SIRTs 1 and 4 have been confirmed to be associated with homeostasis of glucose/lipid metabolism, but their roles in T2DM are still poorly understood. Peripheral blood and biochemical data were collected from 52 healthy individuals (normal control group, NC group) and 113 cases of T2DM patients. Immunocytochemical staining was used to detect SIRT1 and SIRT4 and reverse transcription polymerase chain reaction (RT-PCR) was used to detect SIRT1 or SIRT4 mRNA levels in PBLs. Immunocytochemical staining showed that SIRT1 is expressed in both nucleus and cytoplasm, and SIRT4 in the cytoplasm of granulocytes and monocytes. No SIRT1 or SIRT4 was found in lymphocytes. RT-PCR showed that SIRT1 and SIRT4 mRNA levels in T2DM group were lower than those in NC group (P<0.01). Correlation analysis showed that there is a negative correlation between SIRTs 1 and 4 and fasting plasma glucose (FPG) (P<0.05) (r= -0.161 and -0.156), a positive correlation between SIRT4 mRNA levels and triglyceride (TG)/lipoprotein a (LPa) levels (P<0.05), and a negative correlation between SIRT4 mRNA levels and high density lipoprotein cholesterol (HDL) (P<0.05). SIRTs 1 and 4 may have a role in the pathogenesis of T2DM and their expression in granulocytes and monocytes may indirectly reflect the homeostasis of glucose/lipid metabolism in T2DM.

Measurement of the B(+) production cross section in pp collisions at sqrt[s]=7 TeV

Measurements of the total and differential cross sections dσ/dp(T)(B) and dσ/dy(B) for B(+) mesons produced in pp collisions at sqrt[s]=7  TeV are presented. The data correspond to an integrated luminosity of 5.8  pb(-1) collected by the CMS experiment operating at the LHC. The exclusive decay B(+)→J/ψK(+), with J/ψ→μ(+)μ(-), is used to detect B(+) mesons and to measure the production cross section as a function of p(T)(B) and y(B). The total cross section for p(T)(B)>5  GeV and |y(B)|<2.4 is measured to be 28.1±2.4±2.0±3.1  μb, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement.

3D deconvolution of spherically aberrated images using commercial software

Refractive index mismatch between the specimen and the objective immersion oil results in spherical aberration, which causes distortion and spreading of the point spread function, as well as incorrect readings of the axial coordinates. These effects have to be taken into account when performing three-dimensional restoration of wide-field fluorescence images. By using objects with well-defined geometry (fluorescently stained Escherichia coli or actin filaments) separated from a cover slip by a layer of oil with known refractive index, we investigated the accuracy of three-dimensional shape restoration by the commercial programs Huygens and Autoquant. Aberration correction available in the software dramatically reduced the axial blur compared to deconvolution that ignored the refractive index mismatch. At the same time, it failed to completely recover the cylindrical symmetry of bacteria or of actin fibres, which showed up to a three to five times larger width along the optical axis compared to the lateral plane. The quality of restoration was only moderately sensitive to the exact values of the specimen refractive index but in some cases improved significantly by assuming a reduced NA of the objective. Because image restoration depends on the knowledge of the vertical scale, we also performed detailed measurements of the axial scaling factor and concluded (in agreement with some previous authors) that scaling is adequately described by the simple paraxial formula, even when high-NA oil-immersion objectives are used.

DSC3 expression is regulated by p53, and methylation of DSC3 DNA is a prognostic marker in human colorectal cancer

Background:

Desmocollin 3 (DSC3), a member of the cadherin superfamily and integral component of desmosomes, is involved in carcinogenesis. However, the role of DSC3 in colorectal cancer (CRC) has not yet been established.

Methods:

Desmocollin 3 expression in CRC cell lines was analysed by RT–PCR and western blotting. Methylation status of DSC3 was examined by demethylation tests, methylation-specific PCR, and bisulphite sequencing (BS). The regulatory role of p53 was investigated by transfection.

Results:

Desmocollin 3 was downregulated in CRC cells at mRNA and protein levels. Desmocollin 3 expression was restored in five out of seven cell lines after 5-aza-2′-deoxycytidine (DAC) treatment. A heterogeneous methylation pattern was detected by BS in promoter region and exon 1 of DSC3. Methylation of DSC3 genomic sequences was found in 41% (41 out of 99) of primary CRC, being associated with poor prognosis (P=0.002). Transfection of p53 alone or in combination of DAC increased the DSC3 expression. Similarly, treatment with p53 inducer adriamycin alone or in combination with DAC enhanced DSC3 expression.

Conclusions:

DNA methylation contributes to downregulation of DSC3 in CRC cell lines. Methylation status of DSC3 DNA is a prognostic marker for CRC. P53 appears to have an important role in regulating DSC3 expression.

Multidrug-resistant tuberculosis is associated with low plasma concentrations of human neutrophil peptides 1-3

SETTING

Human neutrophil peptides 1, 2 and 3 (HNP1-3) are involved in innate host defence and acquired immune response, which is possibly associated with the genesis of multidrug-resistant tuberculosis (MDR-TB).

OBJECTIVE

To investigate the relationship between HNP1-3 and MDR-TB.

DESIGN

We divided 42 patients with post-primary pulmonary TB into two groups according to their drug susceptibility test results: the drug-susceptible group (n = 21) and the MDR-TB group (n = 21). The concentration of HNP1-3 in the plasma of all specimens was measured by enzyme-linked immunosorbent assay before treatment and 6, 18 and 24 months after. Duration of Mycobacterium tuberculosis in sputum and peripheral blood neutrophil counts were measured at the same time.

RESULTS

Before treatment, the plasma HNP1-3 concentration in the MDR-TB group was lower than that of healthy controls and the drug-susceptible group. After treatment, plasma HNP1-3 concentrations were higher than pre-treatment levels in the MDR-TB group, but were still lower than in healthy controls or the drug-susceptible group. The concentration of HNP1-3 was negatively correlated with the duration of M. tuberculosis in sputum, while it was positively correlated with neutrophils.

CONCLUSION

MDR-TB is associated with low plasma concentrations of HNP1-3.

Compound Semiconductor Nanocrystals formed by Sequential Ion Implantation

Ion implantation and thermal processing have been used to synthesize compound semiconductor nanocrystals (SiGe, GaAs, and CdSe) in both SiO2 and (0001) Al2O3. Equal doses of each constituent are implanted sequentially at energies chosen to give an overlap of the profiles. Subsequent annealing results in precipitation and the formation of compound nanocrystals. In SiO2 substrates, nanocrystals are nearly spherical and randomly oriented. In Al2O3, nanocrystals exhibit strong orientation both in-plane and along the surface normal.

Semiconductor Nanocrystals formed in SiO2 by Ion Implantation

Nanocrystals of group IV (Si, Ge and SiGe), III-V (GaAs), and II-VI (CdSe) semiconductor materials have been fabricated inside SiO2 by ion implantation and subsequent thermal annealing. The microstructure of these nanocrystalline semiconductor materials has been studied by transmission electron microscopy (TEM). The nanocrystals form in near-spherical shape with random crystal orientations in amorphous SiO2 Extensive studies on the nanocrystal size distributions have been carried out for the Ge nanocrystals by changing the implantation doses and the annealing temperatures. Remarkable roughening of the nanocrystals occurs when the annealing temperature is raised over the melting temperature of the implanted semiconductor material. Strong red photoluminescence peaked around 1.67 eV has been achieved in samples with Si nanocrystals in SiO2.

Measurement of the isolated prompt photon production cross section in pp collisions at √s=7 TeV

The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E(T)(γ) in pp collisions at √s=7  TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.9  pb(-1). Photons are required to have a pseudorapidity |η(γ)|<1.45 and E(T)(γ)>21  GeV, covering the kinematic region 0.006<x(T)<0.086. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations.

Demonstration of ignition radiation temperatures in indirect-drive inertial confinement fusion hohlraums

We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 μm diameter hot core.

Structural Defects in Heteroepitaxial and Homoepitaxial GaN

The microstructure and characteristic defects of heteroepitaxial GaN films grown on sapphire using molecular beam epitaxy (MBE) and metal-organic-chemical-vapor-deposition (MOCVD) methods and of homoepitaxial GaN grown on bulk substrates are described based on transmission electron microscopy (TEM), x-ray diffraction, and cathodoluminescence (CL) studies. The difference in arrangement of dislocations along grain boundaries and die influence of buffer layers on the quality of epitaxial films is described. The structural quality of GaN epilayers is compared to diat of bulk GaN crystals grown from dilute solution of atomic nitrogen in liquid gallium. The full width at half maximum (FWHM) of the x-ray rocking curves for these crystals was in the range of 20–30 arc sec, whereas for the heteroepitaxially grown GaN the FWHM was in the range of 5–20 arc min. Homoepitaxial MBE grown films had FWHMs of about 40 arc sec. The best film quality was obtained for homoepitaxial films grown using MOCVD; these samples were almost free from extended defects. For the bulk GaN crystals a substantial difference in crystal perfection was observed for the opposite sides of the plates shaped normal to the c direction. On one side the surface was almost atomically flat, and the underlying material was free of any extended structural defects, while the other side was rough, with a high density of planar defects. This difference was related to the polarity of the crystal. A large difference in crystal stoichiometry was also observed within different sublayers of the crystals. Based on convergent beam electron diffraction and cathodoluminescence, it is proposed that GaN antisite defects are related to the yellow luminescence observed in these crystals.

Confirmation of the X(1835) and observation of the resonances X(2120) and X(2370) in J/ψ→γπ+π-η'

With a sample of (225.2±2.8)×10(6) J/ψ events registered in the BESIII detector, J/ψ→γπ(+)π(-)η(') is studied using two η(') decay modes: η(')→π(+)π(-)η and η(')→γρ(0). The X(1835), which was previously observed by BESII, is confirmed with a statistical significance that is larger than 20σ. In addition, in the π(+)π(-)η(') invariant-mass spectrum, the X(2120) and the X(2370), are observed with statistical significances larger than 7.2σ and 6.4σ, respectively. For the X(1835), the angular distribution of the radiative photon is consistent with expectations for a pseudoscalar.

Thin Film Transistors of Microcrystalline Silicon Deposited by Plasma Enhanced-CVD

We fabricated top gate TFTs of microcrystalline silicon (μc-Si) deposited at 360 °C. The TFTs have field-effect electron mobilities of up to 7.9 cm2/Vs in the saturation regime and 5.8 cm2/Vs in the linear regime. The highest ION/IOFF ratio is 105. Typical values for Vth is 6.5 V and for the subthreshold slope is 1.7 V/decade. The μc-Si is grown by PE-CVD from a source gas mixture of SiH4, SiF4 and H2, with a typical flow ratio of 1:20:200, at a pressure of 120 Pa and a power density of 160 mW/cm2. The TFT structure is built on un-passivated Coming 7059 glass, with 300 n+ μc-Si, 60 nm n+ μc-Si source and drain contact layers, 200 nm SiO2 or 300 nm SiNx gate insulator, and 100 nm Al gate, source and drain electrodes.

Realization Of X-Ray Lithography Masks Based On Diamond Membranes

Deposition parameters acting on nucleation and growth local conditions have been optimized in a bell jar microwave plasma reactor to obtain polycrystalline diamond thin films compatible with X-ray membrane requests. The microstructure and the chemical quality of the films were estimated by SEM and Raman spectroscopy respectively, the roughness was evaluated by AFM experiments and the residual stress was deduced from the substrate deflection method. Membranes were obtained by removing the silicon substrate on 15 mm diameter circular windows. The optical transparency depending on deposition conditions was optimized up to 65% at 630 nm for 1 μm thickness. A high resolution additive mask process, based on well taut membranes and low stress electroplated gold absorber, was carried out. Micrometric and submicrometric mask patterns were generated in photoresists both by electron beam lithography with a nanopattern generator and by X-ray lithography using the synchrotron radiation facility implemented at LURE-Orsay. Despite the diamond films roughness of the order of 30 nm, well defined dots and lines as narrow as 100–200 nm could be obtained.

Botulinum toxin to control an incapacitating tic in a child with a clavicular fracture

We present the case of an 11-year-old boy who suffered from an undefined tic disorder and incidentally sustained a traumatic fracture of the clavicle. The fracture healing course was complicated by the tic activity, and the frequency and intensity of the tics were worsened by the presence of clavicular pain. He underwent surgery and his management required the collaboration of orthopaedic surgeons, the Acute Pain Service, neurologists for tic management and rehabilitation physicians who performed the intramuscular injections of botulinum toxin. We recommend a multidisciplinary and multimodal approach to managing patients suffering from tic disorders and highlight the consideration of intramuscular injections of botulinum toxin, which were successful for this patient.

Role of matrix metalloproteinase-8 in the modulation of systemic 5-fluorouracil pharmacokinetics by local irradiation

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Background: Concurrent chemoradiation with 5-fluorouracil (5-FU) is widely accepted for cancer treatment. However, the interactions between radiation and 5-FU remain unclear. We evaluated the influence of local irradiation on the pharmacokinetics of 5-FU in rats.

Methods: The single-fraction radiation was delivered to the whole pelvic fields of Sprague-Dawley rats from a linear accelerator after computerized tomography-based planning. 5-FU at 100 mg/kg was intravenously infused 24 hours after radiation. A high-performance liquid chromatography system equipped with a UV detector was used to measure 5-FU in the blood. Matrix metalloproteinase-8 (MMP-8) inhibitor I was administered to the rats to examine whether or not RT modulation of 5-FU pharmacokinetic parameters could be blocked.

Results: Compared with sham-irradiated controls, whole pelvic irradiation reduced the area under the concentration versus time curve (AUC) of 5-FU in plasma and, in contrast, increased the AUC in bile in a radiation dose-dependent manner. Based on protein array analysis, the amount of plasma MMP-8 was increased by whole pelvic irradiation (2.8-fold by 0.5 Gy and 5.3-fold by 2 Gy) in comparison with controls. Pretreatment with MMP-8 inhibitor reversed the effect of irradiation on AUC of 5-FU in plasma.

Conclusions: Local irradiation may modulate the systemic pharmacokinetics of 5-FU through stimulating the release of MMP-8. This unexpected influence is worthy of further investigation and for consideration in clinical practice of radiotherapy for cancer.

No significant financial relationships to disclose.