Combined optical and acoustical method for determination of thickness and porosity of transparent organic layers below the ultra-thin film limit

Analysis techniques are needed to determine the quantity and structure of materials composing an organic layer that is below an ultra-thin film limit and in a liquid environment. Neither optical nor acoustical techniques can independently distinguish between thickness and porosity of ultra-thin films due to parameter correlation. A combined optical and acoustical approach yields sufficient information to determine both thickness and porosity. We describe application of the combinatorial approach to measure single or multiple organic layers when the total layer thickness is small compared to the wavelength of the probing light. The instrumental setup allows for simultaneous in situ spectroscopic ellipsometry and quartz crystal microbalance dynamic measurements, and it is combined with a multiple-inlet fluid control system for different liquid solutions to be introduced during experiments. A virtual separation approach is implemented into our analysis scheme, differentiated by whether or not the organic adsorbate and liquid ambient densities are equal. The analysis scheme requires that the film be assumed transparent and rigid (non-viscoelastic). We present and discuss applications of our approach to studies of organic surfactant adsorption, self-assembled monolayer chemisorption, and multiple-layer target DNA sensor preparation and performance testing.

Conservative surgery in the management of a benign ovarian cystic teratoma presenting as a rectal mass: a case report

Ovarian cystic teratomas constitute 10-15% of all ovarian tumours and are the most common ovarian neoplasms found in adolescence and during pregnancy. Nevertheless, ovarian cystic teratomas have also been described in patients aged 1-91 years. We report an unusual case of a benign ovarian cystic teratoma presenting as a rectal mass that was managed surgically using radical resection by a multidisciplinary team. This case report highlights the importance of preoperative investigations including colonoscopy and radiological investigations. A dedicated pelvic radiologist/pathologist and the involvement of a multidisciplinary team at the time of initial diagnosis and a gynaecologist and colorectal surgeon at the time of surgery will lead to an accurate diagnosis and the most appropriate treatment. Although rare, erosion of an ovarian dermoid into the rectum should be considered in young women who have an atypical presentation and are found to have a lesion in the rectum with biopsies indicating benign pathology.

Rice dehydrin K-segments have in vitro antibacterial activity

Dehydrins are groups of plant proteins that have been shown to response to various environmental stimuli such as dehydration, elevated salinity, and low temperature. However, their roles in plant defense against microbes have not been demonstrated. In an attempt to discover plant antimicrobial proteins, we have screened a rice cDNA library and isolated several cDNAs coding for dehydrins. Protein extracts from Escherichia coli expressing these cDNAs were tested for their activity against Gram-positive bacteria (Bacillus pumilus, B. subtilis, Staphylococcus aureus, and Sarcina lutea) and Gram-negative bacteria (Escherichia coli and Xanthomonas oryzae pv. oryzae). The results indicate that the crude protein extracts exhibited antibacterial activities against the Gram-positive bacteria. However, dehydrins purified by immunoaffinity chromatography were not active against the bacteria. To pinpoint the dehydrin peptides that were responsible for the bactericidal activity, we expressed DNA sequences coding for truncated dehydrins containing either K- or S-segment and found that K-segment peptides, and not S-segment, were responsible for the antibacterial activities against Gram-positive bacteria. Antibacterial assay with synthetic K-segments indicated that the peptides inhibited growth of B. pumilus with minimum inhibition concentration and minimum bactericidal concentration of 130 and 400 μg/ml, respectively.

Hic-5 controls BMP4 responses in prostate cancer cells through interacting with Smads 1, 5 and 8

Hydrogen peroxide-inducible clone-5 (Hic-5, or androgen receptor-associated protein 55) is a transforming growth factor-β (TGF-β)-inducible LIM protein whose deregulation is implicated in the progression of prostate cancer. Here we report that Hic-5 binds to Smads 1, 5 and 8, and represses bone morphogenetic protein (BMP) signaling responses. Myc-Hic-5 but not Myc-paxillin was specifically immunoprecipitated with anti-FLAG IgG1 from lysates of HEK293 co-transfected with either Myc-Hic-5 or Myc-paxillin and FLAG-tagged Smads 1, 5 or 8. We showed that such interactions require the LIM3 domain of Hic-5 and the MH2 domain of those Smads. Anti-Hic-5 antibody specifically pulled down endogenous Smad1 in both the PC3 human prostate cell line and primary cultures of rat prostate fibroblasts, supporting that Hic-5 binds to Smad1 at the endogenous level. Bacterially expressed GST-Smads 1, 5 or 8, but not GST alone, pulled down in vitro transcribed and translated Hic-5, implicating that Hic-5 binds directly to Smads 1, 5 and 8. Significantly, using Hic-5 shRNA silencing and overexpression systems, we show that Hic-5 (at both the endogenous and exogenous levels) represses the ability of BMP4 to induce expression of the inhibitor of differentiation-1 (Id1) (a downstream target gene of BMP), activate the Id1 gene promoter and induce apoptosis in human and rat prostate epithelial cells. Moreover, silencing of Hic-5 in PC3 cells as well as in the WPMY-1 human prostate stroma cell line greatly enhances the levels of endogenous phospho-Smad1/5/8. Finally, we provide fluorescent microscopic imaging to support that Smad1 and Hic-5 mutually interact also at the level of their nuclear export mechanisms. Collectively, these results provide the first evidence for a physical and mutual functional interaction between Hic-5 and the BMP signaling pathway.

Dark matter results from 100 live days of XENON100 data

We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time-projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows the selection of only the innermost 48 kg as the ultralow background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in the signal region with an expected background of (1.8 ± 0.6) events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic weakly interacting massive particle (WIMP) nucleon scattering cross sections above 7.0 × 10(-45) cm(2) for a WIMP mass of 50 GeV/c(2) at 90% confidence level.

A novel SNP of the C/EBPα gene associated with superior meat quality in indigenous Chinese cattle

CCAAT/enhancer-binding protein alpha (C/EBPα) is an essential transcriptional factor regulating the differentiation of adipocytes. We report a novel single nucleotide polymorphism (C271A) of the C/EBPα gene in six indigenous Chinese cattle breeds using PCR-SSCP and DNA sequencing methods. Allele frequencies were investigated and evaluated by the χ(2) test in 817 individuals; all populations were found to be in Hardy-Weinberg equilibrium. Gene heterozygosity, effective allele numbers and polymorphism information content of the C/EBPα locus varied from 0.50 to 0.54, 1.84 to 1.99 and 0.35 to 0.37, respectively. We also evaluated a potential association of the C/EBPα SNP with ultrasound traits in 555 individuals; individuals of the AA genotype had greater ultrasound backfat thickness than did genotype CC (0.36 versus 0.34 cm, P < 0.01); genotypes AA and CA had higher ultrasound marbling scores than did genotype CC (3.53, 3.52 versus 3.37, P < 0.05). Analysis based on meat quality data in another 204 Qinchuan cattle showed that animals with genotype AA had bigger loin eye areas than did genotype CA (87.10 versus 79.08 cm(2), P < 0.05). These results indicate that the C271A SNP of the C/EBPα gene could be used as a molecular marker for selecting beef cattle with superior carcass traits.