Loss of heterozygosity at 7p in Wilms' tumour development

Chromosome 7p alterations have been implicated in the development of Wilms' tumour (WT) by previous studies of tumour cytogenetics, and by our analysis of a constitutional translocation (t(1;7)(q42;p15)) in a child with WT and radial aplasia. We therefore used polymorphic microsatellite markers on 7p for a loss of heterozygosity (LOH) study, and found LOH in seven out of 77 informative WTs (9%). The common region of LOH was 7p15–7p22, which contains the region disrupted by the t(1;7) breakpoint. Four WTs with 7p LOH had other genetic changes; a germline WT1 mutation with 11p LOH, LOH at 11p, LOH at 16q, and loss of imprinting of IGF2. Analysis of three tumour-associated lesions from 7p LOH cases revealed a cystic nephroma-like area also having 7p LOH. However, a nephrogenic rest and a contralateral WT from the two other cases showed no 7p LOH. No particular clinical phenotype was associated with the WTs which showed 7p LOH. The frequency and pattern of 7p LOH demonstrated in our studies indicate the presence of a tumour suppressor gene at 7p involved in the development of Wilms' tumour. © 2000 Cancer Research Campaig

Lack of efficacy of troglitazone at clinically achievable concentrations, with or without 9-cis retinoic acid or cytotoxic agents, for hepatocellular carcinoma cell lines

[[abstract]]Although the PPARgamma agonist troglitazone has been shown to induce growth inhibition of hepatocellular carcinoma (HCC) cells at high concentration, this study indicates troglitazone does not significantly inhibit the growth of HCC cells at clinically achievable concentrations (1-10 muM), and this lack of activity could not be improved by the addition of 9-cis-retinoic acid. Furthermore, no synergistic effect was found between troglitazone and cytotoxic anticancer agents

Basic Atomic Physics

Contains reports on five research projects.Joint Services Electronics Program Contract DAAL03-92-C-0001Joint Services Electronics Program Grant DAAH04-95-1-0038National Science Foundation Grant PHY 92-21489U.S. Navy - Office of Naval Research Grant N00014-90-J-1322National Science Foundation Grant PHY 92-22768U.S. Army - Office of Scientific Research Grant DAAL03-92-G-0229U.S. Army - Office of Scientific Research Grant DAAL01-92-6-0197U.S. Navy - Office of Naval Research Grant N00014-89-J-1207Alfred P. Sloan FoundationU.S. Navy - Office of Naval Research Grant N00014-90-J-1642U.S. Navy - Office of Naval Research Grant N00014-94-1-080

Light Extraction Enhancement of n-side up Light-Emitting Diodes without Electrodes Covering by Wafer Bonding and Textured Surfaces

Textured n-side-up GaN LED with interdigitated imbedded electrodes (IIE) eliminating the electrode-shading loss with high reflection mirror and double-side roughening on both p-GaN and undoped-GaN layers have been investigated. The epitaxial layers of the device are grown on (0001) sapphire substrates by metal-organic chemical vapor deposition. The devices are subsequently fabricated with wafer-bonding, laser lift-off, chemical dry/wet etching techniques. This n-side up structure was useful to enhance light extraction and increase the light output power. We compared the performance of the luminance intensity(at 350 mA injection current), which is 78.85 % and 115.38 % higher than those of the conventional structure and the p-side up structure with high reflection mirror on silicon substrate with electrode shading, respectively

In vitro study of the carry-over effect associated with early diabetic embryopathy in the rat.

Embryos were recovered from diabetic rats on day 5 of pregnancy and incubated in vitro for up to 72 h. Compared to control embryos, blastocysts from diabetic rats showed a marked impairment in growth that resulted at 48 h in a higher rate of degeneration and a lower morphological score in the developing population. After 72 h in vitro, fewer developing blastocysts from diabetic rats formed trophoblastic outgrowths and fewer of those implanted developed an inner cell mass when compared with the control group. When assessed for their cell content, blastocysts from diabetic rats contained fewer cells than control embryos at the start of the culture. This difference persisted, and even worsened, during the ensuing incubation period. The increasing cellular deficiency in blastocysts from diabetic rats was primarily located to their inner cell mass lineage but trophoblast growth was also affected. When trophoblast outgrowths were compared for their surface area and number of nuclei, those collected from diabetic rats were smaller, contained fewer nuclei and had a higher proportion of giant nuclei than control outgrowths. Our data thus demonstrate that despite their removal from the abnormal intra-uterine environment, blastocysts from diabetic rats remain functionally affected by their early exposure and fare less well than control embryos cultured under the same standard conditions

Expression of tumor necrosis factor-alpha (TNF alpha) receptors and selective effect of TNF alpha on the inner cell mass in mouse blastocysts.

The presence of tumor necrosis factor-alpha (TNF alpha) receptors was demonstrated at the cell surface of mouse blastocysts by indirect immunofluorescence. Amplification of total cDNA from these embryos indicated that only the p60 form of the TNF alpha receptor was expressed. Amplification of the p80 form remained negative. Blastocysts were cultured with 0.5, 5.0, or 50 ng/ml TNF alpha and examined for their morphology and cell proliferation rate. Doses of 5.0 and 50 ng/ml delayed the morphological development after 24 h, but this effect was no longer detected after 48 h. Overall cell proliferation was decreased by 15% with 50 ng/ml TNF alpha after 24 h and with all three concentrations after 48 h. Differential staining of the two embryonic cell lineages revealed that the reduction in cell number was at the expense of the inner cell mass, the cell group responsible for forming the fetal layers after implantation. This inhibition was not mediated by cytotoxicity, as the proportion of dead ICM cells remained low in the presence of TNF alpha. Our data indicate that the expression of TNF alpha receptors is developmentally regulated before implantation, and that preimplantation embryos are responsive to TNF alpha

(Thin Solid Films, 516(5):747-750)Fabrication and characteristics of n-Si/c-Si/p-Si heterojunction solar cells using hot-wire CVD

A double-side (bifacial) heterojunction (HJ) Si solar cell was fabricated using hot-wire chemical vapor deposition. The properties of n-type, intrinsic and p-type Si films were investigated. In these devices, the doped microcrystal line Si layers (n-type Si for emitter and p-type Si for back contact) are combined with and without a thin intrinsic amorphous Si buffer layer. The maximum temperature during the whole fabrication process was kept below 150 'C. The influence of hydrogen pre-treatment and n-Si emitter thickness on performance of solar cells have been studied. The best bifacial Si HJ solar cell (I cm 2 sample) with an intrinsic layer yielded an active area conversion efficiency of 16.4% with an open circuit voltage of 0.645 V, short circuit current of 34.8 mA/cm(2) and fill factor of 0.73. (c) 2007 Elsevier B.V. All rights reserved