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in creator/contributor: "Lawrence Berkeley National Laboratory. Life Sciences Division."

open access

Three-dimensional lithographically-defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression

Here we describe a simple micromolding method to construct three-dimensional arrays of organotypic epithelial tissue structures that approximate in vivo histology. An elastomeric stamp containing an array of posts of defined geometry and spacing is used to mold microscale cavities into the surface of type I collagen gels. Epithelial cells are seeded into the cavities and covered with a second layer of collagen. The cells reorganize into hollow tissues corresponding to the geometry of the caviti… more

Date: February 13, 2008

Creator: Nelson, Celeste M.; Inman, Jamie L. & Bissell, Mina J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Separation of Iron and Cobalt on Synthetic Resin

In the separation of mixtures of radioactive iron and cobalt from neutron irradiated targets and in the removal of iron from cobalt targets for cyclotron production of radioiron, it is desirable to have a method superior to extraction from isopropyl ether in efficiency and ease of manipulation. Recent studies by Moore and Kraus on the separation of cobalt and nickel and on the behavior of iron in hydrochloric acid on Dowex-l resin in relation to the selective adsorption of chloride complexes of… more

Date: August 5, 1953

Creator: Helwig, H. L.; Ashikawa, J. K.; Clokie, H. & Smith, E. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Early Brain Response to Low-Dose Radiation Exposure Involves Molecular Networks and Pathways Associated with Cognitive Functions, Advanced Aging and Alzheimer's Disease

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with uni… more

Date: June 6, 2008

Creator: Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco & Wyrobek, Andrew J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

SYNTHESIS OF THE FULLY PROTECTED PHOSPHORAMIDITE OF THE BENZENE-DNA ADDUCT, N2- (4-HYDROXYPHENYL)-2'-DEOXYGUANOSINE AND INCORPORATION OF THE LATER INTO DNA OLIGOMERS

N2-(4-Hydroxyphenyl)-2'-deoxyguanosine-5'-O-DMT-3'-phosphoramidite has been synthesized and used to incorporate the N2-(4-hydroxyphenyl)-2'-dG (N2-4-HOPh-dG) into DNA, using solid-state synthesis technology. The key step to obtaining the xenonucleoside is a palladium (Xantphos-chelated) catalyzed N2-arylation (Buchwald-Hartwig reaction) of a fully protected 2'-deoxyguanosine derivative by 4-isobutyryloxybromobenzene. The reaction proceeded in good yield and the adduct was converted to the requi… more

Date: June 9, 2008

Creator: Chenna, Ahmed; Gupta, Ramesh C.; Bonala, Radha R.; Johnson, Francis & Huang, Bo

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cell Cycle Related Differentiation of Bone Marrow Cells into Lung Cells

Green-fluorescent protein (GFP) labeled marrow cells transplanted into lethally irradiated mice can be detected in the lungs of transplanted mice and have been shown to express lung specific proteins while lacking the expression of hematopoietic markers. We have studied marrow cells induced to transit cell cycle by exposure to IL-3, IL-6, IL-11 and steel factor at different times of culture corresponding to different phases of cell cycle. We have found that marrow cells at the G1/S interface ha… more

Date: December 31, 2007

Creator: Dooner, Mark; Aliotta, Jason M.; Pimental, Jeffrey; Dooner, Gerri J.; Abedi, Mehrdad; Colvin, Gerald et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

DNA repair decline during mouse spermiogenesis results in the accumulation of heritable DNA damage

The post-meiotic phase of mouse spermatogenesis (spermiogenesis) is very sensitive to the genomic effects of environmental mutagens because as male germ cells form mature sperm they progressively lose the ability to repair DNA damage. We hypothesized that repeated exposures to mutagens during this repair-deficient phase result in the accumulation of heritable genomic damage in mouse sperm that leads to chromosomal aberrations in zygotes after fertilization. We used a combination of single or fr… more

Date: February 21, 2008

Creator: Marchetti, Francesco; Marchetti, Francesco & Wryobek, Andrew J

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Scintillation and Luminescence Properties of Undoped and Cerium-doped LiGdCl4 and NaGdCl4

We report the scintillation properties of the undoped and cerium-doped variations of LiGdCl4 and NaGdCl4. Powder samples of these materials exhibit significant scintillation under X-rays. The samples were synthesized by solid-state methods from a 1:1 molar ratio of lithium or sodium chloride and gadolinium chloride. Cerium trichloride was used as the dopant. The physical, optical, and scintillation properties of these materials were analyzed by powder X-ray diffraction, photoluminescence, X-ray… more

Date: October 5, 2008

Creator: Porter-Chapman, Yetta D.; Bourret-Courchesne, Edith D.; Bizarri, Gregory; Weber, Marvin J. & Derenzo, Stephen E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The Laminin 511/521 Binding Site on the Lutheran Blood Group Glycoprotein is Located at theFlexible Junction of Ig Domains 2 and 3

The Lutheran blood group glycoprotein, first discovered on erythrocytes, is widely expressed in human tissues. It is a ligand for the {alpha}5 subunit of Laminin 511/521, an extracellular matrix protein. This interaction may contribute to vasocclusive events that are an important cause of morbidity in sickle cell disease. Using X-ray crystallography, small angle X-ray scattering and site directed mutagenesis we show that the extracellular region of Lutheran forms an extended structure with a di… more

Date: July 1, 2007

Creator: Mankelow, Tosti J.; Burton, Nicholas; Stedansdottir, Fanney O.; Spring, Frances A.; Parsons, Stephen F.; Pesersen, Jan S. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Task Group 7B: Cellular and Molecular Mechanisms of Biological Aging: The Roles of Nature, Nurture and Chance in the Maintenance of Human Healthspan

The degree to which an individual organism maintains healthspan and lifespan is a function of complex interactions between genetic inheritance ('nature'), environment, including cultural inheritance (nurture) and stochastic events ('luck' or 'chance'). This task group will focus upon the role of chance because it is so poorly understood and because it appears to be of major importance in the determination of individual variations in healthspan and lifespan within species. The major factor deter… more

Date: November 14, 2007

Creator: Weier, Heinz-Ulrich; Arya, Suresh; Grant, Christine; Miller, Linda; Ono, Santa Jeremy; Patil, Chris et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A CCD Camera with Electron Decelerator for Intermediate Voltage Electron Microscopy

Electron microscopists are increasingly turning to Intermediate Voltage Electron Microscopes (IVEMs) operating at 300 - 400 kV for a wide range of studies. They are also increasingly taking advantage of slow-scan charge coupled device (CCD) cameras, which have become widely used on electron microscopes. Under some conditions CCDs provide an improvement in data quality over photographic film, as well as the many advantages of direct digital readout. However, CCD performance is seriously degraded… more

Date: March 17, 2008

Creator: Downing, Kenneth H; Downing, Kenneth H. & Mooney, Paul E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

TRWG developmental pathway for biospecimen-based assessment modalities

The Translational Research Working Group (TRWG) was created as a national initiative to evaluate the current status of NCI's investment in translational research and envision its future. The TRWG conceptualized translational research as a set of six developmental processes or pathways focused on various clinical goals. One of those pathways describes the development of biospecimen-based assays that utilize biomarkers for the detection, diagnosis, prognosis, and assessment of response to cancer … more

Date: September 3, 2008

Creator: Group, Translational Research Working; Srivastava, Sudhir; Gray, Joe W.; Reid, Brian J.; Grad, Oren; Greenwood, Addison et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

PointCloudExplore 2: Visual exploration of 3D gene expression

To better understand how developmental regulatory networks are defined inthe genome sequence, the Berkeley Drosophila Transcription Network Project (BDNTP)has developed a suite of methods to describe 3D gene expression data, i.e.,the output of the network at cellular resolution for multiple time points. To allow researchersto explore these novel data sets we have developed PointCloudXplore (PCX).In PCX we have linked physical and information visualization views via the concept ofbrushing (cell … more

Date: March 31, 2008

Creator: International Research Training Group Visualization of Large and Unstructured Data Sets, University of Kaiserslautern, Germany; Institute for Data Analysis and Visualization, University of California, Davis, CA; Computational Research Division, Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA; Genomics Division, LBNL; Computer Science Department, University of California, Irvine, CA; Computer Science Division,University of California, Berkeley, CA et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Measuring Regional Changes in the Diastolic Deformation of the Left Ventricle of SHR Rats Using microPET Technology and Hyperelastic Warping

The objective of this research was to assess applicability of a technique known as hyperelastic warping for the measurement of local strains in the left ventricle (LV) directly from microPET image data sets. The technique uses differences in image intensities between template (reference) and target (loaded) image data sets to generate a body force that deforms a finite element (FE) representation of the template so that it registers with the target images. For validation, the template image was… more

Date: April 4, 2008

Creator: Gullberg, Grant T; Veress , Alexander I.; Weiss, Jeffrey A.; Huesman, Ronald H.; Reutter, Bryan W.; Taylor , Scott E. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A human breast cell model of pre-invasive to invasive transition

A crucial step in human breast cancer progression is the acquisition of invasiveness. There is a distinct lack of human cell culture models to study the transition from pre-invasive to invasive phenotype as it may occur 'spontaneously' in vivo. To delineate molecular alterations important for this transition, we isolated human breast epithelial cell lines that showed partial loss of tissue polarity in three-dimensional reconstituted-basement membrane cultures. These cells remained non-invasive;… more

Date: March 10, 2008

Creator: Bissell, Mina J; Rizki, Aylin; Weaver, Valerie M.; Lee, Sun-Young; Rozenberg, Gabriela I.; Chin, Koei et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Attenuated Vector Tomography -- An Approach to Image Flow Vector Fields with Doppler Ultrasonic Imaging

The measurement of flow obtained using continuous wave Doppler ultrasound is formulated as a directional projection of a flow vector field. When a continuous ultrasound wave bounces against a flowing particle, a signal is backscattered. This signal obtains a Doppler frequency shift proportional to the speed of the particle along the ultrasound beam. This occurs for each particle along the beam, giving rise to a Doppler velocity spectrum. The first moment of the spectrum provides the directional… more

Date: May 15, 2008

Creator: Huang, Qiu; Peng, Qiyu; Huang, Bin; Cheryauka, Arvi & Gullberg, Grant T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Restoration of Weak Phase-Contrast Images Recorded With a High Degree of Defocus: The "Twin Image" Problem Associated With CTF Correction

Relatively large values of objective-lens defocus must normally be used to produce detectable levels of image contrast for unstained biological specimens, which are generally weak phase objects. As a result, a subsequent restoration operation must be used to correct for oscillations in the contrast transfer function (CTF) at higher resolution. Currently used methods of CTF-correction assume the ideal case in which Friedel mates in the scattered wave have contributed pairs of Fourier components … more

Date: March 28, 2008

Creator: Downing, Kenneth H. & Glaeser, Robert M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Translating the cancer genome: Going beyond p values

Cancer cells are endowed with diverse biological capabilities driven by myriad inherited and somatic genetic and epigenetic aberrations that commandeer key cancer-relevant pathways. Efforts to elucidate these aberrations began with Boveri's hypothesis of aberrant mitoses causing cancer and continue today with a suite of powerful high-resolution technologies that enable detailed catalogues of genomic aberrations and epigenomic modifications. Tomorrow will likely bring the complete atlas of rever… more

Date: April 3, 2008

Creator: Chin, Lynda; Chin, Lynda & Gray, Joe W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

PREFERENTIAL INHIBITION OF THE GROWTH OF VIRUS-TRANSFORMED CELLS IN CULTURE BY RIFAZONE-82, A NEW RIFAMYCIN DERIVATIVE

Rifazone-8{sub 2} (R-8{sub 2}), a new rifamycin derivative, is shown to preferentially inhibit the growth of virus-transformed chick cells in culture. Macromolecular synthesis and glucose uptake of transformed cells are also appreciably decreased in the presence of low concentrations of R-8{sub 2} where the normal cells appear unaffected. While R-8{sub 2} is shown to be a selective inhibitor of RNA-directed DNA polymerase in vitro, its action on the growth of transformed cells may involve some … more

Date: March 28, 1974

Creator: Bissell, Mina J.; Hatie, Carroll; Tischler, Allan N. & Calvin, Melvin.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ovarian carcinomas with genetic and epigenetic BRCA1 loss have distinct molecular abnormalities

Subclassification of ovarian carcinomas can be used to guide treatment and determine prognosis. Germline and somatic mutations, loss of heterozygosity (LOH), and epigenetic events such as promoter hypermethylation can lead to decreased expression of BRCA1/2 in ovarian cancers. The mechanism of BRCA1/2 loss is a potential method of subclassifying high grade serous carcinomas. A consecutive series of 49 ovarian cancers was assessed for mutations status of BRCA1 and BRCA2, LOH at the BRCA1 and BRC… more

Date: May 2, 2008

Creator: Gilks, C. Blake; Press, Joshua Z.; De Luca, Alessandro; Boyd, Niki; Young, Sean; Troussard, Armelle et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

beta 1 integrin inhibition dramatically enhances radiotherapy efficacy in human breast cancer xenografts

{beta}1 integrin signaling has been shown to mediate cellular resistance to apoptosis after exposure to ionizing radiation (IR). Other signaling molecules that increase resistance include Akt, which promotes cell survival downstream of {beta}1 integrin signaling. We showed previously that {beta}1 integrin inhibitory antibodies, AIIB2, enhance apoptosis and decrease growth in human breast cancer cells in 3 dimensional laminin-rich extracellular matrix (3D lrECM) cultures and in vivo. Here we ask… more

Date: June 2, 2008

Creator: Park, Catherine C.; Park, Catherine C.; Zhang, Hui J.; Yao, Evelyn S.; Park, Chong J. & Bissell, Mina J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Regulation of in situ to invasive breast carcinoma transition

The transition of ductal carcinoma in situ (DCIS) to invasive carcinoma is a key event in breast tumor progression that is poorly understood. Comparative molecular analysis of tumor epithelial cells from in situ and invasive tumors has failed to identify consistent tumor stage-specific differences. However, the myoepithelial cell layer, present only in DCIS, is a key distinguishing and diagnostic feature. To determine the contribution of non-epithelial cells to tumor progression, we analyzed th… more

Date: May 7, 2008

Creator: Polyak, Kornelia; Hu, Min; Yao, Jun; Carroll, Danielle K.; Weremowicz, Stanislawa; Chen, Haiyan et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Telomere dysfunction and cell survival: Roles for distinct TIN2-containing complexes

Telomeres are maintained by three DNA binding proteins (TRF1, TRF2 and POT1), and several associated factors. One factor, TIN2, binds TRF1 and TRF2 directly and POT1 indirectly. Along with two other proteins, TPP1 and hRap1, these form a soluble complex that may be the core telomere maintenance complex. It is not clear whether sub-complexes also exist in vivo. We provide evidence for two TIN2 sub-complexes with distinct functions in human cells. We isolated these two TIN2 sub-complexes from nuc… more

Date: October 2, 2007

Creator: Kim, Sahn-ho; Davalos, Albert R.; Heo, Seok-Jin; Rodier, Francis; Zou, Ying; Beausejour, Christian et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Repair of radiation-induced heat-labile sites is independent of DNA-PKcs, XRCC1 or PARP

Ionizing radiation induces a variety of different DNA lesions: in addition to the most critical DNA damage, the DSB, numerous base alterations, SSBs and other modifications of the DNA double-helix are formed. When several non-DSB lesions are clustered within a short distance along DNA, or close to a DSB, they may interfere with the repair of DSBs and affect the measurement of DSB induction and repair. We have previously shown that a substantial fraction of DSBs measured by pulsed-field gel elec… more

Date: April 29, 2008

Creator: Stenerlöw, Bo; Karlsson, Karin H.; Radulescu, Irina; Rydberg, Bjorn & Stenerlow, Bo

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Laminin and biomimetic extracellular elasticity enhance functional differentiation in mammary epithelia

In the mammary gland, epithelial cells are embedded in a 'soft' environment and become functionally differentiated in culture when exposed to a laminin-rich extracellular matrix gel. Here, we define the processes by which mammary epithelial cells integrate biochemical and mechanical extracellular cues to maintain their differentiated phenotype. We used single cells cultured on top of gels in conditions permissive for {beta}-casein expression using atomic force microscopy to measure the elastici… more

Date: October 20, 2008

Creator: Alcaraz, Jordi; Xu, Ren; Mori, Hidetoshi; Nelson, Celeste M.; Mroue, Rana; Spencer, Virginia A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department