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in subjects: "Collagen"

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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

The mechanics of soft biological composites.

Biological tissues are uniquely structured materials with technologically appealing properties. Soft tissues such as skin, are constructed from a composite of strong fibrils and fluid-like matrix components. This was the first coordinated experimental/modeling project at Sandia or in the open literature to consider the mechanics of micromechanically-based anisotropy and viscoelasticity of soft biological tissues. We have exploited and applied Sandia's expertise in experimentation and mechanics … more

Date: October 1, 2007

Creator: Nguyen, Thao D. (Sandia National Laboratories, Livermore, CA); Grazier, John Mark; Boyce, Brad Lee & Jones, Reese E. (Sandia National Laboratories, Livermore, CA)

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Raft River Geothermal Aquaculture Experiment-Phase II

Channel catfish, tilapia and Malaysian prawns were cultured directly in geothermal water for approximately seven months at the Department of Energy, Raft River Geothermal Site, to evaluate the organisms throughout a grow-out cycle. Parameters evaluated included survival, growth, bioaccumulation of metals and fluoride, collagen synthesis, and bone calcium levels. Growth at Raft River was slightly lower than at a companion commercial facility at Buhl, Idaho, but was attributed to facility differe… more

Date: August 1, 1979

Creator: Campbell, Donald K.; Rose, Fred L.; Kent, James C.; Watson, Lynn R. & Sullivan, Jacquelyn F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Polycyclic aromatic hydrocarbon-protein interactions. Progress report, March 1, 1979-February 28, 1980

As bovine serum albumin (BSA) undergoes acid- or base-induced conformational changes, the binding of benzo(a)pyrene (BaP) to BSA, as well as the type II uv fluorescence (380 nm) due to pyrene-like oxidation products, increases. The presence of fatty acids also enhances the binding of BaP to BSA at neutral pH, whereas the visible fluorescence of BaP is effectively quenched by fatty acids. L-Tryptophan, which is specifically bound to BSA, enhances the BaP binding and particularly the formation of… more

Date: October 1, 1979

Creator: Fujimori, E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Pathogenic mechanism in lung fibrosis. [Synergistic effects of BHT, O/sub 2/, and x rays in mice]

The purpose of the study was to examine whether an interaction between two agents causing alveolar epithelial damage would produce lung fibrosis. In mouse lung, intraperitoneal injection of the antioxidant butylated hydroxytoluene causes diffuse alveolar type I cell necrosis, followed by proliferation of type II alveolar cells. In animals exposed to 70% O/sub 2/ or 100-200 rad x rays during the phase of type II cell proliferation following BHT, diffuse interstitial lung fibrosis developed withi… more

Date: January 1, 1979

Creator: Witschi, H.; Haschek, W. M.; Meyer, K. R.; Ullrich, R. L. & Dalbey, W. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Molecular mapping of chromosomes 17 and X

Progress toward the construction of high density genetic maps of chromosomes 17 and X has been made by isolating and characterizing a relatively large set of polymorphic probes for each chromosome and using these probes to construct genetic maps. We have mapped the same polymorphic probes against a series of chromosome breakpoints on X and 17. The probes could be assigned to over 30 physical intervals on the X chromosome and 7 intervals on 17. In many cases, this process resulted in improved ch… more

Date: January 15, 1991

Creator: Barker, D. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

A low temperature scanning force microscope for biological samples

An SFM has been constructed capable of operating at 143 K. Two contributions to SFM technology are described: a new method of fabricating tips, and new designs of SFM springs that significantly lower the noise level. The SFM has been used to image several biological samples (including collagen, ferritin, RNA, purple membrane) at 143 K and room temperature. No improvement in resolution resulted from 143 K operation; several possible reasons for this are discussed. Possibly sharper tips may help.… more

Date: May 1, 1993

Creator: Gustafsson, M. G. L.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Molecular mapping of chromosomes 17 and X. Progress report

Date: January 15, 1991

Creator: Barker, D. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Effects of polar solvents on the fracture resistance of dentin: Role of water hydration

Although healthy dentin is invariably hydrated in vivo, from a perspective of examining the mechanisms of fracture in dentin, it is interesting to consider the role of water hydration. Furthermore, it is feasible that exposure to certain polar solvents, e.g., those found in clinical adhesives, can induce dehydration. In the present study, in vitro deformation and fracture experiments, the latter involving a resistance-curve (R-curve) approach (i.e., toughness evolution with crack extension), we… more

Date: December 10, 2004

Creator: Ritchie, R. O.; Nalla, R. K.; Balooch, M.; Ager, J. W., III; Kruzic, J. J. & Kinney, J. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effect of Structural Modification on Second Harmonic Generation in Collagen

The effects of structural perturbation on second harmonic generation in collagen were investigated. Type I collagen fascicles obtained from rat tails were structurally modified by increasing nonenzymatic cross-linking, by thermal denaturation, by collagenase digestion, or by dehydration. Changes in polarization dependence were observed in the dehydrated samples. Surprisingly, no changes in polarization dependence were observed in highly crosslinked samples, despite significant alterations in pa… more

Date: April 4, 2003

Creator: Stoller, P C; Reiser, K M; Celliers, P M & Rubenchik, A M

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Misregulation of Stromelysin-1 in Mouse Mammary Tumor Cells Accompanies Acquisition of Stromelysin-1 dependent Invasive Properties

Stromelysin-1 is a member of the metalloproteinase family of extracellular matrix-degrading enzymes that regulates tissue remodeling. We previously established a transgenic mouse model in which rat stromelysin-1 targeted to the mammary gland augmented expression of endogenous stromelysin-1, disrupted functional differentiation, and induced mammary tumors. A cell line generated from an adenocarcinoma in one of these animals and a previously described mammary tumor cell line generated in culture … more

Date: February 21, 1997

Creator: Lochter, A.; Srebrow, A.; Sympson, C.J.; Terracio, N.; Werb, Z. & Bissell, M.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Glucose Metabolite Patterns as Markers of Functional Differentiation in Freshly Isolated and Cultured Mouse Mammary Epithelial Cells

In the mammary gland of nonruminant animals, glucose is utilized in a characteristic and unique way during lactation. We have measured the incorporation of glucose carbon from [U-{sup 14}C] glucose into intermediary metabolites and metabolic products in mammary epithelial cells from virgin, pregnant, and lactating mice and demonstrate that glucose metabolite patterns can be used to recognize stages of differentiated function. For these cells, the rates of synthesis of glycogen and lactose, the … more

Date: June 1, 1980

Creator: Emerman, J. T.; Bartley, J. C. & Bissell, M. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Targeted Expression of Stromelysin-1 in Mammary Gland Provides Evidence for a Role of Proteinases in Branching Morphogenesis and the Requirement for an Intact Basement Membrane for Tissue-specific Gene Expression

The extracellular matrix (ECM) is an important regulator of the differentiated phenotype of mammary epithelial cells in culture. Despite the fact that ECM-degrading enzymes have been implicated in morphogenesis and tissue remodeling, there is little evidence for a direct role for such regulation in vivo. We generated transgenic mice that express autoactivated isoforms of the matrix metalloproteinase stromelysin-1, under the control of the whey acidic protein gene promoter, to examine the effect… more

Date: May 1, 1994

Creator: Sympson, Carolyn J; Talhouk, Rabih S; Alexander, Caroline M; Chin, Jennie R; Cliff, Shirley M; Bissell, Mina J et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Modeling the coupled mechanics, transport, and growth processes in collagen tissues.

The purpose of this project is to develop tools to model and simulate the processes of self-assembly and growth in biological systems from the molecular to the continuum length scales. The model biological system chosen for the study is the tendon fiber which is composed mainly of Type I collagen fibrils. The macroscopic processes of self-assembly and growth at the fiber scale arise from microscopic processes at the fibrillar and molecular length scales. At these nano-scopic length scales, we e… more

Date: November 1, 2006

Creator: Holdych, David J.; Nguyen, Thao D.; Klein, Patrick A.; in't Veld, Pieter J. & Stevens, Mark Jackson

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Estrogen and progesterone receptors have distinct roles in the establishment of the hyperplastic phenotype in PR-A transgenic mice

Expression of the A and B forms of progesterone receptor (PR) in an appropriate ratio is critical for mammary development. Mammary glands of PR-A transgenic mice, carrying an additional A form of PR as a transgene, exhibit morphological features associated with the development of mammary tumors. Our objective was to determine the roles of estrogen (E) and progesterone (P) in the genesis of mammary hyperplasias/preneoplasias in PR-A transgenics. We subjected PR-A mice to hormonal treatments and … more

Date: May 11, 2009

Creator: Simian, Marina; Bissell, Mina J.; Barcellos-Hoff, Mary Helen & Shyamala, Gopalan

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Expression of Autoactivated Stromelysin-1 in Mammary Glands of Transgenic Mice Leads to a Reactive Stroma During Early Development

Extracellular matrix and extracellular matrix-degrading matrix metalloproteinases play a key role in interactions between the epithelium and the mesenchyme during mammary gland development and disease. In patients with breast cancer, the mammary mesenchyme undergoes a stromal reaction, the etiology of which is unknown. We previously showed that targeting of an autoactivating mutant of the matrix metalloproteinase stromelysin-1 to mammary epithelia of transgenic mice resulted in reduced mammary … more

Date: April 24, 1998

Creator: Thomasset, N.; Lochter, A.; Sympson, C.J.; Lund, L.R.; Williams, D.R.; Behrendtsen, O. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A Novel Function for the nm23-Hl Gene: Overexpression in Human Breast Carcinoma Cells Leads to the Formation of Basement Membrane and Growth Arrest

We have developed a culture system using reconstituted basement membrane components in which normal human mammary epithelial cells exhibit several aspects of the development and differentiation process, including formation of acinar-like structures, production and basal deposition of basement membrane components, and production and apical secretion of sialomucins. Cell lines and cultures from human breast carcinomas failed to recapitulate this process. The data indicate the importance of cellul… more

Date: January 1, 1994

Creator: Howlett, Anthony R; Petersen, Ole W; Steeg, Patricia S & Bissell, Mina J

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cellular growth and survival are mediated by beta 1 integrins in normal human breast epithelium but not in breast carcinoma

We previously established a rapid three-dimensional assay for discrimination of normal and malignant human breast epithelial cells using a laminin-rich reconstituted basement membrane. In this assay, normal epithelial cells differentiate into well-organized acinar structures whereas tumor cells fail to recapitulate this process and produce large, disordered colonies. The data suggest that breast acinar morphogenesis and differentiation is regulated by cell-extracellular matrix (ECM) interaction… more

Date: November 28, 1994

Creator: Howlett, Anthony R; Bailey, Nina; Damsky, Caroline; Petersen, Ole W & Bissell, Mina J

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Plutonium-induced lymphadenitis in beagles

No Description Available.

Date: January 1, 1974

Creator: Dagle, G E & Park, J F

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion … more

Date: June 29, 1998

Creator: Lochter, Andre; Navre, Marc; Werb, Zena & Bissell, Mina J

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Mineralization of Synthetic Polymer Scaffolds: A Bottom-upApproach for the Development of Artificial Bone

The controlled integration of organic and inorganic components confers natural bone with superior mechanical properties. Bone biogenesis is thought to occur by templated mineralization of hard apatite crystals by an elastic protein scaffold, a process we sought to emulate with synthetic biomimetic hydrogel polymers. Crosslinked polymethacrylamide and polymethacrylate hydrogels were functionalized with mineral-binding ligands and used to template the formation of hydroxyapatite. Strong adhesion … more

Date: September 27, 2004

Creator: Song, Jie; Viengkham, Malathong & Bertozzi, Carolyn R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Confocal Imaging of Biological Tissues Using Second Harmonic Generation

A confocal microscopy imaging system was devised to selectively detect Second harmonic signals generated by biological tissues. Several types of biological tissues were examined using this imaging system, including human teeth, bovine blood vessels, and chicken skin. All these tissues generated strong second harmonic signals. There is considerable evidence that the source of these signals in tissue is collagen. Collagen, the predominant component of most tissues, is known to have second order n… more

Date: March 6, 2000

Creator: Kim, B. M.; Stoller, P.; Reiser, K.; Eichler, J.; Yan, M.; Rubenchik, A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

In vivo argon laser vascular welding using thermal feedback: open and closed loop patency and collagen crosslinking

An in vivo study of vascular welding with a fiber-delivered argon laser was conducted using a canine model. Longitudinal arteriotomies and venotomies were treated on femoral vein and artery. Laser energy was delivered to the vessel wall via a 400 {micro}m optical fiber. The surface temperature at the center of the laser spot was monitored in real time using a hollow glass optical fiber-based two-color infrared thermometer. The surface temperature was limited by either a room-temperature saline … more

Date: February 28, 1997

Creator: Small, W., LLNL

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Radiological Physics Division Annual Report, July 1964-June 1965

No Description Available.

Date: October 31, 1966

Item Type: Report

Partner: UNT Libraries Government Documents Department