gebhart/patrepeval huggingface dataset:
Self-Supporting Nanoclay as Internal Scaffold Material for Direct Printing of Soft Hydrogel Composite Structures in Air (2017)

Three dimensional (3D) bioprinting technology enables the freeform fabrication of complex constructs from various hydrogels and is receiving increasing attention in tissue engineering. The objective of this study is to develop a novel self-supporting direct hydrogel printing approach to extrude complex 3D hydrogel composite structures in air without the help of a support bath. Laponite, a member of the smectite mineral family, is investigated to serve as an internal scaffold material for the direct printing of hydrogel composite structures in air. In the proposed printing approach, due to its yield-stress property, Laponite nanoclay can be easily extruded through a nozzle as a liquid and self-supported after extrusion as a solid. Its unique crystal structure with positive and negative charges enables it to be mixed with many chemically and physically cross-linked hydrogels, which makes it an ideal internal scaffold material for the fabrication of various hydrogel structures. By mixing Laponite nanoclay with various hydrogel precursors, the hydrogel composites retain their self-supporting capacity and can be printed into 3D structures directly in air and retain their shapes before cross-linking. Then, the whole structures are solidified in situ by applying suitable cross-linking stimuli. The addition of Laponite nanoclay can effectively improve the mechanical and biological properties of hydrogel composites. Specifically, the addition of Laponite nanoclay results in a significant increase in the Young's modulus of each hydrogel-Laponite composite: 1.9-fold increase for the poly(ethylene glycol) diacrylate (PEGDA)-Laponite composite, 7.4-fold increase for the alginate-Laponite composite, and 3.3-fold increase for the gelatin-Laponite composite.
Activation of ERBB2 Signaling Causes Resistance to the EGFR-Directed Therapeutic Antibody Cetuximab (2011)

Cetuximab, an antibody directed against the epidermal growth factor receptor, is an effective clinical therapy for patients with colorectal, head and neck, and non-small cell lung cancer, particularly for those with KRAS and BRAF wild-type cancers. Treatment in all patients is limited eventually by the development of acquired resistance, but little is known about the underlying mechanism. Here, we show that activation of ERBB2 signaling in cell lines, either through ERBB2 amplification or through heregulin up-regulation, leads to persistent extracellular signal-regulated kinase 1/2 signaling and consequently to cetuximab resistance. Inhibition of ERBB2 or disruption of ERBB2/ERBB3 heterodimerization restores cetuximab sensitivity in vitro and in vivo. A subset of colorectal cancer patients who exhibit either de novo or acquired resistance to cetuximab-based therapy has ERBB2 amplification or high levels of circulating heregulin. Collectively, these findings identify two distinct resistance mechanisms, both of which promote aberrant ERBB2 signaling, that mediate cetuximab resistance. Moreover, these results suggest that ERBB2 inhibitors, in combination with cetuximab, represent a rational therapeutic strategy that should be assessed in patients with cetuximab-resistant cancers.
The oncogenic properties of mutant p110α and p110β phosphatidylinositol 3-kinases in human mammary epithelial cells (2005)

The PIK3CA gene encoding the p110alpha subunit of Class IA phosphatidylinositol 3-kinases (PI3Ks) is frequently mutated in human tumors. Mutations in the PIK3CB gene encoding p110beta, the only other widely expressed Class IA PI3K, have not been reported. We compared the biochemical activity and transforming potential of mutant forms of p110alpha and p110beta in a human mammary epithelial cell system. The two most common tumor-derived alleles of p110alpha, H1047R and E545K, potently activated PI3K signaling. Human mammary epithelial cells expressing these alleles grew efficiently in soft agar and as orthotopic tumors in nude mice. We also examined a third class of mutations in p110alpha, those in the p85-binding domain. A representative tumor-derived p85-binding-domain mutant R38H showed modestly reduced p85 binding and weakly activated PI3K/Akt signaling. In contrast, a deletion mutant lacking the entire p85-binding domain efficiently activated PI3K signaling. When we constructed in p110beta a mutation homologous to the E545K allele of p110alpha, the resulting p110beta mutant was only weakly activated and allowed minimal soft-agar growth. However, a gene fusion of p110beta with the membrane anchor from c-Src was highly active and transforming in both soft-agar and orthotopic nude mouse assays. Thus, although introduction of activating mutations from p110alpha at the corresponding sites in p110beta failed to render the enzyme oncogenic in human cells, the possibility remains that other mutations might activate the beta isoform.
Small Intestinal Motility Patterns in the Perinatal Period (1983)

Sucking, Swallowing, Gastric Emptying, and Motility in Infancy and Their Effect on the Mode of Feeding: PDF Only
NANOG Reporter Cell Lines Generated by Gene Targeting in Human Embryonic Stem Cells (2010)

The newly derived NANOG reporter hESC lines present novel tools to visualize NANOG expression in viable hESCs. In future applications, these reporter lines can be used to elucidate the function and regulation of NANOG in pluripotent hESCs.
Molecular Mechanisms of Transmembrane Signaling in B Lymphocytes (1987)

Exhausted CD8 T (Tex) cells are a distinct cell lineage that arise during chronic infections and cancers in animal models and humans. Tex cells are characterized by progressive loss of effector functions, high and sustained inhibitory receptor expression, ...Read More
Thrombin interaction with platelets. Influence of a platelet protease nexin. (1987)

A fraction of the 125I-thrombin that binds to human platelets is taken into a sodium dodecyl sulfate-resistant 77 kDa complex with a platelet factor (Bennett, W. F., and Glenn, K. C. (1980) Cell 22, 621-627). Here we show that this platelet factor is in several respects similar to protease nexin I (PNI), a fibroblast thrombin inhibitor. The complexes are of the appropriate size, bind to Sepharose that has been derivatized with anti-PNI antibody, do not form when the thrombin active site has been blocked with diisopropylphosphofluoridate, and do not appear on platelets when heparin is present. However, the platelet factor does not bind urokinase, indicating that this "platelet PN" may be distinct from PNI. Following brief incubation with 125I-thrombin, platelet PN X 125I X thrombin complexes are found both associated with the platelets and free in the binding medium. 125I-Thrombin has a higher affinity for platelet PN than for platelet receptors. In 30-s binding incubations carried out with thrombin at concentrations below 0.3 nM, formation of the 77-kDa complex accounts for most of the platelet specific binding of 125I-thrombin. Subtracting this large contribution to 125I-thrombin-specific binding reveals that the reversible binding of 125I-thrombin to platelet receptors exhibits sigmoidal thrombin dose-dependence. Thrombin stimulation of platelet [14C]serotonin release exhibits similar thrombin dose dependence. These results indicate that platelets may possess a mechanism for suppressing their interaction with active thrombin at thrombin doses below 0.3 nM. It is possible that platelet PN carries out this function by capturing thrombin before thrombin binds to its signal-transmitting receptors.
Printable programmable viscoelastic materials for robots (2016)

Impact protection and vibration isolation are an important component of the mobile robot designer's toolkit; however, current damping materials are available only in bulk or molded form, requiring manual fabrication steps and restricting material property control. In this paper we demonstrate a new method for 3D printing viscoelastic materials with specified material properties. This method allows arbitrary net-shape material geometries to be rapidly fabricated and enables continuously varying material properties throughout the finished part. This new ability allows robot designers to tailor the properties of viscoelastic damping materials in order to reduce impact forces and isolate vibrations. We present a case study for using this material to create jumping robots with programmed levels of bouncing.
Comparisons and Contrasts of Shale Gas and Tight Gas Developments, North American Experience and Trends (2012)

Abstract All Shale Gas reservoirs are not the same. There are no typical Tight Gas reservoirs. These two statements can be found numerous times in the literature on shale gas and tight gas reservoirs. The one common aspect of developing these unconventional resources is that wells in both must be ‘hydraulically fractured’ in order to produce commercial amounts of gas. Operator challenges and objectives to be accomplished during each phase of the Asset Life Cycle (Exploration, Appraisal, Development, Production, and Rejuvenation) of both shale gas and tight gas are similar. Drilling, well design, completion methods and hydraulic fracturing are somewhat similar; but formation evaluation, reservoir analysis, and some of the production techniques are quite different. Much of the experience in shale and tight gas has been developed in the US and in Canada, to a lesser extent; and most of the technologies that have been developed by operators and service companies are transferable to other parts of the world. However, the infrastructure, including equipment and service company availability, governmental regulations, logistics, processing, environmental considerations, and pricing are not the same as in the US. This may impact the rate of the technology transfer as well as the selection of some of the technology. This paper is focused on operations challenges, technologies, and experience associated with shale and tight gas projects. It is likely that environmental concerns and the drive to reduce development costs of tight and shale gas reservoirs will drive new approaches to the development of these reservoirs in China, Latin America, Middle East, North Africa, and other parts of the world.
Vanadium pentoxide cathode materials for high-performance lithium-ion batteries enabled by a hierarchical nanoflower structure via an electrochemical process (2012)

Hierarchical vanadium oxide nanoflowers (V10O24·nH2O) were synthesized via a simple, high throughput method employing a fast electrochemical reaction of vanadium foil in NaCl aqueous solution, followed by an aging treatment at room temperature. During the electrochemical process, the anodic vanadium foil is dissolved in the form of multi-valence vanadium ions into the solution, driven by the applied electrical field. After being oxidized, the VO2+ and VO2+ ions instantly react with the OH− in the electrolyte to form uniformly distributed vanadium oxide nanoparticles at a high solution temperature due to the exothermic nature of the reaction. Finally, nucleation and growth of one dimensional nanoribbons takes place on the surface of the nanoparticles during the aging process to form unique hierarchical V10O24·nH2O nanoflowers. Upon heat treatment, the hierarchical architecture of the vanadium pentoxide nanoflower morphology is maintained. Such a material provides porous channels, which facilitate fast ion diffusion and effective strain relaxation upon Li ion charge–discharge cycling. The electrochemical tests reveal that the V2O5 nanoflowers cathode could deliver high reversible specific capacities with 100% coulombic efficiency, especially at high C rates (e.g., 140 mAh g−1 at 10 C).
Core−Shell Quantum Dots of Lattice-Matched ZnCdSe2 Shells on InP Cores:  Experiment and Theory (2000)

Lattice-matched ZnCdSe2 concentric epilayer shells up to 50 Å in thickness have been grown on InP core quantum dots (QDs). The quality of the epitaxially grown shells was monitored by absorption and emission spectra and transmission electron microscopy (TEM). Shell growth was shown to be controllable and was consistently accompanied by a large red shift of the absorption and emission spectra. This results from increased electron delocalization and, hence, lower confinement energy compared to core QDs with no shell. Core−shell nanocrystals also show higher quantum yields for emission since the interface of the QDs is better passivated and deep surface trap luminescence is converted into band-edge luminescence. Theoretical calculations of the electron probability density in these core−shell QDs were made using high-level self-consistent field and tight-binding methods; the theoretical results are consistent with the experimental results.
RCY1, an Arabidopsis thaliana RPP8/HRT family resistance gene, conferring resistance to cucumber mosaic virus requires salicylic acid, ethylene and a novel signal transduction mechanism (2002)

The dominant locus, RCY1, in the Arabidopsis thaliana ecotype C24 confers resistance to the yellow strain of cucumber mosaic virus (CMV-Y). The RCY1 locus was mapped to a 150-kb region on chromosome 5. Sequence comparison of this region from C24 and a CMV-Y-susceptible C24 mutant predicts that the RCY1 gene encodes a 104-kDa CC-NBS-LRR-type protein. The RCY1 gene from C24, when expressed in the susceptible ecotype Wassilewskija (Ws), restricted the systemic spread of virus. RCY1 is allelic to the resistance genes RPP8 from the ecotype Landsberg erecta and HRT from the ecotype Dijon-17, which confer resistance to Peronospora parasitica biotype Emco5 and turnip crinkle virus (TCV), respectively. Examination of RCY1 plants defective in salicylic acid (SA), jasmonic acid (JA) and ethylene signaling revealed a requirement for SA and ethylene signaling in mounting a resistance response to CMV-Y. The RCY1 nahG etr1 double mutants exhibited an intermediate level of susceptibility to CMV-Y, compared to the resistant ecotype C24 and the susceptible ecotypes Columbia and Nossen. This suggests that in addition to SA and ethylene, a novel signaling mechanism is associated with the induction of resistance in CMV-Y-infected C24 plants. Moreover, our results suggest that the signaling pathways downstream of the RPP8, HRT, and RCY1 have evolved independently.
Stable Forbidden-Region Virtual Fixtures for Bilateral Telemanipulation (2005)

There has been recent interest in novel human-machine collaborative control laws, called “virtual fixtures,” which provide operator assistance for telemanipulation tasks. A forbidden-region virtual fixture is a constraint, implemented in software, that seeks to prevent the slave manipulator of a master/slave telemanipulation system from entering into a forbidden region of the workspace. In this paper, we consider the problem of unstable vibrations of the slave and/or master against forbidden-region virtual fixtures for a general class of telemanipulator control architectures, including those with haptic feedback. To the best of the authors’ knowledge, there has been no rigorous study of the stability of forbidden-region virtual fixtures in previous work. The system is evaluated around the master and slave equilibrium position resulting from a constant desired human input force, using a discrete state-space model. We present a method to analytically determine if instability is possible in the system. We thoroughly evaluate this method, experimentally, applying malicious user strategies that attempt to drive the system unstable. Our approach agrees with experimental results and can be used to design and analyze the stability and transient properties of a telemanipulator interacting with virtual fixtures. We show that the user can affect both slave- and master-side virtual fixture stability by modifying his or her impedance characteristics. However, the upper bound on stable slave-side virtual fixture stiffness does not depend on the particular user.
SU6668 is a potent antiangiogenic and antitumor agent that induces regression of established tumors. (2000)

Vascular endothelial growth factor, fibroblast growth factor (FGF), and platelet-derived growth factor (PDGF) and their cognate receptor tyrosine kinases are strongly implicated in angiogenesis associated with solid tumors. Using rational drug design coupled with traditional screening technologies, we have discovered SU6668, a novel inhibitor of these receptors. Biochemical kinetic studies using isolated Flk-1, FGF receptor 1, and PDGF receptor beta kinases revealed that SU6668 has competitive inhibitory properties with respect to ATP. Cocrystallographic studies of SU6668 in the catalytic domain of FGF receptor 1 substantiated the adenine mimetic properties of its oxindole core. Molecular modeling of SU6668 in the ATP binding pockets of the FIk-1/KDR and PDGF receptor kinases provided insight to explain the relative potency and selectivity of SU6668 for these receptors. In cellular systems, SU6668 inhibited receptor tyrosine phosphorylation and mitogenesis after stimulation of cells by appropriate ligands. Oral or i.p. administration of SU6668 in athymic mice resulted in significant growth inhibition of a diverse panel of human tumor xenografts of glioma, melanoma, lung, colon, ovarian, and epidermoid origin. Furthermore, intravital multifluorescence videomicroscopy of C6 glioma xenografts in the dorsal skinfold chamber model revealed that SU6668 treatment suppressed tumor angiogenesis. Finally, SU6668 treatment induced striking regression of large established human tumor xenografts. Investigations of SU6668 activity in cancer patients are ongoing in Phase I clinical trials.
Expression of nuclear lamins during mouse preimplantation development (1988)

The expression of nuclear lamins during mouse preimplantation development was studied by immunofluorescence, immunoblotting and immunoprecipitation. Two sera were used, specific either for lamin B or lamins A and C. Both sera gave a positive staining of the nuclear periphery throughout preimplantation development (fertilized eggs to late blastocysts). Immunoblots revealed that the three lamins were present in eggs and blastocysts. However, lamin A from eggs was found to have a higher apparent Mr than lamin A from blastocysts and other mouse cells. Using immunoprecipitation, synthesis of lamin A was detected in eggs while synthesis of lamin B was detected in 8-cell embryos and blastocysts, indicating that at least some of the lamins used during early development do not come from a store in the egg. These results are discussed in relation to the possible role of lamins during cell differentiation.
Scaffold‐free inkjet printing of three‐dimensional zigzag cellular tubes (2012)

The capability to print three-dimensional (3D) cellular tubes is not only a logical first step towards successful organ printing but also a critical indicator of the feasibility of the envisioned organ printing technology. A platform-assisted 3D inkjet bioprinting system has been proposed to fabricate 3D complex constructs such as zigzag tubes. Fibroblast (3T3 cell)-based tubes with an overhang structure have been successfully fabricated using the proposed bioprinting system. The post-printing 3T3 cell viability of printed cellular tubes has been found above 82% (or 93% with the control effect considered) even after a 72-h incubation period using the identified printing conditions for good droplet formation, indicating the promising application of the proposed bioprinting system. Particularly, it is proved that the tubular overhang structure can be scaffold-free fabricated using inkjetting, and the maximum achievable height depends on the inclination angle of the overhang structure. As a proof-of-concept study, the resulting fabrication knowledge helps print tissue-engineered blood vessels with complex geometry.
Induction of humoral and cellular immunity against influenza virus by immunization of newborn mice with a plasmid bearing a hemagglutinin gene (1997)

Neonates and infants display an intrinsic disability to mount protective immune responses to influenza viruses or conventional influenza vaccines. We investigated the ability of naked DNA to prime protective immune responses by inoculating newborn and adult mice with a plasmid (pHA) expressing hemagglutinin (HA) from the neurovirulent strain A/WSN/33 of influenza virus. Continuous exposure to small doses of antigen subsequent to neonatal DNA immunization led to effective priming of specific B and Th cells, rather than tolerance induction. The pHA immunization of adult mice primed a strongly biased Th1 response, whereas in neonates it induced a mixed Th1/Th2 response. In contrast to the effect of live-virus immunization, DNA immunization of neonates was followed by enhanced cytotoxic T lymphocyte responses subsequent to challenge with A/WSN/33 influenza virus. Mice immunized as neonates or adults with pHA plasmid exhibited significant increases in survival and decreases in virus lung titers following lethal challenge with the A/WSN/33 virus or the A/PR8/34 drift variant. Our results demonstrate that DNA vaccination is an efficient and safe means to generate broad humoral and cellular immune responses to influenza viruses, during the earliest stages of postnatal life.
The ECM protein LTBP‐2 is a suppressor of esophageal squamous cell carcinoma tumor formation but higher tumor expression associates with poor patient outcome (2010)

Our previous studies of chromosome 14 transfer into tumorigenic esophageal squamous cell carcinoma (ESCC) cell line, SLMT, suggested the existence of tumor suppressor genes on chromosome 14. Gene expression profiling of microcell hybrids and the tumor segregants identified an interesting gene, LTBP-2 (latent transforming growth factor β binding protein 2), which has been analyzed here for its role in ESCC. LTBP-2 maps to 14q24 and encodes a secreted protein, which is a component of the extracellular matrix microfibrils. LTBP-2 expression was downregulated in ESCC cell lines and tumor tissues. Promoter hypermethylation was found to be involved in LTBP-2 inactivation. Functional studies indicated its tumor-suppressive roles in ESCC. In the in vitro colony formation and Matrigel three-dimensional culture assays, LTBP-2 decreased the colony-forming abilities of ESCC cell lines. LTBP-2 expression was associated with reduction of cell migrating and invasive abilities. LTBP-2 could also reduce the tube-forming ability of endothelial cells. Moreover, LTBP-2 induced tumor suppression in in vivo nude mouse assays. Tissue microarray immunohistochemical staining analysis indicated that LTBP-2 expression is reduced in tumor tissues when compared to normal tissues, and LTBP-2 expression correlated significantly with the survival of ESCC patients. Thus, LTBP-2 appears to play an important role in ESCC.
Further structural studies of the heavy chain of HLA antigens and its similarity to immunoglobulins. (1977)

The papain-solubilized fragment of the heavy chain of HLA-B7, which is the NH2-terminal part of the whole polypeptide chain, can be divided into three regions by mild acid and cyanogen bromide cleavages. The first 100 amino acids terminating in a methionine residue contain the carbohydrate moiety; this segment is followed by two others of molecular weights 9,999 and 13,000, each containing an intrachain disulfide bridge. The two intrachain disulfide bridges are separated by a stretch of amino acids containing an acid-labile aspartyl-prolHLA-2, A28, and AW25 contain this acid-labile peptide bond in their larger subunit. Sequencing from the acid cleavage site of HLA-7 through the third half-cystine revealed consideralbe homology with amino acid sequences around a half-cystine in immunoglobulin variable regions.