gebhart/patrepeval huggingface dataset:
In vitro assay of erythropoietin: Simple determination in a small amount of human serum samples. (1984)

An in vitro method for the determination of erythropoietin (EPO) titres in human serum samples was developed to detect low levels of EPO titres in various haematological states. Fetal mouse liver cells (FMLC) were incubated in methylcellulose-containing media, and radioiron incorporation into haem was estimated in cultured FMLC. We could determine the concentrations of EPO from around 20 to 600 mU per ml of a very small amount of serum samples from patients and normal adults. Using this method, EPO titres of normal adults (54 +/- 31 mU/ml), chronic renal failure patients (29 +/- 23 mU/ml), aplastic anaemia patients (545 +/- 74 mU/ml), and polycythaemia vera patients (16 +/- 7 mU/ml) were determined.
Silicon Nanowires:  Preparation, Device Fabrication, and Transport Properties (2000)

The preparation of 20 ± 5 nm diameter Si nanowires and the electrical characterization of Si nanowire devices are presented. The nanowires were grown at 450−500 °C on solid substrates via the vapor−liquid−solid mechanism using Au or Zn nucleation catalysts and SiH4 as the silicon source. The wires were investigated by high-resolution transmission electron microscopy. Two types of wires were found, as characterized by different growth directions (〈111̄〉 and 〈211〉). Several types of devices, including crossed nanowire devices, four- and six-terminal devices, and three-terminal (gated) devices, were fabricated. For certain devices, various electrode compositions were also studied. The measured resistivity of these nanowires was separated from the contact resistance and could be varied from >105 Ω cm to ∼10-3 Ω cm. The wide variation in resistivity was related to the nature of the electrical contact to the wires (Schottky or Ohmic) and to the doping level of the wires. Doping of the nanowires was performed by the thermal diffusion of metal catalyst into the nanowires at 750−850 °C. Au nucleated nanowires exhibited resistivity values much lower than those of similarly treated Zn nucleated nanowires. This result is attributed to the much larger relative solid solubility of gold in silicon.
Extracellular DNA in Pancreatic Cancer Promotes Cell Invasion and Metastasis (2013)

Aggressive metastasis is the chief cause of the high morbidity and mortality associated with pancreatic cancer, yet the basis for its aggressive behavior remains elusive. Extracellular DNA (exDNA) is a recently discovered component of inflammatory tissue states. Here, we report that exDNA is present on the surface of pancreatic cancer cells where it is critical for driving metastatic behavior. exDNA was abundant on the surface and vicinity of cultured pancreatic cancer cells but absent from normal pancreas cells. Strikingly, treatment of cancer cell cultures with DNase I to degrade DNA nonspecifically reduced metastatic characters associated with matrix attachment, migration, and invasion. We further assessed the role of exDNA in pancreatic cancer metastasis in vivo using an orthotopic xenograft model established by implantation of pancreatic cancer cells expressing firefly luciferase. Noninvasive bioluminescent imaging confirmed that DNase I treatment was sufficient to suppress tumor metastasis. Mechanistic investigations suggested the existence of a positive feedback loop in which exDNA promotes expression of the inflammatory chemokine CXCL8, which leads to higher production of exDNA by pancreatic cancer cells, with a significant reduction in CXCL8 levels achieved by DNase I treatment. Taken together, our results strongly suggest that exDNA contributes to the highly invasive and metastatic character of pancreatic cancer.
Community composition of bacteria co-cultivated with microalgae in non-axenic algal cultures (2009)

by bacterial contamination. Non-axenic algal cultures often need to be purified because physiological, chemical, molecular or taxonomic studies on microalgae usually require axenic cultures (e.g. Stanier et al., 1971; Watanabe et al., 1998). Some aquatic bacteria have been known to cause lysis of algal cells (Cole, 1982), and the removal of such algicidal action is another important reason for purification. In a minority of cases, non-axenic algal cultures can be used for studies of symbiosis and interaction between algae and bacteria. For instance, Watanabe et al. (2005) investigated the associations between a strain of the alga Chlorella solrokiniana IAM C-212 (NIES-2169) and its extracellular symbionts (that is, in a strict sense, contaminating microorganisms isolated from the algal culture), and found a growthpromoting effect of a bacterial and a fungal isolate on the alga. In the present study, we examined bacterial community compositions in non-axenic algal cultures maintained in a culture collection, in order to evaluate their potential usefulness as materials for studies on algal-bacterial associations. Three non-axenic cultures of green microalgae, Chlorella saccharophila NIES-640, Ulothrix variabilis NIES-329 and Volvox aureus NIES-864, were obtained from the Microbial Culture Collection at the National Institute for Environmental Studies (MCC-NIES), Tsukuba, Japan. They were originally isolated in 1987 in Hokkaido, Japan, in 1984 in Ibaraki , Japan, and in 1997 in Brandenburg, Germany, respectively. They had been maintained in the MCC-NIES without purification or cryopreservation before their use in the present study (M. Erata, personal communication). C. saccharophila NIES-640 and U. variabilis NIES329 were cultivated in C medium (Ichimura, 1971), and V. aureus NIES-864 was cultivated in AF-6 medium (Kato, 1982), under a 16:8 light/dark cycle with a light intensity of approximately 20 μmol photons m−2 sec−1 at about 25°C in light and 20°C in dark. DNA extraction, polymerase chain reaction amplification of the V3 region of the 16S rRNA gene (16S rDNA) and denaturing gradient gel electrophoresis (DGGE) of the amplicons, followed by cloning and sequencing of the excised DGGE bands, were performed as described previously (Otsuka et al., 2008a, 2008b). A BLAST search was conducted for homologies to the partial sequences of 16S rDNA obtained (Altschul et al., 1997), and phylogenetic analysis was performed, whenever necessary, as described previously (Otsuka et al., 2008a, 2008b).
An analysis of Memnet—an experiment in high-speed shared-memory local networking (1988)

Memnet is a shared-memory local area network under development at the University of Delaware that provides close coupling to the processors of a physically distributed multiprocessor system. The Memnet local network appears as memory in the physical address space of each processor (host) on the network.
Stable exposure of the coreceptor-binding site in a CD4-independent HIV-1 envelope protein (1999)

We recently derived a CD4-independent virus from HIV-1/IIIB, termed IIIBx, which interacts directly with the chemokine receptor CXCR4 to infect cells. To address the underlying mechanism, a cloned Env from the IIIBx swarm (8x) was used to produce soluble gp120. 8x gp120 bound directly to cells expressing only CXCR4, whereas binding of IIIB gp120 required soluble CD4. Using an optical biosensor, we found that CD4-induced (CD4i) epitopes recognized by mAbs 17b and 48d were more exposed on 8x than on IIIB gp120. The ability of 8x gp120 to bind directly to CXCR4 and to react with mAbs 17b and 48d in the absence of CD4 indicated that this gp120 exists in a partially triggered but stable state in which the conserved coreceptor-binding site in gp120, which overlaps with the 17b epitope, is exposed. Substitution of the 8x V3 loop with that from the R5 virus strain BaL resulted in an Env (8x-V3BaL) that mediated CD4-independent CCR5-dependent virus infection and a gp120 that bound to CCR5 in the absence of CD4. Thus, in a partially triggered Env protein, the V3 loop can change the specificity of coreceptor use but does not alter CD4 independence, indicating that these properties are dissociable. Finally, IIIBx was more sensitive to neutralization by HIV-positive human sera, a variety of anti-IIIB gp120 rabbit sera, and CD4i mAbs than was IIIB. The sensitivity of this virus to neutralization and the stable exposure of a highly conserved region of gp120 suggest new strategies for the development of antibodies and small molecule inhibitors to this functionally important domain.
Bak BH3 Peptides Antagonize Bcl-xL Function and Induce Apoptosis through Cytochrome c-independent Activation of Caspases (1999)

The Bcl-2 homology 3 (BH3) domain is crucial for the death-inducing and dimerization properties of pro-apoptotic members of the Bcl-2 protein family, including Bak, Bax, and Bad. Here we report that synthetic peptides corresponding to the BH3 domain of Bak bind to Bcl-xL, antagonize its anti-apoptotic function, and rapidly induce apoptosis when delivered into intact cells via fusion to the Antennapedia homeoprotein internalization domain. Treatment of HeLa cells with the Antennapedia-BH3 fusion peptide resulted in peptide internalization and induction of apoptosis within 2-3 h, as indicated by caspase activation and subsequent poly(ADP-ribose) polymerase cleavage, as well as morphological characteristics of apoptosis. A point mutation within the BH3 peptide that blocks its ability to bind to Bcl-xL abolished its apoptotic activity, suggesting that interaction of the BH3 peptide with Bcl-2-related death suppressors, such as Bcl-xL, may be critical for its activity in cells. While overexpression of Bcl-xL can block BH3-induced apoptosis, treatment with BH3 peptides resensitized Bcl-xL-expressing cells to Fas-mediated apoptosis. BH3-induced apoptosis was blocked by caspase inhibitors, demonstrating a dependence on caspase activation, but was not accompanied by a dramatic early loss of mitochondrial membrane potential or detectable translocation of cytochrome c from mitochondria to cytosol. These findings demonstrate that the BH3 domain itself is capable of inducing apoptosis in whole cells, possibly by antagonizing the function of Bcl-2-related death suppressors.
Setting the Target for a Better Cervical Screening Test (2000)

In Brief Objective To determine the potential effects on costs and outcomes of changes in sensitivity and specificity with new screening methods for cervical cancer. Methods Using a Markov model of the natural history of cervical cancer, we estimated the effects of sensitivity, specificity, and screening frequency on cost-effectiveness. Our estimates of conventional Papanicolaou test sensitivity of 51% and specificity of 97% were obtained from a meta-analysis. We estimated the effect of reducing false-negative rates from 40–90% and increasing false-positive rates by up to 20%, independently and jointly. We varied the marginal cost of improving sensitivity from $0 to $15. Results When specificity was held constant, increasing sensitivity of the Papanicolaou test increased life expectancy and costs. When sensitivity was held constant, decreasing specificity of the Papanicolaou test increased costs, an effect that was more dramatic at more frequent intervals. Decreased specificity had a substantial effect on cost-effectiveness estimates of improved Papanicolaou test sensitivity. Most of those effects are related to the cost of evaluation and treatment of low-grade lesions. Conclusion Policies or technologies that increased sensitivity of cervical cytologic screening increased overall costs, even if the cost of the technology was identical to that of conventional Papanicolaou smears. These effects appear to be caused by relatively high prevalence of low-grade lesions and are magnified at frequent screening intervals. Efficient cervical cancer screening requires methods with greater ability to detect lesions that are most likely to become cancerous. Improving the sensitivity of conventional Papanicolaou tests with no improvement in specificity increases costs to cervical cancer prevention programs.
Enhanced endothelialization and microvessel formation in polyester grafts seeded with CD34+ bone marrow cells (2000)

The authors have shown accelerated endothelialization on polyethylene terephthalate (PET) grafts preclotted with autologous bone marrow. Bone marrow cells have a subset of early progenitor cells that express the CD34 antigen on their surfaces. A recent in vitro study has shown that CD34(+) cells can differentiate into endothelial cells. The current study was designed to determine whether CD34(+) progenitor cells would enhance vascular graft healing in a canine model. The authors used composite grafts implanted in the dog's descending thoracic aorta (DTA) for 4 weeks. The 8-mm x 12-cm composite grafts had a 4-cm PET graft in the center and 4-cm standard ePTFE grafts at each end. The entire composite was coated with silicone rubber to make it impervious; thus, the PET segment was shielded from perigraft and pannus ingrowth. There were 5 study grafts and 5 control grafts. On the day before surgery, 120 mL bone marrow was aspirated, and CD34(+) cells were enriched using an immunomagnetic bead technique, yielding an average of 11.4 +/- 5. 3 x 10(6). During surgery, these cells were mixed with venous blood and seeded onto the PET segment of composite study grafts; the control grafts were treated with venous blood only. Hematoxylin and eosin, immunocytochemical, and AgNO(3 )staining demonstrated significant increases of surface endothelialization on the seeded grafts (92% +/- 3.4% vs 26.6% +/- 7.6%; P =.0001) with markedly increased microvessels in the neointima, graft wall, and external area compared with controls. In dogs, CD34(+) cell seeding enhances vascular graft endothelialization; this suggests practical therapeutic applications. (Blood. 2000;95:581-585)
Compared With Dietary Monounsaturated and Saturated Fat, Polyunsaturated Fat Protects African Green Monkeys From Coronary Artery Atherosclerosis (1995)

Atherogenic diets enriched in saturated, n-6 polyunsaturated, and monounsaturated fatty acids were fed to African green monkeys for 5 years to define effects on plasma lipoproteins and coronary artery atherosclerosis. The monkeys fed polyunsaturated and monounsaturated fat had similar plasma concentrations of LDL cholesterol, and these values were significantly lower than for LDL in the animals fed saturated fat. Plasma HDL cholesterol concentrations were comparable in animals fed saturated and monounsaturated fat and were significantly higher than in animals fed polyunsaturated fat. Thus, the monounsaturated fat group had the lowest LDL/HDL ratio. LDL particle size was largest in the saturated and monounsaturated fat groups, significantly larger than in the polyunsaturated fat group. LDL particle enrichment with cholesteryl oleate was the greatest in the animals fed monounsaturated fat, next greatest in the saturated fat-fed animals, and was least in the polyunsaturated fat-fed animals. Coronary artery atherosclerosis as measured by intimal area was less in the polyunsaturated fat compared with the saturated fat groups, was less in the animals fed polyunsaturated fat compared with the monounsaturated fat-fed animals, but did not differ between the monounsaturated and saturated fat groups. Cholesteryl ester, particularly cholesteryl oleate, accumulation in the coronary arteries was also similar between groups fed monounsaturated and saturated fat but was minimal in the animals fed polyunsaturated fat. In sum, the monkeys fed monounsaturated fat developed equivalent amounts of coronary artery atherosclerosis as those fed saturated fat, but monkeys fed polyunsaturated fat developed less. The beneficial effects of the lower LDL and higher HDL in the animals fed monounsaturated fat apparently were offset by the atherogenic shifts in LDL particle composition. Dietary polyunsaturated fat appears to result in the least amount of coronary artery atherosclerosis because it prevents cholesteryl oleate accumulation in LDL and the coronary arteries in these primates.
ChemInform Abstract: Selective Reduction of Acid Chloride with a Catalytic Amount of an Indium Compound. (2000)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Human xenograft models as useful tools to assess the potential of novel therapeutics in prostate cancer (2008)

With docetaxel as effective chemotherapy for hormone refractory prostate cancer (HRPC), the number of new treatment combinations for HRPC is expanding demanding a fast-track screening system. This review elaborates on the use of xenograft models to select the most promising combination therapies for entering into phase II clinical trials.
Binding of TCR Multimers and a TCR-Like Antibody with Distinct Fine-Specificities Is Dependent on the Surface Density of HLA Complexes (2012)

Class I Major Histocompatibility Complex (MHC) molecules evolved to sample degraded protein fragments from the interior of the cell, and to display them at the surface for immune surveillance by CD8(+) T cells. The ability of these lymphocytes to identify immunogenic peptide-MHC (pMHC) products on, for example, infected hepatocytes, and to subsequently eliminate those cells, is crucial for the control of hepatitis B virus (HBV). Various protein scaffolds have been designed to recapitulate the specific recognition of presented antigens with the aim to be exploited both diagnostically (e.g. to visualize cells exposed to infectious agents or cellular transformation) and therapeutically (e.g. for the delivery of drugs to compromised cells). In line with this, we report the construction of a soluble tetrameric form of an αβ T cell receptor (TCR) specific for the HBV epitope Env(183-191) restricted by HLA-A*02:01, and compare its avidity and fine-specificity with a TCR-like monoclonal antibody generated against the same HLA target. A flow cytometry-based assay with streptavidin-coated beads loaded with Env(183-191)/HLA-A*02:01 complexes at high surface density, enabled us to probe the specific interaction of these molecules with their cognate pMHC. We demonstrate that the TCR tetramer has similar avidity for the pMHC as the antibody, but they differ in their fine-specificity, with only the TCR tetramer being capable of binding both natural variants of the Env(183-191) epitope found in HBV genotypes A/C/D (187Arg) and genotype B (187Lys). Collectively, the results highlight the promiscuity of our soluble TCR, which could be an advantageous feature when targeting cells infected with a mutation-prone virus, but that binding of the soluble oligomeric TCR relies considerably on the surface density of the presented antigen.
Human B cells express IL-5 receptor messenger ribonucleic acid and respond to IL-5 with enhanced IgM production after mitogenic stimulation with Moraxella catarrhalis (1996)

The potential for IL-5 to regulate human B cells is controversial despite its well established role as a regulatory factor for murine B cells. We hypothesized that the mechanism by which human B cells were stimulated would, as with murine B cells, determine their potential to respond to IL-5. Since Staphylococcus aureus Cowan strain I (SAC) and Moraxella catarrhalis (MCat) stimulate human B cells by distinct interactions with cell-surface Ig, we compared their potential to induce an IL-5-responsive state by human B cells purified to homogeneity. Neither SAC alone nor SAC plus IL-5 stimulated Ig production, although microgram quantities of IgM were produced with SAC plus IL-2. In contrast, MCat induced microgram quantities of IgM by B cells in the absence of exogenous cytokines, and IL-5 significantly increased IgM production over twofold in the majority of donors. Synergism of IL-5 and IL-2 was detected using suboptimal concentrations of IL-2 with MCat-, but not SAC-, stimulated B cells. Donor B cells unresponsive to IL-5 when stimulated with MCat, became IL-5 responsive in the presence of IL-2. Since message for the IL-5R alpha, IL-5R beta, and soluble IL-5R alpha chains was detected in freshly isolated B cells, we further investigated whether IL-5 responsiveness to MCat, but not SAC, was due to their differential regulation of IL-5R mRNA. Surprisingly, stimulation by either MCat or SAC, without or with IL-2, increased both IL-5R alpha and IL-5R beta mRNA and decreased soluble IL-5R alpha mRNA. These studies demonstrate that, as with murine B cells, human B cells express message for IL-5R but can respond to IL-5 only if appropriately stimulated to undergo terminal differentiation.
Blood progenitor cell separation from clinical leukapheresis product by magnetic nanoparticle binding and magnetophoresis (2006)

Positive selection of CD34+ blood progenitor cells from circulation has been reported to improve patient recovery in applications of autologous transplantation. Current magnetic separation methods rely on cell capture and release on solid supports rather than sorting from flowing suspensions, which limits the range of therapeutic applications and the process scale up. We tested CD34+ cell immunomagnetic labeling and isolation from fresh leukocyte fraction of peripheral blood (leukapheresis) using the continuous quadrupole magnetic flow sorter (QMS), consisting of a flow channel (SHOT, Greenville, IN) and a quadrupole magnet with a maximum field intensity (B(o)) of 1.42 T and a mean force field strength (S(m)) of 1.45 x 10(8) TA/m(2). Both the sample magnetophoretic mobility (m) and the inlet and outlet flow patterns highly affect the QMS performance. Seven commercial progenitor cell labeling reagent combinations were quantitatively evaluated by measuring magnetophoretic mobility of a high CD34 expression cell line, KG-1a, using the cell tracking velocimeter (CTV). The CD34 Progenitor Cell Isolation Kit (Miltenyi Biotec, Bergisch Gladbach, Germany) showed the strongest labeling of KG-1a cells and was selected for progenitor cell enrichment from 11 fresh and 11 cryopreserved clinical leukapheresis samples derived from different donors. The CD34+ cells were isolated with a purity of 60-96%, a recovery of 18-60%, an enrichment rate of 12-169, and a throughput of (1.7-9.3) x 10(4) cells/s. The results also showed a highly regular dependence of the QMS performance on the flow conditions that agreed with the theoretical predictions based on the CD34+ cell magnetophoretic mobility.
The safe and effective use of fowlpox virus as a vector for poultry vaccines. (1994)

The safety and efficacy of a fowlpox-Newcastle disease vaccine were evaluated by in vitro and in vivo methods. Genetic and phenotypic stability following cell culture and chick passage were demonstrated. The safety characteristics of the recombinant virus equalled or exceeded those of the parent fowlpox virus, as determined by lack of shed and spread to contacts, failure to revert to virulence following passage in chicks and innocuity in other avian species. The fowlpox-Newcastle Disease virus effectively immunized against virulent fowlpox challenge and virulent Newcastle disease challenge (intramuscular or intra-ocular administration). These results indicate that the recombinant FPV/NDV virus is a safe and effective vaccine for poultry.