WorldWideScience
1

Overexpression of human virus surface glycoprotein precursors induces cytosolic unfolded protein response in Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

BackgroundThe expression of human virus surface proteins, as well as other mammalian glycoproteins, is much more efficient in cells of higher eukaryotes rather than yeasts. The limitations...Full Text Available

2

The DFNA5 gene, responsible for hearing loss and involved in cancer, encodes a novel apoptosis-inducing protein  

British Library Electronic Table of Contents (United Kingdom)

DFNA5 was first identified as a gene causing autosomal dominant hearing loss (HL). Different mutations have been found, all exerting a highly specific gain-of-function effect, in which skipping of exon 8 causes the HL. Later reports revealed the involvement of the gene in different types of cancer. Epigenetic silencing of DFNA5 in a large percentage of gastric, colorectal and breast tumors and p53-dependent transcriptional activity have been reported, concluding that DFNA5 acts as a tumor suppressor gene in different frequent types of cancer. Despite these data, the molecular function of DFNA5 has not been investigated properly. Previous transfection studies with mutant DFNA5 in yeast and in mammalian cells showed a toxic effect of the mutant protein, which was not seen after transfection ...

2011-01-01

4

The mammalian oocyte orchestrates the rate of ovarian follicular development  

UK PubMed Central (United Kingdom)

The development of both the mammalian oocyte and the somatic cell compartments of the ovarian follicle is highly coordinated; this coordination ensures that the ovulated oocyte is ready to undergo fertilization...Full Text Available

2002-03-05

5

Mammalian Sirtuins and Energy Metabolism  

UK PubMed Central (United Kingdom)

Sirtuins are highly conserved NAD+-dependent protein deacetylases and/or ADP-ribosyltransferases that can extend the lifespan of several lower model organisms including yeast, worms and flies....Full Text Available

6

Functions of mammalian Cdc7 kinase in initiation/monitoring of DNA replication and development  

Energy Technology Data Exchange (ETDEWEB)

Cdc7 kinase plays an essential role in firing of replication origins by phosphorylating components of the replication complexes. Cdc7 kinase has also been implicated in S phase checkpoint signaling downstream of the ATR and Chk1 kinases. Inactivation of Cdc7 in yeast results in arrest of cell growth with 1C DNA content after completion of the ongoing DNA replication. In contrast, conditional inactivation of Cdc7 in undifferentiated mouse embryonic stem (ES) cells leads to growth arrest with rapid cessation of DNA synthesis, suggesting requirement of Cdc7 functions for continuation of ongoing DNA synthesis. Furthermore, loss of Cdc7 function induces recombinational repair (nuclear Rad51 foci) and G2/M checkpoint responses (inhibition of Cdc2 kinase). Eventually, p53 becomes highly activated and the cells undergo massive p53-dependent apoptosis. Thus, defective origin activation in ...

2003-11-27

7

Modular coherence of protein dynamics in yeast cell polarity system  

UK PubMed Central (United Kingdom)

In this study, we investigated on a systems level how complex protein interactions underlying cell polarity in yeast determine the dynamic association of proteins with the polar cortical domain (PCD)...Full Text Available

2011-05-03

9

Flow microfluorometric and spectrophotofluorometric analysis of DNA staining in mammalian cells  

Science.gov (United States)

The effects of various fixative agents, pH, ionic strength, stain concentration, and magnesium concentration on DNA staining with the antibiotics olivomycin, chromomycin A3, and mithramycin were examined with DNA in solution and in mammalian cells.

1977-01-01

10

Circulating Skeletal Stem Cells  

UK PubMed Central (United Kingdom)

We report the isolation of adherent, clonogenic, fibroblast-like cells with osteogenic and adipogenic potential from the blood of four mammalian species. These cells phenotypically resemble but are...Full Text Available

2001-05-28

11

Antagonistic Gcn5-Hda1 interactions revealed by mutations to the Anaphase Promoting Complex in yeast  

UK PubMed Central (United Kingdom)

BackgroundHistone post-translational modifications are critical for gene expression and cell viability. A broad spectrum of histone lysine residues have been identified in yeast...Full Text Available

12

Genetical approach to oxygen toxicity. [Saccharomyces cerevisiae  

Energy Technology Data Exchange (ETDEWEB)

The role of intermediate products of dioxygen reduction in cytotoxic effects ascribed to oxygen molecules was studied in vivo using various yeast mutants with changed response to oxygen stress. It has been documented that superoxide radical exerts its deleterious effects on yeast cells directly and the role of other oxygen species derived from it is hardly detectable. Yeast Saccharomyces cerevisiae, however, cannot be considered as a typical eukaryotic organism due to its inability of synthesizing polyunsaturated fatty acids (pufa). These fatty acids are known as main target molecules during oxidative stress and their peroxidation leads to cytotoxic effects. As fatty acid content could be easily manipulated in yeast, this organism was used to evaluate the contribution of pufa peroxidation process to the cytotoxic effects of oxygen. Results obtained show, that ...

1986-01-01

13

DNA synthesis inhibition in mammalian cells as a test for mutagenic carcinogens  

Science.gov (United States)

Current models of DNA repair of biological damage are reviewed correlating the similarity between carcinogenesis and mutagenesis theories. (PCS)

1979-01-01

14

An intact microtubule cytoskeleton is not needed for cell cycle progression if the preceding mitosis is of normal duration  

UK PubMed Central (United Kingdom)

SummaryFor mammalian somatic cells the importance of microtubule cytoskeleton integrity in interphase cell cycle progression is uncertain. The loss, diminishment, or stabilization...Full Text Available

2007-12-04

15

A piggyBac transposon-based genome-wide library of insertionally mutated Blm-deficient murine ES cells  

UK PubMed Central (United Kingdom)

Cultured mouse or human embryonic stem (ES) cells provide access to all of the genes required to elaborate the fundamental components and physiological systems of a mammalian cell. Chemical or insertional...Full Text Available

2009-04-01

16

The wavelength dependence of ultraviolet enhanced reactivation in a mammalian cell-virus system  

International Nuclear Information System (INIS)

The effect of UV radiation in the wavelength region 230 nm to 302 nm on the ability of an irradiated mammalian cell to reactivate UV-irradiated mammalian virus was tested. An action spectrum for radiation enhanced reactivation (RER) is presented. The shape of the action spectrum points to a combined nucleic acid-protein target for UV radiation effects on this cellular parameter. An analysis of the results of others involving the biochemical and photobiological events involved in RER does not allow us to distinguish which macromolecule is the major contributor to this effect. Studies involving an analogous phenomenon in bacteris (Weigle reactivation) imply that RER and WR amy involve similar mechanisms. (author).

17

Removal of lead from solution using non-living residual brewery yeast  

Energy Technology Data Exchange (ETDEWEB)

A number of preparations of residual non-living brewery yeast were examined for their ability to remove lead from solution. Those preparations included washed and un-washed intact yeast and washed and un-washed homogenates of the yeast cells. Using biosorption isotherm analysis it was found that the washed and un-washed preparations of intact, non-living yeast exhibited maximum biosorption capacities for lead of 127 and 99 mg/g dry weight biomass, respectively. The washed and un-washed cell homogenates exhibited maximum biosorption capacities of 38 and 139 mg lead/g dry weight biomass, respectively. Since it had previously been shown that these preparations of biomass were capable of removing uranium from solution by combined biosorption and precipitation processes, it was decided to examine removal of lead from solution using a form of equilibrium dialysis in ...

1998-10-01

18

Scyl1 Facilitates Nuclear tRNA Export in Mammalian Cells by Acting at the Nuclear Pore Complex  

UK PubMed Central (United Kingdom)

Scyl1 is an evolutionarily conserved N-terminal protein kinase-like domain protein that plays a role in COP1-mediated retrograde protein trafficking in mammalian cells. Furthermore, loss of Scyl1 function...Full Text Available

2010-07-15

19

Cloning and Analysis of a Candida albicans Gene That Affects Cell Surface Hydrophobicity  

UK PubMed Central (United Kingdom)

The opportunistic pathogenic yeast Candida albicans exhibits growth phase-dependent changes in cell surface hydrophobicity, which has been correlated with adhesion to host tissues....Full Text Available

2001-06-01

20

Cell-mediated mutagenesis and cell transformation of mammalian cells by chemical carcinogens. [Rats, hamsters  

Science.gov (United States)

We have developed a cell-mediated mutagenesis assay in which cells with the appropriate markers for mutagenesis are co-cultivated with either lethally irradiated rodent embryonic cells that can metabolize carcinogenic hydrocarbons or with primary rat liver cells that can metabolize chemicals carcinogenic to the liver. During co-cultivation, the reactive metabolites of the procarcinogen appear to be transmitted to the mutable cells and induce mutations in them. Assays of this type make it possible to demonstrate a relationship between carcinogenic potency of the chemicals and their ability to induce mutations in mammalian cells. In addition, by simultaneously comparing the frequencies of transformation and mutation induced in normal diploid hamster cells by benzo(a)pyrene (BP) and one of its metabolites, it is possible to ...

1977-01-01

21

The oncogenic transforming potential of the passage of single ? particles through mammalian cell nuclei  

UK PubMed Central (United Kingdom)

Domestic, low-level exposure to radon gas is considered a major environmental lung-cancer hazard involving DNA damage to bronchial cells by α particles from radon progeny. At domestic exposure...Full Text Available

1999-01-05

22

Nuclear reprogramming in mammalian somatic cell nuclear cloning  

UK PubMed Central (United Kingdom)

Nuclear cloning is still a developing technique used to create genetically identical animals by somatic cell nuclear transfer into unfertilized eggs. Despite an intensive effort in a number...Full Text Available

2004-01-01

23

Mechanism of cell death resulting from DNA interstrand cross-linking in mammalian cells  

UK PubMed Central (United Kingdom)

DNA interstrand cross-links (ICLs) are critical cytotoxic lesions produced by cancer chemotherapeutic agents such as the nitrogen mustards and platinum drugs; however, the exact mechanism of ICL-induced...Full Text Available

2011-08-01

24

Differentiation of trophoblast stem cells into giant cells is triggered by p57/Kip2 inhibition of CDK1 activity  

UK PubMed Central (United Kingdom)

Genome endoreduplication during mammalian development is a rare event for which the mechanism is unknown. It first appears when fibroblast growth factor 4 (FGF4) deprivation induces differentiation...Full Text Available

2008-11-01

25

Kes1p shares homology with human oxysterol binding protein and participates in a novel regulatory pathway for yeast Golgi-derived transport vesicle biogenesis.  

UK PubMed Central (United Kingdom)

The yeast phosphatidylinositol transfer protein (Sec14p) is required for biogenesis of Golgi-derived transport vesicles and cell viability, and this essential Sec14p requirement is abrogated by inactivation...Full Text Available

1996-12-02

26

Cell cultures are more sensitive than Saccharamoyces cervisiae tests for assessing the toxicity of aquatic pollutants  

Energy Technology Data Exchange (ETDEWEB)

Cultured fish and human cells have been used as bioassay systems for the evaluation of the toxicity of aquatic pollutants. Numerous assays using bacteria and yeast have also been used for such purposes. The authors report the toxicity of aquatic pollutants (Cd, Hg, and Ni), using cell culture systems and the yeast Saccharomyces cervisiae test. Cd, Hg, and Ni were chosen as model compounds of pollutants because the related toxicity is now fairly well established.

1988-07-01

27

Morphologie des cellules de levure et la reproduction sexuelle - Apercu general et quelques considerations  

British Library Electronic Table of Contents (United Kingdom)

Over the decades, basic research in life sciences has profited greatly from the study of the small unicellular fungal species Saccharomyces cerevisiae. This yeast turned out to be key for the identification and understanding of molecular mechanisms that underlay the basic functions of all eukaryotic cells. These include, but are not limited to, the regulatory mechanisms behind cellular reproduction (cell cycle control), cellular morphogenesis (cell polarity, cytoskeleton and membrane trafficking) and the management of cellular information (chromosome biology, transcription and translation). Rapid access to genomic information of many yeast species, combined with bioinformatics analyses, provide information on the evolutionary history of yeasts and the molecular ancestry of their constituen...

2011-01-01

28

The requirement of yeast replication origins for pre-replication complex proteins is modulated by transcription  

UK PubMed Central (United Kingdom)

The mini-chromosome maintenance proteins Mcm2–7 are essential for DNA replication. They are loaded onto replication origins during G1 phase of the cell cycle to form a pre-replication complex...Full Text Available

2005-01-01

29

PtdIns 3-Kinase Orchestrates Autophagosome Formation in Yeast  

UK PubMed Central (United Kingdom)

Eukaryotic cells can massively transport their own cytoplasmic contents into a lytic compartment, the vacuole/lysosome, for recycling through a conserved system called autophagy. The key process in...Full Text Available

2011-01-01

30

Nuclear Pore Complex Number and Distribution throughout the Saccharomyces cerevisiae Cell Cycle by Three-Dimensional Reconstruction from Electron Micrographs of Nuclear Envelopes  

UK PubMed Central (United Kingdom)

The number of nuclear pore complexes (NPCs) in individual nuclei of the yeast Saccharomyces cerevisiae was determined by computer-aided reconstruction of entire nuclei from electron...Full Text Available

1997-11-01

31

Mitochondrial transmission during mating in Saccharomyces cerevisiae is determined by mitochondrial fusion and fission and the intramitochondrial segregation of mitochondrial DNA.  

UK PubMed Central (United Kingdom)

To gain insight into the process of mitochondrial transmission in yeast, we directly labeled mitochondrial proteins and mitochondrial DNA (mtDNA) and observed their fate after the fusion of two cells....Full Text Available

1997-07-01

32

Insights into Cdc13 dependent telomere length regulation  

UK PubMed Central (United Kingdom)

Cdc13 is a single stranded telomere binding protein that specifically localizes to the telomere ends of budding yeasts and is essential for cell viability. It caps the ends of chromosomes thus preventing...Full Text Available

33

piggyBac is a flexible and highly active transposon as compared to Sleeping Beauty, Tol2, and Mos1 in mammalian cells  

UK PubMed Central (United Kingdom)

A nonviral vector for highly efficient site-specific integration would be desirable for many applications in transgenesis, including gene therapy. In this study we directly compared the genomic integration...Full Text Available

2006-10-10

34

Use of Forward Genetics to Discover Novel Regulators of NF-?B  

UK PubMed Central (United Kingdom)

Forward and reverse genetic experiments have both played important roles in revealing critical aspects of mammalian signal transduction pathways in cell culture experiments. Only recently have we begun...Full Text Available

2010-06-01

35

Real-time monitoring of circadian clock oscillations in primary cultures of mammalian cells using Tol2 transposon-mediated gene transfer strategy  

UK PubMed Central (United Kingdom)

BackgroundThe circadian rhythm in mammals is orchestrated by a central pacemaker in the brain, but most peripheral tissues contain their own intrinsic circadian oscillators. The...Full Text Available

36

Mesenchymal cell re-modeling during mouse secondary palate re-orientation  

UK PubMed Central (United Kingdom)

The formation of mammalian secondary palate requires a series of developmental events such as growth, elevation and fusion. Despite recent advances in the field of palate development, the process...Full Text Available

2010-07-01

37

Large-scale Analysis of Thermo-stable, Mammalian Proteins Provides Insights into the Intrinsically Disordered Proteome  

UK PubMed Central (United Kingdom)

Intrinsically disordered proteins are predicted to be highly abundant and play broad biological roles in eukaryotic cells. In particular, by virtue of their structural malleability and propensity...Full Text Available

2009-01-01

38

Evaluation of 13C isotopic tracers for metabolic flux analysis in mammalian cells  

UK PubMed Central (United Kingdom)

13C metabolic flux analysis (MFA) is the most comprehensive means of characterizing cellular metabolic states. Uniquely labeled isotopic tracers enable more focused analyses to probe...Full Text Available

2009-11-01

39

Cytochrome c-d regulates developmental apoptosis in the Drosophila retina  

UK PubMed Central (United Kingdom)

The role of cytochrome c (Cyt c) in caspase activation has largely been established from mammalian cell-culture studies, but much remains to be learned about its physiological...Full Text Available

2006-09-01

40

Bif-1 regulates Atg9 trafficking by mediating the fission of Golgi membranes during autophagy  

UK PubMed Central (United Kingdom)

Atg9 is a transmembrane protein essential for autophagy which cycles between the Golgi network, late endosomes and LC3-positive autophagosomes in mammalian cells during starvation through a mechanism...Full Text Available

2011-01-01

41

Antiviral Inhibition of Enveloped Virus Release by Tetherin/BST-2: Action and Counteraction  

UK PubMed Central (United Kingdom)

Tetherin (BST2/CD317) has been recently recognized as a potent interferon-induced antiviral molecule that inhibits the release of diverse mammalian enveloped virus particles from infected cells. By...Full Text Available

42

Expression of bacterial luciferase in eukaryotic cells  

International Nuclear Information System (INIS)

Expression of Bacterial luciferase enzyme (lux) in mammalian cells would be a powerful bioreporter protein system for in vivo imaging because eukaryotic luciferases need expensive substrates. However, only a few efforts have been made to express bacterial luciferase enzyme in mammalian cells. As the result of this, we attempted to construct bicistronic vector including two bacterial luciferase genes (LuxA and LuxB) for assessing the potential to be visualized in vitro or in vivo by optical imaging system after transfection to mammalian cells. We designed and synthesized luxA and luxB genes from Photorhabdus Luminescens. To co-express both luxA and luxB genes from a single promoter, we cloned as a bicistronic transcript fused with an internal ribosomal entry site (IRES). This bicistronic transcript was transfected by Superfect to HEK 293T ...

2005-11-18

43

Molecular, functional and structural properties of the prolyl oligopeptidase of Trypanosoma cruzi (POP Tc80), which is required for parasite entry into mammalian cells  

UK PubMed Central (United Kingdom)

We have demonstrated that the 80 kDa POP Tc80 (prolyl oligopeptidase of Trypanosoma cruzi) is involved in the process of cell invasion, since specific inhibitors block parasite...Full Text Available

2005-05-15

44

The k43 gene, required for chorion gene amplification and diploid cell chromosome replication, encodes the Drosophila homolog of yeast origin recognition complex subunit 2  

UK PubMed Central (United Kingdom)

Lethal alleles of the Drosophila k43 gene result in small or missing imaginal discs, greatly reduced mitotic index, and fragmented and abnormally condensed chromosomes. A female-sterile...Full Text Available

1997-04-15

45

Specific requirement of the chromatin modifier mSin3B in cell cycle exit and cellular differentiation  

UK PubMed Central (United Kingdom)

The Sin3-histone deacetylase (HDAC) corepressor complex is conserved from yeast to humans. Mammals possess two highly related Sin3 proteins, mSin3A and mSin3B, which serve as scaffolds tethering HDAC...Full Text Available

2008-03-18

46

SWI/SNF and Asf1 Independently Promote Derepression of the DNA Damage Response Genes under Conditions of Replication Stress  

UK PubMed Central (United Kingdom)

The histone chaperone Asf1 and the chromatin remodeler SWI/SNF have been separately implicated in derepression of the DNA damage response (DDR) genes in yeast cells treated with genotoxins that cause...Full Text Available

47

Primary organization of nucleosomal core particles is invariable in repressed and active nuclei from animal, plant and yeast cells.  

UK PubMed Central (United Kingdom)

A refined map for the linear arrangement of histones along DNA in nucleosomal core particles has been determined by DNA-protein crosslinking. On one strand of 145-bp core DNA, histones are aligned in...Full Text Available

1985-05-24

48

Mutations in cyr1 and pat1 reveal pheromone-induced G1 arrest in the fission yeast Schizosaccharomyces pombe  

DEFF Research Database (Denmark)

Investigations into sexual differentiation and pheromone response in the fission yeast Schizosaccharomyces pombe are complicated by the need to first starve the cells of nitrogen. Most mating-related experiments are therefore performed on non-dividing cells. Here we overcome this problem by using two mutants that bypass the nutritional requirements and respond to the M-factor mating pheromone in rich medium. The first mutant lacks the cyr1 gene which encodes adenylate cyclase and these cells contain no measurable amounts of cAMP. When M-factor is added to a growing h+ cyr1- strain it causes a transient G1 arrest of cell division, transcription of mat1-Pm, and elongation of the cells to form shmoos. The second mutant contains the temperature-sensitive pat1-114 allele. At 30 degrees C this mutant was previously shown not only to bypass the nutritional signal but ...

1994-01-01

49

Influence of chromatin molecular changes on RNA synthesis during embryonic development  

International Nuclear Information System (INIS)

Two aspects of the chromatin repeat length (r_l) are discussed: (i) Why is r_l longer for slowly dividing cells than in rapidly dividing cells?, and (ii) Why is the temporal evolution of r_l a decreasing function of time (t) in mammalian cortical neurons whereas it is an increasing function of t for granule cells around the time of birth? These questions are discussed in terms of a hypothesis which assumes a correlation between deoxyribonucleic acid (DNA) packaging, transcription, and replication. (author). 27 refs.

50

A mechanistic understanding of production instability in CHO cell lines expressing recombinant monoclonal antibodies  

British Library Electronic Table of Contents (United Kingdom)

Abstract One of the most significant problems in industrial bioprocessing of recombinant proteins using engineered mammalian cells is the phenomenon of cell line instability, where a production cell line suffers a loss of specific productivity (qP). This phenomenon occurs with unpredictable kinetics and has been widely observed in Chinese hamster ovary (CHO) cell lines and with all commonly used gene expression systems. The underlying causes (both genetic and physiological) and the precise molecular mechanisms underpinning cell line instability have yet to be fully elucidated, although recombinant gene silencing and loss of recombinant gene copies have been shown to cause qP loss. In this work we have investigated the molecular mechanisms underpinning qP instability over long-term sub-cult...

2011-01-01

51

Mary Lyon and the hypothesis of random X chromosome inactivation  

British Library Electronic Table of Contents (United Kingdom)

The 50th anniversary of Mary Lyon?s 1961 Nature paper, proposing random inactivation in early embryonic life of one of the two X chromosomes in the cells of mammalian females, provides an opportunity to remember and celebrate the work of those involved. While the hypothesis was initially put forward by Lyon based on findings in the mouse, it was founded on earlier studies, notably the work of Susumu Ohno; it was also suggested independently by Beutler and colleagues using experimental evidence from a human X-linked disorder, glucose-6-phosphate dehydrogenase deficiency, and has proved to be of as great importance for human and medical genetics as it has for general mammalian genetics. Alongside the hypothesis itself, previous cytological studies of mouse and human chromosomes, and the obse...

2011-01-01

52

Loss of cell components during rehydration of dried Rhodotorula glutinis and its implications for lead uptake  

British Library Electronic Table of Contents (United Kingdom)

Abstract Microbial cells are routinely dried and ground before they are used in metal biosorption studies. In this work, a metal biosorbent was prepared by drying biomass of the yeast Rhodotorula glutinis in an oven at 70C for 24-h followed by grinding. Two forms of the prepared biosorbent particles, washed and unwashed, were examined for their ability to remove lead from solution. It was found that the unwashed biosorbent exhibited higher lead uptake than the washed biosorbent. Analysis of the supernatant of washed cells incubated in water and that of unwashed cells incubated in lead solution revealed the presence of protein, carbohydrates, organic acids and inorganic phosphate. Overall, the washed and unwashed cells leached, respectively, 14.5 and 13.4% of their initial dry weight (100-m...

2011-01-01

53

Maintenance and regulation of extracellular volume and the ion environment in Drosophila larval nerves.  

Science.gov (United States)

In mammals and insects, paracellular blood barriers isolate the nervous system from the rest of the animal. Glia and accessory cells of the nervous system use pumps, channels, cotransporters, and exchangers collectively to maintain the extracellular ion environment and osmotic balance in the nervous system. At present, the molecular mechanisms that regulate this process remain unclear. In humans, loss of extracellular ion and volume regulation in the nervous system poses serious health threats. Drosophila is a model genetic organism with a proven track record for uncovering molecular mechanisms relevant to human health and disease. Here, we review what is known about extracellular ion and volume regulation in larval abdominal nerves, present some new data about the impact of neural activity on the extracellular environment, and relate the findings to mammalian systems. Homologies have been found at the level of morphology, physiology, molecular ...

2011-02-08

54

Fundamental aspects of the freezing of cells, with emphasis on mammalian ova and embryos. (Aspectos fundamentales de la congelacion de celulas, especialmente ovulos y embriones de mamiferos  

Energy Technology Data Exchange (ETDEWEB)

For most cells there exists an optimum cooling rate. Both supraoptimal rates and suboptimal rates can be very damaging. The optimal rate varies enormously from less than or equal to 1/sup 0/C/min for mammalian preimplantation embryos to greater than or equal to 800/sup 0/C/min for the human red cell. Death at supraoptimal rates is the result of the formation of intracellular ice and its recrystallization during warming. Intracellular ice occurs when cells are cooled too rapidly to allow them to equilibrate by the osmotic withdrawal of intracellular water. The definition of too rapid depends chiefly on the size of the cell and its permeability to water. Death at suboptimal rates is a consequence of the major alterations in aqueous solutions produced by ice formation. The chief effects are a major reduction in the fraction of the solution remaining unfrozen at a given temperature and ...

1980-01-01

55

Molecular evolution and characterization of fungal indoleamine 2,3-dioxygenases.  

Science.gov (United States)

Indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) are tryptophan-degrading enzymes. Mammalian IDO expression is induced by cytokines and has antimicrobial and immunomodulatory effects. A major role of mammalian TDO is to supply nicotinamide adenine dinucleotide (NAD(+)). In fungi, the IDO homologue is thought to be expressed constitutively and supply NAD(+), as TDO is absent from their genomes. Here, we reveal the distribution of IDO genes among fungal species and characterize their enzymatic activity. The yeast, Saccharomyces cerevisiae has only one IDO gene, whereas the koji-mold, Aspergillus oryzae has two genes, IDO? and IDO?. The A. oryzae IDO? showed more similar enzymatic properties to those of S. cerevisiae IDO than IDO?, suggesting that the A. oryzae IDO? is a functional homologue of the S. cerevisiae IDO. From the IDO? gene, two isoforms, IDO? and IDO?(+) could be generated by alternative ...

2010-12-18

56

Extreme sensitivity of some intestinal crypt cells to X and #gamma# irradiation  

International Nuclear Information System (INIS)

Reference is made to Cheng and Leblond (Amer. J. Anat.; 141:537 (1974)) who used tritiated thymidine to kill cells synthesising DNA in the crypts of the small intestine. Amongst their findings was that very low doses caused measurable cell killing and that the killing was not random throughout the crypt but occurred selectively at the crypt base where stem cells are presumably located. It is here reported that the presence of hypersensitive cells at the base of the crypts can be demonstrated after whole-body X- or gamma-irradiation, and the time sequence for the production and loss of the killed cells is described together with their dose-response relationship. The studies were conducted on mice. The data were expressed as surviving rather than killed cells, and it was established that the crypt are amongst the most sensitive of mammalian ...

1977-10-01

57

Relationship of DNA repair processes to mutagenesis and carcinogenesis in mammalian cells. Progress report, November 1, 1979-October 31, 1980  

International Nuclear Information System (INIS)

The objective of this research is to determine the role of DNA repair in mutagenesis and carcinogenesis in mammalian cells. Use of the host-cell reactivation viral suicide enrichment procedure was initiated in the isolation of repair-deficient mutants. Lightly mutagenized BHK cells were infected with irradiated Herpes simplex virus (HSV); several radiation-sensitive strains were isolated among the survivors of the infection. The characterization of these strains is progressing and the enrichments are continuing. That alterations in the frequency of mutation of C3H/10T 1/2 cells, occurring as a result of holding the cells in a confluent state following treatment with ethylmethane sulfonate, parallel the alterations in the frequency of neoplastic transformation was found. The repair capabilities of BHK cells were found to be intermediate in ...

58

Transforming Growth Factor-b Induces Differentiation of the Labyrinthine Trophoblast Stem Cell Line SM10  

British Library Electronic Table of Contents (United Kingdom)

The mammalian placenta consists of different trophoblast cell types that assist in the variety of functions required for the maintenance of pregnancy. In rodents, labyrinthine trophoblasts of the placenta are especially important, because they are capable of differentiating into fused labyrinthine cells, which form the feto-maternal exchange surface. Even though the molecular signals triggering labyrinthine trophoblast differentiation are poorly understood, transforming growth factor-b (TGF-b) has been shown to be present in the placental environment and alter trophoblast development. In this study, we investigated the effects of TGF-b on the differentiation of the labyrinthine trophoblast stem cell lines SM10 and HRP-1. RT-PCR analyses demonstrated that while the molecular expression of l...

2005-01-01

59

T cell receptor beta chain from sea bream (Sparus aurata): Molecular cloning, expression and modelling of the complexes with MHC class I  

British Library Electronic Table of Contents (United Kingdom)

The T cell receptor is a fundamental mediator of the adaptive immune responses, since TR ab on T cells recognize foreign structures (peptides derived from processed antigens) bound to the major histocompatibility complex (MHC) on APC cells. In the present study, we report the cloning of six TRB chains cDNA sequences from gilthead sea bream (Sparus aurata), a fish of high economical impact in South Mediterranean aquaculture. The V-BETA domains have the canonical features of known teleost and mammalian TR V-BETA domains and have been divided in four different subgroups. A multiple alignment of the six sea bream TRB chains with other known TRB sequences was assembled and showed the conservation of the four cysteine residues involved in disulphide bonds and of some amino acids with an importan...

2008-01-01

60

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

Energy Technology Data Exchange (ETDEWEB)

The biodegradation of ring-/sup 14/C- and methyl-/sup 14/C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO/sub 2/. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

1985-05-01

61

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

International Nuclear Information System (INIS)

The biodegradation of ring-"1"4C- and methyl-"1"4C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO_2. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

62

Cloning and expression of a human kidney cDNA for an /alpha//sub 2/-adrenergic receptor subtype  

Energy Technology Data Exchange (ETDEWEB)

An /alpha//sub 2/-adrenergic receptor subtype has been cloned from a human kidney cDNA library using the gene for the human platelet /alpha//sub 2/-adrenergic receptor as a probe. The deduced amino acid sequence resembles the human platelet /alpha//sub 2/-adrenergic receptor and is consistent with the structure of other members of he family of guanine nucleotide-binding protein-coupled receptors. The cDNA was expressed in a mammalian cell line (COS-7), and the /alpha//sub 2/-adrenergic ligand (/sup 3/H)rauwolscine was bound. Competition curve analysis with a variety of adrenergic ligands suggests that this cDNA clone represents the /alpha//sub 2/B-adrenergic receptor. The gene for this receptor is on human chromosome 4, whereas the gene for the human platelet /alpha//sub 2/-adrenergic receptor (/alpha//sub 2/A) lies on chromosome 10. This ability to express the receptor in mammalian cells, free of other ...

1988-09-01

63

In vitro differentiation of rat embryonic stem cells into functional cardiomyocytes  

British Library Electronic Table of Contents (United Kingdom)

The recent breakthrough in the generation of rat embryonic stem cells (rESCs) opens the door to application of gene targeting to create models for the study of human diseases. In addition, the in vitro differentiation system from rESCs into derivatives of three germ layers will serve as a powerful tool and resource for the investigation of mammalian development, cell function, tissue repair, and drug discovery. However, these uses have been limited by the difficulty of in vitro differentiation. The aims of this study were to establish an in vitro differentiation system from rESCs and to investigate whether rESCs are capable of forming terminal-differentiated cardiomyocytes. Using newly established rESCs, we found that embryoid body (EB)-based method used in mouse ESC (mESC) differentiation...

2011-01-01

64

Identification of a functional nuclear export signal in the green fluorescent protein asFP499  

International Nuclear Information System (INIS)

The green fluorescent protein (GFP) asFP499 from Anemonia sulcata is a distant homologue of the GFP from Aequorea victoria. We cloned the asFP499 gene into a mammalian expression vector and showed that this protein was expressed in the human lymphoblast cell line Ramos RA1 and in the embryonic kidney 293T cell line (HEK 293T). In HEK 293T cells, asFP499 was localized mainly in the cytoplasm, suggesting that the protein was excluded from the nucleus. We identified _1_9_4LRMEKLNI_2_0_1 as a candidate nuclear export signal in asFP499 and mutated the isoleucine at position 201 to an alanine. Unlike the wildtype form, the mutant protein was distributed throughout the cytoplasm and nucleus. This is First report of a GFP that contains a functional NES.

2006-04-21

65

Overview of macroautophagy regulation in mammalian cells  

British Library Electronic Table of Contents (United Kingdom)

Macroautophagy is a multistep, vacuolar, degradation pathway terminating in the lysosomal compartment, and it is of fundamental importance in tissue homeostasis. In this review, we consider macroautophagy in the light of recent advances in our understanding of the formation of autophagosomes, which are double-membrane-bound vacuoles that sequester cytoplasmic cargos and deliver them to lysosomes. In most cases, this final step is preceded by a maturation step during which autophagosomes interact with the endocytic pathway. The discovery of AuTophaGy-related genes has greatly increased our knowledge about the mechanism responsible for autophagosome formation, and there has also been progress in the understanding of molecular aspects of autophagosome maturation. Finally, the regulation of au...

2010-01-01

66

Survival of Genetically Modified and Self-Cloned Strains of Commercial Baker's Yeast in Simulated Natural Environments: Environmental Risk Assessment  

UK PubMed Central (United Kingdom)

Although genetic engineering techniques for baker's yeast might improve the yeast's fermentation characteristics, the lack of scientific data on the survival of such strains in natural environments...Full Text Available

2005-11-01

67

Comparison of the Survival and Metabolic Activity of Psychrophilic and Mesophilic Yeasts Subjected to Freeze-Thaw Stress  

UK PubMed Central (United Kingdom)

A mesophilic yeast, Candida utilis, and a psychrophilic yeast, Leucosporidium stokesii, were subjected to freeze-thaw cycling over the range 25 to -60 C. Viability...Full Text Available

1975-06-01

68

Inhibitor of DNA synthesis is present in normal chicken serum  

Energy Technology Data Exchange (ETDEWEB)

The authors have found that heat-inactivated serum (57/sup 0/C for 1 hour) from normal chickens reduces the proliferation of mitogen-stimulated chicken and murine splenocytes as well as some transformed mammalian lymphoblastoid cell lines. Greater than a 50% reduction in /sup 3/H-thymidine incorporation was observed when concanavalin A (Con A)-activated chicken splenocytes that were cultured in the presence of 10% autologous or heterologous serum were compared to mitogen-stimulated cells cultured in the absence of serum. Normal chicken serum (10%) also caused greater than 95% suppression of /sup 3/H-thymidine incorporation by bovine (EBL-1 and BL-3) and gibbon ape (MLA 144) transformed lymphoblastoid cell lines. The only cell line tested that was not inhibited by chicken serum was an IL-2-dependent, murine cell line. Chicken serum also inhibited both /sup ...

1986-03-05

69

Mitochondrial genetic damage induced in yeast by a photoactivated furocoumarin in combination with ethidium bromide or ultraviolet light  

International Nuclear Information System (INIS)

Ethidium bromide (EB) and ultraviolet light (UV) in combination are known to produce a synergistic induction of 'petite' mutants in yeast. Two other agents were combined with EB, 3-Carbethoxypsoralene (3 CPs) activated by 365 nm light or #gamma# rays. EB in combination with 3 CPs also resulted in an enhanced production of 'petite' mutants. After the photoaddition of 3 CPs in exponential phase cells, recovery of the 'petite' mutation during dark liquid holding was inhibited by the presence of EB producing an enhanced number of 'petite' mutants. The behavior of mitochondrial antibiotic resistance markers after individual and combined treatments with EB and 3 CPs indicates a random loss of markers after EB and a preferential loss of a certain region for the 3 CPs photoaddition. The combination of the two agents leads to an additivity of total drug marker losses rather than a synergistic loss. The combination of EB with #gamma# rays produced no ...

70

Reactive biomolecular divergence in genetically altered yeast cells and isolated mitochondria as measured by biocavity laser spectroscopy : a rapid diagnostic method for studying cellular responses to stress and disease.  

Energy Technology Data Exchange (ETDEWEB)

We report an analysis of four strains of baker's yeast (Saccharomyces cerevisiae) using biocavity laser spectroscopy. The four strains are grouped in two pairs (wild type and altered), in which one strain differs genetically at a single locus, affecting mitochondrial function. In one pair, the wild-type rho+ and a rho0 strain differ by complete removal of mitochondrial DNA (mtDNA). In the second pair, the wild-type rho+ and a rho- strain differ by knock-out of the nuclear gene encoding Cox4, an essential subunit of cytochrome c oxidase. The biocavity laser is used to measure the biophysical optic parameter Deltalambda, a laser wavelength shift relating to the optical density of cell or mitochondria that uniquely reflects its size and biomolecular composition. As such, Deltalambda is a powerful parameter that rapidly interrogates the biomolecular state of single cells and mitochondria. Wild-type ...

2006-12-01

71

Global Transcriptional Responses of Fission Yeast to Environmental Stress  

UK PubMed Central (United Kingdom)

We explored transcriptional responses of the fission yeast Schizosaccharomyces pombe to various environmental stresses. DNA microarrays were used to characterize changes in expression...Full Text Available

2003-01-01

72

Apoptosis at Inflection Point in Liquid Culture of Budding Yeasts  

UK PubMed Central (United Kingdom)

Budding yeasts are highly suitable for aging studies, because the number of bud scars (stage) proportionally correlates with age. Its maximum stages are known ...Full Text Available

73

Amphiphysin (Amph) maps to the proximal region of mouse chromosome 13  

Energy Technology Data Exchange (ETDEWEB)

Amphiphysin is a protein concentrated in neuronal synapses and peripherally associated with neurotransmitter vesicles. It is expressed in many neurons of the central and peripheral nervous systems, in the adrenal medulla, in the anterior and posterior pituitary, in cell lines of the endocrine pancreas, and in spermatocytes. Its subcellular localization and tissue distribution indicate a potential involvement in mechanisms of regulated exocytosis. A role in the dynamic organization of the membrane-associated cytoskeleton is suggested by structural homology to the products of two yeast genes, RVS161 and RVS167, whose mutation results in an abnormal actin distribution, disturbs budding morphology, and impairs cell entry into stationary phase. Limited stretches of sequence similarity, including an SH3 domain, are also shared with other actin-binding proteins. Amphiphysin is the dominant autoantigen in paraneoplastic Stiff-Man ...

1995-07-20

74

Effects of microwaves on cell survival at elevated temperatures  

Energy Technology Data Exchange (ETDEWEB)

Since microwaves are used in human cancer therapy, information on specific biological effects of microwaves at elevated temperatures is important. To help supply this information, we exposed mammalian cells (CHO) and bacteria (Serratia marcescens) to hyperthermal temperatures (43, 44, and 45/sup o/C for CHO and 48, 49, and 50/sup o/C for the bacteria) with and without microwave irradiation. Temperature control was maintained by a refrigeration-reheat system and high-velocity water recirculation. The 2450-MHz microwave source was operated in a pulsed mode with power density up to 500 mW/cm/sup 2/. As expected, the survival curve slopes for both cell types increased rapidly with temperature, doubling for each degree Celsius. Microwave irradiation produced no significant change in extrapolation number for either cell type. However, survival curves of CHO cells which received microwaves ...

1981-12-01

75

Characterization of mammalian glucose transport proteins using photoaffinity labeling techniques  

Energy Technology Data Exchange (ETDEWEB)

A carrier-free radioiodinated phenylazide derivative of forskolin, 3-iodo-4-azidophenethylamido-7-O-succinyl-deacetyl-forskolin (({sup 125}I)IAPS-forskolin), has been shown to be a highly selective photoaffinity probe for the human erythrocyte glucose transported and the glucose transport proteins found in several mammalian tissues and cultured cells where the glucose transport protein is present at a low concentration. The photoincorporation of ({sup 125}I)IAPS-forskolin into these glucose transporters was blocked by D- (but not L-) glucose, cytochalasin B, and forskolin. In addition to labeling the mammalian glucose transport proteins, ({sup 125}I)IAPS-forskolin also labeled the L-arabinose transporter from E. coli. In muscle and adipose tissues, glucose transport is markedly increased in response to insulin. ({sup 125}I)IAPS-forskolin was shown to selectivity tag the glucose transporter in membranes derived from these ...

1989-01-01

76

Characterization of mammalian glucose transport proteins using photoaffinity labeling techniques  

International Nuclear Information System (INIS)

A carrier-free radioiodinated phenylazide derivative of forskolin, 3-iodo-4-azidophenethylamido-7-O-succinyl-deacetyl-forskolin (["1"2"5I]IAPS-forskolin), has been shown to be a highly selective photoaffinity probe for the human erythrocyte glucose transported and the glucose transport proteins found in several mammalian tissues and cultured cells where the glucose transport protein is present at a low concentration. The photoincorporation of ["1"2"5I]IAPS-forskolin into these glucose transporters was blocked by D- (but not L-) glucose, cytochalasin B, and forskolin. In addition to labeling the mammalian glucose transport proteins, ["1"2"5I]IAPS-forskolin also labeled the L-arabinose transporter from E. coli. In muscle and adipose tissues, glucose transport is markedly increased in response to insulin. ["1"2"5I]IAPS-forskolin was shown to selectivity tag the glucose transporter in membranes derived from these ...

77

Novel Techniques and Their Wide Applications to Health Foods, Medical and Agricultural Biotechnology in Relation to Policy Making on Genetically Modified Crops and Foods  

CERN Document Server

Selected applications of novel techniques in Agricultural Biotechnology, Health Food formulations and Medical Biotechnology are being reviewed with the aim of unraveling future developments and policy changes that are likely to open new markets for Biotechnology and prevent the shrinking or closing of existing ones. Amongst the selected novel techniques with applications in both Agricultural and Medical Biotechnology are: immobilized bacterial cells and enzymes, microencapsulation and liposome production, genetic manipulation of microorganisms, development of novel vaccines from plants, epigenomics of mammalian cells and organisms, and biocomputational tools for molecular modeling related to disease and Bioinformatics. Both fundamental and applied aspects of the emerging new techniques are being discussed in relation to their anticipated, marked impact on future markets and present policy changes that are needed for success ...

2004-01-01

78

Biological radiation effects  

International Nuclear Information System (INIS)

The stages of processes leading to radiation damage are studied, as well as, the direct and indirect mechanics of its production. The radiation effects on nucleic acid and protein macro moleculas are treated. The physical and chemical factors that modify radiosensibility are analysed, in particular the oxygen effects, the sensibilization by analogues of nitrogen bases, post-effects, chemical protection and inherent cell factors. Consideration is given to restoration processes by excision of injured fragments, the bloching of the excision restoration processes, the restoration of lesions caused by ionizing radiations and to the restoration by genetic recombination. Referring to somatic effects of radiation, the early ones and the acute syndrome of radiation are discussed. The difference of radiosensibility observed in mammalian cells and main observable alterations in tissues and organs are commented. Referring to delayed ...

1976-01-01

79

Mice as a Mammalian Model for Research on the Genetics of Aging  

UK PubMed Central (United Kingdom)

Mice are an ideal mammalian model for studying the genetics of aging: considerable resources are available, the generation time is short, and the environment can be easily controlled, an important...Full Text Available

2011-02-08

80

Transcription Factor IIA t Is Associated with Undifferentiated Cells and Its Gene Expression Is Repressed in Primary Neurons at the Chromatin Level In Vivo  

British Library Electronic Table of Contents (United Kingdom)

The levels of General Transcription Factor (TF) IIA were examined during mammalian brain development and in rat embryo fibroblasts and transformed cell lines. The large TFIIA subunit paralogues ab and t are largely produced in unsynchronized cell lines, yet only TFIIA ab is observed in a number of differentiated tissue extracts. Steady-state protein levels of the TFIIA t, ab, and g subunits were significantly reduced when human embryonal (ec) and hepatic carcinoma cell lines were stimulated to differentiate with either all-trans-retinoic acid (ATRA) or sodium butyrate. ATRA-treated NT2-ec cells required replating to induce a neuronal phenotype and loss of detectable TFIIA t and g proteins. High levels of TFIIA t, ab, and g and Sp factors were identified in extracts from human fetal and rat...

2006-01-01

81

Honokiol-mediated inhibition of PI3K/mTOR pathway: a potential strategy to overcome immunoresistance in glioma, breast, and prostate carcinoma without impacting T cell function.  

Science.gov (United States)

Inhibition of the phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathway is an appealing method for decreasing the immunoresistance and augmenting T cell-mediated immunotherapy. A major impediment to this strategy is the impact of conventional PI3K/mTOR pathway inhibitors on T cell function. In particular, rapamycin, is a well-known immunosuppressant that can decrease the activity of the PI3K/mTOR pathway in tumor cells, but also has a profound inhibitory effect on T cells. Here we show that Honokiol, a natural dietary product isolated from an extract of seed cones from Magnolia grandiflora, can decrease PI3K/mTOR pathway-mediated immunoresistance of glioma, breast and prostate cancer cell lines, without affecting critical proinflammatory T cell functions. Specifically, we show that at doses sufficient to down-regulate ...

85

Evaluation of heavy-metal ion toxicity in fish cells using a combined stress protein and cytotoxicity assay  

Energy Technology Data Exchange (ETDEWEB)

All organisms, from bacteria and yeast to humans, respond to physical and chemical stressors by increasing the synthesis of a small group of cellular stress proteins.'' The authors have developed a simple in vitro system for quickly screening environmentally relevant stressors to detect stress-induced proteins that are good candidates for biomarkers. Polyacrylamide gel electrophoresis was used to detect stressor-induced, concentration-dependent changes in cellular stress protein levels in two fish cell culture systems, whereas simultaneous in vitro neutral red uptake cytotoxicity assays measured the stressors effect on cellular physiology. There was a direct concentration-dependent relationship between sublethal cytotoxic effects and the increases in stress protein levels. Increases of 50 to 200% were detected in stress proteins from desert topminnow, Poeciliopsis lucida, hepatoma-derived cell cultures ...

1994-08-01

86

Human type I pituitary adenylate cyclase activating polypeptide receptor (ADCYAP1R): Localization to chromosome band 7p14 and integration into the cytogenetic, physical, and genetic map of chromosome 7  

Energy Technology Data Exchange (ETDEWEB)

The gene encoding the human type I pituitary adenylate cyclase activating polypeptide receptor (ADCYAP1R1) was mapped to chromosome 7 by PCR analysis of genomic DNA from a human/rodent somatic cell hybrid mapping panel. This assignment was confirmed and the gene localized to chromosome band 7p14 by fluorescence in situ hybridization. A yeast artificial chromosome containing ADCYAP1R1 was identified in the CEPH {open_quotes}B{close_quotes} Mega-YAC library. This YAC includes two highly polymorphic dinucleotide repeat sequences that will facilitate genetic studies of the contribution of ADCYAP1R1 in disease states of the central nervous and neuroendocrine systems. 13 refs., 1 fig.

1994-10-01

87

Chromosomal localization and structure of the human type II IMP dehydrogenase gene  

Energy Technology Data Exchange (ETDEWEB)

We determined the chromosomal localization and structure of the gene encoding human type II inosine 5{prime}-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205), an enzyme associated with cellular proliferation, malignant transformation, and differentiation. Using polymerase chain reaction (PCR) primers specific for type II IMPDH, we screened a panel of human-Chinese hamster cell somatic hybrids and a separate deletion panel of chromosome 3 hybrids and localized the gene to 3p21.1{yields}p24.2. Two overlapping yeast artificial chromosome clones containing the full gene for type II IMPDH were isolated and a physical map of 117 kb of human genomic DNA in this region of chromosome 3 was constructed. The gene for type II IMPDH was localized and oriented on this map and found to span no more than 12.5 kb.

1994-05-01

88

Spark decomposition of SF/sub 6/  

Energy Technology Data Exchange (ETDEWEB)

Gas-insulated systems employing SF/sub 6/ are utilized in a variety of applications in power delivery systems. Because electric arcs, sparks or corona can decompose SF/sub 6/ into by-products having chemical properties different from SF/sub 6/, environmental concerns arise regarding inadvertent human exposures to electrically-decomposed SF/sub 6/. Biological assays in our laboratory using mammalian cell culture systems have revealed that SF/sub 6/, spark-decomposed under specific experimental conditions, can produce cell death. Chemical analysis of spark-decomposed SF/sub 6/ has identified the major decomposition pathways and by-products. Biological testing of individual by-products or by-product mixtures has indicated that these major decomposition products may not account for the majority of the cell killing effects seen in our assays. Further experiments have suggested that S/sub 2/F/sub 10/ may be ...

1989-07-01

89

Biological effects of exogenous adenosine 5 prime -triphosphate on cultured mammalian cells: Evidence for a receptor mechanism and its regulation by desensitization  

Energy Technology Data Exchange (ETDEWEB)

Exogenous adenosine 5{prime}-triphosphate (ATP) mobilized intracellular calcium in human carcinoma A43l cells and in Swiss 3T3 and 3T6 mouse fibroblasts by increasing inositol trisphosphate similar to well down growth factors (platelet-derived growth factor (PDGF), epidermal growth factor (EGF), bradykinin (BK), serum). Calcium mobilization was examined by video imaging of fura-2 fluorescence is single cells, following the radioactive isotope {sup 45}Ca, and monitoring the decrease in fluorescence of cells loaded with chlortetracycline. Uridine 5{prime}-triphosphate, but not other nucleotides, mimicked ATP. Single-cell analysis revealed synchronous responses in 10 sec to ATP, BK or serum, while PDGF (3T3) and EGF (A431) produced slower signals with significant cell-to-cell variation. PDGF desensitized 3T3 cells to ATP and BK added 100 sec later but ATP or BK did ...

1989-01-01

90

Oral administration of circulating precursors for membrane phosphatides can promote the synthesis of new brain synapses  

British Library Electronic Table of Contents (United Kingdom)

Although cognitive performance in humans and experimental animals can be improved by administering omega-3 fatty acid docosahexaenoic acid (DHA), the neurochemical mechanisms underlying this effect remain uncertain. In general, nutrients or drugs that modify brain function or behavior do so by affecting synaptic transmission, usually by changing the quantities of particular neurotransmitters present within synaptic clefts or by acting directly on neurotransmitter receptors or signal-transduction molecules. We find that DHA also affects synaptic transmission in mammalian brain. Brain cells of gerbils or rats receiving this fatty acid manifest increased levels of phosphatides and of specific presynaptic or postsynaptic proteins. They also exhibit increased numbers of dendritic spines on post...

2008-01-01

91

Inhibition of heat shock protein 27 (HspB1) tumorigenic functions by peptide aptamers  

British Library Electronic Table of Contents (United Kingdom)

Human heat shock protein 27 (Hsp27, HspB1) is an anti-apoptotic protein characterized for its tumorigenic and metastatic properties, and now referenced as a major therapeutic target in many types of cancer. Hsp27 biochemical properties rely on a structural oligomeric and dynamic organization. Downregulation by small interfering RNA or inhibition with dominant-negative mutant have proven their efficiency to counteract the anti-apoptotic and protective properties of Hsp27. In this study, we report the isolation and characterization of Hsp27-targeted molecules interfering with its structural organization. Using the peptide aptamer (PA) strategy, we isolated PAs that specifically interact with Hsp27 and not with the other members of the small heat shock protein family. In mammalian cell cultur...

2011-01-01

92

An assessment of health impacts of electrical power transmission lines  

International Nuclear Information System (INIS)

The types of investigations undertaken to test for possible biological effects of extremely low frequency electric fields have been numerous. However, neither animal and plant experimentation nor clinical studies nor experience with operating extremely high voltage transmission lines have to date provided convincing evidence of a harmful effect from exposure to electric fields associated with transmission lines in spite of numerous attempts to find such effects. Analysis of internal fields and currents supports these observations as the levels appear to be too low to affect mammalian cells. Thus, while one can never prove the negative (i.e. that there is no effect), the overwhelming body of evidence indicates that the electric fields associated with high-voltage lines have no deleterious biological effects. (author).

1981-06-26

93

Amino acid substitution: its use in detection and analysis of genetic variants  

International Nuclear Information System (INIS)

Techniques of chemical analysis, amino acid sequencing and autoradiography are being used to study the frequency of incorporation of normally noncoded amino acids into hemoglobins and seminal fluid proteins. We are studying, by the sequencing of radiolabeled proteins followed by the recovery of ["3H] isoleucine phenylthiohydantoin by high-performance liquid chromatography, the frequency at which normally noncoded isoleucine is incorporated into hemoglobin because of base-substitution mutations versus translational errors. Irradiation increases the isoleucine content of human hemoglobin and the frequency of substitution of isoleucine for specific amino acids in rabbit hemoglobin. Studies to date indicate that these techniques have been developed sufficiently for initial analysis of the potential of drugs and environmental pollutants to induce base-substitution mutations in mammalian somatic cells.

94

Effect of vasopressin on ependymal and capillary permeability to tritiated water in cat  

Energy Technology Data Exchange (ETDEWEB)

Ependymal cells line the cerebral ventricles forming the interface that separates the cerebrospinal (CSF) and interstitial fluids (ISF). Extracellular molecules move between ependymal cells, whereas lipid soluble molecules pass both between and through cells. We measured the transfer of tritiated water (TOH) from CSF to blood across the ependymal and capillary interfaces by ventriculocisternal (VC) steady-state tissue clearance. Adult cats anesthetized with pentobarbital sodium underwent VC perfusion with the extracellular marker (/sup 14/C)sucrose and TOH added to the artificial CSF. Brain tissue was analyzed for depth of penetration of the isotopes into periventricular gray matter. We found that TOH distribution space was lower than expected from water content measurements, whereas sucrose space was normal. Using VC steady-state equations we calculated an ependymal permeability that was similar to the permeability of the ...

1986-09-01

95

3-Methyl-3-deazaadenine, a stable isostere of N3-methyl-adenine, is efficiently bypassed by replication in vivo and by transcription in vitro.  

Science.gov (United States)

The goal of the present work was to determine the impact of N3-methyladenine (3-mA), an important lesion generated by many environmental agents and anticancer drugs, on in vivo DNA replication and in vitro RNA transcription. Due to 3-mA chemical instability, the stable isostere 3-methyl-3-deazaadenine (3-m-c(3)A) was site specifically positioned into an oligodeoxynucleotide. The oligomer was, then incorporated into a vector system that is rapidly converted to ssDNA inside yeast cells and requires DNA replication opposite the lesion for plasmid clonal selection. For control purposes, an adenine or a stable apurinic/apyrimidinic (AP)-lesion was placed at the same site. The presence of each lesion in the oligonucleotide was confirmed by MALDI-TOF analysis. Plasmids were then transfected into yeast cells. While the AP-site dramatically reduced plasmid replication in all strains, the 3-m-c(3)A had a slight ...

2011-06-14

96

METABOLIC REGULATION OF ADENOSINE TRIPHOSPHATE SULFURYLASE IN YEAST  

UK PubMed Central (United Kingdom)

de Vito, Peter C. (Princeton University, Princeton, N.J.), and Jacques Dreyfuss. Metabolic regulation of adenosine triphosphate sulfurylase in yeast. J. Bacteriol. 88:1341–1348....Full Text Available

1964-11-01

97

In vivo expression and mitochondrial targeting of yeast apoiso-1-cytochrome c fusion proteins.  

UK PubMed Central (United Kingdom)

To define the import pathway for apoiso-1-cytochrome c in vivo, the coding region for bacterial chloramphenicol acetyltransferase (CAT) or yeast copper metallothionein (CuMT) was fused to the carboxy...Full Text Available

1990-11-01

98

Heavy metals alter the electrokinetic properties of bacteria, yeasts, and clay minerals.  

UK PubMed Central (United Kingdom)

The electrokinetic patterns of four bacterial species (Bacillus subtilis, Bacillus megaterium, Pseudomonas aeruginosa, and Agrobacterium radiobacter), two yeasts (Saccharomyces cerevisiae and Candida...Full Text Available

1992-05-01

99

Evaluation of Acyl Coenzyme A Oxidase (Aox) Isozyme Function in the n-Alkane-Assimilating Yeast Yarrowia lipolytica  

UK PubMed Central (United Kingdom)

We have identified five acyl coenzyme A (CoA) oxidase isozymes (Aox1 through Aox5) in the n-alkane-assimilating yeast Yarrowia lipolytica, encoded by the POX1...Full Text Available

1999-09-01

100

A Novel Function of the DNA Repair Gene rhp6 in Mating-Type Silencing by Chromatin Remodeling in Fission Yeast  

UK PubMed Central (United Kingdom)

Recent studies have indicated that the DNA replication machinery is coupled to silencing of mating-type loci in the budding yeast Saccharomyces cerevisiae, and a similar silencing mechanism...Full Text Available

1998-09-01

101

Studies on the biosorption of uranium by a thermotolerant, ethanol-producing strain of Kluyveromyces marxianus  

Energy Technology Data Exchange (ETDEWEB)

The ability of residual biomass from the thermotolerant ethanol-producing yeast strain Kluyveromyces marxianus IMB3 to function as a biosorbent for uranium has been examined. It was found that the biomass had an observed maximum biosorption capacity of 120 mg U/g dry weight of biomass. The calculated value for the biosorption maximum, obtained by fitting the data to the Langmuir model was found to be 130 mg U/g dry weight biomass. Maximum biosorption capacities were examined at a number of temperatures and both the observed and calculated values obtained for those capacities increased with increasing temperature. Decreasing the pH of the biosorbate solution resulted in a decrease in uptake capacity. When biosorption reactions were carried out using sea-water as the diluent it was found that the maximum biosorption capacity of the biomass increased significantly. Using transmission electron microscopy, uranium crystals were shown to be concentrated on the outer ...

1997-06-01

102

Molecular studies of the uncoupling protein  

Energy Technology Data Exchange (ETDEWEB)

The uncoupling protein (UCP) is a proton/anion transporter found in the inner mitochondrial membrane of brown adipocyte. Although UCP has nor been detected in mitochondria from any other tissue, it shares structural and catalytic properties with several other mitochondrial carrier proteins. Although UCP was discovered only recently it is one of the most extensively studied mitochondrial carrier proteins.More recently, the mouse, rat, and human genes encoding for UCP have been isolated and sequenced. The availability of these various tools has led to several significant observations. UCP gene expression is strongly controlled at the level of transcription by signals that are activated after the stimulation of brown adipocytes by norepinephrine. The comparison of UCP gene with the genes encoding the adenine nucleotide translocator revealed the existence of structural and evolutionary homologies. Moreover, in humans the UCP gene and one form of adenine nucleotide translocator gene are ...

1991-06-01

103

Cholera toxin binding sites in yeast triggers biochemical pathway  

International Nuclear Information System (INIS)

... e Biologia Molecular (SBBq), Sao Paulo, SP (Brazil) 217 p. APPLIED LIFE

1998-05-23

104

Characterization of commercially available selenized yeast food supplements  

International Nuclear Information System (INIS)

... Rome (Italy) Istituto Superiore di Sanita (Italy) 207 p. ENVIRONMENTAL

2009-04-01

105

Effect of UV radiation on the killer phenotype in the wine yeast-saccharomycetes and spontaneous variation of this character  

International Nuclear Information System (INIS)

Spontaneous and ultraviolet-induced changeabilities of wine yeasts from the killer state to sensitive one have been studied. Observed often spontaneous changes of killer and neutral phenotypes under laboratory store conditions as well as high mutation frequency of genetic elements responsible for the killer indication on ultraviolet irradiation testify that often encounterability in nature and in the production of sensitive yeasts is attributed to high frequency of mutation changes of the killer and neutral phenotypes to the sensitive state.

106

Reconstructing Mammalian Phylogenies: A Detailed Comparison of the Cytochrome b and Cytochrome Oxidase Subunit I Mitochondrial Genes  

UK PubMed Central (United Kingdom)

The phylogeny and taxonomy of mammalian species were originally based upon shared or derived morphological characteristics. However, genetic analyses have more recently played an increasingly important...Full Text Available

107

Receptor in group C and G streptococci detects albumin structures present in mammalian species.  

UK PubMed Central (United Kingdom)

The presence of albumin structures with the capacity to bind to a surface receptor in group C and G streptococci was studied in serum samples from 45 mammalian species representing 15 different orders,...Full Text Available

1982-05-01

108

On the function of the mammalian renal papilla and the peristalsis of the surrounding pelvis  

UK PubMed Central (United Kingdom)

This is an informal personal review of the development over time of my ideas about the concentrating mechanism of the mammalian renal papilla. It had been observed that animals with a need to produce...Full Text Available

2011-07-01

109

Mammalian target of rapamycin signaling modulates photic entrainment of the suprachiasmatic circadian clock  

UK PubMed Central (United Kingdom)

Inducible gene expression appears to be an essential event that couples light to entrainment of the master mammalian circadian clock located in the suprachiasmatic nucleus (SCN) of the hypothalamus....Full Text Available

2010-05-05

110

Mammalian end binding proteins control persistent microtubule growth  

UK PubMed Central (United Kingdom)

End binding proteins (EBs) are highly conserved core components of microtubule plus-end tracking protein networks. Here we investigated the roles of the three mammalian EBs in controlling microtubule...Full Text Available

2009-03-09

111

Computational promoter analysis of mouse, rat and human antimicrobial peptide-coding genes  

UK PubMed Central (United Kingdom)

BackgroundMammalian antimicrobial peptides (AMPs) are effectors of the innate immune response. A multitude of signals coming from pathways of mammalian pathogen/pattern recognition...Full Text Available

112

Blarina toxin, a mammalian lethal venom from the short-tailed shrew Blarina brevicauda: Isolation and characterization  

UK PubMed Central (United Kingdom)

Venomous mammals are rare, and their venoms have not been characterized. We have purified and characterized the blarina toxin (BLTX), a lethal mammalian venom with a tissue kallikrein-like activity...Full Text Available

2004-05-18

113

Ethanol production and a case study of ethanol produced from sweet sorghum stalks via solid state fermentation  

Energy Technology Data Exchange (ETDEWEB)

Ethanol has excellent fuel properties, such as high octane, high heat of vaporization and low photochemical reactivity in the atmosphere. It is less volatile than gasoline and there is lower smog formation from evaporative emissions of pure ethanol compared to gasoline. As such, ethanol has emerged as an important alternative energy source that is sustainable, efficient, cost effective, convenient and safe. In 2006, global production of ethanol reached 13.5 billion gallons, up from 12.1 billion gallons in 2005. However, in light of the current debate of food versus fuel, the industry must shift to non-food feedstocks. This paper described an emerging technology to cost-effectively produce ethanol from sweet sorghum stalks, the most promising alternative feedstock to corn, via solid state fermentation (SSF). Experiments of advanced solid state fermentation (ASSF) for ethanol production from sweet sorghum by Saccharomyces cerevisiae were conducted in laboratory and pilot scales studies. ...

2008-07-01

115

Growth hormone-like factor produced by the tapeworm, Spirometra mansonoides, displaces human growth hormone (hGH) from its receptors on cultured human lymphocytes  

International Nuclear Information System (INIS)

An analogue of hGH isolated from plerocercoids of the tapeworm Spirometra mansonoides displaces ["1"2"5I]hGH from its receptors in rabbit, rat, and hamster liver membranes. Biologically, plerocercoid growth factor (PGF) is more similar to hGH than to other mammalian GH's but has not been shown to bond human cells. Receptors specific for hGH have been described on cultured human lymphocytes (IM-9). In this study, the authors compared the binding of PGF and hGH in IM-9 cells and in rabbit hepatic membranes. IM-9 lymphocytes (12 x 10"6 cells/tube) were incubated with ["1"2"5I]hGH and increasing concentrations of hGH (ng/ml) or PGF (serial dilutions) for 90 min at 30"0 C. Specific binding (B_0 - NSB) was determined for each dose of hGH or PGF and the binding curves were analyzed by logit-log regression. The results show that PGF displaced ["1"2"5I]hGH from human cells in a dose ...

1986-04-13

116

The MHC molecules of nonmammalian vertebrates.  

DEFF Research Database (Denmark)

There is very little known about the long-term evolution of the MHC and MHC-like molecules. This is because both the theory (the evolutionary questions and models) and the practice (the animals systems, functional assays and reagents to identify and characterize these molecules) have been difficult to develop. There is no molecular evidence yet to decide whether vertebrate immune systems (and particularly the MHC molecules) are evolutionarily related to invertebrate allorecognition systems, and the functional evidence can be interpreted either way. Even among the vertebrates, there is great heterogeneity in the quality and quantity of the immune response. The functional evidence for T-lymphocyte function in jawless and cartilagenous fish is poor, while the bony fish seem to have many characteristics of a mammalian immune system. The organization and sequence of fish Ig genes also indicate that important events in the evolution of the immune system and the MHC ...

1990-01-01

117

Spark decomposition of SF/sub 6/: Chemical and biological studies  

Energy Technology Data Exchange (ETDEWEB)

Gas-insulated systems employing SF/sub 6/ are utilized in a variety of applications in power delivery systems. Because electric arcs, sparks or corona can decompose SF/sub 6/ into byproducts having chemical properties different from SF/sub 6/, environmental concerns arise regarding inadvertent human exposures to electrically-decomposed SF/sub 6/. Biological assays in our laboratory using mammalian cell culture systems have revealed that spark-decomposed SF/sub 6/ produces cell death, and the extent of cell killing increases with increasing spark energy. Chemical analysis of spark-decomposed SF/sub 6/ has identified the major decomposition pathways and byproducts, but biological testing of individual or byproduct mixtures has indicated that these major decomposition products do not contribute, in a significant fashion, to the cell lethality seen in our assays. Further experiments ...

1987-01-01

118

Cloning and sequencing of cDNA encoding human DNA topoisomerase II and localization of the gene to chromosome region 17q21-22  

Energy Technology Data Exchange (ETDEWEB)

Two overlapping cDNA clones encoding human DNA topoisomerase II were identified by two independent methods. In one, a human cDNA library in phage {lambda} was screened by hybridization with a mixed oligonucleotide probe encoding a stretch of seven amino acids found in yeast and Drosophila DNA topoisomerase II; in the other, a different human cDNA library in a {lambda}gt11 expression vector was screened for the expression of antigenic determinants that are recognized by rabbit antibodies specific to human DNA topoisomerase II. The entire coding sequences of the human DNA topoisomerase II gene were determined from these and several additional clones, identified through the use of the cloned human TOP2 gene sequences as probes. Hybridization between the cloned sequences and mRNA and genomic DNA indicates that the human enzyme is encoded by a single-copy gene. The location of the gene was mapped to chromosome 17q21-22 by in situ hybridization of a cloned fragment to ...

1988-10-01

119

Soil Redox Chemistry Limitation of Selenium Concentration in Carex Species Sedges  

Energy Technology Data Exchange (ETDEWEB)

The trace element selenium (Se) is required in the production of enzymes that protect mammalian cells from oxidative damage due to the byproducts of aerobic respiration. Its deficiency in livestock results in the nutritional muscular dystrophy called white muscle disease. This especially affects juveniles in the preweaning period. Symptoms have also been reported in wild herbivores on low-Se forage, and their appearance may be episodic, suggesting temporal variations in Se uptake by plants. Here, we report variations in selenium concentrations in Carex spp. sedges used as forage by bighorn sheep (Ovis canadensis) on summer range in the Wyoming, Wind River Mountains, and correlate those variations with soil conditions that affect the bioavailability of selenium. Variations in available Se are explained based upon the known oxidation/reduction chemistry of the element. It is concluded that water-saturated, alpine soils provide conditions suitable ...

2007-09-01

120

Proving Stabilization of Biological Systems  

Science.gov (United States)

We describe an efficient procedure for proving stabilization of biological systems modeled as qualitative networks or genetic regulatory networks. For scalability, our procedure uses modular proof techniques, where state-space exploration is applied only locally to small pieces of the system rather than the entire system as a whole. Our procedure exploits the observation that, in practice, the form of modular proofs can be restricted to a very limited set. For completeness, our technique falls back on a non-compositional counterexample search. Using our new procedure, we have solved a number of challenging published examples, including: a 3-D model of the mammalian epidermis; a model of metabolic networks operating in type-2 diabetes; a model of fate determination of vulval precursor cells in the C. elegans worm; and a model of pair-rule regulation during segmentation in the Drosophila embryo. Our results show many orders of magnitude speedup ...

2011-01-01

121

Identification of protein phosphorylation sites within Ser/Thr-rich cluster domains using site-directed mutagenesis and hybrid linear quadrupole ion trap Fourier transform ion cyclotron resonance mass spectrometry  

British Library Electronic Table of Contents (United Kingdom)

We describe a method for the analysis of multi-site phosphorylation in serine/threonine (Ser/Thr)-rich protein sequences. Site-specific mutagenesis was used to introduce tryptic cleavage sites in the serine glutamine/threonine glutamine cluster domain (SCD) of the human checkpoint protein kinase (Chk2). The mutant proteins were shown to autophosphorylate on residues that are inducibly phosphorylated when mammalian cells are exposed to ionizing radiation (serine 33/35, serine 516, threonine 68 and threonine 432). Five Ser/Thr clusters within the SCD were flanked by arginine or lysine residues to produce tryptic peptides for nanospray liquid chromatography (nanoLC)/linear quadrupole ion trap Fourier transform ion cyclotron resonance mass spectrometry. Phosphorylation sites were assigned usin...

2007-01-01

122

Sirtuins, Bioageing, and Cancer  

UK PubMed Central (United Kingdom)

The Sirtuins are a family of orthologues of yeast Sir2 found in a wide range of organisms from bacteria to man. They display a high degree of conservation between species, in both sequence and function,...Full Text Available

123

Iodination of glyceraldehyde 3-phosphate dehydrogenase  

UK PubMed Central (United Kingdom)

1. A high degree of homology in the positions of tyrosine residues in glyceraldehyde 3-phosphate dehydrogenase from lobster and pig muscle, and from yeast, prompted an examination of the reactivity...Full Text Available

1970-09-01

125

Small-molecule screen identifies inhibitors of a human intestinal calcium-activated chloride channel.  

Science.gov (United States)

Calcium-activated chloride channels (CaCCs) are widely expressed in mammalian tissues, including intestinal epithelia, where they facilitate fluid secretion. Potent, selective CaCC inhibitors have not been available. We established a high-throughput screen for identification of inhibitors of a human intestinal CaCC based on inhibition of ATP/carbachol-stimulated iodide influx in HT-29 cells after lentiviral infection with the yellow fluorescent halide-sensing protein YFP-H148Q/I152L. Screening of 50,000 diverse, drug-like compounds yielded six classes of putative CaCC inhibitors, two of which, 3-acyl-2-aminothiophenes and 5-aryl-2-aminothiazoles, inhibited by >95% iodide influx in HT-29 cells in response to multiple calcium-elevating agonists, including thapsigargin, without inhibition of calcium elevation, calcium-calmodulin kinase II activation, or cystic fibrosis transmembrane conductance regulator chloride channels. ...

2007-12-14

126

Cellular Sources of Transforming Growth Factor-? Isoforms in Early and Chronic Radiation Enteropathy  

Science.gov (United States)

The three mammalian transforming growth factor (TGF)-? isoforms (TGF-?1, TGF-?2, and TGF-?3) differ in their putative roles in radiation-induced fibrosis in intestine and other organs. Furthermore, tissue specificity of TGF-? action may result from temporal or spatial changes in production and/or activation. The present study examined shifts in the cell types expressing TGF-? mRNA relative to TGF-? immunoreactivity and histopathological injury during radiation enteropathy development. A 4-cm loop of rat small intestine was locally exposed to 0, 12, or 21-Gy single doses of x-irradiation. Sham-irradiated and irradiated intestine were procured 2 and 26 weeks after irradiation. Cells expressing the TGF-?1, TGF-?2, or TGF-?3 transcripts were identified by in situ hybridization with digoxigenin-labeled riboprobes. Intestinal wall TGF-? immunoreactivity was measured using computerized image analysis, and structural radiation ...

1998-11-01

127

Transformation of Verapamil by Cunninghamella blakesleeana  

UK PubMed Central (United Kingdom)

A filamentous fungus, Cunninghamella blakesleeana AS 3.153, was used as a microbial model of mammalian metabolism to transform verapamil, a calcium channel antagonist. The metabolites...Full Text Available

2004-05-01

128

The hepcidin-binding site on ferroportin is evolutionarily conserved  

UK PubMed Central (United Kingdom)

SummaryMammalian iron homeostasis is regulated by the interaction of the liver-produced peptide hepcidin and its receptor, the iron transporter ferroportin. Hepcidin binds to...Full Text Available

2008-08-01

129

The contribution of lower vertebrate animal models in human reproduction research  

British Library Electronic Table of Contents (United Kingdom)

Many advances have been carried out on the estrogens, GnRH and endocannabinoid system that have impact in the reproductive field. Indeed, estrogens, the generally accepted female hormones, have performed an unsuspected role in male sexual functions thanks to studies on non-mammalian vertebrates. Similarly, these animal models have provided important contributions to the identification of several GnRH ligand and receptor variants and their possible involvement in sexual behavior and gonadal function regulation. Moreover, the use of non-mammalian animal models has contributed to a better comprehension about the endocannabinoid system action in several mammalian reproductive events. We wish to highlight here how non-mammalian vertebrate animal model research contributes to advancements with i...

2011-01-01

130

Specialization and Omnivory in Diverse Mammalian Assemblages  

Science.gov (United States)

... sur un site. Ces espèces présentent un vaste spectre de régimes alimentaires couvrant plusieurs niveaux trophiques et ... ...

131

Phospholipids Trigger Cryptococcus neoformans Capsular Enlargement during Interactions with Amoebae and Macrophages  

UK PubMed Central (United Kingdom)

A remarkable aspect of the interaction of Cryptococcus neoformans with mammalian hosts is a consistent increase in capsule volume. Given...Full Text Available

2011-05-01

132

Gene Networks and the Neuroendocrine Regulation of Puberty  

UK PubMed Central (United Kingdom)

A sustained increase in pulsatile release of gonadotrophin releasing hormone (GnRH) from the hypothalamus is an essential, final event that defines the initiation of mammalian puberty. This...Full Text Available

2010-08-05

133

Francisella Tularensis Metabolism and its Relation to Virulence  

UK PubMed Central (United Kingdom)

Francisella tularensis is a Gram-negative bacterium capable of causing the zoonotic disease tularaemia in a large number of mammalian species and in arthropods. F. tularensis...Full Text Available

135

Analysis of Mammalian Carboxylesterase Inhibition by Trifluoromethylketone-Containing Compounds  

UK PubMed Central (United Kingdom)

Carboxylesterases (CE) are ubiquitous enzymes that hydrolyze numerous ester-containing xenobiotics, including complex molecules, such as the anticancer drugs irinotecan (CPT-11) and capecitabine...Full Text Available

2007-03-01

136

An Application of Supertree Methods to Mammalian Mitogenomic Sequences  

UK PubMed Central (United Kingdom)

Two different approaches can be used in phylogenomics: combined or separate analysis. In the first approach, different datasets are combined in a concatenated supermatrix. In the second, datasets are...Full Text Available

137

The Functionally Conserved Nucleoporins Nup124p from Fission Yeast and the Human Nup153 Mediate Nuclear Import and Activity of the Tf1 Retrotransposon and HIV-1 VprV?  

UK PubMed Central (United Kingdom)

We report that the fission yeast nucleoporin Nup124p is required for the nuclear import of both, retrotransposon Tf1-Gag as well as the retroviral HIV-1 Vpr. Failure to import Tf1-Gag into the nucleus...Full Text Available

2005-04-01

138

Morphological Instabilities in a growing Yeast Colony Experiment and Theory  

CERN Document Server

We study the growth of colonies of the yeast Pichia membranaefaciens on agarose film. The growth conditions are controlled in a setup where nutrients are supplied through an agarose film suspended over a solution of nutrients. As the thickness of the agarose film is varied, the morphology of the front of the colony changes. The growth of the front is modeled by coupling it to a diffusive field of inhibitory metabolites. Qualitative agreement with experiments suggests that such a coupling is responsible for the observed instability of the front.

1997-01-01

139

Dissecting toxin immunity in virus-infected killer yeast uncovers an intrinsic strategy of self-protection  

UK PubMed Central (United Kingdom)

Toxin-secreting “killer” yeasts were initially identified >40 years ago in Saccharomyces cerevisiae strains infected with a double-stranded RNA “killer”...Full Text Available

2006-03-07

140

DNA repair genes  

Energy Technology Data Exchange (ETDEWEB)

Fission yeast S. pombe is assumed to be a good model for cloning of human DNA repair genes, because human gene is normally expressed in S. pombe and has a very similar protein sequence to yeast protein. We have tried to elucidate the DNA repair mechanisms of S. pombe as a model system for those of mammals. (J.P.N.)

1995-12-01

141

Arginine aminoacylation identity is context-dependent and ensured by alternate recognition sets in the anticodon loop of accepting tRNA transcripts.  

UK PubMed Central (United Kingdom)

Yeast arginyl-tRNA synthetase recognizes the non-modified wild-type transcripts derived from both yeast tRNA(Arg) and tRNA(Asp) with equal efficiency. It discriminates its cognate natural substrate,...Full Text Available

1996-09-16

142

Amino acid sequences that determine the nuclear localization of yeast histone 2B.  

UK PubMed Central (United Kingdom)

Histone-beta-galactosidase protein fusions were used to identify the domain of yeast histone 2B, which targets this protein to the nucleus. Amino acids 28 to 33 in H2B were required for nuclear localization...Full Text Available

1987-11-01

143

A heteromeric complex containing the centromere binding factor 1 and two basic leucine zipper factors, Met4 and Met28, mediates the transcription activation of yeast sulfur metabolism.  

UK PubMed Central (United Kingdom)

Transcription activation of sulfur metabolism in yeast is dependent on two DNA binding factors, the centromere binding factor 1 (Cbf1) and Met4. While the role of Met4 was clearly established by showing...Full Text Available

1996-05-15

144

A New Metal-Binding Site for Yeast Phosphoglycerate Kinase as Determined by the Use of a Metal-ATP Analog  

UK PubMed Central (United Kingdom)

Suicide substrate β, γ-bidentate Rh(III)ATP (RhATP) was used to map the metal ion-binding site in yeast phosphoglycerate kinase (PGK). Cleavage of the RhATP-inactivated enzyme with...Full Text Available

1997-02-01

145

The mammalian neuroendocrine hormone norepinephrine supplies iron for bacterial growth in the presence of transferrin or lactoferrin.  

Science.gov (United States)

Norepinephrine stimulates the growth of a range of bacterial species in nutritionally poor SAPI minimal salts medium containing 30% serum. Addition of size-fractionated serum components to SAPI medium indicated that transferrin was required for norepinephrine stimulation of growth of Escherichia coli. Since bacteriostasis by serum is primarily due to the iron-withholding capacity of transferrin, we considered the possibility that norepinephrine can overcome this effect by supplying transferrin-bound iron for growth. Incubation with concentrations of norepinephrine that stimulated bacterial growth in serum-SAPI medium resulted in loss of bound iron from iron-saturated transferrin, as indicated by the appearance of monoferric and apo- isoforms upon electrophoresis in denaturing gels. Norepinephrine also caused the loss of iron from lactoferrin. The pharmacologically inactive metabolite norepinephrine 3-O-sulfate, by contrast, did not result in iron loss from transferrin or lactoferrin ...

2000-11-01

146

Safety evaluation of Propionibacterium freudenreichii ET-3 culture.  

Science.gov (United States)

Propionibacterium freudenreichii ET-3 culture, a cell-free product of whey fermentation using P. freudenreichii ET-3 (7025), has been shown to promote the growth of Bifidobacteria through the action of 1,4-dihydroxy-2-naphthoic acid (DHNA), and therefore, has potential use in the food and supplement industries. Although currently used as a food ingredient in Japan, the safety of this novel ingredient has not been previously evaluated through traditional toxicity testing. Therefore, here we report the results of standard toxicological testing performed on P. freudenreichii ET-3 culture. In a 4-week oral toxicity study, administration of 6000mg/kg body weight/day P. freudenreichii ET-3 culture was without compound-related adverse effects on clinical signs, body weights, food consumption, ophthalmology, hematology, clinical chemistry, urinalysis, organ weights, and gross and microscopic findings in male and female Sprague-Dawley rats. Furthermore, in vitro ...

2011-03-22

147

Organ culture of mammalian skin and the effects of ultraviolet light and testosterone on melanocyte morphology and function  

Science.gov (United States)

Scrotal skin of black Long-Evans rats and human thigh skin were maintained in vitro as organ cultures for as long as 14 days, and examined histologically using the combined skin splitting and Dopa techniques. Selected rat skin cultures received testosterone in the culture medium and/or were irradiated with ultraviolet light (290 to 320 nm uvl). With increased time in culture, scrotal melanocytes round up and there is an increase in epidermal pigmentation. Human skin behaves similarly; after eight days in vitro human melanocytes also become rounded, but remain strongly Dopa-positive. Addition of exogenous testosterone to cultured rat skin maintains dendritic morphology of melanocytes, but cell body size is still reduced. uvl irradiation stimulates melanocytes in rat skin cultures, maintaining their dendritic morphology and increasing epidermal and dermal pigmentation. Cultured skin receiving both uvl and testosterone illustrates a synergistic effect. Electron ...

1978-05-01

148

Immunological detection and quantification of DNA components structurally modified by alkylating carcinogens, mutagens and chemotherapeutic agents  

International Nuclear Information System (INIS)

The detection and quantification of defined reaction products of chemical mutagens and carcinogens (and of many cancer chemotherapeutic agents) with DNA require highly sensitive analytical techniques. The exceptional capability of immunoglobulins to recognize subtle alterations of molecular structure (especially when monoclonal antibodies are used to maximize specificity), outstanding sensitivity of immunoanalysis by high-affinity antibodies, and the fact that radioactively-labelled agents are not required suggest the utility of a radioimmunoassay to recognize and quantitate alkylated DNA products. We have recently developed a set of high-affinity monoclonal antibodies (secreted by mouse x mouse as well as by rat x rat hybridomas; antibody affinity constants, 10"9 to > 10"1"0 lmol) specifically directed against several DNA alkylation products with possible relevance in relation to both mutagenesis and malignant transformation of mammalian ...

1983-09-01

149

Alcohol fermentation in olive oil extraction effluents  

Energy Technology Data Exchange (ETDEWEB)

Eight culture-collection yeast strains of various species and five newly isolated stains were tested for both growth in olive oil extraction effluents and fermentation of the sugars in the same media. The culture-collection yeast strains did not grow in an effluent containing 2.86% sugar (w/v), 8 g/litre phenolic substances, 4.58 g/litre titratable acidity and pH 4.96, whereas the newly isolated strains of Torulopsis sp. MK-1, Saccharomyces norbensis MC-1, S. oleaceus MC-2 and S. oleaginosus grew well and fermented the sugars. In the medium mentioned above, they produced alcohol in amounts of 1.63 to 1.38%, respectively. None of the yeasts grew in an olive oil extraction effluent vacuum-concentrated to over 13-14% of dry matter. The strain of T. sp. MK-1 showed a higher stability.

1989-01-01

150

The effect of pulse voltage and capacitance on biosorption of uranium by biomass derived from whiskey distillery spent wash  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of uranium by residual biomass from The Old Bushmill`s Distillery Co. Ltd., Bushmills, Co. Antrim, Northern Ireland, following exposure to short and intense electric pulses has been examined. The biomass was prepared from the distillery spent wash and consisted of non-viable yeast and bacterial cells. As shown previously, untreated biomass had a maximum biosorption capacity of 170 mg uranium/g dry weight biomass. When biosorption reactions were placed between two electrodes and exposed to electric pulses with field strengths ranging from 1.25-3.25 kV/cm at a capacitance of 25 {mu}F, biosorption increased from 170 mg of uranium to 275 mg uranium/g dry weight biomass. The data were obtained from biosorption isotherm analyses and taken as the degree of biosorption at residual uranium concentrations of 3 mM. In addition, when the capacitance of the electric pulses increased from 0.25 {mu}F to 25 {mu}F at a fixed pulse field strength the ...

1999-01-01

151

The neuronal nicotinic acetylcholine receptor {alpha}7 subunit gene: Cloning, mapping, structure, and targeting in mouse  

Energy Technology Data Exchange (ETDEWEB)

The neuronal nicotinic acetylcholine receptor {alpha}7 subunit is a member of a family of ligand-gated ion channels, and is the only subunit know to bind {alpha}-bungarotoxin in mammalian brain. {alpha}-Bungarotoxin binding sites are known to be more abundant in the hippocampus of mouse strains that are particularly sensitive to nicotine-induced seizures. The {alpha}7 receptor is highly permeable to calcium, which could suggest a role in synaptic plasticity in the nervous system. Auditory gating deficiency, an abnormal response to a second auditory stimulus, is characteristic of schizophrenia. Mouse strains that exhibit a similar gating deficit have reduced hippocampal expression of the {alpha}7 subunit. We have cloned and sequenced the full length cDNA for the mouse {alpha}7 gene (Acra-7) and characterized its gene structure. The murine {alpha}7 shares amino acid identity of 99% and 93% with the rat and human {alpha}7 subunits, respectively. Using an interspecies ...

1994-09-01

152

Effective use of optimized, high-dose (50 kGy) gamma irradiation for pathogen inactivation of human bone allografts.  

Science.gov (United States)

The safety of tissue allografts has come under increased scrutiny due to recent reports of allograft-associated bacterial and viral infections in tissue recipients. We report that 50 kGy of gamma irradiation, nearly three times the dose currently used, is an effective pathogen inactivation method when used under optimized conditions that minimize damage to the tissue. Cancellous bone dowels treated with a radioprotectant solution and 50 kGy of optimized irradiation had an ultimate compressive strength and modulus of elasticity equal to conventionally irradiated (18 kGy) and non-irradiated control bone grafts. We subjected bone dowels treated with this pathogen inactivation method to an in vitro cytotoxicity test using three different mammalian cell lines and concluded that the treated grafts were not cytotoxic. The log reduction of nine pathogens spiked into radioprotectant-treated bone irradiated to 50 kGy was also tested. We achieved 4.9 logs ...

2005-05-01

153

Comparison of internal emitter radiobiology in animals and humans  

Energy Technology Data Exchange (ETDEWEB)

Investigations of radionuclide metabolism and effects in various mammalian species revealed important similarities between animals and humans and between some animal species. These include skeletal deposition of radium and radiostrontium in bone volume; deposition on bone surfaces of plutonium and other actinides; liver deposition of actinides; induction of skeletal or liver malignancies by these radionuclides; induction of tooth and jaw abnormalities; mammary cancer induction by radium in humans and in the beagle; depression of circulating cells in blood; and induction of bone fractures. There are also inter-species differences that may not have been noted if multiple species (including humans) had not been studied. Some of these are more rapid excretion of radium in humans compared with most other mammals; induction by radium of eye melanomas in animals but not humans; rapid loss of deposited plutonium from liver in many species of mice and ...

1997-01-01

154

Characterization of chicken octamer-binding proteins demonstrates that POU domain-containing homeobox transcription factors have been highly conserved during vertebrate evolution  

Energy Technology Data Exchange (ETDEWEB)

The DNA sequence motif ATTTGCAT (octamer) or its inverse complement has been identified as an evolutionarily conserved element in the promoter region of immunoglobulin genes. Two major DNA-binding proteins that bind in a sequence-specific manner to the octamer DNA sequence have been identified in mammalian species--a ubiquitously expressed protein (Oct-1) and a lymphoid-specific protein (Oct-2). During characterization of the promoter region of the chicken immunoglobulin light chain gene, the authors identified two homologous octamer-binding proteins in chicken B cells. when the cloning of the human gene for Oct-2 revealed it to be a member of a distinct family of homeobox genes, they sought to determine if the human Oct-2 cDNA could be used to identify homologous chicken homeobox genes. Using a human Oct-2 homeobox-specific DNA probe, they were able to identify 6-10 homeobox-containing genes in the chicken genome, demonstrating that the ...

1990-02-01

155

Biological Effects after Prenatal Irradiation  

International Nuclear Information System (INIS)

A Task Group of the International Commission on Radiological Protection (ICRP) has finished a report Biological Effects after Prenatal Irradiation (Embryo and Fetus) which has been approved by the Main Commission and Will be Published. Some new important scientific data shall be discussed in this contribution. During the preimplantation period lethality of the mammalian embryo is the dominating radiation effect. However, in mouse strains with genetic predispositions it has been shown that also malformations can be caused. This effect is genetically determined and its mechanisms is different from the induction of malformations during major organogenesis. Radiation exposures during this prenatal period leads ato an increase of genomic instability of cells in the normal appearing fetuses. These radiation effects can be transmitted to the next generation. A renewed analysis of individuals with severe mental retardation after exposures during the ...

156

Variants within the yeast Ty sequence family encode a class of structurally conserved proteins.  

UK PubMed Central (United Kingdom)

The Ty transposable elements of Saccharomyces cerevisiae form a heterogeneous family within which two broad structural classes (I and II) exist. The two classes differ by two large substitutions and...Full Text Available

1985-06-11

157

The recruitment of acetylated and unacetylated tropomyosin to distinct actin polymers permits the discrete regulation of specific myosins in fission yeast  

UK PubMed Central (United Kingdom)

Tropomyosin (Tm) is a conserved dimeric coiled-coil protein, which forms polymers that curl around actin filaments in order to regulate actomyosin function. Acetylation of the Tm N-terminal...Full Text Available

2010-10-01

158

The fission yeast gene pmt1+ encodes a DNA methyltransferase homologue.  

UK PubMed Central (United Kingdom)

DNA methylation of cytosine residues is a widespread phenomenon and has been implicated in a number of biological processes in both prokaryotes and eukaryotes. This methylation occurs at the 5-position...Full Text Available

1995-01-25

159

Structure-Function Study of the N-terminal Domain of Exocyst Subunit Sec3*  

UK PubMed Central (United Kingdom)

The exocyst is an evolutionarily conserved octameric complex involved in polarized exocytosis from yeast to humans. The Sec3 subunit of the exocyst acts as a spatial landmark for exocytosis through...Full Text Available

2010-04-02

160

Some highlights of research on aging with invertebrates, 2010  

UK PubMed Central (United Kingdom)

This annual review focuses on invertebrate model organisms, which continue to yield fundamental new insights into mechanisms of aging. This year, the budding yeast has been used to understand how asymmetrical...Full Text Available

2011-02-01

161

SIRT1 contributes to telomere maintenance and augments global homologous recombination  

UK PubMed Central (United Kingdom)

Yeast Sir2 deacetylase is a component of the silent information regulator (SIR) complex encompassing Sir2/Sir3/Sir4. Sir2 is recruited to telomeres through Rap1, and this complex spreads into subtelomeric...Full Text Available

2010-12-27

162

O2-dependent methionine auxotrophy in Cu,Zn superoxide dismutase-deficient mutants of Saccharomyces cerevisiae.  

UK PubMed Central (United Kingdom)

Mutant strains of the yeast Saccharomyces cerevisiae which lack functional Cu,Zn superoxide dismutase (SOD-1) do not grow aerobically unless supplemented with methionine. The molecular basis of this...Full Text Available

1990-04-01

163

MAPPING THE INITIATOR BINDING TAF2 SUBUNIT IN THE STRUCTURE OF HYDRATED YEAST TFIID  

UK PubMed Central (United Kingdom)

SummaryThe general transcription factor TFIID is a large multi-subunit complex required for the transcription of most protein-encoding genes by RNA polymerase II. Taking advantage...Full Text Available

2009-03-11

164

Legionella fairfieldensis sp. nov. isolated from cooling tower waters in Australia.  

UK PubMed Central (United Kingdom)

Three Legionella-like organisms were isolated from water from the cooling towers of two Australian institutions. The strains grew on buffered charcoal-yeast extract (BCYE) agar but not on BCYE agar...Full Text Available

1991-03-01

165

Increased Ethanol Productivity in Xylose-Utilizing Saccharomyces cerevisiae via a Randomly Mutagenized Xylose Reductase?  

UK PubMed Central (United Kingdom)

Baker's yeast (Saccharomyces cerevisiae) has been genetically engineered to ferment the pentose sugar xylose present in lignocellulose biomass. One of the reactions controlling the...Full Text Available

2010-12-01

166

Improving yield of industrial biomass propagation by increasing the Trx2p dosage  

UK PubMed Central (United Kingdom)

The beneficial effect of improving yeast redox response by increasing thioredoxin levels has been shown. Decreased lipid and protein oxidation is reflected in an increased biomass yield. In addition,...Full Text Available

2010-09-01

167

Identification of Potential Calorie Restriction-Mimicking Yeast Mutants with Increased Mitochondrial Respiratory Chain and Nitric Oxide Levels  

UK PubMed Central (United Kingdom)

Calorie restriction (CR) induces a metabolic shift towards mitochondrial respiration; however, molecular mechanisms underlying CR remain unclear. Recent studies suggest that CR-induced mitochondrial...Full Text Available

168

Identification and Characterization of CPS1 as a Hyaluronic Acid Synthase Contributing to the Pathogenesis of Cryptococcus neoformans Infection?  

UK PubMed Central (United Kingdom)

Cryptococcus neoformans is a pathogenic yeast that often causes devastating meningoencephalitis in immunocompromised individuals. We have previously identified the C. neoformans...Full Text Available

2007-08-01

169

Fuzzy-decision-making problems of fuel ethanol production using a genetically engineered yeast  

Energy Technology Data Exchange (ETDEWEB)

A fuzzy-decision-making procedure is applied to find the optimal feed policy of a fed-batch fermentation process for fuel ethanol production using a genetically engineered Saccharomyces yeast 1400 (pLNH33). The policy consisted of feed flow rate, feed concentration, and fermentation time. The recombinant yeast 1400 (pLNH33) can utilize glucose and xylose simultaneously to produce ethanol. However, the parent yeast utilizes glucose only. A partially selective model is used to describe the kinetic behavior of the process. In this study, this partially selective fermentation process is formulated as a general multiple-objective optimal control problem. By using an assigned membership function for each of the objectives, the general multiple-objective optimization problem can be converted into a maximizing decision problem. In order to obtain a global solution, a hybrid method of differential evolution is introduced to solve ...

1998-08-01

170

Fermentability of Corn Syrups with Different Dextrose Equivalents Added to Various Grape Juices1  

UK PubMed Central (United Kingdom)

It was found that neither the enzymes of the grapes nor those of wine yeast Saccharomyces ellipsoideus strain 223 attacked the higher polysaccharides present in corn syrups. The alcohol...Full Text Available

1967-03-01

171

Expansions, contractions, and fragility of the spinocerebellar ataxia type 10 pentanucleotide repeat in yeast  

UK PubMed Central (United Kingdom)

Spinocerebellar ataxia 10 (SCA10) is an autosomal dominant disease caused by large-scale expansions of the (ATTCT)n repeat within an intron of the human ATXN10 gene. In contrast...Full Text Available

2011-02-15

172

Exit from the Golgi Is Required for the Expansion of the Autophagosomal Phagophore in Yeast Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

The delivery of proteins and organelles to the vacuole by autophagy involves membrane rearrangements that result in the formation of large vesicles called autophagosomes. The mechanism underlying autophagosome...Full Text Available

2010-07-01

173

Engineering ligand-responsive RNA controllers in yeast through the assembly of RNase III tuning modules  

UK PubMed Central (United Kingdom)

The programming of cellular networks to achieve new biological functions depends on the development of genetic tools that link the presence of a molecular signal to gene-regulatory activity. Recently,...Full Text Available

2011-07-01

174

Chemical complementation: A reaction-independent genetic assay for enzyme catalysis  

UK PubMed Central (United Kingdom)

A high-throughput assay for enzyme activity has been developed that is reaction independent. In this assay, a small-molecule yeast three-hybrid system is used to link enzyme catalysis to transcription...Full Text Available

2002-12-24

175

Biotransformation of Explosives by the Old Yellow Enzyme Family of Flavoproteins  

UK PubMed Central (United Kingdom)

Several independent studies of bacterial degradation of nitrate ester explosives have demonstrated the involvement of flavin-dependent oxidoreductases related to the old yellow enzyme (OYE) of yeast....Full Text Available

2004-06-01

176

Arabidopsis thaliana Chromosome 4 Replicates in Two Phases That Correlate with Chromatin State  

UK PubMed Central (United Kingdom)

DNA replication programs have been studied extensively in yeast and animal systems, where they have been shown to correlate with gene expression and certain epigenetic modifications. Despite the conservation...Full Text Available

2010-06-01

177

Altering the ribosomal subunit ratio in yeast maximizes recombinant protein yield  

UK PubMed Central (United Kingdom)

BackgroundThe production of high yields of recombinant proteins is an enduring bottleneck in the post-genomic sciences that has yet to be addressed in a truly rational manner. Typically...Full Text Available

178

Affinity maturation of human botulinum neurotoxin antibodies by light chain shuffling via yeast mating  

UK PubMed Central (United Kingdom)

Botulism is caused by the botulinum neurotoxins (BoNTs), the most poisonous substance known. Because of the high potency of BoNT, development of diagnostic and therapeutic antibodies for botulism requires...Full Text Available

2010-04-01

179

A Novel Form of Transcriptional Silencing by Sum1-1 Requires Hst1 and the Origin Recognition Complex  

UK PubMed Central (United Kingdom)

In the yeast Saccharomyces cerevisiae, a and α mating-type information is stored in transcriptionally silenced cassettes called HML and HMR....Full Text Available

2001-05-01

180

Yeast as a Model System to Study Tau Biology  

Science.gov (United States)

Hyperphosphorylated and aggregated human protein tau constitutes a hallmark of a multitude of neurodegenerative diseases called tauopathies, exemplified by Alzheimer's disease. In spite of an enormous amount of research performed on tau biology, several crucial questions concerning the mechanisms of tau toxicity remain unanswered. In this paper we will highlight some of the processes involved in tau biology and pathology, focusing on tau phosphorylation and the interplay with oxidative stress. In addition, we will introduce the development of a human tau-expressing yeast model, and discuss some crucial results obtained in this model, highlighting its potential in the elucidation of cellular processes leading to tau toxicity.

2011-04-06

182

The effect of substrate modification on microbial growth on surfaces  

Energy Technology Data Exchange (ETDEWEB)

The principle aim of the program was to produce a novel, non-leaching antimicrobial surface for commercial development and future use in the liquid food packaging industry. Antimicrobial surfaces which exist presently have been produced to combat the growth of prokaryotic organisms and usually function as slow release systems. A system which could inhibit eukaryotic growth without contaminating the surrounding 'environment' with the inhibitor was considered of great commercial importance. The remit of this study was concerned with creating a surface which could control the growth of eukaryotic organisms found in fruit juice with particular interest in the yeast, Saccharomyces cerevisiae. Putative antimicrobial surfaces were created by the chemical modification of the test substrate polymers; nylon and ethylvinyl alcohol (EVOH). Surfaces were chemically modified by the covalent coupling of antimicrobial agents known to be active against the ...

1998-07-01

183

The prairie vole: an emerging model organism for understanding the social brain  

UK PubMed Central (United Kingdom)

Unlike most mammalian species, the prairie vole is highly affiliative, forms enduring social bonds between mates, and displays biparental behavior. Over two decades of research in this species...Full Text Available

2010-02-01

184

The comparative structure of mammalian glyceraldehyde 3-phosphate dehydrogenase  

UK PubMed Central (United Kingdom)

1. The amino acid sequences around the thiol groups of glyceraldehyde 3-phosphate dehydrogenase from badger and monkey skeletal muscle were compared with the sequences around the thiol groups in the...Full Text Available

1969-01-01

185

The brown adipocyte differentiation pathway in birds: An evolutionary road not taken  

UK PubMed Central (United Kingdom)

BackgroundThermogenic brown adipose tissue has never been described in birds or other non-mammalian vertebrates. Brown adipocytes in mammals are distinguished from the more common...Full Text Available

186

The Mammalian Neuroendocrine Hormone Norepinephrine Supplies Iron for Bacterial Growth in the Presence of Transferrin or Lactoferrin  

UK PubMed Central (United Kingdom)

Norepinephrine stimulates the growth of a range of bacterial species in nutritionally poor SAPI minimal salts medium containing 30% serum. Addition of size-fractionated serum components to SAPI...Full Text Available

2000-11-01

187

Targeted plasmid integration into the human genome by an engineered zinc-finger recombinase  

UK PubMed Central (United Kingdom)

The development of new methods for gene addition to mammalian genomes is necessary to overcome the limitations of conventional genetic engineering strategies. Although a variety of DNA-modifying enzymes...Full Text Available

2011-09-01

188

Seasonal Protein Changes Support Rapid Energy Production in Hibernator Brainstem  

UK PubMed Central (United Kingdom)

During the torpor phase of mammalian hibernation when core body temperature is near 4°C, the autonomic system continues to maintain respiration, blood pressure and heartbeat despite...Full Text Available

2010-04-01

189

Regulation of Firing Frequency in a Computational Model of a Midbrain Dopaminergic Neuron  

UK PubMed Central (United Kingdom)

Dopaminergic (DA) neurons of the mammalian midbrain exhibit unusually low firing frequencies in vitro. Furthermore, injection of depolarizing current induces depolarization block before high...Full Text Available

2010-06-01

190

Oligodendrocyte-Myelin Glycoprotein and Nogo Negatively Regulate Activity-Dependent Synaptic Plasticity  

UK PubMed Central (United Kingdom)

In the adult mammalian CNS, the growth inhibitors oligodendrocyte-myelin glycoprotein (OMgp) and the reticulon RTN4 (Nogo) are broadly expressed in oligodendrocytes and neurons. Nogo and OMgp...Full Text Available

2010-09-15

191

Of mice and rats: key species variations in the sexual differentiation of brain and behavior  

UK PubMed Central (United Kingdom)

Mice and rats are important mammalian models in biomedical research. In contrast to other biomedical fields, work on sexual differentiation of brain and behavior has traditionally utilized comparative...Full Text Available

2010-07-01

192

Mobilizing diversity: transposable element insertions in genetic variation and disease  

UK PubMed Central (United Kingdom)

Transposable elements (TEs) comprise a large fraction of mammalian genomes. A number of these elements are actively jumping in our genomes today. As a consequence, these insertions provide a source...Full Text Available

193

Minimal distensibility of pulmonary capillaries in avian lungs compared with mammalian lungs  

UK PubMed Central (United Kingdom)

Previous physiological studies suggest that avian pulmonary capillaries behave like almost rigid tubes. We made morphometric measurements to determine the diameter of the capillaries in chicken...Full Text Available

2008-02-01

194

Matching ATP Supply and Demand in Mammalian Heart: In Vivo, In Vitro and In Silico Perspectives  

UK PubMed Central (United Kingdom)

Although the heart rapidly adapts cardiac output to match the body’s circulatory demands, the regulatory mechanisms ensuring that sufficient ATP is available to perform the required...Full Text Available

2010-02-01

195

Massive turnover of functional sequence in human and other mammalian genomes  

UK PubMed Central (United Kingdom)

Despite the availability of dozens of animal genome sequences, two key questions remain unanswered: First, what fraction of any species' genome confers biological function, and second, are apparent...Full Text Available

2010-10-01

196

Mammalian models of extended healthy lifespan  

UK PubMed Central (United Kingdom)

Over the last two centuries, there has been a significant increase in average lifespan expectancy in the developed world. One unambiguous clinical implication of getting older is the risk of experiencing...Full Text Available

2011-01-12

197

Mammalian life-span determinant p66shcA mediates obesity-induced insulin resistance  

UK PubMed Central (United Kingdom)

Obesity and metabolic syndrome result from excess calorie intake and genetic predisposition and are mechanistically linked to type II diabetes and accelerated body aging; abnormal nutrient and insulin...Full Text Available

2010-07-27

198

Mammalian Sirt1: insights on its biological functions  

UK PubMed Central (United Kingdom)

Sirt1 (member of the sirtuin family) is a nicotinamide adenosine dinucleotide (NAD)-dependent deacetylase that removes acetyl groups from various proteins. Sirt1 performs a wide variety of functions...Full Text Available

199

Loss of Nocturnin, a circadian deadenylase, confers resistance to hepatic steatosis and diet-induced obesity  

UK PubMed Central (United Kingdom)

The mammalian circadian system consists of a central oscillator in the suprachiasmatic nucleus of the hypothalamus, which coordinates peripheral clocks in organs throughout the body. Although circadian...Full Text Available

2007-06-05

200

Germline mutagenesis mediated by Sleeping Beauty transposon system in mice  

UK PubMed Central (United Kingdom)

Following the descovery of its transposition activity in mammalian culture systems, the Sleeping Beauty (SB) transposon has since been applied to achieve germline mutagenesis in mice....Full Text Available

2007-01-01

201

Genetics of the mammalian phenylalanine hydroxylase system. Studies of human liver phenylalanine hydroxylase subunit structure and of mutations in phenylketonuria.  

UK PubMed Central (United Kingdom)

Phenylalanine hydroxylase was purified from crude extracts of human livers which show enzyme activity by usine two different methods: (a) affinity chromatography and (b) immunoprecipitation with an...Full Text Available

1979-08-01

202

Frequency of Aneuploidy Related to Age in Porcine Oocytes  

UK PubMed Central (United Kingdom)

It is generally accepted that mammalian oocytes are frequently suffering from chromosome segregation errors during meiosis I, which have severe consequences, including pregnancy loss, developmental...Full Text Available

203

FoxO Transcription Factors in Brain: Regulation and Behavioral Manifestation  

UK PubMed Central (United Kingdom)

BackgroundThe mammalian FoxO transcription factors function to regulate diverse physiological processes. Emerging evidence that both BDNF and lithium suppress FoxO...Full Text Available

2009-01-15

204

Evolution of the redox function in mammalian Apurinic/apyrimidinic endonuclease  

UK PubMed Central (United Kingdom)

Human apurinic/apyrimidinic endonuclease (hApe1) encodes two important functional activities: an essential base excision repair (BER) activity and a redox activity that regulates expression...Full Text Available

2008-08-25

205

Comparative aspects of cortical neurogenesis in vertebrates  

UK PubMed Central (United Kingdom)

The mammalian neocortex consists of six layers. By contrast, the reptilian and avian cortices have only three, which are believed to be equivalent to layers I, V and VI of mammals. In mammals, the majority...Full Text Available

2007-08-01

206

Coevolution of activating and inhibitory receptors within mammalian carcinoembryonic antigen families  

UK PubMed Central (United Kingdom)

BackgroundMost rapidly evolving gene families are involved in immune responses and reproduction, two biological functions which have been assigned to the carcinoembryonic antigen...Full Text Available

207

Chaperonin Containing T-Complex Polypeptide Subunit Eta (CCT-eta) Is a Specific Regulator of Fibroblast Motility and Contractility  

UK PubMed Central (United Kingdom)

Integumentary wounds in mammalian fetuses heal without scar; this scarless wound healing is intrinsic to fetal tissues and is notable for absence of the contraction seen in postnatal (adult) wounds....Full Text Available

208

Changes in Rabbit and Cow Lens Shape and Volume upon Imposition of Anisotonic Conditions  

UK PubMed Central (United Kingdom)

In vivo, mammalian lenses have the capacity to effect fully reversible changes in shape, and possibly volume, during the accommodation process. Isolated lenses also change shape...Full Text Available

2009-10-01

209

Antibody protects against lethal infection with the neurally spreading reovirus type 3 (Dearing).  

UK PubMed Central (United Kingdom)

The mammalian reoviruses have provided a valuable model for studying the pathogenesis of viral infections of the central nervous system (CNS). We have used this model to study the effect of antibody...Full Text Available

1988-12-01

210

Adaptive plasticity of mammalian sperm production in response to social experience  

UK PubMed Central (United Kingdom)

Sperm competition theory predicts that males should invest prudently in ejaculates according to levels of female promiscuity. Males may therefore be sensitive to cues in their social environment associated...Full Text Available

2009-02-22

211

A Comparative Perspective on Minicolumns and Inhibitory GABAergic Interneurons in the Neocortex  

UK PubMed Central (United Kingdom)

Neocortical columns are functional and morphological units whose architecture may have been under selective evolutionary pressure in different mammalian lineages in response to encephalization and specializations...Full Text Available

212

Yeast artificial chromosome libraries containing large inserts from mouse and human DNA  

Energy Technology Data Exchange (ETDEWEB)

Yeast artificial chromosome (YAC) libraries have been difficult to construct with average insert sizes >400 kilobase pairs when DNA is size-fractionated in low-melting-point agarose. By using yeast chromosomes in mock cloning experiments, the authors found that polyamines should be present whenever agarose containing high molecular weight DNA is melted to protect DNA from degradation. By incorporating polyamines during the cloning procedure, they constructed YAC libraries from mouse and human DNA with average insert sizes of 700 and 620 kilobase pairs, respectively. Several genome equivalents of these YAC libraries were replicated onto the surface of many duplicate agar plates using a 40,000 multipin transfer device. High-density filter replicas were screened by hybridization, and 70 mouse YAC clones from 31 loci and 132 human YAC clones from 49 loci were isolated.

1991-05-15

213

Homology analyses of the protein sequences of fatty acid synthases from chicken liver, rat mammary gland, and yeast  

Energy Technology Data Exchange (ETDEWEB)

Homology analyses of the protein sequences of chicken liver and rat mammary gland fatty acid synthases were carried out. The amino acid sequences of the chicken and rat enzymes are 67% identical. If conservative substitutions are allowed, 78% of the amino acids are matched. A region of low homologies exists between the functional domains, in particular around amino acid residues 1059-1264 of the chicken enzyme. Homologies between the active sites of chicken and rat and of chicken and yeast enzymes have been analyzed by an alignment method. A high degree of homology exists between the active sites of the chicken and rat enzymes. However, the chicken and yeast enzymes show a lower degree of homology. The DADPH-binding dinucleotide folds of the {beta}-ketoacyl reductase and the enoyl reductase sites were identified by comparison with a known consensus sequence for the DADP- and FAD-binding dinucleotide folds. The active sites of all of the enzymes ...

1989-11-01

214

Assessment of the role of oxygen and mitochondria in heat shock induction of radiation and thermal resistance in Saccharomyces cerevisiae  

Energy Technology Data Exchange (ETDEWEB)

In response to a heat shock, the yeast Saccharomyces cerevisiae undergoes a large increase in its resistance to heat and, by the induction of its recombinational DNA repair capacity, a corresponding increase in resistance to radiation. Yeast which lack mitochondrial DNA, mitochondria-controlled protein synthetic apparatus, aerobic respiration, and electron transport (rho/sup 0/ strain) were used to assess the role of O/sub 2/, mitochondria, and oxidative processes controlled by mitochondria in the induction of these resistances. We have found that rho/sup 0/ yeast grown and heat shocked in either the presence or absence of O/sub 2/ are capable of developing both radiation and heat resistance. We conclude that neither the stress signal nor its cellular consequences of induced heat and radiation resistance are directly dependent on O/sub 2/, mitochondrial DNA, or mitochondria-controlled protein synthetic or oxidative ...

1983-10-01

215

Removal of uranium from solution using residual brewery yeast: combined biosorption and precipitation  

Energy Technology Data Exchange (ETDEWEB)

Whilst unwashed preparations of biomass from a local brewery had an apparent maximum biosorption capacity for uranium of 360 mg/g (dry weight biomass) washing reduced this maximum to 150 mg/g. Homogenization of both biomass preparations and recovery of cellular debris had no significant effect on the maximum biosorption capacities although at lower equilibrium concentrations of uranium differences in the biosorption capacities were detected. When unwashed biomass was retained by a semi-permeable membrane 40% of uranium used in the experiments precipitated outside that membrane. Therefore a significant proportion of the uranium removed from solution, and previously attributed to biosorption by the yeast biomass, resulted from precipitation brought about by interaction with low molecular weight components loosely associated with the biomass. (Author).

1997-04-01

216

Pectinolytic yeast isolates for cold-active polygalacturonase production  

British Library Electronic Table of Contents (United Kingdom)

Pectin rich cold stored spoiled fruits, vegetables and cold soils were screened and different pectinolytic isolates were obtained by enrichment culturing and ruthenium red plate assay. Among the primary isolates 10-15% were yeast isolates. Six isolates with higher zones of pectin hydrolysis were selected and tested for polygalacturonase (PGU) production at room temperature (25 degrees C) and at 5 degrees C. One isolate identified as Saccharomyces sp. with highest polygalacturonase activity at 5 degrees C was used for enzyme production using raw fruit pectins as substrates. The isolate was identified by preliminary cultural, morphological and sugar fermentation tests. PGU production was high in raw pectin substrates like orange peel (21 U/ml), apple peel (20 U/ml ), mango peel (19 U/ml), ...

2011-01-01

217

Microbiological quality and biophenol content of hot air-dried Thassos cv. table olives upon storage  

British Library Electronic Table of Contents (United Kingdom)

Abstract Microbiological quality and biophenol content evolution was studied in minimally processed Thassos cv table olives by hot air dehydration under mild conditions (40C, 24-h, aw-=-0.893) and storage under characteristic packaging conditions (vacuum, 100% N2 and air) at 4 and 20C over a period of 180 days. No salt was used in the production line or packaging. The undesirable microorganisms (Enterobacteriaceae, Staphylococcus aureus, Bacillus, Clostridium) were undetectable until the end of the storage period. Also, modified atmospheres prevented fungal growth at both temperatures apart from the samples stored in air, in which Penicillium and Aspergillus spp. were identified. At 20C, a coexistence of mesophilic bacteria and yeasts occurred. At 4C, yeasts were the predominant microflora...

2011-01-01

218

Extrinsic allergic alveolitis induced by the yeast Debaryomyces hansenii.  

Science.gov (United States)

A 65-yr-old female developed cough, fever and dyspnoea following repeated exposure to a home ultrasonic humidifier. High-resolution computed tomography showed ground-glass opacity in both lung fields. Arterial blood gas analysis gave an oxygen tension of 8.38 kPa (63 Torr). Pulmonary function testing revealed restrictive ventilatory impairment with a reduction in the diffusing capacity. The diagnosis of extrinsic allergic alveolitis (EAA) was confirmed by radiographic findings, pathological evidence of alveolitis and reproductive development by a provocation test to the humidifier water. The yeast Debaryomyces Hansenii was the only microorganism cultured from the water of the humidifier. The double diffusion precipitating test and lymphocyte proliferative response was positive for an extract of D. Hansenii, providing evidence to incriminate this fungus. This is the first described case of EAA caused by D. Hansenii. PMID:12449192

2002-11-01

219

Effects of dietary glucosylceramide on dermatitis in atopic dermatitis model mice  

British Library Electronic Table of Contents (United Kingdom)

The effects of dietary plant and yeast cerebroside (glucosylceramide), a major sphingolipid in plants and yeast, on atopic dermatitis (AD) like symptoms were investigated in a mouse model. After 7 wk of feeding with a diet containing maize glucosylceramide, plasma IgE levels became significantly lower and in contrast, the levels of interleukin (IL)-12, which induces cellular immunity, became significantly higher in the AD mice than in the controls. However, the sphingolipid constituents of the skin fraction in the maize glucosylceramide fed group did not contain sphingoid bases of plant origin, such as 8-unsaturated sphingoid bases. The results of the present study indicated that dietary plant glucosylceramide prevented AD-like symptoms in AD model mice via regulation of Th1/Th2 balance. P...

2010-01-01

220

Subcellular distribution of ryanodine receptors in the cardiac muscle of carp (Cyprinus carpio).  

Science.gov (United States)

We examined the subcellular localization of ryanodine receptors (RyR) in the cardiac muscle of carp using biochemical, immunohistochemical, and electron microscopic methods and compared it with those of rats and guinea pigs. To achieve this goal, an anti-RyR antibody was newly raised against a synthetic peptide corresponding to an amino acid sequence that was conserved among all sequenced RyRs. Western blot analysis using this antibody detected a single RyR band following the SDS-PAGE of sarcoplasmic reticulum (SR) membranes from carp atrium and ventricle as well as from mammalian hearts and skeletal muscles. The carp heart band had slightly greater mobility than those of mammalian hearts. Although immunohistochemical staining showed evident striations corresponding to the Z lines in longitudinal sections of mammalian hearts, clusters of punctate staining, in contrast, were distributed ubiquitously throughout carp atrium ...

2003-06-12

221

FUEL CELL AND FUEL CELL SYSTEM  

J-STORE (Japan)

Full Text Available

2008-12-12

222

Phylogenetic constraints on digesta separation: Variation in fluid throughput in the digestive tract in mammalian herbivores  

British Library Electronic Table of Contents (United Kingdom)

The relevance of the mean retention time (MRT) of particles through the gastrointestinal tract (GIT) is well understood and MRTparticleGIT is an important parameter in digestion models. Solute markers have been used to estimate MRTsoluteGIT (or 'fluid passage') in animals, but the relevance of this measure is less evident and is usually sought in its relation to MRTparticleGIT. The ratio between the two measures indicates the degree of 'digesta washing', with little washing occurring at ratios of 1, aborad washing at ratios >1 (where the solute marker travels faster than the particle marker), and orad (retrograde) washing at ratios <1 (where the solute marker travels slower than the particle marker). We analysed digesta washing in a dataset of 98 mammalian species including man of differen...

2011-01-01

223

Yeast ribosomal protein L1 is required for the stability of newly synthesized 5S rRNA and the assembly of 60S ribosomal subunits.  

UK PubMed Central (United Kingdom)

Ribosomal protein L1 from Saccharomyces cerevisiae binds 5S rRNA and can be released from intact 60S ribosomal subunits as an L1-5S ribonucleoprotein (RNP) particle. To understand the nature of the...Full Text Available

1993-05-01

224

Wide cross-species aminoacyl-tRNA synthetase replacement in vivo: yeast cytoplasmic alanine enzyme replaced by human polymyositis serum antigen.  

UK PubMed Central (United Kingdom)

Because of variations in tRNA sequences in evolution, tRNA synthetases either do not acylate their cognate tRNAs from other organisms or execute misacylations which can be deleterious in vivo. We report...Full Text Available

1995-05-23

225

The distribution of active RNA polymerase II along the transcribed region is gene-specific and controlled by elongation factors  

UK PubMed Central (United Kingdom)

In order to study the intragenic profiles of active transcription, we determined the relative levels of active RNA polymerase II present at the 3′- and 5′-ends of 261 yeast genes by...Full Text Available

2010-08-01

226

Multiway real-time PCR gene expression profiling in yeast Saccharomyces cerevisiae reveals altered transcriptional response of ADH-genes to glucose stimuli  

UK PubMed Central (United Kingdom)

BackgroundThe large sensitivity, high reproducibility and essentially unlimited dynamic range of real-time PCR to measure gene expression in complex samples provides the opportunity...Full Text Available

227

Molecular methods  

Energy Technology Data Exchange (ETDEWEB)

Chapter 5, describes some of the most important molecular methods used in the study of chromosome structure and function. The methods discussed include fragmentation of DNA, cloning, flow cytometry and chromosome sorting, is situ hybridization, polymerase chain reaction (PCR), and yeast artificial chromosomes (YACs). 18 refs., 3 figs., 1 tab.

1993-12-31

228

Metabolomic analysis of the plant pathogenic fungi Fusarium graminearum and Fusarium culmorum  

Environmental Research Database

DescriptionThis project is part of the BBSRCs special initiative on plant and microbial metabolomics. The project will primarily focus on the trichothecene mycotoxin producing Ascomycete fungus Fusarium graminearum (Fg) which causes ear blight disease of small grain cereals. The project aims to explore the metabolome of various wild-type and single gene deletion Fg strains and to compare some of these with the identical gene mutation in the budding yeast, S. cerevisiae (Sc) and the saprophytic filamentous [continued...

2008-01-31

229

Hybridization with synthetic oligonucleotides  

Science.gov (United States)

Procedures are described for the use of synthetic oligonucleotides for Southern blot experiments and gene bank screening, and the effect of various mismatches on the efficiency of hybridization is demonstrated. The following topics are discussed: sensitivity vs. specificity, hybridization of a 12-mer to the lambda endolysin gene; hybridization of oligonucleotide probes to the E. coli lac operator; hybridization of synthetic probes to the CYC1 gene of yeast; and cloning eucaryotic genes. (HLW)

1978-01-01

230

Genome-wide analysis of N1-methyl-adenosine modification in human tRNAs  

UK PubMed Central (United Kingdom)

The N1-methyl-Adenosine (m1A58) modification at the conserved nucleotide 58 in the TΨC loop is present in most eukaryotic tRNAs. In yeast, m1A58 modification...Full Text Available

2010-07-01

231

Functional and Topological Analysis of Yeast Acyl-CoA:Diacylglycerol Acyltransferase 2, an Endoplasmic Reticulum Enzyme Essential for Triacylglycerol Biosynthesis*  

UK PubMed Central (United Kingdom)

Acyl-CoA:diacylglycerol acyltransferase (EC 2.3.1.20) is a membrane protein present mainly in the endoplasmic reticulum. It catalyzes the final and committed step in the biosynthesis of triacylglycerol,...Full Text Available

2011-04-15

232

Enhanced Degradation of an Endocrine-Disrupting Chemical, Butyl Benzyl Phthalate, by Fusarium oxysporum f. sp. pisi Cutinase  

UK PubMed Central (United Kingdom)

Compared to yeast esterase, fungal cutinase degraded butyl benzyl phthalate (BBP) far more efficiently; i.e., almost 60% of the BBP disappeared within 7.5 h. Also, the final chemical composition significantly...Full Text Available

2002-09-01

233

Biological solubilization of coal in aqueous and nonaqueous media  

Energy Technology Data Exchange (ETDEWEB)

Current investigations into the biological solubilization of coal with microorganisms focus on the production of solubilizing activity in fungi. Test organisms for this work include a species of the yeast Candida previously isolated from a lignite outcrop, and P. chrysosporium, a filamentous higher fungus which has played a major role in lignin biodegradation research. The studies described are primarily exploratory in nature, and are fundamental to the design of more sophisticated inquiries into the physiology of fungal coal solubilization.

1987-01-01

234

Assembly of 60S ribosomal subunits is perturbed in temperature-sensitive yeast mutants defective in ribosomal protein L16.  

UK PubMed Central (United Kingdom)

Temperature-sensitive mutants defective in 60S ribosomal subunit protein L16 of Saccharomyces cerevisiae were isolated through hydroxylamine mutagenesis of the RPL16B gene and plasmid shuffling. Two...Full Text Available

1991-11-01

235

cDNA Cloning of the Basement Membrane Chondroitin Sulfate Proteoglycan Core Protein, Bamacan: A Five Domain Structure Including Coiled-Coil Motifs  

UK PubMed Central (United Kingdom)

Basement membranes contain several proteoglycans, and those bearing heparan sulfate glycosaminoglycans such as perlecan and agrin usually predominate. Most mammalian basement membranes also contain...Full Text Available

1997-01-27

236

Molecular Characterization of a Haemaphysalis longicornis Tick Salivary Gland-Associated 29-Kilodalton Protein and Its Effect as a Vaccine against Tick Infestation in Rabbits  

UK PubMed Central (United Kingdom)

The use of tick vaccines in mammalian hosts has been shown to be the most promising alternative tick control method to current use of acaricides, which suffers from a number of limitations. However,...Full Text Available

1999-04-01

237

Comparative analysis of the ATRX promoter and 5' regulatory region reveals conserved regulatory elements which are linked to roles in neurodevelopment, alpha-globin regulation and testicular function  

UK PubMed Central (United Kingdom)

BackgroundATRX is a tightly-regulated multifunctional protein with crucial roles in mammalian development. Mutations in the ATRX gene cause ATR-X syndrome, an X-linked...Full Text Available

238

Cellular Sources of Transforming Growth Factor-? Isoforms in Early and Chronic Radiation Enteropathy  

UK PubMed Central (United Kingdom)

The three mammalian transforming growth factor (TGF)-β isoforms (TGF-β1, TGF-β2, and TGF-β3) differ in their putative roles in radiation-induced fibrosis in intestine...Full Text Available

1998-11-01

239

Binding the Mammalian High Mobility Group Protein AT-hook 2 to AT-Rich Deoxyoligonucleotides: Enthalpy-Entropy Compensation  

UK PubMed Central (United Kingdom)

HMGA2 is a DNA minor-groove binding protein. We previously demonstrated that HMGA2 binds to AT-rich DNA with very high binding affinity where the binding of HMGA2 to poly(dA-dT)2 is enthalpy-driven...Full Text Available

2009-05-20

240

Thin Film Solar Cells and Solar Cell Testing, Volume II Proceedings of the Fourth Photovoltaic Specialists Conference  

Science.gov (United States)

Thin film solar cells and solar cell testing - photovoltaic cells, radiation damage to cadmium sulfide solar cells, and airplane testing of solar cells

1964-01-01

241

Stem cells: Research tools and clinical treatments  

British Library Electronic Table of Contents (United Kingdom)

Abstract The term -stem cell- most commonly refers to embryonic stem cells, particularly in the lay media; however, it also describes other cell types. A stem cell represents a cell of multi-lineage potential with the ability for self-renewal. It is now clear that the plasticity and immortality of a given stem cell will depend on what type of stem cell it is, whether an embryonic stem cell, a fetal-placental stem cell or an adult stem cell. Stem cells offer great promise as cell-based therapies for the future. With evolving technology, much of the socio-political debate regarding stem cells can now be avoided.

2011-01-01

242

Long-Lasting Inhibitory Effects of Fetal Liver Mesenchymal Stem Cells on T-Lymphocyte Proliferation  

UK PubMed Central (United Kingdom)

Human bone marrow mesenchymal stem cells (BM-MSC) are multipotent progenitor cells that have transient immunomodulatory properties on Natural Killer (NK) cells, Dendritic Cells (DC), and T cells. This...Full Text Available

243

Management of industrial solid wastes in Alexandria, Egypt  

Science.gov (United States)

This paper presents a summary of the first phase of the EPA project, which encompasses surveys of residues from industrial sources in Alexandria. Studies to date indicate that wastes from various industries can be recovered economically. Wastes such as tin cans, glass, wastepaper, and food residues from processing of fruits, starch, and beer are examples of reusable industrial wastes in Egypt. The results of experimental studies for reuse of residues from oil refining, starch and yeast processing, and steel pickling are presented. Spent clay from edible oil refining is currently discarded, causing both handling and disposal problems. This clay contains as much as 40% oil; 90% can be recovered by extraction. The recovered oil can be successfully used in soap production, and the spent clay can be reused in oil bleaching. Other examples include starch and yeast wastes, which can be used for animal feed, and spent pickling liquor, which can be used ...

1983-03-01

244

Mineral biotechnology. Microbial aspects of mineral beneficiation, metal extraction, and environmental control  

Energy Technology Data Exchange (ETDEWEB)

Papers in this book illustrate the utility of mineral biotechnology with respect to biobeneficiation, bioleaching, bioremediation and biomineralization. Papers of particular interest to the coal industry include: depression of pyrite flotation by yeast and bacteris (S.K. Kawatra and T.C. Eisele); desulfurization of coal by microbial flotation in a semicontinuous system (T. Nagaoka and others); biochemical removal of HAP precursors from coal - INEEL slurry column testing (K.S. Noah and G.J. Olson); microorganisms, biotechnology and acid rock drainage - emphasis on passive-biological control and treatment methods (N. Kuyucak); and utility of bioreagents in mineral processing (P. Somasundaran and others).

2001-07-01

245

Latvian scientists research into chemical uses of timber  

Energy Technology Data Exchange (ETDEWEB)

Scientists of the Institute of Wood Chemistry of the Latvian Academy of Sciences have developed two highly efficient processes for producing furfural, a feedstock for varnishes, synthetic resins and plastics. It is made of production wastes, including branches and small-dimension timber. By one process, the raw material is chipped, treated first with diluted sulphuric acid and then with steam heated to 250 degrees C. The other uses concentrated sulphuric acid as a catalyst. Besides furfural, this process also yields sugar solutions used in alcohol and nutrient yeast production.

1982-03-20

246

Antifungal activity of Glycyrrhiza glabra extracts and its active constituent glabridin  

British Library Electronic Table of Contents (United Kingdom)

Glabridin, an active constituent of Glycyrrhiza glabra roots, was found to be active against both yeast and filamentous fungi. Glabridin also showed resistance modifying activity against drug resistant mutants of Candida albicans at a minimum inhibitory concentration of 31.25-250 g/mL. Although the compound was reported earlier to be active against Candida albicans, but this is the first report of its activity against drug resistant mutants. Copyright Copyright 2009 John Wiley & Sons, Ltd.

2009-01-01

248

Simultaneous recognition and segmentation of cells: application in C.elegans  

UK PubMed Central (United Kingdom)

Motivation: Automatic recognition of cell identities is critical for quantitative measurement, targeting and manipulation of cells of model animals at single-cell resolution. It has been...Full Text Available

2011-10-15

250

Antifungal activity of the extracts and neolignans from Piper regnellii (Miq.) C. DC. var. pallescens (C. DC.) Yunck  

Energy Technology Data Exchange (ETDEWEB)

Piper regnellii (Miq.) C. DC. var. pallescens (C. DC.) Yunck (Piperaceae) is a medicinal plant traditionally used in Brazil to treat infectious diseases. The extracts obtained from the leaves of P. regnellii were investigated for their antifungal activities against the yeasts Candida albicans, C. krusei, C. parapsilosis, and C. tropicalis. The EtOAc extract presented gnificant activity against Candida albicans with MIC at 125 {mu}g mL{sup -1}, and a moderate activity against both C. krusei and C. parapsilosis with MIC at 500 {mu}g mL{sup -1}. Candida tropicalis was not inhibited by this extract at concentrations as high as 1000 {mu}g mL{sup -1}. Based on these findings, the EtOAc extract was fractionated by silica gel column chromatography into nine fractions. The hexane and CHCl{sub 3} fractions showed varied levels of antifungal activity against all test yeasts. Further column chromatography separation of the hexane fraction afforded the pure ...

2005-11-15

251

Visualization of growth factor receptor sites in rat forebrain  

International Nuclear Information System (INIS)

It is now known that various growth factors may also act in the central nervous system. Among them, it has recently been shown that epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) may possess trophic effects in the mammalian brain. We report here on the respective autoradiographic distribution of ["1"2"5I]EGF and ["1"2"5I]IGF-I receptor binding sites in the rat brain, both during ontogeny and in adulthood. It appears that ["1"2"5I]EGF sites are mostly found in the rat forebrain during brain development. On the other hand, ["1"2"5I]IGF-I sites are more widely distributed both during ontogeny and in adulthood. These results reveal the plasticity of the expression of EGF and IGF-I receptor sites in the mammalian brain. This could be relevant for the respective role of these two growth factors in the development and maintenance of neuronal function.

252

Kinetics of complexing activation by the magnesium ion on green crab (Scylla serrata) alkaline phosphatase.  

Science.gov (United States)

As with mammalian enzymes, green crab (Scylla serrata) alkaline phosphatase can be activated by Mg2+ through a time-dependent course. The activation is mainly a Vmax effect. Tsou's method was used to study the kinetic course of activation. The results show that the enzyme was activated by a complexing scheme that had not been previously identified: the enzyme first reversibly and quickly binds Mg2+ and then undergoes a slow reversible course to activation, with a relatively high activation energy (78 +/- 4 kJ/mol) and a slow conformational change. The activation reaction is a single molecule reaction, and the apparent activation rate constant is independent of Mg2+ concentration if the concentration is sufficiently high. The microscopic rate constants of activation and the association constant were determined from the measurements. The proposed scheme may also be applied to the Mg2+ activation mechanism for mammalian enzyme, to explain why the ...

2001-01-01

253

FMRFamide-like immunoreactivity in rat brain: development of a radioimmunoassay and its application in studies of distribution and chromatographic properties  

International Nuclear Information System (INIS)

A radioimmunoassay is described for the molluscan neuropeptide, Phe-Met-Arg-Phe-NH"2(FMRFamide). The antibody used is C-terminal-specific and shows slight but significant (1-2%) cross-reactivity with chicken pancreatic polypeptide (APP). The assay has been used to identify in rat brain extracts a pair of molecules that may represent mammalian counterparts of FMRFamide. Their concentrations were highest in spinal cord and hypothalamus (>10 pmol.g"-_1) and lowest in cerebellum and striatum (<3.5 pmol.g"-_1). The two immunoreactive peptides were separated on CM ion-exchange chromatography where they appeared to be less basic than FMRFamide. On Sephadex G50 gel filtration one eluted in a similar position to FMRFamide and the other slightly earlier suggesting it may be of higher molecular weight. The rat immunoreactive components do not correspond to previously described neuropeptides or hormones, and may be members of a new group of mammalian ...

254

Trends in Neuroendocrinology  

British Library Electronic Table of Contents (United Kingdom)

The mammalian circadian timing system is organized into hierarchical structures with a central clock in the suprachiasmatic nucleus (SCN) and subsidiary peripheral oscillators. After the discovery of the local clockwork in peripheral organs and tissues, which have a molecular makeup similar to the central pacemaker SCN, uncovering the roles of the peripheral clock in the rhythmic physiology has been an emerging goal in chronobiology. Glucocorticoid (GC) is a multifunctional adrenal steroid hormone that shows a robust circadian rhythm. The daily GC rhythm has long been thought to be governed by the SCN via the hypothalamus-pituitary-adrenal neuroendocrine axis. Recent findings, however, indicate that multiple regulatory mechanisms, including the adrenal intrinsic mechanism by the peripheral...

2011-01-01

255

Interpreting Mammalian Evolution using Fugu Genome Comparisons  

Energy Technology Data Exchange (ETDEWEB)

Comparative sequence analysis of the human and the pufferfish Fugu rubripes (fugu) genomes has revealed several novel functional coding and noncoding regions in the human genome. In particular, the fugu genome has been extremely valuable for identifying transcriptional regulatory elements in human loci harboring unusually high levels of evolutionary conservation to rodent genomes. In such regions, the large evolutionary distance between human and fishes provides an additional filter through which functional noncoding elements can be detected with high efficiency.

2004-04-02

256

Health effects[1997 Scientific Report of the Belgian Nuclear Research Centre  

Energy Technology Data Exchange (ETDEWEB)

The objectives of the research in the field of epidemiology , performed at the Belgian Nuclear Research Centre SCK-CEN are (1) to study cancer mortality and morbidity in nuclear workers in Belgium; (2) to document the feasibility of retrospective cohort studies in Belgium; (3) to participate in the IARC study. For radiobiology, the main objectives are: (1) to elucidate the mechanisms of the effects of ionizing radiation on the mammalian embryo during the early phase of its development, (2) to assess the genetic risks of maternal exposure to ionizing radiation, (3) to elucidate the mechanisms by which damage to the brain and mental retardation are caused in man after prenatal irradiation. The main achievements in these domains for 1997 are presented.

1998-07-01

257

Acceleration of Emergence of Bacterial Antibiotic Resistance in Connected Microenvironments.  

Science.gov (United States)

The emergence of bacterial antibiotic resistance is a growing problem, yet the variables that influence the rate of emergence of resistance are not well understood. In a microfluidic device designed to mimic naturally occurring bacterial niches, resistance of Escherichia coli to the antibiotic ciprofloxacin developed within 10 hours. Resistance emerged with as few as 100 bacteria in the initial inoculation. Whole-genome sequencing of the resistant organisms revealed that four functional single-nucleotide polymorphisms attained fixation. Knowledge about the rapid emergence of antibiotic resistance in the heterogeneous conditions within the mammalian body may be helpful in understanding the emergence of drug resistance during cancer chemotherapy. PMID:21940899

2011-09-23

261

First-generation fuel cell demonstration and commercialization activities  

International Nuclear Information System (INIS)

... electric utilities electrochemistry energy storage fuel cells organizational models

262

Applied and fundamental aspects of plant cell, tissue, and organ culture  

CERN Document Server

Applied and fundamental aspects of plant cell, tissue, and organ culture

1977-01-01

263

Telomeric DNA in normal and leukemic blood cells.  

UK PubMed Central (United Kingdom)

We studied telomeric DNA in leukemic cells as well as in normal T cells, B cells, monocytes, polymorphonuclear leukocytes, and bone marrow hematopoietic progenitor cells. No marked differences were...Full Text Available

1995-03-01

264

Putative intermediates in the nerve cell differentiation pathway in hydra have properties of multipotent stem cells  

Energy Technology Data Exchange (ETDEWEB)

We have investigated the properties of nerve cell precursors in hydra by analyzing the differentiation and proliferation capacity of interstitial cells in the peduncle of Hydra oligactis, which is a region of active nerve cell differentiation. Our results indicate that about 50% of the interstitial cells in the peduncle can grow rapidly and also give rise to nematocyte precursors when transplanted into a gastric environment. If these cells were committed nerve cell precursors, one would not expect them to differentiate into nematocytes nor to proliferate apparently without limit. Therefore we conclude that cycling interstitial cells in peduncles are not intermediates in the nerve cell differentiation pathway but are stem cells. The remaining interstitial cells in the peduncle are ...

1990-12-01

265

Solar Cell Radiation Response near the Interface of Different ...  

Science.gov (United States)

... Solar Cell Radiation Respinnse Near the Interface o~f fliffprerv- ... 5 4. CALCUTl-ATED SOLAR CELL RLSPONSE FOR VARIOUS BASE MATERIALS ...

1971-11-01

266

Silicon solar cell assembly  

Science.gov (United States)

A silicon solar cell assembly comprising a large, thin silicon solar cell bonded to a metal mount for use when there exists a mismatch in the thermal expansivities of the device and the mount.

1979-01-01

267

Patterns of proliferation and differentiation of irradiated haemopoietic stem cells cultured on normal 'stromal' cell colonies in vitro  

Energy Technology Data Exchange (ETDEWEB)

Experiments were designed to elucidate whether or not the irradiated bone marrow cells receive any stimulation for the self-replication and differentiation from normal 'stromal' cell colonies in the bone marrow cell culture in vitro. When irradiated or unirradiated bone marrow cells were overlaid on the normal adherent cell colonies, the proliferation of haemopoietic stem cells was supported, the degree of the stimulation depending on the starting cellular concentration. There was, however, no significant changes in the concentration of either CFUs or CFUc regardless of the dose of irradiation on the bone marrow cells overlaid. This was a great contrast to the dose-dependent decrease of CFUs or CFUc within the culture in which both the stem cells and stromal cells were ...

1981-09-01

268

Oxidation of ethane by an Acremonium species.  

UK PubMed Central (United Kingdom)

Ethane oxidation was studied in ethane-grown resting cells (mycelia) of an Acremonium sp. and in cell-free preparations of such mycelia. From resting cell experiments evidence was found for a pathway...Full Text Available

1976-07-01

269

Of Microenvironments and Mammary Stem Cells  

UK PubMed Central (United Kingdom)

In most adult tissues there reside pools of stem and progenitor cells inside specialized microenvironments referred to as niches. The niche protects the stem cells from inappropriate expansion...Full Text Available

2007-06-01

270

Laser-Based Fuel Cell Manufacturing for Thermal ...  

Science.gov (United States)

... FLUENT PEM fuel cell toolbox is actually composed of many User Defined Functions that are incorporated into the fuel cell model developed by ...

2005-10-12

271

Fuel Cell Technologies Equipment on Environmental Expert  

Wastenet

... Fuel Cell Technologies Equipment on Environmental Expert Find and compare a variety of fuel cell technologies equipment on the world's largest environmental industry portal. View ...

273

Embryonic Retinal Cells and Support to Mature Retinal Neurons  

UK PubMed Central (United Kingdom)

Purpose.There is a paucity of neuron replacement studies for retinal ganglion cells. Given the complex phenotype of these neurons, replacement of ganglion cells may be impossible....Full Text Available

2010-04-01

274

Culture of cells from beagles with bronchioloalveolar carcinoma  

International Nuclear Information System (INIS)

Cell cultures were prepared from lung tumors occurring in beagles following exposure to inhaled plutonium. Morphologic and growth characteristics of two of these cell lines are described.

1977-05-01

276

Wiley::The Wiley Encyclopedia of Packaging Technology, 3rd Edition  

Wastenet

...The+Wiley+Encyclopedia+of+Packaging+Technology%2C+3rd+Edition FO21+Food+Packaging Wiley::The Wiley Encyclopedia of Packaging Technology, 3rd Edition WILEY ...US | HELP Home / Chemistry / Food Science & Technology / Food Processing, Production & Manufacture / Food Packaging / The Wiley Encyclopedia of Packaging Technology, 3rd Edition ...Manufacture Sensory Science Food Biotechnology Food Chemistry Food Engineering Related Titles Food Packaging Brewing Yeast and Fermentation by Chris Boulton, David Quain Food ...Editor) Journal of Food Process Engineering Journal of Food Processing and Preservation Packaging Research in Food Product Design and Development by Howard R. ...

277

The antimicrobial efficacy of a silver alginate dressing against a broad spectrum of clinically relevant wound isolates  

British Library Electronic Table of Contents (United Kingdom)

Wound dressings impregnated with silver have a role to play in aiding to reduce both the dressing and wound microbial bioburden. It is therefore imperative that antimicrobial wound dressings have efficacy on a broad range of clinical significant microorganisms. Accordingly, this study aimed to determine the antimicrobial efficacy of a silver alginate dressing against 115 wound isolates that had been isolated routinely from patients at West Virginia University Hospital. Standardised corrected zones of inhibition (CZOIs) were performed on all clinical isolates. It was found that the silver alginate dressing was able to inhibit the growth of all microorganisms tested. In particular, the silver alginate dressing inhibited the growth of Candida albicans and yeasts with CZOI of 3-115 mm. All met...

2011-01-01

278

Synthesis and study of the antifungal activity of new mono- and disubstituted derivatives of a genetically engineered polyene antibiotic 28,29-didehydronystatin A1 (S44HP)  

British Library Electronic Table of Contents (United Kingdom)

Mono- and disubstituted novel derivatives of the heptaene nystatin analog 28,29-didehydronystatin A1 (S44HP, 1) were obtained by chemical modification of the exocyclic C-16 carboxyl and/or an amino group of mycosamine moiety. The strategy of preparation of mono- and double-modified polyene macrolides was based on the use of intermediate hydrophobic N-Fmoc (9-fluorenylmethoxycarbonyl) derivatives that facilitated the procedures of isolation and purification of new compounds. The antifungal activity of the new derivatives was first tested in vitro against yeasts and filamentous fungi, allowing the selection of the most active compounds that were subsequently tested for acute toxicity in mice. 2-(N,N-dimethylamino)ethylamide of 1 (2) and 2-(N,N-dimethylamino)ethylamide of N-fructopyranosyl-28...

2010-01-01

279

In vitro effects of medium tonicity, nutrient concentration, and free chlorine content on Acanthamoeba  

British Library Electronic Table of Contents (United Kingdom)

Background: The environment preferred by Acanthamoeba trophozoites and the mechanism by which the amebae enters the cornea are not yet fully understood. A better understanding of the pathogenesis of this disease may help with prevention and treatment. Purpose: To define the preferred environments for Acanthamoeba survival and proliferation in vitro by examining the effect of tonicity, nutrient concentration, and free chlorine content on Acanthamoeba. Materials and methods: Human corneal isolates of Acanthamoeba castellanii and Acanthamoeba polyphaga trophozoites were cultured at 22^oC (room temperature) in PYG (peptone-yeast extract-glucose) medium. The effect of tonicity on amebae was determined by incubating trophozoites in sodium chloride solutions in concentrations ranging from 0% to 1...

2011-01-01

280

Enhancement of bioleaching of a spent Ni/Mo hydroprocessing catalyst by Penicillium simplicissimum  

British Library Electronic Table of Contents (United Kingdom)

Statistically based experimental designs were applied to screen and optimize the bioleaching of spent hydrocracking catalyst by Penicillium simplicissimum. Eleven factors were examined for their significance on bioleaching using a Plackett-Burman factorial design. Four significant variables (pulp density, sucrose, NaNO"3, and yeast extract concentrations) were selected for the optimization studies. The combined effect of these variables on metal bioleaching was studied using a central composite design (CCD). Second-order polynomials were established to identify the relationship between the recovery percent of the metals and the four significant variables. The optimal values of the variables for maximum metals bioleaching were as follows: pulp density (4.0%, w/v), sucrose (90g/L), NaNO"3 (2...

2011-01-01

281

Curcumin Binding to DNA and RNA  

British Library Electronic Table of Contents (United Kingdom)

Curcumin, the yellow pigment from the rhizoma of Curcuma longa, is a widely studied phytochemical with a variety of biological activities. The ongoing research and clinical trials have proved that this natural phenolic compound has great and diverse pharmacological potencies. Beside its effective antioxidant, antiinflammatory, and antimicrobial/antiviral properties, curcumin is also considered as a cancer chemopreventive agent. While the antioxidant activity of curcumin is well documented, its interaction with DNA and RNA is not fully investigated. This study was designed to examine the interactions of curcumin with calf thymus DNA and yeast RNA in aqueous solution at physiological conditions, using constant DNA and RNA concentration (6.25?mM) and various curcumin/polynucleotide (phosphate...

2009-01-01

282

Comparison of media and methods for detecting and enumerating Listeria monocytogenes in refrigerated cabbage.  

Science.gov (United States)

Direct plating, selective enrichment, and cold enrichment followed by secondary selective enrichment procedures were compared for detecting and enumerating Listeria monocytogenes in chopped cabbage stored at 5 degrees C for up to 64 days. Addition of Fe3+ to solid media enhanced detection of the organism. Cold enrichment (5 degrees C) in nutrient broth and brain heart infusion broth followed by secondary enrichment (48 h, 30 degrees C) in Trypticase soy-yeast extract-antibiotic broth and thiocyanate-nalidixic acid broth and plating on selective agar media (Doyle and Schoeni selective enrichment agar [minus acriflavin hydrochloride, supplemented with 5 micrograms of Fe3+/ml] and McBride Listeria agar) resulted in the detection of highest populations. PMID:3111369

1987-05-01

283

Biological treatment of wine of distilleries  

International Nuclear Information System (INIS)

The potential of the yeast Candida tropicalis and Candida guillermondii was evaluated and an isolated partnership of microorganisms of waters of the Medellin River, conformed by two bacteria and one leavening, to degrade the content of organic matter present in wine produced by the factory of Licores and Alcoholes de Antioquia (FLA) in aerobic process with biomass production. For each one of the microorganisms in study this capacity of removal in units of chemical demand of oxygen was quantified (CDO); in addition, parameters were analyzed such as yield of the biomass in relation to the removed CDO and to total reducing sugars (TRS) consumed, time of fermentation and speed of growth different dilutions from wine. Also the possible inhibition was analyzed that the present phenolic compounds in this wine can cause in the biological process of degradation.

284

Bioconvertion of spent cellulose sausage casings  

British Library Electronic Table of Contents (United Kingdom)

Cellulose sausage cellulose casings are used extensively in the manufacture of sausages in meat packaging. After stripping the meat, spent casings mainly contain cellulose and residual meat juice with salt, nitrate and nitrite. Disposal of spent sausage casings has serious economic and environmental concerns for the sausage industry. This work describes bioconversion of spent cellulose casings (SCC) into enzymes, lactic acid and ethanol by using cellulolytic fungi, lactobacillus and yeasts. The solid substrate cultivation (SSC) of Trichoderma reesei RUT C-30 on SCC and blends gave a maximum of 152 filter paper cellulase (FPase) activity and about 100 carboxymethylcellulase activity (CMCase)/g dry weight substrate. The SSC produced enzyme-rich casing with 50 FPase when directly mixed as suc...

2008-01-01

285

Antimicrobial silver-montmorillonite nanoparticles to prolong the shelf life of fresh fruit salad  

British Library Electronic Table of Contents (United Kingdom)

In this work, silver-montmorillonite (Ag-MMT) antimicrobial nanoparticles have been obtained by allowing silver ions from nitrate solutions to replace the Na^+ of natural montmorillonite and then to be reduced by a thermal treatment. Ag-MMT were used as active antimicrobial compounds to improve the shelf life of fresh fruit salad. In order to assess their influence on product shelf life, sensorial and microbiological quality has been monitored during the storage. The microbiological quality was determined by monitoring the principal spoilage microorganisms (mesophilic and psychrotrophic bacteria, coliforms, lactic acid bacteria, yeasts and molds). Additionally, the evolution of sensorial quality was assessed by monitoring color, odor, firmness and product overall quality. The Ag-MMT nanopa...

2011-01-01

286

Aerobic Decolorization and Detoxification of a Disperse Dye in Textile Effluent by a New Isolate of Bacillus sp.  

British Library Electronic Table of Contents (United Kingdom)

A number of aerobic species capable of decolorizing some of the dyes in a textile mill effluent were isolated. One of the isolates was able to decolorize Terasil black dye under aerobic conditions in the presence of an exogenous carbon source after 5 days. Glucose or starch (%1 ea) are essential for decolorization but the process proceeds faster in the presence of 0.5% yeast extract. Results of the BOD5 show that the untreated effluent samples have a low BOD value, whereas treated samples show an initial increase in BOD up to 15 days followed by a decrease after 20 days. FT-IR and GC-MS data also reveal that the initial components in the untreated effluent disappear after 20 days of treatment, confirming biodegradation of the dye. Phytotoxicity tests on the untreated effluent samples using...

2006-01-01

287

A lytic enzyme cocktail from Streptomyces sp. B578 for the control of lactic and acetic acid bacteria in wine  

British Library Electronic Table of Contents (United Kingdom)

Beside yeasts, lactic acid bacteria (LAB) are the most abundant microbes in must during vinification. Whereas Oenococcos oeni is commercially used as a starter culture for the biological acid reduction in wines, other species are responsible for different types of wine spoilage. Members of the genera Pediococcus, Weissella, Leuconostoc, and Lactobacillus are producers of exopolysaccharide slimes, biogenic amines, acetic acid, and other off-flavors. In order to control microbial growth, different procedures such as heating of must and addition of sulfite or lysozyme from egg white are generally applied. Yet, because of health risks, the application of sulfite should be reduced and lysozyme is not effective against all LAB. In this study, we describe exoenzymes from a Streptomyces sp. strain...

2009-01-01

288

Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells in irradiated bone marrow cell culture in vitro  

Energy Technology Data Exchange (ETDEWEB)

Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells after irradiation were studied in the long-term culture of mouse bone marrow cells in vitro. No difference was observed in the survival of the stem cells among cultures in which 0 - 10/sup 7/ cells were re-inoculated on the adherent cell colonies in the culture flask. Stem cells showed a significant proliferation within 1 week and the number of the stem cells exceeded the control in 3 weeks after irradiation in the cultures with less than 10/sup 6/ re-inoculated cells per flask. In contrast, there was a considerable delay in the onset of stem cell proliferation after irradiation in the culture with 10/sup 7/ cells per flask. Based on these results, a possibility that a ...

1981-12-01

289

The inhibition of tumor cell intravasation and subsequent metastasis through the regulation of in vivo tumor cell motility by the tetraspanin CD151  

UK PubMed Central (United Kingdom)

SummaryIn vivo tumor cell migration through integrin-dependent pathways is key to the metastatic behavior of malignant cells. Using quantitative in vivo...Full Text Available

2008-03-01

290

Subcellular Localization of Expansin mRNA in Xylem Cells12  

UK PubMed Central (United Kingdom)

Terminal differentiation of many vascular cells involves cell wall changes. Cells first elongate their primary wall, then lay down a lignified secondary wall, which is often followed by digestion of...Full Text Available

2000-06-01

291

Regulation of asymmetric cell division in the epidermis  

UK PubMed Central (United Kingdom)

For proper tissue morphogenesis, cell divisions and cell fate decisions must be tightly and coordinately regulated. One elegant way to accomplish this is to couple them with asymmetric cell divisions....Full Text Available

292

RNA recognition by the embryonic cell fate determinant and germline totipotency factor MEX-3  

UK PubMed Central (United Kingdom)

Totipotent stem cells have the potential to differentiate into every cell type. Renewal of totipotent stem cells in the germline and cellular differentiation during early embryogenesis rely upon posttranscriptional...Full Text Available

2009-12-01

293

RNA expression in a cartilaginous fish cell line reveals ancient 3? noncoding regions highly conserved in vertebrates  

UK PubMed Central (United Kingdom)

We have established a cartilaginous fish cell line [Squalus acanthias embryo cell line (SAE)], a mesenchymal stem cell line derived from the embryo of an elasmobranch, the spiny dogfish...Full Text Available

2007-01-23

294

Proteome of human colon cancer stem cells: A comparative analysis  

UK PubMed Central (United Kingdom)

AIM: To isolate and identify the biological characteristics of human colon cancer stem cells (SW1116 cells) and further study their proteome.METHODS: SW1116 cells were isolated and cultured with...Full Text Available

2011-03-14

295

Presence of preactivated T cells in hemodialyzed patients: their possible role in altered immunity.  

UK PubMed Central (United Kingdom)

Interleukin 2 (IL-2) and B-cell growth factors I and II (BCGF I and BCGF II) are lymphokines produced by T cells that play a major role in T- and B-cell cooperation. Peripheral blood lymphocytes from...Full Text Available

1986-10-01

297

Onset of Quiescence Following p53 Mediated Down-Regulation of H2AX in Normal Cells  

UK PubMed Central (United Kingdom)

Normal cells, both in vivo and in vitro, become quiescent after serial cell proliferation. During this process, cells can develop immortality with genomic instability,...Full Text Available

298

Nucleoside Drugs Induce Cellular Differentiation by Caspase-Dependent Degradation of Stem Cell Factors  

UK PubMed Central (United Kingdom)

BackgroundStem cell characteristics are an important feature of human cancer cells and play a major role in the therapy resistance of tumours. Strategies to target cancer stem cells...Full Text Available

299

NOTCH3 expression is induced in mural cells through an autoregulatory loop that requires endothelial-expressed JAGGED1  

UK PubMed Central (United Kingdom)

Endothelial cells and mural cells (smooth muscle cells, pericytes, or fibroblasts) are known to communicate with one another. Their interactions not only serve to support fully functional blood...Full Text Available

2009-02-27

300

Muscle satellite cell proliferation and association: new insights from myofiber time-lapse imaging  

UK PubMed Central (United Kingdom)

BackgroundAs the resident stem cells of skeletal muscle, satellite cells are activated by extracellular cues associated with local damage. Once activated, satellite cells will re-enter...Full Text Available

301

Mesenchymal Stem Cells for Craniofacial Tissue Regeneration: Designing Hydrogel Delivery Vehicles  

UK PubMed Central (United Kingdom)

Craniofacial injuries require a variety of different cell types to repopulate areas of bone, cartilage, tendon, and fat. Mesenchymal stem cells (MSCs) provide a multipotent cell source for tissue...Full Text Available

2009-08-01

302

Knockout of Arabidopsis ACCELERATED-CELL-DEATH11 encoding a sphingosine transfer protein causes activation of programmed cell death and defense  

UK PubMed Central (United Kingdom)

We describe the lethal, recessive accelerated-cell-death11 Arabidopsis mutant (acd11). Cell death in acd11 exhibits characteristics of animal apoptosis...Full Text Available

2002-02-15

303

Induced pluripotent stem cells, new tools for drug discovery and new hope for stem cell therapies  

UK PubMed Central (United Kingdom)

Somatic cell nuclear transfer or therapeutic cloning has provided great hope for stem cell-based therapies. However therapeutic cloning has been experiencing both ethical and technical difficulties....Full Text Available

2009-01-01

304

Function of mesenchymal stem cells following loading of gold nanotracers  

UK PubMed Central (United Kingdom)

Background:Stem cells can differentiate into multiple cell types, and therefore can be used for cellular therapies, including tissue repair. However, the participation of stem cells...Full Text Available

2011-01-01

307

Evidence that cell surface heparan sulfate is involved in the high affinity thrombin binding to cultured porcine aortic endothelial cells.  

UK PubMed Central (United Kingdom)

It has been postulated that thrombin binds to endothelial cells through, at least in part, cell surface glycosaminoglycans such as heparan sulfate, which could serve as antithrombin cofactor on the...Full Text Available

1985-04-01

308

Evidence for Diversity in Transcriptional Profiles of Single Hematopoietic Stem Cells  

UK PubMed Central (United Kingdom)

Hematopoietic stem cells replenish all the cells of the blood throughout the lifetime of an animal. Although thousands of stem cells reside in the bone marrow, only a few contribute to blood production...Full Text Available

2006-09-01

312

Cell-density-dependent Changes in the Metabolism of Chloronema Cell Cultures  

UK PubMed Central (United Kingdom)

In the growing chloronema cell suspension cultures of the moss Funaria hygrometrica Hedw., activities of several enzymes have been found to be cell-density-dependent. Cyclic nucleotide...Full Text Available

1979-07-01

313

Cell Polarity Regulator PARD6B Is Essential for Trophectoderm Formation in the Preimplantation Mouse Embryo1  

UK PubMed Central (United Kingdom)

In preimplantation mouse development, the first cell lineages to be established are the trophectoderm (TE) and inner cell mass. TE possesses epithelial features, including apical-basal cell polarity...Full Text Available

2010-09-01

314

3 CFR - Guidelines for Human Stem Cell Research  

Science.gov (United States)

...false Guidelines for Human Stem Cell Research Presidential Documents ...2009 Guidelines for Human Stem Cell Research Memorandum for the Heads...scientifically worthy human stem cell research, including human...

2010-01-01

315

Risk of sperm competition does not influence copulatory behavior in the promiscuous meadow vole (Microtus pennsylvanicus)  

British Library Electronic Table of Contents (United Kingdom)

It is not clear whether males in all mammalian species adjust their copulatory behavior when faced with risk of sperm competition (RSC). Previous work on meadow voles, Microtus pennsylvanicus, indicated that males increase their sperm expenditure but not the number of ejaculations in the presence of odors of a conspecific male. The present study follows up on this work and asks whether male meadow voles modify any aspect of their copulatory behavior when they face a RSC. We examined 46 variables of copulatory behavior and found that the presence of odors from a conspecific male did not affect any of these variables. Thus, male meadow voles, unlike some other species of mammals, do not adjust their copulatory behavior when exposed to cues associated with an elevated RSC.

2007-01-01

316

Risk estimates of liver cancer due to aflatoxin exposure from peanuts and peanut products  

Energy Technology Data Exchange (ETDEWEB)

An assessment was undertaken of the risk of liver cancer in the USA associated with aflatoxin ingestion from peanuts. Both laboratory-animal data and epidemiological data collected from the scientific literature and several prominent mathematical extrapolation techniques were used. Risk estimates differed by a factor of greater than 1000 when the extrapolated results of three selected animal studies were analysed. Dose-response data for the male Fischer rat, the most sensitive mammalian species studied, produced an estimate of 158 cases of liver cancer per year in the USA at current levels of aflatoxin exposure. An estimate of 58 annual cases was predicted on the basis of epidemiological data of populations in Africa and Thailand.

1984-06-01

317

Rapamycin (sirolimus) protects against hypoxic damage in primary heart cultures via Na^+/Ca^2^+ exchanger activation  

British Library Electronic Table of Contents (United Kingdom)

Aims: Rapamycin (sirolimus) is an antibiotic that inhibits protein synthesis through mammalian targeting of rapamycin (mTOR) signaling, and is used as an immunosuppressant in the treatment of organ rejection in transplant recipients. Rapamycin confers preconditioning-like protection against ischemic-reperfusion injury in isolated mouse heart cultures. Our aim was to further define the role of rapamycin in intracellular Ca^2^+ homeostasis and to investigate the mechanism by which rapamycin protects cardiomyocytes from hypoxic damage. Main methods: We demonstrate here that rapamycin protects rat heart cultures from hypoxic-reoxygenation (H/R) damage, as revealed by assays of lactate dehydrogenase (LDH) and creatine kinase (CK) leakage to the medium, by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-d...

2011-01-01

318

Molecular Characterization of Coprophilous Fungal Communities Reveals Sequences Related to Root-Associated Fungal Endophytes  

British Library Electronic Table of Contents (United Kingdom)

This paper reports the use of molecular methods to characterize the coprophilous fungal communities (CFC) that inhabit the dung of four species of mammalian herbivores at two sites, Sevilleta National Wildlife Refuge (SNWR) in New Mexico and Wind Cave National Park (WCNP) in South Dakota. Results reveal that CFC from domesticated cattle (Bos taurus) at SNWR, and bison (Bison bison) and black-tailed prairie dogs (Cynomys ludovicianus) at WCNP were diverse but dominated primarily by members within eight taxonomic orders, including the rarely cultured and anaerobic order Neocallimastigales. In addition, 7.7% (138 of 1,788) of the sequences obtained from all dung samples were at least 97% similar to root-associated fungal (RAF) sequences previously described from blue grama (Bouteloua gracilis...

2011-01-01

319

Health effects  

International Nuclear Information System (INIS)

The main objectives of research in the field of health effects at the Belgian Nuclear Research Centre SCK-CEN are: (1) to study cancer mortality and morbidity in nuclear workers in Belgium; (2) to document the feasibility of retrospective cohort studies in Belgium; (3) to participate in the IARC study; (4) to elucidate the mechanisms of the effects of ionizing radiation on the mammalian embryo during the early phases of its development; (5) to assess the genetic risks of material exposure to ionizing radiation; (6) to elucidate the cellular mechanisms leading to brain damage after prenatal irradiation; (7) to advise authorities and to provide the general population with adequate information concerning the health risk arising from radiation exposure. Progress and major achievements in these topical areas for 1997 are reported.

320

Enamel-Calibrated Lamellar Bone Reveals Long Period Growth Rate Variability in Humans  

British Library Electronic Table of Contents (United Kingdom)

Abstract Mammalian teeth exhibit incremental structures representing successive forming fronts of enamel at varying time scales, including a short daily increment called a cross striation and a long period called a stria of Retzius, the latter of which, in humans, occurs on average every 8-9 days. The number of daily increments between striae is called the repeat interval, which is the same period as that required to form one increment of bone, i.e. the lamella, the fundamental - if not archetypal - unit of bone. Lamellae of known formation time nevertheless vary in width, and thus their measures provide time-calibrated growth rate variability. We measured growth rate variability for as many as 6 years of continuously forming primary incremental lamellar bone from midshaft femur histologic...

2011-01-01

321

Biological effects of electromagnetic radiation in the microwave range  

Energy Technology Data Exchange (ETDEWEB)

The book examines current experimental and clinical knowledge concerning the biological and biophysical effects of electromagnetic radiation, particularly that in the microwave range. The biophysical bases of the interaction of electromagnetic radiation with matter are reviewed with emphasis on biological systems, and the effects of radiation on critical biological systems, including the nervous, reproductive, visual and blood-forming systems are compared. Data concerning the lethal effects of nonionizing radiation is presented and characteristics of the effects of electromagnetic radiation on the whole mammalian organisms are examined. Various reactions of the neuroendocrine system to electromagnetic radiation are described, with particular attention given to the adrenal system, and the combined effects of ionizing and microwave radiation in the flight environment are discussed. Results are also presented of a series of animal experiments on the quantitative ...

1980-01-01

322

Basic Information | Fuel Cells &  

Wastenet

...Basic Information | Fuel Cells & Vehicles | US EPA This web page provides basic information on EPA's Fuel Cells & Vehicles web site ...including the chemical composition of fuel cell technology, how it works, descriptions of the various types of fuel cells , their availability and ... background,electrochemical,hydrogen,fuel cell,fuel cell vehicle,fuel reformer,performace,improved fuel economy,increased engine efficiency,lower emissions,zero emissions,availablity,fuel cell types,diagram,Proton ...Exchange Membrane,PEM Basic Information | Fuel Cells & Vehicles | US EPA background,electrochemical,hydrogen,fuel cell,fuel cell vehicle,fuel reformer,performace,improved fuel economy,...

324

Stem Cell Research Policy Lesson Plan  

Science.gov (United States)

Students get a background on Stem Cell technology and learn to write an effective opinion essay.

2007-09-25

325

Solar-cell airplane Solair 1  

Energy Technology Data Exchange (ETDEWEB)

The article describes the Solair 1 solar cell-powered aircraft. Measures to reduce the weight of the craft are cited.

1983-03-01

326

Laser-assisted solar cell metallization processing. Quarterly report, December 1984-February 1985  

Energy Technology Data Exchange (ETDEWEB)

Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are investigated, developed, and characterized. The tasks comprising these investigations are outlined. A new batch of solar cells was processed using the laser decomposition of spun-on silver neodecanoate to metallize cells. Decomposition of silver neodecanoate was carried out at different laser powers on different cells on a given wafer to determine whether this would have any effect on cell performance. Solar cells which were written with laser powers of 5 to 8 watts, gave excellent results with cell efficiencies in the range of 14 to 16%.

1985-04-04

327

Heavy Metals Effect on Animal Cells  

International Science & Technology Center (ISTC)

Studies of the Superheavy-metal Effect as a Stress-factor on Protein Biosynthesis and Cytoskeleton Integrity in Animal Cells

328

A NEW FORM OF SOLID STATE SOLAR GENERATOR  

Science.gov (United States)

... nent to the design and construction of metal-semiconductor solar cells, in that both the photovoltage and the efficiency of metal-semiconductor cells ...

1962-01-01

329

Establishment and Maintenance of Human Embryonic Stem Cell Lines on Human Feeder Cells Derived from Uterine Endometrium ...  

Science.gov (United States)

... and pathogen transmission. Because the ultimate object of stem cell research is cell-based clinical therapy, hES cells should ... 4%) Supported by grants (SC12021 and SC11012) from Stem Cell Research...

330

Bortezomib induces apoptosis in T lymphoma cells and natural killer lymphoma cells independent of Epstein-Barr virus infection  

British Library Electronic Table of Contents (United Kingdom)

Abstract Epstein-Barr virus (EBV), which infects not only B cells, but also T cells and natural killer (NK) cells, is associated with multiple lymphoid malignancies. Recently, the proteasome inhibitor bortezomib was reported to induce apoptosis of EBV-transformed B cells. We evaluated the killing effect of this proteasome inhibitor on EBV-associated T lymphoma cells and NK lymphoma cells. First, we found that bortezomib treatment decreased the viability of multiple T and NK cell lines. No significant difference was observed between EBV-positive and EBV-negative cell lines. The decreased viability in response to bortezomib treatment was abrogated by a pan-caspase inhibitor. The induction of apoptosis was confirmed by flow cytometric assessment of annexin V staining. Additionally, cleavage o...

2011-01-01

331

Molecular cloning of chicken metallothionein. Deduction of the complete amino acid sequence and analysis of expression using cloned cDNA  

Energy Technology Data Exchange (ETDEWEB)

A cDNA library was constructed using RNA isolated from the livers of chickens which had been treated with zinc. This library was screened with a RNA probe complementary to mouse metallothionein-I (MT), and eight chicken MT cDNA clones were obtained. All of the cDNA clones contained nucleotide sequences homologous to regions of the longest (375 bp) cDNA clone. The latter contained an open reading frame of 189 bp, and the deduced amino acid sequence indicates a protein of 63 amino acids of which 20 are cysteine residues. Amino acid composition and partial amino acid sequence analyses of purified chicken MT protein agreed with the amino acid composition and sequence deduced from the cloned cDNA. Amino acid sequence comparison establish that chicken MT shares extensive homology with mammalian MTs. Southern blot analysis of chicken DNA indicates that the chicken MT gene is not a part of a large family of related sequences, but rather is likely to be a unique gene ...

1988-01-25

332

Fission-track age of a bentonitized ash bed and mammalian fauna from Nagrota formation (Upper Siwalik) of Jammu District, J and K, India  

International Nuclear Information System (INIS)

Fission-track age of a bentonitized volcanic ash bed occurring in the middle part of Nagrota Formation. Upper Siwalik, north of Uttarbaini, Jammu district, Jammu and Kashmir, has been determined to be 1.6 #+-# 0.2 m.y. B.P. The radiometric age obtained for the sample roughly coincides with the Olduvai Event (1.6-1.8 m.y.). However, the lithological and paleoclimatic changes in the Upper Siwalik success ion are indicated at the contact between Parmandal Sandstone and Nagrota Formation, i.e. about 1100 m below the 1.6 #+-# 0.2 m.y. datum line in this part. Vertebrat e fauna was studied from 16 sites beneath and 12 above the volcanic ash bed to interpret the biological and palaeoenvironmental aspects of the Nagrota Formation. The assemblage represented in the collection is similar to that of the Pinjor Biozone (Villafranchian) and is assigned a probable age ranging from about 2.9 m.y. to 1.0 m.y. B.P. The stratigraphic interval from the base of Nagrota Formation (approx. 2.9 m.y. B.P.) to ...

333

Convoluted cells as a marker for maternal cell contamination in CVS cultures  

DEFF Research Database (Denmark)

In order to identify cells of maternal origin in CVS cultures, tissue from 1st trimester abortions were cultivated and the cultures stained in situ for X-chromatin. Convoluted cells and maternal fibroblasts were found to be positive. By chromosome analysis of cultures from 105 diagnostic placenta biopsies, obtained by the transabdominal route, metaphases of maternal origin were found in nine cases. In eight of these cases colonies of convoluted cells were observed. We conclude that convoluted cells are of maternal origin and are a reliable marker for maternal cell contamination in CVS cultures.

1987-01-01

334

Two subpopulations of stem cells for T cell lineage  

Energy Technology Data Exchange (ETDEWEB)

An assay system for the stem cell that colonizes the thymus and differentiates into T cells was developed, and by using this assay system the existence of two subpopulations of stem cells for T cell lineage was clarified. Part-body-shielded and 900-R-irradiated C57BL/6 (H-2b, Thy-1.2) recipient mice, which do not require the transfer of pluripotent stem cells for their survival, were transferred with cells from B10 X Thy-1.1 (H-2b, Thy-1.1) donor mice. The reconstitution of the recipient's thymus lymphocytes was accomplished by stem cells in the donor cells and those spared in the shielded portion of the recipient that competitively colonize the thymus. Thus, the stem cell activity of donor cells can be evaluated by determining the proportion of donor-type (Thy-1.1+) ...

1985-11-01

335

Telomerase-immortalized non-malignant human prostate epithelial cells retain the properties of multipotent stem cells  

International Nuclear Information System (INIS)

Understanding prostate stem cells may provide insight into the origin of prostate cancer. Primary cells have been cultured from human prostate tissue but they usually survive only 15-20 population doublings before undergoing senescence. We report here that RC-170N/h/clone 7 cells, a clonal cell line from hTERT-immortalized primary non-malignant tissue-derived human prostate epithelial cell line (RC170N/h), retain multipotent stem cell properties. The RC-170N/h/clone 7 cells expressed a human embryonic stem cell marker, Oct-4, and potential prostate epithelial stem cell markers, CD133, integrin #alpha#2#beta#1"h"i and CD44. The RC-170N/h/clone 7 cells proliferated in KGM and Dulbecco's Modified Eagle Medium with 10% fetal bovine serum and 5 #mu#g/ml insulin (DMEM + 10% FBS + Ins.) ...

2008-01-01

336

In vitro atrazine-exposure inhibits human natural killer cell lytic granule release  

British Library Electronic Table of Contents (United Kingdom)

The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesized that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test t...

2007-01-01

337

Immunoselection and clinical use of T regulatory cells in HLA-haploidentical stem cell transplantation  

British Library Electronic Table of Contents (United Kingdom)

Introduction: Haploidentical transplantation, with extensive T cell depletion to prevent GvHD, is associated with a high incidence of infection-related deaths. The key challenge is to improve immune recovery with allogeneic donor T cells without triggering GvHD. As T regulatory cells (Tregs) controlled GvHD in pre-clinical studies, the present study evaluated the impact of an infusion of donor CD4/CD25 + Tregs, followed by an inoculum of donor mature T cells (Tcons) and positively immunoselected CD34 + cells in the setting of haploidentical stem cell transplantation. Patients and methods: Twenty-eight patients were enrolled in this study (22 AML; 5 ALL; 1 NHL). All received immunoselected Tregs (CliniMACS, Miltenyi Biotec) followed by positively immunoselected CD34 + cells together with Tc...

2011-01-01

338

The mitogenic activity of human T-cell leukemia virus type I is T-cell associated and requires the CD2/LFA-3 activation pathway.  

UK PubMed Central (United Kingdom)

The presence of a high number of activated T cells in the bloodstream and spontaneous proliferation of peripheral blood mononuclear cells in vitro are striking characteristics of human T-cell leukemia...Full Text Available

1993-06-01

339

Solar cells  

Energy Technology Data Exchange (ETDEWEB)

The article is the second part of a review dealing with latest developments in the area of solar cell technologies and application. Physical principles, design and efficiency as well as advantages and disadvantages of GaAs- and CdS-solar cells are described. Power generation solar cell systems with voltage converters, combined solar cell/solar collector systems and thermoelectric solar systems are presented in the second part of the article.

1983-04-01

340

In vitro atrazine-exposure inhibits human natural killer cell lytic granule release  

International Nuclear Information System (INIS)

The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesized that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test this hypothesis, flow cytometry ...

2007-06-01

341

Improved Mobilization of the CD34+ and CD133+ Bone Marrow-Derived Circulating Progenitor Cells by Freshly Isolated Intracoronary Bone Marrow Cell Transplantation in Patients with Ischemic Heart Disease  

UK PubMed Central (United Kingdom)

Cell therapy is a promising novel option for treatment of cardiovascular disease. Because the role of bone marrow-derived circulating progenitor cells (BM-CPCs) after cell therapy is less clear, we...Full Text Available

2011-09-01

342

Identification of a nuclear-localized nuclease from wheat cells undergoing programmed cell death that is able to trigger DNA fragmentation and apoptotic morphology on nuclei from human cells  

UK PubMed Central (United Kingdom)

PCD (programmed cell death) in plants presents important morphological and biochemical differences compared with apoptosis in animal cells. This raises the question of whether PCD arose independently...Full Text Available

2006-08-01

343

Expression of alternatively spliced human T-lymphotropic virus type I pX mRNA in infected cell lines and in primary uncultured cells from patients with adult T-cell leukemia/lymphoma and healthy carriers.  

UK PubMed Central (United Kingdom)

Although human T-cell lymphotropic virus type I (HTLV-I) is the etiologic agent of adult T-cell leukemia/lymphoma (ATL), the role of viral gene expression in the progression to and maintenance of the...Full Text Available

1992-04-01

344

CD5 Is Dissociated from the B-Cell Receptor in B Cells from Bovine Leukemia Virus-Infected, Persistently Lymphocytotic Cattle: Consequences to B-Cell Receptor-Mediated Apoptosis  

UK PubMed Central (United Kingdom)

Bovine leukemia virus (BLV), a retrovirus related to human T-cell leukemia virus types 1 and 2, can induce persistent nonneoplastic expansion of the CD5+ B-cell population, termed...Full Text Available

2001-02-01

345

Basic study of solid oxide fuel cells. Part 5: investigation of fuel cell materials  

Energy Technology Data Exchange (ETDEWEB)

Solid Oxide Fuel Cell (SOFC) is expected as a new power generation source. The development of SOFC is being conducted by CRIEPI, and so far several reports of the reults were presented. This report examines materials of SOFC. For the purpose, cells were made using some of typical materials and manufacturing processes, and cell performance tests were carried out.

1991-01-01

346

Wafer and Solar Cell Characterization by GT-PVSCAN6000  

Science.gov (United States)

The PVSCAN is an instrument designed to characterize silicon solar cell materials and devices. It performs a host of measurements that yield spatial maps of dislocation density, grain distribution, reflectance, and photoresponses from near-junction and the bulk of a solar cell.

2002-08-01

347

Uptake and Intracellular Activity of Moxifloxacin in Human Neutrophils and Tissue-Cultured Epithelial Cells  

UK PubMed Central (United Kingdom)

The penetration by moxifloxacin of human neutrophils (polymorphonuclear leukocytes [PMN]) and tissue-cultured epithelial cells (McCoy cells) was evaluated by a fluorometric assay. At...Full Text Available

1999-01-01

348

Synovial cells are potent antigen-presenting cells for superantigen, staphylococcal enterotoxin B (SEB).  

UK PubMed Central (United Kingdom)

There is ample evidence suggesting that superantigens may act as a triggering factor in the pathogenesis of rheumatoid arthritis (RA). We investigated whether superantigen could activate T cells in...Full Text Available

1995-03-01

349

Structure of Natural Killer Cell Receptor KLRG1 Bound to E-Cadherin Reveals Basis for MHC-Independent Missing Self Recognition  

UK PubMed Central (United Kingdom)

SUMMARYThe cytolytic activity of natural killer (NK) cells is regulated by inhibitory receptors that detect the absence of self molecules on target cells. Structural studies of...Full Text Available

2009-07-17

350

Stem Cell Research Policies around the World  

UK PubMed Central (United Kingdom)

The proliferation of stem cell research, conflated with its ethical and moral implications, has led governments to attempt regulation of both the science and funding of stem cells. Due to a diversity...Full Text Available

2009-09-01

351

Stem Cell Research (Updated July 26, 2002).  

Science.gov (United States)

Embryonic stem cells have the ability to develop into virtually any cell in the body, and may have the potential to treat medical conditions such as diabetes and Parkinsons disease. On August 9, 2001, President Bush announced that for the first time feder...

2002-01-01

352

Squamous Cell Carcinoma in South-Eastern Equatorial Rain Forest in Calabar, Nigeria  

UK PubMed Central (United Kingdom)

Background: In North America and Europe, 80% of invasive skin cancers are basal cell carcinoma while 20% are squamous cell carcinoma (SCC). In contrast, African studies reveal a preponderance...Full Text Available

353

Spindle cell carcinoma of head and neck: an immunohistochemical and molecular approach to its pathogenesis  

UK PubMed Central (United Kingdom)

BackgroundSpindle cell carcinoma (SpCC) is a rare microscopic type of cancer of the mouth and oropharynx. Although SpCC is thought to arise from squamous cell carcinoma (SCC), it...Full Text Available

2007-05-01

354

Shield-verification survey of a large hot cell at the FFTF  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a radiation shield verification survey of a large hot cell at the Fast Flux Test Facility (FFTF). The following aspects of the shield test are discussed: description of the FFTF; description of the hot cell; the test procedures; radiation protection, and the test results.

1980-01-01

355

SELF-RENEWAL AND DIFFERENTIATION OF MOUSE EMBRYONIC STEM CELLS AS MEASURED BY Oct4 GENE EXPRESSION: EFFECTS OF LIF, ...  

Science.gov (United States)

... from Dr. Austin Smith of the Institute for Stem Cell Research, University of Edinburgh) was modified from the CGR8 ... to thank Dr. Austin Smith, the Institute for Stem Cell Research, University of Edinbu...

356

SAMHD1: a new insight into HIV-1 restriction in myeloid cells  

UK PubMed Central (United Kingdom)

Human myeloid-lineage cells are refractory to HIV-1 infection. The Vpx proteins from HIV-2 and sooty mangabey SIV render these cells permissive to HIV-1 infection through proteasomal degradation of...Full Text Available

357

Results of Source Emissions Testing. UTC Fuel Cell Model ...  

Science.gov (United States)

... Results of Source Emissions Testing UTC Fuel Cell Model PC25C ... Results of Source Emissions Testing: UTC Fuel Cell Model PC25C ...

2004-09-01

358

Regulation of G1 Cell Cycle Progression  

UK PubMed Central (United Kingdom)

Most genetic changes that promote tumorigenesis involve dysregulation of G1 cell cycle progression. A key regulatory site in G1 is a growth factor–dependent restriction point (R) where cells...Full Text Available

2010-11-01

359

Rapamycin inhibits trypanosome cell growth by preventing TOR complex 2 formation  

UK PubMed Central (United Kingdom)

Target of rapamycin (TOR) kinases control cell growth through two functionally distinct multiprotein complexes. TOR complex 1 (TORC1) controls temporal cell growth and is sensitive to rapamycin, whereas...Full Text Available

2008-09-23

360

Progress with Nonhuman Primate Embryonic Stem Cells1  

Science.gov (United States)

... based, disease treatment remains promising, the emphasis for stem cell research from the biomedical research community is clear, and ... diagnosis as a novel source of embryos for stem cell research. Repr...

361

Programmed cell death in castor bean endosperm is associated with the accumulation and release of a cysteine endopeptidase from ricinosomes  

UK PubMed Central (United Kingdom)

The cells of the endosperm of castor bean seeds (Ricinus communis) undergo programmed cell death during germination, after their oil and protein reserves have been mobilized. Nuclear...Full Text Available

1999-11-23

362

Production of placental alkaline phosphatase (PLAP) and PLAP-like material by epithelial germ cell and non-germ cell tumours in vitro.  

UK PubMed Central (United Kingdom)

Placental and placental-like alkaline phosphatase (PLAP) levels in the culture media of 87 cell lines of neoplastic and 'normal' origin were measured by a conventional immunosorbent enzymatic assay...Full Text Available

1994-02-01

363

Product toxicity and cometabolic competitive inhibition modeling of chloroform and trichloroethylene transformation by methanotrophic resting cells.  

UK PubMed Central (United Kingdom)

The rate and capacity for chloroform (CF) and trichloroethylene (TCE) transformation by a mixed methanotrophic culture of resting cells (no exogenous energy source) and formate-fed cells were measured....Full Text Available

1991-04-01

364

Pressure Probe Technique for Measuring Water Relations of Cells in Higher Plants 1  

UK PubMed Central (United Kingdom)

A new method is described for continuously measuring cell turgor pressure (P), hydraulic conductivity (Lp), and volumetric elastic modulus (ε) in higher plant cells, using a pressure...Full Text Available

1978-02-01

365

Ophthalmic abnormalities in patients with cutaneous T-cell lymphoma.  

UK PubMed Central (United Kingdom)

PURPOSE: To determine the frequency of ophthalmic abnormalities in patients with cutaneous T-cell lymphoma (mycosis fungoides and Sézary syndrome) and T-cell lymphoma involving the skin and...Full Text Available

1998-01-01

366

Neutral endopeptidase inhibits prostate cancer cell migration by blocking focal adhesion kinase signaling  

UK PubMed Central (United Kingdom)

Neutral endopeptidase 24.11 (NEP, CD10) is a cell-surface enzyme expressed by prostatic epithelial cells that cleaves and inactivates neuropeptides implicated in the growth of androgen-independent prostate...Full Text Available

2000-12-01

367

Model for phase III autografts of epidermal cells cultured on a collagen-proteoglycan biomatrix.  

UK PubMed Central (United Kingdom)

The primary aim of this study was to develop a model system that uses epidermal cells (keratinocytes and accessory pigmented cells) cultured on a reconstituted basement membrane biomatrix for use in...Full Text Available

1989-10-01

368

Method of restoring degraded solar cells  

Energy Technology Data Exchange (ETDEWEB)

Amorphous silicon solar cells have been shown to have efficiencies which degrade as a result of long exposure to light. Annealing such cells in air at a temperature of about 200.degree. C. for at least 30 minutes restores their efficiency.

1983-01-01

369

Mechanoreceptor Cells on the Tertiary Pulvini of Mimosa pudica L.  

UK PubMed Central (United Kingdom)

Special red cells were found on the adaxial surface of tertiary pulvini of Mimosa pudica and experiments performed to determine the origin and function of these cells. Using anatomical...Full Text Available

2007-11-01

370

Loss of red cell chemokine scavenging promotes transfusion-related lung inflammation  

UK PubMed Central (United Kingdom)

Red cell transfusions are associated with the development of acute lung injury in the critically ill. Recent evidence suggests that storage induced alterations of the red blood cell (RBC) collectively...Full Text Available

2009-01-29

371

Light-induced Adhesion of Spirogyra Cells to Glass 1  

UK PubMed Central (United Kingdom)

Adhesion of Spirogyra (tentatively, Spirogyra fluviatilis) cells to glass is described. The cells of an algal filament can adhere to a substrate only when they are...Full Text Available

1977-04-01

372

Iron Overload, Hematopoietic Cell Transplantation, and Graft-versus-Host Disease  

UK PubMed Central (United Kingdom)

Many patients who undergo hematopoietic cell transplantation (HCT) present with anemia and have received red blood cell transfusions before HCT. As a result, iron overload is frequent and appears...Full Text Available

2009-10-01

373

Identification of the Neoplastically Transformed Cells in Marek's Disease Herpesvirus-Induced Lymphomas: Recognition by the Monoclonal Antibody AV37  

UK PubMed Central (United Kingdom)

Understanding the interactions between herpesviruses and their host cells and also the interactions between neoplastically transformed cells and the host immune system is fundamental to understanding...Full Text Available

2002-07-01

374

Identification of a stem cell candidate in the normal human prostate gland  

UK PubMed Central (United Kingdom)

Stem cells of the human prostate gland have not yet been identified utilizing a structural biomarker. We have discovered a new prostatic epithelial cell phenotype-expressing cytokeratin 6a (Ck6a+...Full Text Available

2005-03-01

375

Human hair genealogies and stem cell latency  

UK PubMed Central (United Kingdom)

BackgroundStem cells divide to reproduce themselves and produce differentiated progeny. A fundamental problem in human biology has been the inability to measure how often stem cells...Full Text Available

376

Human Cloning  

Science.gov (United States)

... is known as "reproductive cloning." The Link to Stem Cell Research Stem cell research and research cloning are closely linked. Scientists in ... to arrive at a position on cloning and stem cell research. Many nations, including the UK, China, and South ...

377

Hepatocyte entry leads to degradation of autoreactive CD8 T cells  

UK PubMed Central (United Kingdom)

Although most self-reactive T cells are eliminated in the thymus, mechanisms to inactivate or control T cells specific for extrathymic antigens are required and exist in the periphery. By investigating...Full Text Available

2011-10-04

378

Glycolipids of human primary testicular germ cell tumours.  

UK PubMed Central (United Kingdom)

The glycolipid content of human non-seminomatous germ cell tumour cell lines correlates with their differentiation lineage. To analyse whether this reflects the situation in primary tumours, we studied...Full Text Available

1996-07-01

379

Germ cell sex determination in mammals  

UK PubMed Central (United Kingdom)

One of the major decisions that germ cells make during their development is whether to differentiate into oocytes or sperm. In mice, the germ cells’ decision to develop as male or female depends...Full Text Available

2009-04-01

380

Genetic heterogeneity in human T-cell leukemia/lymphoma virus type II.  

UK PubMed Central (United Kingdom)

DNA from the peripheral blood mononuclear cells of 17 different individuals infected with human T-cell lymphoma/leukemia virus type II (HTLV-II) was successfully amplified by the polymerase chain reaction...Full Text Available

1993-03-01

381

Experimental attempt to produce mRNA transfected dendritic cells derived from enriched CD34+ blood progenitor cells  

British Library Electronic Table of Contents (United Kingdom)

It Peripheral blood progenitor enriched CD34+ cells (PBPC) are rather often used as stem cell background in cancer patients following high dose therapy. Keeping in mind that precursor dendritic cells (DCs) originate from haematopoietic progenitor cells, purified CD34+ cells might also serve as starting cells for ex-vivo production of DC. The aim of the present study is to develop a clinical grade procedure for ex-vivo production of DC derived from enriched CD34+ cells. Various concentrations of CD34+ cells were grown in gas-permeable Teflon bags with different serum-free and serum-containing media supplemented with GM-CSF, IL-4, TNF-a, SCF, Flt-3L and INF-a. Serum-free CellGroSCGM medium for 7 days followed by CellGroDC medium in 7 days gave equal results as serum-containing ...

2008-01-01

382

Exceptional sensitivity of testicular germ cell tumour cell lines to the new anti-cancer agent, temozolomide.  

UK PubMed Central (United Kingdom)

Metastatic testicular germ cell tumours are cured in approximately 85% of patients using cisplatin-based combination chemotherapy. Patients who fail to respond have a poor prognosis, and there is a...Full Text Available

1995-05-01

383

Establishment of trophectoderm and inner cell mass lineages in the mouse embryo  

UK PubMed Central (United Kingdom)

The first cell lineage specification in mouse embryo development is the formation of trophectoderm (TE) and inner cell mass (ICM) of the blastocyst. This article is to review and discuss the...Full Text Available

2009-11-01

384

Establishment and expression of cellular polarity in fucoid zygotes.  

UK PubMed Central (United Kingdom)

Zygotes of fucoid algae have long been studied as a paradigm for cell polarity. Polarity is established early in the first cell cycle and is then expressed as localized growth and invariant cell division....Full Text Available

1992-06-01

385

Energetic constraints on the creation of cell membrane pores by magnetic particles.  

UK PubMed Central (United Kingdom)

Naturally occurring and contaminant ferromagnetic and ferrimagnetic particles have been found within or near cells, and might allow pulsed magnetic fields to create transient cell membrane opening ("pores")....Full Text Available

1996-08-01

386

Effects of ultrafine particles-induced oxidative stress on Clara cells in allergic lung inflammation  

UK PubMed Central (United Kingdom)

BackgroundClara cell protein (CC16), the main secretory product of bronchiolar Clara cells, plays an important protective role in the respiratory tract against oxidative stress and...Full Text Available

387

Effects of Protons and HZE Particles on Glutamate Transport in Astrocytes, Neurons and Mixed Cultures  

Science.gov (United States)

... ions. MATERIALS AND METHODS Cell Culture Culture of NT2/D1 cells was carried out as described previously (18, 19). NT2 cells were plated at a density of 2. ... ...

388

Effects of Perfluorocarbons on surfactant exocytosis and membrane properties in isolated alveolar type II cells  

UK PubMed Central (United Kingdom)

BackgroundPerfluorocarbons (PFC) are used to improve gas exchange in diseased lungs. PFC have been shown to affect various cell types. Thus, effects on alveolar type II (ATII) cells...Full Text Available

2010-01-01

389

Characteristics of early- and late-recruited oxytocin bursting cells at the beginning of suckling in rats.  

UK PubMed Central (United Kingdom)

1. Paired or single recordings of paraventricular and/or supraoptic oxytocin cells at the beginning of suckling in urethane-anaesthetized rats enabled us to study cell recruitment and compare the characteristics...Full Text Available

1988-05-01

390

Cerebellar cell surface antigens of mouse brain.  

UK PubMed Central (United Kingdom)

Reaggregated cells from 6- to 8-day-old mouse cerebella have been used to raise antibodies in rabbits. The interaction of these antibodies with cerebellar cell surface components was assessed by cytotoxicity...Full Text Available

1975-10-01

391

Cells navigate with a local-excitation, global-inhibition-biased excitable network  

UK PubMed Central (United Kingdom)

Cells have an internal compass that enables them to move along shallow chemical gradients. As amoeboid cells migrate, signaling events such as Ras and PI3K activation occur spontaneously on pseudopodia....Full Text Available

2010-10-05

392

Cells involved in the graft-versus host reaction in vitro  

UK PubMed Central (United Kingdom)

The cell types involved in the cellular immune response were studied with the GVH in vitro as a test system. Comparison of the activities of cells of different lymphoid organs in the...Full Text Available

1973-07-01

393

Cell resilience in species lifespans: a link to inflammation?  

UK PubMed Central (United Kingdom)

Species differences in lifespan have been attributed to cellular survival during various stressors, designated here as ‘cell resilience’. In primary fibroblast cultures, cell...Full Text Available

2010-08-01

394

CXCL12-Mediated Guidance of Migrating Embryonic Stem Cell-Derived Neural Progenitors Transplanted into the Hippocampus  

UK PubMed Central (United Kingdom)

Stem cell therapies for neurodegenerative disorders require accurate delivery of the transplanted cells to the sites of damage. Numerous studies have established that fluid injections to the hippocampus...Full Text Available

395

C. elegans as a model for stem cell biology  

UK PubMed Central (United Kingdom)

We review the application of C. elegans as a model system to understand key aspects of stem cell biology. The only bona fide stem cells in C. elegans...Full Text Available

2010-05-01

396

Apoptosis of human seminoma cells upon disruption of their microenvironment.  

UK PubMed Central (United Kingdom)

One of the main obstacles encountered when trying to culture human seminoma (SE) cells in vitro is massive degeneration of the tumour cells. We investigated whether dissociation of tumour tissue, to...Full Text Available

1996-05-01

397

Activation of peripheral blood mononuclear cells in bronchoalveolar lavage fluid from patients with sarcoidosis: visualisation of single cell activation products.  

UK PubMed Central (United Kingdom)

BACKGROUND--Interstitial lung diseases are characterised by the recruitment of mononuclear cells to disease sites where maturation occurs and activation products, including lysozyme (LZM), are released....Full Text Available

1994-11-01

398

Abrogation of E-Cadherin-Mediated Cellular Aggregation Allows Proliferation of Pluripotent Mouse Embryonic Stem Cells in Shake Flask Bioreactors  

UK PubMed Central (United Kingdom)

BackgroundA fundamental requirement for the exploitation of embryonic stem (ES) cells in regenerative medicine is the ability to reproducibly derive sufficient numbers of cells of...Full Text Available

399

A homozygous P86S mutation of the human glucagon receptor is associated with hyperglucagonemia, ? cell hyperplasia, and islet cell tumor  

UK PubMed Central (United Kingdom)

ObjectiveThe goal of the study was to investigate the genetic and molecular basis of a novel syndrome of marked hyperglucagonemia and pancreatic α cell hyperplasia...Full Text Available

2009-11-01

400

A Practical Approach to Genetic Inducible Fate Mapping: A Visual Guide to Mark and Track Cells In Vivo  

UK PubMed Central (United Kingdom)

Fate maps are generated by marking and tracking cells in vivo to determine how progenitors contribute to specific structures and cell types in developing and adult tissue. An advance in this...Full Text Available

401

Potential anti fungal agents. Synthesis and activity of 2-alkylthiopyridine-4-carbothioamides  

Energy Technology Data Exchange (ETDEWEB)

A series of 2-alkylthiopyrine-4-carbothioamides were synthesized, and their anti-fungal potency was tested. The chemical structures were proved by infrared spectroscopy (IR) and {sup 1}H nuclear magnetic resonance ({sup 1}H-NMR) data and by elemental analysis. The minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) assessment were used for the estimation of potential activity in vitro. The study comprising 21 clinical isolates of fungi showed that two compounds exhibited fair inhibitory activity against some yeasts and dermatophytes. Selective fungistatic activity against non-dermatophytes (MIC = 3.12-25.0 {mu}g/mL) was found also in another compound. None of the above compounds showed inhibitory activity against non-dermatophyte filamentous fungi. Microbiological activity of 2-alkylthiopyridine-4-carbothioamides appears to be mainly related to hydrophobicity of alkyl in position 2. (authors). 10 refs., 8 tabs.

1996-05-01

402

NADP Regulates the Yeast GAL Induction System  

Energy Technology Data Exchange (ETDEWEB)

Transcriptional regulation of the galactose-metabolizing genes in Saccharomyces cerevisiae depends on three core proteins: Gal4p, the transcriptional activator that binds to upstream activating DNA sequences (UASGAL); Gal80p, a repressor that binds to the carboxyl terminus of Gal4p and inhibits transcription; and Gal3p, a cytoplasmic transducer that, upon binding galactose and adenosine 5'-triphosphate, relieves Gal80p repression. The current model of induction relies on Gal3p sequestering Gal80p in the cytoplasm. However, the rapid induction of this system implies that there is a missing factor. Our structure of Gal80p in complex with a peptide from the carboxyl-terminal activation domain of Gal4p reveals the existence of a dinucleotide that mediates the interaction between the two. Biochemical and in vivo experiments suggests that nicotinamide adenine dinucleotide phosphate (NADP) plays a key role in the initial induction event.

2008-01-01

403

Effects of paraquat on Escherichia coli: Differences between B and K-12 strains  

Energy Technology Data Exchange (ETDEWEB)

Escherichia coli B and K-12 are equally susceptible to the bacteriostatic effects of aerobic paraquat, but they differed strikingly when the lethality of paraquat was evaluated. E. coli B suffered an apparent loss of viability when briefly exposed to paraquat, whereas E. coli K-12 did not. This difference depended on the ability of the B-strain, but not the K-12 strain, to retain internalized paraquat; the B strain was killed on aerobic tryptic soy-yeast extract plates during the incubation which preceded the counting of colonies. This difference in retention of paraquat between strains was demonstrated by delayed loss of viability, by growth inhibition, and by cyanide-resistant respiration after brief exposure to paraquat, washing, and testing in fresh medium. This difference was also shown by using ({sup 14}C)paraquat. This previously unrecognized difference between E. coli B and K-12 has been the cause of apparently contradictory reports and should lead to some ...

1990-02-01

404

Construction of a human MluI YAC library  

Energy Technology Data Exchange (ETDEWEB)

The authors describe a cloning strategy for the construction of a human genomic library in yeast artificial chromosomes (YACs) based on complete digestion of high-molecular-weight DNA with the infrequently cutting restriction enzyme MluI. Cloning of MluI fragments in the vector pYAC-RC and one subsequent size fractionation by preparative pulsed-field gel electrophoresis yielded a library with average insert sizes of 600 kb. Ninety-seven percent of the colonies were recombinant. An additional size fractionation of MluI fragments prior to ligation had no significant influence on the size of the YACs. The library currently consists of 5000 clones, which is the equivalent of one human genome. Nineteen percent of the YACs were larger than 1.2 Mb. Since smaller MluI fragments are lost during sizing, they also performed cloning without size fractionation. Only 20% of the colonies were recombinant, probably due to unligated vector fragments that were present during the ...

1994-05-01

405

Biosorption of Ni (II) by Schizosaccharomyces pombe: kinetic and thermodynamic studies  

British Library Electronic Table of Contents (United Kingdom)

The potential of the dried yeast, wild-type Schizosaccharomyces pombe, to remove Ni(II) ion was investigated in batch mode under varying experimental conditions including pH, temperature, initial metal ion concentration and biosorbent dose. Optimum pH for biosorption was determined as 5.0. The highest equilibrium uptake of Ni(II) on S. pombe, q e, was obtained at 25??C as 33.8?mg?g?1. It decreased with increasing temperature within a range of 25?50??C denoting an exothermic behaviour. Increasing initial Ni(II) concentration up to 400?mg?L?1 also elevated equilibrium uptake. No more adsorption took place beyond 400?mg?L?1. Equilibrium data fitted better to Langmuir model rather than Freundlich model. Sips, Redlich?Peterson, and Kahn isotherm equations modelled the investigated system with a...

2011-01-01

406

A procedure for batch separation of sup 14 C-hexose from sup 14 C-sucrose  

Energy Technology Data Exchange (ETDEWEB)

This presentation describes a method for separating {sup 14}C-hexose from {sup 14}C-sucrose in extracts of plant tissue. Portions of ethanol extracts are treated with activated charcoal in microcentrifuge tubes. Aliquots are removed, ethanol evaporated and replaced with reaction mixture that phosphorylates hexose (HEPPS, K{sub 2}HPO{sub 4}, Mg(C{sub 2}H{sub 3}O{sub 2}){sub 2}, ovalbumen, Na{sub 2}ATP, yeast hexokinase). After a time course, the hexokinase reaction is stopped (slowed considerably) to minimize effects of contamination enzyme activities. The stopping agent used is lyxose, a nonphosphorylable analogue of glucose. The strong anionic charge of phosphate introduced through the hexokinase action results in binding (> 95%) of hexose-phosphate to anion-exchange resin. Sucrose remains unbound (> 95%) in solution. This batch ion-exchange is performed in microcentrifuge tubes to allow many samples to be processed simultaneously. Recovery of radiolabel in ...

1991-05-01

407

The advancement of stem cells in radiation medicine  

International Nuclear Information System (INIS)

It may result in acute radiation syndrome after body is exposed to ionizing radiation. The one of long-term effects of irradiation injury is leukemia. The bone marrow cells (BMC) transplantation including stem cells is the only effective therapy for acute radiation syndrome patients. Recently, with the advancement of stem cell research that the stem cells have multipotential and can convert each other, it may supply the new stem source for the irradiation injury patients. At the same time with the further research of radioprotective reagents, the hematopoietic stem cells proliferation after irradiation injury is promoted

2003-02-01

408

Review of the application of molecular beam epitaxy for high efficiency solar cell research  

Energy Technology Data Exchange (ETDEWEB)

In the last two years, rapid progress has been made in the energy conversion efficiencies of GaAs solar cells fabricated from molecular beam epitaxy (MBE) material. The efficiencies of cells fabricated from MBE material are now comparable with those fabricated from metal-organic chemical vapor deposition material, even for cells of dimension 2 cmx4 cm. This paper reviews the progress in MBE cell efficiencies. Also discussed is the role oval defects play in GaAs diode and solar cell performance. (orig.).

1991-05-01

409

Recent progress in a-Si solar cells  

Energy Technology Data Exchange (ETDEWEB)

As concern regarding global environmental problems such as the greenhouse effect and acid rain has increased, so too has the demand for commercially viable solar cells as a clean energy source. Interest in amorphous silicon (a-Si) solar cells has been particularly high, due to their low cost. Technological developments in the field of a-Si solar cells are discussed from the viewpoints of fabrication process, materials, and cell structures. Various applications and systems that take advantage of the a-Si solar cell are then introduced. Finally, future prospects are mentioned

1997-04-14

410

Moving toward personalized cell-based interventions for adrenal cortical disorders: Part 2 - Human diseases and tissue engineering  

British Library Electronic Table of Contents (United Kingdom)

Transdifferentiation of an individual's own cells into functional differentiated cells to replace an organ's lost function would be a personalized approach to therapeutics. In this two part series, we will describe the progress toward establishing functional transdifferentiated adrenal cortical cells. In this article (Part 2), we describe the disorders of the adrenal cortex, therefore establishing why there is the need for personalized cell-based therapy for individuals with these disorders. We then present our pilot studies of cell transdifferentiation toward an adrenal cortical fate using genes described in the first article of this pair (Part 1).

2011-01-01

411

Laser-assisted solar cell metallization processing  

Science.gov (United States)

In this contract, Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are being investigated, developed, and characterized. The tasks comprising these investigations are outlined. Four new batches of solar cells were processed, in addition to several test runs on wafers, using the laser decomposition of spun-on silver neodecanoate to metallize cells. Decomposition of silver neodecanoate was carried out at different laser powers on different cells on a given wafer to determine whether this would have any effect on cell performance. A one watt laser power gave an electroplated linewidth of 50 microns , while at 8 watts the line width was 90 microns.

1986-01-01

412

High efficiency GaInP/GaAs tandem solar cells  

Energy Technology Data Exchange (ETDEWEB)

We report on multijunction GaInP/GaAs photovoltaic cells with total-area efficiencies of 29.5% at one-sun concentration and air mass (AM) 1.5 global and 25.7% one-sun, AM0. These values represent the highest efficiencies achieved by any solar cell under these illumination conditions. Three key areas in this technology are identified and discussed: the grid design, front surface passivation of the top cell, and bottom surface passivation of both cells. Aspects of cell design related to its operation under different solar spectra and under concentration are also discussed.

1994-06-30

413

Efficiency of silicon and GaAs concentrator solar cells operated inside integrating cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

The theory for the general case of solar cells operating inside integrating cavity receivers is established. This is applied to the particular case of different configurations of silicon and GaAs cells. The results of the analysis show that a composite system of silicon and GaAs cells manufactured using relatively simple technology could reach an efficiency of 34%. The optimal configuration is that in which the GaAs cells are placed in the directly illuminated area of the receiver and the silicon cells are placed in the indirectly illuminated area of the receiver. (orig.).

1991-06-01

414

tfrsc fa so - NASA Technical Report Server (NTRS)  

Science.gov (United States)

pletely new PW fuel cell model had to be developed for CINDA. Several ...... following linear equation, which is used in the SINDA fuel cell model: ...

415

Yttrium Y 90 Ibritumomab Tiuxetan, Fludarabine, Radiation Therapy, and Donor Stem Cell Transplant in Treating Patients With Relapsed or Refractory Non-Hodgkin's Lymphoma  

Science.gov (United States)

B-cell Chronic Lymphocytic Leukemia; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Waldenstrom Macroglobulinemia

2010-10-12

416

Variation of Mesenchymal Cells in Polylactic Acid Scaffold in an Osteochondral Repair Model  

UK PubMed Central (United Kingdom)

ObjectiveTo achieve osteochondral regeneration utilizing transplantation of cartilage-lineage cells and adequate scaffolds, it is essential to characterize the behavior of transplanted...Full Text Available

2009-12-01

417

Unmasking Stem/Progenitor Cell Properties in Differentiated ...  

Science.gov (United States)

... In addition to changes in BrdU, we also observed transient changes in p63 gene expression in the myoepithelial/stem cell layer. ...

2007-08-01

418

Towards a Synthetic Chloroplast  

UK PubMed Central (United Kingdom)

BackgroundThe evolution of eukaryotic cells is widely agreed to have proceeded through a series of endosymbiotic events between larger cells and proteobacteria or cyanobacteria,...Full Text Available

420

The formation and degradation of Ti-Ag and Ti-Pd-Ag solar cell contacts  

Science.gov (United States)

Ti-Ag and Ti-Pd-Ag solar cell contacts structure and degradation dependence on high temperature and humidity environmental exposure

1970-01-01

422

The Structure of Plant Cell Walls  

UK PubMed Central (United Kingdom)

The molecular structure, chemical properties, and biological function of the xyloglucan polysaccharide isolated from cell walls of suspension-cultured sycamore (Acer pseudoplatanus)...Full Text Available

1973-01-01

423

TARDEC Brief to OnPoint Technologies  

Science.gov (United States)

... Program: Quallion Matrix Design (small cells) - Investigate the feasibly of a hybrid battery matrix composed of small D-sized cells for use in HEVs ...

2007-02-28

424

Strategies to optimize the outcome of children given T-cell depleted HLA-haploidentical hematopoietic stem cell transplantation  

British Library Electronic Table of Contents (United Kingdom)

The most advanced frontier of allogeneic hematopoietic stem cell transplantation (allo-HSCT) is represented by the use of an HLA-partially matched relative as donor. In this type of transplantation, donor-derived natural killer (NK) cells, which are alloreactive towardtoward recipient cells, significantly contribute to the eradication of leukemia blasts. Alloreactive NK cells may also kill host dendritic cells and T lymphocytes, thus preventing graft-versus-host disease and graft rejection, respectively. Sophisticated strategies of adoptive infusion of T-cell lines/clones specific for the most life-threatening pathogens (namely cytomegalovirus, Epstein-Barr virus, Aspergillus and Adenovirus) have been envisaged, and successfully tested in a few pilot trials, to protect the recipient in the...

2011-01-01

425

Stochastic gene expression and its consequences  

UK PubMed Central (United Kingdom)

Gene expression is a fundamentally stochastic process, with randomness in transcription and translation leading to significant cell-to-cell variations in mRNA and protein levels. This variation...Full Text Available

2008-10-17

426

Stickiness to Glass  

UK PubMed Central (United Kingdom)

Conditions were found in which Chlamydomonas reinhardi exhibits a circadian alteration of its cell surface, measured as ability to stick to glass. Under these same conditions the cells...Full Text Available

1979-06-01

427

Role of mast cells in the pathogenesis of hypersensitivity pneumonitis.  

UK PubMed Central (United Kingdom)

To examine the possibility that mast cells have a central role in the pathogenesis of hypersensitivity pneumonitis, 20 patients with this disease were studied with the aim of seeking evidence for mast...Full Text Available

1987-08-01

428

Role of Mast Cells in Early and Delayed Radiation Injury in Rat Intestine  

Science.gov (United States)

... mast cell staining; ref. 16). The severity of structural radiation injury was assessed using a histopathological radiation injury score ... ...

429

Regulatory T cells in human disease and their potential for therapeutic manipulation  

UK PubMed Central (United Kingdom)

Regulatory T cells are proposed to play a central role in the maintenance of immunological tolerance in the periphery, and studies in many animal models demonstrate their capacity to inhibit inflammatory...Full Text Available

2006-05-01

430

Optical Spectroscopy for Noninvasive Monitoring of Stem Cell Differentiation  

UK PubMed Central (United Kingdom)

There is a requirement for a noninvasive technique to monitor stem cell differentiation. Several candidates based on optical spectroscopy are discussed in this review: Fourier transform infrared (FTIR)...Full Text Available

2010-01-01

431

On the spontaneous emergence of cell polarity  

UK PubMed Central (United Kingdom)

Diverse cell polarity networks require positive feedback for locally amplifying distributions of signalling molecules at the plasma membrane1. Additional...Full Text Available

2008-08-14

432

Neural Tissues from the Implanted Stem Cells  

International Science & Technology Center (ISTC)

Morphological, Electrophysiological and Behavioral Investigations of the Nervous Tissue Developed from the Embryonic Matrix Zone Cells of the Dorsolateral Walls of Lateral Ventricles, Implanted into the Lesioned Regions of the Adult Rat's Brain

433

NASA - Pico-Satellite Solar Cell Experiment (PSSC)  

Science.gov (United States)

Jun 10, 2011 ... The PSSC is a picosatellite designed to test the space environment by providing a testbed to gather data on new solar cell technologies.

434

Modeling of batteries and fuel cells; Proceedings of the Symposium, Phoenix, AZ, Oct. 13-19, 1991  

Energy Technology Data Exchange (ETDEWEB)

The present volume on modeling of batteries and fuel cells discusses the significance of the effectiveness factor for flooded porous electrodes, active pore distribution spectroscopy for characterizing porous battery electrodes, the agglomerate model for porous electrodes, and dynamic-performance measurements of battery cells for electric vehicles and other applications. Attention is given to mathematical modeling of a primary zinc/air battery, mathematical modeling of Grace Li-TiS2 cells, modeling of electrocrystallization processes in battery systems, and rotating disk electrode studies in molten Li/K carbonate eutectic. Topics addressed include the variability of nickel oxide cathode dissolution in molten carbonate fuel cells, water transport properties of fuel cell ionomers, modeling water content effects in polymer electrolyte fuel cells, and computer ...

1991-01-01

435

Misfolded Proteins and Retinal Dystrophies  

UK PubMed Central (United Kingdom)

Many mutations associated with retinal degeneration lead to the production of misfolded proteins by cells of the retina. Emerging evidence suggests that these abnormal proteins cause cell death...Full Text Available

2010-01-01

436

Laser-assisted solar cell metallization processing - NASA ...  

Science.gov (United States)

Oct 15, 1985 ... Title: Laser-assisted solar cell metallization processing. No Digital Version Available: Go to Tips on Ordering ...

437

Large scintillation cells for high sensitivity radon concentration measurements  

Energy Technology Data Exchange (ETDEWEB)

Methods for improving the sensitivity of scintillation cells for radon concentration measurements were studied with emphasis on improving light collection efficiency. This allows the length and hence the volume of the cell to be increased. Variables studied were choice of scintillator material, its method of application and thickness, length of cell, cell material, type and configuration of reflectors, choice of photomultipliers, and factors affecting background. Response from various areas of the cell surface was studied with an alpha source and with radon filling. Coating the window with phosphor was found to be counter-productive. The optimum results obtained were with the inside of the cell (other than the window) covered with a thick layer of ZnS(Ag), or with a thick layer of reflective material coated with a thin layer of phosphor. With it, a 10 cm ...

1983-07-01

438

Large scintillation cells for high sensitivity radon concentration measurements  

International Nuclear Information System (INIS)

Methods for improving the sensitivity of scintillation cells for radon concentration measurements were studied with emphasis on improving light collection efficiency. This allows the length and hence the volume of the cell to be increased. Variables studied were choice of scintillator material, its method of application and thickness, length of cell, cell material, type and configuration of reflectors, choice of photomultipliers, and factors affecting background. Response from various areas of the cell surface was studied with an alphy source and with radon filling. Coating the window with phosphor was found to be counter-productive. The optimum results obtained were with the inside of the cell (other than the window) covered with a thick layer of ZnS(Ag), or with a thick layer of reflective material coated with a thin layer of phosphor. With it, a 10 cm ...

440

Immunohistochemical Analysis of Sarcoid Granulomas  

UK PubMed Central (United Kingdom)

Proliferating cells have been immunophenotypically characterized in lymph node and bronchoalveolar lavage (BAL) samples obtained from patients with active and inactive sarcoidosis with the cell-cycle-related...Full Text Available

1988-05-01

441

Hydrolysis of cis- and trans-Epoxyeicosatrienoic Acids by Rat Red Blood Cells  

UK PubMed Central (United Kingdom)

Erythrocytes serve as reservoirs for cis- and trans-epoxyeicosatrienoic acids (EETs). Incubation of rat red blood cells (RBCs) with cis- and...Full Text Available

2008-07-01

442

Hormonal Control of Cell Proliferation Requires PASTICCINO Genes  

UK PubMed Central (United Kingdom)

PASTICCINO (PAS) genes are required for coordinated cell division and differentiation during plant development. In loss-of-function pas mutants,...Full Text Available

2003-07-01

443

High-Temperature Solar Cell Development - GLTRS - NASA  

Science.gov (United States)

High-Temperature Solar Cell Development. Geoffrey A. Landis,. NASA John Glenn Research Center. 21000 Brookpark Road, Cleveland, OH 44135. Danielle ...

444

General Disclaimer One or more of the Following Statements may ...  

Science.gov (United States)

1 The Elemental Fuel Cell Model. The cell reactions are also illustrated in. Figure 1. Hydrogen is oxidized at the anode. Oxy- ...

445

Expression of cell proliferation and apoptosis biomarkers in pterygia and normal conjunctiva  

UK PubMed Central (United Kingdom)

PurposeTo analyze the expression of apoptosis and cell proliferation molecules in pterygium tissues of Chinese patients.MethodsThirty-three pterygia...Full Text Available

446

Durability of Membrane Electrode Assemblies (MEAs) in PEM Fuel ...  

Science.gov (United States)

Proton exchange membrane (PEM) fuel cells are energy sources that have the ... for H2 /02 PEM fuel cells because their catalysts have properties suitable for 0 ...

447

Dietary Lipids, Cells Adhesion and Breast Cancer Metastasis  

Science.gov (United States)

... Accession Number : ADA396364. Title : Dietary Lipids, Cells Adhesion and Breast Cancer Metastasis. Descriptive Note : Annual rept. ...

2000-10-01

448
450

Continuous human cell lines and method of making same  

Energy Technology Data Exchange (ETDEWEB)

Substantially genetically stable continuous human cell lines derived from normal human mammary epithelial cells (HMEC) and processes for making and using the same. In a preferred embodiment, the cell lines are derived by treating normal human mammary epithelial tissue with a chemical carcinogen such as benzo(a)pyrene. The novel cell lines serve as useful substrates for elucidating the potential effects of a number of toxins, carcinogens and mutagens as well as of the addition of exogenous genetic material. The autogenic parent cells from which the cell lines are derived serve as convenient control samples for testing. The cell lines are not neoplastically transformed, although they have acquired several properties which distinguish them from their normal progenitors. 2 tabs.

1985-07-01

451

Continuity and change  

Science.gov (United States)

... with the loosening of Bush-era restrictions on stem cell research, a move that was widely hailed by the ... The first two explore the contentious debate over stem cell research. Using a series of intervie...

452

Committed T lymphocyte stem cells of rats. Characterization by surface W3/13 antigen and radiosensitivity  

Energy Technology Data Exchange (ETDEWEB)

The existence of stem cells committed to the T lymphoid lineage was deduced from studying how rat T and B stem cells differ in their expression of membrane W3/13 antigen and in their susceptibility in vivo to gamma irradiation. Stem cell activity of rat bone marrow and fetal liver was measured in long-term radiation chimeras using B and T cell alloantigenic surface markers to identify the progeny of donor cells. Monoclonal mouse anti-rat thymocyte antibody W3/13 labeled approximately 40% of fetal liver cells and 60-70% of young rat bone marrow cells (40% brightly, 25% dimly). Bright, dim, and negative cells were separated on a fluorescence-activated cell sorter. All B and T lymphoid stem cells in fetal liver were W3/13 bright, as were B lymphoid stem cells in ...

1981-01-01

453

Cell proliferation and chemical carcinogenesis: symposium overview.  

UK PubMed Central (United Kingdom)

Cancer, by definition, is a proliferative disease. The fundamental scientific issue explored at the international symposium "Cell Proliferation and Chemical Carcinogenesis" was the impact of chemically...Full Text Available

1993-12-01

454

CD44 Occupancy Prevents Macrophage Multinucleation  

UK PubMed Central (United Kingdom)

Cells of the mononuclear phagocyte lineage have the capability to adhere to and fuse with each other and to differentiate into osteoclasts and giant cells. To investigate the macrophage adhesion/fusion...Full Text Available

1998-11-02

455

Analysis of heterogeneous cell populations: A density-based modeling and identification framework  

British Library Electronic Table of Contents (United Kingdom)

Abstract: In many biological processes heterogeneity within clonal cell populations is an important issue. One of the most striking examples is a population of cancer cells in which after a common, identical death signal some cells die whereas others survive. The reason for this heterogeneity is intrinsic and extrinsic noise. In this paper we present a mechanistic multi-scale modeling framework for cell populations, in which the dynamics of every individual cell is captured by a parameter dependent stochastic differential equation (SDE). Heterogeneity among individual cells is accounted for by differences in parameter values, modeling extrinsic influences. Based on the statistical properties of the extrinsic noise and the SDE model for the individual cell, a partial differential equation (...

2011-01-01

456

A sample preparation for quantitative determination of magnesium in individual lymphocytes by electron probe X-ray microanalysis.  

Science.gov (United States)

We present a sample preparation method for measuring magnesium in individual whole lymphocytes by electron probe X-ray microanalysis. We use Burkitt's lymphoma cells in culture as the test sample and compare X-ray microanalysis of individual cells with atomic absorption analysis of pooled cell populations. We determine the magnesium peak-to-local continuum X-ray intensity ratio by electron probe X-ray microanalysis and calculate a mean cell magnesium concentration of 39 +/- 19 mmol/kg dry weight from analysis of 100 cells. We determine a mean cell magnesium concentration of 34 +/- 4 mmol/kg dry weight by atomic absorption analysis of pooled cells in three cell cultures. The mean cell magnesium concentrations determined by the two methods are not significantly different. We find a 10% coefficient of ...

1986-01-01

457

A Theoretical Solid Oxide Fuel Cell Model for - The NASA Glenn ...  

Science.gov (United States)

May 31, 2011 ... A Theoretical Solid Oxide Fuel Cell Model for System Controls and Stability Design AUTHOR(S): Kopasakis, George; Brinson, Thomas; Credle, ...

458

2004 Office of Fossil Energy Fuel Cell Program Annual Report  

Energy Technology Data Exchange (ETDEWEB)

Annual report of fuel cell projects sponsored by Department of Energy, National Energy Technology Laboratory.

2004-11-01

459

20 Watt-Hour Per Pound Regenerative Fuel Cell  

Science.gov (United States)

... for evaluation of the electrochemiral performance of the materials and components used in EOS Rechargeable Fuel Cell Model RHO-24AH-Mod ...

1972-03-01

460

cDNA cloning and sequence analysis of preproendothelin-1 (PPET-1) from salmon, Oncorhynchus keta.  

Science.gov (United States)

The presence of endothelin (ET)-like immunoreactivity and the cardiovascular effects of mammalian ET-1 in fish have been reported. To identify ET-related peptides in fish, we screened the cDNA library of the salmon (Oncorhynchus keta) stomach by means of rapid amplification of cDNA ends, and we cloned cDNAs encoding an ET-related peptide. The salmon ET-related sequence of 21 amino acids is identical to the trout ET-1 peptide recently purified from kidney specimens of Oncorhynchus mykiss. The deduced amino acid sequence of salmon pre-proET-1 (PPET-1) comprises 244 amino acids, including a putative signal sequence and mature ET-1, as well as big ET-1 and ET-1-like sequences. This precursor, the first reported PPET-1 sequence for Salmoniformes, Teleostei, has low homology with the sequences of human, mouse, frog (Xenopus laevis), and zebrafish (Danio rerio) PPET-1 (26%, 29%, 24%, and 39%, respectively). PMID:16740985

2006-06-01

461

Role of the Yersinia pestis Ail Protein in Preventing a Protective Polymorphonuclear Leukocyte Response During Bubonic Plague.  

Science.gov (United States)

The ability of Yersinia pestis to forestall the mammalian innate immune response is a fundamental aspect of plague pathogenesis. In this study, we examined the effect of Ail, a 17-kDa outer membrane protein that protects Y. pestis against complement-mediated lysis, on bubonic plague pathogenesis in mice and rats. The Y. pestis ail mutant was attenuated for virulence in both rodent models. The attenuation was greater in rats than in mice, which correlates with the ability of normal rat serum, but not mouse serum, to kill ail-negative Y. pestis in vitro. Intradermal infection with the ail mutant resulted in an atypical, subacute form of bubonic plague associated with extensive recruitment of polymorphonuclear leukocytes (PMN or neutrophils) to the site of infection in the draining lymph node and the formation of large purulent abscesses that contained the bacteria. Systemic spread and mortality were greatly attenuated, however, and a productive adaptive immune ...

2011-10-01

462

Radioactive-electrophoretic assay of adenosine 5'-triphosphate sulfurylase activity in crude extracts with sulfate or selenate as a substrate  

Energy Technology Data Exchange (ETDEWEB)

An assay method for ATP sulfurylase is presented which employs Na/sub 2/(35)SO/sub 4/ as a substrate and measures the production of labeled adenosine 5'-phosphosulfate and 3'-phosphoadenosine 5'-phosphosulfate by low-voltage, hanging paper strip electrophoresis. The method is applicable to crude bacterial or mammalian extracts and accurately measures picomole amounts of product(s). Na/sub 2/(/sup 75/)SeO/sub 4/ can also be employed as a substrate, if the unstable radioactive product, adenosine 5'-phosphoselenate, is converted to elemental /sup 75/Se degrees by inclusion of reduced glutathione in the reaction mixture. The same paper strip electrophoretic technique can then be used to separate /sup 75/Se degrees from the radiolabeled substrate. The method also has utility for measuring any direct reduction by crude microbial extracts of radioactive selenate to selenite, independent of ATP sulfurylase.

1989-02-01

463

Determination of microsomal lauric acid hydroxylase activity by HPLC with flow-through radiochemical quantitation  

International Nuclear Information System (INIS)

An assay for the microsomal hydroxylation of lauric acid (LA), based on HPLC with flow-through radiochemical detection, has been developed. Conditions were optimized for resolution and quantitation of three microsomal metabolites of "1"4C-LA, one of which has not been reported previously as a metabolite of LA in mammalian microsomal incubations. These products, 12-(omega)-hydroxy-LA, 11-(omega-1)-hydroxy-LA, and a novel metabolite, 10-(omega-2)-hydroxy-LA, were isolated by HPLC and identified by gas chromatography/mass spectrometry. In the presence of NADPH, the formation of all three metabolites was linear with time and microsomal protein concentration. Hydrogen peroxide also supported the microsomal metabolism of LA, although the ratio of metabolites was substantially different than that produced by NADPH-supported microsomes. Several biochemical probes (metyrapone, #alpha#-naphthoflavone, 2-diethylaminoethyl-2,2-diphenylvalerate hydrochloride, and 10-undecynoic ...

464

Cloning and mapping of the mouse {alpha}7-neuronal nicotinic acetylcholine receptor  

Energy Technology Data Exchange (ETDEWEB)

We report the isolation of cDNA clones for the mouse {alpha}7 neuronal nicotinic acetylcholine receptor subunit (gene symbol Acra7), the only nicotinic receptor subunit known to bind a-bungarotoxin in mammalian brain. This gene may have relevance to nicotine sensitivity and to some electrophysiologic findings in schizophrenia. The mouse {alpha}7 subunit gene encodes a protein of 502 amino acids with substantial identity to the rat (99.6%), human (92.8%), and chicken (87.5%) amino acid sequences. The {alpha}7 gene was mapped to mouse chromosome 7 near the p locus with the following gene order from proximal to distal: Myod1-3.5 {+-}1.7 cM-Gas2-0.9 cM {+-} 0.9 cM-D7Mit70-1.8 {+-} 1.2 cM- Acra7-4.4 {+-}1.0 cM-Hras1-ps11/Igf1r/Snrp2a. The human gene was confirmed to map to the homologous region of human chromosome 15q13-q14. 26 refs., 3 figs.

1995-03-20

465

Biological effects after prenatal irradiation (embryo and fetus) ICRP Publication 90 Approved by the Commission in October 2002  

International Nuclear Information System (INIS)

In its 1990 recommendations, the ICRP considered the radiation risks after exposure during prenatal development. This report is a critical review of new experimental animal data on biological effects and evaluations of human studies after prenatal radiation published since the 1990 recommendations. Thus, the report discusses the effects after radiation exposure during pre-implantation, organogenesis, and fetogenesis. The aetiology of long-term effects on brain development is discussed, as well as evidence from studies in man on the effects of in-utero radiation exposure on neurological and mental processes. Animal studies of carcinogenic risk from in-utero radiation and the epidemiology of childhood cancer are discussed, and the carcinogenic risk to man from in-utero radiation is assessed. Open questions and needs for future research are elaborated. The report reiterates that the mammalian embryo and fetus are highly radiosensitive. The nature and sensitivity of ...

466

Avian LH and FSH: comparison of several radioimmunoassays  

Energy Technology Data Exchange (ETDEWEB)

Comparisons were made between various LH and FSH radioimmunoassays currently being used to measure avian hormones. The two LH assays were the homologous chicken system of Follett et al. (1972) and the turkey assay of Burke et al. (1979). These assays were also used in heterologous arrangement by interchanging the iodinated LH fractions and antisera. Five FSH assays were analyzed: two homologous chicken systems (Scanes et al., 1977; Sakai and Ishii, 1980) an assay based on mammalian materials (rat FSH and anti-ovine FSH antiserum, and one using labelled turkey FSH (Burke et al., 1979) with an anti-chicken FSH antiserum. The potencies of purified chicken and turkey gonadotrophin preparations and of a range of plasma samples from Japanese quail were measured in each assay. The two LH systems showed some degree of species specificity, such that chicken LH was more active than turkey LH in the chicken assay, whereas the reverse was true in the turkey LH assay. The ...

1983-04-01

467

Some thoughts on stem cells and carcinogenesis. The thyroid gland  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this review is to consider the hypothesis that cancer frequently originates from stem cells. Using the spleen transplantation assay where stem cells were transplanted in the spleen of mice lethally irradiated by ionizing radiation, the author undertook a study aimed at defining the risk of radiogenic cancer per susceptible cells with use of rat radiogenic mammary and thyroid cancers because of the high incidences of these cancers in a-bomb survivors. Measured were the number of cancer-susceptible cells initially present in the tissue, the number of such cells that survived at a given dose and the number of cancers that developed per surviving cell. Thyroid cell differentiation and proliferation in rats transplanted with thyroid cells were enhanced by thyroidectomy and low iodine diet. Further, the ...

2000-07-01

468

Role of limited cell replicative capacity in pathological age change. A review  

Energy Technology Data Exchange (ETDEWEB)

Physiological functions are carried out by differentiated cells, with finite lifespans, which age and need to be replaced. In young individuals, tissue functions are sustained at optimal levels because cellular dysfunction and cell loss are balanced by the emergence of newly differentiated cells as stem cells and their partially differentiated descendants replicate. However, with the passage of time the mitotic rates of these cells diminish. Eventually, replications occur too infrequently to offset the loss. It is at this point that the tissue begins to show structural changes and declining function which, as they become pervasive, are identified as ageing. In this paper the theory is set forth that: (1) Diminishing mitotic activity in older tissues results from limited stem cell replicative capacity. (2) All stem cells, regardless of ...

1982-01-01

469

Gap-junctional communication of bone marrow stromal cells is resistant to irradiation in vitro  

Energy Technology Data Exchange (ETDEWEB)

Bone marrow is one of the most radiosensitive organs. Irradiation causes a marked decrease in the total number of hematopoietic cells in the bone marrow. The reticular meshwork structure of marrow stromal cells, however, is relatively resistant to irradiation. Unimpaired stromal cell structure has been thought to be a prerequisite for the repopulation of hematopoietic cells during recovery from the effects of irradiation. The reticular framework is maintained by cell adhesion apparatuses such as gap junctions. The in vitro radiobiologic survival values of a cloned stromal cell line, H-1/A, were studied (n = 1.8, D0 = 138 cGy). Radiation doses of up to 4000 cGy had no detectable effects on the production of colony-stimulating factor 1. H-1/A cells communicate with each other via gap junctions as determined by the sensitive dye-transfer ...

1990-10-01

470

Gap-junctional communication of bone marrow stromal cells is resistant to irradiation in vitro  

International Nuclear Information System (INIS)

Bone marrow is one of the most radiosensitive organs. Irradiation causes a marked decrease in the total number of hematopoietic cells in the bone marrow. The reticular meshwork structure of marrow stromal cells, however, is relatively resistant to irradiation. Unimpaired stromal cell structure has been thought to be a prerequisite for the repopulation of hematopoietic cells during recovery from the effects of irradiation. The reticular framework is maintained by cell adhesion apparatuses such as gap junctions. The in vitro radiobiologic survival values of a cloned stromal cell line, H-1/A, were studied (n = 1.8, D0 = 138 cGy). Radiation doses of up to 4000 cGy had no detectable effects on the production of colony-stimulating factor 1. H-1/A cells communicate with each other via gap junctions as determined by the sensitive dye-transfer ...

471

Electric-field-induced deformation of biological cells  

Energy Technology Data Exchange (ETDEWEB)

The cell is modeled as an ellipsoid with shell and the surface stress distribution calculated by means of the Maxwell Stress Tensor. The cell membrane is treated as incompressible material having both bending and shear energies of deformation. Employing the principle of virtual work, cell volume (and hence shape) is computed as a function of the external field strength and orientation with respect to the field. The following results were obtained: (1) The surface stresses that develop or the cell membrane are distributed having both normal and tangential components that act together to produce a rounding of the cell. (2) If the tangential component of the stress is ignored, then higher field strengths are needed to produce similar deformation (shape change) of cells. (3) The threshold value of the applied field, i.e, the field strength at which the volume ...

1989-01-01

472

The Future of Induced Pluripotent Stem Cells for Cardiac Therapy and Drug Development.  

Science.gov (United States)

The field of stem cell research was revolutionized with the advent of induced pluripotent stem cells. By reprogramming somatic cells to pluripotent stem cells, most ethical concerns associated with the use of embryonic stem cells are overcome, such that many hopes from the stem cell field now seem a step closer to reality. Several methods and cell sources have been described to create induced pluripotent stem cells and we discuss their characteristics in terms of feasibility and efficiency. From these cells, cardiac progenitors and cardiomyocytes can be derived by several protocols and most recent advances as well as remaining limitations are being discussed. However in the short time period this technology has been around, evidence emerges that induced pluripotent stem cells may ...

2011-09-15

473

Sex and seasonal differences in the rate of cell proliferation in the dentate gyrus of adult wild meadow voles.  

Science.gov (United States)

In order to study the neurobiological basis of seasonal changes in hippocampal structure and function, the rate of cell proliferation was examined in male and female wild meadow voles captured during different seasons. We found that the number of [3H]thymidine-labeled cells varied across the seasons and across sex in the meadow vole. Non-breeding female meadow voles had a higher rate of cell proliferation and cell death than males captured during either season or breeding females. These seasonal changes in the female meadow vole were associated with both fluctuating levels of adrenal steroids and gonadal steroids. Estradiol level was highly correlated with both the number of [3H]thymidine-labeled cells and the number of pyknotic cells in female meadow voles, with high levels of estradiol being associated with low levels of cell proliferation ...

1999-03-01

474

[Intraspecies antagonism of Sh. flexneri in an HEp-2 cell line model].  

Science.gov (United States)

The authors describe an effect of suppression of invasion of the guinea pig eye conjunctiva and the HEp-2 epithelial cells by virulent Sh. flexneri bacilli, with a simultaneous administration of the same dose of avirulent shigella mutants, genetically connected with them. The data of morphological study and experiments with 3H-glucose labeled shigellae carried out on the cell species model indicated that the bacterial competition for the specific sites for absorption on the epithelial cells underlay the observed phenomenon. PMID:331774

1977-06-01

475

Turgor Regulation in Osmotically Stressed Arabidopsis Epidermal Root Cells. Direct Support for the Role of Inorganic Ion Uptake as Revealed by Concurrent Flux and Cell Turgor Measurements1  

UK PubMed Central (United Kingdom)

Hyperosmotic stress is known to significantly enhance net uptake of inorganic ions into plant cells. Direct evidence for cell turgor recovery via such a mechanism, however, is still lacking. In the...Full Text Available

2002-05-01

476

The AMOS cell - An improved metal-semiconductor solar cell  

Science.gov (United States)

A new fabrication process is being developed which significantly improves the efficiency of metal-semiconductor solar cells. The resultant effect, a marked increase in the open-circuit voltage, is produced by the addition of an interfacial layer oxide on the semiconductor. Cells using gold on n-type gallium arsenide have been made in small areas (0.17 sq cm) with conversion efficiencies of 15% in terrestrial sunlight.

1975-01-01

477

Testing of solar cells for communication satellites  

International Nuclear Information System (INIS)

... cadmium sulfides communications electrons performance testing physical

478

Regulatory T cells inhibit stable contacts between CD4+ T cells and dendritic cells in vivo  

UK PubMed Central (United Kingdom)

Regulatory T (T reg) cells exert powerful down-modulatory effects on immune responses, but it is not known how they act in vivo. Using intravital two-photon laser scanning microscopy we determined that,...Full Text Available

2006-03-20

480

Radiation Protection of the Organism (Selected Chapters)  

Science.gov (United States)

... biologically important compounds is sharply lowered with passage of the solutions to the cell an organ, where their sensitivity ...

1970-12-11

483

Microfluidic systems and methods for transport and lysis of cells and analysis of cell lysate  

Energy Technology Data Exchange (ETDEWEB)

Microfluidic systems and methods are disclosed which are adapted to transport and lyse cellular components of a test sample for analysis. The disclosed microfluidic systems and methods, which employ an electric field to rupture the cell membrane, cause unusually rapid lysis, thereby minimizing continued cellular activity and resulting in greater accuracy of analysis of cell processes.

2008-09-02

489

Human breast cancer cell lines contain stem-like cells that self-renew, give rise to phenotypically diverse progeny and survive chemotherapy  

UK PubMed Central (United Kingdom)

IntroductionThe phenotypic and functional differences between cells that initiate human breast tumors (cancer stem cells) and those that comprise the tumor bulk are difficult to...Full Text Available

2008-01-01

493

Different telomere-length dynamics at the inner cell mass versus established embryonic stem (ES) cells  

UK PubMed Central (United Kingdom)

Murine embryonic stem (ES) cells have unusually long telomeres, much longer than those in embryonic tissues. Here we address whether hyper-long telomeres are a natural property of pluripotent stem cells,...Full Text Available

2011-09-13

498

Amplified B Lymphocyte CD40 Signaling Drives Regulatory B10 Cell Expansion in Mice  

UK PubMed Central (United Kingdom)

BackgroundAberrant CD40 ligand (CD154) expression occurs on both T cells and B cells in human lupus patients, which is suggested to enhance B cell CD40 signaling and play a role...Full Text Available