Science.gov

Sample records for pumpkin cell walls1

  1. Giant Pumpkins

    NASA Astrophysics Data System (ADS)

    Hu, David; Alexeev, Alex

    2009-11-01

    In this combined experimental and theoretical study, we investigate the growth of pumpkins from 1 to 1000 pounds in weight. Time-lapse photography is used to document the growth of pumpkins. Data is presented on the relation between the pumpkins' weights and aspect ratios (height divided by width). We observe pumpkins tend to become squashed (up to 50%) as they increase in size. The lattice-spring method is used to numerically estimate the elasto-plastic forces resisting deformation of the pumpkin. Using levels of plasticity consistent with that of plant cell growth, we find pumpkins shapes consistent with those observed.

  2. Structure of Plant Cell Walls 1

    PubMed Central

    Ishii, Tadashi; Thomas, Jerry; Darvill, Alan; Albersheim, Peter

    1989-01-01

    Considerable information has been obtained about the primary structures of suspension-cultured sycamore (Acer pseudoplatanus) cell-wall pectic polysaccharides, i.e. rhamnogalacturonan I, rhamnogalacturonan II, and homogalacturonan. However, these polysaccharides, which are solubilized from the walls by endo-α-1,4-polygalacturonase, account for only about half of the pectic polysaccharides known to be present in sycamore cell walls. We now report that, after exhaustive treatment with endo-α-1,4-polygalacturonase, additional pectic polysaccharides were extracted from sycamore cell walls by treatment with Na2CO3 at 1 and 22°C. These previously uncharacterized polysaccharides accounted for ∼4% of the cell wall. Based on the glycosyl and glycosyl-linkage compositions and the nature of the products obtained by treating the quantitatively predominant NaCO3-extracted polysaccharides with lithium metal dissolved in ethylenediamine, the polysaccharides were found to strongly resemble rhamnogalacturonan I. However, unlike rhamnogalacturonan I that characteristically had equal amounts of 2- and 2,4-linked rhamnosyl residues in its backbone, the polysaccharides extracted in Na2CO3 at 1°C had markedly disparate ratios of 2- to 2,4-linked rhamnosyl residues. We concluded that polysaccharides similar to rhamnogalacturonan I but with different degrees of branching are present in the walls of suspension-cultured sycamore cells. PMID:16666559

  3. Pumpkin seed extract: Cell growth inhibition of hyperplastic and cancer cells, independent of steroid hormone receptors.

    PubMed

    Medjakovic, Svjetlana; Hobiger, Stefanie; Ardjomand-Woelkart, Karin; Bucar, Franz; Jungbauer, Alois

    2016-04-01

    Pumpkin seeds have been known in folk medicine as remedy for kidney, bladder and prostate disorders since centuries. Nevertheless, pumpkin research provides insufficient data to back up traditional beliefs of ethnomedical practice. The bioactivity of a hydro-ethanolic extract of pumpkin seeds from the Styrian pumpkin, Cucurbita pepo L. subsp. pepo var. styriaca, was investigated. As pumpkin seed extracts are standardized to cucurbitin, this compound was also tested. Transactivational activity was evaluated for human androgen receptor, estrogen receptor and progesterone receptor with in vitro yeast assays. Cell viability tests with prostate cancer cells, breast cancer cells, colorectal adenocarcinoma cells and a hyperplastic cell line from benign prostate hyperplasia tissue were performed. As model for non-hyperplastic cells, effects on cell viability were tested with a human dermal fibroblast cell line (HDF-5). No transactivational activity was found for human androgen receptor, estrogen receptor and progesterone receptor, for both, extract and cucurbitin. A cell growth inhibition of ~40-50% was observed for all cell lines, with the exception of HDF-5, which showed with ~20% much lower cell growth inhibition. Given the receptor status of some cell lines, a steroid-hormone receptor independent growth inhibiting effect can be assumed. The cell growth inhibition for fast growing cells together with the cell growth inhibition of prostate-, breast- and colon cancer cells corroborates the ethnomedical use of pumpkin seeds for a treatment of benign prostate hyperplasia. Moreover, due to the lack of androgenic activity, pumpkin seed applications can be regarded as safe for the prostate. PMID:26976217

  4. Partial Chemical Characterization of Corn Root Cell Walls 1

    PubMed Central

    Dever, John E.; Bandurski, Robert S.; Kivilaan, A.

    1968-01-01

    The present study reports on chemical changes which occur in the cell wall of Zea mays during early phases of growth. Roots of seedling corn plants were divided into a meristematic zone, the zone of elongation, and the maturation zone, and the cell wall isolated from each of these zones. The wall preparations were then extracted sequentially to obtain pectin, hemicellulose, cellulose, and lignin fractions. Each of these, except for the lignin fraction, was hydrolyzed and the resultant sugars isolated, identified, and estimated quantitatively. Quantitative analysis of the products of hydrolysis of these fractions demonstrated that the classical scheme of fractionation is a valuable indicator of the changes in solubility properties which the various polysaccharide components for the wall undergo. It does not however yield definite chemical entities. For example, the “pectin” fraction contains only about 3% galacturonic acid; the bulk of it being composed of glucose, xylose, and galactose. By summation of analysis of these various fractions, it was found that substances yielding glucose and xylose upon hydrolysis increase with advancing age of the tissue. Galactose- and arabinose-yielding compounds decrease and mannose appears during maturation. Anhydrouronic acids first decrease, then increase. Most interestingly, of the total dry weight of the cell wall, only 24, 45, and 50% of the meristematic, elongation, and maturation zones respectively are accounted for as simple sugars in the acid hydrolysates. Oligosaccharides were not encountered in large amounts so that the 50 to 75% of the wall weight unaccounted for would consist of polysaccharides or oligosaccharides not precipitated by ethanol from the extracting solutions employed and by polysaccharides in the hemicellulose fraction which are resistant to acid hydrolysis. PMID:16656735

  5. Pumpkin Batch.

    ERIC Educational Resources Information Center

    Hansen, Karen L.

    1988-01-01

    The pumpkin is the theme for a collection of classroom activities which teachers can integrate into the language arts, science, social studies, math, and art curriculums. Many activities were suggested by classroom teachers. (IAH)

  6. The Big Pumpkin Count.

    ERIC Educational Resources Information Center

    Coplestone-Loomis, Lenny

    1981-01-01

    Pumpkin seeds are counted after students convert pumpkins to jack-o-lanterns. Among the activities involved, pupils learn to count by 10s, make estimates, and to construct a visual representation of 1,000. (MP)

  7. Biochemical and Immunocytological Characterizations of Arabidopsis Pollen Tube Cell Wall1[C][W][OA

    PubMed Central

    Dardelle, Flavien; Lehner, Arnaud; Ramdani, Yasmina; Bardor, Muriel; Lerouge, Patrice; Driouich, Azeddine; Mollet, Jean-Claude

    2010-01-01

    During plant sexual reproduction, pollen germination and tube growth require development under tight spatial and temporal control for the proper delivery of the sperm cells to the ovules. Pollen tubes are fast growing tip-polarized cells able to perceive multiple guiding signals emitted by the female organ. Adhesion of pollen tubes via cell wall molecules may be part of the battery of signals. In order to study these processes, we investigated the cell wall characteristics of in vitro-grown Arabidopsis (Arabidopsis thaliana) pollen tubes using a combination of immunocytochemical and biochemical techniques. Results showed a well-defined localization of cell wall epitopes. Low esterified homogalacturonan epitopes were found mostly in the pollen tube wall back from the tip. Xyloglucan and arabinan from rhamnogalacturonan I epitopes were detected along the entire tube within the two wall layers and the outer wall layer, respectively. In contrast, highly esterified homogalacturonan and arabinogalactan protein epitopes were found associated predominantly with the tip region. Chemical analysis of the pollen tube cell wall revealed an important content of arabinosyl residues (43%) originating mostly from (1→5)-α-l-arabinan, the side chains of rhamnogalacturonan I. Finally, matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of endo-glucanase-sensitive xyloglucan showed mass spectra with two dominant oligosaccharides (XLXG/XXLG and XXFG), both being mono O-acetylated, and accounting for over 68% of the total ion signals. These findings demonstrate that the Arabidopsis pollen tube wall has its own characteristics compared with other cell types in the Arabidopsis sporophyte. These structural features are discussed in terms of pollen tube cell wall biosynthesis and growth dynamics. PMID:20547702

  8. A polysaccharide from pumpkin induces apoptosis of HepG2 cells by activation of mitochondrial pathway.

    PubMed

    Shen, Weixi; Guan, Yuanyuan; Wang, Jingfang; Hu, Yu; Tan, Qian; Song, Xiaowei; Jin, Yinghua; Liu, Ying; Zhang, Yanqiao

    2016-04-01

    Purified white polysaccharide (PPW) is a homogenous polysaccharide isolated from pumpkin, with an average molecular weight of 34 kDa. In this study, we aimed at examining the anti-proliferative activity of PPW against hepatocellular carcinoma (HCC) HepG2 cells and the underlying mechanisms. We found that PPW-induced inhibition of cell proliferation in HepG2 cells was associated with the induction of apoptosis. Exposure of HepG2 cells to PPW (100, 200, and 400 μg/mL) resulted in a loss of mitochondrial membrane potential (Δψm) and the release of cytochrome c from the mitochondria to the cytosol. Also, Western blot analysis revealed dose-dependent increase of pro-apoptotic Bax protein and decrease of anti-apoptotic Bcl-2 protein in PPW-treated cells. Besides, caspase-9 and caspase-3 activities were also enhanced in HepG2 cells followed by PPW treatment. Additionally, the cleavage of poly (ADP-ribose) polymerase (PARP) was observed in PPW-treated HepG2 cells, which altogether account for apoptotic cell death. These results suggested that PPW-induced apoptosis involved a caspase-3-mediated mitochondrial pathway and may have potential as a cancer chemopreventive and therapeutic agent for the prevention and treatment of HCC. PMID:26555544

  9. The Great Pumpkin.

    ERIC Educational Resources Information Center

    Johnson, Maureen; Stone, Judith

    1989-01-01

    Described are five halloween season activities. Included are investigations which focus on observing, measuring, creating, and cooking. A recipe for pumpkin bread is given. Ideas for infusing science into a halloween party are provided. (CW)

  10. Clefting in pumpkin balloons

    NASA Astrophysics Data System (ADS)

    Baginski, F.; Schur, W.

    NASA's effort to develop a large payload, high altitude, long duration balloon, the Ultra Long Duration Balloon, focuses on a pumpkin shape super-pressure design. It has been observed that a pumpkin balloon may be unable to pressurize into the desired cyclically symmetric equilibrium configuration, settling into a distorted, undesired stable state instead. Hoop stress considerations in the pumpkin design leads to choosing the lowest possible bulge radius, while robust deployment is favored by a large bulge radius. Some qualitative understanding of design aspects on undesired equilibria in pumpkin balloons has been obtained via small-scale balloon testing. Poorly deploying balloons have clefts, but most gores away from the cleft deploy uniformly. In this paper, we present models for pumpkin balloons with clefts. Long term success of the pumpkin balloon for NASA requires a thorough understanding of the phenomenon of multiple stable equilibria and means for quantitative assessment of measures that prevent their occurrence. This paper attempts to determine numerical thresholds of design parameters that distinguish between properly deploying designs and improperly deploying designs by analytically investigating designs in the vicinity of criticality. Design elements which may trigger the onset undesired equilibria and remedial measures that ensure deployment are discussed.

  11. Assessment with Pumpkins

    ERIC Educational Resources Information Center

    Sikes, Erin; Sterling, Donna R.

    2006-01-01

    This article describes a pumpkin activity that allows teachers to evaluate their students' understanding of standards-based science skills. This activity is a valuable tool for the teacher to assess all the concepts introduced in the beginning of the life science. It assesses the lab skills that have been taught in the first quarter: observation,…

  12. Effect of Cellulose Synthesis Inhibition on Growth and the Integration of Xyloglucan into Pea Internode Cell Walls 1

    PubMed Central

    Edelmann, Hans G.; Fry, Stephen C.

    1992-01-01

    2,6-Dichlorobenzonitrile (DCB, 100 μm) inhibited by 80 to 85% the incorporation of [3H]glucose into cellulose in stem segments of etiolated pea (Pisum sativum) seedlings. The inhibition lasted for at least 24 h. In the period 1 to 4 h after the excision of the segments, DCB did not influence elongation in the presence or absence of 2,4-dichlorophenoxyacetic acid (2,4-D). However, during the period 1 to 24 h after excision, DCB enhanced endogenous and 2,4-D-stimulated elongation by 65 and 34%, respectively. DCB did not affect the incorporation of 3H from [3H]arabinose into xyloglucan, and did not change the ability of the [3H]xyloglucan formed in vivo to bind strongly to the cell wall. Therefore, at least 80 to 85% of newly synthesized cellulose was excess to the requirements for tight wall binding of newly synthesized xyloglucan. This conflicts with the hypothesis that xyloglucan is held in the cell wall solely by direct hydrogen bonding to the surfaces of cellulosic microfibrils. PMID:16653086

  13. A Mutational Analysis of Killer Toxin Resistance in Saccharomyces Cerevisiae Identifies New Genes Involved in Cell Wall (1 -> 6)-β-Glucan Synthesis

    PubMed Central

    Brown, J. L.; Kossaczka, Z.; Jiang, B.; Bussey, H.

    1993-01-01

    Recessive mutations leading to killer resistance identify the KRE9, KRE10 and KRE11 genes. Mutations in both the KRE9 and KRE11 genes lead to reduced levels of (1 -> 6)-β-glucan in the yeast cell wall. The KRE11 gene encodes a putative 63-kD cytoplasmic protein, and disruption of the KRE11 locus leads to a 50% reduced level of cell wall (1 -> 6)-glucan. Structural analysis of the (1 -> 6)-β-glucan remaining in a kre11 mutant indicates a polymer smaller in size than wild type, but containing a similar proportion of (1 -> 6)- and (1 -> 3)-linkages. Genetic interactions among cells harboring mutations at the KRE11, KRE6 and KRE1 loci indicate lethality of kre11 kre6 double mutants and that kre11 is epistatic to kre1, with both gene products required to produce the mature glucan polymer at wild-type levels. Analysis of these KRE genes should extend knowledge of the β-glucan biosynthetic pathway, and of cell wall synthesis in yeast. PMID:8462845

  14. Mathematics in a Pumpkin Patch.

    ERIC Educational Resources Information Center

    Taffe, William J.

    1978-01-01

    Estimating the weight of large pumpkins before harvest presents an opportunity for applying several diverse mathematical topics. A model that allows an estimation by easy tape measurement is derived. (MP)

  15. Cleft formation in pumpkin balloons

    NASA Astrophysics Data System (ADS)

    Baginski, Frank E.; Brakke, Kenneth A.; Schur, Willi W.

    NASA’s development of a large payload, high altitude, long duration balloon, the Ultra Long Duration Balloon, centers on a pumpkin shape super-pressure design. Under certain circumstances, it has been observed that a pumpkin balloon may be unable to pressurize into the desired cyclically symmetric equilibrium configuration, settling into a distorted, undesired state instead. Success of the pumpkin balloon for NASA requires a thorough understanding of the phenomenon of multiple stable equilibria and developing of means for the quantitative assessment of design measures that prevent the occurrence of undesired equilibrium. In this paper, we will use the concept of stability to classify cyclically symmetric equilibrium states at full inflation and pressurization. Our mathematical model for a strained equilibrium balloon, when applied to a shape that mimics the Phase IV-A balloon of Flight 517, predicts instability at float. Launched in Spring 2003, this pumpkin balloon failed to deploy properly. Observations on pumpkin shape type super-pressure balloons that date back to the 1980s suggest that within a narrowly defined design class of pumpkin shape super-pressure balloons where individual designs are fully described by the number of gores ng and by a single measure of the bulging gore shape, the designs tend to become more vulnerable with the growing number of gores and with the diminishing size of the bulge radius rB Weight efficiency considerations favor a small bulge radius, while robust deployment into the desired cyclically symmetrical configuration becomes more likely with an increased bulge radius. In an effort to quantify this dependency, we will explore the stability of a family of balloon shapes parametrized by (ng, rB) which includes a design that is very similar, but not identical, to the balloon of Flight 517. In addition, we carry out a number of simulations that demonstrate other aspects related to multiple equilibria of pumpkin balloons.

  16. Structure variations of pumpkin balloon

    NASA Astrophysics Data System (ADS)

    Yajima, N.; Izutsu, N.; Honda, H.

    A robed pumpkin balloon by 3-D gore design concept is recognized as a basic form for a super -pressure balloon. This paper deals with an extension of this design concept for other large pressurized membrane structures, such as a stratospheric airship and a balloon of which volume is controllable. The structural modifications are performed by means of additional ropes or poles. When the original pumpkin shape is modified for those systems, superior characteristics of 3-D gore design, those are large bulges with a small local radius and unidirectional film tension, should be maintained. Improved design methods which are adequate for the above subjects will be discussed in detail.

  17. Simulating clefts in pumpkin balloons

    NASA Astrophysics Data System (ADS)

    Baginski, Frank; Brakke, Kenneth

    2010-02-01

    The geometry of a large axisymmetric balloon with positive differential pressure, such as a sphere, leads to very high film stresses. These stresses can be significantly reduced by using a tendon re-enforced lobed pumpkin-like shape. A number of schemes have been proposed to achieve a cyclically symmetric pumpkin shape, including the constant bulge angle (CBA) design, the constant bulge radius (CBR) design, CBA/CBR hybrids, and NASA’s recent constant stress (CS) design. Utilizing a hybrid CBA/CBR pumpkin design, Flight 555-NT in June 2006 formed an S-cleft and was unable to fully deploy. In order to better understand the S-cleft phenomenon, a series of inflation tests involving four 27-m diameter 200-gore pumpkin balloons were conducted in 2007. One of the test vehicles was a 1/3-scale mockup of the Flight 555-NT balloon. Using an inflation procedure intended to mimic ascent, the 1/3-scale mockup developed an S-cleft feature strikingly similar to the one observed in Flight 555-NT. Our analysis of the 1/3-scale mockup found it to be unstable. We compute asymmetric equilibrium configurations of this balloon, including shapes with an S-cleft feature.

  18. Structure variations of pumpkin balloon

    NASA Astrophysics Data System (ADS)

    Yajima, N.; Izutsu, N.; Honda, H.

    2004-01-01

    A lobed pumpkin balloon by 3-D gore design concept is recognized as a basic form for a super-pressure balloon. This paper deals with extensions of this design concept for other large pressurized membrane structures, such as a stratospheric airship and a balloon of which volume is controllable. The structural modifications are performed by means of additional ropes, belts or a strut. When the original pumpkin shape is modified by these systems, the superior characteristics of the 3-D gore design, incorporating large bulges with a small local radius and unidirectional film tension, should be maintained. Improved design methods which are adequate for the above subjects will be discussed in detail. Application for ground structures are also mentioned.

  19. Stability of the pumpkin balloon

    NASA Astrophysics Data System (ADS)

    Baginski, Frank

    A large axisymmetric balloon with positive differential pressure, e.g., a sphere, leads to high film stresses. These can be significantly reduced by using a lobed pumpkin-like shape re-enforced with tendons. A number of schemes have been proposed to achieve a cyclically symmetric pumpkin-shape at full inflation, including the constant bulge angle (CBA) design and the constant bulge radius (CBR) design. The authors and others have carried out stability studies of CBA and CBR designs and found instabilities under various conditions. While stability seems to be a good indicator of deployment problems for large balloons under normal ascent conditions, one cannot conclude that a stable design will deploy reliably. Nevertheless, stability analysis allows one to quantify certain deployment characteristics. Ongoing research by NASA's Balloon Program Office utilizes a new design approach developed by Rodger Farley, NASA/GSFC, that takes into account film and tendon strain. We refer to such a balloon as a constant stress (CS) pumpkin design. In June 2006, the Flight 555-NT balloon (based on a hybrid CBR/CBA design) developed an S-cleft and did not deploy. In order to understand the S-cleft phenomena and study a number of aspects related to the CS-design, a series of inflation tests were conducted at TCOM, Elizabeth City, NC in 2007. The test vehicles were 27 meter diameter pumpkins distinguished by their respective equatorial bulge angles (BA). For example, BA98 indicates an equatorial bulge angle of 98° . BA90, BA55, and BA00 are similarly defined. BA98 was essentially a one-third scale version of of the Flight 555 balloon (i.e., 12 micron film instead of 38.1 micron, mini-tendons, etc.). BA90 and BA55 were Farley CS-designs. BA00 was derived from the BA55 design so that a flat chord spanned adjacent tendons. In this paper, we will carry out stability studies of BA98, BA90, BA55, and BA00. We discuss the deployment problem of pumpkin balloons in light of 2007 inflation

  20. Properties of a small basic Peptide from pumpkin seeds.

    PubMed

    Naisbitt, G H; Lu, M R; Gray, W R; Vernon, L P

    1988-11-01

    A small basic peptide with an unusual amino acid composition has been isolated from the seeds of pumpkin, Cucurbita maxima. Amino acid analysis and sequence data show the protein to be about 36 residues in length, with an approximate composition Lys(1), Arg(14), Asp(3), (Glu + Gln)(15), Gly(1), Pro(1), Trp(1). On the basis of composition, the molecular weight is approximately 5000 daltons and the nitrogen content by weight is 20.4%. Twelve amino acids are entirely lacking. The peptide is slightly toxic to mouse B-16 melanoma cells, but its in vivo function is unknown. It does not appear to be derived from cucurbitin, the pumpkin storage globulin; however, it could be a storage peptide involved in nitrogen mobilization during the early stages of germination. PMID:16666381

  1. Properties of a Small Basic Peptide from Pumpkin Seeds 1

    PubMed Central

    Naisbitt, Gary H.; Lu, Mao-Rong; Gray, William R.; Vernon, Leo P.

    1988-01-01

    A small basic peptide with an unusual amino acid composition has been isolated from the seeds of pumpkin, Cucurbita maxima. Amino acid analysis and sequence data show the protein to be about 36 residues in length, with an approximate composition Lys1, Arg14, Asp3, (Glu + Gln)15, Gly1, Pro1, Trp1. On the basis of composition, the molecular weight is approximately 5000 daltons and the nitrogen content by weight is 20.4%. Twelve amino acids are entirely lacking. The peptide is slightly toxic to mouse B-16 melanoma cells, but its in vivo function is unknown. It does not appear to be derived from cucurbitin, the pumpkin storage globulin; however, it could be a storage peptide involved in nitrogen mobilization during the early stages of germination. Images Fig. 3 PMID:16666381

  2. When Is the World Like a Pumpkin?

    ERIC Educational Resources Information Center

    Rockcastle, Verne N.

    1984-01-01

    Describes a science unit which centers around Halloween festivities and materials. Includes several science activities which use apples and pumpkins to examine such areas as frame of reference and latitude and longitude. (JN)

  3. Deployment Instabilities of Lobed-Pumpkin Balloon

    NASA Astrophysics Data System (ADS)

    Nakashino, Kyoichi

    A lobed-pumpkin balloon, currently being developed in ISAS/JAXA as well as in NASA, is a promising vehicle for long duration scientific observations in the stratosphere. Recent ground and flight experiments, however, have revealed that the balloon has deployment instabilities under certain conditions. In order to overcome the instability problems, a next generation SPB called 'tawara' type balloon has been proposed, in which an additional cylindrical part is appended to the standard lobed-pumpkin balloon. The present study investigates the deployment stability of tawara type SPB in comparison to that of standard lobed-pumpkin SPB through eigenvalue analysis on the basis of finite element methods. Our numerical results show that tawara type SPB enjoys excellent deployment performance over the standard lobed-pumpkin SPBs.

  4. Electrophysiology of pumpkin seeds: Memristors in vivo.

    PubMed

    Volkov, Alexander G; Nyasani, Eunice K; Tuckett, Clayton; Greeman, Esther A; Markin, Vladislav S

    2016-01-01

    Leon Chua, the discoverer of a memristor, theoretically predicted that voltage gated ion channels can be memristors. We recently found memristors in different plants such as the Venus flytrap, Mimosa pudica, Aloe vera, apple fruits, and in potato tubers. There are no publications in literature about the existence of memristors in seeds. The goal of this work was to discover if pumpkin seeds might have memristors. We selected Cucurbita pepo L., cv. Cinderella, Cucurbita maxima L. cv Warty Goblin, and Cucurbita maxima L., cv. Jarrahdale seeds for this analysis. In these seeds, we found the presence of resistors with memory. The analysis was based on cyclic voltammetry where a memristor should manifest itself as a nonlinear two-terminal electrical element, which exhibits a pinched hysteresis loop on a current-voltage plane for any bipolar cyclic voltage input signal. Dry dormant pumpkin seeds have very high electrical resistance without memristive properties. The electrostimulation by bipolar sinusoidal or triangular periodic waves induces electrical responses in imbibed pumpkin seeds with fingerprints of memristors. Tetraethylammonium chloride, an inhibitor of voltage gated K(+) channels, transforms a memristor to a resistor in pumpkin seeds. NPPB (5-Nitro-2-(3-phenylpropylamino)benzoic acid) inhibits the memristive properties of imbibed pumpkin seeds. The discovery of memristors in pumpkin seeds creates a new direction in the understanding of electrophysiological phenomena in seeds. PMID:26926652

  5. Electrophysiology of pumpkin seeds: Memristors in vivo

    PubMed Central

    Volkov, Alexander G.; Nyasani, Eunice K.; Tuckett, Clayton; Greeman, Esther A.; Markin, Vladislav S.

    2016-01-01

    ABSTRACT Leon Chua, the discoverer of a memristor, theoretically predicted that voltage gated ion channels can be memristors. We recently found memristors in different plants such as the Venus flytrap, Mimosa pudica, Aloe vera, apple fruits, and in potato tubers. There are no publications in literature about the existence of memristors in seeds. The goal of this work was to discover if pumpkin seeds might have memristors. We selected Cucurbita pepo L., cv. Cinderella, Cucurbita maxima L. cv Warty Goblin, and Cucurbita maxima L., cv. Jarrahdale seeds for this analysis. In these seeds, we found the presence of resistors with memory. The analysis was based on cyclic voltammetry where a memristor should manifest itself as a nonlinear two-terminal electrical element, which exhibits a pinched hysteresis loop on a current-voltage plane for any bipolar cyclic voltage input signal. Dry dormant pumpkin seeds have very high electrical resistance without memristive properties. The electrostimulation by bipolar sinusoidal or triangular periodic waves induces electrical responses in imbibed pumpkin seeds with fingerprints of memristors. Tetraethylammonium chloride, an inhibitor of voltage gated K+ channels, transforms a memristor to a resistor in pumpkin seeds. NPPB (5-Nitro-2-(3-phenylpropylamino)benzoic acid) inhibits the memristive properties of imbibed pumpkin seeds. The discovery of memristors in pumpkin seeds creates a new direction in the understanding of electrophysiological phenomena in seeds. PMID:26926652

  6. Wide-Angle X-Ray Scattering and Solid-State Nuclear Magnetic Resonance Data Combined to Test Models for Cellulose Microfibrils in Mung Bean Cell Walls1

    PubMed Central

    Newman, Roger H.; Hill, Stefan J.; Harris, Philip J.

    2013-01-01

    A synchrotron wide-angle x-ray scattering study of mung bean (Vigna radiata) primary cell walls was combined with published solid-state nuclear magnetic resonance data to test models for packing of (1→4)-β-glucan chains in cellulose microfibrils. Computer-simulated peak shapes, calculated for 36-chain microfibrils with perfect order or uncorrelated disorder, were sharper than those in the experimental diffractogram. Introducing correlated disorder into the models broaden the simulated peaks but only when the disorder was increased to unrealistic magnitudes. Computer-simulated diffractograms, calculated for 24- and 18-chain models, showed good fits to experimental data. Particularly good fits to both x-ray and nuclear magnetic resonance data were obtained for collections of 18-chain models with mixed cross-sectional shapes and occasional twinning. Synthesis of 18-chain microfibrils is consistent with a model for cellulose-synthesizing complexes in which three cellulose synthase polypeptides form a particle and six particles form a rosette. PMID:24154621

  7. 7. Light tower, interior from entrance, looking northwest Pumpkin ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Light tower, interior from entrance, looking northwest - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  8. 6. Keeper's house, southeast parlor, looking northwest Pumpkin Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Keeper's house, southeast parlor, looking northwest - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  9. Capsicum Annuum L. Lil' Pumpkin and Pepper Jack

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA, ARS announces the release of two new pepper cultivars 05C37-3 (trademarked as Lil’ Pumpkin) and 05C69-12 (trademarked as Pepper Jack). Lil’ Pumpkin and Pepper Jack are intended for ornamental applications. Lil’ Pumpkin’s unique black foliage and orange pumpkin-like fruit and Pepper Jack’s ...

  10. Regulation of Ascorbate Oxidase Expression in Pumpkin by Auxin and Copper 1

    PubMed Central

    Esaka, Muneharu; Fujisawa, Kouichi; Goto, Miwa; Kisu, Yasutomo

    1992-01-01

    Ascorbate oxidase expression in pumpkin (Cucurbita spp.) tissues was studied. Specific ascorbate oxidase activities in pumpkin leaf and stem tissues were about 2 and 1.5 times that in the fruit tissues, respectively. In seeds, little ascorbate oxidase activity was detected. Northern blot analyses showed an abundant ascorbate oxidase mRNA in leaf and stem tissues. Fruit tissues had lower levels of ascorbate oxidase mRNA than leaf and stem tissues. Ascorbate oxidase mRNA was not detected in seeds. Specific ascorbate oxidase activity gradually increased during early seedling growth of pumpkin seeds. The increase was accompanied by an increase in ascorbate oxidase mRNA. When ascorbate oxidase activity in developing pumpkin fruits was investigated, the activities in immature fruits that are rapidly growing at 0, 2, 4, and 7 d after anthesis were much higher than those in mature fruits at 14 and 30 d after anthesis. The specific activity and mRNA of ascorbate oxidase markedly increased after inoculation of pumpkin fruit tissues into Murashige and Skoog's culture medium in the presence of an auxin such as 2,4-dichlorophenoxyacetic acid (2,4-D) but not in the absence of 2,4-D. In the presence of 10 mg/L of 2,4-D, ascorbate oxidase mRNA was the most abundant. Thus, ascorbate oxidase is induced by 2,4-D. These results indicate that ascorbate oxidase is involved in cell growth. In pumpkin callus, ascorbate oxidase activity could be markedly increased by adding copper. Furthermore, immunological blotting showed that the amount of ascorbate oxidase protein was also increased by adding copper. However, northern blot analyses showed that ascorbate oxidase mRNA was not increased by adding copper. We suggest that copper may control ascorbate oxidase expression at translation or at a site after translation. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:16652952

  11. Regulation of ascorbate oxidase expression in pumpkin by auxin and copper.

    PubMed

    Esaka, M; Fujisawa, K; Goto, M; Kisu, Y

    1992-09-01

    Ascorbate oxidase expression in pumpkin (Cucurbita spp.) tissues was studied. Specific ascorbate oxidase activities in pumpkin leaf and stem tissues were about 2 and 1.5 times that in the fruit tissues, respectively. In seeds, little ascorbate oxidase activity was detected. Northern blot analyses showed an abundant ascorbate oxidase mRNA in leaf and stem tissues. Fruit tissues had lower levels of ascorbate oxidase mRNA than leaf and stem tissues. Ascorbate oxidase mRNA was not detected in seeds. Specific ascorbate oxidase activity gradually increased during early seedling growth of pumpkin seeds. The increase was accompanied by an increase in ascorbate oxidase mRNA. When ascorbate oxidase activity in developing pumpkin fruits was investigated, the activities in immature fruits that are rapidly growing at 0, 2, 4, and 7 d after anthesis were much higher than those in mature fruits at 14 and 30 d after anthesis. The specific activity and mRNA of ascorbate oxidase markedly increased after inoculation of pumpkin fruit tissues into Murashige and Skoog's culture medium in the presence of an auxin such as 2,4-dichlorophenoxyacetic acid (2,4-D) but not in the absence of 2,4-D. In the presence of 10 mg/L of 2,4-D, ascorbate oxidase mRNA was the most abundant. Thus, ascorbate oxidase is induced by 2,4-D. These results indicate that ascorbate oxidase is involved in cell growth. In pumpkin callus, ascorbate oxidase activity could be markedly increased by adding copper. Furthermore, immunological blotting showed that the amount of ascorbate oxidase protein was also increased by adding copper. However, northern blot analyses showed that ascorbate oxidase mRNA was not increased by adding copper. We suggest that copper may control ascorbate oxidase expression at translation or at a site after translation. PMID:16652952

  12. Viscoelastic behaviour of pumpkin balloons

    NASA Astrophysics Data System (ADS)

    Gerngross, T.; Xu, Y.; Pellegrino, S.

    2008-11-01

    The lobes of the NASA ULDB pumpkin-shaped super-pressure balloons are made of a thin polymeric film that shows considerable time-dependent behaviour. A nonlinear viscoelastic model based on experimental measurements has been recently established for this film. This paper presents a simulation of the viscoelastic behaviour of ULDB balloons with the finite element software ABAQUS. First, the standard viscoelastic modelling capabilities available in ABAQUS are examined, but are found of limited accuracy even for the case of simple uniaxial creep tests on ULDB films. Then, a nonlinear viscoelastic constitutive model is implemented by means of a user-defined subroutine. This approach is verified by means of biaxial creep experiments on pressurized cylinders and is found to be accurate provided that the film anisotropy is also included in the model. A preliminary set of predictions for a single lobe of a ULDB is presented at the end of the paper. It indicates that time-dependent effects in a balloon structure can lead to significant stress redistribution and large increases in the transverse strains in the lobes.

  13. Ultrasound Assisted Extraction of Phenolic Compounds from Peaches and Pumpkins.

    PubMed

    Altemimi, Ammar; Watson, Dennis G; Choudhary, Ruplal; Dasari, Mallika R; Lightfoot, David A

    2016-01-01

    The ultrasound-assisted extraction (UAE) method was used to optimize the extraction of phenolic compounds from pumpkins and peaches. The response surface methodology (RSM) was used to study the effects of three independent variables each with three treatments. They included extraction temperatures (30, 40 and 50°C), ultrasonic power levels (30, 50 and 70%) and extraction times (10, 20 and 30 min). The optimal conditions for extractions of total phenolics from pumpkins were inferred to be a temperature of 41.45°C, a power of 44.60% and a time of 25.67 min. However, an extraction temperature of 40.99°C, power of 56.01% and time of 25.71 min was optimal for recovery of free radical scavenging activity (measured by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) reduction). The optimal conditions for peach extracts were an extraction temperature of 41.53°C, power of 43.99% and time of 27.86 min for total phenolics. However, an extraction temperature of 41.60°C, power of 44.88% and time of 27.49 min was optimal for free radical scavenging activity (judged by from DPPH reduction). Further, the UAE processes were significantly better than solvent extractions without ultrasound. By electron microscopy it was concluded that ultrasonic processing caused damage in cells for all treated samples (pumpkin, peach). However, the FTIR spectra did not show any significant changes in chemical structures caused by either ultrasonic processing or solvent extraction. PMID:26885655

  14. Ultrasound Assisted Extraction of Phenolic Compounds from Peaches and Pumpkins

    PubMed Central

    Altemimi, Ammar; Watson, Dennis G.; Choudhary, Ruplal; Dasari, Mallika R.; Lightfoot, David A.

    2016-01-01

    The ultrasound-assisted extraction (UAE) method was used to optimize the extraction of phenolic compounds from pumpkins and peaches. The response surface methodology (RSM) was used to study the effects of three independent variables each with three treatments. They included extraction temperatures (30, 40 and 50°C), ultrasonic power levels (30, 50 and 70%) and extraction times (10, 20 and 30 min). The optimal conditions for extractions of total phenolics from pumpkins were inferred to be a temperature of 41.45°C, a power of 44.60% and a time of 25.67 min. However, an extraction temperature of 40.99°C, power of 56.01% and time of 25.71 min was optimal for recovery of free radical scavenging activity (measured by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) reduction). The optimal conditions for peach extracts were an extraction temperature of 41.53°C, power of 43.99% and time of 27.86 min for total phenolics. However, an extraction temperature of 41.60°C, power of 44.88% and time of 27.49 min was optimal for free radical scavenging activity (judged by from DPPH reduction). Further, the UAE processes were significantly better than solvent extractions without ultrasound. By electron microscopy it was concluded that ultrasonic processing caused damage in cells for all treated samples (pumpkin, peach). However, the FTIR spectra did not show any significant changes in chemical structures caused by either ultrasonic processing or solvent extraction. PMID:26885655

  15. Soil, Seeds, and the Pumpkin Patch!

    ERIC Educational Resources Information Center

    Phillips, Marianne; Vowell, Julie

    2013-01-01

    "Soil, Seeds, and the Pumpkin Patch!" is an integrated unit designed to provide elementary school teachers with ideas for using hands-on activities, fostering inquiry and valuable discussion, and using technology as a learning tool. This unit integrates science with language arts, mathematics, literature, and technology. During this unit, students…

  16. Over-expression of specific HvCslF cellulose synthase-like genes in transgenic barley increases the levels of cell wall (1,3;1,4)-β-d-glucans and alters their fine structure.

    PubMed

    Burton, Rachel A; Collins, Helen M; Kibble, Natalie A J; Smith, Jessica A; Shirley, Neil J; Jobling, Stephen A; Henderson, Marilyn; Singh, Rohan R; Pettolino, Filomena; Wilson, Sarah M; Bird, Anthony R; Topping, David L; Bacic, Antony; Fincher, Geoffrey B

    2011-02-01

    Cell walls in commercially important cereals and grasses are characterized by the presence of (1,3;1,4)-β-d-glucans. These polysaccharides are beneficial constituents of human diets, where they can reduce the risk of hypercholesterolemia, type II diabetes, obesity and colorectal cancer. The biosynthesis of cell wall (1,3;1,4)-β-d-glucans in the Poaceae is mediated, in part at least, by the cellulose synthase-like CslF family of genes. Over-expression of the barley CslF6 gene under the control of an endosperm-specific oat globulin promoter results in increases of more than 80% in (1,3;1,4)-β-d-glucan content in grain of transgenic barley. Analyses of (1,3;1,4)-β-d-glucan fine structure indicate that individual CslF enzymes might direct the synthesis of (1,3;1,4)-β-d-glucans with different structures. When expression of the CslF6 transgene is driven by the Pro35S promoter, the transgenic lines have up to sixfold higher levels of (1,3;1,4)-β-d-glucan in leaves, but similar levels as controls in the grain. Some transgenic lines of Pro35S:CslF4 also show increased levels of (1,3;1,4)-β-d-glucans in grain, but not in leaves. Thus, the effects of CslF genes on (1,3;1,4)-β-d-glucan levels are dependent not only on the promoter used, but also on the specific member of the CslF gene family that is inserted into the transgenic barley lines. Altering (1,3;1,4)-β-d-glucan levels in grain and vegetative tissues will have potential applications in human health, where (1,3;1,4)-β-d-glucans contribute to dietary fibre, and in tailoring the composition of biomass cell walls for the production of bioethanol from cereal crop residues and grasses. PMID:20497371

  17. Structural characteristics of pumpkin pectin extracted by microwave heating

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To improve extraction yield of pumpkin pectin, microwave heating was adopted in this study. Using traditional hot acid extraction, pumpkin pectin yield decreased from 5.7 to 1.0 % as pH increased from pH 1.0 to 2.0. At pH 2.5, no pectin was recovered from pumpkin flesh powder. After a pre-treatment ...

  18. Blanching, salting and sun drying of different pumpkin fruit slices.

    PubMed

    Workneh, T S; Zinash, A; Woldetsadik, K

    2014-11-01

    The study was aimed at assessing the quality of pumpkin (Cucuribita Spp.) slices that were subjected to pre-drying treatments and drying using two drying methods (uncontrolled sun and oven) fruit accessions. Pre-drying had significant (P ≤ 0.05) effect on the quality of dried pumpkin slices. 10 % salt solution dipped pumpkin fruit slices had good chemical quality. The two-way interaction between drying methods and pre-drying treatments had significant (P ≤ 0.05) effect on chemical qualities. Pumpkin subjected to salt solution dipping treatment and oven dried had higher chemical concentrations. Among the pumpkin fruit accessions, pumpkin accession 8007 had the superior TSS, total sugar and sugar to acid ratio after drying. Among the three pre-drying treatment, salt solution dipping treatment had significant (P ≤ 0.05) effect and the most efficient pre-drying treatment to retain the quality of dried pumpkin fruits without significant chemical quality deterioration. Salt dipping treatment combined with low temperature (60 °C) oven air circulation drying is recommended to maintain quality of dried pumpkin slices. However, since direct sun drying needs extended drying time due to fluctuation in temperature, it is recommended to develop or select best successful solar dryer for use in combination with pre-drying salt dipping or blanching treatments. PMID:26396303

  19. Genetic Transformation of Watermelon with Pumpkin DNA by Low Energy Ion Beam-Mediated Introduction

    NASA Astrophysics Data System (ADS)

    Wang, Hao-bo; Gao, Xiu-wu; Guo, Jin-hua; Huang, Qun-ce; Yu, Zeng-liang

    2002-12-01

    The No.601 watermelon (citrullus lanatus) seeds were treated with 25 keV N+ implantation at the dosage of 7.8 × 1016 ions/cm2. After treatment, watermelon seeds were incubated with 380 μg/μl pumpkin (Cucubita, maxima Duch) DNA solution at 35 °C for 5 hours. By two-generations of selection and resistance screening at seedling stage, one transformed material was selected out, whose rind color is similar to that of the donor pumpkin and whose size of seeds is between that of the donor and the receptor. Using AFLP (amplified fragment length polymorphism) technique, two polymorphic DNA fragments were amplified. This primarily testified that the donor DNA fragments/gene were introduced into the receptor cell and integrated into the genomic DNA of the receptor.

  20. Meshed-Pumpkin Super-Pressure Balloon Design

    NASA Technical Reports Server (NTRS)

    Jones, Jack; Yavrouian, Andre

    2003-01-01

    An improved, lightweight design has been proposed for super-pressure balloons used to carry scientific instruments at high altitudes in the atmosphere of Earth for times as long as 100 days. [A super-pressure balloon is one in which the pressure of the buoyant gas (typically, helium) is kept somewhat above ambient pressure in order to maintain approximately constant density and thereby regulate the altitude.] The proposed design, called "meshed pumpkin," incorporates the basic concept of the pumpkin design, which is so named because of its appearance. The pumpkin design entails less weight than does a spherical design, and the meshed-pumpkin design would reduce weight further. The basic idea of the meshed-pumpkin design is to reinforce the membrane of a pumpkin balloon by attaching a strong, lightweight fabric mesh to its outer surface. The reinforcement would make it possible to reduce the membrane mass to one-third or less of that of the basic pumpkin design while retaining sufficient strength to enable the balloon to remain at approximately constant altitude for months.

  1. Evaluating pollination deficits in pumpkin production in New York.

    PubMed

    Petersen, J D; Huseth, A S; Nault, B A

    2014-10-01

    Potential decreases in crop yield from reductions in bee-mediated pollination services threaten food production demands of a growing population. Many fruit and vegetable growers supplement their fields with bee colonies during crop bloom. The extent to which crop production requires supplementary pollination services beyond those provided by wild bees is not well documented. Pumpkin, Cucurbita pepo L., requires bee-mediated pollination for fruit development. Previous research identified the common eastern bumble bee, Bombus impatiens (Cresson), as the most efficient pumpkin pollinator. Two concomitant studies were conducted to examine pollination deficits in New York pumpkin fields from 2011 to 2013. In the first study, fruit weight, seed set, and B. impatiens visits to pumpkin flowers were compared across fields supplemented with B. impatiens colonies at a recommended stocking density of five colonies per hectare, a high density of 15 colonies per hectare, or not supplemented with bees. In the second study, fruit weight and seed set of pumpkins that received supplemental pollen through hand-pollination were compared with those that were open-pollinated by wild bees. Results indicated that supplementing pumpkin fields with B. impatiens colonies, regardless of stocking density, did not increase fruit weight, seed set, or B. impatiens visits to pumpkin flowers. Fruit weight and seed set did not differ between hand- and open-pollinated treatments. In general, we conclude that pumpkin production in central New York is not limited by inadequate pollination services provided by wild bees and that on average, supplementation with B. impatiens colonies did not improve pumpkin yield. PMID:25198126

  2. Numerical Modelling Of Pumpkin Balloon Instability

    NASA Astrophysics Data System (ADS)

    Wakefield, D.

    Tensys have been involved in the numerical formfinding and load analysis of architectural stressed membrane structures for 15 years. They have recently broadened this range of activities into the `lighter than air' field with significant involvement in aerostat and heavy-lift hybrid airship design. Since early 2004 they have been investigating pumpkin balloon instability on behalf of the NASA ULDB programme. These studies are undertaken using inTENS, an in-house finite element program suite based upon the Dynamic Relaxation solution method and developed especially for the non-linear analysis and patterning of membrane structures. The paper describes the current state of an investigation that started with a numerical simulation of the lobed cylinder problem first studied by Calladine. The influence of material properties and local geometric deformation on stability is demonstrated. A number of models of complete pumpkin balloons have then been established, including a 64-gore balloon with geometry based upon Julian Nott's Endeavour. This latter clefted dramatically upon initial inflation, a phenomenon that has been reproduced in the numerical model. Ongoing investigations include the introduction of membrane contact modelling into inTENS and correlation studies with the series of large-scale ULDB models currently in preparation.

  3. Combined infrared-vacuum drying of pumpkin slices.

    PubMed

    Ghaboos, Seyyed Hossein Hosseini; Ardabili, Seyed Mahdi Seyedain; Kashaninejad, Mahdi; Asadi, Gholamhassan; Aalami, Mehran

    2016-05-01

    Infrared-vacuum dehydration characteristics of pumpkin (Cucurbita moschata) were evaluated in a combined dryer system. The effects of drying parameters, infrared radiation power (204-272 W), system pressure (5-15 kPa), slice thickness (5 and 7 mm) and time (0-220 min) on the drying kinetics and characteristics of pumpkin slices were investigated. The vacuum pressure, lamp power and slice had significant effect on the drying kinetics and various qualities of the dried pumpkin. Moisture ratios were fitted to 10 different mathematical equations using nonlinear regression analysis. The quadratic equation satisfactorily described the drying behavior of pumpkin slices with the highest r value and the lowest SE values. The effective moisture diffusivity increased with power and ranged between 0.71 and 2.86 × 10(-9) m(2)/s. With increasing in infrared radiation power from 204 to 272 W, β-carotene content of dried pumpkins decreased from 30.04 to 24.55 mg/100 g. The rise in infrared power has a negative effect on the color changes (ΔE). The optimum condition was determined as power, 238W, pressure, 5 kPa and slice thickness, 5mm. These conditions resulted into dried pumpkin slices with maximum B-carotene retention. PMID:27407204

  4. Crystallization of pumpkin seed globulin: growth and dissolution kinetics

    NASA Astrophysics Data System (ADS)

    Malkin, Alexander J.; McPherson, Alexander

    1993-10-01

    Quasi-elastic light scattering was used to investigate the nucleation and crystallization of pumpkin ( Cucurbita) seed globulin. The diameter of the pumpkin globulin monomer was measured to be ≈ 5-6 nm. The supersaturation dependence of critical nucleus size was obtained, and this allowed an estimate of the interfacial free energy to be α ≈ 6.1 x 10 -2 erg/cm 2. The crystallization and dissolution kinetics were investigated for 4.9-16 mg/ml protein solutions containing 1-7% NaCl. The solubility data as a function of precipitant concentration and temperature were obtained and these will be utilized for optimization of the crystallization conditions for the pumpkin globulin.

  5. Pumpkins and onions and balloon design

    NASA Astrophysics Data System (ADS)

    Winker, J. A.

    The reach for a capability to make long flights (months) with heavy payloads (tonnes) has long been pursued. The closest we have come is with polar flights devoid of a significant diurnal cycle. Superpressure technology, with its ability to survive diurnal cycles, is an obvious choice, but materials limitations have been an obstacle to realizing these ambitious goals. Now comes an assortment of new synthetic materials, coupled with a special variety of superpressure balloon which, in combination, is poised to yield a solution for our enhanced duration/payload quest. In this paper we are looking not at materials, but only at a balloon concept. This concept is a "natural shape" oblate spheroid balloon whose shape is chosen to exploit properties of component materials, particularly newly available ones. The current variation of this concept is called a "pumpkin" balloon. The most visible work on this shape is that done by France's CNES, Japan's ISAS, and in the USA by NASA's Wallops Flight Facility. But the basic design idea is not new; it extends back at least a half century. This paper traces the origins of the shape, its evolution through various iterations, and it speculates on some of the recent thinking regarding construction details.

  6. Antihypertensive and cardioprotective effects of pumpkin seed oil.

    PubMed

    El-Mosallamy, Aliaa E M K; Sleem, Amany A; Abdel-Salam, Omar M E; Shaffie, Nermeen; Kenawy, Sanaa A

    2012-02-01

    Pumpkin seed oil is a natural product commonly used in folk medicine for treatment of prostatic hypertrophy. In the present study, the effects of treatment with pumpkin seed oil on hypertension induced by the nitric oxide synthase inhibitor N(ω)-nitro-L-arginine methyl ester hydrochloride (L-NAME) (50 mg /kg/day) in rats were studied and compared with those of the calcium channel blocker amlodipine. Pumpkin seed oil (40 or 100 mg/kg), amlodipine (0.9 mg/kg), or vehicle (control) was given once daily orally for 6 weeks. Arterial blood pressure (BP), heart rate, electrocardiogram (ECG) changes, levels of serum nitric oxide (NO) (the concentrations of nitrite/nitrate), plasma malondialdehyde (MDA), blood glutathione, and erythrocytic superoxide dismutase activity were measured. Histopathological examination of heart and aorta was conducted as well. L-NAME administration resulted in a significant increase in BP starting from the second week. Pumpkin seed oil or amlodipine treatment significantly reduced the elevation in BP by L-NAME and normalized the L-NAME-induced ECG changes-namely, prolongation of the RR interval, increased P wave duration, and ST elevation. Both treatments significantly decreased the elevated levels of MDA and reversed the decreased levels of NO metabolites to near normal values compared with the L-NAME-treated group. Amlodipine also significantly increased blood glutathione content compared with normal (but not L-NAME-treated) rats. Pumpkin seed oil as well as amlodipine treatment protected against pathological alterations in heart and aorta induced by L-NAME. In conclusion, this study has shown that pumpkin seed oil exhibits an antihypertensive and cardioprotective effects through a mechanism that may involve generation of NO. PMID:22082068

  7. De novo transcriptome assembly of two contrasting pumpkin cultivars.

    PubMed

    Xanthopoulou, Aliki; Psomopoulos, Fotis; Ganopoulos, Ioannis; Manioudaki, Maria; Tsaftaris, Athanasios; Nianiou-Obeidat, Irini; Madesis, Panagiotis

    2016-03-01

    Cucurbita pepo (squash, pumpkin, gourd), a worldwide-cultivated vegetable of American origin, is extremely variable in fruit characteristics. However, the information associated with genes and genetic markers for pumpkin is very limited. In order to identify new genes and to develop genetic markers, we performed a transcriptome analysis (RNA-Seq) of two contrasting pumpkin cultivars. Leaves and female flowers of cultivars, 'Big Moose' with large round fruits and 'Munchkin' with small round fruits, were harvested for total RNA extraction. We obtained a total of 6 GB (Big Moose; http://www.ncbi.nlm.nih.gov/Traces/sra/?run=SRR3056882) and 5 GB (Munchkin; http://www.ncbi.nlm.nih.gov/Traces/sra/?run=SRR3056883) sequence data (NCBI SRA database SRX1502732 and SRX1502735, respectively), which correspond to 18,055,786 and 14,824,292 150-base reads. After quality assessment, the clean sequences where 17,995,932 and 14,774,486 respectively. The numbers of total transcripts for 'Big Moose' and 'Munchkin' were 84,727 and 68,051, respectively. TransDecoder identified possible coding regions in assembled transcripts. This study provides transcriptome data for two contrasting pumpkin cultivars, which might be useful for genetic marker development and comparative transcriptome analyses. PMID:26981408

  8. De novo transcriptome assembly of two contrasting pumpkin cultivars

    PubMed Central

    Xanthopoulou, Aliki; Psomopoulos, Fotis; Ganopoulos, Ioannis; Manioudaki, Maria; Tsaftaris, Athanasios; Nianiou-Obeidat, Irini; Madesis, Panagiotis

    2016-01-01

    Cucurbita pepo (squash, pumpkin, gourd), a worldwide-cultivated vegetable of American origin, is extremely variable in fruit characteristics. However, the information associated with genes and genetic markers for pumpkin is very limited. In order to identify new genes and to develop genetic markers, we performed a transcriptome analysis (RNA-Seq) of two contrasting pumpkin cultivars. Leaves and female flowers of cultivars, ‘Big Moose’ with large round fruits and ‘Munchkin’ with small round fruits, were harvested for total RNA extraction. We obtained a total of 6 GB (Big Moose; http://www.ncbi.nlm.nih.gov/Traces/sra/?run=SRR3056882) and 5 GB (Munchkin; http://www.ncbi.nlm.nih.gov/Traces/sra/?run=SRR3056883) sequence data (NCBI SRA database SRX1502732 and SRX1502735, respectively), which correspond to 18,055,786 and 14,824,292 150-base reads. After quality assessment, the clean sequences where 17,995,932 and 14,774,486 respectively. The numbers of total transcripts for ‘Big Moose’ and ‘Munchkin’ were 84,727 and 68,051, respectively. TransDecoder identified possible coding regions in assembled transcripts. This study provides transcriptome data for two contrasting pumpkin cultivars, which might be useful for genetic marker development and comparative transcriptome analyses. PMID:26981408

  9. FATTY ACID COMPOSITION AND TOCOPHEROL CONTENT OF PUMPKIN SEED OIL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pumpkin seed oil (PSO) has high tocopherol content (TC) and unsaturated fatty acids (UFA) making it well-suited for improving human nutrition. PSO has been implicated in preventing prostate growth, retarding hypertension, mitigating hypercholesterolemia and arthritis, improved bladder compliance, a...

  10. Analyzing atmospheric kinetic pathways using PumpKin

    NASA Astrophysics Data System (ADS)

    Markosyan, A. H.; Luque, A.; Gordillo-Vázquez, F. J.; Ebert, U.

    2013-09-01

    In the present work we show the application of our software tool called PumpKin (pathway reduction method for plasma kinetic models) to find all principal pathways of atmospheric kinetic system, i.e. the dominant reaction sequences, in chemical reaction systems. The goal was to reduce a complex plasma chemistry model. Recent kinetic models of atmospheric chemistry, or any industrial application, contain thousands of chemical reactions and species. The main difficulty is that these reduced chemical pathways depend on timescales, electric field, temperature, pressure etc. PumpKin is a universal tool, which only requires from user the temporal profile of the densities of species and the reaction rates, as well the stoichiometric matrix of the system. Also, the user should specify the timescale of interest.

  11. Proglobulin processing enzyme in vacuoles isolated from developing pumpkin cotyledons

    SciTech Connect

    Hara-Nishimura, I.; Nishimura, M.

    1987-10-01

    The enzymic conversion of proglobulin to globulin catalyzed by the extracts of vacuoles isolated from developing pumpkin (Cucurbita sp. cv Kurokawa Amakuri Nankin) cotyledons was investigated. The endoplasmic reticulum fraction isolated from the developing cotyledons pulse-labeled with (/sup 35/S)methionine was shown to contain mainly the radiolabeled proglobulin, which was used as a substrate for assaying the proteolytic processing in vitro. The vacuolar extracts catalyzed the proteolytic processing of the proglobulin molecule to produce globulin containing two kinds of polypeptide chains, ..gamma.. and delta. The pH optimum for the vacuole-mediated conversion was at pH 5.0. The proteolytic processing of proglobulin by the vacuolar extracts was inhibited in the presence of various thiol reagents, e.g. p-chloromercuribenzoate, N-ethylmaleimide, iodoacetic acid, Hg/sup 2 +/, and Cu/sup 2 +/, but not phenylmethylsulfonyl fluoride, EDTA, o-phenanthroline, leupeptin, antipain, pepstatin, chymostatin, or pumpkin trypsin inhibitor, and was activated in the presence of dithiothreitol and cysteine, indicating that the processing enzyme is a thiol protease. The suborganellar fractionation of the vacuoles showed that the processing activity was localized in the matrix fraction, but not in the membrane or crystalloid fractions. During the seed development, the enzyme was shown to increase, exhibiting the maximal activity at the late developmental stage. The matrix fraction of the protein bodies isolated from the dry castor bean (Ricinus communis) exhibited the processing activity toward the pumpkin proglobulin molecules in the same manner as that by the matrix fraction of pumpkin vacuoles.

  12. Physicochemical and functional properties of peeled and unpeeled pumpkin flour.

    PubMed

    Noor Aziah, A A; Komathi, C A

    2009-09-01

    This study was intended to investigate the potential of peeled and unpeeled pumpkin pulp as a raw material for the production of flour that could be used in composite blend with wheat flour or as a functional ingredient in food products. The peeled and unpeeled pumpkin pulp were soaked in sodium metabisulphite solution, sliced and dried overnight in a hot air oven, followed by milling into peeled pumpkin pulp flour (PPPF) and unpeeled pumpkin pulp flour (UPPF), respectively. The flours were then evaluated for physicochemical attributes (color, proximate compositions, and water activity) and functional properties (water holding capacity and oil holding capacity), in comparison to the commercial wheat flour. PPPF and UPPF were observed to be more attractive in terms of color than wheat flour, as indicated by the significantly higher results (P or= 0.05) was shown in water holding capacity of PPPF and wheat flour. However, the oil holding capacity of PPPF and UPPF was shown to be significantly higher (P

  13. Pumpkin-Derived Porous Carbon for Supercapacitors with High Performance.

    PubMed

    Bai, Suying; Tan, Guangqun; Li, Xiaoqin; Zhao, Qian; Meng, Yan; Wang, Yujue; Zhang, Yongzhi; Xiao, Dan

    2016-06-21

    Pumpkin has been employed for the first time as a renewable, low-cost precursor for the preparation of porous carbon materials with excellent performance. Unlike most other precursors, pumpkin is rich in sugars and starch, and it has advantageous properties for large-scale production. The as-prepared materials adopted a unique morphology that consisted of numerous fused sphere-like carbon grains with a high specific surface area (2968 m(2)  g(-1) ), abundant micro and mesopores, and excellent electrochemical properties. The pumpkin-derived activated carbon (PAC) material not only exhibited a high specific capacitance of 419 F g(-1) , but also showed considerable cycling stability, with 93.6 % retention after 10 000 cycles. Moreover, a symmetrical supercapacitor that was based on PAC showed a high energy density of 22.1 W h kg(-1) in aqueous electrolyte. These superior properties demonstrate that PAC holds great promise for applications in electrochemical energy-storage devices. PMID:27124360

  14. Time-dependent strains and stresses in a pumpkin balloon

    NASA Astrophysics Data System (ADS)

    Gerngross, T.; Xu, Y.; Pellegrino, S.

    This paper presents a study of pumpkin-shaped superpressure balloons consisting of gores made from a thin polymeric film attached to high stiffness meridional tendons This type of design is being used for the NASA ULDB balloons The gore film shows considerable time-dependent stress relaxation whereas the behaviour of the tendons is essentially time-independent Upon inflation and pressurization the instantaneous i e linear-elastic strain and stress distributions in the film show significantly higher values in the meridional direction However over time and due to the biaxial visco-elastic stress relaxation of the the gore material the em hoop strains increase and the em meridional stresses decrease whereas the em remaining strain and stress components remain substantially unchanged These results are important for a correct assessment of the structural integrity of a pumpkin balloon in a long-duration mission both in terms of the material performance and the overall stability of the shape of the balloon An experimental investigation of the time dependence of the biaxial strain distribution in the film of a 4 m diameter 48 gore pumpkin balloon is presented The inflated shape of selected gores has been measured using photogrammetry and the time variation in strain components at some particular points of these gores has been measured under constant pressure and temperature The results show good correlation with a numerical study using the ABAQUS finite-element package that includes a widely used model of

  15. Time-dependent strains and stresses in a pumpkin balloon

    NASA Technical Reports Server (NTRS)

    Gerngross, T.; Xu, Y.; Pellegrino, S.

    2006-01-01

    This paper presents a study of pumpkin-shaped superpressure balloons, consisting of gores made from a thin polymeric film attached to high stiffness, meridional tendons. This type of design is being used for the NASA ULDB balloons. The gore film shows considerable time-dependent stress relaxation, whereas the behaviour of the tendons is essentially time-independent. Upon inflation and pressurization, the "instantaneous", i.e. linear-elastic strain and stress distribution in the film show significantly higher values in the meridional direction. However, over time, and due to the biaxial visco-elastic stress relaxation of the the material, the hoop strains increase and the meridional stresses decrease, whereas the remaining strain and stress components remain substantially unchanged. These results are important for a correct assessment of the structural integrity of a pumpkin balloon in a long-duration mission, both in terms of the material performance and the overall stability of the shape of the balloon. An experimental investigation of the time dependence of the biaxial strain distribution in the film of a 4 m diameter, 48 gore pumpkin balloon is presented. The inflated shape of selected gores has been measured using photogrammetry and the time variation in strain components at some particular points of these gores has been measured under constant pressure and temperature. The results show good correlation with a numerical study, using the ABAQUS finite-element package, that includes a widely used model of the visco-elastic response of the gore material:

  16. Farming practices influence wild pollinator populations on squash and pumpkin.

    PubMed

    Shuler, Rachel E; Roulston, Tai H; Farris, Grace E

    2005-06-01

    Recent declines in managed honey bee, Apis mellifera L., colonies have increased interest in the current and potential contribution of wild bee populations to the pollination of agricultural crops. Because wild bees often live in agricultural fields, their population density and contribution to crop pollination may be influenced by farming practices, especially those used to reduce the populations of other insects. We took a census of pollinators of squash and pumpkin at 25 farms in Virginia, West Virginia, and Maryland to see whether pollinator abundance was related to farming practices. The main pollinators were Peponapis pruinosa Say; honey bees, and bumble bees (Bombus spp.). The squash bee was the most abundant pollinator on squash and pumpkin, occurring at 23 of 25 farms in population densities that were commonly several times higher than that of other pollinators. Squash bee density was related to tillage practices: no-tillage farms hosted three times as great a density of squash bees as tilled farms. Pollinator density was not related to pesticide use. Honey bee density on squash and pumpkin was not related to the presence of managed honey bee colonies on farms. Farms with colonies did not have more honey bees per flower than farms that did not keep honey bees, probably reflecting the lack of affinity of honey bees for these crops. Future research should examine the economic impacts of managing farms in ways that promote pollinators, particularly pollinators of crops that are not well served by managed honey bee colonies. PMID:16022307

  17. Experimental investigation of undesired stable equilibria in pumpkin shape super-pressure balloon designs

    NASA Astrophysics Data System (ADS)

    Schur, W. W.

    2004-01-01

    Excess in skin material of a pneumatic envelope beyond what is required for minimum enclosure of a gas bubble is a necessary but by no means sufficient condition for the existence of multiple equilibrium configurations for that pneumatic envelope. The very design of structurally efficient super-pressure balloons of the pumpkin shape type requires such excess. Undesired stable equilibria in pumpkin shape balloons have been observed on experimental pumpkin shape balloons. These configurations contain regions with stress levels far higher than those predicted for the cyclically symmetric design configuration under maximum pressurization. Successful designs of pumpkin shape super-pressure balloons do not allow such undesired stable equilibria under full pressurization. This work documents efforts made so far and describes efforts still underway by the National Aeronautics and Space Administration's Balloon Program Office to arrive on guidance on the design of pumpkin shape super-pressure balloons that guarantee full and proper deployment.

  18. Pumpkin Seed Oil Extracted From Cucurbita maxima Improves Urinary Disorder in Human Overactive Bladder.

    PubMed

    Nishimura, Mie; Ohkawara, Tatsuya; Sato, Hiroji; Takeda, Hiroshi; Nishihira, Jun

    2014-01-01

    The pumpkin seed oil obtained from Cucurbita pepo has been shown to be useful for the treatment of nocturia in patients with urinal disorders in several western countries. In this study, we evaluated the effect of the pumpkin seed oil from Cucurbita maxima on urinary dysfunction in human overactive bladder (OAB). Forty-five subjects were enrolled in this study. An extract of pumpkin seed oil from C. maxima (10 g of oil/day) was orally administrated for 12 weeks. After 6 and 12 weeks, urinary function was evaluated using Overactive Bladder Symptom Score (OABSS). Pumpkin seed oil from C. maxima significantly reduced the degree of OABSS in the subjects. The results from our study suggest that pumpkin seed oil extracts from C. maxima as well as from C. pepo are effective for urinary disorders such as OAB in humans. PMID:24872936

  19. Pumpkin Seed Oil Extracted From Cucurbita maxima Improves Urinary Disorder in Human Overactive Bladder

    PubMed Central

    Nishimura, Mie; Ohkawara, Tatsuya; Sato, Hiroji; Takeda, Hiroshi; Nishihira, Jun

    2014-01-01

    The pumpkin seed oil obtained from Cucurbita pepo has been shown to be useful for the treatment of nocturia in patients with urinal disorders in several western countries. In this study, we evaluated the effect of the pumpkin seed oil from Cucurbita maxima on urinary dysfunction in human overactive bladder (OAB). Forty-five subjects were enrolled in this study. An extract of pumpkin seed oil from C. maxima (10 g of oil/day) was orally administrated for 12 weeks. After 6 and 12 weeks, urinary function was evaluated using Overactive Bladder Symptom Score (OABSS). Pumpkin seed oil from C. maxima significantly reduced the degree of OABSS in the subjects. The results from our study suggest that pumpkin seed oil extracts from C. maxima as well as from C. pepo are effective for urinary disorders such as OAB in humans. PMID:24872936

  20. Overexpression of the pumpkin (Cucurbita maxima) 16 kDa phloem protein CmPP16 increases tolerance to water deficit

    PubMed Central

    Ramírez-Ortega, Francisco Arturo; Herrera-Pola, Paul Starsky; Toscano-Morales, Roberto; Xoconostle-Cázares, Beatriz; Ruiz-Medrano, Roberto

    2014-01-01

    The phloem plays an important role in the delivery of nutrients and signals between photosynthetic to heterotrophic tissues. Proteins and RNAs in the phloem translocation stream may have an important role in maintaining the integrity of the sieve tube system, as well as in long-distance signaling. CmPP16 is a pumpkin phloem protein, which has been shown to bind RNA in a non-sequence specific manner, and move it cell-to-cell and conceivably, long-distance. The protein and RNA are found in both companion cell (CC) and sieve elements (SE). However, a more precise function for this protein is not known. In this work we report the overexpression of CmPP16 fused to GFP via transformation of pumpkin (Cucurbita maxima cv. Big Max) plants in the cotyledonary stage by direct inoculation of Agrobacterium tumefaciens and Agrobacterium rhizogenes. Plants overexpressing CmPP16 did not show an obvious phenotype. However, these plants displayed higher photosynthetic capacity during drought than wild-type (WT) pumpkin or transformed with another construct. These results suggest that CmPP16 may be involved in the response to stress through long-distance signaling. PMID:25482781

  1. Comparison of the chemical compositions and nutritive values of various pumpkin (Cucurbitaceae) species and parts.

    PubMed

    Kim, Mi Young; Kim, Eun Jin; Kim, Young-Nam; Choi, Changsun; Lee, Bog-Hieu

    2012-02-01

    Pumpkins have considerable variation in nutrient contents depending on the cultivation environment, species, or part. In this study, the general chemical compositions and some bioactive components, such as tocopherols, carotenoids, and β-sitosterol, were analyzed in three major species of pumpkin (Cucurbitaceae pepo, C. moschata, and C. maxima) grown in Korea and also in three parts (peel, flesh, and seed) of each pumpkin species. C. maxima had significantly more carbohydrate, protein, fat, and fiber than C. pepo or C. moschata (P < 0.05). The moisture content as well as the amino acid and arginine contents in all parts of the pumpkin was highest in C. pepo. The major fatty acids in the seeds were palmitic, stearic, oleic, and linoleic acids. C. pepo and C. moschata seeds had significantly more γ-tocopherol than C. maxima, whose seeds had the highest β-carotene content. C. pepo seeds had significantly more β-sitosterol than the others. Nutrient compositions differed considerably among the pumpkin species and parts. These results will be useful in updating the nutrient compositions of pumpkin in the Korean food composition database. Additional analyses of various pumpkins grown in different years and in different areas of Korea are needed. PMID:22413037

  2. The antiatherogenic, renal protective and immunomodulatory effects of purslane, pumpkin and flax seeds on hypercholesterolemic rats

    PubMed Central

    Barakat, Lamiaa A.A.; Mahmoud, Rasha Hamed

    2011-01-01

    Background: Atherosclerosis remains one of the leading causes of death all over the world. Flax, pumpkin and purslane seeds are rich sources of unsaturated fatty acids, antioxidants and fibers, known to have antiatherogenic activities. Aims: This study was to examine the efficiency of using either flax/pumpkin or purslane/pumpkin seed mixture (components of ω-3 and ω-6) on hyperlipidemia, kidney function and as immunomodulators in rats fed high cholesterol diets. Materials and Methods: 40 male albino rats were divided into four groups: control group, hypercholesterolemic rats, fed the balanced diet supplemented with cholesterol at a dose level of 2 g/100 g diet; the other two groups of animals fed the same previous hypercholesterolemic diet supplemented with either flax/pumpkin seed mixture or pumpkin/purslane seed mixture at ratio of (5/1) (ω-3 and ω-6). Results: The present study showed that 2% cholesterol administration caused a significant increase in total cholesterol, total lipids, and triacylglycerol in both serum and liver. Serum phospholipids, LDL-C, and atherogenic index AI also significantly increased compared to control group. Cholesterol-enriched diet significantly increased serum urea, creatinine, sodium and potassium levels as well as significantly increased serum IgG and IgM compared to healthy control. Consumption of flax/pumpkin or purslane/pumpkin seed mixtures by hypercholesterolemic rats resulted in a significantly decrement in lipid parameters and significant improvement in IgG and IgM levels as compared with hypercholesterolemic rats. Conclusion: Our results suggests that both flax/pumpkin and purslane/pumpkin seed mixtures had anti-atherogenic hypolipidemic and immunmodulator effects which were probably mediated by unsaturated fatty acids (including alpha linolenic acid) present in seed mixture. PMID:22362450

  3. Sequence variations in the FAD2 gene in seeded pumpkins.

    PubMed

    Ge, Y; Chang, Y; Xu, W L; Cui, C S; Qu, S P

    2015-01-01

    Seeded pumpkins are important economic crops; the seeds contain various unsaturated fatty acids, such as oleic acid and linoleic acid, which are crucial for human and animal nutrition. The fatty acid desaturase-2 (FAD2) gene encodes delta-12 desaturase, which converts oleic acid to linoleic acid. However, little is known about sequence variations in FAD2 in seeded pumpkins. Twenty-seven FAD2 clones from 27 accessions of Cucurbita moschata, Cucurbita maxima, Cucurbita pepo, and Cucurbita ficifolia were obtained (totally 1152 bp; a single gene without introns). More than 90% nucleotide identities were detected among the 27 FAD2 clones. Nucleotide substitution, rather than nucleotide insertion and deletion, led to sequence polymorphism in the 27 FAD2 clones. Furthermore, the 27 FAD2 selected clones all encoded the FAD2 enzyme (delta-12 desaturase) with amino acid sequence identities from 91.7 to 100% for 384 amino acids. The same main-function domain between 47 and 329 amino acids was identified. The four species clustered separately based on differences in the sequences that were identified using the unweighted pair group method with arithmetic mean. Geographic origin and species were found to be closely related to sequence variation in FAD2. PMID:26782391

  4. Certain functional properties of defatted pumpkin seed flour.

    PubMed

    Lazos, E S

    1992-07-01

    Defatted pumpkin (C. pepo and C. maxima) seed flour has potential food uses because of its high protein content, 61.4 +/- 2.56%. The functional and electrophoretic properties of the defatted flour were investigated. Polyacrylamide gel electrophoresis and electrofocusing indicated 14 bands of water-soluble protein subunits with isoelectric points between 3.81-8.08 and apparent molecular weights between 19,200 and 97,000 daltons. Minimum nitrogen solubility was observed at pH values between 3.0-7.0 and exceeded 90% at pH above 9.0. Solubility was a function of ionic strength. It appeared that, even at the pH of minimum solubility, the pumpkin seed proteins could be dissolved up to high concentrations by increasing NaCl molarity. The viscosity of flour-water dispersion was affected by flour and salt concentrations, and temperature. The least gelation concentration was 8% (w/v) and the water and oil absorption 24.8 +/- 2.03 and 84.4 +/- 4.05 g/100 g respectively. Sorption isotherms, BET monolayer moisture and binding energy of sorption were also calculated. Both foam capacity and stability were pH dependent. PMID:1502127

  5. Comparison of waste pumpkin material and its potential use in extruded snack foods.

    PubMed

    Norfezah, M N; Hardacre, A; Brennan, C S

    2011-08-01

    Material was produced from Crown pumpkin (Cucurbita maxima) processed from fractions of the fruit which are regarded as waste stream products (peel, flesh and seed). The flour from the three different fractions (peel, flesh and seed) of Crown pumpkin flour was incorporated into an extruded snack product formulation at levels 10%, 30% and 50% (w/w with corn grit) and processed in a twin-screw extruder to make 10 expanded snack products. Proximate analysis was carried out to determine the nutritional value of the raw pumpkin and pumpkin flour. A physical analysis of the product was used to determine its color, the expansion ratio, bulk density and texture. Inclusion of waste stream material (peel and seed) at 10%, yielded extruded products with similar expansion and density characteristics to the control sample; however, an inclusion of greater than 10% yielded significant challenges to product quality (hardness of the product). PMID:21813596

  6. Characteristics and composition of watermelon, pumpkin, and paprika seed oils and flours.

    PubMed

    El-Adawy, T A; Taha, K M

    2001-03-01

    The nutritional quality and functional properties of paprika seed flour and seed kernel flours of pumpkin and watermelon were studied, as were the characteristics and structure of their seed oils. Paprika seed and seed kernels of pumpkin and watermelon were rich in oil and protein. All flour samples contained considerable amounts of P, K, Mg, Mn, and Ca. Paprika seed flour was superior to watermelon and pumpkin seed kernel flours in content of lysine and total essential amino acids. Oil samples had high amounts of unsaturated fatty acids with linoleic and oleic acids as the major acids. All oil samples fractionated into seven classes including triglycerides as a major lipid class. Data obtained for the oils' characteristics compare well with those of other edible oils. Antinutritional compounds such as stachyose, raffinose, verbascose, trypsin inhibitor, phytic acid, and tannins were detected in all flours. Pumpkin seed kernel flour had higher values of chemical score, essential amino acid index, and in vitro protein digestibility than the other flours examined. The first limiting amino acid was lysine for both watermelon and pumpkin seed kernel flours, but it was leucine in paprika seed flour. Protein solubility index, water and fat absorption capacities, emulsification properties, and foam stability were excellent in watermelon and pumpkin seed kernel flours and fairly good in paprika seed flour. Flour samples could be potentially added to food systems such as bakery products and ground meat formulations not only as a nutrient supplement but also as a functional agent in these formulations. PMID:11312845

  7. Ectopic Expression of Pumpkin Gibberellin Oxidases Alters Gibberellin Biosynthesis and Development of Transgenic Arabidopsis Plants1

    PubMed Central

    Radi, Abeer; Lange, Theo; Niki, Tomoya; Koshioka, Masaji; Lange, Maria João Pimenta

    2006-01-01

    Immature pumpkin (Cucurbita maxima) seeds contain gibberellin (GA) oxidases with unique catalytic properties resulting in GAs of unknown function for plant growth and development. Overexpression of pumpkin GA 7-oxidase (CmGA7ox) in Arabidopsis (Arabidopsis thaliana) resulted in seedlings with elongated roots, taller plants that flower earlier with only a little increase in bioactive GA4 levels compared to control plants. In the same way, overexpression of the pumpkin GA 3-oxidase1 (CmGA3ox1) resulted in a GA overdose phenotype with increased levels of endogenous GA4. This indicates that, in Arabidopsis, 7-oxidation and 3-oxidation are rate-limiting steps in GA plant hormone biosynthesis that control plant development. With an opposite effect, overexpression of pumpkin seed-specific GA 20-oxidase1 (CmGA20ox1) in Arabidopsis resulted in dwarfed plants that flower late with reduced levels of GA4 and increased levels of physiological inactive GA17 and GA25 and unexpected GA34 levels. Severe dwarfed plants were obtained by overexpression of the pumpkin GA 2-oxidase1 (CmGA2ox1) in Arabidopsis. This dramatic change in phenotype was accompanied by a considerable decrease in the levels of bioactive GA4 and an increase in the corresponding inactivation product GA34 in comparison to control plants. In this study, we demonstrate the potential of four pumpkin GA oxidase-encoding genes to modulate the GA plant hormone pool and alter plant stature and development. PMID:16384902

  8. Inhibition of testosterone-induced hyperplasia of the prostate of sprague-dawley rats by pumpkin seed oil.

    PubMed

    Gossell-Williams, M; Davis, A; O'Connor, N

    2006-01-01

    The oil from the pumpkin (Cucurbita pepo) seed is claimed to be useful in the management of benign prostatic hyperplasia. This investigation seeks to examine the effect of pumpkin seed oil on testosterone-induced hyperplasia of the prostate of rats. Hyperplasia was induced by subcutaneous administration of testosterone (0.3 mg/100 g of body weight) for 20 days. Simultaneous oral administration of either pumpkin seed oil (2.0 and 4.0 mg/100 g of body weight) or corn oil (vehicle) was also given for 20 days. The weights of the rats were recorded weekly, and the influence of testosterone and pumpkin seed oil on the weight gain of the rats was examined. On day 21, rats were sacrificed, and the prostate was removed, cleaned, and weighed. The prostate size ratio (prostate weight/rat body weight) was then calculated. Neither testosterone nor pumpkin seed oil had any significant influence on the weight gain of the rats. Testosterone significantly increased prostate size ratio (P < .05), and this induced increase was inhibited in rats fed with pumpkin seed oil at 2.0 mg/100 g of body weight. The protective effect of pumpkin seed oil was significant at the higher pumpkin seed oil dose (P < .02). We conclude pumpkin seed oil can inhibit testosterone-induced hyperplasia of the prostate and therefore may be beneficial in the management of benign prostatic hyperplasia. PMID:16822218

  9. Design Evolution and Methodology for Pumpkin Super-Pressure Balloons

    NASA Astrophysics Data System (ADS)

    Farley, Rodger

    The NASA Ultra Long Duration Balloon (ULDB) program has had many technical development issues discovered and solved along its road to success as a new vehicle. It has the promise of being a sub-satellite, a means to launch up to 2700 kg to 33.5 km altitude for 100 days from a comfortable mid-latitude launch point. Current high-lift long duration ballooning is accomplished out of Antarctica with zero-pressure balloons, which cannot cope with the rigors of diurnal cycles. The ULDB design is still evolving, the product of intense analytical effort, scaled testing, improved manufacturing, and engineering intuition. The past technical problems, in particular the s-cleft deformation, their solutions, future challenges, and the methodology of pumpkin balloon design will generally be described.

  10. Modulations of RNA sequences by cytokinin in pumpkin cotyledons

    SciTech Connect

    Chang, C.; Ertl, J.; Chen, C.

    1987-04-01

    Polyadenylated mRNAs from excised pumpkin cotyledons treated with or without 10/sup -4/ M benzyladenine (BA) for various time periods in suspension culture were assayed by in vitro translation in the presence of (/sup 35/S) methionine. The radioactive polypeptides were analyzed by one- and two-dimensional polyacrylamide gel electrophoresis. Specific sequences of mRNAs were enhanced, reduced, induced, or suppressed by the hormone within 60 min of the application of BA to the cotyledons. Four independent cDNA clones of cytokinin-modulated mRNAs have been selected and characterized. RNA blot hybridization using the four cDNA probes also indicates that the levels of specific mRNAs are modulated upward or downward by the hormone.

  11. Effect of NPK fertilizer on chemical composition of pumpkin (Cucurbita pepo Linn.) seeds.

    PubMed

    Oloyede, F M; Obisesan, I O; Agbaje, G O; Obuotor, E M

    2012-01-01

    An investigation of the proximate composition and antioxidant profile of pumpkin seeds obtained from different levels of NPK 15 : 15 : 15 compound fertilizer application at the Obafemi Awolowo University, Ile-Ife, Nigeria was carried out. Pumpkin seeds were grown in 2010 for two cropping seasons (May to August and August to November), and the following fertilizer rates were applied: 0, 50, 100, 150, 200, and 250 kg/ha. Standard analytical methods were used to determine protein, crude fibre, ash, fat, carbohydrate, antioxidant activities, phenol, flavonoid, proanthocyanidin, and anthocyanin. The highest concentrations of the proximate and antioxidants analysed were found from the seeds of control and those treated with lower NPK rates. The mean protein, ash, crude fibre, and carbohydrate values of pumpkin seeds at zero to 100 kg NPK/ha were 27%, 1.56%, 0.56%, and 11.7% respectively. At these same levels of fertilizer, pumpkin seed oil yield was 59%. Antioxidant activities ranged from 89.9 to 90.4% while total phenol was 47 mg/100 g. Except for carbohydrate, the % concentration of nutrients and antioxidants in pumpkin seeds was significantly (P = 0.05) depressed with fertilizer rates above 100 g/ha. PMID:22629204

  12. Characteristics of antioxidant activity and composition of pumpkin seed oils in 12 cultivars.

    PubMed

    Nawirska-Olszańska, Agnieszka; Kita, Agnieszka; Biesiada, Anita; Sokół-Łętowska, Anna; Kucharska, Alicja Z

    2013-08-15

    The objective of this study was to determine the antioxidant properties, and provide characteristics, of the oil obtained from the seeds of 12 pumpkin varieties belonging to the species Cucurbita maxima Duch. and Cucurbita pepo L. Another objective was to establish which of the two extracting agents, ethanol or methanol, is more effective. The seeds of the pumpkin varieties examined differ in chemical composition and antioxidant activity. The seeds of the cultivars belonging to the species C. maxima are characterised by a higher content of fatty acids than are the cultivars of the species C. pepo. In the seed oil, unsaturated acids are dominant (oleic and linoleic), and their proportion depends on the pumpkin variety. The highest content of unsaturated acids has been measured in the oil extracted from the seeds of the cultivar, Jet F1 (C. pepo). Antioxidant activity analysis has produced the following findings. The seeds of the pumpkin varieties that belong to the species C. pepo exhibit better antioxidant properties, regardless of the extraction solvent used. 50% ethanol is more efficient than 80% methanol when used as an extracting agent. The antioxidant activity values obtained with 50% ethanol are higher than those achieved with 80% methanol. Owing to the considerable differences in composition among the fatty acids examined, it is possible to choose the desired pumpkin variety for the intended use. PMID:23561092

  13. Production of Dwarf Lettuce by Overexpressing a Pumpkin Gibberellin 20-Oxidase Gene

    PubMed Central

    Niki, Tomoya; Nishijima, Takaaki; Nakayama, Masayoshi; Hisamatsu, Tamotsu; Oyama-Okubo, Naomi; Yamazaki, Hiroko; Hedden, Peter; Lange, Theo; Mander, Lewis N.; Koshioka, Masaji

    2001-01-01

    We investigated the effect of overexpressing a pumpkin gibberellin (GA) 20-oxidase gene encoding an enzyme that forms predominantly biologically inactive products on GA biosynthesis and plant morphology in transgenic lettuce (Lactuca sativa cv Vanguard) plants. Lettuce was transformed with the pumpkin GA 20-oxidase gene downstream of a strong constitutive promoter cassette (El2–35S-Ω). The transgenic plants in which the pumpkin gene was detected by polymerase chain reaction were dwarfed in the T2 generation, whereas transformants with a normal growth phenotype did not contain the transgene. The result of Southern-blot analysis showed that the transgene was integrated as a single copy; the plants segregated three dwarfs to one normal in the T2 generation, indicating that the transgene was stable and dominant. The endogenous levels of GA1 and GA4 were reduced in the dwarfs, whereas large amounts of GA17 and GA25, which are inactive products of the pumpkin GA 20-oxidase, accumulated in these lines. These results indicate that a functional pumpkin GA 20-oxidase is expressed in the transgenic lettuce, resulting in a diversion of the normal pathway of GA biosynthesis to inactive products. Furthermore, this technique may be useful for controlling plant stature in other agricultural and horticultural species. PMID:11457947

  14. Production of dwarf lettuce by overexpressing a pumpkin gibberellin 20-oxidase gene.

    PubMed

    Niki, T; Nishijima, T; Nakayama, M; Hisamatsu, T; Oyama-Okubo, N; Yamazaki, H; Hedden, P; Lange, T; Mander, L N; Koshioka, M

    2001-07-01

    We investigated the effect of overexpressing a pumpkin gibberellin (GA) 20-oxidase gene encoding an enzyme that forms predominantly biologically inactive products on GA biosynthesis and plant morphology in transgenic lettuce (Lactuca sativa cv Vanguard) plants. Lettuce was transformed with the pumpkin GA 20-oxidase gene downstream of a strong constitutive promoter cassette (El2-35S-Omega). The transgenic plants in which the pumpkin gene was detected by polymerase chain reaction were dwarfed in the T(2) generation, whereas transformants with a normal growth phenotype did not contain the transgene. The result of Southern-blot analysis showed that the transgene was integrated as a single copy; the plants segregated three dwarfs to one normal in the T(2) generation, indicating that the transgene was stable and dominant. The endogenous levels of GA(1) and GA(4) were reduced in the dwarfs, whereas large amounts of GA(17) and GA(25), which are inactive products of the pumpkin GA 20-oxidase, accumulated in these lines. These results indicate that a functional pumpkin GA 20-oxidase is expressed in the transgenic lettuce, resulting in a diversion of the normal pathway of GA biosynthesis to inactive products. Furthermore, this technique may be useful for controlling plant stature in other agricultural and horticultural species. PMID:11457947

  15. Suitability of elemental fingerprinting for assessing the geographic origin of pumpkin (Cucurbita pepo var. styriaca) seed oil.

    PubMed

    Bandoniene, Donata; Zettl, Daniela; Meisel, Thomas; Maneiko, Marija

    2013-02-15

    An analytical method was developed and validated for the classification of the geographical origin of pumpkin seeds and oil from Austria, China and Russia. The distribution of element traces in pumpkin seed and pumpkin seed oils in relation to the geographical origin of soils of several agricultural farms in Austria was studied in detail. Samples from several geographic origins were taken from parts of the pumpkin, pumpkin flesh, seeds, the oil extracted from the seeds and the oil-extraction cake as well as the topsoil on which the plants were grown. Plants from different geographical origin show variations of the elemental patterns that are significantly large, reproducible over the years and ripeness period and show no significant influence of oil production procedure, to allow to a discrimination of geographical origin. A successful differentiation of oils from different regions in Austria, China and Russia classified with multivariate data analysis is demonstrated. PMID:23194559

  16. Growth Mechanism of Pumpkin-Shaped Vaterite Hierarchical Structures

    NASA Astrophysics Data System (ADS)

    Ma, Guobin; Xu, Yifei; Wang, Mu

    2015-03-01

    CaCO3-based biominerals possess sophisticated hierarchical structures and promising mechanical properties. Recent researches imply that vaterite may play an important role in formation of CaCO3-based biominerals. However, as a less common polymorph of CaCO3, the growth mechanism of vaterite remains not very clear. Here we report the growth of a pumpkin-shaped vaterite hierarchical structure with a six-fold symmetrical axis and lamellar microstructure. We demonstrate that the growth is controlled by supersaturation and the intrinsic crystallographic anisotropy of vaterite. For the scenario of high supersaturation, the nucleation rate is higher than the lateral extension rate, favoring the ``double-leaf'' spherulitic growth. Meanwhile, nucleation occurs preferentially in < 11 2 0 > as determined by the crystalline structure of vaterite, modulating the grown products with a hexagonal symmetry. The results are beneficial for an in-depth understanding of the biomineralization of CaCO3. The growth mechanism may also be applicable to interpret the formation of similar hierarchical structures of other materials. The authors gratefully acknowledge the financial support from National Science Foundation of China (Grant Nos. 51172104 and 50972057) and National Key Basic Research Program of China (Grant No. 2010CB630705).

  17. Square concrete culvert and concrete retaining wall, 1/2 mile east ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Square concrete culvert and concrete retaining wall, 1/2 mile east of Indigo Tunnel, milepost 128. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

  18. Microbiological and physicochemical analysis of pumpkin juice fermentation by the basidiomycetous fungus Ganoderma lucidum.

    PubMed

    Zhao, Jing; Liu, Wei; Chen, Dong; Zhou, Chunli; Song, Yi; Zhang, Yuyu; Ni, Yuanying; Li, Quanhong

    2015-02-01

    A new protocol for processing of pumpkin juice was set up which included fermentation by the basidiomycete Ganoderma lucidum at 28 °C for 7 d. The growth curve of G. lucidum in pumpkin juice was successfully (R(2)  = 0.99) fitted by a 4-parameter logistic model and the ideal highest biomass was estimated to be 4.79 g/L. G. lucidum was found to have a significant acidification effect on pumpkin juice. The lowest pH (4.05 ± 0.05) and highest total titratable acidity (14.31 ± 0.16 mL 0.1 M NaOH/100 mL) were found on the 4th day during fermentation. Sugars in pumpkin juice fermented with G. lucidum showed a significant decrease, especially glucose and fructose. On the contrary, the release of exo-polysaccharides and free amino acids greatly enriched the pumpkin juice. The variation of color index and viscosity also mirrored the above behavior. Based on headspace solid phase microextraction and gas chromatography-mass spectrometry, 68 volatile compounds were identified, including 17 esters, 14 alcohols, 13 phenyl compounds, 11 aldehydes, 8 ketones, 3 acids, 1 furan, and 1 benzothiazole. The pumpkin juices fermented for different days were markedly differentiated with principal component analysis and the fermentation process was tentatively divided into 3 periods: the booming (from the 1st to 4th day), steady (from the 5th to 6th day), and decline (the 7th day) period. PMID:25586306

  19. Use of lablab (Lablab purpureus (L.) Sweet) for bio-control by native arthropods and its effect on yield of pumpkins.

    PubMed

    Qureshi, S A; Angove, M; Wilkens, S; Midmore, D J

    2016-04-01

    Silverleaf whitefly (SLW, Bemisia tabaci MEAM1) and aphids are sap-sucking insects, which pose a serious threat to Australian cucurbit crops and the horticulture industry. Traditional chemical control for these insect pests is becoming less effective, and there is a need to search for alternative or supplementary methods. This study aimed to manipulate the habitat of pumpkin crops in a tropical setting (Queensland, Australia), by growing pumpkins (var. Japanese pumpkin) alone and between lablab (Lablab purpureus L. Sweet). It was hypothesized that the presence of lablab will increase the populations of natural enemies, and through their control of insect pests such as SLW and aphids, will affect pumpkin yield. The population of arthropods (natural enemies and pests of pumpkin), with a focus on SLW and aphids, were sampled weekly on both lablab and pumpkin crop for a total of 21 weeks. Results showed that lablab hosted more enemies of SLW per plant than pumpkin in either treatment. In addition, adult SLW numbers were significantly higher in the pumpkin-only crop compared with the pumpkin grown between lablab, while pumpkin in the mixed plantings had significantly more ladybirds and lacewing larvae (P < 0.05). While there was no significant difference in the average fruit weight between treatments, the total weight (kg) and number of marketable pumpkins per hectare was greater (P < 0.05) for the pumpkin/lablab treatment than the pumpkin-only treatment. This study shows that growing lablab alongside a pumpkin crop may enhance natural enemies of SLW and could significantly increase the yield. PMID:26693799

  20. Material Properties Analysis of Structural Members in Pumpkin Balloons

    NASA Technical Reports Server (NTRS)

    Sterling, W. J.

    2003-01-01

    The efficient design, service-life qualification, and reliability predictions for lightweight aerospace structures require careful mechanical properties analysis of candidate structural materials. The demand for high-quality laboratory data is particularly acute when the candidate material or the structural design has little history. The pumpkin-shaped super-pressure balloon presents both challenges. Its design utilizes load members (tendons) extending from apex to base around the gas envelope to achieve a lightweight structure. The candidate tendon material is highly weight-efficient braided HM cord. Previous mechanical properties studies of Zylon have focused on fiber and yarn, and industrial use of the material in tensile applications is limited. For high-performance polymers, a carefully plamed and executed properties analysis scheme is required to ensure the data are relevant to the desired application. Because no directly-applicable testing standard was available, a protocol was developed based on guidelines fiom professional and industry organizations. Due to the liquid-crystalline nature of the polymer, the cord is very stiff, creeps very little, and does not yield. Therefore, the key material property for this application is the breaking strength. The pretension load and gauge length were found to have negligible effect on the measured breaking strength over the ranges investigated. Strain rate was found to have no effect on breaking strength, within the range of rates suggested by the standards organizations. However, at the lower rate more similar to ULDB operations, the strength was reduced. The breaking strength increased when the experiment temperature was decreased from ambient to 183K which is the lowest temperature ULDB is expected to experience. The measured strength under all test conditions was well below that resulting from direct scale-up of fiber strength based on the manufacturers data. This expected result is due to the effects of the

  1. Dropping Knowledge Like Frozen Pumpkins: Successful Physics Outreach

    NASA Astrophysics Data System (ADS)

    Hook, E. A.

    2011-12-01

    The Society of Physics Students (SPS) is a professional organization specifically designed for college students. A main purpose of SPS is to develop college students into effective members of the physics community; one of the best ways to do this is by promoting science outreach. College students are in a prime position to engage the public in outreach to increase scientific literacy: they're easier for younger, school-age students to identify with, they can reach young adults in a unique way, and they're old enough to seriously engage the general public. SPS helps hundreds of college chapters across the country engage in outreach. One such chapter is at Rhodes College in Memphis, TN. The Rhodes College SPS chapter is active both in K12 schools and on its campus. Rhodes developed a position within its SPS structure to include an officer specifically related to handling outreach. For K12 schools this involved contacting teachers, organizing lessons, and holding training sessions for the college students preparing to teach the lessons. Rhodes SPS also focuses on campus outreach and trying to disabuse students of the notion that physics is stuffy, boring, and only for geniuses. Every fall, Rhodes SPS hosts an extremely popular annual Pumpkin Drop, as well as hosting demo shows, observatory open houses, and contests throughout the year for its students. One of the best received campus outreach programs is something called 'Stall Stories,' where SPS publishes a page flyer that goes in bathrooms around campus involving fun physics, a comic, and a list of SPS events. Rhodes SPS, like the national organization, has the goal of improving physics literacy among K12 students, college students, and the general public through effective outreach.

  2. Geology of the Pumpkin Buttes Area of the Powder River Basin, Campbell and Johnson Counties, Wyoming

    USGS Publications Warehouse

    Sharp, William Neil; White, Amos McNairy

    1956-01-01

    About 200 uranium occurrences have been examined in the Pumpkin Buttes area, Wyoming. Uranium minerals are visible at most of these places and occur in red and buff sandstone lenses in the Wasatch formation of Eocene age. The uranium minerals are disseminated in buff sandstone near red sandstone, and also occur in red sandstone in manganese oxide concretions and uraninite concretions.

  3. Supercritical Carbon Dioxide Extraction of Carotenoids from Pumpkin (Cucurbita spp.): A Review

    PubMed Central

    Durante, Miriana; Lenucci, Marcello Salvatore; Mita, Giovanni

    2014-01-01

    Carotenoids are well known for their nutritional properties and health promoting effects representing attractive ingredients to develop innovative functional foods, nutraceutical and pharmaceutical preparations. Pumpkin (Cucurbita spp.) flesh has an intense yellow/orange color owing to the high level of carotenoids, mainly α-carotene, β-carotene, β-cryptoxanthin, lutein and zeaxanthin. There is considerable interest in extracting carotenoids and other bioactives from pumpkin flesh. Extraction procedures able to preserve nutritional and pharmacological properties of carotenoids are essential. Conventional extraction methods, such as organic solvent extraction (CSE), have been used to extract carotenoids from plant material for a long time. In recent years, supercritical carbon dioxide (SC-CO2) extraction has received a great deal of attention because it is a green technology suitable for the extraction of lipophylic molecules and is able to give extracts of high quality and totally free from potentially toxic chemical solvents. Here, we review the results obtained so far on SC-CO2 extraction efficiency and quali-quantitative composition of carotenoids from pumpkin flesh. In particular, we consider the effects of (1) dehydration pre-treatments; (2) extraction parameters (temperature and pressure); the use of water, ethanol and olive oil singularly or in combination as entrainers or pumpkin seeds as co-matrix. PMID:24756094

  4. Variability of vitamin E content in pumpkin seeds (Cucurbita pepo L.).

    PubMed

    Murkovic, M; Hillebrand, A; Winkler, J; Pfannhauser, W

    1996-04-01

    Pumpkin (Cucurbita pepo L.) seed oil is a common salad oil which is produced in the southern parts of Austria, Slovenia and Hungary. It is dark green and has a high content of free fatty acids. Due to its colour, the oil cannot be used for cooking. The content of vitamin E, especially gamma-tocopherol, is very high. The oil content of the pumpkin seed is about 50%. The seed itself can be eaten. Therefore a pumpkin variety with high vitamin E content is desirable. The aim of this work was to find a variety of Cucurbita pepo which has a high oil yield and a high vitamin E content. A total of 100 breeding lines were tested for their tocopherol content. The tocopherols and tocotrienols are extracted with hexane and analysed by NP-HPLC/FLD with hexane/dioxan (96/4) as eluent, with fluorescence detection at 292/335 nm. The gamma-tocopherol content, which is about 5-10 times as much as that of alpha-tocopherol varies over a broad range (41-620 mg/kg dry pumpkin seeds). Beta- and delta-tocopherol are found at low levels. PMID:8638429

  5. Optimization of hull-less pumpkin seed roasting conditions using response surface methodology.

    PubMed

    Vujasinović, Vesna; Radočaj, Olga; Dimić, Etelka

    2012-05-01

    Response surface methodology (RSM) was applied to optimize hull-less pumpkin seed roasting conditions before seed pressing to maximize the biochemical composition and antioxidant capacity of the virgin pumpkin oils obtained using a hydraulic press. Hull-less pumpkin seeds were roasted for various lengths of time (30 to 70 min) at various roasting temperatures (90 to 130 °C), resulting in 9 different oil samples, while the responses were phospholipids content, total phenols content, α- and γ-tocopherols, and antioxidative activity [by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical assay]. Mathematical models have shown that roasting conditions influenced all dependent variables at P < 0.05. The higher roasting temperatures had a significant effect (P < 0.05) on phospholipids, phenols, and α-tocopherols contents, while longer roasting time had a significant effect (P < 0.05) on γ-tocopherol content and antioxidant capacity, among the samples prepared under different roasting conditions. The optimum conditions for roasting the hull-less pumpkin seeds were 120 °C for duration of 49 min, which resulted in these oil concentrations: phospholipids 0.29%, total phenols 23.06 mg/kg, α-tocopherol 5.74 mg/100 g, γ-tocopherol 24.41 mg/100 g, and an antioxidative activity (EC(50)) of 27.18 mg oil/mg DPPH. PMID:23163936

  6. OIL AND TOCOPHEROL CONTENT AND COMPOSITION OF PUMPKIN SEED OIL IN TWELVE CULTIVARS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twelve pumpkin cultivars (Cucurbita maxima D.), cultivated in Iowa, were studied for their seed oil content, fatty acid composition and tocopherol content. Oil content ranged from 11 to 31%. Total unsaturated fatty acid content ranged from 73.1-80.5%. The predominant fatty acids present were linol...

  7. Supercritical carbon dioxide extraction of carotenoids from pumpkin (Cucurbita spp.): a review.

    PubMed

    Durante, Miriana; Lenucci, Marcello Salvatore; Mita, Giovanni

    2014-01-01

    Carotenoids are well known for their nutritional properties and health promoting effects representing attractive ingredients to develop innovative functional foods, nutraceutical and pharmaceutical preparations. Pumpkin (Cucurbita spp.) flesh has an intense yellow/orange color owing to the high level of carotenoids, mainly α-carotene, β-carotene, β-cryptoxanthin, lutein and zeaxanthin. There is considerable interest in extracting carotenoids and other bioactives from pumpkin flesh. Extraction procedures able to preserve nutritional and pharmacological properties of carotenoids are essential. Conventional extraction methods, such as organic solvent extraction (CSE), have been used to extract carotenoids from plant material for a long time. In recent years, supercritical carbon dioxide (SC-CO2) extraction has received a great deal of attention because it is a green technology suitable for the extraction of lipophylic molecules and is able to give extracts of high quality and totally free from potentially toxic chemical solvents. Here, we review the results obtained so far on SC-CO2 extraction efficiency and quali-quantitative composition of carotenoids from pumpkin flesh. In particular, we consider the effects of (1) dehydration pre-treatments; (2) extraction parameters (temperature and pressure); the use of water, ethanol and olive oil singularly or in combination as entrainers or pumpkin seeds as co-matrix. PMID:24756094

  8. Microbial diversity inside pumpkins: microhabitat-specific communities display a high antagonistic potential against phytopathogens.

    PubMed

    Fürnkranz, Michael; Lukesch, Birgit; Müller, Henry; Huss, Herbert; Grube, Martin; Berg, Gabriele

    2012-02-01

    Recent and substantial yield losses of Styrian oil pumpkin (Cucurbita pepo L. subsp. pepo var. styriaca Greb.) are primarily caused by the ascomycetous fungus Didymella bryoniae but bacterial pathogens are frequently involved as well. The diversity of endophytic microbial communities from seeds (spermosphere), roots (endorhiza), flowers (anthosphere), and fruits (carposphere) of three different pumpkin cultivars was studied to develop a biocontrol strategy. A multiphasic approach combining molecular, microscopic, and cultivation techniques was applied to select a consortium of endophytes for biocontrol. Specific community structures for Pseudomonas and Bacillus, two important plant-associated genera, were found for each microenvironment by fingerprinting of 16S ribosomal RNA genes. All microenvironments were dominated by bacteria; fungi were less abundant. Of the 2,320 microbial isolates analyzed in dual culture assays, 165 (7%) were tested positively for in vitro antagonism against D. bryoniae. Out of these, 43 isolates inhibited the growth of bacterial pumpkin pathogens (Pectobacterium carotovorum, Pseudomonas viridiflava, Xanthomonas cucurbitae); here only bacteria were selected. Microenvironment-specific antagonists were found, and the spermosphere and anthosphere were revealed as underexplored reservoirs for antagonists. In the latter, a potential role of pollen grains as bacterial vectors between flowers was recognized. Six broad spectrum antagonists selected according to their activity, genotypic diversity, and occurrence were evaluated under greenhouse conditions. Disease severity on pumpkins of D. bryoniae was significantly reduced by Pseudomonas chlororaphis treatment and by a combined treatment of strains (Lysobacter gummosus, P. chlororaphis, Paenibacillus polymyxa, and Serratia plymuthica). This result provides a promising prospect to biologically control pumpkin diseases. PMID:21947430

  9. The antioxidant effects of pumpkin seed oil on subacute aflatoxin poisoning in mice.

    PubMed

    Eraslan, Gökhan; Kanbur, Murat; Aslan, Öznur; Karabacak, Mürsel

    2013-12-01

    This study was aimed at the investigation of the antioxidant effect of pumpkin seed oil against the oxidative stress-inducing potential of aflatoxin. For this purpose, 48 male BALB/c mice were used. Four groups, each comprising 12 mice, were established. Group 1 was maintained as the control group. Group 2 was administered with pumpkin seed oil alone at a dose of 1.5 mL/kg.bw/day (∼1375mg/kg.bw/day). Group 3 received aflatoxin (82.45% AFB1 , 10.65% AFB2 , 4.13% AFG1, and 2.77% AFG2 ) alone at a dose of 625 μg/kg.bw/day. Finally, group 4 was given both 1.5 mL/kg.bw/day pumpkin seed oil and 625 μg/kg.bw/day aflatoxin. All administrations were oral, performed with the aid of a gastric tube and continued for a period of 21 days. At the end of day 21, the liver, lungs, kidneys, brain, heart, and spleen of the animals were excised, and the extirpated tissues were homogenized appropriately. Malondialdehyde (MDA) levels and catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were determined in tissue homogenates. In conclusion, it was determined that aflatoxin exhibited adverse effects on most of the oxidative stress markers. The administration of pumpkin seed oil diminished aflatoxin-induced adverse effects. In other words, the values of the group, which was administered with both aflatoxin and pumpkin seed oil, were observed to have drawn closer to the values of the control group. PMID:24591108

  10. Pollination Services Provided by Bees in Pumpkin Fields Supplemented with Either Apis mellifera or Bombus impatiens or Not Supplemented

    PubMed Central

    Petersen, Jessica D.; Reiners, Stephen; Nault, Brian A.

    2013-01-01

    Pollinators provide an important service in many crops. Managed honey bees (Apis mellifera L.) are used to supplement pollination services provided by wild bees with the assumption that they will enhance pollination, fruit set and crop yield beyond the levels provided by the wild bees. Recent declines in managed honey bee populations have stimulated interest in finding alternative managed pollinators to service crops. In the eastern U.S., managed hives of the native common eastern bumble bee (Bombus impatiens Cresson) may be an excellent choice. To examine this issue, a comprehensive 2-yr study was conducted to compare fruit yield and bee visits to flowers in pumpkin (Cucurbita pepo L.) fields that were either supplemented with A. mellifera hives, B. impatiens hives or were not supplemented. We compared pumpkin yield, A. mellifera flower visitation frequency and B. impatiens flower visitation frequency between treatments. Results indicated that supplementing pumpkin fields with either A. mellifera or B. impatiens hives did not increase their visitation to pumpkin flowers or fruit yield compared with those that were not supplemented. Next, the relationship between frequency of pumpkin flower visitation by the most prominent bee species (Peponapis pruinosa (Say), B. impatiens and A. mellifera) and fruit yield was determined across all pumpkin fields sampled. Fruit yield increased as the frequency of flower visits by A. mellifera and B. impatiens increased in 2011 and 2012, respectively. These results suggest that supplementation with managed bees may not improve pumpkin production and that A. mellifera and B. impatiens are important pollinators of pumpkin in our system. PMID:23894544

  11. Optimization of Preparation of Antioxidative Peptides from Pumpkin Seeds Using Response Surface Method

    PubMed Central

    Fan, Sanhong; Hu, Yanan; Li, Chen; Liu, Yanrong

    2014-01-01

    Protein isolates of pumpkin (Cucurbita pepo L) seeds were hydrolyzed by acid protease to prepare antioxidative peptides. The hydrolysis conditions were optimized through Box-Behnken experimental design combined with response surface method (RSM). The second-order model, developed for the DPPH radical scavenging activity of pumpkin seed hydrolysates, showed good fit with the experiment data with a high value of coefficient of determination (0.9918). The optimal hydrolysis conditions were determined as follows: hydrolyzing temperature 50°C, pH 2.5, enzyme amount 6000 U/g, substrate concentration 0.05 g/ml and hydrolyzing time 5 h. Under the above conditions, the scavenging activity of DPPH radical was as high as 92.82%. PMID:24637721

  12. Variability of fatty acid content in pumpkin seeds (Cucurbita pepo L.).

    PubMed

    Murkovic, M; Hillebrand, A; Winkler, J; Leitner, E; Pfannhauser, W

    1996-09-01

    Pumpkin (Cucurbita pepo L.) seed oil is a common salad oil which is produced in Slovenia, Hungary and the southern parts of Austria. It is dark green and has a high content of free fatty acids. The seed itself can be eaten. Due to its colour and the foam formation, the oil cannot be used for cooking. The content of vitamin E, especially gamma-tocopherol, is very high. The oil content of the pumpkin seed is about 50%. The variability in the oil content is very high resulting from a broad genetic diversity. Thus a breeding programme for increasing the oil productivity is very promising. The four dominant fatty acids are palmitic, stearic, oleic and linoleic acids. These four fatty acids make up 98 +/- 0.13% of the total amount of fatty acids, others being found at levels well below 0.5%. PMID:8873459

  13. Hemolytic crisis in a G6PD-deficient infant after ingestion of pumpkin

    PubMed Central

    2014-01-01

    A 8 month-old infant presented with acute onset of severe jaundice, anemia requiring transfusion and Glucose-6-Phosphate Dehydrogenase deficiency. The infant did not take drugs, he did not consume fava beans, but fava beans DNA was found on pumpkin he consumed the day before jaundice onset. This is the first case of hemolysis triggered by ingestion of food cross-contaminated with fava beans. PMID:25048415

  14. Effect of the extracts of pumpkin seeds on the urodynamics of rabbits: an experimental study.

    PubMed

    Zhang, X; Ouyang, J Z; Zhang, Y S; Tayalla, B; Zhou, X C; Zhou, S W

    1994-01-01

    Pumpkin seeds were prepared into oil n-butyle alcohol and ether extracts. The effects of the three extracts on the urodynamics of rabbits were observed. It was concluded that the oil preparation could remarkably reduce the bladder pressure, increase the bladder compliance, reduce the urethral pressure. Other two kinds of preparations had no effect in this experimental. The mechanisms of the effect of oil preparation on the urodynamics and the prospect of clinical use was discussed. PMID:7760436

  15. Summary of investigations of uranium deposits in the Pumpkin Buttes area, Johnson and Campbell Counties, Wyoming

    USGS Publications Warehouse

    Troyer, Max L.; McKay, Edward J.; Soister, Paul E.; Wallace, Stewart R.

    1953-01-01

    Uranium minerals were discovered in the Pumpkin Buttes area Campbell and Johnson Counties by the U.S. Geological Survey in October 1951 From June to November 1952 an area of about 750 square miles was examined for uranium deposits, and 211 localities with abnormally high radioactivity were found uranium minerals are visible at 121 of these localities. All known uranium mineralization is restricted to sandstones of the Wasatch formation exclusive of sparsely disseminated uranium in the White River sandstone which caps the Pumpkin Buttes and several localities on the Great Pine Ridge southwest of the Pumpkin Buttes where ironstone and clinker in the Fort Union formation have above normal radioactivity. The uranium occurrences in the Wasatch formation are in a red sandstone zone 450 to 900 feet above the base of formation and are of two types. (1) small concretionary masses of uranium, iron, and manganese minerals in sandstone and (2) irregular zones in which uranium minerals are disseminated in sandstone The second type is usually larger but lower grade than the first type. Most of the localities at which uranium occurs are in a north -trending belt approximately 60 miles long with a maximum width of 18 miles,

  16. Summary of investigations of uranium deposits in the Pumpkin Buttes area, Johnson and Campbell Counties, Wyoming

    USGS Publications Warehouse

    Troyer, Max L.; McKay, Edward J.; Soister, Paul E.; Wallace, Stewart R.

    1954-01-01

    Uranium minerals were discovered in the Pumpkin Buttes area, Campbell and Johnson Counties, Wyo., by the U. S. Geological Survey in October 1951. From June to November 1952, an area of about 750 square miles was examined for uranium deposits, and 211 localities having abnormally high radioactivity were found; uranium minerals are visible at 121 of these localities. All known uranium mineralization in the area is restricted to sandstones of the Wasatch formation, except sparsely disseminated uranium in the sandstone of the White River formation, which caps the Pumpkin Buttes, mid several localities on the Great Pine Ridge southwest of the Pumpkin Buttes where iron-saturated sandstone and clinker in the Fort Union formation have above-normal radioactivity. The uranium occurrences in the Wasatch formation are in a red sandstone zone 450 to 900 feet above the base of the formation and are of two types: small concretionary masses of uranium, iron, manganese and vanadium minerals in sandstone, and irregular zones in which uranium minerals are disseminated in sandstone. The second type is usually larger but of lower grade than the first. Most of the localities at which uranium occurs are in a north-trending belt about 60 miles long and 18 miles in maximum width.

  17. PumpKin: A tool to find principal pathways in plasma chemical models

    NASA Astrophysics Data System (ADS)

    Markosyan, Aram H.; Luque, Alejandro; Gordillo Vázquez, Francisco J.; Ebert, Ute

    2013-09-01

    Recent kinetic models of atmospheric chemistry or of many industrial processes contain thousands of chemical reactions and species. The reactions depend on timescales, electric fields, temperature, pressure etc. We have developed a software tool called PumpKin (pathway reduction method for plasma kinetic models) to find all principal pathways in such complex plasma chemistry models, i.e. the dominant reaction sequences. PumpKin is a universal tool, inspired by [Lehmann, J Atmos Chem 41, 297 (2002)]. It requires to define and to run once a complete plasma kinetics solver, e.g. ZDPlasKin [http://www.zdplaskin.laplace.univ-tlse.fr], up to the time of interest. The stoichiometric matrix of the system, the reaction rates and the temporal profile of the species densities are the input for PumpKin to systematically identify the principal pathways. AHM also acknowledges the support from European Science Foundation (ESF) for short visit grant 5297, within the ESF activity entitled ``Thunderstorm effects on the atmosphere-ionosphere system.''

  18. Pumpkin (Cucurbita maxima) seed proteins: sequential extraction processing and fraction characterization.

    PubMed

    Rezig, Leila; Chibani, Farhat; Chouaibi, Moncef; Dalgalarrondo, Michèle; Hessini, Kamel; Guéguen, Jacques; Hamdi, Salem

    2013-08-14

    Seed proteins extracted from Tunisian pumpkin seeds ( Cucurbita maxima ) were investigated for their solubility properties and sequentially extracted according to the Osborne procedure. The solubility of pumpkin proteins from seed flour was greatly influenced by pH changes and ionic strength, with higher values in the alkaline pH regions. It also depends on the seed defatting solvent. Protein solubility was decreased by using chloroform/methanol (CM) for lipid extraction instead of pentane (P). On the basis of differential solubility fractionation and depending on the defatting method, the alkali extract (AE) was the major fraction (42.1 (P), 22.3% (CM)) compared to the salt extract (8.6 (P), 7.5% (CM)). In salt, alkali, and isopropanol extracts, all essential amino acids with the exceptions of threonine and lysine met the minimum requirements for preschool children (FAO/WHO/UNU). The denaturation temperatures were 96.6 and 93.4 °C for salt and alkali extracts, respectively. Pumpkin protein extracts with unique protein profiles and higher denaturation temperatures could impart novel characteristics when used as food ingredients. PMID:23869935

  19. Subcellular distribution and uptake mechanism of di-n-butyl phthalate in roots of pumpkin (Cucurbita moschata) seedlings.

    PubMed

    Lin, Qingqi; Yang, Xiuhong; Huang, Xiongfei; Wang, Shizhong; Chao, Yuanqing; Qiu, Rongliang

    2016-01-01

    Phthalate acid esters (PAEs) are of particular concern due to their potential environmental risk to human and nonhuman organisms. Although uptake of PAEs by plants has been reported by several researchers, information about the intracellular distribution and uptake mechanisms of PAEs is still lacking. In this study, a series of hydroponic experiments using intact pumpkin (Cucurbita moschata) seedlings was conducted to investigate how di-n-butyl phthalate (DnBP), one of the most frequently identified PAEs in the environment, enters and is distributed in roots. DnBP was transported into subcellular tissues rapidly in the initial uptake period (<12 h). More than 80% of DnBP was detected in the cell walls and organelles, which suggests that DnBP is primarily accumulated in these two fractions due to their high affinity to DnBP. The kinetics of DnBP uptake were fitted well with the Michaelis-Menten equation, suggesting that a carrier-mediated process was involved. The application of 2,4-dinitrophenol and sodium vanadate reduced the uptake of DnBP by 37 and 26%, respectively, while aquaporin inhibitors, silver and glycerol, had no effect on DnBP uptake. These data demonstrated that the uptake of DnBP included a carrier-mediated and energy-dependent process without the participation of aquaporins. PMID:26304812

  20. Glyoxysomal malate dehydrogenase in pumpkin: cloning of a cDNA and functional analysis of its presequence.

    PubMed

    Kato, A; Takeda-Yoshikawa, Y; Hayashi, M; Kondo, M; Hara-Nishimura, I; Nishimura, M

    1998-02-01

    Glyoxysomal malate dehydrogenase (gMDH) is an enzyme of the glyoxylate cycle that participates in degradation of storage oil. We have cloned a cDNA for gMDH from etiolated pumpkin cotyledons that encodes a polypeptide consisting of 356 amino acid residues. The nucleotide and N-terminal amino acid sequences revealed that gMDH is synthesized as a precursor with an N-terminal extrapeptide. The N-terminal presequence of 36 amino acid residues contains two regions homologous to those of other microbody proteins, which are also synthesized as large precursors. To investigate the functions of the N-terminal presequence of gMDH, we generated transgenic Arabidopsis that expressed a chimeric protein consisting of beta-glucuronidase and the N-terminal region of gMDH. Immunological and immunocytochemical studies revealed that the chimeric protein was imported into microbodies such as glyoxysomes and leaf peroxisomes and was then subsequently processed. Site-directed mutagenesis studies showed that the conserved amino acids in the N-terminal presequence, Arg-10 and His-17, function as recognition sites for the targeting to plant microbodies, and Cys-36 in the presequence is responsible for its processing. These results correspond to those from the analyses of glyoxysomal citrate synthase (gCS), which was also synthesized as a large precursor, suggesting that common mechanisms that can recognize the targeting or the processing of gMDH and gCS function in higher plant cells. PMID:9559562

  1. Nutritional and antioxidant profiles of pumpkin (Cucurbita pepo Linn.) immature and mature fruits as influenced by NPK fertilizer.

    PubMed

    Oloyede, F M; Agbaje, G O; Obuotor, E M; Obisesan, I O

    2012-11-15

    This study evaluated the influence of NPK fertilizer on protein, fibre, ash, fat, carbohydrate, antioxidant activities and antioxidant phenolic compounds in immature and mature fruits of pumpkin. The treatment consisted of six NPK levels (0, 50, 100, 150, 200 and 250 kg/ha), and was replicated six times in a randomized complete block design (RCBD). Proximate analysis and antioxidant assays were done using standard analytical methods. At control and lower NPK rates, the proximate compositions and antioxidant profile of pumpkin fruits decreased with increasing NPK fertilizer. Between the control and the highest fertilizer rate, proximate compositions decreased by 7-62% while the antioxidant profile decreased by 13-79% for both immature and mature fruits. Across all the measured parameters, mature fruit had higher proximate contents and higher antioxidant concentrations. For the high health value of pumpkin fruits to be maintained, little or no NPK fertilizer should be applied. PMID:22868114

  2. Tannic acid alleviates bulk and nanoparticle Nd2O3 toxicity in pumpkin: a physiological and molecular response.

    PubMed

    Chen, Guangcai; Ma, Chuanxin; Mukherjee, Arnab; Musante, Craig; Zhang, Jianfeng; White, Jason C; Dhankher, Om Parkash; Xing, Baoshan

    2016-11-01

    The effect of dissolved organic matter (DOM) on nanoparticle toxicity to plants is poorly understood. In this study, tannic acid (TA) was selected as a DOM surrogate to explore the mechanisms of neodymium oxide NPs (Nd2O3 NPs) phytotoxicity to pumpkin (Cucurbita maxima). The results from the tested concentrations showed that 100 mg L(-1) Nd2O3 NPs were significantly toxic to pumpkin in term of fresh biomass, and the similar results from the bulk particles and the ionic treatments were also evident. Exposure to 100 mg L(-1) of Nd2O3 NPs and BPs in 1/5 strength Hoagland's solution not only significantly inhibited pumpkin growth, but also decreased the S, Ca, K and Mg levels in plant tissues. However, 60 mg L(-1) TA significantly moderated the observed phytotoxicity, decreased Nd accumulation in the roots, and notably restored S, Ca, K and Mg levels in NPs and BPs treated pumpkin. TA at 60 mg L(-1) increased superoxide dismutase (SOD) activity in both roots (17.5%) and leaves (42.9%), and catalase (CAT) activity (243.1%) in the roots exposed to Nd2O3 NPs. This finding was confirmed by the observed up-regulation of transcript levels of SOD and CAT in Nd2O3 NPs treated pumpkin analyzed by quantitative reverse transcription polymerase chain reaction. These results suggest that TA alleviates Nd2O3 BPs/NPs toxicity through alteration of the particle surface charge, thus reducing the contact and uptake of NPs by pumpkin. In addition, TA promotes antioxidant enzymatic activity by elevating the transcript levels of genes involved in ROS scavenging. Our results shed light on the mechanisms underlying the influence of DOM on the bioavailability and toxicity of NPs to terrestrial plants. PMID:27308847

  3. Experimental investigation of undesired stable equilibria in pumpkin shape super-pressure balloon designs

    NASA Astrophysics Data System (ADS)

    Schur, W.

    The scientific community's desire for large capacity, constant altitude, long duration stratospheric platforms is not likely going to be met by un-reinforced spherical super-pressure balloons. More likely, the pneumatic envelope for the large-scale super-pressure balloon of the future will be a tendon reinforced structure in which the tendons perform the primary pressure load confining function and the skin serves as a gas barrier and transfers the local pressure load to the tendons. NASA's Ultra Long Duration Balloon (ULDB), which is currently under development, is of that type. By separating the load carrying function of the tendons and the skin a number of advantages are gained. Perhaps most important is the fact that the required skin strength remains to first order independent of the balloon size. Only the size and number of tendons are dictated by the balloon size. By designing the balloon to be at least quasi statically determinate, the stress distributions are more certain, and stress raisers due to fabrication imperfections are more easily controlled and it becomes unnecessary to account for load path uncertainties by providing everywhere excessive strength and structural weight. Furthermore, it becomes possible to use for the envelope skin a visco-elastic film (polyethylene) that has proven performance in the stratospheric environment. The silhouette shape of this balloon type has prompted early researchers to name this design a "pumpkin" shape balloon. Later investigators accepted this terminology. The pumpkin shape balloon concept was adopted by NASA for its ULDB design at the end of 1998 when advantages of that design over a spherical shape design were convincingly demonstrated. Two stratospheric test flights of large-scale super-pressure balloons demonstrated the functioning of this balloon type. In the second successful flight the switch was made from an excessively strong and heavy skin, a holdover from the earlier concept of a spherical design, to

  4. Extraction, isolation and characterisation of oil bodies from pumpkin seeds for therapeutic use.

    PubMed

    Adams, Gary G; Imran, Shahwar; Wang, Sheng; Mohammad, Abubaker; Kok, M Samil; Gray, David A; Channell, Guy A; Harding, Stephen E

    2012-10-15

    Pumpkin, a member of the Cucurbitaceae family has been used frequently as functional medicines for therapeutic use. Several phytochemicals such as polysaccharides, phenolic glycosides, 13-hydroxy-9Z, 11E-octadecatrienoic acid from the leaves of pumpkin, proteins from germinated seeds, have been isolated. Here the influence of pH, ionic strength, and temperature on the properties and stability of oil bodies from pumpkin (Cucurbita) were determined with a view to patterning oil body size and structure for future therapeutic intervention. Oil bodies from pumpkin seeds were extracted, isolated, characterised using optical microscopy, zeta potential and particle size distribution obtained. During microscopic analysis, the oil bodies were more intact and in an integrated form at the time of extraction but were ruptured with time. Water extracted oil bodies were spherical for all four layers where cream had larger oil bodies then upper curd. Lower curd and supernatant had considerably smaller size with lower curd densely packed and seemed to be rich in oil bodies than any of the four layers. At pH 3, in the absence of salt, the zeta potential is approximately +30 mV, but as the salt concentration increases, the ζ potential rises at 10 mM but then decreases over the salt range. This trend continues for the upper curd, lower curd and the supernatant and the degree of the reduction (mV) in zeta potential is of the order cream

  5. Static and quasi-static analysis of lobed-pumpkin balloon

    NASA Astrophysics Data System (ADS)

    Nakashino, Kyoichi; Sasaki, Makoto; Hashimoto, Satoshi; Saito, Yoshitaka; Izutsu, Naoki

    The present study is motivated by the need to improve design methodology for super pressure balloon with 3D gore design concept, currently being developed at the Scientific Balloon Center of ISAS/JAXA. The distinctive feature of the 3-D gore design is that the balloon film has excess materials not only in the circumferential direction but also in the meridional direction; the meridional excess is gained by attaching the film boundaries to the corresponding tendons of a shorter length with a controlled shortening rate. The resulting balloon shape is a pumpkin-like shape with large bulges formed between adjacent tendons. The balloon film, when fully inflated, develops wrinkles in the circumferential direction over its entire region, so that the stresses in the film are limited to a small amount of uniaxial tension in the circumferential direction while the high meridional loads are carried by re-enforced tendons. Naturally, the amount of wrinkling in the film is dominated by the shortening rate between the film boundaries and the tendon curve. In the 3-D gore design, as a consequence, the shortening rate becomes a fundamental design parameter along with the geometric parameters of the gore. In view of this, we have carried out a series of numerical study of the lobed-pumpkin balloon with varying gore geometry as well as with varying shortening rate. The numerical simula-tions were carried out with a nonlinear finite element code incorporating the wrinkling effect. Numerical results show that there is a threshold value for the shortening rate beyond which the stresses in the balloon film increases disproportionately. We have also carried out quasi-static simulations of the inflation process of the lobed-pumpkin balloon, and have obtained asymmetric deformations when the balloon films are in uniaxial tension state.

  6. Uptake, translocation, and accumulation of manufactured iron oxide nanoparticles by pumpkin plants.

    PubMed

    Zhu, Hao; Han, Jie; Xiao, John Q; Jin, Yan

    2008-06-01

    Rapid development and application of nanomaterials and nanotechnology make assessment of their potential health and environmental impacts on humans, non-human biota, and ecosystems imperative. Here we show that pumpkin plants (Cucurbita maxima), grown in an aqueous medium containing magnetite (Fe3O4) nanoparticles, can absorb, translocate, and accumulate the particles in the plant tissues. These results suggest that plants, as an important component of the environmental and ecological systems, need to be included when evaluating the overall fate, transport and exposure pathways of nanoparticles in the environment. PMID:18528537

  7. Molecular Characterization of Tomato leaf curl Palampur virus and Pepper leaf curl betasatellite Naturally Infecting Pumpkin (Cucurbita moschata) in India.

    PubMed

    Namrata, Jaiswal; Saritha, R K; Datta, D; Singh, M; Dubey, R S; Rai, A B; Rai, M

    2010-10-01

    Pumpkin cultivation in India is affected by severe incidence of a yellow vein mosaic disease. Tomato leaf curl New Delhi virus and Squash leaf curl China virus are known to be associated with this disease in India. We were able to identify a third begomovirus-Tomato leaf curl Palampur virus (ToLCPMV), from pumpkin showing typical symptoms of the disease at Varanasi based on the sequence of complete DNA-A genome of the virus. The complete DNA-A sequence of the virus shared more than 99% sequence identity with other ToLCPMV isolates available in the GenBank and clustered with them in the phylogenetic analysis. This betasatellite amplified from the same infected sample has been identified as Pepper leaf curl betasatellite (PepLCB) which also infects chilli in India. There was 92% sequence identity between the two isolates. This is the first report of natural infection of ToLCPMV on pumpkin and association of PepLCB with yellow vein mosaic disease of pumpkin in India. PMID:23637491

  8. An analysis of the deployment of a pumpkin balloon at Mars

    NASA Astrophysics Data System (ADS)

    Rand, J. L.; Phillips, M. L.

    2004-01-01

    The design of large superpressure balloons has received significant attention in recent years due to the successful demonstration of various enabling technologies and materials. Of particular note is the "pumpkin" shaped balloon concept, which allows the stress in the envelope to be limited by the surface geometry. Unlike a sphere, where the radius used to determine the stress is determined by the volume of the balloon, the pumpkin utilizes a system of meridional tendons to react the loading in one direction, and form a number of lobes, which limit the stress in the circumferential direction. A suitable superpressure balloon has been designed using this technology which will carry 2 kg in the atmosphere of Mars. The deployment of this balloon is assumed to occur while falling on a decelerator suitably designed for the Mars atmosphere. The inflation is accomplished by a 10 kg system suspended at the nadir of the balloon. As the system falls toward the surface of the planet, helium gas is transferred into the balloon, forming a partially inflated system very similar to an ascending zero pressure balloon. This analysis incorporates the flow of the planetary gas around the inflating balloon which alters the pressure distribution and shape. As a result, stresses are seen to increase beyond the design values which will require the balloon to be redesigned to accommodate this type of dynamic deployment.

  9. [Preclinical studies of cucurbita maxima (pumpkin seeds) a traditional intestinal antiparasitic in rural urban areas].

    PubMed

    Díaz Obregón, Daysi; Lloja Lozano, Luis; Carbajal Zúñiga, Victor

    2004-01-01

    Experimental research was carried out at the Parasitology and Chemistry laboratories of the Jorge Basadre Grohmann National University, in Tacna. The process involved two phases: (1) determination of the minimum inhibitory concentration (MIC) of Cucurbita Maxima as an antiparasitic agent using canine tapeworms with an intestinal isolation of 5 to 6 hours, and (2) determination of the side-effects of Curbita Maxima on exposed albino rats. It was found that the MIC of 23 gr. of pumpkin seed in 100 ml. of distilled water can produce an antihelminthic effect. This concentration is equivalent to +/- 73 pumpkin seeds (x2 = 5.6, p<0.01). Macroscopically, alterations in helminthic motility are present at a dose of > 23 gr. There is a protheolithic effect with an average survival time of 38.4 minutes. Microscopically the mature proglottids present a destruction of the tegument involving the basal membrane. In the gravid proglottids there is egg destruction. These findings are accentuated when experimenting with Cucurbita Maxima in a concentration of 30 and 32 gr. Superficial non-erosive gastritis was found in weys rats after 4 hours of administering 9 gr/kg. PMID:15614300

  10. Oil and tocopherol content and composition of pumpkin seed oil in 12 cultivars.

    PubMed

    Stevenson, David G; Eller, Fred J; Wang, Liping; Jane, Jay-Lin; Wang, Tong; Inglett, George E

    2007-05-16

    Twelve pumpkin cultivars (Cucurbita maxima D.), cultivated in Iowa, were studied for their seed oil content, fatty acid composition, and tocopherol content. Oil content ranged from 10.9 to 30.9%. Total unsaturated fatty acid content ranged from 73.1 to 80.5%. The predominant fatty acids present were linoleic, oleic, palmitic, and stearic. Significant differences were observed among the cultivars for stearic, oleic, linoleic, and gadoleic acid content of oil. Low linolenic acid levels were observed (<1%). The tocopherol content of the oils ranged from 27.1 to 75.1 microg/g of oil for alpha-tocopherol, from 74.9 to 492.8 microg/g for gamma-tocopherol, and from 35.3 to 1109.7 microg/g for delta-tocopherol. The study showed potential for pumpkin seed oil from all 12 cultivars to have high oxidative stability that would be suitable for food and industrial applications, as well as high unsaturation and tocopherol content that could potentially improve the nutrition of human diets. PMID:17439238

  11. [The fatty acid composition of large pumpkin seed oil (Curucbitae maxima Dich) cultivated in Georgia].

    PubMed

    2014-09-01

    The aim of the study was to identify qualitatively and quantitatively fatty acid composition of large pumpkin seed oil cultivated in Georgia (Cucurbitae maxima Duch) and evaluate its biological activities. Evaluation was conducted using high-performance liquid chromatography method. Fatty acids ranging from C12:0 to C22:0 were identified in the probe. The oil contained 0,2В±0,01mg% lauric, 0,3В±0,01 mg% miristic, 9,0В±0,7mg% palmitic, 5,5В±0,4 mg% stearic, 28,1В±1,0 mg% oleic, 40,2В±1,9 mg% linolic, 12,1В±1,0 mg% linolenic, 2,0В±0,2mg% arachinic and 1,2В±0,1 mg% begenic acids. The investigation showed that large pumpkin seed oil contains a range of biologically significant fatty acids, unique proportion of which attaches great value to the vegetative material. PMID:25341255

  12. Chemometrical classification of pumpkin seed oils using UV-Vis, NIR and FTIR spectra.

    PubMed

    Lankmayr, Ernst; Mocak, Jan; Serdt, Katja; Balla, Branko; Wenzl, Thomas; Bandoniene, Donata; Gfrerer, Marion; Wagner, Siegfried

    2004-10-29

    The main outcome of this work is elaboration of classification models for edible oil samples representing the most widespread brands of Austrian pumpkin seed oil. A complete spectral characterisation of the pumpkin seed oil samples by UV-Vis, NIR and FTIR spectra was obtained together with their basic sensorial classification. Chemometrical processing of the measured data enabled the detection of the most important spectral features, which are crucial for categorising the oils into two or three classes according to their sensory quality evaluated by a panel of experts. The elaborated models thus make it possible to predict the category into which a hitherto unclassified oil sample belongs--considering classification into either two categories, containing oils with overall acceptable scores or oils that were not accepted, or three categories, involving oils fulfilling all quality criteria, oils with good scores and not accepted oils. This will perspectively facilitate the determination of chemical substances responsible for bad taste, odour and colour of the respective oil brands, as well as finding substances contributing to the excellent sensorial perception of some tested products. PMID:15560925

  13. Structural diversity of pectins isolated from the Styrian oil-pumpkin (Cucurbita pepo var. styriaca) fruit.

    PubMed

    Košťálová, Zuzana; Hromádková, Zdenka; Ebringerová, Anna

    2013-03-01

    To evaluate the seeded fruit biomass of the Styrian oil-pumpkin in view of its pectin component, a series of acidic polysaccharides were isolated by a six-step sequential extraction using hot water, EDTA, dilute HCl (twice) and dilute and stronger NaOH solutions. Chemical, physicochemical and spectroscopy analyses revealed that the first four fractions comprised partially methyl-esterified and acetylated pectins with varying proportions of rhamnogalacturonan regions ramified with galactose- and arabinose-containing side chains and showed considerable polymolecularity. The alkali-extracted polysaccharides contained lower amounts of pectins with homogalacturonan and arabinose-rich rhamnogalacturonan regions next to hemicelluloses prevailing in the last polysaccharide. Using (1)H-(13)C HSQC and HMBC spectroscopy, the resonances of free and methylesterified galacturonic acid residues in the purified acid-extracted pectin were unambiguously established and various diads formed by both residues identified. The results might serve as a basis for searching technological conditions to produce pectin from the oil-pumpkin fruit biomass. PMID:23465915

  14. Three new triterpene esters from pumpkin (Cucurbita maxima) seeds.

    PubMed

    Kikuchi, Takashi; Ueda, Shinsuke; Kanazawa, Jokaku; Naoe, Hiroki; Yamada, Takeshi; Tanaka, Reiko

    2014-01-01

    Three new multiflorane-type triterpene esters, i.e. 7α-hydroxymultiflor-8-ene-3α,29-diol 3-acetate-29-benzoate (1), 7α-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (2), and 7β-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (3), were isolated from seeds of Cucurbita maxima, along with the known compound, multiflora-7,9(11)-diene-3α,29-diol 3,29-dibenzoate (4). Compound 1 exhibited melanogenesis inhibitory activities comparable with those of arbutin. In cytotoxicity assays, compounds 1 and 3 exhibited weak cytotoxicity, with IC50 values of 34.5-93.7 μM against HL-60 and P388 cells. PMID:24743937

  15. Enhanced Production of Phenolic Compounds from Pumpkin Leaves by Subcritical Water Hydrolysis

    PubMed Central

    Ko, Jeong-Yeon; Ko, Mi-Ok; Kim, Dong-Shin; Lim, Sang-Bin

    2016-01-01

    Enhanced production of individual phenolic compounds by subcritical water hydrolysis (SWH) of pumpkin leaves was investigated at various temperatures ranging from 100 to 220°C at 20 min and at various reaction times ranging from 10 to 50 min at 160°C. Caffeic acid, p-coumaric acid, ferulic acid, and gentisic acid were the major phenolic compounds in the hydrolysate of pumpkin leaves. All phenolic compounds except gentisic acid showed the highest yield at 160°C, but gentisic acid showed the highest yield at 180°C. The cumulative amount of individual phenolic compounds gradually increased by 48.1, 52.2, and 78.4 μg/g dry matter at 100°C, 120°C, and 140°C, respectively, and then greatly increased by 1,477.1 μg/g dry matter at 160°C. The yields of caffeic acid and ferulic acid showed peaks at 20 min, while those of cinnamic acid, p-coumaric acid, p-hydroxybenzoic acid, and procatechuic acid showed peaks at 30 min. Antioxidant activities such as 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power values gradually increased with hydrolysis temperature and ranged from 6.77 to 12.42 mg ascorbic acid equivalents/g dry matter and from 4.25 to 8.92 mmol Fe2+/100 g dry matter, respectively. Color L* and b* values gradually decreased as hydrolysis temperature increased from 100°C to 140°C. At high temperatures (160°C to 220°C), L* and b* values decreased suddenly. The a* value peaked at 160°C and then decreased as temperature increased from 160°C to 220°C. These results suggest that SWH of pumpkin leaves was strongly influenced by hydrolysis temperature and may enhanced the production of phenolic compounds and antioxidant activities. PMID:27390730

  16. Enhanced Production of Phenolic Compounds from Pumpkin Leaves by Subcritical Water Hydrolysis.

    PubMed

    Ko, Jeong-Yeon; Ko, Mi-Ok; Kim, Dong-Shin; Lim, Sang-Bin

    2016-06-01

    Enhanced production of individual phenolic compounds by subcritical water hydrolysis (SWH) of pumpkin leaves was investigated at various temperatures ranging from 100 to 220°C at 20 min and at various reaction times ranging from 10 to 50 min at 160°C. Caffeic acid, p-coumaric acid, ferulic acid, and gentisic acid were the major phenolic compounds in the hydrolysate of pumpkin leaves. All phenolic compounds except gentisic acid showed the highest yield at 160°C, but gentisic acid showed the highest yield at 180°C. The cumulative amount of individual phenolic compounds gradually increased by 48.1, 52.2, and 78.4 μg/g dry matter at 100°C, 120°C, and 140°C, respectively, and then greatly increased by 1,477.1 μg/g dry matter at 160°C. The yields of caffeic acid and ferulic acid showed peaks at 20 min, while those of cinnamic acid, p-coumaric acid, p-hydroxybenzoic acid, and procatechuic acid showed peaks at 30 min. Antioxidant activities such as 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power values gradually increased with hydrolysis temperature and ranged from 6.77 to 12.42 mg ascorbic acid equivalents/g dry matter and from 4.25 to 8.92 mmol Fe(2+)/100 g dry matter, respectively. Color L* and b* values gradually decreased as hydrolysis temperature increased from 100°C to 140°C. At high temperatures (160°C to 220°C), L* and b* values decreased suddenly. The a* value peaked at 160°C and then decreased as temperature increased from 160°C to 220°C. These results suggest that SWH of pumpkin leaves was strongly influenced by hydrolysis temperature and may enhanced the production of phenolic compounds and antioxidant activities. PMID:27390730

  17. Velocity Ellipsoids for Crustal Seismic Anisotropy: Pumpkins and Melons Have Dimples and Bulges

    NASA Astrophysics Data System (ADS)

    Okaya, D.; Christensen, N.

    2003-12-01

    Geological causes of crustal anisotropy include regional fractures and cracks, isotropic heterogeneity or layering, and material composition and textural properties. In addition, shear or metamorphic foliations in fault zones or structural terranes serve as proxies for intracrustal deformation in a manner analogous to lattice preferred orientation of olivine produced by mantle shear. The primary factor in the production of crustal seismic anisotropy is the relative angle between a seismic wave and the (dipping) symmetry axes representing the crustal material even as either change along the propagation raypath. As a result, in order to analyze observations of crustal anisotropy we must understand the behavior of compressional and shear wave velocities in all propagation directions parallel to and in-between the principal symmetry axes which represent the crustal materials. In this poster we use Christoffel equations and physical properties obtained from petrophysical lab measurements in order to examine anisotropic velocities and travel-time effects for bulk rocks representative of different crustal levels. Ellipses and ellipsoids are commonly used to represent the P- and S-wave velocity directional behavior for materials described using hexagonal and orthorhombic symmetries, respectively. While olivine and pyroxene-based mantle rocks are characteristically fast symmetry axes (the "melons" of Levin and Park, 1997), crustal rocks are typically slow symmetry axes ("pumpkins") due to the predominance of fractures or textural foliations. Careful application of Christoffel solutions indicate that for most crustal (and mantle) rocks the surfaces of their pumpkins or melons are not exact analytical ellipsoids. Rather, the surfaces in the non-axial directions have second-order deflections (bulges or dimples) which potentially may produce observable azimuthal travel-time or shear splitting effects. In the case when the P-wave surface on average is slow (dimpled), due to SV

  18. Protective effect of pumpkin seed extract on sperm characteristics, biochemical parameters and epididymal histology in adult male rats treated with cyclophosphamide.

    PubMed

    Aghaei, S; Nikzad, H; Taghizadeh, M; Tameh, A A; Taherian, A; Moravveji, A

    2014-10-01

    Cancer treatment with cyclophosphamide (CP) may result in reproductive toxicity as one of its side effects. The pumpkin seed is a rich natural source of antioxidant. We have assessed the possible protective efficacy of pumpkin seed extract on sperm characteristics, biochemical parameters and epididymal histology of CP-treated rats. Male adult Wistar rats were categorised into four groups. Group 1 served as control and received intraperitoneal (IP) injection of isotonic saline solution. Group 2 rats were treated with CP by IP injection in a single dose of 100 mg/kg body weight, only once. Group 3 and 4 received CP plus 300 and 600 mg/kg pumpkin seed extract respectively. Six weeks after treatment, sperm characteristics, biochemical parameters and histopathological changes were examined. Results showed that, sperm characteristics in CP-treated rats were significantly decreased. Biochemical analysis results showed that the co-administration of 300 mg pumpkin seed extract could increase the total antioxidant capacity (TAC) level significantly. In CP-treated rats, histopathological changes such as vacuolisation, disorganisation and separation of epididymal epithelium were observed as well. Interestingly, pumpkin seed extract could improve the above-mentioned parameters remarkably in CP-treated rats. Our findings indicated that pumpkin seed extract might be used as protective agent against CP-induced reproductive toxicity. PMID:24124763

  19. Complete genome sequence of a new bipartite begomovirus infecting fluted pumpkin (Telfairia occidentalis) plants in Cameroon.

    PubMed

    Leke, Walter N; Khatabi, Behnam; Fondong, Vincent N; Brown, Judith K

    2016-08-01

    The complete genome sequence was determined and characterized for a previously unreported bipartite begomovirus from fluted pumpkin (Telfairia occidentalis, family Cucurbitaceae) plants displaying mosaic symptoms in Cameroon. The DNA-A and DNA-B components were ~2.7 kb and ~2.6 kb in size, and the arrangement of viral coding regions on the genomic components was like those characteristic of other known bipartite begomoviruses originating in the Old World. While the DNA-A component was more closely related to that of chayote yellow mosaic virus (ChaYMV), at 78 %, the DNA-B component was more closely related to that of soybean chlorotic blotch virus (SbCBV), at 64 %. This newly discovered bipartite Old World virus is herein named telfairia mosaic virus (TelMV). PMID:27262944

  20. Adsorption of transition metals in aqueous solutions by fluted pumpkin (Telfairia occidentalis Hook f) waste.

    PubMed

    Horsfall, Michael; Spiff, Ayebaemi Ibuteme

    2005-09-01

    The adsorption of some divalent transition metal (Hg, Rh, Pt, and Pd) ions in aqueous solution onto fluted pumpkin waste biomass has been investigated. The data were discussed in terms of ionic radii, surface area, and the hard-soft acid-base (HSAB) concept. The monolayer sorption capacities as obtained by the Langmuir adsorption isotherm model were determined to be ca. 9.89 mg/g, 9.81 mg/g, 10.59 mg/g, and 6.84 mg/g for for Hg(II), Rh(II), Pt(II), and Pd(II), respectively. The results are relevant for the optimal design of a wastewater treatment plant and for prediction of model parameters of sorbate-sorbent interactions. PMID:17193209

  1. The complete mitochondrial genome of the pumpkin fruit fly, Bactrocera tau (Diptera: Tephritidae).

    PubMed

    Tan, Meihua; Zhang, Rui; Xiang, Caiyu; Zhou, Xin

    2016-07-01

    The pumpkin fruit fly, Bactrocera tau, is an important quarantine pest in many countries because of its mass destructiveness to a variety of vegetable and fruit plants. In this study, we report the complete mitochondrial genome (mitogenome) of B. tau. Its complete mitogenome sequence is 15,687 bp in length, which contains a non-coding control region and all of the 37 genes of bilaterian animals (13 protein-coding genes, 22 tRNA genes and 2 rRNA genes). A phylogenetic tree of the complete mitogenome of all available Tephritidae species was established to approve the accuracy. The base composition of mitogenome sequence and the gene arrangement including directions are rather conservative, compared to other published mitogenomes of Bactrocera species. This first complete mitogenome of B. tau will facilitate the development of new DNA markers for species diagnosis, therefore improving accurate detection of quarantine species. PMID:26024140

  2. Inhibition Effects of Silver Nanoparticles against Powdery Mildews on Cucumber and Pumpkin.

    PubMed

    Lamsal, Kabir; Kim, Sang-Woo; Jung, Jin Hee; Kim, Yun Seok; Kim, Kyoung Su; Lee, Youn Su

    2011-03-01

    Powdery mildew is one of the most devastating diseases in cucurbits. Crop yield can decline as the disease severity increases. In this study, we evaluated the effect of silver nanoparticles against powdery mildew under different cultivation conditions in vitro and in vivo . Silver nanoparticles (WA-CV-WA13B) at various concentrations were applied before and after disease outbreak in plants to determine antifungal activities. In the field tests, the application of 100 ppm silver nanoparticles showed the highest inhibition rate for both before and after the outbreak of disease on cucumbers and pumpkins. Also, the application of 100 ppm silver nanoparticles showed maximum inhibition for the growth of fungal hyphae and conidial germination in in vivo tests. Scanning electron microscope results indicated that the silver nanoparticles caused detrimental effects on both mycelial growth and conidial germination. PMID:22783069

  3. The design process for a pumpkin balloon: structural synthesis, structural analysis, and analytical assessment of some critical design issues

    NASA Astrophysics Data System (ADS)

    Schur, W. W.

    Effects of varying parameters in the design of super-pressure balloons of the "pumpkin" shape such as gore design, tendon stiffness, and structural lack-of-fit between tendons and gore seams are exhibited in analytical studies. The importance of an accurate representation of Poisson's effect for the film is demonstrated. Important design aspects that affect load paths and robustness of the design are discussed together with their resolution and quantification where applicable.

  4. Characterization of the aroma signature of styrian pumpkin seed oil ( Cucurbita pepo subsp. pepo var. Styriaca) by molecular sensory science.

    PubMed

    Poehlmann, Susan; Schieberle, Peter

    2013-03-27

    Application of the aroma extract dilution analysis on a distillate prepared from an authentic Styrian pumpkin seed oil followed by identification experiments led to the characterization of 47 odor-active compounds in the flavor dilution (FD) factor range of 8-8192 among which 2-acetyl-1-pyrroline (roasty, popcorn-like), 2-propionyl-1-pyrroline (roasty, popcorn-like), 2-methoxy-4-vinylphenol (clove-like), and phenylacetaldehyde (honey-like) showed the highest FD factors. Among the set of key odorants, 2-propionyl-1-pyrroline and another 20 odorants were identified for the first time as constituents of pumpkin seed oil. To evaluate the aroma contribution in more detail, 31 aroma compounds showing the highest FD factors were quantitated by means of stable isotope dilution assays. On the basis of the quantitative data and odor thresholds determined in sunflower oil, odor activity values (OAV; ratio of concentration to odor threshold) were calculated, and 26 aroma compounds were found to have an OAV above 1. Among them, methanethiol (sulfury), 2-methylbutanal (malty), 3-methylbutanal (malty), and 2,3-diethyl-5-methylpyrazine (roasted potato) reached the highest OAVs. Sensory evaluation of an aroma recombinate prepared by mixing the 31 key odorants in the concentrations as determined in the oil revealed that the aroma of Styrian pumpkin seed oil could be closely mimicked. Quantitation of 11 key odorants in three commercial pumpkin seed oil revealed clear differences in the concentrations of distinct odorants, which were correlated with the overall aroma profile of the oils. PMID:23461409

  5. Effects of pumpkin seed oil and saw palmetto oil in Korean men with symptomatic benign prostatic hyperplasia.

    PubMed

    Hong, Heeok; Kim, Chun-Soo; Maeng, Sungho

    2009-01-01

    This study was to investigate the role of complementary and alternative medicine in the prevention and treatment of benign prostatic hyperplasia. For this purpose, a randomized, double-blind, placebo-controlled trial was performed over 12 months on 47 benign prostatic hyperplasia patients with average age of 53.3 years and international prostate symptom score over 8. Subjects received either sweet potato starch (group A, placebo, 320 mg/day), pumpkin seed oil (group B, 320 mg/day), saw palmetto oil (group C, 320 mg/day) or pumpkin seed oil plus saw palmetto oil (group D, each 320 mg/day). International prostate symptom score, quality of life, serum prostate specific antigen, prostate volume and maximal urinary flow rate were measured. In groups B, C and D, the international prostate symptom score were reduced by 3 months. Quality of life score was improved after 6 months in group D, while those of groups B and C were improved after 3 months, compared to the baseline value. Serum prostate specific antigen was reduced only in group D after 3 months, but no difference was observed in prostate volume in all treatment groups. Maximal urinary flow rate were gradually improved in groups B and C, with statistical significance after 6 months in group B and after 12 months in group C. None of the parameters were significantly improved by combined treatment with pumpkin seed oil and saw palmetto oil. From these results, it is suggested that administrations of pumpkin seed oil and saw palmetto oil are clinically safe and may be effective as complementary and alternative medicine treatments for benign prostatic hyperplasia. PMID:20098586

  6. Microwave-assisted aqueous enzymatic extraction of oil from pumpkin seeds and evaluation of its physicochemical properties, fatty acid compositions and antioxidant activities.

    PubMed

    Jiao, Jiao; Li, Zhu-Gang; Gai, Qing-Yan; Li, Xiao-Juan; Wei, Fu-Yao; Fu, Yu-Jie; Ma, Wei

    2014-03-15

    Microwave-assisted aqueous enzymatic extraction (MAAEE) of pumpkin seed oil was performed in this study. An enzyme cocktail comprised of cellulase, pectinase and proteinase (w/w/w) was found to be the most effective in releasing oils. The highest oil recovery of 64.17% was achieved under optimal conditions of enzyme concentration (1.4%, w/w), temperature (44°C), time (66 min) and irradiation power (419W). Moreover, there were no significant variations in physicochemical properties of MAAEE-extracted oil (MAAEEO) and Soxhlet-extracted oil (SEO), but MAAEEO exhibited better oxidation stability. Additionally, MAAEEO had a higher content of linoleic acid (57.33%) than SEO (53.72%), and it showed stronger antioxidant activities with the IC50 values 123.93 and 152.84, mg/mL, according to DPPH radical scavenging assay and β-carotene/linoleic acid bleaching test. SEM results illustrated the destruction of cell walls and membranes by MAAEE. MAAEE is, therefore, a promising and environmental-friendly technique for oil extraction in the food industry. PMID:24206680

  7. Anthelmintic efficacy of pumpkin seed (Cucurbita pepo Linnaeus, 1753) on ostrich gastrointestinal nematodes in a semiarid region of Paraíba State, Brazil.

    PubMed

    Feitosa, Thais Ferreira; Vilela, Vinícius Longo Ribeiro; Athayde, Ana Célia Rodrigues; Braga, Fábio Ribeiro; Dantas, Elaine Silva; Vieira, Vanessa Diniz; de Melo, Lídio Ricardo Bezerra

    2013-01-01

    The aim of this study was to verify the in vivo effectiveness of pumpkin seed (Curcubita pepo Linnaeus, 1753) in naturally infected ostriches in the Cariri zone, semiarid region of Paraíba State, Brazil. Forty-eight ostriches were used, African Black breed, of 14 to 36 months old, naturally infected by gastrointestinal nematodes. These animals were divided into four groups of 12 ostriches. Group 1 consists of animals treated with 0.5 g/kg live weight (l. w.) of pumpkin seed meal; group 2 received 1 g/kg l. w. of pumpkin seed meal; group 3 was treated with Albendazole 5 %, at the dosage of 1 mL/10 kg l. w.; and Group 4 was the control group and do not received treatment. Groups 1 and 2 received the treatment for three consecutive days, orally, at intervals of 7 days, totaling nine administrations. The Albendazole 5 % was administered one time, at the beginning of the experiment, according to the manufacturer's recommendations. The groups treated with pumpkin seed showed a significant decrease in egg counts per gram of feces (EPG), wherein group 2 (1 g/kg l. w.) was the most effective. The control and drug groups showed no reduction in EPG. The results of the present study demonstrate that the administration of pumpkin seed was effective in controlling gastrointestinal helminths in naturally infected ostriches. PMID:22684690

  8. An analysis of the deployment of a pumpkin balloon on mars

    NASA Astrophysics Data System (ADS)

    Rand, J.; Phillips, M.

    The design of large superpressure balloons has received significant attention in recent years due to the successful demonstration of various enabling technologies and materials. Of particular note is the "pumpkin" shaped balloon concept, which allows the stress in the envelope to be limited by the surface geometry. Unlike a sphere, which produces stress resultants determined by the volume of the system, the pumpkin utilizes a system of meridional tendons to react the loading in one direction, and form a number of lobes, which limit the stress in the circumferential direction. The application of this technology to very large systems is currently being demonstrated by NASA's Ultra Long Duration Balloon (ULDB) Program. However, this type of balloon has certain features that may be exploited to produce a system far more robust than a comparable sphere during deployment, inflation, and operation for long periods of time. When this concept is applied to a system designed to carry two kilograms in the atmosphere of Mars, the resulting balloon is small enough to alter the construction techniques and produce an envelope which is free of tucks and folds which may cause uncontrolled stress concentrations. A technique has been demonstrated where high strength tendons may be pretensioned prior to installation along the centerline of each gore. Since this position is the shortest distance between the apex and nadir of the balloon, the tendons will automatically resist the forces caused by deployment and inflation and thereby protect the thin film gas barrier from damage. A suitable balloon has been designed for this type of mission using five-micron Mylar Type C film for the gas barrier and P O braided cables for the meridionalB load carrying members. The deployment of this balloon is assumed to occur while falling on a decelerator suitably designed for the Mars atmosphere. The inflation is accomplished by a ten-kilogram system suspended at the nadir of the balloon. As the

  9. Special Considerations for Qualifying Thin Films for Supper Pressure Pumpkin Ultra Long Duration Balloon (ULDB) Missions

    NASA Astrophysics Data System (ADS)

    Said, M.

    Pumpkin type super pressure balloons require much less stringent mechanical requirements on the envelope film material when compared to spherical super pressure type balloons. However, since suitable thin films are typically viscoelastic in nature, their creep characteristics must be fully characterized and must not exceed specific and predetermined design limits. Proper assessment of materials limits to meet these design limits requires creep-load-temperature data that characterizes the performance of the material over a time that exceeds the duration of the design service life by some specified margin. Contrary to the behavior of materials with purely elastic response, visco-elastic materials such as these considered for the ULDB design, change their geometry under sustained loading over time. This change is usually reflected by exhibiting a significant visco-elastic component over the service life of the mission. For that regime of large visco-elastic response, where the material is highly nonlinear, a certain load-temperature threshold can be reached where the creep is limited by an asymptote that depends on both the temperature and load level. Such creep is recoverable, although the recovery period may be much longer than the 100 day design service life of the ULDB structure plus the factor of safety required for the design. For a typical flight, the most significant creep occurs at the highest temperature, which also produces the highest internal pressure. At mid- latitudes a significant portion of the service life is spent at night, i.e. at low temperature and low load; for the ULDB film, this nighttime contribution to creep is insignificant in comparison to any daytime contribution. By contrast, flight exposure in an Antarctic summer is at an almost constant high temperature and corresponding high pressure. This response behavior must be sufficiently characterized to serve the needs of the structural design and performance predictions of the vehicle in

  10. The hypoglycemic effect of pumpkin seeds, Trigonelline (TRG), Nicotinic acid (NA), and D-Chiro-inositol (DCI) in controlling glycemic levels in diabetes mellitus.

    PubMed

    Adams, Gary G; Imran, Shahwar; Wang, Sheng; Mohammad, Abubaker; Kok, M Samil; Gray, David A; Channell, Guy A; Harding, Stephen E

    2014-01-01

    In the contemporary society, diabetes mellitus is considered as a common, growing, serious, costly, and potentially preventable public health problem. It is forecasted that in 2030, the number of people with diabetes will go up from 117 million in 2000 to 366 million in 2030. The prevalence of diabetes will place a huge burden on health and financial structures of countries, and these will impact on individuals, as well as families and nations. Polysaccharides, para-aminobenzoic acid, fixed oils, sterol, proteins, and peptides are biologically active ingredients, which are found in pumpkins. The chemicals within pumpkins such as the fruit pulp, oil from ungerminated seeds, and protein from germinated seeds have hypoglycemic properties. Preliminary investigation showed that pumpkin seeds, and the macromolecules, therein, such as Trigonelline (TRG), Nicotinic acid (NA), and D-chiro-inositol (DCI), possess hypoglycemic properties and could assist in maintaining glycemic control. PMID:24564589

  11. Non-linear analysis and the design of Pumpkin Balloons: stress, stability and viscoelasticity

    NASA Astrophysics Data System (ADS)

    Rand, J. L.; Wakefield, D. S.

    Tensys have a long-established background in the shape generation and load analysis of architectural stressed membrane structures Founded upon their inTENS finite element analysis suite these activities have broadened to encompass lighter than air structures such as aerostats hybrid air-vehicles and stratospheric balloons Winzen Engineering couple many years of practical balloon design and fabrication experience with both academic and practical knowledge of the characterisation of the non-linear viscoelastic response of the polymeric films typically used for high-altitude scientific balloons Both companies have provided consulting services to the NASA Ultra Long Duration Balloon ULDB Program Early implementations of pumpkin balloons have shown problems of geometric instability characterised by improper deployment and these difficulties have been reproduced numerically using inTENS The solution lies in both the shapes of the membrane lobes and also the need to generate a biaxial stress field in order to mobilise in-plane shear stiffness Balloons undergo significant temperature and pressure variations in flight The different thermal characteristics between tendons and film can lead to significant meridional stress Fabrication tolerances can lead to significant local hoop stress concentrations particularly adjacent to the base and apex end fittings The non-linear viscoelastic response of the envelope film acts positively to help dissipate stress concentrations However creep over time may produce lobe geometry variations that may

  12. Developmental instability: measures of resistance and resilience using pumpkin (Cucurbita pepo L.)

    USGS Publications Warehouse

    Freeman, D. Carl; Brown, Michelle L.; Dobson, Melissa; Jordan, Yolanda; Kizy, Anne; Micallef, Chris; Hancock, Leandria C.; Graham, John H.; Emlen, John M.

    2003-01-01

    Fluctuating asymmetry measures random deviations from bilateral symmetry, and thus estimates developmental instability, the loss of ability by an organism to regulate its development. There have been few rigorous tests of this proposition. Regulation of bilateral symmetry must involve either feedback between the sides or independent regulation toward a symmetric set point. Either kind of regulation should decrease asymmetry over time, but only right–left feedback produces compensatory growth across sides, seen as antipersistent growth following perturbation. Here, we describe the developmental trajectories of perturbed and unperturbed leaves of pumpkin, Cucurbita pepoL., grown at three densities. Covering one side of a leaf with aluminium foil for 24 h perturbed leaf growth. Reduced growth on the perturbed side caused leaves to become more asymmetrical than unperturbed controls. After the treatment the size-corrected asymmetry decreased over time. In addition, rescaled range analysis showed that asymmetry was antipersistent rather than random, i.e. fluctuation in one direction was likely to be followed by fluctuations in the opposite direction. Development involves right–left feedback. This feedback reduced size-corrected asymmetry over time most strongly in the lowest density treatment suggesting that developmental instability results from a lack of resilience rather than resistance. 

  13. Genetic diversity of Phytophthora capsici isolates from pepper and pumpkin in Argentina.

    PubMed

    Gobena, Daniel; Roig, Julián; Galmarini, Claudio; Hulvey, Jon; Lamour, Kurt

    2012-01-01

    Phytophthora capsici is a soilborne oomycete plant pathogen that limits pepper production worldwide. The population structure varies significantly depending on the location (e.g. Peru vs. USA) and little is known about the diversity of P. capsici in Argentina. Our objective was to assess the diversity of P. capsici in Argentina at key pepper production areas. Forty isolates were recovered 2006-2009 from pepper and one isolate from pumpkin at 11 locations. Isolates were assessed for mating type, mefenoxam sensitivity and multilocus single nucleotide polymorphism (SNP) genotype profiles. Ten isolates with identical SNP profiles also were genotyped with amplified fragment length polymorphism (AFLP) markers. All 41 isolates had the A1 mating type and were sensitive to mefenoxam. Genotypic analysis using eight polymorphic SNP markers indicated 87% of the isolates had the same multilocus genotype, which is fixed for heterozygosity at seven of the eight SNP sites. AFLP analyses confirmed these findings, and overall it appears that clonal reproduction drives the population structure of P. capsici in Argentina. The implications for breeding resistant peppers and overall disease management are discussed. PMID:21933926

  14. Predictive modeling of an azo metal complex dye sorption by pumpkin husk.

    PubMed

    Çelekli, Abuzer; Bozkurt, Hüseyin

    2013-10-01

    Effective disposal of pumpkin husk (PH) as a redundant waste is a significant work for environmental protection and full utilization of resource. Predictive modeling of sorption of Lanaset Red (LR) G on PH was investigated in a batch system as functions of particle size, adsorbent dose, pH, temperature, and initial dye concentration. Fourier transform infrared spectroscopy attenuated total reflectance spectra of PH powders before and after the sorption of LR G were determined. Sorption process was found to be dependent on particle size, adsorbent dose, pH, temperature, initial dye concentration, and contact time. Amine and amide groups of PH had significant effect on the sorption process. The pHzpc of PH was found as 6.4. Sorption process was very fast initially and reached equilibrium within 60 min. Dynamic behavior of sorption was well represented by logistic and Avrami models. The sorption of LR G on PH was excellently described by Langmuir model, indicating a homogeneous phenomenon. Monolayer sorption capacity decreased from 440.78 to 436.28 mg g(-1) with increasing temperature. Activation energy, thermodynamic, and desorption studies showed that this process was physical character, exothermic, and spontaneous. This study confirmed that PH as an effective and low-cost adsorbent had a great potential for the removal of LR G as an alternative eco-friendly process. PMID:23625123

  15. An improved method to discover adulteration of Styrian pumpkin seed oil.

    PubMed

    Wenzl, Thomas; Prettner, Elke; Schweiger, Klaus; Wagner, Franz S

    2002-01-01

    Pumpkin seed oil is rather expensive compared to other vegetable oils. Therefore, it is often adulterated by the addition of cheaper oils. In contrast to other edible oils, the content of Delta 5-sterols is very low, while Delta 7-sterols are dominating. The determination of Delta 5-sterols, especially beta-sitosterol has proven to be a good possibility to detect admixture of cheap vegetable oils to a level below which the economic profit is not significant any more. The presented method is a variant of an analysis concept, which has been published previously in European Food Research and Technology by Mandl et al. [Eur. Food Res. Technol. 209 (1999) 400. ]. It includes saponification of the triglycerides as a first step followed by separation of the potassium salts of the fatty acids from the unsaponifiable fraction by adsorption chromatography. In order to enhance gas chromatographic properties of the analytes, the hydroxyl function of the sterols is derivatized with N-Methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) to the trimethylsilylether. Finally, the analytes are separated on a capillary column of medium polarity (HP 35 MS) in a temperature programmed run within 18 min. Detection of the analytes was done by flame ionization. Special attention was set onto the precision and repeatability of the method. PMID:12406602

  16. [Main carotenoids in pressed seeds (Cucurbitae semen) of oil pumpkin (Cucurbita pepo convar. pepo var. styriaca)].

    PubMed

    Matus, Z; Molnár, P; Szabó, L G

    1993-09-01

    Various use of the oil-pumpkin offers reason for the phytochemical analysis of seed-meal's carotene pigments. Column chromatography was performed on the adsorbents MgO, Celite and CaCO3 with hexane and benzene as eluents. HPLC separation of different pigments was carried out on a 6 microns reverse phase packing with a ternary gradient elution method using a diode-array detector. The main components of the press-residue were lutein [3,3'-dihydroxy-alpha-carotene = (3R,3'R,6'R)-beta,epsilon-carotene-3,3'-diol; 52.5%] and beta-carotene (beta,epsilon-carotene; 10.1%). In addition to the above-mentioned pigments it was successful to reveal the presence of violaxanthin, luteoxanthin, auroxanthin epimers, lutein epoxide, flavoxanthin, chrysanthemaxanthin, 9(9')-cis-lutein, 13(13')-cis-lutein, 15-cis-lutein (central-cis)-lutein, alpha-cryptoxanthin, beta-cryptoxanthin and alpha-carotene (beta,epsilon-carotene) in small quantities. PMID:8249609

  17. Efficacy of simvastatin and pumpkin-seed oil in the management of dietary-induced hypercholesterolemia.

    PubMed

    al-Zuhair, H; Abd el-Fattah, A A; Abd el Latif, H A

    1997-05-01

    Pumpkin-seed oil (PSO), a natural supplement rich with antioxidants and polyunsaturated fatty acids (PUFAs), was given in combination with simvastatin, as antihypercholesterolemic drug, to high cholesterol-fed rabbits, for three weeks. In comparison with normal rabbits, a significant increase of the aortic contractile response to norepinephrine was observed which could be attributed to endothelium dysfunction. In addition, serum levels of total lipids, triacylglycerols, total cholesterol and low density lipoprotein-cholesterol (LDL-C) were increased while phospholipids and high density lipoprotein-cholesterol (HDL-C) were decreased in hypercholesterolemic rabbits. These changes could be related to the predominance of LDL and oxidized-LDL particles caused by high levels of reactive oxygen species during hypercholesterolemia (HC). Treatment with simvastatin modulated most of the altered parameters affected during HC that might be, in part, due to inhibition of cholesterol biosynthesis. While concomitant administration of simvastatin and PSO succeeded to cause marked reduction of the aortic contractile response to norepinephrine and to normalize the most adverse effects observed during HC. These effects were explained by the potentiating effects of simvastatin with antioxidants and essential fatty acids in PSO. On the contrary, serum activities of aminotransferases and creatine phosphokinase were increased with simvastatin treatment but not with the combination therapy in hypercholesterolemic rabbits. PMID:9299202

  18. Cytosolic aconitase participates in the glyoxylate cycle in etiolated pumpkin cotyledons.

    PubMed

    Hayashi, M; De Bellis, L; Alpi, A; Nishimura, M

    1995-06-01

    Two different aconitases are known to be expressed after the germination of oil-seed plants. One is a mitochondrial aconitase that is involved in the tricarboxylic acid cycle. The other participates in the glyoxylate cycle, playing a role in gluconeogenesis from stored oil. We isolated and characterized a cDNA for an aconitase from etiolated pumpkin cotyledons. The cDNA was 3,145 bp long and capable of encoding a protein of 98 kDa. N-terminal and C-terminal amino acid sequences deduced from the cDNA did not contain mitochondrial or glyoxysomal targeting signals. A search of protein databases suggested that the cDNA encoded a cytosolic aconitase. Immunoblotting analysis with a specific antibody against the aconitase expressed in Escherichia coli revealed that developmental changes in the amount of the aconitase were correlated with changes in levels of other enzymes of the glyoxylate cycle during growth of seedlings. Further analysis by subcellular fractionation and immunofluorescence microscopy revealed that aconitase was present only the cytosol and mitochondria. No glyoxysomal aconitase was found in etiolated cotyledons even though all the other enzymes of the glyoxylate cycle are known to be localized in glyoxysomes. Taken together, the data suggest that the cytosolic aconitase participates in the glyoxylate cycle with four glyoxysomal enzymes. PMID:7640891

  19. Effect of different drying methods on moisture ratio and rehydration of pumpkin slices.

    PubMed

    Seremet Ceclu, Liliana; Botez, Elisabeta; Nistor, Oana-Viorela; Andronoiu, Doina Georgeta; Mocanu, Gabriel-Danut

    2016-03-15

    This study was carried to determine the influence of hot air drying process and combined methods on physicochemical properties of pumpkin (Cucurbita moschata) samples. The experiments in hot air chamber were lead at 50, 60 and 70 °C. The combined method consists of a triple combination of the main drying techniques. Thus, in first stage the samples were dried in hot air convection at 60 °C followed by hot air ventilation at 40 °C simultaneous with microwave. The time required to reduce the moisture content to any given level was highly dependent on the drying conditions. So, the highest value of drying time in hot air has been 540 min at 50 °C, while the lowest time has been 189 min in hot air combined by microwave at 40 °C and a power of 315 W. The samples dried by hot air shows a higher rehydration capacity than samples dried by combined method. PMID:26575719

  20. 11S Storage globulin from pumpkin seeds: regularities of proteolysis by papain.

    PubMed

    Rudakova, A S; Rudakov, S V; Kakhovskaya, I A; Shutov, A D

    2014-08-01

    Limited proteolysis of the α- and β-chains and deep cleavage of the αβ-subunits by the cooperative (one-by-one) mechanism was observed in the course of papain hydrolysis of cucurbitin, an 11S storage globulin from seeds of the pumpkin Cucurbita maxima. An independent analysis of the kinetics of the limited and cooperative proteolyses revealed that the reaction occurs in two successive steps. In the first step, limited proteolysis consisting of detachments of short terminal peptides from the α- and β-chains was observed. The cooperative proteolysis, which occurs as a pseudo-first order reaction, started at the second step. Therefore, the limited proteolysis at the first step plays a regulatory role, impacting the rate of deep degradation of cucurbitin molecules by the cooperative mechanism. Structural alterations of cucurbitin induced by limited proteolysis are suggested to generate its susceptibility to cooperative proteolysis. These alterations are tentatively discussed on the basis of the tertiary structure of the cucurbitin subunit pdb|2EVX in comparison with previously obtained data on features of degradation of soybean 11S globulin hydrolyzed by papain. PMID:25365492

  1. Multiple antibiotic-resistant bacteria on fluted pumpkin leaves, a herb of therapeutic value.

    PubMed

    Igbeneghu, Oluwatoyin A; Abdu, Abdulrasheed B

    2014-06-01

    Fluted pumpkin (Telfairia occidentalis) is a minimally-processed green leafy vegetable traditionally used for its antianaemic properties in the form of leaf juice without a heating or inactivation step before consumption. The aim of the study was to assess the presence of surface microbiota on T. occidentalis leaves and also to determine the antimicrobial susceptibility of isolated organisms. Bacterial contaminants on 50 samples of T. occidentalis leaves were isolated and characterized using standard biochemical methods and the antimicrobial susceptibility of isolated organisms was determined using the antibiotic disc diffusion assay. The results obtained show that the leaves of T. occidentalis is contaminated with organisms which included Enterobacter agglomerans (25.9%), Proteus vulgaris (24.9%), Klebsiella spp. (2.6%), and Serratia liquefaciens (2.1%). Other bacterial isolates recovered in order of frequency included: Staphylococcus spp. (33.7%), Bacillus spp. (8.3%), and Pseudomonas fluorescens (2.6%). Of the 193 bacterial isolates from the leaves of T. occidentalis samples tested for antimicrobial resistance, all (100%) were found to be resistant to ampicillin, cloxacillin, augmentin, erythromycin, and tetracycline while 96% of the isolates were resistant to cephalothin. Resistance to trimethoprim (93%) and gentamicin (83%) was also observed. Approximately, 22% of the isolates were resistant to ciprofloxacin; however, only 11 (5.8%) were resistant to ofloxacin. Thus, uncooked T. occidentalis is a potential source of highly-resistant epiphytic bacteria which could be opportunistic pathogens in consumers. PMID:25076655

  2. Peptide hydrolase activities in seedlings and hormone-treated cotyledons of pumpkin (Cucurbita pepo).

    PubMed

    Weidhase, R A; Parthier, B

    1983-01-01

    Enzymes hydrolyzing Gly-Ala-, Met-Met- and Pro-4-phenylazo-phenylamides, and N-benzoyl-L-arginine-4-nitroanilide have been identified in germinating seeds and cotyledons of pumpkin (Cucurbita pepo). The enzyme activities per cotyledon increase markedly during the germination process, but the proportion of enhancement depends on the type of enzyme species. The increase in enzyme activities is due to de novo synthesis as shown by cycloheximide treatment and is influenced by phytohormones (cytokinins and abscissic acid). In isolated cotyledons exogenous cytokinin (benzyladenine) obviously can replace the effect of the embryo as the source of endogenous hormone. Abscissic acid counteracts the cytokinin effect. It is suggested that aminopeptidases have a biological function in reserve protein degradation of the cotyledons during seed germination. Our results do not support the assumption that the embryonic axis of the growing seedling serves as a "sink" of proteolytic products resulting in an activation of peptide hydrolases in the cotyledons, but rather de novo synthesis of these enzymes seems to be controlled by substances (phytohormones) originating from the embryo. PMID:6360167

  3. Solution properties of a heteropolysaccharide extracted from pumpkin (Cucurbita pepo, lady godiva).

    PubMed

    Song, Yi; Zhao, Jing; Ni, Yuanying; Li, Quanhong

    2015-11-01

    A water-soluble galactoglucofucomannan was extracted from pumpkin (Cucurbita pepo, lady godiva variety). GC-MS analysis indicated that the polysaccharide was composed of 1,6-linked-glucosyl, 1,2,6-linked-mannosyl, 1,3,6-linked-mannosyl, 1,2,6-linked-galactosyl, 1,2,6-linked-galactosyl, terminal fucosyl and terminal glucose. The solution properties of the polysaccharide were studied systematically by using size-exclusion chromatography combined with multi-angle laser light scattering, viscometry and dynamic light scattering at 25 °C. The weight average molecular masses (Mw), intrinsic viscosity [η], radius of gyration (Rg) and hydrodynamic radius (Rh) were found to be 12.7 × 10(5)g/mol, 780 ml/g, 68 nm and 116 nm, respectively. The fraction dimension and value of ρ (Rg/Rh) of the polysaccharide revealed that it existed in a sphere-like conformation in distilled water. The dependence of zero shear specific viscosity on the coil overlap parameter was analyzed using different models. Furthermore, degradation of samples upon autoclaving has been observed and quantified by intrinsic viscosity determination and SEC-MALLS. PMID:26256344

  4. Stable isotopic evidence for fluid flow and fluid/rock interaction during thrust faulting in Pumpkin Valley shale and Rome Formation, east Tennessee

    SciTech Connect

    Butler, B.K.; Haase, C.S. )

    1989-08-01

    The Pumpkin Valley Shale and the underlying Rome Formation form the lower portions of the Copper Creek and White Oak Mountain thrust sheets in east Tennessee. The Pumpkin Valley Shale consists of shale and mudstone with subordinate amounts of interbedded siltstone. The Rome Formation is composed predominantly of sandstone with interbedded shale and siltstone toward the base of the formation. The percentage of illite increases from 20% to over 80% of the bulk clay mineralogy toward the base of the section. Porosity is occluded by quartz, phyllosilicate, and calcite cements. Both formations contain calcite-filled and, less commonly, quartz-filled Alleghenian fractures and joints.

  5. Effects of grafting with pumpkin rootstock on carbohydrate metabolism in cucumber seedlings under Ca(NO3)2 stress.

    PubMed

    Xing, Wen-wen; Li, Lin; Gao, Pan; Li, He; Shao, Qiao-sai; Shu, Sheng; Sun, Jin; Guo, Shi-rong

    2015-02-01

    This study investigated the effects of grafting on the carbohydrate status and the enzymes of carbohydrate metabolism in self-grafted and grafted cucumber seedlings using the salt-tolerant pumpkin rootstock 'Qingzhen 1' (Cucurbita maxima × Cucurbita moschata) under 80 mM Ca(NO3)2 stress for 6 d. The growth of self-grafted seedlings was significantly inhibited after the treatment of Ca(NO3)2 stress, whereas the inhibition of growth was alleviated in pumpkin rootstock-grafted seedlings. Ca(NO3)2 stress increased the contents of the total soluble sugar, sucrose and fructose, but decreased the starch content in rootstock-grafted leaves. However, compared with self-grafted plants, rootstock-grafted seedlings were observed with a higher content of sucrose and total soluble sugar (TSS) under salt stress. Rootstock-grafted seedlings exhibited higher activities of acid invertase (AI), neutral invertase (NI) and phosphate sucrose synthase (SPS) of sucrose metabolism in leaves than that of self-grafted seedlings under salinity. Moreover, the activities of fructokinase (FK), hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) of glycolysis were maintained at a higher level in leaves of rootstock-grafted seedlings after Ca(NO3)2 stress. Additionally, rootstock-grafting decrease the high percentage enhancement of key enzymes gene expression in glycolysis in the scion leaves of cucumber seedlings induced by salt stress. These results suggest that the rootstock-grafting improved salt tolerance, which might play a role in elevated sucrose metabolism and a glycolytic pathway regulated by the pumpkin rootstock. PMID:25579659

  6. Influence of honey bee, Apis mellifera, hives and field size on foraging activity of native bee species in pumpkin fields.

    PubMed

    Artz, Derek R; Hsu, Cynthia L; Nault, Brian A

    2011-10-01

    The purpose of this study was to identify bee species active in pumpkin fields in New York and to estimate their potential as pollinators by examining their foraging activity. In addition, we examined whether foraging activity was affected by either the addition of hives of the honey bee, Apis mellifera L., or by field size. Thirty-five pumpkin (Cucurbita spp.) fields ranging from 0.6 to 26.3 ha, 12 supplemented with A. mellifera hives and 23 not supplemented, were sampled during peak flowering over three successive weeks in 2008 and 2009. Flowers from 300 plants per field were visually sampled for bees on each sampling date. A. mellifera, Bombus impatiens Cresson, and Peponapis pruinosa (Say) accounted for 99% of all bee visits to flowers. A. mellifera and B. impatiens visited significantly more pistillate flowers than would be expected by chance, whereas P. pruinosa showed no preference for visiting pistillate flowers. There were significantly more A. mellifera visits per flower in fields supplemented with A. mellifera hives than in fields not supplemented, but there were significantly fewer P. pruinosa visits in supplemented fields. The number of B. impatiens visits was not affected by supplementation, but was affected by number of flowers per field. A. mellifera and P. pruinosa visits were not affected by field size, but B. impatiens visited fewer flowers as field size increased in fields that were not supplemented with A. mellifera hives. Declining A. mellifera populations may increase the relative importance of B. impatiens in pollinating pumpkins in New York. PMID:22251726

  7. Can Stable Isotope combined with Trace Element Analysis distinguish between pure and g.g.A. (protected geographical indication, P.G.I.) certified Pumpkin Seed Oils?

    NASA Astrophysics Data System (ADS)

    Meier-Augenstein, Wolfram; Kemp, Helen; Midwood, Andy

    2013-04-01

    Styrian Pumpkin Seed Oil is a premium single seed vegetable oil that is uniquely linked to the geographic region of Styria where it is grown and produced. In 1996, the strong regional ties of this typical Styrian speciality were recognised by the EU-Commission who declared "Styrian Pumpkin Seed Oil P.G.I." as a Protected Geographical Indication (article 5 VO(EWG) Nr. 2081/92). In 1998, more than 2,000 domestic pumpkin seed producers and 30 oil mills formed an association of Styrian pumpkin seed oil producers, which is now called the "Gemeinschaft Steirisches Kürbiskernöl g.g.A.". This producers' association was formed in order to protect the regionality and the high quality of Styrian Pumpkin Seed Oil P.G.I. Procedures implemented by this producers' association document every step in the process from pumpkin seeds to seed crushing in oil mills and finally bottling of Styrian Pumpkin Seed Oil P.G.I., keeping a contiguous record of all production steps including annual harvest amounts. This permits full traceability of every bottle of Styrian Pumpkin Seed Oil P.G.I from harvest to the finished, bottled products found on the shelf of delis and even supermarkets. Despite these efforts of the producers' association, there have been repeated claims of g.g.A. (P.G.I.) certified bottles of Styrian Pumpkin Seed Oil (PSO) having been analysed independently and shown to contain either mixtures of Styrian and non-Styrian PSO or no Styrian PSO at all. Since keeping records of annual harvest amounts of pumpkin seeds would make it very difficult for an "over-production" by mixing or substitution of alien PSO's to go unnoticed, we formed the hypothesis that the red-flagged bottles could have been counterfeits containing alien PSO with bottles sporting fake g.g.A. seals and fake serial numbers. An alternative hypothesis was that the chosen method of detection of allegedly misrepresented g.g.A. Styrian PSO resulted in a high number of false negatives thus incorrectly rejecting

  8. Application of edible coating with starch and carvacrol in minimally processed pumpkin.

    PubMed

    Santos, Adriele R; da Silva, Alex F; Amaral, Viviane C S; Ribeiro, Alessandra B; de Abreu Filho, Benicio A; Mikcha, Jane M G

    2016-04-01

    The present study evaluated the effect of an edible coating of cassava starch and carvacrol in minimally processed pumpkin (MPP). The minimal inhibitory concentration (MIC) of carvacrol against Escherichia coli, Salmonella enterica serotype Typhimurium, Aeromonas hydrophila, and Staphylococcus aureus was determined. The edible coating that contained carvacrol at the MIC and 2 × MIC was applied to MPP, and effects were evaluated with regard to the survival of experimentally inoculated bacteria and autochthonous microflora in MPP. Total titratable acidity, pH, weight loss, and soluble solids over 7 days of storage under refrigeration was also analyzed. MIC of carvacrol was 312 μg/ml. Carvacrol at the MIC reduced the counts of E. coli and S. Typhimurium by approximately 5 log CFU/g. A. hydrophila was reduced by approximately 8 log CFU/g, and S. aureus was reduced by approximately 2 log CFU/g on the seventh day of storage. Carvacrol at the 2 × MIC completely inhibited all isolates on the first day of Storage. coliforms at 35 °C and 45 °C were not detected (< 3 MPN/g) with either treatment on all days of shelf life. The treatment groups exhibited a reduction of approximately 2 log CFU/g in psychrotrophic counts compared with controls on the last day of storage. Yeast and mold were not detected with either treatment over the same period. The addition of carvacrol did not affect total titratable acidity, pH, or soluble solids and improved weight loss. The edible coating of cassava starch with carvacrol may be an interesting approach to improve the safety and microbiological quality of MPP. PMID:27413224

  9. Hypolipidemic effect of Telfairia occidentalis (fluted pumpkin) in rats fed a cholesterol-rich diet.

    PubMed

    Adaramoye, O A; Achem, J; Akintayo, O O; Fafunso, M A

    2007-06-01

    Telfairia occidentalis (fluted pumpkin) is one of the commonly consumed leafy vegetables in Nigeria. In order to justify its inclusion in herbal preparations in African traditional medicine, the possible hypolipidemic effect of this vegetable was investigated in rats fed a cholesterol-rich diet. The ability of Questran, a hypolipidemic drug, to attenuate hypercholesterolemia was also examined. Rats were fed with either a basal diet containing cholic acid (0.2%) or a supplemented diet with T. occidentalis at the 3% and 6% levels. Oral administration of cholesterol for 9 consecutive weeks resulted in a significant increase (P < .001) in the relative weight of the heart of cholesterol-fed rats. However, supplemented diets significantly (P < .001) ameliorated the cholesterol-induced enlargement of the heart. Rats fed on supplemented diets had a dose-dependent reduction in plasma and postmitochondrial supernatant fraction (PMF) cholesterol levels. In particular, supplemented diets containing 3% and 6% T. occidentalis decreased plasma and PMF cholesterol levels by 20% and 30% and by 30% and 45%, respectively. A similar decrease in plasma and PMF cholesterol levels was obtained in Questran-treated hypercholesterolemic rats. Furthermore, 3% and 6% T. occidentalis-supplemented diets significantly (P < .05) decreased the cholesterol-induced increase in plasma and PMF low-density lipoprotein (LDL) cholesterol levels by 24% and 48% and by 28% and 52%, respectively. In contrast, there was no significant difference (P > .05) in plasma and PMF triglyceride levels of rats fed on supplemented diets when compared with cholesterol-fed rats. There were significant decreases (P < .05) in lipid peroxidation levels in rats fed on the supplemented diets. Specifically, 3% and 6% T. occidentalis-supplemented diets decreased plasma and PMF lipid peroxidation by 24% and 20% and by 42% and 21%, respectively. This study demonstrates that T. occidentalis may be a useful therapy for

  10. Pumpkin-seed oil modulates the effect of felodipine and captopril in spontaneously hypertensive rats.

    PubMed

    Zuhair, H A; Abd El-Fattah, A A; El-Sayed, M I

    2000-05-01

    Natural products like pumpkin-seed oil (PSO) may modify the potency of the calcium antagonist felodipine (FEL) or angiotensin-converting enzyme inhibitor (ACE-inhibitor), captopril (CPT) in modulating the biochemical derangement in blood, heart and kidney as well as blood pressure and heart rate of spontaneously hypertensive rats (SHR) were investigated. SHR were treated orally with FEL at a dose of 0. 45 mg kg(-1) body wt. or CPT at a dose of 9 mg kg(-1) body wt. once daily for 4 weeks. PSO was administered at a dose of 40 mg kg(-1) body wt. alone or with FEL or CPT in the previous respective dose regimen for the same period to SHR. This study showed that hypertension induced increments the content of malondialdehyde (MDA) by 55% and 38% as well as the activity of glutathione peroxidase (GSH-Px) by 26% and 23% in heart and kidney, respectively, accompanied by reductions in the activity of myocardial superoxide dismutase (SOD) from 3.40+/-0.17 to 2.42+/-0.19 U mg protein(-1)and contents of glutathione (GSH) and protein thiols (PrSHs) in different tissues of SHR as compared to normotensive rats. Treatment of SHR with FEL or CPT monotherapy or combined with PSO produced improvement in the measured free radical scavengers in the heart and kidney. Our results also showed that pretreatment of SHR with PSO for 4 weeks then i.v. administration of FEL or CPT produced a significant beneficial hypotensive action. The results were explained in the light of the antioxidant properties of PSO. Therefore, it is concluded that concomitant administration of FEL or CPT with natural antioxidants can yield a beneficial therapeutic effect and retard the progression of hypertension. PMID:10753555

  11. Effects of Dietary Fiber Extracted from Pumpkin (Cucurbita maxima Duch.) on the Physico-Chemical and Sensory Characteristics of Reduced-Fat Frankfurters

    PubMed Central

    Kim, Cheon-Jei; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Ham, Youn-Kyung; Choi, Ji-Hun

    2016-01-01

    In this study, we investigated the effects of reducing fat levels from 30% to 25, 20, and 15% by substituting pork fat with water and pumpkin fiber (2%) on the quality of frankfurters compared with control. Decreasing the fat concentration from 30% to 15% significantly increased moisture content, redness of meat batter and frankfurter, cooking loss, and water exudation, and decreased fat content, energy value, pH, and lightness of meat batter and frankfurter, hardness, cohesiveness, gumminess, chewiness, and apparent viscosity. The addition of 2% pumpkin fiber was significantly increased moisture content, yellowness of meat batter and frankfurter, hardness, cohesiveness, gumminess, chewiness, and apparent viscosity, whereas reduced cooking loss and emulsion stability. The treatment of reduced-fat frankfurters formulated with 20 and 25% fat levels and with pumpkin fiber had sensory properties similar to the high-fat control frankfurters. The results demonstrate that when the reduced-fat frankfurter with 2% added pumpkin fiber and water replaces fat levels can be readily made with high quality and acceptable sensory properties. PMID:27433101

  12. Effects of Dietary Fiber Extracted from Pumpkin (Cucurbita maxima Duch.) on the Physico-Chemical and Sensory Characteristics of Reduced-Fat Frankfurters.

    PubMed

    Kim, Cheon-Jei; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Ham, Youn-Kyung; Choi, Ji-Hun; Kim, Young-Boong; Choi, Yun-Sang

    2016-01-01

    In this study, we investigated the effects of reducing fat levels from 30% to 25, 20, and 15% by substituting pork fat with water and pumpkin fiber (2%) on the quality of frankfurters compared with control. Decreasing the fat concentration from 30% to 15% significantly increased moisture content, redness of meat batter and frankfurter, cooking loss, and water exudation, and decreased fat content, energy value, pH, and lightness of meat batter and frankfurter, hardness, cohesiveness, gumminess, chewiness, and apparent viscosity. The addition of 2% pumpkin fiber was significantly increased moisture content, yellowness of meat batter and frankfurter, hardness, cohesiveness, gumminess, chewiness, and apparent viscosity, whereas reduced cooking loss and emulsion stability. The treatment of reduced-fat frankfurters formulated with 20 and 25% fat levels and with pumpkin fiber had sensory properties similar to the high-fat control frankfurters. The results demonstrate that when the reduced-fat frankfurter with 2% added pumpkin fiber and water replaces fat levels can be readily made with high quality and acceptable sensory properties. PMID:27433101

  13. Genetic relationships in Cucurbita pepo (pumpkin, squash, gourd) as viewed with high frequency oligonucleotide–targeting active gene (HFO–TAG) markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cucurbita pepo is a highly diverse, economically important member of the Cucurbitaceae. C. pepo encompasses hundreds of cultivars of pumpkins, squash, and gourds. Although C. pepo has been scrutinized with various types of DNA markers, the relationships among the cultivar-groups of C. pepo subsp. p...

  14. Effect of drying and co-matrix addition on the yield and quality of supercritical CO₂ extracted pumpkin (Cucurbita moschata Duch.) oil.

    PubMed

    Durante, Miriana; Lenucci, Marcello S; D'Amico, Leone; Piro, Gabriella; Mita, Giovanni

    2014-04-01

    In this work a process for obtaining high vitamin E and carotenoid yields by supercritical carbon dioxide (SC-CO₂) extraction from pumpkin (Cucurbita moschata Duch.) is described. The results show that the use of a vacuum oven-dried [residual moisture (∼8%)] and milled (70 mesh sieve) pumpkin flesh matrix increased SC-CO₂ extraction yields of total vitamin E and carotenoids of ∼12.0- and ∼8.5-fold, respectively, with respect to the use of a freeze-dried and milled flesh matrix. The addition of milled (35 mesh) pumpkin seeds as co-matrix (1:1, w/w) allowed a further ∼1.6-fold increase in carotenoid yield, besides to a valuable enrichment of the extracted oil in vitamin E (274 mg/100 g oil) and polyunsaturated fatty acids. These findings encourage further studies in order to scale up the process for possible industrial production of high quality bioactive ingredients from pumpkin useful in functional food or cosmeceutical formulation. PMID:24262563

  15. Stereospecific analysis of triacylglycerols as a useful means to evaluate genuineness of pumpkin seed oils: lesson from virgin olive oil analyses.

    PubMed

    Butinar, Bojan; Bucar-Miklavcic, Milena; Valencic, Vasilij; Raspor, Peter

    2010-05-12

    In Slovenia two superb vegetable oils with high added nutritional value are produced: "Ekstra devisko oljcno olje Slovenske Istre (extra virgin olive oil from Slovene Istra)" and "Stajersko prekmursko bucno olje (pumpkin seed oil from Slovenia)". Their quality and genuineness must be monitored as adulteration can easily be undertaken. Olive oil genuineness determination experiences can show how analyses following an experience data-driven decision tree gathering several chemical determinations (fatty acids, (E)-isomers of fatty acids, sterol and tocopherol determinations) may be helpful in assessing the pumpkin seed oil from Slovenia genuineness. In the present work a set of HPLC triacylglycerol determinations was performed, based on the nine main triacylglycerols (LLLn, LLL, PLL, LOO, PLO, OOO, POO, SPL, and SLS) on a limited number of different pumpkin seed oils from northeastern Slovenia. The performed determinations showed that stereospecific analyses of triacylglycerols together with other chemical determinations can be useful in building a protocol for the evaluation of the genuineness of pumpkin seed oil from Slovenia. PMID:20380471

  16. Effect of pumpkin seed (Cucurbita pepo) protein isolate on the activity levels of certain plasma enzymes in CCl4-induced liver injury in low-protein fed rats.

    PubMed

    Nkosi, C Z; Opoku, A R; Terblanche, S E

    2005-04-01

    The effects of pumpkin seed (Cucurbita pepo) protein isolate on the activity levels of lactate dehydrogenase (LD), alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) against carbon tetrachloride (CCl4)-induced acute liver injury in low-protein fed rats were investigated. A group of male Sprague-Dawley rats maintained on a low-protein diet for 5 days were divided into three subgroups. Two subgroups were injected with carbon tetrachloride and the other group with an equivalent amount of olive oil. Two hours after CCl4 intoxication one of the two subgroups was administered with pumpkin seed protein isolate. All three subgroups of rats were maintained on the low-protein diet for the duration of the investigation. Groups of rats from the different subgroups were killed at 24, 48 and 72 h after their respective treatments. After 5 days on the low-protein diet the activity levels of all four enzymes were significantly higher than their counterparts on a normal balanced diet. CCl4 intoxication resulted in significant increases in the activity levels of all four enzymes investigated. The administration of pumpkin seed protein isolate after CCl4 intoxication resulted in significantly reduced activity levels of all four enzymes. It is concluded that pumpkin seed protein isolate administration was effective in alleviating the detrimental effects associated with protein malnutrition. PMID:16041732

  17. Preparation and properties of flours and protein concentrates from raw, fermented and germinated fluted pumpkin (Telfairia occidentalis Hook) seeds.

    PubMed

    Giami, S Y; Isichei, I

    1999-01-01

    In vitro protein digestibility, chemical composition and selected functional properties of flours and protein concentrates prepared from raw, fermented and germinated fluted pumpkin (Telfairia occidentalis Hook) seeds were studied. Protein concentrates prepared by an alkaline extraction process had increased crude protein contents (61.5-70.8%) compared to flour samples (46.4-52.7%). The yields of protein concentrates ranged from 24.5% to 29.4% while values for protein recoveries varied between 64.8% and 65.2%. Protein concentrates also had increased foam volume and decreased foam stability (100% decrease over a 2 h period), compared to flour samples. Fermentation and germination were observed to significantly (p < 0.05) lower polyphenol and phytic acid contents, but increased protein digestibility of fluted pumpkin seed flours and concentrates. Both raw flour and concentrate were significantly (p < 0.05) higher in water absorption capacity than germinated or fermented flours and concentrates. Protein concentrates had comparatively better fat absorption properties than the flour samples. Hence protein concentrates may prove to have useful applications in ground meat formulations. PMID:10646631

  18. Use of video surveillance to measure the influences of habitat management and landscape composition on pollinator visitation and pollen deposition in pumpkin (Cucurbita pepo) agroecosystems

    PubMed Central

    Phillips, Benjamin W.

    2015-01-01

    Pumpkin (Cucurbita pepo) production relies on insect-mediated pollination, which is provided by managed and wild pollinators. The goals of this study were to measure the visitation frequency, longevity and temporal activity patterns of pumpkin pollinators and to determine if local habitat management and landscape composition affected this pollination service. We used video surveillance to monitor bee acitivty within male and female pumpkin flowers in 2011 and 2012 across a pollination window of 0600–1200 h. We also quantified the amount of pollen deposited in female flowers across this time period. In 2011, A. mellifera made significantly more floral visits than other bees, and in 2012 Bombus spp. was the dominant pumpkin pollinator. We found variation in visitation among male and female pumpkin flowers, with A. mellifera visiting female flowers more often and spending longer per visit within them than male flowers in both 2011 and 2012. The squash bee P. pruinosa visited male flowers more frequently in 2012, but individuals spent equal time in both flower sexes. We did not find variation in the timing of flower visitation among species across the observed pollination window. In both 2011 and 2012 we found that the majority of pollen deposition occurred within the first two hours (0600–0800 h) of observation; there was no difference between the pollen deposited during this two-hour period and full pollination window (0600–1200 h). Local additions of sweet alyssum floral strips or a field buffer strip of native wildflowers did not have an effect on the foraging activity of bees or pollen deposition. However, semi-natural and urban habitats in the surrounding landscape were positively correlated with the frequency of flower visitation by wild pollinators and the amount of pollen deposited within female flowers. PMID:26587337

  19. 87Sr/88Sr a useful tool for the identification of geographic origin of Styrian pumpkin seed oils?

    NASA Astrophysics Data System (ADS)

    Meisel, T.; Bandoniene, D.; Zettl, D.; Maneiko, M.; Horschinegg, M.

    2012-04-01

    The authenticity and the geographic origin of Styrian pumpkin seed oil (PGI) a regional specialty needs to be protected, but the current specification of this high priced product does not include the proof of origin through analytical tools. As it turns out, this and many other products within the Protected Geographical Status (PGS) framework of the European Union, cannot be protected from fraud without forensic tools. In previous studies we were able to demonstrate, that distribution and content of trace elements in particular the rare earth elements, are useful parameters to discriminate Austrian from non-Austrian pumpkin seed oils and seeds. Unlike stable isotopes ratios (C and H), the trace element patterns are not influenced by changes in weather conditions and temperature during growing and harvesting cycle. Though the study of the distribution of element traces can be used not only for the identification of the geographic origin with very useful PLS and PCA models but also can identify fraud through mixing with other oils, this method need to be validated by other means. Radiogenic isotopes, in particular the 87Sr/86Sr isotope amount ratio has been successfully applied to food and other products for forensic studies. In this study we determined the 87Sr/86Sr isotope amount ratio in pumpkin seed oils extracted from seeds of known geographic origin from Austria, Russia and China, as these are the largest producers, to see if significant differences occur and if they can be used as a forensic tool. Although the total area of the Russian and the Chinese crop fields are magnitudes larger than the ones from Austria, it turns out that the variance of the Austrian 87Sr/86Sr data is much larger than that from other sources. Reasons are the large diversity of the Austrian geology (pre-varsican, alpine to sub-recent ages of the underlying bedrock of the soils can be found), the small farm sizes and the small scale production. In Russia large farms are situated on

  20. Antioxidative effects of pumpkin seed (Cucurbita pepo) protein isolate in CCl4-induced liver injury in low-protein fed rats.

    PubMed

    Nkosi, C Z; Opoku, A R; Terblanche, S E

    2006-11-01

    The effects of pumpkin seed (Cucurbita pepo) protein isolate on the plasma activity levels of catalase (CA), superoxide dismutase (SOD), glutathione peroxidase (GSHpx) and total antioxidant capacity (TAC) as well as glucose-6-phosphatase (G6Pase) in liver homogenates and lipid peroxidation (LPO-malondialdehyde-MDA) levels in liver homogenates and liver microsomal fractions against carbon tetrachloride (CCl(4))-induced acute liver injury in low-protein fed Sprague-Dawley rats (Rattus norvegicus) were investigated. A group of male Sprague-Dawley rats maintained on a low-protein diet for 5 days were divided into three subgroups. Two subgroups were injected with carbon tetrachloride and the other group with an equivalent amount of olive oil. Two hours after CCl(4) intoxication one of the two subgroups was administered with pumpkin seed protein isolate and thereafter switched onto a 20% pumpkin seed protein isolate diet. The other two groups of rats were maintained on the low-protein diet for the duration of the investigation. Groups of rats from the different subgroups were killed at 24, 48 and 72 h after their respective treatments. After 5 days on the low-protein diet the activity levels of all the enzymes as well as antioxidant levels were significantly lower than their counterparts on a normal balanced diet. However, a low-protein diet resulted in significantly increased levels of lipid peroxidation. The CCl(4) intoxicated rats responded in a similar way, regarding all the variables investigated, to their counterparts on a low-protein diet. The administration of pumpkin seed protein isolate after CCl(4) intoxication resulted in significantly increased levels of all the variables investigated, with the exception of the lipid peroxidation levels which were significantly decreased. From the results of the present study it is concluded that pumpkin seed protein isolate administration was effective in alleviating the detrimental effects associated with protein

  1. Age and quality of ground water and sources of nitrogen in the aquifers in Pumpkin Creek Valley, western Nebraska, 2000

    USGS Publications Warehouse

    Steele, G.V.; Cannia, J.C.; Sibray, S.S.; McGuire, V.L.

    2005-01-01

    Ground water is the source of drinking water for the residents of Pumpkin Creek Valley, western Nebraska. In this largely agricultural area, shallow aquifers potentially are susceptible to nitrate contamination. During the last 10 years, ground-water levels in the North Platte Natural Resources District have declined and contamination has become a major problem for the district. In 2000, the U.S. Geological Survey and the North Platte Natural Resources District began a cooperative study to determine the age and quality of the ground water and the sources of nitrogen in the aquifers in Pumpkin Creek Valley. Water samples were collected from 8 surface-water sites, 2 springs, and 88 ground-water sites during May, July, and August 2000. These samples were analyzed for physical properties, nutrients or nitrate, and hydrogen and oxygen isotopes. In addition, a subset of samples was analyzed for any combination of chlorofluorocarbons, tritium, tritium/helium, sulfur-hexafluoride, carbon-14, and nitrogen-15. The apparent age of ground water in the alluvial aquifer typically varied from about 1980 to modern, whereas ground water in the fractured Brule Formation had a median value in the 1970s. The Brule Formation typically contained ground water that ranged from the 1940s to the 1990s, but low-yield wells had apparent ages of 5,000 to 10,000 years before present. Data for oxygen-18 and deuterium indicated that lake-water samples showed the greatest effects from evaporation. Ground-water data showed no substantial evaporative effects and some ground water became isotopically heavier as the water moved downgradient. In addition, the physical and chemical ground-water data indicate that Pumpkin Creek is a gaining stream because little, if any, of its water is lost to the ground-water system. The water-quality type changed from a sodium calcium bicarbonate type near Pumpkin Creek's headwaters to a calcium sodium bicarbonate type near its mouth. Nitrate concentrations were

  2. Nutritional evaluation of phosphorylated pumpkin seed (Cucurbita moschata) protein concentrate in silver catfish Rhamdia quelen (Quoy and Gaimard, 1824).

    PubMed

    Lovatto, Naglezi de Menezes; Goulart, Fernanda Rodrigues; de Freitas, Silvandro Tonetto; Mombach, Patricia Inês; Loureiro, Bruno Bianch; Bender, Ana Betine Beutinger; Boligon, Aline Augusti; Radünz Neto, João; da Silva, Leila Picolli

    2015-12-01

    An 8-week feeding trial was conducted to evaluate the effect of replacing fish meal with pumpkin seed meal (PSM) or phosphorylated protein concentrate of pumpkin seed meal (PPCPS) on growth and metabolic responses of silver catfish. Five isonitrogenous and isocaloric diets were formulated. Control diet contained fish meal as the main protein source. The treatment groups contained 25 and 50% of either PSM or PPCPS protein replaced the fishmeal protein. A total of 400 silver catfish, with initial mean weight of 24 ± 0.46 g, were distributed into 20 tanks. For data four orthogonal contrasts were applied: control diet versus PSM diets; control diets versus PPCPS diets; control versus other diets; PSM diets versus PPCPS diets. The results indicated that the fish fed PSM diets had lower weight gain when compared to either control diet or PPCPS. The PPCPS do not affect growth and protein efficiency ratio. Lower albumin contents were found for the control diet fish for the contrasts control diet versus PPCPS diet and control diet versus other diets. The hepatic ALAT enzyme activity was higher in the fish fed the control diet (P < 0.05). The hepatic ALP was most active in fish that received the PPCPS diets, when comparing control diet versus PPCPS diets and control diet versus other diets. The hepatosomatic index was higher for fish fed the PPCPS. Our results indicated that PPCPS presents relevant nutritional quality for fish and can replace the fish meal protein up to 50% without affecting growth, PER and intermediate metabolites in silver catfish. PMID:26377938

  3. Protective effect of combined pumpkin seed and ginger extracts on sperm characteristics, biochemical parameters and epididymal histology in adult male rats treated with cyclophosphamide.

    PubMed

    Aghaie, Somaieh; Nikzad, Hossein; Mahabadi, Javad Amini; Taghizadeh, Mohsen; Azami-Tameh, Abolfazl; Taherian, Aliakbar; Sajjadian, Seyyed Mohammad Sajjad; Kamani, Mehran

    2016-09-01

    Reproductive toxicity is one of the side effects of cyclophosphamide (CP) in cancer treatment. Pumpkin seeds and Zingiber officinale are natural sources of antioxidants. We investigated the possible protective effect of combined pumpkin seed and Zingiber officinale extracts on sperm characteristics, epididymal histology and biochemical parameters of CP-treated rats. Male adult Wistar rats were divided randomly into six groups. Group 1, as a control, received an isotonic saline solution injection intraperitoneally (IP). Group 2 were injected IP with a single dose of CP (100 mg/kg) once. Groups 3 and 4 received CP plus 300 and 600 mg/kg combined pumpkin seed and Zingiber officinale extract (50:50). Groups 5 and 6 received only 300 and 600 mg/kg combined pumpkin seed and Zingiber officinale extract. Six weeks after treatment, sperm characteristics, histopathological changes and biochemical parameters were assessed. In CP-treated rats, motile spermatozoa were decreased, and abnormal or dead spermatozoa increased significantly (P < 0.001) but administration of the mixed extract improved sperm parameters. Epididymal epithelium and fibromascular thickness were also improved in extract-treated rats compared to control or CP groups. Biochemical analysis showed that the administration of combined extracts could increase the total antioxidant capacity (TAC) level significantly in groups 3, 4, 5 and 6. Interestingly, the mixed extract could decrease most of the side effects of CP such as vacuolization and separation of epididymal tissue. Our findings indicated that the combined extracts might be used as a protective agent against CP-induced reproductive toxicity. PMID:26714700

  4. Comparison of semi-batch vs. continuously fed anaerobic bioreactors for the treatment of a high-strength, solids-rich pumpkin-processing wastewater.

    PubMed

    del Agua, Isabel; Usack, Joseph G; Angenent, Largus T

    2015-01-01

    The objective of this work was to compare two different high-rate anaerobic bioreactor configurations--the anaerobic sequencing batch reactor (ASBR) and the upflow anaerobic solid removal (UASR) reactor--for the treatment of a solid-rich organic wastewater with a high strength. The two, 4.5-L reactors were operated in parallel for close to 100 days under mesophilic conditions (37°C) with non-granular biomass by feeding a pumpkin wastewater with ∼4% solids. The organic loading rate of pumpkin wastewater was increased periodically to a maximum of 8 g COD L(-1) d(-1) by shortening the hydraulic retention time to 5.3 days. Compositional analysis of pumpkin wastewater revealed deficiencies in the trace metal cobalt and alkalinity. With supplementation, the ASBR outperformed the UASR reactor with total chemical oxygen demand (COD) removal efficiencies of 64% and 53%, respectively, achieving a methane yield of 0.27 and 0.20 L CH4 g(-1) COD fed to the ASBR and UASR, respectively. The better performance realized with the ASBR and this specific wastewater was attributed to its semi-batch, dynamic operating conditions rather than the continuous operating conditions of the UASR reactor. PMID:25683478

  5. In vivo metabolism of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in young whole pumpkin plant.

    PubMed

    Sun, Jianteng; Liu, Jiyan; Yu, Miao; Wang, Chang; Sun, Yuzhen; Zhang, Aiqian; Wang, Thanh; Lei, Zhen; Jiang, Guibin

    2013-04-16

    Polybrominated diphenyl ethers (PBDEs) are widely distributed persistent organic pollutants. In vitro and in vivo research using various animal models have shown that PBDEs might be transformed to hydroxylated PBDEs, but there are few studies on in vivo metabolism of PBDEs by intact whole plants. In this research, pumpkin plants (Cucurbita maxima × C. moschata) were hydroponically exposed to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47). A debromination product (BDE-28) and four hydroxylated metabolites (5-OH-BDE-47, 6-OH-BDE-47, 4'-OH-BDE-49, and 4-OH-BDE-42) were detected in different parts of the whole plant. In addition, 4-methoxylated-2,2',3,4'-tetraBDE (4-MeO-BDE-42) was observed as a methoxylation product. Root exudates in solution were found to play an important role in metabolizing BDE-47 to a specific OH-PBDE: 4'-OH-BDE-49. BDE-28 was found to translocate more easily and accumulate in shoots than BDE-47 due to the lower hydrophobicity and molecular weight. The concentration ratio between metabolites and parent compound BDE-47 was lower for OH-PBDEs than that for both BDE-28 and 4-MeO-BDE-42. The metabolism pathway of BDE-47 in young whole plants was proposed in this study. PMID:23510101

  6. Metabolites of 2,4,4'-tribrominated diphenyl ether (BDE-28) in pumpkin after in vivo and in vitro exposure.

    PubMed

    Yu, Miao; Liu, Jiyan; Wang, Thanh; Sun, Jianteng; Liu, Runzeng; Jiang, Guibin

    2013-01-01

    There is currently limited knowledge on PBDE metabolism in plants although they could play an important role in the environmental transformation of these persistent organic pollutants. In this study, pumpkin (Cucurbita maxima × C. moschata) was chosen as the model to understand the fate of BDE-28 in plants. MeO-tri-BDEs, OH-tri-BDEs, and OH-tri-BDEs were found as metabolites in plant samples of both in vivo hydroponic and in vitro tissue culture exposure. Three MeO-tri-BDEs were further identified as para-substituted metabolites. MeO-BDEs and OH-BDEs, respectively, accounted for about 1.6% and 1.5% (recovery corrected) of initial amount of BDE-28 according to the semiquantitative results. Other PBDEs, especially less brominated PBDEs as impurities in the standard of BDE-28, were also detected. The impurities and evaporation of the standard must be considered when trace metabolites are studied in exposure experiments. PMID:24191731

  7. Protective effect of ellagic acid and pumpkin seed oil against methotrexate-induced small intestine damage in rats.

    PubMed

    El-Boghdady, Noha A

    2011-12-01

    Gastrointestinal toxicity is one of the most serious side effects in the methotrexate (MTX) treatment. This study was designed to investigate whether ellagic acid (EA) and/or pumpkin seed oil (PSO) had a protective effect on MTX-induced small intestine damage. Forty albino rats were randomized into five groups of 8 rats each. Group I served as a normal control group. In Group II, MTX was administered as a single dose (20 mg/kg) intraperitoneally. Groups III, IV and V were pre-treated respectively with either PSO (40 mg/kg), EA (10 mg/kg) or 0.2% DMSO (vehicle control) orally every day by gavage for 5 days and then they received MTX. All animals were sacrificed 5 days after the intraperitoneal injection of MTX for histopathological examination, estimation of serum prostaglandin E2 (PGE2) level, assay of tissue malondialdehyde (MDA), reduced glutathione (GSH) and nitric oxide (NO) levels and myloperoxidase (MPO), xanthine oxidase (XO) and adenosine deaminase (AD) activities. Administration of EA and/or PSO decreased the intestinal damage, PGE2, MDA and NO levels and MPO, XO and AD activities and increased GSH level. These results suggest that EA and PSO protect the small intestine of rats from MTX-induced damage through their antioxidant and anti-inflammatory effects and thus have potential as a promising drug in the prevention of undesired side effects of MTX. PMID:22329239

  8. Effect of pumpkin-seed oil on the level of free radical scavengers induced during adjuvant-arthritis in rats.

    PubMed

    Fahim, A T; Abd-el Fattah, A A; Agha, A M; Gad, M Z

    1995-01-01

    Pumpkin-seed oil (PSO), a natural supplement rich with antioxidant ingredients, was given to rats in which arthritis was induced using Freund's complete adjuvant. Its effect was compared with that of indomethacin, as a classical anti-inflammatory agent. Two experimental patterns were studied, an acute phase that was applied only with PSO and a chronic phase applied for both PSO and indomethacin. Compared to normal untreated rats, it was shown that the induction of arthritis caused a decrease in serum sulphhydryl groups, with an increase in serum ceruloplasmin in both phases. Blood glutathione was first elevated in the acute phase, then its level was reduced in the chronic phase. Serum N-acetyl-beta-D-glucosaminidase activity was elevated only at the acute phase, while plasma total proteins and albumin were reduced at the chronic phase. Liver glucose-6-phosphate dehydrogenase activity was markedly increased, while no changes were observed in the levels of liver lipid peroxides and glutathione. These changes in the studied parameters were attributed to the superoxides and free radicals during arthritic inflammation. Administration of PSO succeeded in modulating most of the altered parameters affected during arthritis, especially at the chronic phase. Also, a remarkable inhibition of paw oedema was observed. A similar pattern was obtained upon treatment with indomethacin except that indomethacin markedly elevated liver lipid peroxides levels. Concurrent administration of PSO with indomethacin caused no changes in the parameters studied compared to that induced by treatment with indomethacin alone. PMID:7784309

  9. Authentication of vegetable oils by bulk and molecular carbon isotope analyses with emphasis on olive oil and pumpkin seed oil.

    PubMed

    Spangenberg, J E; Ogrinc, N

    2001-03-01

    The authenticity of vegetable oils consumed in Slovenia and Croatia was investigated by carbon isotope analysis of the individual fatty acids by the use of gas chromatography-combustion-isotope ratio mass spectrometry (GC/C/IRMS), and through carbon isotope analysis of the bulk oil. The fatty acids from samples of olive, pumpkin, sunflower, maize, rape, soybean, and sesame oils were separated by alkaline hydrolysis and derivatized to methyl esters for chemical characterization by capillary gas chromatography/mass spectrometry (GC/MS) prior to isotopic analysis. Enrichment in heavy carbon isotope ((13)C) of the bulk oil and of the individual fatty acids are related to (1) a thermally induced degradation during processing (deodorization, steam washing, or bleaching), (2) hydrolytic rancidity (lipolysis) and oxidative rancidity of the vegetable oils during storage, and (3) the potential blend with refined oil or other vegetable oils. The impurity or admixture of different oils may be assessed from the delta(13)C(16:0) vs. delta(13)C(18:1) covariations. The fatty acid compositions of Slovenian and Croatian olive oils are compared with those from the most important Mediterranean producer countries (Spain, Italy, Greece, and France). PMID:11312892

  10. Evaluation of the potential of squash pumpkin by-products (seeds and shell) as sources of antioxidant and bioactive compounds.

    PubMed

    Saavedra, M J; Aires, A; Dias, C; Almeida, J A; De Vasconcelos, M C B M; Santos, P; Rosa, E A

    2015-02-01

    The transformation of byproducts and wastes generated by agro-food companies is of high importance since only a small portion of plant material is utilized directly for human consumption. Squash pumpkin is greatly used in Portugal and as by-products of its processing are generated tons of shell and seeds. In this study we aim to evaluate the potential of these wastes as sources of beneficial and bioactive compounds (antioxidants and antimicrobials), studying the effect of different extraction solvents and drying methods. The samples (fresh and cooked) were freeze-dried and oven-dried followed by extraction with different solvents that revealed the following decreasing order of efficiency: 70 % ethanol, 70 % methanol, 70 % acetone, ultra-pure water and 100 % dichloromethane. The oven-dried samples showed higher values of antioxidant activity and phenolic content, with exception of the values of phenolics for the seeds material. The shell samples presented higher values (1.47 - 70.96 % inhibition) of antioxidant activity and total phenolic content (2.00 - 10.69 mg GAE/g DW). A positive correlation was found between these two parameters on the shell samples, however the squash seeds revealed a negative correlation between the phenolic content and the antioxidant activity. The results show that these industrial agro-food residues are potentially good sources of bioactive compounds with health benefits. PMID:25694712

  11. Geological and petrological considerations relevant to the disposal of radioactive wastes by hydraulic fracturing: an example at the US Department of Energy's Oak Ridge National Laboratory. [Pumpkin Valley shales

    SciTech Connect

    Haase, C.S.

    1982-01-01

    At Oak Ridge National Laboratory the Pumpkin Valley Shale is used as a host formation for hydraulic-fracturing waste disposal. Determination of the relationships between the distribution of different lithologies and porosity-permeability trends within this host formation allows these properties, important to hydraulic-fracturing operations, to be related to measurable and mappable geological and petrological parameters. It also permits extrapolation of such patterns to little-studied portions of the Pumpkin Valley Shale. Such knowledge better allows for the satisfactory operation and assessment of the hydraulic fracturing at Oak Ridge National Laboratory.

  12. Grafting-responsive miRNAs in cucumber and pumpkin seedlings identified by high-throughput sequencing at whole genome level.

    PubMed

    Li, Chaohan; Li, Yansu; Bai, Longqiang; Zhang, Tieyao; He, Chaoxing; Yan, Yan; Yu, Xianchang

    2014-08-01

    Grafting is an important agricultural technique widely used for improving growth, yields and tolerance of crops to abiotic and biotic stresses. As one type of endogenous, non-coding small RNAs, microRNAs (miRNAs) regulate development and responsiveness to biotic and abiotic stresses by negatively mediating expression of target genes at the post-transcriptional level. However, there have been few detailed studies to evaluate the role of miRNAs in mediation of grafting-induced physiological processes in plants. Cucumis sativus and Cucurbita moschata are important vegetables worldwide. We constructed eight small RNA libraries from leaves and roots of seedlings that were grafted in the following four ways: (1) hetero-grafting, using cucumber as scion and pumpkin as rootstock; (2) hetero-grafting, with pumpkin as scion and cucumber as rootstock; (3) auto-grafting of cucumbers and (4) auto-grafting of pumpkins. High-throughput sequencing was employed, and more than 120 million raw reads were obtained. We annotated 112 known miRNAs belonging to 40 miRNA families and identified 48 new miRNAs in the eight libraries, and the targets of these known and novel miRNAs were predicted by bioinformatics. Grafting led to changes in expression of most miRNAs and their predicted target genes, suggesting that miRNAs may play significant roles in mediating physiological processes of grafted seedlings by regulating the expression of target genes. The potential role of the grafting-responsive miRNAs in seedling growth and long-distance transport of miRNA was discussed. These results are useful for functional characterization of miRNAs in mediation of grafting-dependent physiological processes. PMID:24279842

  13. Adsorption of methyl orange from aqueous solution by aminated pumpkin seed powder: Kinetics, isotherms, and thermodynamic studies.

    PubMed

    Subbaiah, Munagapati Venkata; Kim, Dong-Su

    2016-06-01

    Present research discussed the utilization of aminated pumpkin seed powder (APSP) as an adsorbent for methyl orange (MO) removal from aqueous solution. Batch sorption experiments were carried to evaluate the influence of pH, initial dye concentration, contact time, and temperature. The APSP was characterized by using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The experimental equilibrium adsorption data were fitted using two two-parameter models (Langmuir and Freundlich) and two three-parameter models (Sips and Toth). Langmuir and Sips isotherms provided the best model for MO adsorption data. The maximum monolayer sorption capacity was found to be 200.3mg/g based on the Langmuir isotherm model. The pseudo-first-order and pseudo-second-order model equations were used to analyze the kinetic data of the adsorption process and the data was fitted well with the pseudo-second-order kinetic model (R(2)>0.97). The calculated thermodynamic parameters such as ΔG(0), ΔH(0) and ΔS(0) from experimental data showed that the sorption of MO onto APSP was feasible, spontaneous and endothermic in the temperature range 298-318 K. The FTIR results revealed that amine and carboxyl functional groups present on the surface of APSP. The SEM results show that APSP has an irregular and porous surface which is adequate morphology for dye adsorption. Desorption experiments were carried to explore the feasibility of adsorbent regeneration and the adsorbed MO from APSP was desorbed using 0.1M NaOH with an efficiency of 93.5%. Findings of the present study indicated that APSP can be successfully used for removal of MO from aqueous solution. PMID:26921544

  14. Systemic Induction of NO-, Redox-, and cGMP Signaling in the Pumpkin Extrafascicular Phloem upon Local Leaf Wounding.

    PubMed

    Gaupels, Frank; Furch, Alexandra C U; Zimmermann, Matthias R; Chen, Faxing; Kaever, Volkhard; Buhtz, Anja; Kehr, Julia; Sarioglu, Hakan; Kogel, Karl-Heinz; Durner, Jörg

    2016-01-01

    Cucurbits developed the unique extrafascicular phloem (EFP) as a defensive structure against herbivorous animals. Mechanical leaf injury was previously shown to induce a systemic wound response in the EFP of pumpkin (Cucurbita maxima). Here, we demonstrate that the phloem antioxidant system and protein modifications by NO are strongly regulated during this process. Activities of the central antioxidant enzymes dehydroascorbate reductase, glutathione reductase and ascorbate reductase were rapidly down-regulated at 30 min with a second minimum at 24 h after wounding. As a consequence levels of total ascorbate and glutathione also decreased with similar bi-phasic kinetics. These results hint toward a wound-induced shift in the redox status of the EFP. Nitric oxide (NO) is another important player in stress-induced redox signaling in plants. Therefore, we analyzed NO-dependent protein modifications in the EFP. Six to forty eight hours after leaf damage total S-nitrosothiol content and protein S-nitrosylation were clearly reduced, which was contrasted by a pronounced increase in protein tyrosine nitration. Collectively, these findings suggest that NO-dependent S-nitrosylation turned into peroxynitrite-mediated protein nitration upon a stress-induced redox shift probably involving the accumulation of reactive oxygen species within the EFP. Using the biotin switch assay and anti-nitrotyrosine antibodies we identified 9 candidate S-nitrosylated and 6 candidate tyrosine-nitrated phloem proteins. The wound-responsive Phloem Protein 16-1 (PP16-1) and Cyclophilin 18 (CYP18) as well as the 26.5 kD isoform of Phloem Protein 2 (PP2) were amenable to both NO modifications and could represent important redox-sensors within the cucurbit EFP. We also found that leaf injury triggered the systemic accumulation of cyclic guanosine monophosphate (cGMP) in the EFP and discuss the possible function of this second messenger in systemic NO and redox signaling within the EFP. PMID:26904092

  15. Systemic Induction of NO-, Redox-, and cGMP Signaling in the Pumpkin Extrafascicular Phloem upon Local Leaf Wounding

    PubMed Central

    Gaupels, Frank; Furch, Alexandra C. U.; Zimmermann, Matthias R.; Chen, Faxing; Kaever, Volkhard; Buhtz, Anja; Kehr, Julia; Sarioglu, Hakan; Kogel, Karl-Heinz; Durner, Jörg

    2016-01-01

    Cucurbits developed the unique extrafascicular phloem (EFP) as a defensive structure against herbivorous animals. Mechanical leaf injury was previously shown to induce a systemic wound response in the EFP of pumpkin (Cucurbita maxima). Here, we demonstrate that the phloem antioxidant system and protein modifications by NO are strongly regulated during this process. Activities of the central antioxidant enzymes dehydroascorbate reductase, glutathione reductase and ascorbate reductase were rapidly down-regulated at 30 min with a second minimum at 24 h after wounding. As a consequence levels of total ascorbate and glutathione also decreased with similar bi-phasic kinetics. These results hint toward a wound-induced shift in the redox status of the EFP. Nitric oxide (NO) is another important player in stress-induced redox signaling in plants. Therefore, we analyzed NO-dependent protein modifications in the EFP. Six to forty eight hours after leaf damage total S-nitrosothiol content and protein S-nitrosylation were clearly reduced, which was contrasted by a pronounced increase in protein tyrosine nitration. Collectively, these findings suggest that NO-dependent S-nitrosylation turned into peroxynitrite-mediated protein nitration upon a stress-induced redox shift probably involving the accumulation of reactive oxygen species within the EFP. Using the biotin switch assay and anti-nitrotyrosine antibodies we identified 9 candidate S-nitrosylated and 6 candidate tyrosine-nitrated phloem proteins. The wound-responsive Phloem Protein 16-1 (PP16-1) and Cyclophilin 18 (CYP18) as well as the 26.5 kD isoform of Phloem Protein 2 (PP2) were amenable to both NO modifications and could represent important redox-sensors within the cucurbit EFP. We also found that leaf injury triggered the systemic accumulation of cyclic guanosine monophosphate (cGMP) in the EFP and discuss the possible function of this second messenger in systemic NO and redox signaling within the EFP. PMID:26904092

  16. Impact of high pressure processing on color, bioactive compounds, polyphenol oxidase activity, and microbiological attributes of pumpkin purée.

    PubMed

    González-Cebrino, Francisco; Durán, Rocío; Delgado-Adámez, Jonathan; Contador, Rebeca; Bernabé, Rosario Ramírez

    2016-04-01

    Physicochemical parameters, bioactive compounds' content (carotenoids and total phenols), total antioxidant activity, and enzymatic activity of polyphenol oxidase (PPO) were evaluated after high pressure processing (HPP) on a pumpkin purée (cv. 'Butternut'). Three pressure levels (400, 500, and 600 MPa) were combined with three holding times (200, 400, and 600 s). The applied treatments reduced the levels of total aerobic mesophilic (TAM), total psychrophilic and psychrotrophic bacteria (TPP), and molds and yeasts (M&Y). All applied treatments did not affect enzymatic activity of PPO. Pressure level increased CIE L* values, which could enhance the lightness perception of high pressure (HP)-treated purées. No differences were found between the untreated and HP-treated purées regarding total phenols and carotenoids content (lutein, α-carotene, and β-carotene) and total antioxidant activity. HPP did not affect most quality parameters and maintained the levels of bioactive compounds. However, it did not achieve the complete inhibition of PPO, which could reduce the shelf-life of the pumpkin purée. PMID:26123635

  17. New vitamin E isomers (gamma-tocomonoenol and alpha-tocomonoenol) in seeds, roasted seeds and roasted seed oil from the Slovenian pumpkin variety 'Slovenska golica'.

    PubMed

    Butinar, Bojan; Bučar-Miklavčič, Milena; Mariani, Carlo; Raspor, Peter

    2011-09-15

    The Štajerska region in north-eastern Slovenia and the Styria region in southern Austria have a long tradition of growing pumpkins (Cucurbita pepo L.) as an oil crop. GC-MS determination of the free and esterified minor compounds in oil of roasted pumpkin seeds from the Slovenian C. pepo L. variety 'Slovenska golica' revealed the presence of two previously unreported compounds: alpha-tocomonoenol and gamma-tocomonoenol. Using the GC-MS data, reference samples (Crude Palm Oil) and tocopherol and tocotrienol standards it was possible to assign and quantify alpha-tocomonoenol (17.6±0.6μg/g) and gamma-tocomonoenol (118.7±1.0μg/g) compounds in roasted 'S. golica' seed oil using HPLC. The concentrations of alpha-tocopherol and gamma-tocopherol were 77.9±1.9μg/g and 586.0±4.6μg/g, respectively. Surprisingly the gamma-tocotrienol concentration found was only 6.9±0.2μg/g. Analysis of the seeds from which the oil was pressed showed the initial gamma-tocotrienol amount was even lower (1.6±0.1 and 2.2±0.1μg/g in the ground and roasted seeds, respectively) than in the roasted seed oil. PMID:25212163

  18. Molecular cloning and characterization of a cDNA encoding the gibberellin biosynthetic enzyme ent-kaurene synthase B from pumpkin (Cucurbita maxima L.).

    PubMed

    Yamaguchi, S; Saito, T; Abe, H; Yamane, H; Murofushi, N; Kamiya, Y

    1996-08-01

    The first committed step in the formation of diterpenoids leading to gibberellin (GA) biosynthesis is the conversion of geranylgeranyl diphosphate (GGDP) to ent-kaurene. ent-Kaurene synthase A (KSA) catalyzes the conversion of GGDP to copalyl diphosphate (CDP), which is subsequently converted to ent-kaurene by ent-kaurene synthase B (KSB). A full-length KSB cDNA was isolated from developing cotyledons in immature seeds of pumpkin (Cucurbita maxima L.). Degenerate oligonucleotide primers were designed from the amino acid sequences obtained from the purified protein to amplify a cDNA fragment, which was used for library screening. The isolated full-length cDNA was expressed in Escherichia coli as a fusion protein, which demonstrated the KSB activity to cyclize [3H]CDP to [3H]ent-kaurene. The KSB transcript was most abundant in growing tissues, but was detected in every organ in pumpkin seedlings. The deduced amino acid sequence shares significant homology with other terpene cyclases, including the conserved DDXXD motif, a putative divalent metal ion-diphosphate complex binding site. A putative transit peptide sequence that may target the translated product into the plastids is present in the N-terminal region. PMID:8771778

  19. The effect of stem pruning and nitrogen levels of on some physico-chemical characteristics of pumpkin seed (Cucurbita pepo L.).

    PubMed

    Gholipouri, Abdolghayoum; Nazarnejad, H

    2007-10-15

    To investigate the effects of stem pruning (No heading, head pruning of stem after formation of 10 and 14 nodes) and nitrogen levels (0, 50, 100 and 200 kg ha(-1)) on physical and chemical characteristic of pumpkin seed a Factorial experiment based on randomized complete block design with three replication was carried out in Gorgan at 2003 and repeated in 2004 years. Results showed that the stem pruning has significant effect on traits such as seed oil, linoleic acid and oleic acid content. Nitrogen levels also have significant effect on seed dimension, seed oil, linoleic acid and oleic acid content. The largest amount of oil and linoleic acid content was obtained by stem pruning after forming 14 node and 100 kg ha(-1) nitrogen in separately, but the interaction of treatments were not significant difference for all of traits. PMID:19093491

  20. The Pumpkin Project

    ERIC Educational Resources Information Center

    Hardman, Bonnie

    2005-01-01

    Ms. Hardman's group of special education students were supposed to be "difficult." But their engagement in a novel interdisciplinary project had a transformative effect -- on them, on their teachers, and even on individuals far beyond their school. This article describes children and their experiences in a special education class and how they…

  1. The Pumpkin Problem.

    ERIC Educational Resources Information Center

    Haynes, Charles C.

    1997-01-01

    Halloween is becoming one of the most controversial days of the school year, due to parents' religious, educational, and safety concerns. Although Halloween celebrations do not violate the First Amendment's Establishment Clause, teachers should not use them as an occasion to teach about Druidism. Schools should have opt-out provisions and…

  2. Effect of oil extraction assisted by ultrasound on the physicochemical properties and fatty acid profile of pumpkin seed oil (Cucurbita pepo).

    PubMed

    Hernández-Santos, Betsabé; Rodríguez-Miranda, Jesús; Herman-Lara, Erasmo; Torruco-Uco, Juan G; Carmona-García, Roselis; Juárez-Barrientos, José M; Chávez-Zamudio, Rubí; Martínez-Sánchez, Cecilia E

    2016-07-01

    The effects of amplitude and time of ultrasound-assisted extraction on the physicochemical properties and the fatty acid profile of pumpkin seed oil (Cucurbita pepo) were evaluated. Ultrasound time (5-30 min) and the response variables amplitude (25-100%), extraction yield, efficiency, oxidative stability in terms of the free fatty acids (FFA) of the plant design comprising two independent experiments variables, peroxide (PV), p-anisidine (AV), totox value (TV) and the fatty acid profile were evaluated. The results were analyzed by multiple linear regression. The time and amplitude showed significant differences (P<0.05) for all variables. The highest yield of extraction was achieved at 5 min and amplitude of 62.5% (62%). However, the optimal ultrasound-assisted extraction conditions were as follows: ultrasound time of 26.34 min and amplitude of 89.02%. All extracts showed low FFA (2.75-4.93% oleic acid), PV (1.67-4.68 meq/kg), AV (1.94-3.69) and TV (6.25-12.55) values. The main fatty acids in all the extracts were oleic and linoleic acid. Therefore, ultrasound-assisted oil extraction had increased performance and reduced extraction time without affecting the oil quality. PMID:26964969

  3. Effect of pumpkin seed oil on hair growth in men with androgenetic alopecia: a randomized, double-blind, placebo-controlled trial.

    PubMed

    Cho, Young Hye; Lee, Sang Yeoup; Jeong, Dong Wook; Choi, Eun Jung; Kim, Yun Jin; Lee, Jeong Gyu; Yi, Yu Hyeon; Cha, Hyeong Soo

    2014-01-01

    Pumpkin seed oil (PSO) has been shown to block the action of 5-alpha reductase and to have antiandrogenic effects on rats. This randomized, placebo-controlled, double-blind study was designed to investigate the efficacy and tolerability of PSO for treatment of hair growth in male patients with mild to moderate androgenetic alopecia (AGA). 76 male patients with AGA received 400 mg of PSO per day or a placebo for 24 weeks. Change over time in scalp hair growth was evaluated by four outcomes: assessment of standardized clinical photographs by a blinded investigator; patient self-assessment scores; scalp hair thickness; and scalp hair counts. Reports of adverse events were collected throughout the study. After 24 weeks of treatment, self-rated improvement score and self-rated satisfaction scores in the PSO-treated group were higher than in the placebo group (P = 0.013, 0.003). The PSO-treated group had more hair after treatment than at baseline, compared to the placebo group (P < 0.001). Mean hair count increases of 40% were observed in PSO-treated men at 24 weeks, whereas increases of 10% were observed in placebo-treated men (P < 0.001). Adverse effects were not different in the two groups. PMID:24864154

  4. Supplementation with pumpkin seed oil improves plasma lipid profile and cardiovascular outcomes of female non-ovariectomized and ovariectomized Sprague-Dawley rats.

    PubMed

    Gossell-Williams, M; Lyttle, K; Clarke, T; Gardner, M; Simon, O

    2008-07-01

    Pumpkin (Cucurbita species) seed oil (PSO) is a rich source of phytoestrogens and the aim of this study was to examine the effect of PSO supplementation on the total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), triglycerides, high density lipoprotein cholesterol (HDL-C), systolic and diastolic blood pressure in non-ovariectomized and ovariectomized Sprague-Dawley rats. Female rats weighing 220-300 g were divided into non-ovariectomized rats for supplementation with corn oil (control CO; n = 6) or PSO (control PSO; n = 5) and ovariectomized rats for supplementation with corn oil (OVX/CO; n = 6) or PSO (OVX/PSO; n = 5) for 5 days per week for 12 weeks (corn oil 40 mg/kg or PSO 40 mg/kg given orally). Systolic and diastolic blood pressures were measured weekly. Blood was collected at the end of the period for plasma lipid assays. Control PSO had lower TC, LDL-C, triglycerides and higher HDL-C than the control CO. The OVX/CO had higher TC, LDL-C, triglycerides and lower HDL-C than the control CO and these changes were prevented in the OVX/PSO rats. PSO supplementation also resulted in lower systolic and diastolic blood pressures in both non-ovariectomized and ovariectomized rats. It is concluded that PSO supplementation can prevent changes in plasma lipids and blood pressure associated with inadequate oestrogen availability. PMID:18567058

  5. Analysis of gamma-irradiated melon, pumpkin, and sunflower seeds by electron paramagnetic resonance spectroscopy and gas chromatography-mass spectrometry.

    PubMed

    Sin, Della W M; Wong, Yiu Chung; Yao, Wai Yin

    2006-09-20

    Seeds of melon (Citrullus lanatus var. sp.), pumpkin (Cucurbita moschata), and sunflower (Heliantus annus) were gamma-irradiated at 1, 3, 5, and 10 kGy and analyzed by electron paramagnetic resonance (EPR) and gas chromatography-mass spectrometry (GC-MS) according to EN1787:2000 and EN1785:2003, respectively. Distinguishable triplet signals due to the presence of induced cellulose radicals were found at 2.0010-2.0047 g in the EPR spectra. The gamma-irradiated radiolytic markers of 2-dodecylcyclobutanone (2-DCB) and 2-tetradecylcyclobutanone (2-TCB) were identified in all irradiated seed samples. Both the free radicals and the alkylcyclobutanones were found to increase with irradiation dose. In general, linear relationships between the amount of radicals and irradiation dosage could be established. Studies at an ambient temperature (20-25 degrees C) in a humidity-controlled environment showed a complete disappearance of the cellulosic peaks for irradiated samples upon 60 days of storage. Such instability behavior was considered to render the usefulness of using EPR alone in the determination of irradiated seed samples. On the other hand, 2-DCB and 2-TCB were also found to decompose rapidly (>85% loss after 120 days of storage), but the radiolytic markers remained quantifiable after 120 days of postirradiation storage. These results suggest that GC-MS is a versatile and complimentary technique for the confirmation of irradiation treatment to seeds. PMID:16968077

  6. Slow Degradation of the D1 Protein Is Related to the Susceptibility of Low-Light-Grown Pumpkin Plants to Photoinhibition 1

    PubMed Central

    Tyystjärvi, Esa; Ali-Yrkkö, Kati; Kettunen, Reetta; Aro, Eva-Mari

    1992-01-01

    Photoinhibition of photosystem II (PSII) electron transport and subsequent degradation of the D1 protein were studied in pumpkin (Cucurbita pepo L.) leaves developed under high (1000 μmol m−2 s−1) and low (80 μmol m−2 s−1) photon flux densities. The low-light leaves were more susceptible to high light. This difference was greatly diminished when illumination was performed in the presence of chloramphenicol, indicating that a poor capacity to repair photodamaged PSII centers is decisive in the susceptibility of low-light leaves to photoinhibition. In fact, the first phases of the repair cycle, degradation and removal of photodamaged D1 protein from the reaction center complex, occurred slowly in low-light leaves, whereas in high-light leaves the degradation of the D1 protein more readily followed photoinhibition of PSII electron transport. A modified form of the D1 protein, with slightly slower electrophoretic mobility than the original D1, accumulated in the appressed thylakoid membranes of low-light leaves during illumination and was subsequently degraded only slowly. Images Figure 6 Figure 8 PMID:16653122

  7. Effect of Pumpkin Seed Oil on Hair Growth in Men with Androgenetic Alopecia: A Randomized, Double-Blind, Placebo-Controlled Trial

    PubMed Central

    Jeong, Dong Wook; Choi, Eun Jung; Kim, Yun Jin; Lee, Jeong Gyu; Yi, Yu Hyeon; Cha, Hyeong Soo

    2014-01-01

    Pumpkin seed oil (PSO) has been shown to block the action of 5-alpha reductase and to have antiandrogenic effects on rats. This randomized, placebo-controlled, double-blind study was designed to investigate the efficacy and tolerability of PSO for treatment of hair growth in male patients with mild to moderate androgenetic alopecia (AGA). 76 male patients with AGA received 400 mg of PSO per day or a placebo for 24 weeks. Change over time in scalp hair growth was evaluated by four outcomes: assessment of standardized clinical photographs by a blinded investigator; patient self-assessment scores; scalp hair thickness; and scalp hair counts. Reports of adverse events were collected throughout the study. After 24 weeks of treatment, self-rated improvement score and self-rated satisfaction scores in the PSO-treated group were higher than in the placebo group (P = 0.013, 0.003). The PSO-treated group had more hair after treatment than at baseline, compared to the placebo group (P < 0.001). Mean hair count increases of 40% were observed in PSO-treated men at 24 weeks, whereas increases of 10% were observed in placebo-treated men (P < 0.001). Adverse effects were not different in the two groups. PMID:24864154

  8. Saccharification of pumpkin residues by coculturing of Trichoderma reesei RUT-C30 and Phanerochaete chrysosporium Burdsall with delayed inoculation timing.

    PubMed

    Yang, Rui; Meng, Demei; Hu, Xiaosong; Ni, Yuanying; Li, Quanhong

    2013-09-25

    Trichoderma reesei and Phanerochaete chrysosporium with different lignocellulose-degrading enzyme systems have received much attention due to their ability to biodegrade lignocellulosic biomass. However, the synergistic effect of the two fungi on lignocellulose degradation is unknown. Herein, a cocultivation of T. reesei RUT-C30 and P. chrysosporium Burdsall for biodegradation of lignocellulosic pumpkin residues (PRS) was developed to produce soluble saccharide. Results indicated that a cocultivation of the two fungi with P. chrysosporium Burdsall inoculation delayed for 1.5 days produced the highest saccharide yield of 53.08% (w/w), and only 20.83% (w/w) of PRS were left after one batch of fermentation. In addition, this strategy increased the activities of secreted cellulases (endoglucanase, cellobiohydrolase, and β-glucosidase) and ligninases (lignin peroxidase and manganese peroxidase), which correlated to the increased saccharide yield. Besides, the resulting monosaccharides including glucose (1.23 mg/mL), xylose (0.13 mg/mL), arabinose (0.46 mg/mL), and fructose (0.21 mg/mL) from cocultures exhibited much higher yields than those from monoculture, which provides basal information for further fermentation research. This bioconversion of PRS into soluble sugars by cocultured fungal species provides a low cost method based on lignocellulose for potential biofuels or other bioproduct production. PMID:24020787

  9. Aspen Tension Wood Fibers Contain β-(1→4)-Galactans and Acidic Arabinogalactans Retained by Cellulose Microfibrils in Gelatinous Walls1[OPEN

    PubMed Central

    Gorshkova, Tatyana; Mokshina, Natalia; Chernova, Tatyana; Ibragimova, Nadezhda; Salnikov, Vadim; Mikshina, Polina; Tryfona, Theodora; Banasiak, Alicja; Immerzeel, Peter; Dupree, Paul; Mellerowicz, Ewa J.

    2015-01-01

    Contractile cell walls are found in various plant organs and tissues such as tendrils, contractile roots, and tension wood. The tension-generating mechanism is not known but is thought to involve special cell wall architecture. We previously postulated that tension could result from the entrapment of certain matrix polymers within cellulose microfibrils. As reported here, this hypothesis was corroborated by sequential extraction and analysis of cell wall polymers that are retained by cellulose microfibrils in tension wood and normal wood of hybrid aspen (Populus tremula × Populus tremuloides). β-(1→4)-Galactan and type II arabinogalactan were the main large matrix polymers retained by cellulose microfibrils that were specifically found in tension wood. Xyloglucan was detected mostly in oligomeric form in the alkali-labile fraction and was enriched in tension wood. β-(1→4)-Galactan and rhamnogalacturonan I backbone epitopes were localized in the gelatinous cell wall layer. Type II arabinogalactans retained by cellulose microfibrils had a higher content of (methyl)glucuronic acid and galactose in tension wood than in normal wood. Thus, β-(1→4)-galactan and a specialized form of type II arabinogalactan are trapped by cellulose microfibrils specifically in tension wood and, thus, are the main candidate polymers for the generation of tensional stresses by the entrapment mechanism. We also found high β-galactosidase activity accompanying tension wood differentiation and propose a testable hypothesis that such activity might regulate galactan entrapment and, thus, mechanical properties of cell walls in tension wood. PMID:26378099

  10. Replacement of Dietary Saturated Fat by PUFA-Rich Pumpkin Seed Oil Attenuates Non-Alcoholic Fatty Liver Disease and Atherosclerosis Development, with Additional Health Effects of Virgin over Refined Oil

    PubMed Central

    Morrison, Martine C.; Mulder, Petra; Stavro, P. Mark; Suárez, Manuel; Arola-Arnal, Anna; van Duyvenvoorde, Wim; Kooistra, Teake; Wielinga, Peter Y.; Kleemann, Robert

    2015-01-01

    Background and Aims As dietary saturated fatty acids are associated with metabolic and cardiovascular disease, a potentially interesting strategy to reduce disease risk is modification of the quality of fat consumed. Vegetable oils represent an attractive target for intervention, as they largely determine the intake of dietary fats. Furthermore, besides potential health effects conferred by the type of fatty acids in a vegetable oil, other minor components (e.g. phytochemicals) may also have health benefits. Here, we investigated the potential long-term health effects of isocaloric substitution of dietary fat (i.e. partial replacement of saturated by unsaturated fats), as well as putative additional effects of phytochemicals present in unrefined (virgin) oil on development of non-alcoholic fatty liver disease (NAFLD) and associated atherosclerosis. For this, we used pumpkin seed oil, because it is high in unsaturated fatty acids and a rich source of phytochemicals. Methods ApoE*3Leiden mice were fed a Western-type diet (CON) containing cocoa butter (15% w/w) and cholesterol (1% w/w) for 20 weeks to induce risk factors and disease endpoints. In separate groups, cocoa butter was replaced by refined (REF) or virgin (VIR) pumpkin seed oil (comparable in fatty acid composition, but different in phytochemical content). Results Both oils improved dyslipidaemia, with decreased (V)LDL-cholesterol and triglyceride levels in comparison with CON, and additional cholesterol-lowering effects of VIR over REF. While REF did not affect plasma inflammatory markers, VIR reduced circulating serum amyloid A and soluble vascular adhesion molecule-1. NAFLD and atherosclerosis development was modestly reduced in REF, and VIR strongly decreased liver steatosis and inflammation as well as atherosclerotic lesion area and severity. Conclusions Overall, we show that an isocaloric switch from a diet rich in saturated fat to a diet rich in unsaturated fat can attenuate NAFLD and atherosclerosis

  11. Growing Pumpkins Where Missiles Grew

    ERIC Educational Resources Information Center

    Loret, John

    1976-01-01

    Purposes of transforming the former Nike-Ajax missile base into a living historical homestead environmental center, resembling an 1800 Long Island village, were to build a homestead environmental center and develop materials, using homestead and pioneer skills, that could be used for education and recreation programs for the schools and community.…

  12. The Evaluation of Dipeptidyl Peptidase (DPP)-IV, α-Glucosidase and Angiotensin Converting Enzyme (ACE) Inhibitory Activities of Whey Proteins Hydrolyzed with Serine Protease Isolated from Asian Pumpkin (Cucurbita ficifolia).

    PubMed

    Konrad, Babij; Anna, Dąbrowska; Marek, Szołtysik; Marta, Pokora; Aleksandra, Zambrowicz; Józefa, Chrzanowska

    2014-01-01

    In the present study, whey protein concentrate (WPC-80) and β-lactoglobulin were hydrolyzed with a noncommercial serine protease isolated from Asian pumpkin (Cucurbita ficifolia). Hydrolysates were further fractionated by ultrafiltration using membranes with cut-offs equal 3 and 10 kDa. Peptide fractions of molecular weight lower than 3 and 3-10 kDa were further subjected to the RP-HPLC. Separated preparations were investigated for their potential as the natural inhibitors of dipeptidyl peptidase (DPP-IV), α-glucosidase and angiotensin converting enzyme (ACE). WPC-80 hydrolysate showed higher inhibitory activities against the three tested enzymes than β-lactoglobulin hydrolysate. Especially high biological activities were exhibited by peptide fractions of molecular weight lower than 3 kDa, with ACE IC50 <0.64 mg/mL and DPP-IV IC50 <0.55 mg/mL. This study suggests that peptides generated from whey proteins may support postprandial glycemia regulation and blood pressure maintenance, and could be used as functional food ingredients in the diet of patients with type 2 diabetes. PMID:25364320

  13. Cucurbits [Cucumber, melon, pumpkin and squash

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The focus of this chapter is on the edible members of the Cucurbitaceae family. The three important food-grade cucurbit genera Citrullus, Cucumis, and Cucurbita include the species Citrullus lanatus watermelons), Cucumis melo (cantaloupes and other sweet melons), Cucumis sativa (cucumbers and pick...

  14. Pilgrims, Pumpkins, and Turkeys: A Thanksgiving Bounty!!!

    ERIC Educational Resources Information Center

    Byerly, Greg; Brodie, Carolyn S.

    1999-01-01

    Describes several Thanksgiving Web sites, including those with historical information, favorite Thanksgiving foods and recipes, songs and games, arts and crafts activities, and some sites "just for fun." Sites include everything from the Macy's Day Parade site, to PlimothonWeb, to Thanksgiving clip art. (AEF)

  15. Conquering the Pumpkin Effect: A Lighting Alternative.

    ERIC Educational Resources Information Center

    Stanley, Gary B.

    1993-01-01

    Turning off all the interior and exterior lighting when school buildings are closed saves money. In a small Illinois school district, nearly $14,000 were saved in electrical expenditures for six buildings. Another Illinois district currently has 19 of its 32 buildings blacked out at night and saves over $150,000 annually. Vandalism and loitering…

  16. Hysteroscopic training: the butternut pumpkin model.

    PubMed

    Kingston, Ashley; Abbott, Jason; Lenart, Meg; Vancaillie, Thierry

    2004-05-01

    Operative hysteroscopy involves significant hand-eye coordination, utilizing energy sources, video imaging, and the safe control of distending media. We describe a safe, effective, inexpensive, and reproducible method of developing the skills and hand-eye coordination for diagnostic and operative hysteroscopy. In this inanimate model, advanced surgical skills can be practiced, and realistic, simulated electrosurgery including resection of the endometrium and rollerball ablation can be performed. PMID:15200786

  17. cDNA cloning and gene expression of ascorbate oxidase in tobacco.

    PubMed

    Kato, N; Esaka, M

    1996-02-01

    A cDNA clone for ascorbate oxidase (AAO) has been isolated from a cDNA library of tobacco (Nicotiana tabacum) cells. The identity of the amino acid sequence deduced from tobacco AAO cDNA to that from pumpkin AAO cDNA was 68%, which was much lower than the identity (80%) between pumpkin and cucumber AAO. AAO activity in tobacco cells was much lower than that in pumpkin cells, whereas the immunoreactive protein in tobacco cells was more abundant than that in pumpkin cells. We suppose that AAO protein in tobacco cells may be less active than that in pumpkin cells. Genomic Southern blotting suggested that AAO in tobacco was encoded by a single-copy gene. Nothern blotting revealed that mRNA of AAO was highly expressed in young and growing tissues of tobacco plant. PMID:8624413

  18. Suppression of growth and invasive behavior of human prostate cancer cells by ProstaCaid™: mechanism of activity.

    PubMed

    Jiang, Jiahua; Eliaz, Isaac; Sliva, Daniel

    2011-06-01

    Since the use of dietary supplements as alternative treatments or adjuvant therapies in cancer treatment is growing, a scientific verification of their biological activity and the detailed mechanisms of their action are necessary for the acceptance of dietary supplements in conventional cancer treatments. In the present study we have evaluated the anti-cancer effects of dietary supplement ProstaCaid™ (PC) which contains mycelium from medicinal mushrooms (Ganoderma lucidum, Coriolus versicolor, Phellinus linteus), saw palmetto berry, pomegranate, pumpkin seed, green tea [40% epigallocatechin-3-gallate (EGCG)], Japanese knotweed (50% resveratrol), extracts of turmeric root (BCM-95®), grape skin, pygeum bark, sarsaparilla root, Scutellaria barbata, eleuthero root, Job's tears, astragalus root, skullcap, dandelion, coptis root, broccoli, and stinging nettle, with purified vitamin C, vitamin D3, selenium, quercetin, citrus bioflavonoid complex, β sitosterolzinc, lycopene, α lipoic acid, boron, berberine and 3.3'-diinodolymethane (DIM). We show that PC treatment resulted in the inhibition of cell proliferation of the highly invasive human hormone refractory (independent) PC-3 prostate cancer cells in a dose- and time-dependent manner with IC50 56.0, 45.6 and 39.0 µg/ml for 24, 48 and 72 h, respectively. DNA-microarray analysis demonstrated that PC inhibits proliferation through the modulation of expression of CCND1, CDK4, CDKN1A, E2F1, MAPK6 and PCNA genes. In addition, PC also suppresses metastatic behavior of PC-3 by the inhibition of cell adhesion, cell migration and cell invasion, which was associated with the down-regulation of expression of CAV1, IGF2, NR2F1, and PLAU genes and suppressed secretion of the urokinase plasminogen activator (uPA) from PC-3 cells. In conclusion, the dietary supplement PC is a promising natural complex with the potency to inhibit invasive human prostate cancer. PMID:21468543

  19. Stem Cells

    MedlinePlus

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  20. Cell Structure

    MedlinePlus

    ... Cells, Tissues, & Membranes Cell Structure & Function Cell Structure Cell Function Body Tissues Epithelial Tissue Connective Tissue Muscle Tissue ... apparatus , and lysosomes . « Previous (Cell Structure & Function) Next (Cell Function) » Contact Us | Privacy Policy | Accessibility | FOIA | File Formats ...

  1. Stem Cells

    MedlinePlus

    Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  2. Research Report. Circle Time-Getting Past "Two Little Pumpkins."

    ERIC Educational Resources Information Center

    McAfee, Oralie D.

    1985-01-01

    Reports results of a study in which 35 teachers of children ages 2.5 through kindergarten were interviewed and observed during group time. Reveals tentative conclusions that teachers can plan and implement activities that are more appropriate to the age, developmental level, or social functioning of the group. Offers specific recommendations for…

  3. Genes for resistance to zucchini yellow mosaic in tropical pumpkin.

    PubMed

    Pachner, Martin; Paris, Harry S; Lelley, Tamas

    2011-01-01

    Four cultigens of Cucurbita moschata resistant to zucchini yellow mosaic virus were crossed with the susceptible 'Waltham Butternut' and with each other in order to clarify the mode of inheritance of resistance and relationships among the genes involved. Five loci were segregating, with genes for resistance Zym-0 and Zym-4 carried by 'Nigerian Local' and one of them also carried by 'Nicklow's Delight,' Zym-1 carried by 'Menina,' and zym-6 carried by 'Soler.' A recessive gene carried by 'Waltham Butternut,' zym-5, is complementary with the dominant Zym-4 of 'Nigerian Local,' that is, the resistance conferred by Zym-4 is only expressed in zym-5/zym-5 individuals. Gene zym-6 appears to be linked to either Zym-0 or Zym-4, and it is also possible that Zym-1 is linked to one of them as well. PMID:21493595

  4. T Cells

    MedlinePlus

    ... or turn off the immune response. Cytotoxic or “killer” T cells directly attack and destroy cells bearing ... involve selective activation of helper T cells and killer T cells, with a corresponding decrease in regulatory ...

  5. Cell division

    MedlinePlus Videos and Cool Tools

    ... hours after conception, the fertilized egg cell remains a single cell. After approximately 30 hours, it divides ... 3 days, the fertilized egg cell has become a berry-like structure made up of 16 cells. ...

  6. Cell counting.

    PubMed

    Phelan, M C; Lawler, G

    2001-05-01

    This unit presents protocols for counting cells using either a hemacytometer or electronically using a Coulter counter. Cell counting with a hemacytometer permits effective discrimination of live from dead cells using trypan blue exclusion. In addition, the procedure is less subject to errors arising from cell clumping or size heterogeneity. Counting cells is more quickly and easily performed using an electronic counter, but live-dead discrimination is unreliable. Cell populations containing large numbers of dead cells and/or cell clumps are difficult to count accurately. In addition, electronic counting requires resetting of the instrument for cell populations of different sizes; heterogeneous populations can give rise to inaccurate counts, and resting and activated cells may require counting at separate settings. In general, electronic cell counting is best performed on fresh peripheral blood cells. PMID:18770655

  7. Galvanic Cells

    ERIC Educational Resources Information Center

    Young, I. G.

    1973-01-01

    Many standard physical chemistry textbooks contain ambiguities which lead to confusion about standard electrode potentials, calculating cell voltages, and writing reactions for galvanic cells. This article shows how standard electrode potentials can be used to calculate cell voltages and deduce cell reactions. (Author/RH)

  8. Cell Biochips

    NASA Astrophysics Data System (ADS)

    Pioufle, B. Le; Picollet-D'Hahan, N.

    A cell biochip is a microsystem, equipped with electronic and microfluidic functions, designed to manipulate or analyse living cells. The first publications in this emerging area of research appeared toward the end of the 1980s. In 1989 Washizu described a biochip designed to fuse two cells by electropermeabilisation of the cytoplasmic membrane [1]. Research centers have devised a whole range of cell chip structures, for simultaneous or sequential analysis of single cells, cell groups, or cell tissues reconstituted on the chip. The cells are arranged in a square array on a parallel cell chip for parallel analysis, while they are examined and processed one by one in a microchannel in the case of a series cell chip. In contrast to these biochips for high-throughput analysis of a large number of cells, single-cell chips focus on the analysis of a single isolated cell. As in DNA microarrays, where a large number of oligonucleotides are ordered in a matrix array, parallel cell chips order living cells in a similar way. At each point of the array, the cells can be isolated, provided that the cell type allows this, e.g., blood cells, or cultivated in groups (most adhesion cells can only survive in groups). The aim is to allow massively parallel analysis or processing. Le Pioufle et al. describe a microdevice for the culture of single cells or small groups of cells in a micropit array [2]. Each pit is equipped to stimulate the cell or group of cells either electrically or fluidically. Among the applications envisaged are gene transfer, cell sorting, and screening in pharmacology. A complementary approach, combining the DNA microarray and cell biochip ideas, has been put forward by Bailey et al. [3]. Genes previously arrayed on the chip transfect the cultured cells on the substrate depending on their position in the array (see Fig. 19.1). This way of achieving differential lipofection on a chip was then taken up again by Yoshikawa et al. [4] with primary cells, more

  9. Cell division

    MedlinePlus Videos and Cool Tools

    ... structure made up of 16 cells. This structure is called a morula, which is Latin for mulberry. The cells continue to divide ... days following conception into a blastocyst. Although it is only the size of a pinhead, the blastocyst ...

  10. Solar cells

    NASA Astrophysics Data System (ADS)

    Cuquel, A.; Roussel, M.

    The physical and electronic characteristics of solar cells are discussed in terms of space applications. The principles underlying the photovoltaic effect are reviewed, including an analytic model for predicting the performance of individual cells and arrays of cells. Attention is given to the effects of electromagnetic and ionizing radiation, micrometeors, thermal and mechanical stresses, pollution and degassing encountered in space. The responses of different types of solar cells to the various performance-degrading agents are examined, with emphasis on techniques for quality assurance in the manufacture and mounting of Si cells.

  11. Types of Stem Cells

    MedlinePlus

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... stem cells blog from the International Society for Stem Cell Research. Learn About Stem Cells From Lab to You ...

  12. Electrolytic cell

    NASA Astrophysics Data System (ADS)

    Bullock, J. S.; Hale, B. D.

    1984-09-01

    An apparatus is described for the separation of the anolyte and the catholyte during electrolysis. The electrolyte flows through an electrolytic cell between the oppositely charged electrodes. The cell is equipped with a wedge-shaped device, the tapered end is located between the electrodes on the effluent side of the cell. The wedge diverts the flow of the electrolyte to either side of the wedge, substantially separating the anolyte and the catholyte.

  13. Cell Chauvinism

    ERIC Educational Resources Information Center

    Keller, Dolores Elaine

    1972-01-01

    Indicates that biological terminology, such as mother cell'' and labels of sex factors in bacteria, reflect discrimination against females by reinforcing perpetuation of stereotyped gender roles. (AL)

  14. Cell migration.

    PubMed

    Trepat, Xavier; Chen, Zaozao; Jacobson, Ken

    2012-10-01

    Cell migration is fundamental to establishing and maintaining the proper organization of multicellular organisms. Morphogenesis can be viewed as a consequence, in part, of cell locomotion, from large-scale migrations of epithelial sheets during gastrulation, to the movement of individual cells during development of the nervous system. In an adult organism, cell migration is essential for proper immune response, wound repair, and tissue homeostasis, while aberrant cell migration is found in various pathologies. Indeed, as our knowledge of migration increases, we can look forward to, for example, abating the spread of highly malignant cancer cells, retarding the invasion of white cells in the inflammatory process, or enhancing the healing of wounds. This article is organized in two main sections. The first section is devoted to the single-cell migrating in isolation such as occurs when leukocytes migrate during the immune response or when fibroblasts squeeze through connective tissue. The second section is devoted to cells collectively migrating as part of multicellular clusters or sheets. This second type of migration is prevalent in development, wound healing, and in some forms of cancer metastasis. PMID:23720251

  15. Cell Migration

    PubMed Central

    Trepat, Xavier; Chen, Zaozao; Jacobson, Ken

    2015-01-01

    Cell migration is fundamental to establishing and maintaining the proper organization of multicellular organisms. Morphogenesis can be viewed as a consequence, in part, of cell locomotion, from large-scale migrations of epithelial sheets during gastrulation, to the movement of individual cells during development of the nervous system. In an adult organism, cell migration is essential for proper immune response, wound repair, and tissue homeostasis, while aberrant cell migration is found in various pathologies. Indeed, as our knowledge of migration increases, we can look forward to, for example, abating the spread of highly malignant cancer cells, retarding the invasion of white cells in the inflammatory process, or enhancing the healing of wounds. This article is organized in two main sections. The first section is devoted to the single-cell migrating in isolation such as occurs when leukocytes migrate during the immune response or when fibroblasts squeeze through connective tissue. The second section is devoted to cells collectively migrating as part of multicellular clusters or sheets. This second type of migration is prevalent in development, wound healing, and in some forms of cancer metastasis. PMID:23720251

  16. Cell Trivision of Hyperploid Cells

    PubMed Central

    Nagy, Gabor; Kiraly, Gabor; Turani, Melinda

    2013-01-01

    Malignant transformation is likely to render cells hyperploid, primarily tetraploid. We have measured the frequency of division into three rather than two daughter cells as a function of ploidy. Such trivisions were followed in near-tetraploid uveal melanoma (UM), hypotetraploid HaCaT (<4 N), hypertriploid HeLa (>3 N), and in near-diploid (∼2 N) lung epithelial cell lines by time-lapse image analyses. A stepwise analysis of cytokinesis revealed higher frequency of cell trivisions relative to divisions in hyperploid HeLa (1:24, 4%), HaCaT (1:126, 8%), and UM (1:186, 0.5%) cells. The occurrence of trivision was significantly lower in near-diploid endothelial cells (1:1400, 0.07%). We have previously observed the phenomenon of trivision in HaCaT cells treated with heavy metal lead, and here we describe that trivision is a spontaneous process taking place without genotoxic treatment. Beside re-diploidization by trivision, the hyperploid state decreases the cell size of the daughter cells and is likely to increase the time of cytokinesis. On the basis of the results, it is hypothesized that among other cancer-related causes, hyperploidy could be related to cell trivision, could cause random aneuploidy, and could generate new cancer-specific karyotypes. PMID:24093497

  17. Photovoltaic cell

    SciTech Connect

    Bronstein-Bonte, I.Y.; Fischer, A.B.

    1986-12-16

    This patent describes a product comprising a photovoltaic cell including a luminescent dye which will absorb radiation at a wavelength to which the cell is not significantly responsive and emit radiation at a higher wavelength at which it is responsive. The improvement described here is wherein the dye comprises a lepidopterene.

  18. Fuel Cells

    ERIC Educational Resources Information Center

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  19. Cell Lines

    PubMed Central

    Cherbas, Lucy; Gong, Lei

    2014-01-01

    We review the properties and uses of cell lines in Drosophila research, emphasizing the variety of lines, the large body of genomic and transcriptional data available for many of the lines, and the variety of ways the lines have been used to provide tools for and insights into the developmental, molecular, and cell biology of Drosophila and mammals. PMID:24434506

  20. Host cells and cell banking.

    PubMed

    Stacey, Glyn N; Merten, Otto-Wilhelm

    2011-01-01

    Gene therapy based on the use of viral vectors is entirely dependent on the use of animal cell lines, mainly of mammalian origin, but also of insect origin. As for any biotechnology product for clinical use, viral -vectors have to be produced with cells derived from an extensively characterized cell bank to maintain the appropriate standard for assuring the lowest risk for the patients to be treated. Although many different cell types and lines have been used for the production of viral vectors, HEK293 cells or their derivatives have been extensively used for production of different vector types: adenovirus, oncorectrovirus, lentivirus, and AAV vectors, because of their easy handling and the possibility to grow them adherently in serum-containing medium as well as in suspension in serum-free culture medium. Despite this, these cells are not necessarily the best for the production of a given viral vector, and there are many other cell lines with significant advantages including superior growth and/or production characteristics, which have been tested and also used for the production of clinical vector batches. This chapter presents basic -considerations concerning the characterization of cell banks, in the first part, and, in the second part, practically all cell lines (at least when public information was available) established and developed for the production of the most important viral vectors (adenoviral, oncoretroviral, lentiviral, AAV, baculovirus). PMID:21590393

  1. Fuel cells 101

    SciTech Connect

    Hirschenhofer, J.H.

    1999-07-01

    This paper discusses the various types of fuel cells, the importance of cell voltage, fuel processing for natural gas, cell stacking, fuel cell plant description, advantages and disadvantages of the types of fuel cells, and applications. The types covered include: polymer electrolyte fuel cell, alkaline fuel cell, phosphoric acid fuel cell; molten carbonate fuel cell, and solid oxide fuel cell.

  2. Cell polarity

    PubMed Central

    Romereim, Sarah M

    2011-01-01

    Despite extensive genetic analysis of the dynamic multi-phase process that transforms a small population of lateral plate mesoderm into the mature limb skeleton, the mechanisms by which signaling pathways regulate cellular behaviors to generate morphogenetic forces are not known. Recently, a series of papers have offered the intriguing possibility that regulated cell polarity fine-tunes the morphogenetic process via orienting cell axes, division planes and cell movements. Wnt5a-mediated non-canonical signaling, which may include planar cell polarity, has emerged as a common thread in the otherwise distinct signaling networks that regulate morphogenesis in each phase of limb development. These findings position the limb as a key model to elucidate how global tissue patterning pathways direct local differences in cell behavior that, in turn, generate growth and form. PMID:22064549

  3. 7 CFR 301.32-2 - Regulated articles.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... utilissimus Melon, long Peach. Cucurbita maxima Squash Melon. Cucurbita moschata Pumpkin, Canada Melon. Cucurbita pepo Pumpkin Melon. Cydonia oblonga Quince Mexican, Mediterranean, Oriental, Peach, Sapote... (Cucumis utilissimus) Pumpkin (Cucurbita pepo) Pumpkin, Canada (Cucurbita moschata) Squash...

  4. 7 CFR 301.32-2 - Regulated articles.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... utilissimus Melon, long Peach. Cucurbita maxima Squash Melon. Cucurbita moschata Pumpkin, Canada Melon. Cucurbita pepo Pumpkin Melon. Cydonia oblonga Quince Mexican, Mediterranean, Oriental, Peach, Sapote... (Cucumis utilissimus) Pumpkin (Cucurbita pepo) Pumpkin, Canada (Cucurbita moschata) Squash...

  5. 7 CFR 301.32-2 - Regulated articles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... utilissimus Melon, long Peach. Cucurbita maxima Squash Melon. Cucurbita moschata Pumpkin, Canada Melon. Cucurbita pepo Pumpkin Melon. Cydonia oblonga Quince Mexican, Mediterranean, Oriental, Peach, Sapote... (Cucumis utilissimus) Pumpkin (Cucurbita pepo) Pumpkin, Canada (Cucurbita moschata) Squash...

  6. 7 CFR 301.32-2 - Regulated articles.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... utilissimus Melon, long Peach. Cucurbita maxima Squash Melon. Cucurbita moschata Pumpkin, Canada Melon. Cucurbita pepo Pumpkin Melon. Cydonia oblonga Quince Mexican, Mediterranean, Oriental, Peach, Sapote... (Cucumis utilissimus) Pumpkin (Cucurbita pepo) Pumpkin, Canada (Cucurbita moschata) Squash...

  7. Neurospora crassa 1,3-α-glucan synthase, AGS-1, is required for cell wall biosynthesis during macroconidia development

    PubMed Central

    Fu, Ci; Tanaka, Asuma

    2014-01-01

    The Neurospora crassa genome encodes two 1,3-α-glucan synthases. One of these 1,3-α-glucan synthase genes, ags-1, was shown to be required for the synthesis of 1,3-α-glucan in the aerial hyphae and macroconidia cell walls. 1,3-α-Glucan was found in the conidia cell wall, but was absent from the vegetative hyphae cell wall. Deletion of ags-1 affected conidial development. Δags-1 produced only 5 % as many conidia as the WT and most of the conidia produced by Δags-1 were not viable. The ags-1 upstream regulatory elements were shown to direct cell-type-specific expression of red fluorescent protein in conidia and aerial hyphae. A haemagglutinin-tagged AGS-1 was found to be expressed in aerial hyphae and conidia. The research showed that 1,3-α-glucan is an aerial hyphae and conidia cell wall component, and is required for normal conidial differentiation. PMID:24847001

  8. 9. ENGINE TEST CELL BUILDING INTERIOR. CELL ACCESS ELEVATOR, CELLS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. ENGINE TEST CELL BUILDING INTERIOR. CELL ACCESS ELEVATOR, CELLS 2 AND 4, BASEMENT LEVEL. LOOKING SOUTHEAST. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA

  9. Squamous cell skin cancer

    MedlinePlus

    ... cell; NMSC - squamous cell; Squamous cell skin cancer; Squamous cell carcinoma of the skin ... squamous cell cancer is called Bowen disease (or squamous cell carcinoma in situ). This type does not spread to ...

  10. Electrochemical cell

    DOEpatents

    Redey, L.I.; Vissers, D.R.; Prakash, J.

    1996-07-16

    An electrochemical cell is described having a bimodal positive electrode, a negative electrode of an alkali metal, and a compatible electrolyte including an alkali metal salt molten at the cell operating temperature. The positive electrode has an electrochemically active layer of at least one transition metal chloride at least partially present as a charging product, and additives of bromide and/or iodide and sulfur in the positive electrode or the electrolyte. Electrode volumetric capacity is in excess of 400 Ah/cm{sup 3}; the cell can be 90% recharged in three hours and can operate at temperatures below 160 C. There is also disclosed a method of reducing the operating temperature and improving the overall volumetric capacity of an electrochemical cell and for producing a positive electrode having a BET area greater than 6{times}10{sup 4}cm{sup 2}/g of Ni. 6 figs.

  11. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Vissers, Donald R.; Prakash, Jai

    1994-01-01

    An electrochemical cell having a bimodal positive electrode, a negative electrode of an alkali metal, and a compatible electrolyte including an alkali metal salt molten at the cell operating temperature. The positive electrode has an electrochemically active layer of at least one transition metal chloride at least partially present as a charging product, and additives of bromide and/or iodide and sulfur in the positive electrode or the electrolyte. Electrode volumetric capacity is in excess of 400 Ah/cm.sup.3 ; the cell can be 90% recharged in three hours and can operate at temperatures below 160.degree. C. There is also disclosed a method of reducing the operating temperature and improving the overall volumetric capacity of an electrochemical cell and for producing a positive electrode having a BET area greater than 6.times.10.sup.4 cm.sup.2 /g of Ni.

  12. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Vissers, Donald R.; Prakash, Jai

    1996-01-01

    An electrochemical cell having a bimodal positive electrode, a negative electrode of an alkali metal, and a compatible electrolyte including an alkali metal salt molten at the cell operating temperature. The positive electrode has an electrochemically active layer of at least one transition metal chloride at least partially present as a charging product, and additives of bromide and/or iodide and sulfur in the positive electrode or the electrolyte. Electrode volumetric capacity is in excess of 400 Ah/cm.sup.3 ; the cell can be 90% recharged in three hours and can operate at temperatures below 160.degree. C. There is also disclosed a method of reducing the operating temperature and improving the overall volumetric capacity of an electrochemical cell and for producing a positive electrode having a BET area greater than 6.times.10.sup.4 cm.sup.2 /g of Ni.

  13. Electrochemical cell

    DOEpatents

    Redey, L.I.; Vissers, D.R.; Prakash, J.

    1994-02-01

    An electrochemical cell is described having a bimodal positive electrode, a negative electrode of an alkali metal, and a compatible electrolyte including an alkali metal salt molten at the cell operating temperature. The positive electrode has an electrochemically active layer of at least one transition metal chloride at least partially present as a charging product, and additives of bromide and/or iodide and sulfur in the positive electrode or the electrolyte. Electrode volumetric capacity is in excess of 400 Ah/cm[sup 3]; the cell can be 90% recharged in three hours and can operate at temperatures below 160 C. There is also disclosed a method of reducing the operating temperature and improving the overall volumetric capacity of an electrochemical cell and for producing a positive electrode having a BET area greater than 6[times]10[sup 4] cm[sup 2]/g of Ni. 8 figures.

  14. Dry cell battery poisoning

    MedlinePlus

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  15. Load cell

    DOEpatents

    Spletzer, Barry L.

    2001-01-01

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs which can be combined to determine any one of the six general load components.

  16. Load cell

    DOEpatents

    Spletzer, B.L.

    1998-12-15

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs, each directly proportional to one of the six general load components. 16 figs.

  17. Load cell

    DOEpatents

    Spletzer, Barry L.

    1998-01-01

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs, each directly proportional to one of the six general load components.

  18. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Vissers, Donald R.; Prakash, Jai

    1994-01-01

    An electrochemical cell having an alkali metal negative electrode such as sodium and a positive electrode including Ni or transition metals, separated by a .beta." alumina electrolyte and NaAlCl.sub.4 or other compatible material. Various concentrations of a bromine, iodine and/or sulfur containing additive and pore formers are disclosed, which enhance cell capacity and power. The pore formers may be the ammonium salts of carbonic acid or a weak organic acid or oxamide or methylcellulose.

  19. Cell sealant

    SciTech Connect

    Markin, C.; Book, R.J.; James, D.A.

    1988-04-26

    An electrochemical cell is described comprising an anode, a cathode and an electrolyte disposed within an open ended cylindrical metallic cell container, with an insulative cell top member being positioned within the open end of a sealant at the interface between the cell top member and the metallic cell container. The sealant is a mixture of a Type 2 BUR asphalt and an elastomeric material selected from the group consisting of (cis-1,4-polyisoprene), styrene-butadiene copolymer (SBR), cis-1,4-polybutadiene and styrene butadiene styrene (SBS), styrene isoprene styrene (SIS), neoprene (poly-chloprene), acrylonitrile-butadiene copolymer (NBR), ethylene-propylene elastomers (EPR), butyl rubber (copolymers of isobutylene), urethane, nitrile (polymers of butadiene and acrylonitrile), polysulfide, polyacrylate, silicone, chlorosulfonated polyethylene, and EPDM (terpolymers of ethylene, propylene and diene monomers), and mixtures thereof, and wherein the elastomeric material is substantially inert to the electrolyte and is present in an amount between 0.5% to 10% by weight of the asphalt.

  20. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Myles, Kevin M.; Vissers, Donald R.; Prakash, Jai

    1996-01-01

    An electrochemical cell with a positive electrode having an electrochemically active layer of at least one transition metal chloride. A negative electrode of an alkali metal and a compatible electrolyte including an alkali metal salt molten at cell operating temperature is included in the cell. The electrolyte is present at least partially as a corrugated .beta." alumina tube surrounding the negative electrode interior to the positive electrode. The ratio of the volume of liquid electrolyte to the volume of the positive electrode is in the range of from about 0.1 to about 3. A plurality of stacked electrochemical cells is disclosed each having a positive electrode, a negative electrode of an alkali metal molten at cell operating temperature, and a compatible electrolyte. The electrolyte is at least partially present as a corrugated .beta." alumina sheet separating the negative electrode and interior to the positive electrodes. The alkali metal is retained in a porous electrically conductive ceramic, and seals for sealing the junctures of the electrolyte and the adjacent electrodes at the peripheries thereof.

  1. Electrochemical cell

    DOEpatents

    Redey, L.I.; Myles, K.M.; Vissers, D.R.; Prakash, J.

    1996-07-02

    An electrochemical cell is described with a positive electrode having an electrochemically active layer of at least one transition metal chloride. A negative electrode of an alkali metal and a compatible electrolyte including an alkali metal salt molten at cell operating temperature is included in the cell. The electrolyte is present at least partially as a corrugated {beta}{double_prime} alumina tube surrounding the negative electrode interior to the positive electrode. The ratio of the volume of liquid electrolyte to the volume of the positive electrode is in the range of from about 0.1 to about 3. A plurality of stacked electrochemical cells is disclosed each having a positive electrode, a negative electrode of an alkali metal molten at cell operating temperature, and a compatible electrolyte. The electrolyte is at least partially present as a corrugated {beta}{double_prime} alumina sheet separating the negative electrode and interior to the positive electrodes. The alkali metal is retained in a porous electrically conductive ceramic, and seals for sealing the junctures of the electrolyte and the adjacent electrodes at the peripheries thereof. 8 figs.

  2. Electrochemical cell

    DOEpatents

    Nagy, Zoltan; Yonco, Robert M.; You, Hoydoo; Melendres, Carlos A.

    1992-01-01

    An electrochemical cell has a layer-type or sandwich configuration with a Teflon center section that houses working, reference and counter electrodes and defines a relatively narrow electrolyte cavity. The center section is surrounded on both sides with thin Teflon membranes. The membranes are pressed in place by a pair of Teflon inner frames which are in turn supported by a pair of outer metal frames. The pair of inner and outer frames are provided with corresponding, appropriately shaped slits that are in plane generally transverse to the plane of the working electrode and permit X-ray beams to enter and exit the cell through the Teflon membranes that cover the slits so that the interface between the working electrode and the electrolyte within the cell may be analyzed by transmission geometry. In one embodiment, the center section consists of two parts, one on top of the other. Alternatively, the center section of the electrochemical cell may consist of two intersliding pieces or may be made of a single piece of Teflon sheet material. The electrolyte cavity is shaped so that the electrochemical cell can be rotated 90.degree. in either direction while maintaining the working and counter electrodes submerged in the electrolyte.

  3. Electrochemical cell

    DOEpatents

    Nagy, Z.; Yonco, R.M.; You, H.; Melendres, C.A.

    1992-08-25

    An electrochemical cell has a layer-type or sandwich configuration with a Teflon center section that houses working, reference and counter electrodes and defines a relatively narrow electrolyte cavity. The center section is surrounded on both sides with thin Teflon membranes. The membranes are pressed in place by a pair of Teflon inner frames which are in turn supported by a pair of outer metal frames. The pair of inner and outer frames are provided with corresponding, appropriately shaped slits that are in plane generally transverse to the plane of the working electrode and permit X-ray beams to enter and exit the cell through the Teflon membranes that cover the slits so that the interface between the working electrode and the electrolyte within the cell may be analyzed by transmission geometry. In one embodiment, the center section consists of two parts, one on top of the other. Alternatively, the center section of the electrochemical cell may consist of two intersliding pieces or may be made of a single piece of Teflon sheet material. The electrolyte cavity is shaped so that the electrochemical cell can be rotated 90[degree] in either direction while maintaining the working and counter electrodes submerged in the electrolyte. 5 figs.

  4. Cell Phones

    PubMed Central

    Sansone, Lori A.

    2013-01-01

    Cell phones are a relatively novel and evolving technology. While the potential benefits of this technology continue to emerge, so do the potential psychosocial risks. For example, one psychosocial risk is user stress, which appears to be related to feeling compelled to promptly respond to cell-phone activity in order to maintain spontaneity and access with others. Other potential psychosocial risks include disruptions in sleep; the user’s risk of exposure to cyberbullying, particularly the unwanted exposure of photographs and/or videos of the victim; and overuse, particularly among adolescents. With regard to the latter phenomenon, the boundaries among overuse, misuse, dependence, and addiction are not scientifically clear. Therefore, while cell phones are a convenient and expedient technology, they are not without their potential psychosocial hazards. PMID:23439568

  5. Solar cells

    NASA Astrophysics Data System (ADS)

    Treble, F. C.

    1980-11-01

    The history, state of the art, and future prospects of solar cells are reviewed. Solar cells are already competitive in a wide range of low-power applications, and during the 1980's they are expected to become cheaper to run than diesel or gasoline generators, the present mainstay of isolated communities. At this stage they will become attractive for water pumping, irrigation, and rural electrification, particularly in developing countries. With further cost reduction, they may be used to augment grid supplies in domestic, commercial, institutional, and industrial premises. Cost reduction to the stage where photovoltaics becomes economic for large-scale power generation in central stations depends on a technological breakthrough in the development of thin-film cells. DOE aims to reach this goal by 1990, so that by the end of the century about 20% of the estimated annual additions to their electrical generating capacity will be photovoltaic.

  6. Electrochemical cell

    DOEpatents

    Kaun, T.D.

    An improved secondary electrochemical cell is disclosed having a negative electrode of lithium aluminum, a positive electrode of iron sulfide, a molten electrolyte of lithium chloride and potassium chloride, and the combination that the fully charged theoretical capacity of the negative electrode is in the range of 0.5 to 1.0 that of the positive electrode. The cell thus is negative electrode limiting during discharge cycling. Preferably, the negative electrode contains therein, in the approximate range of 1 to 10 volume % of the electrode, an additive from the materials of graphitized carbon, aluminum-iron alloy, and/or magnesium oxide.

  7. Electrochemical cell

    DOEpatents

    Redey, L.I.; Vissers, D.R.; Prakash, J.

    1994-08-23

    An electrochemical cell is described having an alkali metal negative electrode such as sodium and a positive electrode including Ni or transition metals, separated by a [beta] alumina electrolyte and NaAlCl[sub 4] or other compatible material. Various concentrations of a bromine, iodine and/or sulfur containing additive and pore formers are disclosed, which enhance cell capacity and power. The pore formers may be the ammonium salts of carbonic acid or a weak organic acid or oxamide or methylcellulose. 6 figs.

  8. Cell Libraries

    NASA Technical Reports Server (NTRS)

    1994-01-01

    A NASA contract led to the development of faster and more energy efficient semiconductor materials for digital integrated circuits. Gallium arsenide (GaAs) conducts electrons 4-6 times faster than silicon and uses less power at frequencies above 100-150 megahertz. However, the material is expensive, brittle, fragile and has lacked computer automated engineering tools to solve this problem. Systems & Processes Engineering Corporation (SPEC) developed a series of GaAs cell libraries for cell layout, design rule checking, logic synthesis, placement and routing, simulation and chip assembly. The system is marketed by Compare Design Automation.

  9. Electrochemical cell

    DOEpatents

    Kaun, Thomas D.

    1984-01-01

    An improved secondary electrochemical cell is disclosed having a negative electrode of lithium aluminum, a positive electrode of iron sulfide, a molten electrolyte of lithium chloride and potassium chloride, and the combination that the fully charged theoretical capacity of the negative electrode is in the range of 0.5-1.0 that of the positive electrode. The cell thus is negative electrode limiting during discharge cycling. Preferably, the negative electrode contains therein, in the approximate range of 1-10 volume % of the electrode, an additive from the materials of graphitized carbon, aluminum-iron alloy, and/or magnesium oxide.

  10. Stem Cell Basics

    MedlinePlus

    ... stem cells? What are the potential uses of human stem cells and the obstacles that must be overcome before ... two kinds of stem cells from animals and humans: embryonic stem cells and non-embryonic "somatic" or "adult" stem cells . ...

  11. Stem Cell Information: Glossary

    MedlinePlus

    ... based therapies Cell culture Cell division Chromosome Clone Cloning Cord blood stem cells Culture medium Differentiation Directed ... Pluripotent Polar body Preimplantation Proliferation Regenerative medicine Reproductive cloning Signals Somatic cell Somatic cell nuclear transfer (SCNT) ...

  12. Learn About Stem Cells

    MedlinePlus

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... ISSCR Get Involved Media © 2015 International Society for Stem Cell Research Terms of Use Disclaimer Privacy Policy

  13. Photoelectrodialytic cell

    DOEpatents

    Murphy, G.W.

    1983-09-13

    A multicompartment photoelectrodialytic demineralization cell is provided with a buffer compartment interposed between the product compartment and a compartment containing an electrolyte solution. Semipermeable membranes separate the buffer compartment from the product and electrolyte compartments. The buffer compartment is flushed to prevent leakage of the electrolyte compartment from entering the product compartment. 3 figs.

  14. Photovoltaic cell

    DOEpatents

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  15. Nonaqueous cell

    SciTech Connect

    Kalnoki-kis, T.

    1981-07-07

    A nonaqueous cell is disclosed that utlizes an active metal anode, such as lithium, a cathode collector and an ionically conductive cathode electrolyte comprising a solute dissolved in a liquid cathode, such as an oxyhalide, and wherein a vinyl polymer is dissolved in the cathode-electrolyte.

  16. Potent Cells

    ERIC Educational Resources Information Center

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  17. 19. Oblique, typical cell (south cells) from rear of cell; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Oblique, typical cell (south cells) from rear of cell; view to north, 65mm lens with electronic flash illumination. - Tule Lake Project Jail, Post Mile 44.85, State Route 139, Newell, Modoc County, CA

  18. Reprogrammed pluripotent stem cells from somatic cells.

    PubMed

    Kim, Jong Soo; Choi, Hyun Woo; Choi, Sol; Do, Jeong Tae

    2011-06-01

    Pluripotent stem cells, such as embryonic stem (ES) cells, can differentiate into all cell types. So, these cells can be a biological resource for regenerative medicine. However, ES cells known as standard pluripotent cells have problem to be used for cell therapy because of ethical issue of the origin and immune response on the graft. Hence, recently reprogrammed pluripotent cells have been suggested as an alternative source for regenerative medicine. Somatic cells can acquire the ES cell-like pluripotency by transferring somatic cell nuclei into oocytes, by cell fusion with pluripotent cells. Retroviral-mediated introduction of four factors, Oct4, Sox2, Klf4 and c-Myc can successfully reprogram somatic cells into ES cell-like pluripotent stem cells, known as induced pluripotent stem (iPS) cells. These cells closely resemble ES cells in gene expression pattern, cell biologic and phenotypic characteristics. However, to reach the eventual goal of clinical application, it is necessary to overcome the major drawbacks such as low reprogramming efficiency and genomic alterations due to viral integration. In this review, we discuss the current reprogramming techniques and mechanisms of nuclear reprogramming induced by transcription factor transduction. PMID:24298328

  19. Ghost cell lesions

    PubMed Central

    Rajesh, E.; Jimson, Sudha; Masthan, K. M. K.; Balachander, N.

    2015-01-01

    Ghost cells have been a controversy for a long time. Ghost cell is a swollen/enlarged epithelial cell with eosnophilic cytoplasm, but without a nucleus. In routine H and E staining these cells give a shadowy appearance. Hence these cells are also called as shadow cells or translucent cells. The appearance of these cells varies from lesion to lesion involving odontogenic and nonodontogenic lesions. This article review about the origin, nature and significance of ghost cells in different neoplasms. PMID:26015694

  20. Crystalline Silicon Solar Cells

    NASA Astrophysics Data System (ADS)

    Green, Martin A.

    2015-10-01

    The following sections are included: * Overview * Silicon cell development * Substrate production * Cell processing * Cell costs * Opportunities for improvement * Silicon-supported thin films * Summary * Acknowledgement * References

  1. Red blood cells, sickle cell (image)

    MedlinePlus

    Sickle cell anemia is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). ... abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in this photomicrograph.

  2. Red blood cells, sickle cells (image)

    MedlinePlus

    These crescent or sickle-shaped red blood cells (RBCs) are present with Sickle cell anemia, and stand out clearly against the normal round RBCs. These abnormally shaped cells may become entangled and ...

  3. Red blood cells, sickle cell (image)

    MedlinePlus

    Sickle cell anemia is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). The abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in this photomicrograph.

  4. Red blood cells, multiple sickle cells (image)

    MedlinePlus

    Sickle cell anemia is an inherited disorder in which abnormal hemoglobin (the red pigment inside red blood cells) is produced. The abnormal hemoglobin causes red blood cells to assume a sickle shape, like the ones seen in this photomicrograph.

  5. Robotic adherent cell injection for characterizing cell-cell communication.

    PubMed

    Liu, Jun; Siragam, Vinayakumar; Gong, Zheng; Chen, Jun; Fridman, Michael D; Leung, Clement; Lu, Zhe; Ru, Changhai; Xie, Shaorong; Luo, Jun; Hamilton, Robert M; Sun, Yu

    2015-01-01

    Compared to robotic injection of suspended cells (e.g., embryos and oocytes), fewer attempts were made to automate the injection of adherent cells (e.g., cancer cells and cardiomyocytes) due to their smaller size, highly irregular morphology, small thickness (a few micrometers thick), and large variations in thickness across cells. This paper presents a robotic system for automated microinjection of adherent cells. The system is embedded with several new capabilities: automatically locating micropipette tips; robustly detecting the contact of micropipette tip with cell culturing surface and directly with cell membrane; and precisely compensating for accumulative positioning errors. These new capabilities make it practical to perform adherent cell microinjection truly via computer mouse clicking in front of a computer monitor, on hundreds and thousands of cells per experiment (versus a few to tens of cells as state of the art). System operation speed, success rate, and cell viability rate were quantitatively evaluated based on robotic microinjection of over 4000 cells. This paper also reports the use of the new robotic system to perform cell-cell communication studies using large sample sizes. The gap junction function in a cardiac muscle cell line (HL-1 cells), for the first time, was quantified with the system. PMID:25073160

  6. Sickle cell test

    MedlinePlus

    The sickle cell test looks for the abnormal hemoglobin in the blood that causes the disease sickle cell anemia . ... if a person has abnormal hemoglobin that causes sickle cell disease and sickle cell trait. Hemoglobin is a ...

  7. Sickle cell anemia

    MedlinePlus

    Anemia - sickle cell; Hemoglobin SS disease (Hb SS); Sickle cell disease ... Sickle cell anemia is caused by an abnormal type of hemoglobin called hemoglobin S. Hemoglobin is a protein inside red blood cells ...

  8. Stem cell glycolipids.

    PubMed

    Yanagisawa, Makoto

    2011-09-01

    Glycolipids are compounds containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety. Because of their expression patterns and the intracellular localization patterns, glycolipids, including stage-specific embryonic antigens (SSEA-3, SSEA-4, and possibly SSEA-1) and gangliosides (e.g., GD3, GD2, and A2B5 antigens), have been used as marker molecules of stem cells. In this review, I will introduce glycolipids expressed in pluripotent stem cells (embryonic stem cells, induced pluripotent stem cells, very small embryonic-like stem cells, amniotic stem cells, and multilineage-differentiating stress enduring cells), multipotent stem cells (neural stem cells, mesenchymal stem cells, fetal liver multipotent progenitor cells, and hematopoietic stem cells), and cancer stem cells (brain cancer stem cells and breast cancer stem cells), and discuss their availability as biomarkers for identifying and isolating stem cells. PMID:21161592

  9. Murine Mueller cells are progenitor cells for neuronal cells and fibrous tissue cells

    SciTech Connect

    Florian, Christian; Langmann, Thomas; Weber, Bernhard H.F.; Morsczeck, Christian

    2008-09-19

    Mammalian Mueller cells have been reported to possess retinal progenitor cell properties and generate new neurons after injury. This study investigates murine Mueller cells under in vitro conditions for their capability of dedifferentiation into retinal progenitor cells. Mueller cells were isolated from mouse retina, and proliferating cells were expanded in serum-containing medium. For dedifferentiation, the cultured cells were transferred to serum-replacement medium (SRM) at different points in time after their isolation. Interestingly, early cell passages produced fibrous tissue in which extracellular matrix proteins and connective tissue markers were differentially expressed. In contrast, aged Mueller cell cultures formed neurospheres in SRM that are characteristic for neuronal progenitor cells. These neurospheres differentiated into neuron-like cells after cultivation on laminin/ornithine cell culture substrate. Here, we report for the first time that murine Mueller cells can be progenitors for both, fibrous tissue cells and neuronal cells, depending on the age of the cell culture.

  10. Electrorefining cell evaluation

    SciTech Connect

    Bronson, M.C.; Thomas, R.L.

    1989-04-14

    Operational characteristics of the LANL electrorefining cell, a modified LANL electrorefining cell, and an advanced electrorefining cell (known as the CRAC cell) were determined. Average process yields achieved were: 75% for the LANL cell, 82% for the modified LANL cell, and 86% for the CRAC cell. All product metal from the LANL and modified LANL cells was within foundry specifications. Metal from one run in the CRAC cell exceeded foundry specifications for tantalum. The LANL and modified LANL cells were simple in design and operation, but product separation was more labor intensive than with the CRAC cell. The CRAC cell was more complicated in design but remained relatively simple in operation. A decision analysis concluded that the modified LANL cell was the preferred cell. It was recommended that the modified LANL cell be implemented by the Plutonium Recovery Project at Rocky Flats and that development of the CRAC cell continue. 8 refs., 22 figs., 12 tabs.

  11. Leydig cells: From stem cells to aging.

    PubMed

    Chen, Haolin; Ge, Ren-Shan; Zirkin, Barry R

    2009-07-10

    Leydig cells are the testosterone-producing cells of the testis. The adult Leydig cell population ultimately develops from undifferentiated mesenchymal-like stem cells present in the interstitial compartment of the neonatal testis. Four distinct stages of adult Leydig cell development have been identified and characterized: stem Leydig cells, progenitor Leydig cells, immature Leydig cells and adult Leydig cells. The stem Leydig cells are undifferentiated cells that are capable of indefinite self-renewal, differentiation, and replenishment of the Leydig cell niche. Progenitor Leydig cells are derived from the stem Leydig cells. These spindle-shaped cells are luteinizing hormone (LH) receptor positive, have high mitotic activity, and produce little testosterone but rather testosterone metabolites. The progenitor Leydig cells give rise to immature Leydig cells which are round, contain large amounts of smooth endoplasmic reticulum, and produce some testosterone but also very high levels of testosterone metabolites. A single division of these cells produces adult Leydig cells, which are terminally differentiated cells that produce high levels of testosterone. As men age, serum testosterone levels decline, and this is associated with alterations in body composition, energy level, muscle strength, physical, sexual and cognitive functions, and mood. In the Brown Norway rat, used extensively as a model for male reproductive aging, age-related reductions in serum testosterone result from significant decline in the ability of aged Leydig cells to produce testosterone in response to LH stimulation. This review describes Leydig cell development and aging. Additionally, the molecular mechanisms by which testosterone synthesis declines with aging are discussed. PMID:19481681

  12. Fuel cells: A handbook

    NASA Astrophysics Data System (ADS)

    Kinoshita, K.; McLarnon, F. R.; Cairns, E. J.

    1988-05-01

    The purpose of this handbook is to present information describing fuel cells that is helpful to scientists, engineers, and technical managers who are not experienced in this technology, as well as to provide an update on the current technical status of the various types of fuel cells. Following the introduction, contents of this handbook are: fuel cell performance variables; phosphoric acid fuel cell; molten carbonate fuel cell; solid oxide fuel cell; alternative fuel cell technologies; fuel cell systems; and concluding remarks.

  13. CORONAL CELLS

    SciTech Connect

    Sheeley, N. R. Jr.; Warren, H. P. E-mail: harry.warren@nrl.navy.mil

    2012-04-10

    We have recently noticed cellular features in Fe XII 193 A images of the 1.2 MK corona. They occur in regions bounded by a coronal hole and a filament channel, and are centered on flux elements of the photospheric magnetic network. Like their neighboring coronal holes, these regions have minority-polarity flux that is {approx}0.1-0.3 times their flux of majority polarity. Consequently, the minority-polarity flux is 'grabbed' by the majority-polarity flux to form low-lying loops, and the remainder of the network flux escapes to connect with its opposite-polarity counterpart in distant active regions of the Sun. As these regions are carried toward the limb by solar rotation, the cells disappear and are replaced by linear plumes projecting toward the limb. In simultaneous views from the Solar Terrestrial Relations Observatory and Solar Dynamics Observatory spacecraft, these plumes project in opposite directions, extending away from the coronal hole in one view and toward the hole in the other view, suggesting that they are sky-plane projections of the same radial structures. We conclude that these regions are composed of closely spaced radial plumes, extending upward like candles on a birthday cake and visible as cells when seen from above. We suppose that a coronal hole has this same discrete, cellular magnetic structure, but that it is not seen until the encroachment of opposite-polarity flux closes part or all of the hole.

  14. Molluscan cells in culture: primary cell cultures and cell lines

    PubMed Central

    Yoshino, T. P.; Bickham, U.; Bayne, C. J.

    2013-01-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as biomonitors for environmental contaminants, as models for gene transfer technologies, and for studies of innate immunity and neoplastic disease. Despite efforts to isolate proliferative cell lines from molluscs, the snail Biomphalaria glabrata Say, 1818 embryonic (Bge) cell line is the only existing cell line originating from any molluscan species. Taking an organ systems approach, this review summarizes efforts to establish molluscan cell cultures and describes the varied applications of primary cell cultures in research. Because of the unique status of the Bge cell line, an account is presented of the establishment of this cell line, and of how these cells have contributed to our understanding of snail host-parasite interactions. Finally, we detail the difficulties commonly encountered in efforts to establish cell lines from molluscs and discuss how these difficulties might be overcome. PMID:24198436

  15. Indium phosphide solar cells

    NASA Technical Reports Server (NTRS)

    Weinberg, Irving

    1991-01-01

    The direction for InP solar cell research; reduction of cell cost; increase of cell efficiency; measurements needed to better understand cell performance; n/p versus p/n; radiation effects; major problems in cell contacting; and whether the present level of InP solar cell research in the USA should be maintained, decreased, or increased were considered.

  16. Endothelial cell Ca2+ increases upon tumor cell contact and modulates cell-cell adhesion.

    PubMed Central

    Pili, R; Corda, S; Passaniti, A; Ziegelstein, R C; Heldman, A W; Capogrossi, M C

    1993-01-01

    The signal transduction mechanisms involved in tumor cell adhesion to endothelial cells are still largely undefined. The effect of metastatic murine melanoma cell and human prostate carcinoma cell contact on cytosolic [Ca2+] of bovine artery endothelial cells was examined in indo-1-loaded endothelial cell monolayers. A rapid increase in endothelial cell [Ca2+] occurred on contact with tumor cells, but not on contact with 8-microns inert beads. A similar increase in endothelial cell [Ca2+] was observed with human neutrophils or monocyte-like lymphoma cells, but not with endothelial cells, red blood cells, and melanoma cell-conditioned medium. The increase in endothelial cell [Ca2+] was not inhibited by extracellular Ca2+ removal. In contrast, endothelial cell pretreatment with thapsigargin, which releases endoplasmic reticulum Ca2+ into the cytosol and depletes this Ca2+ store site, abolished the cytosolic [Ca2+] rise upon melanoma cell contact. Endothelial cell pretreatment with the membrane-permeant form of the Ca2+ chelator bis-(O-aminophenoxyl)ethane-N,N,N',N'-tetraacetic acid blocked the increase in cytosolic [Ca2+]. Under static and dynamic flow conditions (0.46 dyn/cm2) bis-(O-aminophenoxyl)ethane-N,N,N',N'-tetraacetic acid pretreatment of bovine pulmonary artery endothelial cell monolayers inhibited melanoma cell adhesion to the endothelial cells. Thus, tumor cell contact with endothelial cells induces a rapid Ca2+ release from endothelial intracellular stores, which has a functional role in enhancing cell-cell adhesion. Images PMID:8254056

  17. DNA-cell conjugates

    DOEpatents

    Hsiao, Shih-Chia; Francis, Matthew B.; Bertozzi, Carolyn; Mathies, Richard; Chandra, Ravi; Douglas, Erik; Twite, Amy; Toriello, Nicholas; Onoe, Hiroaki

    2016-05-03

    The present invention provides conjugates of DNA and cells by linking the DNA to a native functional group on the cell surface. The cells can be without cell walls or can have cell walls. The modified cells can be linked to a substrate surface and used in assay or bioreactors.

  18. Cell-cell interactions on solid matrices.

    PubMed

    Louis, Nancy A; Daniels, Dionne; Colgan, Sean P

    2006-01-01

    Models to study molecular, biochemical, and functional responses in vitro generally incorporate an individual cell type or group of cells organized in a random fashion. Normal physiological responses in vivo require that individual cell types be oriented in an organized fashion with three-dimensional architecture and appropriately positioned cellular interfaces. Much recent progress has been made in the development and implementation of models to study cell-cell contact using substrate grown cells. Here, we summarize the use of membrane permeable supports to study functional responses in appropriately positioned cell types. These models incorporate two or more different cells cultured in physiologically positioned locales on solid substrates. Models incorporating nonadherent cells (e.g., leukocytes) in co-culture with such models also are discussed. Such models have been used extensively to discovery both cell-bound as well as soluble mediators of physiological and pathophysiological processes. PMID:16799188

  19. Photovoltaic cell

    SciTech Connect

    Jordan, J.F.; Lampkin, C.M.

    1981-12-08

    A photovoltaic cell has: an electrically conductive substrate, which may be glass having a film of conductive tin oxide; a first layer containing a suitable semiconductor, which layer has a first component film with an amorphous structure and a second component film with a polycrystalline structure; a second layer forming a heterojunction with the first layer; and suitable electrodes where the heterojunction is formed from a solution containing copper, the amorphous film component is superposed above an electrically conductive substrate to resist permeation of the copper-containing material to shorting electrical contact with the substrate. The penetration resistant amporphous layer permits a variety of processes to be used in forming the heterojunction with even very thin layers (1-6 mu thick) of underlying polycrystalline semi-conductor materials. In some embodiments, the amorphous-like structure may be formed by the addition of aluminum or zirconium compounds to a solution of cadmium salts sprayed over a heated substrate.

  20. Photoelectrochemical cell

    DOEpatents

    Rauh, R. David; Boudreau, Robert A.

    1983-06-14

    A photoelectrochemical cell comprising a sealed container having a light-transmitting window for admitting light into the container across a light-admitting plane, an electrolyte in the container, a photoelectrode in the container having a light-absorbing surface arranged to receive light from the window and in contact with the electrolyte, the surface having a plurality of spaced portions oblique to the plane, each portion having dimensions at least an order of magnitude larger than the maximum wavelength of incident sunlight, the total surface area of the surface being larger than the area of the plane bounded by the container, and a counter electrode in the container in contact with the electrolyte.

  1. Effect of Vaginal or Systemic Estrogen on Dynamics of Collagen Assembly in the Rat Vaginal Wall1

    PubMed Central

    Montoya, T. Ignacio; Maldonado, P. Antonio; Acevedo, Jesus F.; Word, R. Ann

    2014-01-01

    ABSTRACT The objective of this study was to compare the effects of systemic and local estrogen treatment on collagen assembly and biomechanical properties of the vaginal wall. Ovariectomized nulliparous rats were treated with estradiol or conjugated equine estrogens (CEEs) either systemically, vaginal CEE, or vaginal placebo cream for 4 wk. Low-dose local CEE treatment resulted in increased vaginal epithelial thickness and significant vaginal growth without uterine hyperplasia. Furthermore, vaginal wall distensibility increased without compromise of maximal force at failure. Systemic estradiol resulted in modest increases in collagen type I with no change in collagen type III mRNA. Low-dose vaginal treatment, however, resulted in dramatic increases in both collagen subtypes whereas moderate and high dose local therapies were less effective. Consistent with the mRNA results, low-dose vaginal estrogen resulted in increased total and cross-linked collagen content. The inverse relationship between vaginal dose and collagen expression may be explained in part by progressive downregulation of estrogen receptor-alpha mRNA with increasing estrogen dose. We conclude that, in this menopausal rat model, local estrogen treatment increased total and cross-linked collagen content and markedly stimulated collagen mRNA expression in an inverse dose-effect relationship. High-dose vaginal estrogen resulted in downregulation of estrogen receptor-alpha and loss of estrogen-induced increases in vaginal collagen. These results may have important clinical implications regarding the use of local vaginal estrogen therapy and its role as an adjunctive treatment in women with loss of vaginal support. PMID:25537371

  2. Integrated circuit cell library

    NASA Technical Reports Server (NTRS)

    Whitaker, Sterling R. (Inventor); Miles, Lowell H. (Inventor)

    2005-01-01

    According to the invention, an ASIC cell library for use in creation of custom integrated circuits is disclosed. The ASIC cell library includes some first cells and some second cells. Each of the second cells includes two or more kernel cells. The ASIC cell library is at least 5% comprised of second cells. In various embodiments, the ASIC cell library could be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more comprised of second cells.

  3. Waiting for the Great Pumpkin? On the Whereabouts of Justification in Library Research: A Symposium.

    ERIC Educational Resources Information Center

    Henige, David; And Others

    1992-01-01

    This symposium report includes seven papers that address issues concerning the North American Collections Inventory Project (NCIP) Conspectus sponsored by the Research Libraries Group (RLG). Topics discussed include cooperative collection development; rigor and research in library and information science; decision making and uncertainty; and data…

  4. In or Out of the Pumpkin Shell? Sex Role Differentiation in Classroom Interaction.

    ERIC Educational Resources Information Center

    Cooper, Pamela J.

    A review of research on sex role differentiation in classroom interaction reveals that women are marginalized from education by its content and by the classroom interactional processes. Sex-role stereotyping exists in curriculum materials at all educational levels, with textbooks more likely to portray boys in active roles and girls in passive…

  5. DOE ZERH Case Study: Hammer and Hand, Pumpkin Ridge Passive House, North Plains, OR

    SciTech Connect

    none,

    2015-09-01

    Case study of a DOE 2015 Housing Innovation Award winning custom home in the marine climate that got a HERS 49 without PV, or HERS 5 with PV, with 2x4 24” on center walls plus 8” exterior cavity together dense-packed with R-60 cellulose; daylight basement with R-29 rigid EPS foam under slab; vented attic with R-86 blown cellulose; minisplit heat pump; ducted with HRV; 15.5 SEER; 10 HSPF.

  6. When pumpkin is closer to onion than to squash: The structure of the second language lexicon.

    PubMed

    Borodkin, Katy; Kenett, Yoed N; Faust, Miriam; Mashal, Nira

    2016-11-01

    The current research investigated the organization of the second language mental lexicon. Twenty-seven English-Hebrew bilingual speakers (who spoke Hebrew as their second language) completed a semantic fluency task in each of their languages, and 24 native Hebrew speakers completed the task in Hebrew. Responses were compared within and across groups, using computational tools. The analyses indicated that the lexical network of the second language displayed greater local connectivity and less modular community structure than the network in the native language, both in the entire sample and in a sub-sample of bilinguals whose Hebrew vocabulary was matched to that of the native Hebrew speakers. These findings suggest that the lexical network of the second language is not as well-organized as is the network of the first language, even in highly proficient bilinguals. The structural characteristics of the second language lexicon might be affected by factors related to language learning history, including age of acquisition and language use. PMID:27513870

  7. Special considerations for qualifying thin films for super pressure pumpkin ultra long duration balloon missions

    NASA Astrophysics Data System (ADS)

    Said, Magdi A.

    2004-01-01

    The assessment of creep and dynamic response behaviors on materials intended for ultra long duration balloon (ULDB) applications is essential. The first provides needed information for design and fabrication. The second ensures that the film is sufficiently tough to survive the dynamic events during launch and ascent. Characterization and assessment of these two important parameters are discussed in this paper. Visco-elastic behavior of materials in a loaded structure, such as the ULDB film change their geometry significantly over time under load causing possible changes in the load path and the stress distribution. These changes must be held in check to satisfy the functional requirements of the structure over its service life. Typically, the balloon experiences during its service life various environmental conditions each with a different creep response. These are characterized by a simplified load temperature history for the purpose of lifetime response assessment. At mid-latitudes a significant portion of the service life is spent at night, i.e., at low temperature and low load; for the ULDB film this night-time contribution to creep is negligible. By contrast, flight exposure in an Antarctic summer is at an almost constant high temperature and corresponding high pressure. This paper presents the creep behavior of the ULDB film as a function of load, temperature, and time along with an overview of its implementation in the design. In addition, it presents a quantitative assessment on the toughness of the material under dynamic "Snatch" loading.

  8. Pizzas, Pennies and Pumpkin Seeds: Mathematical Activities for Parents and Children.

    ERIC Educational Resources Information Center

    Apelman, Maja; King, Julie

    Children have many natural opportunities to learn about the basic aspects of quantity. This booklet is addressed to parents who want to support their children's mathematical growth. The activities presented suggest many ways in which parents and children can use mathematics in their environment. The activities are organized around common…

  9. Investigation of an outbreak of Fusarium foot and fruit rot of pumpkins within the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Isolates of two biologically and phylogenetically distinct species, referred to as Fusarium solani f. sp. cucurbitae race 1 (Fsc-1 = Nectria haematococca mating population I [MPI]) and F. solani f. sp. cucurbitae race 2 (Fsc-2 = N. haematococca mating population V [MPV]), were suspected of causing a...

  10. Detection of yellow vine disease in squash and pumpkin in Massachusetts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two commercial plots of summer squash in Charlemont, Franklin County, MA were devastated in 1999 by 100% incidence of a yellowing disease resembling cucurbit yellow vine. Both plots were established during the third week of May, one with transplants and the second by direct-seeding. The plots consis...

  11. The Pumpkin or the Tiger? Michael Polanyi, Frederick Soddy, and Anticipating Emerging Technologies.

    PubMed

    Guston, David H

    2012-09-01

    Imagine putting together a jigsaw puzzle that works like the board game in the movie "Jumanji": When you finish, whatever the puzzle portrays becomes real. The children playing "Jumanji" learn to prepare for the reality that emerges from the next throw of the dice. But how would this work for the puzzle of scientific research? How do you prepare for unlocking the secrets of the atom, or assembling from the bottom-up nanotechnologies with unforeseen properties - especially when completion of such puzzles lies decades after the first scattered pieces are tentatively assembled? In the inaugural issue of this journal, Michael Polanyi argued that because the progress of science is unpredictable, society must only move forward with solving the puzzle until the picture completes itself. Decades earlier, Frederick Soddy argued that once the potential for danger reveals itself, one must reorient the whole of one's work to avoid it. While both scientists stake out extreme positions, Soddy's approach - together with the action taken by the like-minded Leo Szilard - provides a foundation for the anticipatory governance of emerging technologies. This paper narrates the intertwining stories of Polanyi, Soddy and Szilard, revealing how anticipation influenced governance in the case of atomic weapons and how Polanyi's claim in "The Republic of Science" of an unpredictable and hence ungovernable science is faulty on multiple levels. PMID:23024398

  12. Monitoring cell growth.

    PubMed

    Strober, W

    2001-05-01

    This appendix provides two protocols for monitoring cell growth. Counting cells using a hemacytometer is tedious but it allows one to effectively distinguish live cells from dead cells (using Trypan Blue exclusion). In addition, this procedure is less subject to errors due to cell clumping or heterogeneity of cell size. The use of an electronic cell counter is quicker and easier than counting cells using a hemacytometer. However, an electronic cell counter as currently constructed does not distinguish live from dead cells in a reliable fashion and is subject to error due to the presence of cell clumps. Overall, the electronic cell counter is best reserved for repetitive and rapid counting of fresh peripheral blood cells and should be used with caution when counting cell populations derived from tissues. PMID:18432653

  13. Automated Cell-Cutting for Cell Cloning

    NASA Astrophysics Data System (ADS)

    Ichikawa, Akihiko; Tanikawa, Tamio; Matsukawa, Kazutsugu; Takahashi, Seiya; Ohba, Kohtaro

    We develop an automated cell-cutting technique for cell cloning. Animal cells softened by the cytochalasin treatment are injected into a microfluidic chip. The microfluidic chip contains two orthogonal channels: one microchannel is wide, used to transport cells, and generates the cutting flow; the other is thin and used for aspiration, fixing, and stretching of the cell. The injected cell is aspirated and stretched in the thin microchannel. Simultaneously, the volumes of the cell before and after aspiration are calculated; the volumes are used to calculate the fluid flow required to aspirate half the volume of the cell into the thin microchannel. Finally, we apply a high-speed flow in the orthogonal microchannel to bisect the cell. This paper reports the cutting process, the cutting system, and the results of the experiment.

  14. Eukaryotic Cells and their Cell Bodies: Cell Theory Revised

    PubMed Central

    BALUŠKA, FRANTIŠEK; VOLKMANN, DIETER; BARLOW, PETER W.

    2004-01-01

    • Background Cell Theory, also known as cell doctrine, states that all eukaryotic organisms are composed of cells, and that cells are the smallest independent units of life. This Cell Theory has been influential in shaping the biological sciences ever since, in 1838/1839, the botanist Matthias Schleiden and the zoologist Theodore Schwann stated the principle that cells represent the elements from which all plant and animal tissues are constructed. Some 20 years later, in a famous aphorism Omnis cellula e cellula, Rudolf Virchow annunciated that all cells arise only from pre‐existing cells. General acceptance of Cell Theory was finally possible only when the cellular nature of brain tissues was confirmed at the end of the 20th century. Cell Theory then rapidly turned into a more dogmatic cell doctrine, and in this form survives up to the present day. In its current version, however, the generalized Cell Theory developed for both animals and plants is unable to accommodate the supracellular nature of higher plants, which is founded upon a super‐symplasm of interconnected cells into which is woven apoplasm, symplasm and super‐apoplasm. Furthermore, there are numerous examples of multinucleate coenocytes and syncytia found throughout the eukaryote superkingdom posing serious problems for the current version of Cell Theory. • Scope To cope with these problems, we here review data which conform to the original proposal of Daniel Mazia that the eukaryotic cell is composed of an elemental Cell Body whose structure is smaller than the cell and which is endowed with all the basic attributes of a living entity. A complement to the Cell Body is the Cell Periphery Apparatus, which consists of the plasma membrane associated with other periphery structures. Importantly, boundary stuctures of the Cell Periphery Apparatus, although capable of some self‐assembly, are largely produced and maintained by Cell Body activities and can be produced from it de novo. These

  15. Photovoltaic cell

    SciTech Connect

    Jordan, J. F.; Lampkin, C. M.

    1981-02-03

    A photovoltaic cell is disclosed having an electrically conductive substrate, which may be glass having a film of conductive tin oxide. A first layer contains a suitable semiconductor, which layer has a first component film with an amorphous structure and a second component film with a polycrystalline structure a second layer forms a heterojunction with the first layer suitable electrodes are provided where the heterojunction is formed from a solution containing copper, and the amorphous film component is superposed above an electrically conductive substrate to resist permeation of the copper-containing material to shorting electrical contact with the substrate. The penetration resistant amorphous layer permits a variety of processes to be used in forming the heterojunction with even very thin layers (1-6 mu thick) of underlying polycrystalline semi-conductor materials. In some embodiments, the amorphous-like structure may be formed by the addition of aluminum or zirconium compounds to a solution of cadmium salts sprayed over a heated substrate.

  16. Fuel cell arrangement

    DOEpatents

    Isenberg, Arnold O.

    1987-05-12

    A fuel cell arrangement is provided wherein cylindrical cells of the solid oxide electrolyte type are arranged in planar arrays where the cells within a plane are parallel. Planes of cells are stacked with cells of adjacent planes perpendicular to one another. Air is provided to the interior of the cells through feed tubes which pass through a preheat chamber. Fuel is provided to the fuel cells through a channel in the center of the cell stack; the fuel then passes the exterior of the cells and combines with the oxygen-depleted air in the preheat chamber.

  17. Fuel cell arrangement

    DOEpatents

    Isenberg, A.O.

    1987-05-12

    A fuel cell arrangement is provided wherein cylindrical cells of the solid oxide electrolyte type are arranged in planar arrays where the cells within a plane are parallel. Planes of cells are stacked with cells of adjacent planes perpendicular to one another. Air is provided to the interior of the cells through feed tubes which pass through a preheat chamber. Fuel is provided to the fuel cells through a channel in the center of the cell stack; the fuel then passes the exterior of the cells and combines with the oxygen-depleted air in the preheat chamber. 3 figs.

  18. Squamous cell carcinoma —

    Cancer.gov

    The hallmarks of squamous cell carcinoma are the differentiation features of the squamous epithelium: keratinization and intercellular bridges. Large central masses of keratin, individual cell keratinization, and/or keratin pearls may form. Necrosis of tumor cell nests and accumulation of acute inflammatory cells are frequent features of poorly differentiated squamous cell carcinoma.

  19. Sickle Cell Anemia

    MedlinePlus

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells are shaped like a crescent or sickle. They don' ... problem causes sickle cell anemia. People with the disease are born with two sickle cell genes, one ...

  20. Sickle Cell Anemia

    MedlinePlus

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells are shaped like a crescent or sickle. They ... last as long as normal, round red blood cells. This leads to anemia. The sickle cells also ...

  1. Virus Cell-to-Cell Transmission▿

    PubMed Central

    Mothes, Walther; Sherer, Nathan M.; Jin, Jing; Zhong, Peng

    2010-01-01

    Viral infections spread based on the ability of viruses to overcome multiple barriers and move from cell to cell, tissue to tissue, and person to person and even across species. While there are fundamental differences between these types of transmissions, it has emerged that the ability of viruses to utilize and manipulate cell-cell contact contributes to the success of viral infections. Central to the excitement in the field of virus cell-to-cell transmission is the idea that cell-to-cell spread is more than the sum of the processes of virus release and entry. This implies that virus release and entry are efficiently coordinated to sites of cell-cell contact, resulting in a process that is distinct from its individual components. In this review, we will present support for this model, illustrate the ability of viruses to utilize and manipulate cell adhesion molecules, and discuss the mechanism and driving forces of directional spreading. An understanding of viral cell-to-cell spreading will enhance our ability to intervene in the efficient spreading of viral infections. PMID:20375157

  2. Cell culture purity issues and DFAT cells

    SciTech Connect

    Wei, Shengjuan; Bergen, Werner G.; Zan, Linsen; Dodson, Michael V.

    2013-04-12

    Highlights: •DFAT cells are progeny cells derived from dedifferentiated mature adipocytes. •Common problems in this research is potential cell contamination of initial cultures. •The initial cell culture purity is crucial in DFAT cell research field. -- Abstract: Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  3. Deformability of Tumor Cells versus Blood Cells.

    PubMed

    Shaw Bagnall, Josephine; Byun, Sangwon; Begum, Shahinoor; Miyamoto, David T; Hecht, Vivian C; Maheswaran, Shyamala; Stott, Shannon L; Toner, Mehmet; Hynes, Richard O; Manalis, Scott R

    2015-01-01

    The potential for circulating tumor cells (CTCs) to elucidate the process of cancer metastasis and inform clinical decision-making has made their isolation of great importance. However, CTCs are rare in the blood, and universal properties with which to identify them remain elusive. As technological advancements have made single-cell deformability measurements increasingly routine, the assessment of physical distinctions between tumor cells and blood cells may provide insight into the feasibility of deformability-based methods for identifying CTCs in patient blood. To this end, we present an initial study assessing deformability differences between tumor cells and blood cells, indicated by the length of time required for them to pass through a microfluidic constriction. Here, we demonstrate that deformability changes in tumor cells that have undergone phenotypic shifts are small compared to differences between tumor cell lines and blood cells. Additionally, in a syngeneic mouse tumor model, cells that are able to exit a tumor and enter circulation are not required to be more deformable than the cells that were first injected into the mouse. However, a limited study of metastatic prostate cancer patients provides evidence that some CTCs may be more mechanically similar to blood cells than to typical tumor cell lines. PMID:26679988

  4. Deformability of Tumor Cells versus Blood Cells

    PubMed Central

    Shaw Bagnall, Josephine; Byun, Sangwon; Begum, Shahinoor; Miyamoto, David T.; Hecht, Vivian C.; Maheswaran, Shyamala; Stott, Shannon L.; Toner, Mehmet; Hynes, Richard O.; Manalis, Scott R.

    2015-01-01

    The potential for circulating tumor cells (CTCs) to elucidate the process of cancer metastasis and inform clinical decision-making has made their isolation of great importance. However, CTCs are rare in the blood, and universal properties with which to identify them remain elusive. As technological advancements have made single-cell deformability measurements increasingly routine, the assessment of physical distinctions between tumor cells and blood cells may provide insight into the feasibility of deformability-based methods for identifying CTCs in patient blood. To this end, we present an initial study assessing deformability differences between tumor cells and blood cells, indicated by the length of time required for them to pass through a microfluidic constriction. Here, we demonstrate that deformability changes in tumor cells that have undergone phenotypic shifts are small compared to differences between tumor cell lines and blood cells. Additionally, in a syngeneic mouse tumor model, cells that are able to exit a tumor and enter circulation are not required to be more deformable than the cells that were first injected into the mouse. However, a limited study of metastatic prostate cancer patients provides evidence that some CTCs may be more mechanically similar to blood cells than to typical tumor cell lines. PMID:26679988

  5. Red blood cells, multiple sickle cells (image)

    MedlinePlus

    ... inherited disorder in which abnormal hemoglobin (the red pigment inside red blood cells) is produced. The abnormal hemoglobin causes red blood cells to assume a sickle shape, like the ones seen in this photomicrograph.

  6. Fuel cell-fuel cell hybrid system

    DOEpatents

    Geisbrecht, Rodney A.; Williams, Mark C.

    2003-09-23

    A device for converting chemical energy to electricity is provided, the device comprising a high temperature fuel cell with the ability for partially oxidizing and completely reforming fuel, and a low temperature fuel cell juxtaposed to said high temperature fuel cell so as to utilize remaining reformed fuel from the high temperature fuel cell. Also provided is a method for producing electricity comprising directing fuel to a first fuel cell, completely oxidizing a first portion of the fuel and partially oxidizing a second portion of the fuel, directing the second fuel portion to a second fuel cell, allowing the first fuel cell to utilize the first portion of the fuel to produce electricity; and allowing the second fuel cell to utilize the second portion of the fuel to produce electricity.

  7. Cell Membrane Softening in Cancer Cells

    NASA Astrophysics Data System (ADS)

    Schmidt, Sebastian; Händel, Chris; Käs, Josef

    Biomechanical properties are useful characteristics and regulators of the cell's state. Current research connects mechanical properties of the cytoskeleton to many cellular processes but does not investigate the biomechanics of the plasma membrane. We evaluated thermal fluctuations of giant plasma membrane vesicles, directly derived from the plasma membranes of primary breast and cervical cells and observed a lowered rigidity in the plasma membrane of malignant cells compared to non-malignant cells. To investigate the specific role of membrane rigidity changes, we treated two cell lines with the Acetyl-CoA carboxylase inhibitor Soraphen A. It changed the lipidome of cells and drastically increased membrane stiffness by up regulating short chained membrane lipids. These altered cells had a decreased motility in Boyden chamber assays. Our results indicate that the thermal fluctuations of the membrane, which are much smaller than the fluctuations driven by the cytoskeleton, can be modulated by the cell and have an impact on adhesion and motility.

  8. Kidney cell electrophoresis

    NASA Technical Reports Server (NTRS)

    Todd, P.

    1980-01-01

    The following aspects of kidney cell electrophoresis are discussed: (1) the development and testing of electrophoresis solutions; (2) optimization of freezing and thawing; (3) procedures for evaluation of separated kidney cells; and (4) electrophoretic mobility characterization of kidney cells.

  9. Kidney cell electrophoresis

    NASA Technical Reports Server (NTRS)

    Todd, P.

    1979-01-01

    A kidney cell electrophoresis technique is described in four parts: (1) the development and testing of electrophoresis solutions; (2) optimization of freezing and thawing; (3) procedures for evaluation of separated kidney cells; and (4) electrophoretic mobility characteristics of kidney cells.

  10. Lung cancer - small cell

    MedlinePlus

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC ...

  11. Sickle Cell Information Center

    MedlinePlus

    ... change Sickle Cell News from Around the Web Google Custom Search – sickle cell Our healthcare system abandons ... professor of ... NYT, Nature, Wash Post, SciAm, CNN - Google Custom Search Sickle Cell Anemia News -- ScienceDaily January ...

  12. Lung cancer - small cell

    MedlinePlus

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  13. Fuel cells: A survey

    NASA Technical Reports Server (NTRS)

    Crowe, B. J.

    1973-01-01

    A survey of fuel cell technology and applications is presented. The operating principles, performance capabilities, and limitations of fuel cells are discussed. Diagrams of fuel cell construction and operating characteristics are provided. Photographs of typical installations are included.

  14. Advances in cell culture

    SciTech Connect

    Maramorosch, K. )

    1987-01-01

    This book presents papers on advances in cell culture. Topics covered include: Genetic changes in the influenza viruses during growth in cultured cells; The biochemistry and genetics of mosquito cells in culture; and Tree tissue culture applications.

  15. Sickle cell anemia - resources

    MedlinePlus

    Resources - sickle cell anemia ... The following organizations are good resources for information on sickle cell anemia : American Sickle Cell Anemia Association -- www.ascaa.org National Heart, Blood, and Lung Institute -- www. ...

  16. Reprogramming of somatic cells.

    PubMed

    Rajasingh, Johnson

    2012-01-01

    Reprogramming of adult somatic cells into pluripotent stem cells may provide an attractive source of stem cells for regenerative medicine. It has emerged as an invaluable method for generating patient-specific stem cells of any cell lineage without the use of embryonic stem cells. A revolutionary study in 2006 showed that it is possible to convert adult somatic cells directly into pluripotent stem cells by using a limited number of pluripotent transcription factors and is called as iPS cells. Currently, both genomic integrating viral and nonintegrating nonviral methods are used to generate iPS cells. However, the viral-based technology poses increased risk of safety, and more studies are now focused on nonviral-based technology to obtain autologous stem cells for clinical therapy. In this review, the pros and cons of the present iPS cell technology and the future direction for the successful translation of this technology into the clinic are discussed. PMID:22917226

  17. Inside the Cell

    MedlinePlus

    ... Business Basics Describes functions shared by virtually all cells: making fuel and proteins, transporting materials and disposing of wastes. » more Chapter 3: On the Job: Cellular Specialties Explains how cells specialize. Features a number of cell types: nerves, ...

  18. Closed Large Cell Clouds

    Atmospheric Science Data Center

    2013-04-19

    article title:  Closed Large Cell Clouds in the South Pacific     ... unperturbed by cyclonic or frontal activity. When the cell centers are cloudy and the main sinking motion is concentrated at cell ...

  19. Pancreatic islet cell tumor

    MedlinePlus

    Islet cell tumors; Islet of Langerhans tumor; Neuroendocrine tumors ... In the healthy pancreas, cells called islet cells produce hormones that regulate a several bodily functions. These include blood sugar level and the production of ...

  20. Sickle Cell Disease Quiz

    MedlinePlus

    ... False: People with sickle cell disease cannot get malaria. A True B False 4. True or False: ... False: People with sickle cell disease cannot get malaria. False People with sickle cell disease can get ...

  1. Glial cells: Old cells with new twists

    PubMed Central

    Ndubaku, Ugo; de Bellard, Maria Elena

    2008-01-01

    Summary Based on their characteristics and function – migration, neural protection, proliferation, axonal guidance and trophic effects – glial cells may be regarded as probably the most versatile cells in our body. For many years, these cells were considered as simply support cells for neurons. Recently, it has been shown that they are more versatile than previously believed – as true stem cells in the nervous system – and are important players in neural function and development. There are several glial cell types in the nervous system: the two most abundant are oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system. Although both of these cells are responsible for myelination, their developmental origins are quite different. Oligodendrocytes originate from small niche populations from different regions of the central nervous system, while Schwann cells develop from a stem cell population (the neural crest) that gives rise to many cell derivatives besides glia and which is a highly migratory group of cells. PMID:18068219

  2. CellFinder: a cell data repository

    PubMed Central

    Stachelscheid, Harald; Seltmann, Stefanie; Lekschas, Fritz; Fontaine, Jean-Fred; Mah, Nancy; Neves, Mariana; Andrade-Navarro, Miguel A.; Leser, Ulf; Kurtz, Andreas

    2014-01-01

    CellFinder (http://www.cellfinder.org) is a comprehensive one-stop resource for molecular data characterizing mammalian cells in different tissues and in different development stages. It is built from carefully selected data sets stemming from other curated databases and the biomedical literature. To date, CellFinder describes 3394 cell types and 50 951 cell lines. The database currently contains 3055 microscopic and anatomical images, 205 whole-genome expression profiles of 194 cell/tissue types from RNA-seq and microarrays and 553 905 protein expressions for 535 cells/tissues. Text mining of a corpus of >2000 publications followed by manual curation confirmed expression information on ∼900 proteins and genes. CellFinder’s data model is capable to seamlessly represent entities from single cells to the organ level, to incorporate mappings between homologous entities in different species and to describe processes of cell development and differentiation. Its ontological backbone currently consists of 204 741 ontology terms incorporated from 10 different ontologies unified under the novel CELDA ontology. CellFinder’s web portal allows searching, browsing and comparing the stored data, interactive construction of developmental trees and navigating the partonomic hierarchy of cells and tissues through a unique body browser designed for life scientists and clinicians. PMID:24304896

  3. Snail modulates cell metabolism in MDCK cells

    SciTech Connect

    Haraguchi, Misako; Indo, Hiroko P.; Iwasaki, Yasumasa; Iwashita, Yoichiro; Fukushige, Tomoko; Majima, Hideyuki J.; Izumo, Kimiko; Horiuchi, Masahisa; Kanekura, Takuro; Furukawa, Tatsuhiko; Ozawa, Masayuki

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  4. Sertoli cells as biochambers

    NASA Technical Reports Server (NTRS)

    Cameron, Don F. (Inventor); Sanberg, Paul R. (Inventor); Saporta, Samuel (Inventor); Hushen, Joelle J. (Inventor)

    2004-01-01

    According to the present invention, there is provided a biological chamber system having a biochamber defined by outer walls of Sertoli cells. Also provided is a transplantation facilitator including a biochamber. A method of making biochambers by co-culturing facilitator cells and therapeutic cells and then aggregating the facilitator celes is also provided. Also provided is a method of transplanting cells by incorporating transplant cells into a biochamber and transplanting the biochamber containing the transplant cells.

  5. Stem Cell Research

    SciTech Connect

    Verfaillie, Catherine

    2009-01-23

    We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

  6. Heterostructure solar cells

    NASA Technical Reports Server (NTRS)

    Chang, K. I.; Yeh, Y. C. M.; Iles, P. A.; Morris, R. K.

    1987-01-01

    The performance of gallium arsenide solar cells grown on Ge substrates is discussed. In some cases the substrate was thinned to reduce overall cell weight with good ruggedness. The conversion efficiency of 2 by 2 cm cells under AMO reached 17.1 percent with a cell thickness of 6 mils. The work described forms the basis for future cascade cell structures, where similar interconnecting problems between the top cell and the bottom cell must be solved. Applications of the GaAs/Ge solar cell in space and the expected payoffs are discussed.

  7. Stem Cell Research

    SciTech Connect

    Verfaillie, Catherine

    2002-01-23

    We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

  8. Gaucher cell, photomicrograph (image)

    MedlinePlus

    Gaucher's disease is called a "lipid storage disease" where abnormal amounts of lipids called "glycosphingolipids" are stored in special cells called reticuloendothelial cells. Classically, the nucleus is ...

  9. Cell heterogeneity during the cell cycle

    SciTech Connect

    Darzynkiewicz, Z.; Crissman, H.; Traganos, F.; Steinkamp, J.

    1982-12-01

    Using flow cytometry, populations of Chinese hamster ovary cells, asynchronous and synchronized in the cycle, were measured with respect to cellular RNA- and protein-content, as well as cell light scatter properties. Heterogeneities of cell populations were expressed as coefficients of variation (c.v.) in percent of the respective mean values. Populations of cells immediately after mitosis have about 15% higher c.v. than mitotic cell populations, regardless of whether RNA, proteins, or light scatter are measured. These data indicate that cytoplasmic constituents are unequally distributed into the daughter cells during cytokinesis and that unequal cytokinesis generates intercellular metabolic variability during the cycle. An additional increase in heterogeneity, although of smaller degree, occurs during G/sub 2/ phase. Populations of S-phase cells are the most uniform, having 20-30% lower c.v. than the postmitotic cells. Cell progression through S does not involve any significant increase in intercellular variability with respect to RNA or protein content. In unperturbed exponentially growing cultures a critical RNA content is required for G/sub 1/ cells prior to their entrance into S. The cell residence times in the equalization compartments are exponentially distributed, which may reflect the randomness generated by the uneven division of metabolic constituents to daughter cells during cytokinesis. The cell heterogeneities were presently estimated at two metabolic levels, transcription (RNA content) and translation (proteins). The most uniform were populations stained for RNA and the highest variability was observed after staining of proteins. This suggests that the regulatory mechanisms equalizing cells in the cell cycle may operate primarily at the level of DNA transcription.

  10. Stem cells supporting other stem cells

    PubMed Central

    Leatherman, Judith

    2013-01-01

    Adult stem cell therapies are increasingly prevalent for the treatment of damaged or diseased tissues, but most of the improvements observed to date are attributed to the ability of stem cells to produce paracrine factors that have a trophic effect on existing tissue cells, improving their functional capacity. It is now clear that this ability to produce trophic factors is a normal and necessary function for some stem cell populations. In vivo adult stem cells are thought to self-renew due to local signals from the microenvironment where they live, the niche. Several niches have now been identified which harbor multiple stem cell populations. In three of these niches – the Drosophila testis, the bulge of the mammalian hair follicle, and the mammalian bone marrow – one type of stem cell has been found to produce factors that contribute to the maintenance of a second stem cell population in the shared niche. In this review, I will examine the architecture of these three niches and discuss the molecular signals involved. Together, these examples establish a new paradigm for stem cell behavior, that stem cells can promote the maintenance of other stem cells. PMID:24348512

  11. Cell and tissue mechanics in cell migration

    PubMed Central

    Lange, Janina R.; Fabry, Ben

    2013-01-01

    Migrating cells generate traction forces to counteract the movement-resisting forces arising from cell-internal stresses and matrix adhesions. In the case of collective migration in a cell colony, or in the case of 3-dimensional migration through connective tissue, movement-resisting forces arise also from external stresses. Although the deformation of a stiffer cell or matrix causes larger movement-resisting forces, at the same time a larger stiffness can also promote cell migration due to a feedback between forces, deformations, and deformation speed that is mediated by the acto-myosin contractile machinery of cells. This mechanical feedback is also important for stiffness sensing, durotaxis, plithotaxis, and collective migration in cell colonies. PMID:23664834

  12. Cell and tissue mechanics in cell migration.

    PubMed

    Lange, Janina R; Fabry, Ben

    2013-10-01

    Migrating cells generate traction forces to counteract the movement-resisting forces arising from cell-internal stresses and matrix adhesions. In the case of collective migration in a cell colony, or in the case of 3-dimensional migration through connective tissue, movement-resisting forces arise also from external stresses. Although the deformation of a stiffer cell or matrix causes larger movement-resisting forces, at the same time a larger stiffness can also promote cell migration due to a feedback between forces, deformations, and deformation speed that is mediated by the acto-myosin contractile machinery of cells. This mechanical feedback is also important for stiffness sensing, durotaxis, plithotaxis, and collective migration in cell colonies. PMID:23664834

  13. Cancer stem cell-like cells from a single cell of oral squamous carcinoma cell lines

    SciTech Connect

    Felthaus, O.; Ettl, T.; Gosau, M.; Driemel, O.; Brockhoff, G.; Reck, A.; Zeitler, K.; Hautmann, M.; Reichert, T.E.; Schmalz, G.; Morsczeck, C.

    2011-04-01

    Research highlights: {yields} Four oral squamous cancer cell lines (OSCCL) were analyzed for cancer stem cells (CSCs). {yields} Single cell derived colonies of OSCCL express CSC-marker CD133 differentially. {yields} Monoclonal cell lines showed reduced sensitivity for Paclitaxel. {yields} In situ CD133{sup +} cells are slow cycling (Ki67-) indicating a reduced drug sensitivity. {yields} CD133{sup +} and CSC-like cells can be obtained from single colony forming cells of OSCCL. -- Abstract: Resistance of oral squamous cell carcinomas (OSCC) to conventional chemotherapy or radiation therapy might be due to cancer stem cells (CSCs). The development of novel anticancer drugs requires a simple method for the enrichment of CSCs. CSCs can be enriched from OSCC cell lines, for example, after cultivation in serum-free cell culture medium (SFM). In our study, we analyzed four OSCC cell lines for the presence of CSCs. CSC-like cells could not be enriched with SFM. However, cell lines obtained from holoclone colonies showed CSC-like properties such as a reduced rate of cell proliferation and a reduced sensitivity to Paclitaxel in comparison to cells from the parental lineage. Moreover, these cell lines differentially expressed the CSC-marker CD133, which is also upregulated in OSCC tissues. Interestingly, CD133{sup +} cells in OSCC tissues expressed little to no Ki67, the cell proliferation marker that also indicates reduced drug sensitivity. Our study shows a method for the isolation of CSC-like cell lines from OSCC cell lines. These CSC-like cell lines could be new targets for the development of anticancer drugs under in vitro conditions.

  14. Specific cell cycle synchronization with butyrate and cell cycle analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synchronized cells have been invaluable for many kinds of cell cycle and cell proliferation studies. Butyrate induces cell cycle arrest and apoptosis in MDBK cells. To explore the possibility of using butyrate-blocked cells to obtain synchronized cells, we investigated the property of the cell cyc...

  15. Stem cell therapy without the cells

    PubMed Central

    Maguire, Greg

    2013-01-01

    As an example of the burgeoning importance of stem cell therapy, this past month the California Institute for Regenerative Medicine (CIRM) has approved $70 million to create a new network of stem cell clinical trial centers. Much work in the last decade has been devoted to developing the use of autologous and allogeneic adult stem cell transplants to treat a number of conditions, including heart attack, dementia, wounds, and immune system-related diseases. The standard model teaches us that adult stem cells exists throughout most of the body and provide a means to regenerate and repair most tissues through replication and differentiation. Although we have often witnessed the medical cart placed in front of the scientific horse in the development of stem cell therapies outside of academic circles, great strides have been made, such as the use of purified stem cells1 instead of whole bone marrow transplants in cancer patients, where physicians avoid re-injecting the patients with their own cancer cells.2 We most often think of stem cell therapy acting to regenerate tissue through replication and then differentiation, but recent studies point to the dramatic effects adult stem cells exert in the repair of various tissues through the release of paracrine and autocrine substances, and not simply through differentiation. Indeed, up to 80% of the therapeutic effect of adult stem cells has been shown to be through paracrine mediated actions.3 That is, the collected types of molecules released by the stem cells, called the secretome, or stem cell released molecules (SRM), number in the 100s, including proteins, microRNA, growth factors, antioxidants, proteasomes, and exosomes, and target a multitude of biological pathways through paracrine actions. The composition of the different molecule types in SRM is state dependent, and varies with cell type and conditions such as age and environment. PMID:24567776

  16. Sickle Cell Disease

    MedlinePlus

    ... sickle cell disease? Sickle cell disease, also called sickle cell anemia, is a hereditary condition (which means it runs ... or blocks blood and oxygen reaching nearby tissues. Sickle cell disease ... the whites of the eyes) Anemia (the decreased ability of the blood to carry ...

  17. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    SciTech Connect

    Varga, Nora; Vereb, Zoltan; Rajnavoelgyi, Eva; Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs; Apati, Agota

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  18. SMOOTH MUSCLE STEM CELLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vascular smooth muscle cells (SMCs) originate from multiple types of progenitor cells. In the embryo, the most well-studied SMC progenitor is the cardiac neural crest stem cell. Smooth muscle differentiation in the neural crest lineage is controlled by a combination of cell intrinsic factors, includ...

  19. Nanocomposite Photoelectrochemical Cells

    NASA Technical Reports Server (NTRS)

    Narayan, Sri R.; Kindler, Andrew; Whitacre, Jay F.

    2007-01-01

    Improved, solid-state photoelectrochemical cells for converting solar radiation to electricity have been proposed. (In general, photoelectrochemical cells convert incident light to electricity through electrochemical reactions.) It is predicted that in comparison with state-of-the-art photoelectrochemical cells, these cells will be found to operate with greater solar-to-electric energy-conversion efficiencies.

  20. Fluorescence activated cell sorting.

    NASA Technical Reports Server (NTRS)

    Bonner, W. A.; Hulett, H. R.; Sweet, R. G.; Herzenberg, L. A.

    1972-01-01

    An instrument has been developed for sorting biological cells. The cells are rendered differentially fluorescent and incorporated into a small liquid stream illuminated by a laser beam. The cells pass sequentially through the beam, and fluorescent light from the cells gives rise to electrical signals. The stream is broken into a series of uniform size drops downstream of the laser. The cell signals are used to give appropriate electrostatic charges to drops containing the cells. The drops then pass between two charged plates and are deflected to appropriate containers. The system has proved capable of providing fractions containing large numbers of viable cells highly enriched in a particular functional type.

  1. Molten carbonate fuel cell

    DOEpatents

    Kaun, T.D.; Smith, J.L.

    1986-07-08

    A molten electrolyte fuel cell is disclosed with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas. The cell enclosures collectively provide an enclosure for the array and effectively avoid the problems of electrolyte migration and the previous need for compression of stack components. The fuel cell further includes an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

  2. Molten carbonate fuel cell

    DOEpatents

    Kaun, Thomas D.; Smith, James L.

    1987-01-01

    A molten electrolyte fuel cell with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas, the cell enclosures collectively providing an enclosure for the array and effectively avoiding the problems of electrolyte migration and the previous need for compression of stack components, the fuel cell further including an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

  3. Jameson cell coal flotation

    SciTech Connect

    Manlapig, E.V.; Jackson, B.R.; Harbort, G.J.; Cheng, C.Y.

    1993-12-31

    Jameson cells have been applied to coal flotation recent years. Some coal mines have Jameson cells in operation, some are having Jameson cells installed and others are considering to use Jameson cells in their flotation circuits. As an example, the application of Jameson cells in Newlands Coal Mine is described and the performance of the Jameson Cell is summarized. It has been demonstrated that the Jameson Cell performs well with minimum supervision and maintenance. The test work conducted at the University of Queensland and Blackwater Coal Mine has showed that the Jameson Cell performed consistently well at all testing conditions. The parallel tests have demonstrated that the Jameson Cell is superior over the conventional cells.

  4. Modeling collective cell motility

    NASA Astrophysics Data System (ADS)

    Rappel, Wouter-Jan

    Eukaryotic cells often move in groups, a critical aspect of many biological and medical processes including wound healing, morphogenesis and cancer metastasis. Modeling can provide useful insights into the fundamental mechanisms of collective cell motility. Constructing models that incorporate the physical properties of the cells, however, is challenging. Here, I discuss our efforts to build a comprehensive cell motility model that includes cell membrane properties, cell-substrate interactions, cell polarity, and cell-cell interaction. The model will be applied to a variety of systems, including motion on micropatterned substrates and the migration of border cells in Drosophila. This work was supported by NIH Grant No. P01 GM078586 and NSF Grant No. 1068869.

  5. Fuel cells seminar

    SciTech Connect

    1996-12-01

    This year`s meeting highlights the fact that fuel cells for both stationary and transportation applications have reached the dawn of commercialization. Sales of stationary fuel cells have grown steadily over the past 2 years. Phosphoric acid fuel cell buses have been demonstrated in urban areas. Proton-exchange membrane fuel cells are on the verge of revolutionizing the transportation industry. These activities and many more are discussed during this seminar, which provides a forum for people from the international fuel cell community engaged in a wide spectrum of fuel cell activities. Discussions addressing R&D of fuel cell technologies, manufacturing and marketing of fuel cells, and experiences of fuel cell users took place through oral and poster presentations. For the first time, the seminar included commercial exhibits, further evidence that commercial fuel cell technology has arrived. A total of 205 papers is included in this volume.

  6. Kidney cell electrophoresis

    NASA Technical Reports Server (NTRS)

    Todd, P. W.

    1985-01-01

    Tasks were undertaken in support of two objectives. They are: (1) to carry out electrophoresis experiments on cells in microgravity; and (2) assess the feasibility of using purified kidney cells from embryonic kidney cultures as a source of important cell products. Investigations were carried out in the following areas: (1) ground based electrophoresis technology; (2) cell culture technology; (3) electrophoresis of cells; (4) urokinase assay research; (5) zero-g electrophoresis; and (6) flow cytometry.

  7. Stem cell biobanks.

    PubMed

    Bardelli, Silvana

    2010-04-01

    Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment. PMID:20560026

  8. Technology Status: Fuel Cells and Electrolysis Cells

    NASA Technical Reports Server (NTRS)

    Mcbryar, H.

    1978-01-01

    The status of the baselined shuttle fuel cell as well as the acid membrane fuel cell and space-oriented water electrolysis technologies are presented. The more recent advances in the alkaline fuel cell technology area are the subject of a companion paper. A preliminary plan for the focusing of these technologies towards regenerative energy storage applications in the multi-hundred kilowatt range is also discussed.

  9. Screening of solar cells

    NASA Technical Reports Server (NTRS)

    Appelbaum, J.; Chait, A.; Thompson, D. A.

    1993-01-01

    Because solar cells in a production batch are not identical, screening is performed to obtain similar cells for aggregation into arrays. A common technique for screening is based on a single operating point of the I-V characteristic of the cell, usually the maximum power point. As a result, inferior cell matching may occur at the actual operating points. Screening solar cells based on the entire I-V characteristic will inherently result in more similar cells in the array. An array consisting of more similar cells is likely to have better overall characteristics and more predictable performance. Solar cell screening methods and cell ranking are discussed. The concept of a mean cell is defined as a cell 'best' representing all the cells in the production batch. The screening and ranking of all cells are performed with respect to the mean cell. The comparative results of different screening methods are illustrated on a batch of 50 silicon cells of the Space Station Freedom.

  10. Optimizing stem cell culture.

    PubMed

    van der Sanden, Boudewijn; Dhobb, Mehdi; Berger, François; Wion, Didier

    2010-11-01

    Stem cells always balance between self-renewal and differentiation. Hence, stem cell culture parameters are critical and need to be continuously refined according to progress in our stem cell biology understanding and the latest technological developments. In the past few years, major efforts have been made to define more precisely the medium composition in which stem cells grow or differentiate. This led to the progressive replacement of ill-defined additives such as serum or feeder cell layers by recombinant cytokines or growth factors. Another example is the control of the oxygen pressure. For many years cell cultures have been done under atmospheric oxygen pressure which is much higher than the one experienced by stem cells in vivo. A consequence of cell metabolism is that cell culture conditions are constantly changing. Therefore, the development of high sensitive monitoring processes and control algorithms is required for ensuring cell culture medium homeostasis. Stem cells also sense the physical constraints of their microenvironment. Rigidity, stiffness, and geometry of the culture substrate influence stem cell fate. Hence, nanotopography is probably as important as medium formulation in the optimization of stem cell culture conditions. Recent advances include the development of synthetic bioinformative substrates designed at the micro- and nanoscale level. On going research in many different fields including stem cell biology, nanotechnology, and bioengineering suggest that our current way to culture cells in Petri dish or flasks will soon be outdated as flying across the Atlantic Ocean in the Lindbergh's plane. PMID:20803548

  11. Screening of solar cells

    SciTech Connect

    Appelbaum, J.; Chait, A.; Thompson, D.A.

    1993-07-01

    Because solar cells in a production batch are not identical, screening is performed to obtain similar cells for aggregation into arrays. A common technique for screening is based on a single operating point of the I-V characteristic of the cell, usually the maximum power point. As a result, inferior cell matching may occur at the actual operating points. Screening solar cells based on the entire I-V characteristic will inherently result in more similar cells in the array. An array consisting of more similar cells is likely to have better overall characteristics and more predictable performance. Solar cell screening methods and cell ranking are discussed. The concept of a mean cell is defined as a cell 'best' representing all the cells in the production batch. The screening and ranking of all cells are performed with respect to the mean cell. The comparative results of different screening methods are illustrated on a batch of 50 silicon cells of the Space Station Freedom.

  12. Analytical pyrolysis of cells and cell fragments

    SciTech Connect

    Faix, O.; Bertelt, E.

    1995-12-01

    Wood of spruce, beech and birch was disintegrated without chemical pretreatment after 10 minutes of steaming at 110{degrees}C in a laboratory defibrator. Fibers, vessels, and fragments of secondary wall were separated by wet screening. A hydrocylon was used for separation of middle lamellae. By using analytical pyrolysis-GC/MS, parenchymatic cells were found to be richer in lignin than the other cells. The lignin content of middle lamellae was 35% (beech, spruce) and 39% (birch). In agreement with the literature, the S/G ratios of the vessels and middle lamellae was lower than those of the other cells and cell fragments.

  13. The cell biology of planar cell polarity

    PubMed Central

    2014-01-01

    Planar cell polarity (PCP) refers to the coordinated alignment of cell polarity across the tissue plane. Key to the establishment of PCP is asymmetric partitioning of cortical PCP components and intercellular communication to coordinate polarity between neighboring cells. Recent progress has been made toward understanding how protein transport, endocytosis, and intercellular interactions contribute to asymmetric PCP protein localization. Additionally, the functions of gradients and mechanical forces as global cues that bias PCP orientation are beginning to be elucidated. Together, these findings are shedding light on how global cues integrate with local cell interactions to organize cellular polarity at the tissue level. PMID:25349257

  14. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    NASA Astrophysics Data System (ADS)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  15. AB241. Cancer stem cell-like side population cells in clear cell renal cell carcinoma cell line 769P

    PubMed Central

    Huang, Bin; Wang, Dao-Hu; Chen, Jun-Xing; Qiu, Shao-Peng

    2016-01-01

    Background Although cancers are widely considered to be maintained by stem cells, the existence of stem cells in renal cell carcinoma (RCC) has seldom been reported, in part due to the lack of unique surface markers. We here identified cancer stem cell-like cells with side population (SP) phenotype in five human RCC cell lines. Methods We here identified cancer stem cell-like cells with side population (SP) phenotype in five human RCC cell lines. Results Flow cytometry analysis revealed that 769P, a human clear cell RCC cell line, contained the largest amount of SP cells among five cell lines. These 769P SP cells possessed characteristics of proliferation, self-renewal, and differentiation, as well as strong resistance to chemotherapy and radiotherapy that were possibly related to the ABCB1 transporter. In vivo experiments with serial tumor transplantation in mice also showed that 769P SP cells formed tumors in NOD/SCID mice. Conclusions Taken together, these results indicate that 769P SP cells have the properties of cancer stem cells, which may play important roles in tumorigenesis and therapy-resistance of RCC.

  16. Single cell mechanics of keratinocyte cells.

    PubMed

    Lulevich, Valentin; Yang, Hsin-ya; Isseroff, R Rivkah; Liu, Gang-yu

    2010-11-01

    Keratinocytes represent the major cell type of the uppermost layer of human skin, the epidermis. Using AFM-based single cell compression, the ability of individual keratinocytes to resist external pressure and global rupturing forces is investigated and compared with various cell types. Keratinocytes are found to be 6-70 times stiffer than other cell types, such as white blood, breast epithelial, fibroblast, or neuronal cells, and in contrast to other cell types they retain high mechanic strength even after the cell's death. The absence of membrane rupturing peaks in the force-deformation profiles of keratinocytes and their high stiffness during a second load cycle suggests that their unique mechanical resistance is dictated by the cytoskeleton. A simple analytical model enables the quantification of Young's modulus of keratinocyte cytoskeleton, as high as 120-340 Pa. Selective disruption of the two major cytoskeletal networks, actin filaments and microtubules, does not significantly affect keratinocyte mechanics. F-actin is found to impact cell deformation under pressure. During keratinocyte compression, the plasma membrane stretches to form peripheral blebs. Instead of blebbing, cells with depolymerized F-actin respond to pressure by detaching the plasma membrane from the cytoskeleton underneath. On the other hand, the compression force of keratinocytes expressing a mutated keratin (cell line, KEB-7) is 1.6-2.2 times less than that for the control cell line that has normal keratin networks. Therefore, we infer that the keratin intermediate filament network is responsible for the extremely high keratinocyte stiffness and resilience. This could manifest into the rugged protective nature of the human epidermis. PMID:20728993

  17. Plant stem cell niches.

    PubMed

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis. PMID:22404469

  18. Microscale Fuel Cells

    SciTech Connect

    Holladay, Jamie D.; Viswanathan, Vish V.

    2005-11-03

    Perhaprs some of the most innovative work on fuel cells has been the research dedicated to applying silicon fabrication techniques to fuel cells technology creating low power microscale fuel cells applicable to microelectro mechanical systems (MEMS), microsensors, cell phones, PDA’s, and other low power (0.001 to 5 We) applications. In this small power range, fuel cells offer the decoupling of the energy converter from the energy storage which may enable longer operating times and instant or near instant charging. To date, most of the microscale fuel cells being developed have been based on proton exchange membrane fuel cell technology (PEMFC) or direct methanol fuel cell (DMFC) technology. This section will discuss requirements and considerations that need to be addressed in the development of microscale fuel cells, as well as some proposed designs and fabrication strategies.

  19. Tetraspanins in Cell Migration

    PubMed Central

    Jiang, Xupin; Zhang, Jiaping; Huang, Yuesheng

    2015-01-01

    Tetraspanins are a superfamily of small transmembrane proteins that are expressed in almost all eukaryotic cells. Through interacting with one another and with other membrane and intracellular proteins, tetraspanins regulate a wide range of proteins such as integrins, cell surface receptors, and signaling molecules, and thereby engage in diverse cellular processes ranging from cell adhesion and migration to proliferation and differentiation. In particular, tetraspanins modulate the function of proteins involved in all determining factors of cell migration including cell–cell adhesion, cell–ECM adhesion, cytoskeletal protrusion/contraction, and proteolytic ECM remodeling. We herein provide a brief overview of collective in vitro and in vivo studies of tetraspanins to illustrate their regulatory functions in the migration and trafficking of cancer cells, vascular endothelial cells, skin cells (keratinocytes and fibroblasts), and leukocytes. We also discuss the involvement of tetraspanins in various pathologic and remedial processes that rely on cell migration and their potential value as targets for therapeutic intervention. PMID:26091149

  20. Bacterial Cell Wall Components

    NASA Astrophysics Data System (ADS)

    Ginsberg, Cynthia; Brown, Stephanie; Walker, Suzanne

    Bacterial cell-surface polysaccharides cells are surrounded by a variety of cell-surface structures that allow them to thrive in extreme environments. Components of the cell envelope and extracellular matrix are responsible for providing the cells with structural support, mediating intercellular communication, allowing the cells to move or to adhere to surfaces, protecting the cells from attack by antibiotics or the immune system, and facilitating the uptake of nutrients. Some of the most important cell wall components are polysaccharide structures. This review discusses the occurrence, structure, function, and biosynthesis of the most prevalent bacterial cell surface polysaccharides: peptidoglycan, lipopolysaccharide, arabinogalactan, and lipoarabinomannan, and capsular and extracellular polysaccharides. The roles of these polysaccharides in medicine, both as drug targets and as therapeutic agents, are also described.

  1. Aquaporins and cell migration.

    PubMed

    Papadopoulos, M C; Saadoun, S; Verkman, A S

    2008-07-01

    Aquaporin (AQP) water channels are expressed primarily in cell plasma membranes. In this paper, we review recent evidence that AQPs facilitate cell migration. AQP-dependent cell migration has been found in a variety of cell types in vitro and in mice in vivo. AQP1 deletion reduces endothelial cell migration, limiting tumor angiogenesis and growth. AQP4 deletion slows the migration of reactive astrocytes, impairing glial scarring after brain stab injury. AQP1-expressing tumor cells have enhanced metastatic potential and local infiltration. Impaired cell migration has also been seen in AQP1-deficient proximal tubule epithelial cells, and AQP3-deficient corneal epithelial cells, enterocytes, and skin keratinocytes. The mechanisms by which AQPs enhance cell migration are under investigation. We propose that, as a consequence of actin polymerization/depolymerization and transmembrane ionic fluxes, the cytoplasm adjacent to the leading edge of migrating cells undergoes rapid changes in osmolality. AQPs could thus facilitate osmotic water flow across the plasma membrane in cell protrusions that form during migration. AQP-dependent cell migration has potentially broad implications in angiogenesis, tumor metastasis, wound healing, glial scarring, and other events requiring rapid, directed cell movement. AQP inhibitors may thus have therapeutic potential in modulating these events, such as slowing tumor growth and spread, and reducing glial scarring after injury to allow neuronal regeneration. PMID:17968585

  2. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    PubMed Central

    Liu, Quanwen; Shen, Yi; Chen, Jiarong; Ding, Jie; Tang, Zihua; Zhang, Cui; Chen, Jianling; Li, Liang; Chen, Ping; Wang, Jinfu

    2016-01-01

    In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bundles. The hair-cell-like cells exhibited rapid permeation of FM1-43FX. The whole-cell patch-clamp technique was used to measure the membrane currents of cells differentiated for 7 days on chicken utricle stromal cells and analyze the biophysical properties of the hair-cell-like cells by recording membrane properties of cells. The results suggested that the hair-cell-like cells derived from inner ear multipotent cells were functional following differentiation in an enabling environment. PMID:27057177

  3. Lithium cell test results

    NASA Technical Reports Server (NTRS)

    Bragg, B. J.

    1977-01-01

    Three lithium SO2 cells, two lithium CF cells, and a vinyl chloride cell, all with crimped seals, and all strictly experimental, were independently discharged on resistors. Three temperatures were used and several different storage temperatures. Discharge rate generally on the nominal discharges were 0.1 amp, 0.5 amp, and 1 amp. Tests results show that the crimp seals are inadequate, especially for the SO2 cells. Normal discharges present no hazards. All cells discharge to zero. The problem of lithium cell explosions, such as occurred during off-limits testing, is discussed.

  4. Cell adhesion force microscopy

    PubMed Central

    Sagvolden, G.; Giaever, I.; Pettersen, E. O.; Feder, J.

    1999-01-01

    The adhesion forces of cervical carcinoma cells in tissue culture were measured by using the manipulation force microscope, a novel atomic force microscope. The forces were studied as a function of time and temperature for cells cultured on hydrophilic and hydrophobic polystyrene substrates with preadsorbed proteins. The cells attached faster and stronger at 37°C than at 23°C and better on hydrophilic than on hydrophobic substrates, even though proteins adsorb much better to the hydrophobic substrates. Because cell adhesion serves to control several stages in the cell cycle, we anticipate that the manipulation force microscope can help clarify some cell-adhesion related issues. PMID:9892657

  5. Hydrogen/bromine cell

    SciTech Connect

    Hohne, K.; Starbeck, G.

    1985-05-28

    Described herein is an energy storage device which utilizes a hydrogen/bromine cell. The cell includes a bromine electrode and a hydrogen electrode. The cell is light weight, resists corrosion caused by bromine or hydrobromic acid and uses both an electrolysis and a fuel cell reaction to store or discharge electrical energy. The cell frame is made of graphite and has a pyrographite coating on at least the portion facing the bromine electrode. This cell is therefore very useful in matching varying energy supplies with varying energy demands and allows for decentralization of energy storage.

  6. On cells and size

    NASA Astrophysics Data System (ADS)

    Boudaoud, Arezki

    2002-03-01

    The growth of isolated cells is studied. They are modeled as growing elastic shells submitted to an internal pressure. A scaling law for a preferred radius of curvature is derived. It is in agreement with compiled experimental data over more than orders of magnitude in cell radia (for elongated cells from bacteria to giant algae cells). The physical picture is that a cell grow spherically until the preferred radius and then elongate into a cylindrical tube to keep the preferred curvature, except if a cell division occurs. A simplification of the model is investigated more quantitavely.

  7. Solar cell activation system

    SciTech Connect

    Apelian, L.

    1983-07-05

    A system for activating solar cells involves the use of phosphorescent paint, the light from which is amplified by a thin magnifying lens and used to activate solar cells. In a typical system, a member painted with phosphorescent paint is mounted adjacent a thin magnifying lens which focuses the light on a predetermined array of sensitive cells such as selenium, cadmium or silicon, mounted on a plastic board. A one-sided mirror is mounted adjacent the cells to reflect the light back onto said cells for purposes of further intensification. The cells may be coupled to rechargeable batteries or used to directly power a small radio or watch.

  8. Assessment of pancreas cells

    NASA Technical Reports Server (NTRS)

    Vanoss, C. J.

    1978-01-01

    Pancreatic islets were obtained from guinea pig pancreas by the collagenase method and kept alive in tissue culture prior to further studies. Pancreas cell morphology was studied by standard histochemical techniques using light microscopy. Preparative vertical electrophoresis-levitation of dispersed fetal guinea pig pancreas cells was conducted in phosphate buffer containing a heavy water (D20) gradient which does not cause clumping of cells or alter the osmolarity of the buffers. The faster migrating fractions tended to be enriched in beta-cell content. Alpha and delta cells were found to some degree in most fractions. A histogram showing the cell count distribution is included.

  9. Are mesenchymal stromal cells immune cells?

    PubMed

    Hoogduijn, Martin J

    2015-01-01

    Mesenchymal stromal cells (MSCs) are considered to be promising agents for the treatment of immunological disease. Although originally identified as precursor cells for mesenchymal lineages, in vitro studies have demonstrated that MSCs possess diverse immune regulatory capacities. Pre-clinical models have shown beneficial effects of MSCs in multiple immunological diseases and a number of phase 1/2 clinical trials carried out so far have reported signs of immune modulation after MSC infusion. These data indicate that MSCs play a central role in the immune response. This raises the academic question whether MSCs are immune cells or whether they are tissue precursor cells with immunoregulatory capacity. Correct understanding of the immunological properties and origin of MSCs will aid in the appropriate and safe use of the cells for clinical therapy. In this review the whole spectrum of immunological properties of MSCs is discussed with the aim of determining the position of MSCs in the immune system. PMID:25880839

  10. Germ cell binding to rat Sertoli cells in vitro

    SciTech Connect

    DePhilip, R.M.; Danahey, D.G.

    1987-12-01

    The interaction between male germ cells and Sertoli cells was studied in vitro by co-incubation experiments using isolated rat germ cells and primary cultures of Sertoli cells made germ cell-free by the differential sensitivity of germ cells to hypotonic shock. The germ cell/Sertoli cell interaction was examined morphologically with phase-contrast and scanning electron microscopy and then quantified by measuring radioactivity bound to Sertoli cell cultures after co-incubation with added (/sup 3/H)leucine-labeled germ cells. Germ cell binding to Sertoli cell cultures was the result of specific adhesion between these two cell types, and several features of this specific adhesion were observed. First, germ cells adhered to Sertoli cell cultures under conditions during which spleen cells and red blood cells did not. Second, germ cells had a greater affinity for Sertoli cell cultures than they had for cultures of testicular peritubular cells or cerebellar astrocytes. Third, germ cells fixed with paraformaldehyde adhered to live Sertoli cultures while similarly fixed spleen cells adhered less tightly. Neither live nor paraformaldehyde-fixed germ cells adhered to fixed Sertoli cell cultures. Fourth, germ cell binding to Sertoli cell cultures was not immediate but increased steadily and approached a maximum at 4 h of co-incubation. Saturation of germ cell binding to Sertoli cell cultures occurred when more than 4200 germ cells were added per mm2 of Sertoli cell culture surface. Finally, germ cell binding to Sertoli cell cultures was eliminated when co-incubation was performed on ice. Based on these observations, we concluded that germ cell adhesion to Sertoli cells was specific, temperature-dependent, and required a viable Sertoli cell but not necessarily a viable germ cell.

  11. Single-cell growth analysis in a mixed cell culture

    NASA Astrophysics Data System (ADS)

    Ando, Jun; Bato, Mary Grace P.; Daria, Vincent Ricardo

    2008-06-01

    We perform single cell analysis of cell growth in a mixed cell culture. Two species of yeast cells: Saccharomyces cerevisiae and Candida albicans, are optically trapped using focused continuous-wave near infrared laser. Cell growth for both cells is inhibited only when the two species of cells are in contact with each other. This indicates cell-cell interaction mediated cell growth inhibition mechanism. Single cell level analysis of cell growth studied here contributes to the further understanding of yeast growth arrest in a mixed yeast culture.

  12. Mesenchymal stem cells for cardiac cell therapy.

    PubMed

    Choi, Yeong-Hoon; Kurtz, Andreas; Stamm, Christof

    2011-01-01

    Despite refinements of medical and surgical therapies, heart failure remains a fatal disease. Myocardial infarction is the most common cause of heart failure, and only palliative measures are available to relieve symptoms and prolong the patient's life span. Because mammalian cardiomyocytes irreversibly exit the cell cycle at about the time of birth, the heart has traditionally been considered to lack any regenerative capacity. This paradigm, however, is currently shifting, and the cellular composition of the myocardium is being targeted by various regeneration strategies. Adult progenitor and stem cell treatment of diseased human myocardium has been carried out for more than 10 years (Menasche et al., 2001; Stamm et al., 2003), and it has become clear that, in humans, the regenerative capacity of hematopoietic stem cells and endothelial progenitor cells, despite potent proangiogenic effects, is limited (Stamm et al., 2009). More recently, mesenchymal stem cells (MSCs) and related cell types are being evaluated in preclinical models of heart disease as well as in clinical trials (see Published Clinical Trials, below). MSCs have the capacity to self-renew and to differentiate into lineages that normally originate from the embryonic mesenchyme (connective tissues, blood vessels, blood-related organs) (Caplan, 1991; Prockop, 1997; Pittenger et al., 1999). The current definition of MSCs includes plastic adherence in cell culture, specific surface antigen expression (CD105(+)/CD90(+)/CD73(+), CD34(-)/CD45(-)/CD11b(-) or CD14(-)/CD19(-) or CD79α(-)/HLA-DR1(-)), and multilineage in vitro differentiation potential (osteogenic, chondrogenic, and adipogenic) (Dominici et al., 2006 ). If those criteria are not met completely, the term "mesenchymal stromal cells" should be used for marrow-derived adherent cells, or other terms for MSC-like cells of different origin. For the purpose of this review, MSCs and related cells are discussed in general, and cell type

  13. What Are Islet Cells?

    MedlinePlus

    ... Derived Stem Cells MichCanSka 2010 Benefits DRI Wounded Soldier Gets Standing Ovation Video New Website Launches Journal ... Derived Stem Cells MichCanSka 2010 Benefits DRI Wounded Soldier Gets Standing Ovation Video New Website Launches Journal ...

  14. Fluorescence Live Cell Imaging

    PubMed Central

    Ettinger, Andreas

    2014-01-01

    Fluorescence microscopy of live cells has become an integral part of modern cell biology. Fluorescent protein tags, live cell dyes, and other methods to fluorescently label proteins of interest provide a range of tools to investigate virtually any cellular process under the microscope. The two main experimental challenges in collecting meaningful live cell microscopy data are to minimize photodamage while retaining a useful signal-to-noise ratio, and to provide a suitable environment for cells or tissues to replicate physiological cell dynamics. This chapter aims to give a general overview on microscope design choices critical for fluorescence live cell imaging that apply to most fluorescence microscopy modalities, and on environmental control with a focus on mammalian tissue culture cells. In addition, we provide guidance on how to design and evaluate fluorescent protein constructs by spinning disk confocal microscopy. PMID:24974023

  15. Sickle Cell Trait

    MedlinePlus

    ... About Us Information For... Media Policy Makers Sickle Cell Trait Language: English Español (Spanish) Recommend on Facebook ... the trait on to their children. How Sickle Cell Trait is Inherited If both parents have SCT, ...

  16. Toward 'SMART' stem cells.

    PubMed

    Cheng, T

    2008-01-01

    Stem cell research is at the heart of regenerative medicine, which holds great promise for the treatment of many devastating disorders. However, in addition to hurdles posed by well-publicized ethical issues, this emerging field presents many biological challenges. What is a stem cell? How are embryonic stem cells different from adult stem cells? What are the physiological bases for therapeutically acceptable stem cells? In this editorial review, I will briefly discuss these superficially simple but actually rather complex issues that surround this fascinating cell type. The goal of this special issue on stem cells in Gene Therapy is to review some fundamental and critical aspects of current stem cell research that have translational potential. PMID:18046429

  17. Antiparietal cell antibody test

    MedlinePlus

    ... Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; Vitamin B12 - anti- ... may use this test to help diagnose pernicious anemia. Pernicious anemia is a decrease in red blood ...

  18. Cell-SELEX Technology.

    PubMed

    Ohuchi, Shoji

    2012-12-01

    Aptamers are molecules identified from large combinatorial nucleic acid libraries by their high affinity to target molecules. Due to a variety of desired properties, aptamers are attractive alternatives to antibodies in molecular biology and medical applications. Aptamers are identified through an iterative selection-amplification process known as systematic evolution of ligands by exponential enrichment (SELEX). Although SELEX is typically carried out using purified target molecules, whole live cells are also employable as selection targets. This technology, Cell-SELEX, has several advantages. For example, generated aptamers are functional with a native conformation of the target molecule on live cells, and thus, cell surface transmembrane proteins would be targets even when their purifications in native conformations are difficult. In addition, cell-specific aptamers can be obtained without any knowledge about cell surface molecules on the target cells. Here, I review the progress of Cell-SELEX technology and discuss advantages of the technology. PMID:23515081

  19. Squamous Cell Carcinoma (SCC)

    MedlinePlus

    ... A A Squamous cell carcinoma typically develops in sun-damaged skin in fair-skinned patients. Overview Squamous ... skin cancer. Squamous cell carcinoma usually occurs on sun-damaged skin, especially in light-skinned individuals with ...

  20. Sickle Cell Disease

    MedlinePlus

    ... Overview of CDC’s work. Advancements in Sickle Cell Disease New supplement from the American Journal of Preventive Medicine describes the state of sickle cell disease related care in the United States. Read Supplement ...

  1. White Blood Cell Count

    MedlinePlus

    ... Home Visit Global Sites Search Help? White Blood Cell Count Share this page: Was this page helpful? Also ... Leukocyte Count; White Count Formal name: White Blood Cell Count Related tests: Complete Blood Count , Blood Smear , White ...

  2. Basal Cell Carcinoma (BCC)

    MedlinePlus

    ... carcinomas: Infiltrating basal cell carcinomas can be more aggressive and locally destructive than other types of basal ... to treat them early and with slightly more aggressive techniques. Excision – The basal cell carcinoma is cut ...

  3. Giant Cell Arteritis

    MedlinePlus

    Giant cell arteritis is a disorder that causes inflammation of your arteries, usually in the scalp, neck, and arms. ... arteries, which keeps blood from flowing well. Giant cell arteritis often occurs with another disorder called polymyalgia ...

  4. Closed Small Cell Clouds

    Atmospheric Science Data Center

    2013-04-19

    article title:  Closed Small Cell Clouds in the South Pacific     ... the Multi-angle Imaging SpectroRadiometer (MISR). Closed cell clouds are formed under conditions of widespread sinking of the air above. ...

  5. Kidney Cell Electrophoresis

    NASA Technical Reports Server (NTRS)

    Todd, P.

    1985-01-01

    Materials and procedures for microgravity electrophoresis of living human embryonic kidney cells were evaluated, ground support in the form of analytical cell electrophoresis and flow cytometry was provided and cells returned from space flight were analyzed. Preflight culture media, electrophoresis buffer, fraction collection media, temperature profiles, and urokinase assay procedures were tested prior to flight. Electrophoretic mobility distributions of aliquots of the cell population to be fractionated in flight were obtained. The protocol established and utilized is given.

  6. Increased voltage photovoltaic cell

    NASA Technical Reports Server (NTRS)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  7. [Hairy cell leukemia].

    PubMed

    Dietrich, S; Andrulis, M; Zenz, T

    2015-04-01

    Hairy cell leukemia was initially described as a distinct entity in 1958. It is rare B-cell malignancy characterized by an indolent course. Advances in the treatment and understanding of the biology of hairy cell leukemia have made the disease exquisitely amenable to treatment. This review summarizes the present understanding of hairy cell leukemia with a particular focus on the development of novel and targeted approaches to treatment. PMID:25787322

  8. Regenerative fuel cells

    NASA Technical Reports Server (NTRS)

    Swette, Larry L.; Kackley, Nancy D.; Laconti, Anthony B.

    1992-01-01

    A development status evaluation is presented for moderate-temperature, single-unit, regenerative fuel cells using either alkaline or solid polymer proton-exchange membrane (PEM) electrolytes. Attention is given to the results thus far obtained for Pt, Ir, Rh, and Na(x)Pt3O4 catalysts. Alkaline electrolyte tests have been performed on a half-cell basis with a floating-electrode cell; PEM testing has been with complete fuel cells, using Nafion 117.

  9. Fuel cells feasibility

    NASA Technical Reports Server (NTRS)

    Schonfeld, D.; Charng, T.

    1981-01-01

    The technical and economic status of fuel cells is assessed with emphasis on their potential benefits to the Deep Space Network. The fuel cell, what it is, how it operates, and what its outputs are, is reviewed. Major technical problems of the fuel cell and its components are highlighted. Due to these problems and economic considerations it is concluded that fuel cells will not become commercially viable until the early 1990s.

  10. Stem Cell Research.

    PubMed

    Trounson, Alan; Kolaja, Kyle; Petersen, Thomas; Weber, Klaus; McVean, Maralee; Funk, Kathleen A

    2015-01-01

    Stem cells have great potential in basic research and are being slowly integrated into toxicological research. This symposium provided an overview of the state of the field, stem cell models, described allogenic stem cell treatments and issues of immunogenicity associated with protein therapeutics, and tehn concentrated on stem cell uses in regenerative medicine focusing on lung and testing strategies on engineered tissues from a pathologist's perspective. PMID:25899720

  11. Diagram of Cell to Cell Communication

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  12. Endothelial cells enhance migration of meniscus cells

    PubMed Central

    Yuan, Xiaoning; Eng, George M.; Arkonac, Derya E.; Chao, Pen-hsiu Grace; Vunjak-Novakovic, Gordana

    2014-01-01

    Objective To study the interactions between vascular endothelial cells and meniscal fibrochondrocytes from the inner avascular and outer vascular regions of the meniscus, and identify angiogenic factors that enhance cell migration and integrative repair. Methods Bovine meniscal fibrochondrocytes (bMFCs) from the inner and outer regions of meniscus were cultured for seven days with and without human umbilical vein endothelial cells (HUVECs) in a micropatterned three-dimensional hydrogel system for cell migration. Angiogenic factors secreted by HUVECs were probed for their role in paracrine mechanisms governing bMFC migration, and applied to a full-thickness defect model of meniscal repair in explants from the inner and outer regions over four weeks. Results Endothelial cells enhanced migration of inner and outer bMFCs in the micropatterned system via endothelin-1 (ET-1) signaling. Supplementation of ET-1 significantly enhanced integration strength of full-thickness defects in inner and outer explants, and cell migration at the macro-scale, compared to controls without ET-1 treatment. Conclusion We report for the first time that bMFCs from both the avascular and vascular regions respond to the presence of endothelial cells with increased migration. Paracrine signaling by endothelial cells regulates the bMFCs differentially by region, but we identify ET-1 as an angiogenic factor that stimulates migration of inner and outer cells at the micro-scale, and integrative repair of inner and outer explants at the macro-scale. These findings reveal the regional interactions between vasculature and MFCs, and suggest ET-1 as a potential new treatment modality for avascular meniscal injuries, in order to prevent the development of osteoarthritis. PMID:25307081

  13. Molecular Mechanisms of HTLV-1 Cell-to-Cell Transmission

    PubMed Central

    Gross, Christine; Thoma-Kress, Andrea K.

    2016-01-01

    The tumorvirus human T-cell lymphotropic virus type 1 (HTLV-1), a member of the delta-retrovirus family, is transmitted via cell-containing body fluids such as blood products, semen, and breast milk. In vivo, HTLV-1 preferentially infects CD4+ T-cells, and to a lesser extent, CD8+ T-cells, dendritic cells, and monocytes. Efficient infection of CD4+ T-cells requires cell-cell contacts while cell-free virus transmission is inefficient. Two types of cell-cell contacts have been described to be critical for HTLV-1 transmission, tight junctions and cellular conduits. Further, two non-exclusive mechanisms of virus transmission at cell-cell contacts have been proposed: (1) polarized budding of HTLV-1 into synaptic clefts; and (2) cell surface transfer of viral biofilms at virological synapses. In contrast to CD4+ T-cells, dendritic cells can be infected cell-free and, to a greater extent, via viral biofilms in vitro. Cell-to-cell transmission of HTLV-1 requires a coordinated action of steps in the virus infectious cycle with events in the cell-cell adhesion process; therefore, virus propagation from cell-to-cell depends on specific interactions between cellular and viral proteins. Here, we review the molecular mechanisms of HTLV-1 transmission with a focus on the HTLV-1-encoded proteins Tax and p8, their impact on host cell factors mediating cell-cell contacts, cytoskeletal remodeling, and thus, virus propagation. PMID:27005656

  14. Cell phones and cancer

    MedlinePlus

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of exposure ...

  15. Biomarkers of cell senescence

    DOEpatents

    Dimri, G.P.; Campisi, J.; Peacocke, M.

    1998-08-18

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, {beta}-galactosidase activity is utilized as a means by which cell senescence may be assessed either in vitro cell cultures or in vivo. 1 fig.

  16. Biomarkers of cell senescence

    DOEpatents

    Dirmi, G.P.; Campisi, J.; Peacocke, M.

    1996-02-13

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, {beta}-galactosidase activity is utilized as a means by which cell senescence may be assessed either in in vitro cell cultures or in vivo. 1 fig.

  17. Mammalian Cell Culture Simplified.

    ERIC Educational Resources Information Center

    Moss, Robert; Solomon, Sondra

    1991-01-01

    A tissue culture experiment that does not require elaborate equipment and that can be used to teach sterile technique, the principles of animal cell line maintenance, and the concept of cell growth curves is described. The differences between cancerous and normal cells can be highlighted. The procedure is included. (KR)

  18. Plasma Cell Disorders

    MedlinePlus

    ... microorganisms to which the body is exposed. In plasma cell disorders, one clone of plasma cells multiplies uncontrollably. As a result, this clone ... a light chain and heavy chain). These abnormal plasma cells and the ... produce are limited to one type, and levels of other types of antibodies ...

  19. Solar Photovoltaic Cells.

    ERIC Educational Resources Information Center

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  20. Pancreas Cell Fate

    PubMed Central

    Guney, Michelle A.; Gannon, Maureen

    2009-01-01

    Diabetes is characterized by decreased function of insulin-producing insulin β cells and insufficient insulin output resulting from an absolute (Type 1) or relative (Type 2) inadequate functional β cell mass. Both forms of the disease would greatly benefit from treatment strategies that could enhance β cell regeneration and/or function. Successful and reliable methods of generatingβ cells or whole islets from progenitor cells in vivo or in vitro could lead to restoration of β cell mass in individuals with Type 1 diabetes and enhanced β cell compensation in Type 2 patients. A thorough understanding of the normal developmental processes that occur during pancreatic organogenesis, e.g., transcription factors, cell signaling molecules, and cell-cell interactions that regulate endocrine differentiation from the embryonic pancreatic epithelium, is required in order to successfully reach these goals. This review summarizes our current understanding of pancreas development, with particular emphasis on factors intrinsic or extrinsic to the pancreatic epithelium that are involved in regulating the development and differentiation of the various pancreatic cell types. We also discuss the recent progress in generating insulin-producing cells from progenitor sources. PMID:19750517

  1. Red blood cell production

    MedlinePlus

    ... cells are an important element of blood. Their job is to transport oxygen to the body’s tissues in exchange for carbon dioxide, which is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts ...

  2. Photoelectrochemical Solar Cells.

    ERIC Educational Resources Information Center

    McDevitt, John T.

    1984-01-01

    This introduction to photoelectrochemical (PEC) cells reviews topics pertaining to solar energy conversion and demonstrates the ease with which a working PEC cell can be prepared with n-type silicon as the photoanode and a platinum counter electrode (both immersed in ethanolic ferrocene/ferricenium solutions). Experiments using the cell are…

  3. Solar cell device

    SciTech Connect

    Nishiura, M.; Haruki, H.; Miyagi, M.; Sakai, H.; Uchida, Y.

    1984-06-26

    A solar cell array is equipped with serially or parallel connected reverse polarity diodes formed simultaneously with the array. The diodes are constituted by one or more solar cells of the array which may be shaded to prevent photoelectric conversion, and which are electrically connected in reverse polarity with respect to the remaining cells.

  4. Biomarkers of cell senescence

    DOEpatents

    Dirmi, Goberdhan P.; Campisi, Judith; Peacocke, Monica

    1996-01-01

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, .beta.-galactosidase activity is utilized as a means by which cell senescence may be assessed either in in vitro cell cultures or in vivo.

  5. Biomarkers of cell senescence

    DOEpatents

    Dimri, Goberdhan P.; Campisi, Judith; Peacocke, Monica

    1998-01-01

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, .beta.-galactosidase activity is utilized as a means by which cell senescence may be assessed either in vitro cell cultures or in vivo.

  6. Cell Culture Made Easy.

    ERIC Educational Resources Information Center

    Dye, Frank J.

    1985-01-01

    Outlines steps to generate cell samples for observation and experimentation. The procedures (which use ordinary laboratory equipment) will establish a short-term primary culture of normal mammalian cells. Information on culture vessels and cell division and a list of questions to generate student interest and involvement in the topics are…

  7. Mast cells and inflammation.

    PubMed

    Theoharides, Theoharis C; Alysandratos, Konstantinos-Dionysios; Angelidou, Asimenia; Delivanis, Danae-Anastasia; Sismanopoulos, Nikolaos; Zhang, Bodi; Asadi, Shahrzad; Vasiadi, Magdalini; Weng, Zuyi; Miniati, Alexandra; Kalogeromitros, Dimitrios

    2012-01-01

    Mast cells are well known for their role in allergic and anaphylactic reactions, as well as their involvement in acquired and innate immunity. Increasing evidence now implicates mast cells in inflammatory diseases where they are activated by non-allergic triggers, such as neuropeptides and cytokines, often exerting synergistic effects as in the case of IL-33 and neurotensin. Mast cells can also release pro-inflammatory mediators selectively without degranulation. In particular, IL-1 induces selective release of IL-6, while corticotropin-releasing hormone secreted under stress induces the release of vascular endothelial growth factor. Many inflammatory diseases involve mast cells in cross-talk with T cells, such as atopic dermatitis, psoriasis and multiple sclerosis, which all worsen by stress. How mast cell differential responses are regulated is still unresolved. Preliminary evidence suggests that mitochondrial function and dynamics control mast cell degranulation, but not selective release. Recent findings also indicate that mast cells have immunomodulatory properties. Understanding selective release of mediators could explain how mast cells participate in numerous diverse biologic processes, and how they exert both immunostimulatory and immunosuppressive actions. Unraveling selective mast cell secretion could also help develop unique mast cell inhibitors with novel therapeutic applications. This article is part of a Special Issue entitled: Mast cells in inflammation. PMID:21185371

  8. Cell phones and cancer

    MedlinePlus

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of ...

  9. Adventures with Cell Phones

    ERIC Educational Resources Information Center

    Kolb, Liz

    2011-01-01

    Teachers are finding creative ways to turn the basic cell phone from a digital distraction into a versatile learning tool. In this article, the author explains why cell phones are important in learning and suggests rather than banning them that they be integrated into learning. She presents activities that can be done on a basic cell phone with a…

  10. Stochastic elimination of cancer cells.

    PubMed Central

    Michor, Franziska; Nowak, Martin A; Frank, Steven A; Iwasa, Yoh

    2003-01-01

    Tissues of multicellular organisms consist of stem cells and differentiated cells. Stem cells divide to produce new stem cells or differentiated cells. Differentiated cells divide to produce new differentiated cells. We show that such a tissue design can reduce the rate of fixation of mutations that increase the net proliferation rate of cells. It has, however, no consequence for the rate of fixation of neutral mutations. We calculate the optimum relative abundance of stem cells that minimizes the rate of generating cancer cells. There is a critical fraction of stem cell divisions that is required for a stochastic elimination ('wash out') of cancer cells. PMID:14561289

  11. Microfluidic fuel cells

    NASA Astrophysics Data System (ADS)

    Kjeang, Erik

    Microfluidic fuel cell architectures are presented in this thesis. This work represents the mechanical and microfluidic portion of a microfluidic biofuel cell project. While the microfluidic fuel cells developed here are targeted to eventual integration with biocatalysts, the contributions of this thesis have more general applicability. The cell architectures are developed and evaluated based on conventional non-biological electrocatalysts. The fuel cells employ co-laminar flow of fuel and oxidant streams that do not require a membrane for physical separation, and comprise carbon or gold electrodes compatible with most enzyme immobilization schemes developed to date. The demonstrated microfluidic fuel cell architectures include the following: a single cell with planar gold electrodes and a grooved channel architecture that accommodates gaseous product evolution while preventing crossover effects; a single cell with planar carbon electrodes based on graphite rods; a three-dimensional hexagonal array cell based on multiple graphite rod electrodes with unique scale-up opportunities; a single cell with porous carbon electrodes that provides enhanced power output mainly attributed to the increased active area; a single cell with flow-through porous carbon electrodes that provides improved performance and overall energy conversion efficiency; and a single cell with flow-through porous gold electrodes with similar capabilities and reduced ohmic resistance. As compared to previous results, the microfluidic fuel cells developed in this work show improved fuel cell performance (both in terms of power density and efficiency). In addition, this dissertation includes the development of an integrated electrochemical velocimetry approach for microfluidic devices, and a computational modeling study of strategic enzyme patterning for microfluidic biofuel cells with consecutive reactions.

  12. Cell adhesion molecules involved in intrathymic T cell development.

    PubMed

    Patel, D D; Haynes, B F

    1993-08-01

    During stem cell migration to the thymus, intrathymic maturation of T cells, and emigration of mature T cells out of the thymus, intercellular interactions of developing T cells with a myriad of cell types are required for normal T cell development. Intercellular interactions of T cell precursors with endothelial cells, thymic epithelial cells, fibroblasts, thymic macrophages and dendritic cells are all mediated by adhesion molecules on immature T cells binding to ligands on thymic microenvironment cells. While many receptor-ligand interactions that are important in intrathymic T cell development are known, the adhesion molecules that are important for migration of T cell precursors to the thymus and for emigration of mature thymocytes from the thymus are poorly understood. An emerging concept is that select adhesion molecules at discrete stages of T cell maturation participate in and regulate the complex processes of T cell development. PMID:7693023

  13. Regulation of Th2 Cell Immunity by Dendritic Cells

    PubMed Central

    Na, Hyeongjin

    2016-01-01

    Th2 cell immunity is required for host defense against helminths, but it is detrimental in allergic diseases in humans. Unlike Th1 cell and Th17 cell subsets, the mechanism by which dendritic cells modulate Th2 cell responses has been obscure, in part because of the inability of dendritic cells to provide IL-4, which is indispensable for Th2 cell lineage commitment. In this regard, immune cells other than dendritic cells, such as basophils and innate lymphoid cells, have been suggested as Th2 cell inducers. More recently, multiple independent researchers have shown that specialized subsets of dendritic cells mediate Th2 cell responses. This review will discuss the current understanding related to the regulation of Th2 cell responses by dendritic cells and other immune cells. PMID:26937227

  14. Leukemia - B-Cell Prolymphocytic Leukemia and Hairy Cell Leukemia

    MedlinePlus

    ... Leukemia: Introduction Request Permissions Print to PDF Leukemia - B-cell Prolymphocytic Leukemia and Hairy Cell Leukemia: Introduction ... Research and Advocacy Survivorship Blog About Us Leukemia - B-cell Prolymphocytic Leukemia and Hairy Cell Leukemia Guide ...

  15. Fuel Cell Handbook update

    SciTech Connect

    Owens, W.R.; Hirschenhofer, J.H.; Engleman, R.R. Jr.; Stauffer, D.B.

    1993-11-01

    The objective of this work was to update the 1988 version of DOE`s Fuel Cell Handbook. Significant developments in the various fuel cell technologies required revisions to reflect state-of-the-art configurations and performance. The theoretical presentation was refined in order to make the handbook more useful to both the casual reader and fuel cell or systems analyst. In order to further emphasize the practical application of fuel cell technologies, the system integration information was expanded. In addition, practical elements, such as suggestions and guidelines to approximate fuel cell performance, were provided.

  16. Skeletal muscle satellite cells

    NASA Technical Reports Server (NTRS)

    Schultz, E.; McCormick, K. M.

    1994-01-01

    Evidence now suggests that satellite cells constitute a class of myogenic cells that differ distinctly from other embryonic myoblasts. Satellite cells arise from somites and first appear as a distinct myoblast type well before birth. Satellite cells from different muscles cannot be functionally distinguished from one another and are able to provide nuclei to all fibers without regard to phenotype. Thus, it is difficult to ascribe any significant function to establishing or stabilizing fiber type, even during regeneration. Within a muscle, satellite cells exhibit marked heterogeneity with respect to their proliferative behavior. The satellite cell population on a fiber can be partitioned into those that function as stem cells and those which are readily available for fusion. Recent studies have shown that the cells are not simply spindle shaped, but are very diverse in their morphology and have multiple branches emanating from the poles of the cells. This finding is consistent with other studies indicating that the cells have the capacity for extensive migration within, and perhaps between, muscles. Complexity of cell shape usually reflects increased cytoplasmic volume and organelles including a well developed Golgi, and is usually associated with growing postnatal muscle or muscles undergoing some form of induced adaptive change or repair. The appearance of activated satellite cells suggests some function of the cells in the adaptive process through elaboration and secretion of a product. Significant advances have been made in determining the potential secretion products that satellite cells make. The manner in which satellite cell proliferative and fusion behavior is controlled has also been studied. There seems to be little doubt that cellcell coupling is not how satellite cells and myofibers communicate. Rather satellite cell regulation is through a number of potential growth factors that arise from a number of sources. Critical to the understanding of this form

  17. Making Ultrathin Solar Cells

    NASA Technical Reports Server (NTRS)

    Cogan, George W.; Christel, Lee A.; Merchant, J. Thomas; Gibbons, James F.

    1991-01-01

    Process produces extremely thin silicon solar cells - only 50 micrometers or less in thickness. Electrons and holes have less opportunity to recombine before collected at cell surfaces. Efficiency higher and because volume of silicon small, less chance of radiation damage in new cells. Initial steps carried out at normal thickness to reduce breakage and avoid extra cost of special handling. Cells then thinned mechanically and chemically. Final cell includes reflective layer on back surface. Layer bounces unabsorbed light back into bulk silicon so it absorbs and produces useful electrical output.

  18. Transparent ultraviolet photovoltaic cells.

    PubMed

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future. PMID:26872163

  19. Fuel Cell Handbook update

    NASA Astrophysics Data System (ADS)

    Owens, W. R.; Hirschenhofer, J. H.; Engleman, R. R., Jr.; Stauffer, D. B.

    The objective of this work was to update the 1988 version of DOE's Fuel Cell Handbook. Significant developments in the various fuel cell technologies required revisions to reflect state-of-the-art configurations and performance. The theoretical presentation was refined in order to make the handbook more useful to both the casual reader and fuel cell or systems analyst. In order to further emphasize the practical application of fuel cell technologies, the system integration information was expanded. In addition, practical elements, such as suggestions and guidelines to approximate fuel cell performance, were provided.

  20. Place Cells, Grid Cells, Attractors, and Remapping

    PubMed Central

    Jeffery, Kathryn J.

    2011-01-01

    Place and grid cells are thought to use a mixture of external sensory information and internal attractor dynamics to organize their activity. Attractor dynamics may explain both why neurons react coherently following sufficiently large changes to the environment (discrete attractors) and how firing patterns move smoothly from one representation to the next as an animal moves through space (continuous attractors). However, some features of place cell behavior, such as the sometimes independent responsiveness of place cells to environmental change (called “remapping”), seem hard to reconcile with attractor dynamics. This paper suggests that the explanation may be found in an anatomical separation of the two attractor systems coupled with a dynamic contextual modulation of the connection matrix between the two systems, with new learning being back-propagated into the matrix. Such a scheme could explain how place cells sometimes behave coherently and sometimes independently. PMID:22135756

  1. Fuel Cell/Electrochemical Cell Voltage Monitor

    NASA Technical Reports Server (NTRS)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  2. Mast cells and inflammation

    PubMed Central

    Theoharides, Theoharis C.; Alysandratos, Konstantinos-Dionysios; Angelidou, Asimenia; Delivanis, Danae-Anastasia; Sismanopoulos, Nikolaos; Zhang, Bodi; Asadi, Shahrzad; Vasiadi, Magdalini; Weng, Zuyi; Miniati, Alexandra; Kalogeromitros, Dimitrios

    2012-01-01

    Mast cells are well known for their role in allergic and anaphylactic reactions, as well as their involvement in acquired and innate immunity. Increasing evidence now implicates mast cells in inflammatory diseases where they are activated by non-allergic triggers, such as neuropeptides and cytokines, often exerting synergistic effects as in the case of IL-33. Mast cells can also release pro-inflammatory mediators selectively without degranulation. In particular, IL-1 induces selective release of IL-6, while corticotropin-releasing hormone secreted under stress induces the release of vascular endothelial growth factor. Many inflammatory diseases involve mast cells in cross-talk with T cells, such as atopic dermatitis, psoriasis and multiple sclerosis, which all worsen by stress. How mast cell differential responses are regulated is still unresolved. Preliminary evidence suggests that mitochondrial function and dynamics control mast cell degranulation, but not selective release. Recent findings also indicate that mast cells have immunomodulatory properties. Understanding selective release of mediators could explain how mast cells participate in numerous diverse biologic processes, and how they exert both immunostimulatory and immunosuppressive actions. Unraveling selective mast cell secretion could also help develop unique mast cell inhibitors with novel therapeutic applications. PMID:21185371

  3. Parameterization of solar cells

    NASA Astrophysics Data System (ADS)

    Appelbaum, J.; Chait, A.; Thompson, D.

    1992-10-01

    The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided by modeling the cell using an equivalent electrical circuit, in which the parameters involved are related to the physical phenomena in the device. These analytical models may be represented by a double exponential I-V characteristic with seven parameters, by a double exponential model with five parameters, or by a single exponential equation with four or five parameters. In this article we address issues concerning methodologies for the determination of solar cell parameters based on measured data points of the I-V characteristic, and introduce a procedure for screening of solar cells for arrays. We show that common curve fitting techniques, e.g., least squares, may produce many combinations of parameter values while maintaining a good fit between the fitted and measured I-V characteristics of the cell. Therefore, techniques relying on curve fitting criteria alone cannot be directly used for cell parameterization. We propose a consistent procedure which takes into account the entire set of parameter values for a batch of cells. This procedure is based on a definition of a mean cell representing the batch, and takes into account the relative contribution of each parameter to the overall goodness of fit. The procedure is demonstrated on a batch of 50 silicon cells for Space Station Freedom.

  4. Electroporation of cell membranes.

    PubMed

    Tsong, T Y

    1991-08-01

    Electric pulses of intensity in kilovolts per centimeter and of duration in microseconds to milliseconds cause a temporary loss of the semipermeability of cell membranes, thus leading to ion leakage, escape of metabolites, and increased uptake by cells of drugs, molecular probes, and DNA. A generally accepted term describing this phenomenon is "electroporation." Other effects of a high-intensity electric field on cell membranes include membrane fusions, bleb formation, cell lysis... etc. Electroporation and its related phenomena reflect the basic bioelectrochemistry of cell membranes and are thus important for the study of membrane structure and function. These phenomena also occur in such events as electric injury, electrocution, and cardiac procedures involving electric shocks. Electroporation has found applications in: (a) introduction of plasmids or foreign DNA into living cells for gene transfections, (b) fusion of cells to prepare heterokaryons, hybridoma, hybrid embryos... etc., (c) insertion of proteins into cell membranes, (d) improving drug delivery and hence effectiveness in chemotherapy of cancerous cells, (e) constructing animal model by fusing human cells with animal tissues, (f) activation of membrane transporters and enzymes, and (g) alteration of genetic expression in living cells. A brief review of mechanistic studies of electroporation is given. PMID:1912274

  5. Electroporation of cell membranes.

    PubMed Central

    Tsong, T Y

    1991-01-01

    Electric pulses of intensity in kilovolts per centimeter and of duration in microseconds to milliseconds cause a temporary loss of the semipermeability of cell membranes, thus leading to ion leakage, escape of metabolites, and increased uptake by cells of drugs, molecular probes, and DNA. A generally accepted term describing this phenomenon is "electroporation." Other effects of a high-intensity electric field on cell membranes include membrane fusions, bleb formation, cell lysis... etc. Electroporation and its related phenomena reflect the basic bioelectrochemistry of cell membranes and are thus important for the study of membrane structure and function. These phenomena also occur in such events as electric injury, electrocution, and cardiac procedures involving electric shocks. Electroporation has found applications in: (a) introduction of plasmids or foreign DNA into living cells for gene transfections, (b) fusion of cells to prepare heterokaryons, hybridoma, hybrid embryos... etc., (c) insertion of proteins into cell membranes, (d) improving drug delivery and hence effectiveness in chemotherapy of cancerous cells, (e) constructing animal model by fusing human cells with animal tissues, (f) activation of membrane transporters and enzymes, and (g) alteration of genetic expression in living cells. A brief review of mechanistic studies of electroporation is given. PMID:1912274

  6. Stress and stem cells.

    PubMed

    Tower, John

    2012-01-01

    The unique properties and functions of stem cells make them particularly susceptible to stresses and also lead to their regulation by stress. Stem cell division must respond to the demand to replenish cells during normal tissue turnover as well as in response to damage. Oxidative stress, mechanical stress, growth factors, and cytokines signal stem cell division and differentiation. Many of the conserved pathways regulating stem cell self-renewal and differentiation are also stress-response pathways. The long life span and division potential of stem cells create a propensity for transformation (cancer) and specific stress responses such as apoptosis and senescence act as antitumor mechanisms. Quiescence regulated by CDK inhibitors and a hypoxic niche regulated by FOXO transcription factor function to reduce stress for several types of stem cells to facilitate long-term maintenance. Aging is a particularly relevant stress for stem cells, because repeated demands on stem cell function over the life span can have cumulative cell-autonomous effects including epigenetic dysregulation, mutations, and telomere erosion. In addition, aging of the organism impairs function of the stem cell niche and systemic signals, including chronic inflammation and oxidative stress. PMID:23799624

  7. Follicular Helper T Cells.

    PubMed

    Vinuesa, Carola G; Linterman, Michelle A; Yu, Di; MacLennan, Ian C M

    2016-05-20

    Although T cell help for B cells was described several decades ago, it was the identification of CXCR5 expression by B follicular helper T (Tfh) cells and the subsequent discovery of their dependence on BCL6 that led to the recognition of Tfh cells as an independent helper subset and accelerated the pace of discovery. More than 20 transcription factors, together with RNA-binding proteins and microRNAs, control the expression of chemotactic receptors and molecules important for the function and homeostasis of Tfh cells. Tfh cells prime B cells to initiate extrafollicular and germinal center antibody responses and are crucial for affinity maturation and maintenance of humoral memory. In addition to the roles that Tfh cells have in antimicrobial defense, in cancer, and as HIV reservoirs, regulation of these cells is critical to prevent autoimmunity. The realization that follicular T cells are heterogeneous, comprising helper and regulatory subsets, has raised questions regarding a possible division of labor in germinal center B cell selection and elimination. PMID:26907215

  8. Parameterization of solar cells

    NASA Technical Reports Server (NTRS)

    Appelbaum, J.; Chait, A.; Thompson, D.

    1992-01-01

    The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided by modeling the cell using an equivalent electrical circuit, in which the parameters involved are related to the physical phenomena in the device. These analytical models may be represented by a double exponential I-V characteristic with seven parameters, by a double exponential model with five parameters, or by a single exponential equation with four or five parameters. In this article we address issues concerning methodologies for the determination of solar cell parameters based on measured data points of the I-V characteristic, and introduce a procedure for screening of solar cells for arrays. We show that common curve fitting techniques, e.g., least squares, may produce many combinations of parameter values while maintaining a good fit between the fitted and measured I-V characteristics of the cell. Therefore, techniques relying on curve fitting criteria alone cannot be directly used for cell parameterization. We propose a consistent procedure which takes into account the entire set of parameter values for a batch of cells. This procedure is based on a definition of a mean cell representing the batch, and takes into account the relative contribution of each parameter to the overall goodness of fit. The procedure is demonstrated on a batch of 50 silicon cells for Space Station Freedom.

  9. T cell subpopulations.

    PubMed

    Romagnani, Sergio

    2014-01-01

    The role of allergen-specific CD4+ effector type 2 helper (Th2) cells in the pathogenesis of allergic disorders is an established fact. Th2 cells produce interleukin (IL)-4 and IL-13, which induce immunoglobulin E production by B cells, and IL-5 that allows recruitment of eosinophils. Two main mechanisms control the Th2-mediated allergic inflammation: immune deviation (or Th1 redirection) and immune regulation. Regulatory T (Treg) cells exhibit a CD4+ phenotype and include Foxp3-positive thymic and induced Tregs, as well as Foxp3-negative IL-10-producing cells. Both immune deviation and immune regulation evoked by the maternal and newborn microbial environment probably operate in preventing allergen-specific Th2 responses. However, microbe-related protection from allergy seems to mainly depend on epigenetically controlled acetylation of the IFNG promoter of CD4+ T cells. Even Th17 and Th9 cells, as well as invariant NKT cells, have been implicated in the pathogenesis of allergic disorders, but their role is certainly more limited. Recently, innate lymphoid type 2 cells (ILC2) have been found to be able to produce high amounts of IL-5 and IL-13 in response to stimulation with IL-25 and IL-33 produced by non-immune cells. Together with Th2 cells, ILC2 may contribute to the induction and maintenance of allergic inflammation. PMID:24925396

  10. Protrusive Activity Guides Changes in Cell-Cell Tension during Epithelial Cell Scattering

    PubMed Central

    Maruthamuthu, Venkat; Gardel, Margaret L.

    2014-01-01

    Knowing how epithelial cells regulate cell-matrix and cell-cell adhesions is essential to understand key events in morphogenesis as well as pathological events such as metastasis. During epithelial cell scattering, epithelial cell islands rupture their cell-cell contacts and migrate away as single cells on the extracellular matrix (ECM) within hours of growth factor stimulation, even as adhesion molecules such as E-cadherin are present at the cell-cell contact. How the stability of cell-cell contacts is modulated to effect such morphological transitions is still unclear. Here, we report that in the absence of ECM, E-cadherin adhesions continue to sustain substantial cell-generated forces upon hepatocyte growth factor (HGF) stimulation, consistent with undiminished adhesion strength. In the presence of focal adhesions, constraints that preclude the spreading and movement of cells at free island edges also prevent HGF-mediated contact rupture. To explore the role of cell motion and cell-cell contact rupture, we examine the biophysical changes that occur during the scattering of cell pairs. We show that the direction of cell movement with respect to the cell-cell contact is correlated with changes in the average intercellular force as well as the initial direction of cell-cell contact rupture. Our results suggest an important role for protrusive activity resulting in cell displacement and force redistribution in guiding cell-cell contact rupture during scattering. PMID:25099795

  11. T Cells Going Innate.

    PubMed

    Seyda, Midas; Elkhal, Abdallah; Quante, Markus; Falk, Christine S; Tullius, Stefan G

    2016-08-01

    Natural killer (NK) cell receptors (NKRs) play a crucial role in the homeostasis of antigen-experienced T cells. Indeed, prolonged antigen stimulation may induce changes in the receptor repertoire of T cells to a profile that features NKRs. Chronic antigen exposure, at the same time, has been shown to trigger the loss of costimulatory CD28 molecules with recently reported intensified antigen thresholds of antigen-experienced CD8(+) T cells. In transplantation, NKRs have been shown to assist allograft rejection in a CD28-independent fashion. We discuss here a role for CD28-negative T cells that have acquired the competency of the NKR machinery, potentially promoting allorecognition either through T cell receptor (TCR) crossreactivity or independently from TCR recognition. Collectively, NKRs can bring about innate-like T cells by providing alternative costimulatory pathways that gain relevance in chronic inflammation, potentially leading to resistance to CD28-targeting immunosuppressants. PMID:27402226

  12. Microbial sensor cell arrays.

    PubMed

    Melamed, Sahar; Elad, Tal; Belkin, Shimshon

    2012-02-01

    Motivated by the advantages endowed by high-throughput analysis, researchers have succeeded in incorporating multiple reporter cells into a single platform; the technology now allows the simultaneous scrutiny of a large collection of sensor strains. We review current aspects in cell array technology with emphasis on microbial sensor arrays. We consider various techniques for patterning live cells on solid surfaces, describe different array-based applications and devices, and highlight recent efforts for live cell storage. We review mathematical approaches for deciphering the data emanating from bioreporter collections, and discuss the future of single cell arrays. Innovative technologies for cell patterning, preservation and interpretation are continuously being developed; when they all mature, cell arrays may become an efficient analytical tool, in a scope resembling that of DNA microarray biochips. PMID:22176747

  13. Cell Differentiation and Checkpoint

    PubMed Central

    Sancho, Sara Cuesta; Ouchi, Toru

    2015-01-01

    DNA damage is induced in many types of cells by internal and external cell stress. When DNA is damaged, DNA Damage Response (DDR) programs are activated to repair the DNA lesions in order to preserve genomic integrity and suppress subsequent malignant transformation. Among these programs is cell cycle checkpoint that ensures cell cycle arrest and subsequent repair of the damaged DNA, apoptosis and senescence in various phases of the cell cycle. Moreover, recent studies have established the cell differentiation checkpoint, the other type of the checkpoint that is specifically activated in the course of differentiation. We will discuss the evidences that support the link between DNA damage proteins and C2C12 cell differentiation. PMID:26998525

  14. Cell sorting apparatus

    NASA Technical Reports Server (NTRS)

    Yen, Shiao-Ping S. (Inventor); Rembaum, Alan (Inventor); Molday, Robert S. (Inventor)

    1980-01-01

    Polymeric functional microspheres containing metal or metal compounds are formed by addition polymerization of a covalently bondable olefinic monomer such as hydroxyethylmethacrylate in the presence of finely divided metal or metal oxide particles, such as iron, gold, platinum or magnetite, which are embedded in the resulting microspheres. The microspheres can be covalently bonded to chemotherapeutic agents, antibodies, or other proteins providing a means for labeling or separating labeled cells. Labeled cells or microspheres can be concentrated at a specific body location such as in the vicinity of a malignant tumor by applying a magnetic field to the location and then introducing the magnetically attractable microspheres or cells into the circulatory system of the subject. Labeled cells can be separated from a cell mixture by applying a predetermined magnetic field to a tube in which the mixture is flowing. After collection of the labeled cells, the magnetic field is discontinued and the labeled sub-cell population recovered.

  15. Intraoperative Stem Cell Therapy

    PubMed Central

    Coelho, Mónica Beato; Cabral, Joaquim M.S.; Karp, Jeffrey M.

    2013-01-01

    Stem cells hold significant promise for regeneration of tissue defects and disease-modifying therapies. Although numerous promising stem cell approaches are advancing in clinical trials, intraoperative stem cell therapies offer more immediate hope by integrating an autologous cell source with a well-established surgical intervention in a single procedure. Herein, the major developments in intraoperative stem cell approaches, from in vivo models to clinical studies, are reviewed, and the potential regenerative mechanisms and the roles of different cell populations in the regeneration process are discussed. Although intraoperative stem cell therapies have been shown to be safe and effective for several indications, there are still critical challenges to be tackled prior to adoption into the standard surgical armamentarium. PMID:22809140

  16. Natural killer cell deficiency

    PubMed Central

    Orange, Jordan S.

    2013-01-01

    Natural killer (NK) cells are part of the innate immune defense against infection and cancer, and are especially useful in combating certain viral pathogens. The utility of NK cells in human health has been underscored by a growing number of individuals who are deficient in NK cells and/or their functions. This can be in the context of a broader genetically-defined congenital immunodeficiency of which there are over forty presently known to impair NK cells. The abnormality of NK cells, however, in certain cases represents the majority immunological defect. In aggregate, these conditions are termed NK cell deficiency. Recent advances have added clarity to this diagnosis and identified defects in three different genes that can cause NK cell deficiency as well as some of the underlying biology. Appropriate consideration of these diagnoses and patients raises the potential for rational therapeutic options and further innovation. PMID:23993353

  17. Cell wall integrity

    PubMed Central

    Pogorelko, Gennady; Lionetti, Vincenzo; Bellincampi, Daniela; Zabotina, Olga

    2013-01-01

    The plant cell wall, a dynamic network of polysaccharides and glycoproteins of significant compositional and structural complexity, functions in plant growth, development and stress responses. In recent years, the existence of plant cell wall integrity (CWI) maintenance mechanisms has been demonstrated, but little is known about the signaling pathways involved, or their components. Examination of key mutants has shed light on the relationships between cell wall remodeling and plant cell responses, indicating a central role for the regulatory network that monitors and controls cell wall performance and integrity. In this review, we present a short overview of cell wall composition and discuss post-synthetic cell wall modification as a valuable approach for studying CWI perception and signaling pathways. PMID:23857352

  18. Tuning cell fate

    PubMed Central

    Kami, Daisuke; Gojo, Satoshi

    2014-01-01

    Epigenetic interventions are required to induce reprogramming from one cell type to another. At present, various cellular reprogramming methods such as somatic cell nuclear transfer, cell fusion, and direct reprogramming using transcription factors have been reported. In particular, direct reprogramming from somatic cells to induced pluripotent stem cells (iPSCs) has been achieved using defined factors that play important epigenetic roles. Although the mechanisms underlying cellular reprogramming and vertebrate regeneration, including appendage regeneration, remain unknown, dedifferentiation occurs at an early phase in both the events, and both events are contrasting with regard to cell death. We compared the current status of changes in cell fate of iPSCs with that of vertebrate regeneration and suggested that substantial insights into vertebrate regeneration should be helpful for safe applications of iPSCs to medicine. PMID:24736602

  19. Involvement of Plant Stem Cells or Stem Cell-Like Cells in Dedifferentiation

    PubMed Central

    Jiang, Fangwei; Feng, Zhenhua; Liu, Hailiang; Zhu, Jian

    2015-01-01

    Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells) are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation. PMID:26635851

  20. Sickle Cell Crisis (Pain Crisis)

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Sickle Cell Crisis (Pain Crisis) KidsHealth > For Teens > Sickle Cell ... A A A Text Size What Is a Sickle Cell Crisis? Sickle cell disease changes the shape of ...

  1. Membrane Cells for Brine Electrolysis.

    ERIC Educational Resources Information Center

    Tingle, M.

    1982-01-01

    Membrane cells were developed as alternatives to mercury and diaphragm cells for the electrolysis of brine. Compares the three types of cells, focusing on the advantages and disadvantages of membrane cells. (JN)

  2. Information on Stem Cell Research

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS Information on Stem Cell Research Research @ NINDS Stem Cell Highlights Submit a hESC ... found here: Human Induced Pluripotent Stem Cells NINDS Stem Cell Research on Campus The Intramural Research Program of NINDS ...

  3. Nestin(+) cells direct inflammatory cell migration in atherosclerosis.

    PubMed

    Del Toro, Raquel; Chèvre, Raphael; Rodríguez, Cristina; Ordóñez, Antonio; Martínez-González, José; Andrés, Vicente; Méndez-Ferrer, Simón

    2016-01-01

    Atherosclerosis is a leading death cause. Endothelial and smooth muscle cells participate in atherogenesis, but it is unclear whether other mesenchymal cells contribute to this process. Bone marrow (BM) nestin(+) cells cooperate with endothelial cells in directing monocyte egress to bloodstream in response to infections. However, it remains unknown whether nestin(+) cells regulate inflammatory cells in chronic inflammatory diseases, such as atherosclerosis. Here, we show that nestin(+) cells direct inflammatory cell migration during chronic inflammation. In Apolipoprotein E (ApoE) knockout mice fed with high-fat diet, BM nestin(+) cells regulate the egress of inflammatory monocytes and neutrophils. In the aorta, nestin(+) stromal cells increase ∼30 times and contribute to the atheroma plaque. Mcp1 deletion in nestin(+) cells-but not in endothelial cells only- increases circulating inflammatory cells, but decreases their aortic infiltration, delaying atheroma plaque formation and aortic valve calcification. Therefore, nestin expression marks cells that regulate inflammatory cell migration during atherosclerosis. PMID:27586429

  4. Functional interplay between the cell cycle and cell phenotypes.

    PubMed

    Chen, Wei-Chiang; Wu, Pei-Hsun; Phillip, Jude M; Khatau, Shyam B; Choi, Jae Min; Dallas, Matthew R; Konstantopoulos, Konstantinos; Sun, Sean X; Lee, Jerry S H; Hodzic, Didier; Wirtz, Denis

    2013-03-01

    Cell cycle distribution of adherent cells is typically assessed using flow cytometry, which precludes the measurements of many cell properties and their cycle phase in the same environment. Here we develop and validate a microscopy system to quantitatively analyze the cell-cycle phase of thousands of adherent cells and their associated cell properties simultaneously. This assay demonstrates that population-averaged cell phenotypes can be written as a linear combination of cell-cycle fractions and phase-dependent phenotypes. By perturbing the cell cycle through inhibition of cell-cycle regulators or changing nuclear morphology by depletion of structural proteins, our results reveal that cell cycle regulators and structural proteins can significantly interfere with each other's prima facie functions. This study introduces a high-throughput method to simultaneously measure the cell cycle and phenotypes at single-cell resolution, which reveals a complex functional interplay between the cell cycle and cell phenotypes. PMID:23319145

  5. 75 FR 20841 - Pesticide Products; Registration Applications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-21

    ... seed; cucurbit vegetables (crop group 9; excluding cantaloupe, pumpkin, watermelon, winter squash); cantaloupe; pumpkin; watermelon; winter squash; edible-podded legume vegetables (subgroup 6A); field...

  6. Fragmentation of cancer cells

    NASA Astrophysics Data System (ADS)

    Vanapalli, Siva; Kamyabi, Nabiollah

    Tumor cells have to travel through blood capillaries to be able to metastasize and colonize in distant organs. Among the numerous cells that are shed by the primary tumor, very few survive in circulation. In vivo studies have shown that tumor cells can undergo breakup at microcapillary junctions affecting their survival. It is currently unclear what hydrodynamic and biomechanical factors contribute to fragmentation and moreover how different are the breakup dynamics of highly and weakly metastatic cells. In this study, we use microfluidics to investigate flow-induced breakup of prostate and breast cancer cells. We observe several different modes of breakup of cancer cells, which have striking similarities with breakup of viscous drops. We quantify the breakup time and find that highly metastatic cancer cells take longer to breakup than lowly metastatic cells suggesting that tumor cells may dynamically modify their deformability to avoid fragmentation. We also identify the role that cytoskeleton and membrane plays in the breakup process. Our study highlights the important role that tumor cell fragmentation plays in cancer metastasis. Cancer Prevention and Research Institute of Texas.

  7. T Cells in Fish

    PubMed Central

    Nakanishi, Teruyuki; Shibasaki, Yasuhiro; Matsuura, Yuta

    2015-01-01

    Cartilaginous and bony fish are the most primitive vertebrates with a thymus, and possess T cells equivalent to those in mammals. There are a number of studies in fish demonstrating that the thymus is the essential organ for development of T lymphocytes from early thymocyte progenitors to functionally competent T cells. A high number of T cells in the intestine and gills has been reported in several fish species. Involvement of CD4+ and CD8α+ T cells in allograft rejection and graft-versus-host reaction (GVHR) has been demonstrated using monoclonal antibodies. Conservation of CD4+ helper T cell functions among teleost fishes has been suggested in a number studies employing mixed leukocyte culture (MLC) and hapten/carrier effect. Alloantigen- and virus-specific cytotoxicity has also been demonstrated in ginbuna and rainbow trout. Furthermore, the important role of cell-mediated immunity rather than humoral immunity has been reported in the protection against intracellular bacterial infection. Recently, the direct antibacterial activity of CD8α+, CD4+ T-cells and sIgM+ cells in fish has been reported. In this review, we summarize the recent progress in T cell research focusing on the tissue distribution and function of fish T cells. PMID:26426066

  8. Brain tumor stem cells.

    PubMed

    Palm, Thomas; Schwamborn, Jens C

    2010-06-01

    Since the end of the 'no-new-neuron' theory, emerging evidence from multiple studies has supported the existence of stem cells in neurogenic areas of the adult brain. Along with this discovery, neural stem cells became candidate cells being at the origin of brain tumors. In fact, it has been demonstrated that molecular mechanisms controlling self-renewal and differentiation are shared between brain tumor stem cells and neural stem cells and that corruption of genes implicated in these pathways can direct tumor growth. In this regard, future anticancer approaches could be inspired by uncovering such redundancies and setting up treatments leading to exhaustion of the cancer stem cell pool. However, deleterious effects on (normal) neural stem cells should be minimized. Such therapeutic models underline the importance to study the cellular mechanisms implicated in fate decisions of neural stem cells and the oncogenic derivation of adult brain cells. In this review, we discuss the putative origins of brain tumor stem cells and their possible implications on future therapies. PMID:20370314

  9. Simple Cell Balance Circuit

    NASA Technical Reports Server (NTRS)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  10. The leukemic stem cell

    PubMed Central

    Jordan, Craig T.

    2007-01-01

    Malignant stem cells have recently been described as the source of several types of human cancer. These unique cell types are typically rare and possess properties that are distinct from most other tumor cells. The properties of leukemic stem cells indicate that current chemotherapy drugs will not be effective. The use of current cytotoxic agents is not effective in leukemia because the agents target both the leukemic and normal stem cell populations. Consequently, new strategies are required that specifically and preferentially target the malignant stem cell population, while sparing normal stem cells. Several well known agents are lethal for the leukemic stem cell in preclinical testing. They include parthenolide, commonly known as feverfew, and TDZD-8. They have undergone various levels of preclinical development, but have not been used in patients as yet in the cancer setting. These drugs and combinations of existing therapies that target the leukemic stem cell population may provide a cure in this disease. This article summarizes recent findings in the leukemic stem cell field and discusses new directions for therapy. PMID:17336250

  11. Stem Cell Separation Technologies

    PubMed Central

    Zhu, Beili; Murthy, Shashi K.

    2012-01-01

    Stem cell therapy and translational stem cell research require large-scale supply of stem cells at high purity and viability, thus leading to the development of stem cell separation technologies. This review covers key technologies being applied to stem cell separation, and also highlights exciting new approaches in this field. First, we will cover conventional separation methods that are commercially available and have been widely adapted. These methods include Fluorescence-activated cell sorting (FACS), Magnet-activated cell sorting (MACS), pre-plating, conditioned expansion media, density gradient centrifugation, field flow fractionation (FFF), and dielectrophoresis (DEP). Next, we will introduce emerging novel methods that are currently under development. These methods include improved aqueous two-phase system, systematic evolution of ligands by exponential enrichment (SELEX), and various types of microfluidic platforms. Finally, we will discuss the challenges and directions towards future breakthroughs for stem cell isolation. Advancing stem cell separation techniques will be essential for clinical and research applications of stem cells. PMID:23505616

  12. T follicular regulatory cells.

    PubMed

    Sage, Peter T; Sharpe, Arlene H

    2016-05-01

    Pathogen exposure elicits production of high-affinity antibodies stimulated by T follicular helper (Tfh) cells in the germinal center reaction. Tfh cells provide both costimulation and stimulatory cytokines to B cells to facilitate affinity maturation, class switch recombination, and plasma cell differentiation within the germinal center. Under normal circumstances, the germinal center reaction results in antibodies that precisely target foreign pathogens while limiting autoimmunity and excessive inflammation. In order to have this degree of control, the immune system ensures Tfh-mediated B-cell help is regulated locally in the germinal center. The recently identified T follicular regulatory (Tfr) cell subset can migrate to the germinal center and inhibit Tfh-mediated B-cell activation and antibody production. Although many aspects of Tfr cell biology are still unclear, recent data have begun to delineate the specialized roles of Tfr cells in controlling the germinal center reaction. Here we discuss the current understanding of Tfr-cell differentiation and function and how this knowledge is providing new insights into the dynamic regulation of germinal centers, and suggesting more efficacious vaccine strategies and ways to treat antibody-mediated diseases. PMID:27088919

  13. Epithelial Cell Adhesion Molecule

    PubMed Central

    Trzpis, Monika; McLaughlin, Pamela M.J.; de Leij, Lou M.F.H.; Harmsen, Martin C.

    2007-01-01

    The epithelial cell adhesion molecule (EpCAM, CD326) is a glycoprotein of ∼40 kd that was originally identified as a marker for carcinoma, attributable to its high expression on rapidly proliferating tumors of epithelial origin. Normal epithelia express EpCAM at a variable but generally lower level than carcinoma cells. In early studies, EpCAM was proposed to be a cell-cell adhesion molecule. However, recent insights revealed a more versatile role for EpCAM that is not limited only to cell adhesion but includes diverse processes such as signaling, cell migration, proliferation, and differentiation. Cell surface expression of EpCAM may actually prevent cell-cell adhesion. Here, we provide a comprehensive review of the current knowledge on EpCAM biology in relation to other cell adhesion molecules. We discuss the implications of the newly identified functions of EpCAM in view of its prognostic relevance in carcinoma, inflammatory pathophysiology, and tissue development and regeneration as well as its role in normal epithelial homeostasis. PMID:17600130

  14. Single cell wound repair

    PubMed Central

    Abreu-Blanco, Maria Teresa; Verboon, Jeffrey M

    2011-01-01

    Cell wounding is a common event in the life of many cell types, and the capacity of the cell to repair day-to-day wear-and-tear injuries, as well as traumatic ones, is fundamental for maintaining tissue integrity. Cell wounding is most frequent in tissues exposed to high levels of stress. Survival of such plasma membrane disruptions requires rapid resealing to prevent the loss of cytosolic components, to block Ca2+ influx and to avoid cell death. In addition to patching the torn membrane, plasma membrane and cortical cytoskeleton remodeling are required to restore cell function. Although a general understanding of the cell wound repair process is in place, the underlying mechanisms of each step of this response are not yet known. We have developed a model to study single cell wound repair using the early Drosophila embryo. Our system combines genetics and live imaging tools, allowing us to dissect in vivo the dynamics of the single cell wound response. We have shown that cell wound repair in Drosophila requires the coordinated activities of plasma membrane and cytoskeleton components. Furthermore, we identified an unexpected role for E-cadherin as a link between the contractile actomyosin ring and the newly formed plasma membrane plug. PMID:21922041

  15. Mast Cell Function

    PubMed Central

    da Silva, Elaine Zayas Marcelino; Jamur, Maria Célia

    2014-01-01

    Since first described by Paul Ehrlich in 1878, mast cells have been mostly viewed as effectors of allergy. It has been only in the past two decades that mast cells have gained recognition for their involvement in other physiological and pathological processes. Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment. Mast cell maturation, phenotype and function are a direct consequence of the local microenvironment and have a marked influence on their ability to specifically recognize and respond to various stimuli through the release of an array of biologically active mediators. These features enable mast cells to act as both first responders in harmful situations as well as to respond to changes in their environment by communicating with a variety of other cells implicated in physiological and immunological responses. Therefore, the critical role of mast cells in both innate and adaptive immunity, including immune tolerance, has gained increased prominence. Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases. This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role. PMID:25062998

  16. Cell to substratum and cell to cell interactions of microalgae.

    PubMed

    Ozkan, Altan; Berberoglu, Halil

    2013-12-01

    This paper reports the cell to substratum and cell to cell interactions of a diverse group of microalgae based on the Extended Derjaguin, Landau, Verwey, Overbeek (XDLVO) approach using the previously reported physico-chemical surface properties. The microalgae included 10 different species of green algae and diatoms from both freshwater and saltwater environments while the substrata included glass, indium-tin oxide (ITO), stainless steel, polycarbonate, polyethylene, and polystryrene. The results indicated that acid-base interactions were the dominating mechanism of interaction for microalgae. For green algae, if at least one of the interacting surfaces was hydrophobic, adhesion at primary minimum was predicted without any energy barrier. However, most diatom systems featured energy barriers for adhesion due to repulsive van der Waals interactions. The results reported in this study are expected to provide useful data and insight into the interaction mechanisms of microalgae cells with each other and with substrata for a number of practical applications including prevention of biofouling of photobioreactors and other man-made surfaces, promotion of biofilm formation in algal biofilm photobioreactors, and developing bioflocculation strategies for energy efficient harvesting of algal biomass. Particularly, Botryococcus braunii and Cerithiopsis fusiformis were identified as promising species for biofloccuation and biofilm formation in freshwater and saltwater aquatic systems, respectively. Finally, based on the observed trends in this study, use of hydrophilic algae and hydrophilic coatings over surfaces are recommended for minimizing biofouling in aquatic systems. PMID:24004676

  17. Lung Cell Oxidant Injury

    PubMed Central

    Suttorp, Norbert; Simon, Lawrence M.

    1982-01-01

    The oxidant damage of lung tissue during in vivo hyperoxic exposure appears to be amplified by neutrophils that release toxic amounts of oxygen metabolites. In our studies cloned lung epithelial cells (L2 cells), lung fibroblasts, and pulmonary artery endothelial cells were cultured under either ambient (Po2 ∼ 140 torr) or hyperoxic (Po2 ∼ 630 torr) conditions for 48 h (24 h for endothelial cells). After cultivation, phorbol myristate acetate- or opsonized zymosan-stimulated neutrophils were added to the cultivated monolayers for 4 h, and lung cell damage was quantitated using 51Cr release as an index. The data show that stimulated neutrophils are able to injure the three lung cell lines tested, with endothelial cells being highly susceptible to this injury and L2 cells being slightly more susceptible than lung fibroblasts. The studies also demonstrate that all three lung cell lines exposed to sustained hyperoxia are more susceptible to neutrophil-mediated cytotoxicity than their time-matched air controls. Hydrogen peroxide was the main toxic oxygen metabolite because catalase (2,500 U/ml) completely protected the target cells. Equivalent quantities of hydrogen peroxide generated by glucose oxidase instead of by neutrophils gave a similar degree of target cell injury. Superoxide dismutase at high concentrations (250 μg/ml) provided some protection. Other systems that detoxify oxygen metabolites were without protective effect. These findings indicate that the increase in susceptibility of lung cells to neutrophil-mediated oxidant damage is a toxic effect of hyperoxia on lung cells. This specific manifestation of oxygen damage provides insight into the integration between primary mechanisms (oxygen exposure) and secondary mechanisms (release of oxygen metabolites by neutrophils) with respect to the cellular basis for pulmonary oxygen toxicity. PMID:6284800

  18. The Chlamydomonas Cell Cycle

    PubMed Central

    Cross, Frederick R.; Umen, James G.

    2015-01-01

    The position of Chlamydomonas within the eukaryotic phylogeny makes it a unique model in at least two important ways: as a representative of the critically important, early-diverging lineage leading to plants, and as a microbe retaining important features of the last eukaryotic common ancestor (LECA) that have been lost in the highly studied yeast lineages. Its cell biology has been studied for many decades, and it has well-developed experimental genetic tools, both classical (Mendelian) and molecular. Unlike land plants, it is a haploid with very few gene duplicates, making it ideal for loss-of-function genetic studies. The Chlamydomonas cell cycle has a striking temporal and functional separation between cell growth and rapid cell divisions, probably connected to the interplay between diurnal cycles that drive photosynthetic cell growth with the cell division cycle; it also exhibits a highly choreographed interaction between the cell cycle and its centriole/basal body/flagellar cycle. Here we review the current status of studies of the Chlamydomonas cell cycle. We begin with an overview of cell cycle control in the well-studied yeast and animal systems, which has yielded a canonical, well-supported model. We discuss briefly what is known about similarities and differences in plant cell cycle control compared to this model. We next review the cytology and cell biology of the multiple fission cell cycle of Chlamydomonas. Lastly we review recent genetic approaches and insights into Chlamydomonas cell cycle regulation that have been enabled by a new generation of genomics-based tools. PMID:25690512

  19. Successful differentiation to T cells, but unsuccessful B-cell generation, from B-cell-derived induced pluripotent stem cells.

    PubMed

    Wada, Haruka; Kojo, Satoshi; Kusama, Chie; Okamoto, Naoki; Sato, Yorino; Ishizuka, Bunpei; Seino, Ken-ichiro

    2011-01-01

    Forced expression of certain transcription factors in somatic cells results in generation of induced pluripotent stem (iPS) cells, which differentiate into various cell types. We investigated T-cell and B-cell lineage differentiation from iPS cells in vitro. To evaluate the impact of iPS cell source, murine splenic B-cell-derived iPS (B-iPS) cells were generated after retroviral transduction of four transcription factors (Oct4, Sox2, Klf4 and c-Myc). B-iPS cells were identical to embryonic stem (ES) cells and mouse embryonic fibroblast (MEF)-derived iPS cells in morphology, ES cell marker expression as well as teratoma and chimera mouse formation. Both B-iPS and MEF-derived iPS cells differentiated into lymphocytes in OP9 co-culture systems. Both efficiently differentiated into T-cell lineage that produced IFN-γ on T-cell receptor stimulation. However, iPS cells including B-iPS cells were relatively resistant to B-cell lineage differentiation. One of the reasons of the failure of B-cell lineage differentiation seemed due to a defect of Pax5 expression in the differentiated cells. Therefore, current in vitro differentiation systems using iPS cells are sufficient for inducing T-cell but not B-cell lineage. PMID:21135032

  20. Cell adhesion in regulation of asymmetric stem cell division

    PubMed Central

    Yamashita, Yukiko M.

    2010-01-01

    Adult stem cells inevitably communicate with their cellular neighbors within the tissues they sustain. Indeed, such communication, particularly with components of the stem cell niche, is essential for many aspects of stem cell behavior, including the maintenance of stem cell identity and asymmetric cell division. Cell adhesion mediates this communication by placing stem cells in close proximity to the signaling source and by providing a polarity cue that orients stem cells. Here, I review the recent discovery that cell adhesion molecules govern the behavior of stem cells. PMID:20724132

  1. New cell sources for T cell engineering and adoptive immunotherapy.

    PubMed

    Themeli, Maria; Rivière, Isabelle; Sadelain, Michel

    2015-04-01

    The promising clinical results obtained with engineered T cells, including chimeric antigen receptor (CAR) therapy, call for further advancements to facilitate and broaden their applicability. One potentially beneficial innovation is to exploit new T cell sources that reduce the need for autologous cell manufacturing and enable cell transfer across histocompatibility barriers. Here we review emerging T cell engineering approaches that utilize alternative T cell sources, which include virus-specific or T cell receptor-less allogeneic T cells, expanded lymphoid progenitors, and induced pluripotent stem cell (iPSC)-derived T lymphocytes. The latter offer the prospect for true off-the-shelf, genetically enhanced, histocompatible cell therapy products. PMID:25842976

  2. Oral Rigosertib for Squamous Cell Carcinoma

    ClinicalTrials.gov

    2016-05-18

    Head and Neck Squamous Cell Carcinoma; Anal Squamous Cell Carcinoma; Lung Squamous Cell Carcinoma; Cervical Squamous Cell Carcinoma; Esophageal Squamous Cell Carcinoma; Skin Squamous Cell Carcinoma; Penile Squamous Cell Carcinoma

  3. Cell-Substrate Adhesion by Amoeboid Cells

    NASA Astrophysics Data System (ADS)

    Flanders, Bret; Panta, Krishna

    Amoeboid migration is a rapid (10 μm min-1) mode of migration that some tumor cells exhibit. To permit such rapid movement, the adhesive contacts between the cell and the substrate must be relatively short-lived and weak. In this study, we investigate the basic adhesive character of amoeboid cells (D. discoideum) in contact with silanized glass substrates. We observe the initiation and spreading of the adhesive contacts that these cells establish as they settle under gravity onto the substrate and relax towards mechanical equilibrium. The use of interference reflection microscopy and cellular tethering measurements have allowed us to determine the basic adhesive properties of the cell: the membrane-medium interfacial energy; the bending modulus; the equilibrium contact angle; and the work of adhesion. We find the time scale on which settling occurs to be longer than expected. Implications of these results on adhesion and migration will be discussed. The authors are grateful for support from NSF (CBET-1451903) and NIH (1R21EY026392).

  4. Cell Therapy in Dermatology

    PubMed Central

    Petrof, Gabriela; Abdul-Wahab, Alya; McGrath, John A.

    2014-01-01

    Harnessing the regenerative capacity of keratinocytes and fibroblasts from human skin has created new opportunities to develop cell-based therapies for patients. Cultured cells and bioengineered skin products are being used to treat patients with inherited and acquired skin disorders associated with defective skin, and further clinical trials of new products are in progress. The capacity of extracutaneous sources of cells such as bone marrow is also being investigated for its plasticity in regenerating skin, and new strategies, such as the derivation of inducible pluripotent stem cells, also hold great promise for future cell therapies in dermatology. This article reviews some of the preclinical and clinical studies and future directions relating to cell therapy in dermatology, particularly for inherited skin diseases associated with fragile skin and poor wound healing. PMID:24890834

  5. Concentrator silicon cell research

    SciTech Connect

    Green, M.A.; Wenham, S.R.; Zhang, F.; Zhao, J.; Wang, A.

    1992-04-01

    This project continued the developments of high-efficiency silicon concentrator solar cells with the goal of achieving a cell efficiency in the 26 to 27 percent range at a concentration level of 150 suns of greater. The target efficiency was achieved with the new PERL (passivated emitter, rear locally diffused) cell structure, but only at low concentration levels around 20 suns. The PERL structure combines oxide passivation of both top and rear surfaces of the cells with small area contact to heavily doped regions on the top and rear surfaces. Efficiency in the 22 to 23 percent range was also demonstrated for large-area concentrator cells fabricated with the buried contact solar cell processing sequence, either when combined with prismatic covers or with other innovative approaches to reduce top contact shadowing. 19 refs.

  6. Aneuploidy in stem cells

    PubMed Central

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to reality. However, as somatic cells might have accumulated various chromosomal abnormalities, including aneuploidies throughout their lives, the resulting IPSCs might no longer carry the perfect blueprint for the tissue to be generated, or worse, become at risk of adopting a malignant fate. In this review, we discuss the contribution of aneuploidy to healthy tissues and how aneuploidy can lead to disease. Furthermore, we review the differences between how somatic cells and stem cells respond to aneuploidy. PMID:27354891

  7. Solar cell shingle

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G. (Inventor)

    1977-01-01

    A solar cell shingle was made of an array of solar cells on a lower portion of a substantially rectangular shingle substrate made of fiberglass cloth or the like. The solar cells may be encapsulated in flourinated ethylene propylene or some other weatherproof translucent or transparent encapsulant to form a combined electrical module and a roof shingle. The interconnected solar cells were connected to connectors at the edge of the substrate through a connection to a common electrical bus or busses. An overlap area was arranged to receive the overlap of a cooperating similar shingle so that the cell portion of the cooperating shingle may overlie the overlap area of the roof shingle. Accordingly, the same shingle serves the double function of an ordinary roof shingle which may be applied in the usual way and an array of cooperating solar cells from which electrical energy may be collected.

  8. Cell Salvage in Obstetrics.

    PubMed

    Goucher, Haley; Wong, Cynthia A; Patel, Samir K; Toledo, Paloma

    2015-08-01

    Intraoperative cell salvage is a strategy to decrease the need for allogeneic blood transfusion. Traditionally, cell salvage has been avoided in the obstetric population because of the perceived risk of amniotic fluid embolism or induction of maternal alloimmunization. With advances in cell salvage technology, the risks of cell salvage in the obstetric population parallel those in the general population. Levels of fetal squamous cells in salvaged blood are comparable to those in maternal venous blood at the time of placental separation. No definite cases of amniotic fluid embolism have been reported and appear unlikely with modern equipment. Cell salvage is cost-effective in patients with predictably high rates of transfusion, such as parturients with abnormal placentation. PMID:26197375

  9. Traction in smooth muscle cells varies with cell spreading

    NASA Technical Reports Server (NTRS)

    Tolic-Norrelykke, Iva Marija; Wang, Ning

    2005-01-01

    Changes in cell shape regulate cell growth, differentiation, and apoptosis. It has been suggested that the regulation of cell function by the cell shape is a result of the tension in the cytoskeleton and the distortion of the cell. Here we explore the association between cell-generated mechanical forces and the cell morphology. We hypothesized that the cell contractile force is associated with the degree of cell spreading, in particular with the cell length. We measured traction fields of single human airway smooth muscle cells plated on a polyacrylamide gel, in which fluorescent microbeads were embedded to serve as markers of gel deformation. The traction exerted by the cells at the cell-substrate interface was determined from the measured deformation of the gel. The traction was measured before and after treatment with the contractile agonist histamine, or the relaxing agonist isoproterenol. The relative increase in traction induced by histamine was negatively correlated with the baseline traction. On the contrary, the relative decrease in traction due to isoproterenol was independent of the baseline traction, but it was associated with cell shape: traction decreased more in elongated than in round cells. Maximum cell width, mean cell width, and projected area of the cell were the parameters most tightly coupled to both baseline and histamine-induced traction in this study. Wide and well-spread cells exerted larger traction than slim cells. These results suggest that cell contractility is controlled by cell spreading.

  10. Entosis and Related Forms of Cell Death within Cells.

    PubMed

    Wang, Y; Wang, X-D

    2015-01-01

    By eliminating the unneeded or mutant cells, programmed cell death actively participates in a wide range of biological processes from embryonic development to homeostasis maintenance in adult. Continuing efforts have identified multiple cell death pathways, with apoptosis, necrosis and autophage the mostly studied. Recently a unique cell death pathway called "cell-in-cell death" has been defined. Unlike traditional cell death pathways, cell-in-cell death, characterized by cell death within another cell, is triggered by the invasion of one cell into its neighbor and executed by either lysosome-dependent degradation or caspase-dependent apoptosis. With remarkable progresses on cell-in-cell over past few years, multiple mechanisms, including entosis, cannibalism and emperitosis, are found to be responsible for cell-in-cell death. Some key questions, such as specific biochemical markers to distinguish precisely the properties of different cell-in-cell structures and the physiological and pathological relevance, remain to be addressed. In light of this situation and a surge of interests, leading scientists in this field intend to share with readers current research progresses on cell-in-cell structures from different model systems through this special edition on cell-in-cell. The mechanistic advances will be highlighted while the future researches be speculated. PMID:26511710

  11. Quantitative methods for analyzing cell-cell adhesion in development.

    PubMed

    Kashef, Jubin; Franz, Clemens M

    2015-05-01

    During development cell-cell adhesion is not only crucial to maintain tissue morphogenesis and homeostasis, it also activates signalling pathways important for the regulation of different cellular processes including cell survival, gene expression, collective cell migration and differentiation. Importantly, gene mutations of adhesion receptors can cause developmental disorders and different diseases. Quantitative methods to measure cell adhesion are therefore necessary to understand how cells regulate cell-cell adhesion during development and how aberrations in cell-cell adhesion contribute to disease. Different in vitro adhesion assays have been developed in the past, but not all of them are suitable to study developmentally-related cell-cell adhesion processes, which usually requires working with low numbers of primary cells. In this review, we provide an overview of different in vitro techniques to study cell-cell adhesion during development, including a semi-quantitative cell flipping assay, and quantitative single-cell methods based on atomic force microscopy (AFM)-based single-cell force spectroscopy (SCFS) or dual micropipette aspiration (DPA). Furthermore, we review applications of Förster resonance energy transfer (FRET)-based molecular tension sensors to visualize intracellular mechanical forces acting on cell adhesion sites. Finally, we describe a recently introduced method to quantitate cell-generated forces directly in living tissues based on the deformation of oil microdroplets functionalized with adhesion receptor ligands. Together, these techniques provide a comprehensive toolbox to characterize different cell-cell adhesion phenomena during development. PMID:25448695

  12. Improving Cell Engraftment in Cardiac Stem Cell Therapy

    PubMed Central

    Xie, Xiaoyun

    2016-01-01

    Myocardial infarction (MI) affects millions of people worldwide. MI causes massive cardiac cell death and heart function decrease. However, heart tissue cannot effectively regenerate by itself. While stem cell therapy has been considered an effective approach for regeneration, the efficacy of cardiac stem cell therapy remains low due to inferior cell engraftment in the infarcted region. This is mainly a result of low cell retention in the tissue and poor cell survival under ischemic, immune rejection and inflammatory conditions. Various approaches have been explored to improve cell engraftment: increase of cell retention using biomaterials as cell carriers; augmentation of cell survival under ischemic conditions by preconditioning cells, genetic modification of cells, and controlled release of growth factors and oxygen; and enhancement of cell survival by protecting cells from excessive inflammation and immune surveillance. In this paper, we review current progress, advantages, disadvantages, and potential solutions of these approaches. PMID:26783405

  13. Characterization of Amniotic Stem Cells

    PubMed Central

    Koike, Chika; Zhou, Kaixuan; Takeda, Yuji; Fathy, Moustafa; Okabe, Motonori; Yoshida, Toshiko; Nakamura, Yukio; Kato, Yukio

    2014-01-01

    Abstract The amnion membrane is developed from embryo-derived cells, and amniotic cells have been shown to exhibit multidifferentiation potential. These cells represent a desirable source for stem cells for a variety of reasons. However, to date very few molecular analyses of amnion-derived cells have been reported, and efficient markers for isolating the stem cells remain unclear. This paper assesses the characterization of amnion-derived cells as stem cells by examining stemness marker expressions for amnion-derived epithelial cells and mesenchymal cells by flow cytometry, immunocytochemistry, and quantitative PCR. Flow cytometry revealed that amnion epithelial cells expressed CD133, CD 271, and TRA-1-60, whereas mecenchymal cells expressed CD44, CD73, CD90, and CD105. Immunohistochemistry showed that both cells expressed the stemness markers Oct3/4, Sox2, Klf4, and SSEA4. Stemness genes' expression in amnion epithelial cells, mesenchymal cells, fibroblast, bone marrow–derived mesenchymal stem cells (MSCs), and induced pluripotent stem cells (iPSCs) was compared by quantitative reverse-transcription polymerase chain reaction (RT-PCR). Amnion-derived epithelial cells and mesenchymal cells expressed Oct3/4, Nanog, and Klf4 more than bone marrow–derived MSCs. The sorted TRA1-60–positive cells expressed Oct3/4, Nanog, and Klf4 more than unsorted cells or TRA1-60–negative cells. TRA1-60 can be a marker for isolating amnion epithelial stem cells. PMID:25068631

  14. Paratesticular Spindle Cell Rhabdomyosarcoma

    PubMed Central

    Dey, Biswajit; Bharti, Jyotsna Naresh; Dange, Prasad; Desai, Parth Anil; Khurana, Nita; Chander, Jagdish

    2015-01-01

    Spindle cell rhabdomyosarcoma is a rare variant of embryonal rhabdomyosarcoma that affects young males and most commonly involves the paratesticular region. We report a case of paratesticular spindle cell rhabdomyosarcoma in a 14-year-old boy, who presented with a painless scrotal mass. Left inguinal orchidectomy was performed. Histopathological and immunohistochemical examination of the mass revealed spindle cell rhabdomyosarcoma of the paratesticular region. PMID:26500726

  15. Rechargeable Magnesium Power Cells

    NASA Technical Reports Server (NTRS)

    Koch, Victor R.; Nanjundiah, Chenniah; Orsini, Michael

    1995-01-01

    Rechargeable power cells based on magnesium anodes developed as safer alternatives to high-energy-density cells like those based on lithium and sodium anodes. At cost of some reduction in energy density, magnesium-based cells safer because less susceptible to catastrophic meltdown followed by flames and venting of toxic fumes. Other advantages include ease of handling, machining, and disposal, and relatively low cost.

  16. Heterojunction solar cell

    DOEpatents

    Olson, Jerry M.

    1994-01-01

    A high-efficiency single heterojunction solar cell wherein a thin emitter layer (preferably Ga.sub.0.52 In.sub.0.48 P) forms a heterojunction with a GaAs absorber layer. The conversion effiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the emitter layer.

  17. Heterojunction solar cell

    DOEpatents

    Olson, J.M.

    1994-08-30

    A high-efficiency single heterojunction solar cell is described wherein a thin emitter layer (preferably Ga[sub 0.52]In[sub 0.48]P) forms a heterojunction with a GaAs absorber layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the emitter layer. 1 fig.

  18. Systems cell biology

    PubMed Central

    Mast, Fred D.; Ratushny, Alexander V.

    2014-01-01

    Systems cell biology melds high-throughput experimentation with quantitative analysis and modeling to understand many critical processes that contribute to cellular organization and dynamics. Recently, there have been several advances in technology and in the application of modeling approaches that enable the exploration of the dynamic properties of cells. Merging technology and computation offers an opportunity to objectively address unsolved cellular mechanisms, and has revealed emergent properties and helped to gain a more comprehensive and fundamental understanding of cell biology. PMID:25225336

  19. Dental stem cell patents.

    PubMed

    Morsczeck, Christian; Frerich, Bernhard; Driemel, Oliver

    2009-01-01

    A complex human tissue harbors stem cells that are responsible for its maintenance or repair. These stem cells have been isolated also from dental tissues such as the periodontal ligament, dental papilla or dental follicle and they may offer novel applications in dentistry. This following review summarizes patents about dental stem cells for dental tissue engineering and considers their value for regenerative dentistry. PMID:19149737

  20. CARTILAGE CELL CLUSTERS

    PubMed Central

    Lotz, Martin K.; Otsuki, Shuhei; Grogan, Shawn P.; Sah, Robert; Terkeltaub, Robert; D’Lima, Darryl

    2010-01-01

    The formation of new cell clusters is a histological hallmark of arthritic cartilage but the biology of clusters and their role in disease are poorly understood. This is the first comprehensive review of clinical and experimental conditions associated with cluster formation. Genes and proteins that are expressed in cluster cells, the cellular origin of the clusters, mechanisms that lead to cluster formation and the role of cluster cells in pathogenesis are discussed. PMID:20506158

  1. Solar cell encapsulation

    NASA Technical Reports Server (NTRS)

    Gupta, Amitava (Inventor); Ingham, John D. (Inventor); Yavrouian, Andre H. (Inventor)

    1983-01-01

    A polymer syrup for encapsulating solar cell assemblies. The syrup includes uncrosslinked poly(n-butyl)acrylate dissolved in n-butyl acrylate monomer. Preparation of the poly(n-butyl)acrylate and preparation of the polymer syrup is disclosed. Methods for applying the polymer syrup to solar cell assemblies as an encapsulating pottant are described. Also included is a method for solar cell construction utilizing the polymer syrup as a dual purpose adhesive and encapsulating material.

  2. Mechanics of the Cell

    NASA Astrophysics Data System (ADS)

    Boal, David

    2012-01-01

    Preface; List of symbols; 1. Introduction to the cell; 2. Soft materials and fluids; Part I. Rods and Ropes: 3. Polymers; 4. Complex filaments; 5. Two-dimensional networks; 6. Three-dimensional networks; Part II. Membranes: 7. Biomembranes; 8. Membrane undulations; 9. Intermembrane and electrostatic forces; Part III. The Whole Cell: 10. Structure of the simplest cells; 11. Dynamic filaments; 12. Growth and division; 13. Signals and switches; Appendixes; Glossary; References; Index.

  3. Direct hydrocarbon fuel cells

    DOEpatents

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  4. Stretching Cells with Light

    NASA Astrophysics Data System (ADS)

    Guck, Jochen

    2003-03-01

    Trapped in a two-beam laser trap, any dielectric object experiences surface stresses induced by the laser light that lead to a "stretching" of the object. This can be explained with simple ray optics as well as with a modified Mie theory approach. Based on this phenomenon we have developed an optical tool to probe the viscoelastic properties of individual cells - an optical stretcher. The cell's deformation at a known induced stress reveals the mechanical properties of the cell and the underlying cytoskeleton. Thus, the optical stretcher can be used for contact-free microrheology on individual cells. Step-stress experiments on mouse fibroblasts reveal two main time regimes. At stress duration times shorter than a minute cells behave like a passive viscoelastic fluid. The frequency dependence of the complex shear modulus and the terminal relaxation time are consistent with a weakly entangled, transiently crosslinked actin gel, while contributions from other cytoskeletal filaments can be largely ruled out. At stretching times longer than a minute cells show an active response evidenced by a continued elongation after stretch. Malignantly transformed fibroblasts are less elastic and less viscous. Experiments on various other cell types with the optical stretcher confirm very generally that the viscoelastic response of cells changes during the progression of cancer and other diseases, which are accompanied by cytoskeletal changes, and the normal differentiation of cells. This suggests using optical deformability as a novel inherent cell marker. Instead of having to "look" for changes, light can now directly be used to "feel" for altered cells. Incorporated into a microfluidic device this can be done at rates that could eventually rival flow cytometers rendering the optical stretcher an ideal device for cytological diagnosis of disease and the screening and sorting of heterogeneous cell populations.

  5. Cell-in-cell structures are involved in the competition between cells in human tumors.

    PubMed

    Sun, Qiang; Huang, Hongyan; Overholtzer, Michael

    2015-01-01

    The engulfment of live cells may represent a mechanism of cell death. We reported that E-cadherin (epithelial cadherin) expression in human cancer cells favors the formation of cell-in-cell structures through the mechanism known as entosis, and that entosis contributes to a form of cellular competition in heterogeneous cancer cell populations. PMID:27308493

  6. Cell-in-cell structures are involved in the competition between cells in human tumors

    PubMed Central

    Sun, Qiang; Huang, Hongyan; Overholtzer, Michael

    2015-01-01

    The engulfment of live cells may represent a mechanism of cell death. We reported that E-cadherin (epithelial cadherin) expression in human cancer cells favors the formation of cell-in-cell structures through the mechanism known as entosis, and that entosis contributes to a form of cellular competition in heterogeneous cancer cell populations. PMID:27308493

  7. The quantified cell.

    PubMed

    Flamholz, Avi; Phillips, Rob; Milo, Ron

    2014-11-01

    The microscopic world of a cell can be as alien to our human-centered intuition as the confinement of quarks within protons or the event horizon of a black hole. We are prone to thinking by analogy-Golgi cisternae stack like pancakes, red blood cells look like donuts-but very little in our human experience is truly comparable to the immensely crowded, membrane-subdivided interior of a eukaryotic cell or the intricately layered structures of a mammalian tissue. So in our daily efforts to understand how cells work, we are faced with a challenge: how do we develop intuition that works at the microscopic scale? PMID:25368429

  8. Plant cell membranes

    SciTech Connect

    Packer, L.; Douce, R.

    1987-01-01

    The contents of this book are: Cells, Protoplasts, Vacuoles and Liposomes; Tonoplasts; Nuclei, Endolplasmic Reticulum, and Plasma Membrane; Peroxisomes; Plastids; Teneral Physical and Biochemical Methods; and Mitochondira.

  9. Fuel cell technology program

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A fuel cell technology program was established to advance the state-of-the-art of hydrogen-oxygen fuel cells using low temperature, potassium hydroxide electrolyte technology as the base. Program tasks are described consisting of baseline cell design and stack testing, hydrogen pump design and testing, and DM-2 powerplant testing and technology extension efforts. A baseline cell configuration capable of a minimum of 2000 hours of life was defined. A 6-cell prototype stack, incorporating most of the scheme cell features, was tested for a total of 10,497 hours. A 6-cell stack incorporating all of the design features was tested. The DM-2 powerplant with a 34 cell stack, an accessory section packaged in the basic configuration anticipated for the space shuttle powerplant and a powerplant control unit, was defined, assembled, and tested. Cells were used in the stack and a drag-type hydrogen pump was installed in the accessory section. A test program was established, in conjunction with NASA/JSC, based on space shuttle orbiter mission. A 2000-hour minimum endurance test and a 5000-hour goal were set and the test started on August 8, 1972. The 2000-hour milestone was completed on November 3, 1972. On 13 March 1973, at the end of the thirty-first simulated seven-day mission and 5072 load hours, the test was concluded, all goals having been met. At this time, the DM-2 was in excellent condition and capable of additional endurance.

  10. Mesenchymal stem cells.

    PubMed

    Ding, Dah-Ching; Shyu, Woei-Cherng; Lin, Shinn-Zong

    2011-01-01

    Stem cells have two features: the ability to differentiate along different lineages and the ability of self-renewal. Two major types of stem cells have been described, namely, embryonic stem cells and adult stem cells. Embryonic stem cells (ESC) are obtained from the inner cell mass of the blastocyst and are associated with tumorigenesis, and the use of human ESCs involves ethical and legal considerations. The use of adult mesenchymal stem cells is less problematic with regard to these issues. Mesenchymal stem cells (MSCs) are stromal cells that have the ability to self-renew and also exhibit multilineage differentiation. MSCs can be isolated from a variety of tissues, such as umbilical cord, endometrial polyps, menses blood, bone marrow, adipose tissue, etc. This is because the ease of harvest and quantity obtained make these sources most practical for experimental and possible clinical applications. Recently, MSCs have been found in new sources, such as menstrual blood and endometrium. There are likely more sources of MSCs waiting to be discovered, and MSCs may be a good candidate for future experimental or clinical applications. One of the major challenges is to elucidate the mechanisms of differentiation, mobilization, and homing of MSCs, which are highly complex. The multipotent properties of MSCs make them an attractive choice for possible development of clinical applications. Future studies should explore the role of MSCs in differentiation, transplantation, and immune response in various diseases. PMID:21396235

  11. Vascular Precursor Cells

    PubMed Central

    Chaudhury, Hera; Goldie, Lauren C.

    2011-01-01

    Understanding the mechanisms that regulate the proliferation and differentiation of human stem and progenitor cells is critically important for the development and optimization of regenerative medicine strategies. For vascular regeneration studies, specifically, a true “vascular stem cell” population has not yet been identified. However, a number of cell types that exist endogenously, or can be generated or propagated ex vivo, function as vascular precursor cells and can participate in and/or promote vascular regeneration. Herein, we provide an overview of what is known about the regulation of their differentiation specifically toward a vascular endothelial cell phenotype. PMID:22866199

  12. Micro fuel cell

    SciTech Connect

    Zook, L.A.; Vanderborgh, N.E.; Hockaday, R.

    1998-12-31

    An ambient temperature, liquid feed, direct methanol fuel cell device is under development. A metal barrier layer was used to block methanol crossover from the anode to the cathode side while still allowing for the transport of protons from the anode to the cathode. A direct methanol fuel cell (DMFC) is an electrochemical engine that converts chemical energy into clean electrical power by the direct oxidation of methanol at the fuel cell anode. This direct use of a liquid fuel eliminates the need for a reformer to convert the fuel to hydrogen before it is fed into the fuel cell.

  13. Molten salt lithium cells

    DOEpatents

    Raistrick, Ian D.; Poris, Jaime; Huggins, Robert A.

    1983-01-01

    Lithium-based cells are promising for applications such as electric vehicles and load-leveling for power plants since lithium is very electropositive and light weight. One type of lithium-based cell utilizes a molten salt electrolyte and is operated in the temperature range of about 400.degree.-500.degree. C. Such high temperature operation accelerates corrosion problems and a substantial amount of energy is lost through heat transfer. The present invention provides an electrochemical cell (10) which may be operated at temperatures between about 100.degree.-170.degree. C. Cell (10) comprises an electrolyte (16), which preferably includes lithium nitrate, and a lithium or lithium alloy electrode (12).

  14. Molten salt lithium cells

    DOEpatents

    Raistrick, I.D.; Poris, J.; Huggins, R.A.

    1980-07-18

    Lithium-based cells are promising for applications such as electric vehicles and load-leveling for power plants since lithium is very electropositive and light weight. One type of lithium-based cell utilizes a molten salt electrolyte and is operated in the temperature range of about 400 to 500/sup 0/C. Such high temperature operation accelerates corrosion problems and a substantial amount of energy is lost through heat transfer. The present invention provides an electrochemical cell which may be operated at temperatures between about 100 to 170/sup 0/C. The cell is comprised of an electrolyte, which preferably includes lithium nitrate, and a lithium or lithium alloy electrode.

  15. Molten salt lithium cells

    DOEpatents

    Raistrick, Ian D.; Poris, Jaime; Huggins, Robert A.

    1982-02-09

    Lithium-based cells are promising for applications such as electric vehicles and load-leveling for power plants since lithium is very electropositive and light weight. One type of lithium-based cell utilizes a molten salt electrolyte and is operated in the temperature range of about 400.degree.-500.degree. C. Such high temperature operation accelerates corrosion problems and a substantial amount of energy is lost through heat transfer. The present invention provides an electrochemical cell (10) which may be operated at temperatures between about 100.degree.-170.degree. C. Cell (10) comprises an electrolyte (16), which preferably includes lithium nitrate, and a lithium or lithium alloy electrode (12).

  16. Microencapsulation Of Living Cells

    NASA Technical Reports Server (NTRS)

    Chang, Manchium; Kendall, James M.; Wang, Taylor G.

    1989-01-01

    In experimental technique, living cells and other biological materials encapsulated within submillimeter-diameter liquid-filled spheres. Sphere material biocompatible, tough, and compliant. Semipermeable, permitting relatively small molecules to move into and out of sphere core but preventing passage of large molecules. New technique promises to make such spherical capsules at high rates and in uniform, controllable sizes. Capsules injected into patient through ordinary hypodermic needle. Promising application for technique in treatment of diabetes. Also used to encapsulate pituitary cells and thyroid hormone adrenocortical cells for treatment of other hormonal disorders, to encapsulate other secreting cells for transplantation, and to package variety of pharmaceutical products and agricultural chemicals for controlled release.

  17. Solar cell radiation handbook

    NASA Technical Reports Server (NTRS)

    Tada, H. Y.; Carter, J. R., Jr.

    1977-01-01

    Solar cell theory cells are manufactured, and how they are modeled mathematically is reviewed. The interaction of energetic charged particle radiation with solar cells is discussed in detail and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Finally, an extensive body of data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence is presented.

  18. Nanocrystal Solar Cells

    SciTech Connect

    Gur, Ilan

    2006-12-15

    This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

  19. "Pelled-film" solar cells

    NASA Technical Reports Server (NTRS)

    Stirn, R. J.

    1980-01-01

    Cells are lighter and less expensive than conventional cells. GaAs cells are deposited on GaAs substrate coated with thin etchable layer that allows completed cell film to be peeled away from substrate. At estimated conversion of 18 percent, array of cells delivers about 1 kW of electricity per kilogram of cell material. Blanket of cells delivers energy at power-to-weight ratio about 4 times that of conventional 2-mil (0.5-mm) silicon solar cells. GaAs solar cells have better radiation resistance than silicon cells.

  20. Liver epithelial cells inhibit proliferation and invasiveness of hepatoma cells.

    PubMed

    Jeng, Kuo-Shyang; Jeng, Chi-Juei; Jeng, Wen-Juei; Sheen, I-Shyan; Li, Shih-Yun; Hung, Zih-Hang; Hsiau, Hsin-I; Yu, Ming-Che; Chang, Chiung-Fang

    2016-03-01

    Hepatocellular carcinoma (HCC) is a worldwide malignancy with poor prognosis. Liver progenitors or stem cells could be a potential therapy for HCC treatment since they migrate toward tumors. Rat liver epithelial (RLE) cells have both progenitor and stem cell-like properties. Therefore, our study elucidated the therapeutic effect of RLE cells in rat hepatoma cells. RLE cells were isolated from 10-day old rats and characterized for stem cell marker expression. RLE cells and rat hepatoma cells (H4-IIE-C3 cells) were co-cultured and divided into four groups with different ratios of RLE and hepatoma cells. Group A had only rat hepatoma cells as a control group. The ratios of rat hepatoma and RLE cells in group B, C and D were 5:1, 1:1 and 1:5, respectively. Effective inhibition of cell proliferation and migration was found in group D when compared to group A. There was a significant decrease in Bcl2 expression and increase in late apoptosis of rat hepatoma cells when adding more RLE cells. RLE cells reduced cell proliferation and migration of rat hepatoma cells. These results suggested that RLE cells could be used as a potential cell therapy. PMID:26647726