Science.gov

Sample records for cells utilizing immunocytochemistry

  1. Digital microfluidic immunocytochemistry in single cells.

    PubMed

    Ng, Alphonsus H C; Dean Chamberlain, M; Situ, Haozhong; Lee, Victor; Wheeler, Aaron R

    2015-01-01

    We report a new technique called Digital microfluidic Immunocytochemistry in Single Cells (DISC). DISC automates protocols for cell culture, stimulation and immunocytochemistry, enabling the interrogation of protein phosphorylation on pulsing with stimulus for as little as 3 s. DISC was used to probe the phosphorylation states of platelet-derived growth factor receptor (PDGFR) and the downstream signalling protein, Akt, to evaluate concentration- and time-dependent effects of stimulation. The high time resolution of the technique allowed for surprising new observations-for example, a 10 s pulse stimulus of a low concentration of PDGF is sufficient to cause >30% of adherent fibroblasts to commit to Akt activation. With the ability to quantitatively probe signalling events with high time resolution at the single-cell level, we propose that DISC may be an important new technique for a wide range of applications, especially for screening signalling responses of a heterogeneous cell population. PMID:26104298

  2. Utility of immunocytochemistry in diagnosing leptomeningeal metastases from an intrahepatic cholangiocarcinoma.

    PubMed

    Chaudhary, Shweta; Klein, Melissa; Mehrotra, Bhoomi; Morgenstern, Nora J

    2014-01-01

    Isolated spinal leptomeningeal metastases (LMM) without brain metastases are infrequent, accounting for about 1% of all solid tumors. In LMM, cerebrospinal fluid (CSF) analyses are mostly abnormal. Demonstrations of intrathecal tumor markers are highly suggestive, but only a positive cytology is diagnostic. The initial CSF cytology can give a false negative result in up to 40-50% of patients with pathologically proven LMM on autopsy. We report a case of intrahepatic cholangiocarcinoma with spinal LMM confirmed using cytokeratin7 and pancytokeratin (AE1/AE3) immunocytochemical studies on paucicellular cerebrospinal fluid cytospin preparation. Given the paucicellularity of the smears and difficult morphologic categorization, immunocytochemistry is vital for confirmatory diagnosis and can help reduce false negative results. To the best of our knowledge this is the first case report of cytologically confirmed LMM from an intrahepatic cholangiocarcinoma while the patient was undergoing treatment. PMID:23341095

  3. Phenobarbital-induced hepatocellular proliferation: anti-bromodeoxyuridine and anti-proliferating cell nuclear antigen immunocytochemistry.

    PubMed

    Jones, H B; Clarke, N A; Barrass, N C

    1993-01-01

    We report modifications to immunocytochemical detection procedures for proliferating cell nuclear antigen (PCNA) which permit its identification in liver samples previously fixed for BrdU immunocytochemistry. Both methods have been used for the assessment of phenobarbital-induced cell proliferation in rat liver. The difficulties associated with the hitherto unsuccessful application of PCNA immunocytochemical methods to tissues fixed in formalin for BrdU visualization were overcome by epitope unmasking with acid hydrolysis, extension of primary antiserum (PC10) incubation, and employment of streptavidin-ABC-HRP. BrdU delivery via osmotic minipumps for 48 hr before euthanasia, followed by fixation in cold formalin for 14 days, yielded reliable and reproducible hepatocellular labeling and a peak of cell proliferation in all lobes on Day 3 (i.e., labeling during Days 1-3) of dosing with 80 mg/kg/day phenobarbital. Labeling indices (LI) of both control and phenobarbital-treated liver were lower in the left and right median lobes as compared with the lateral lobes. In sections of the left lateral lobe from the same liver, PCNA immunocytochemistry revealed a peak of proliferative activity (about one third of the maximum LI generated by BrdU incorporation) on Day 1. These findings, together with the advantages and disadvantages of both techniques, are discussed in the context of their applications to different investigative requirements. PMID:8093255

  4. Covalent affinity labeling, radioautography, and immunocytochemistry localize the glucocorticoid receptor in rat testicular Leydig cells

    SciTech Connect

    Stalker, A.; Hermo, L.; Antakly, T. )

    1989-12-01

    The presence and distribution of glucocorticoid receptors in the rat testis were examined by using 2 approaches: in vivo quantitative radioautography and immunocytochemistry. Radioautographic localization was made possible through the availability of a glucocorticoid receptor affinity label, dexamethasone 21-mesylate, which binds covalently to the glucocorticoid receptor, thereby preventing dissociation of the steroid-receptor complex. Adrenalectomized adult rats were injected with a tritiated (3H) form of this steroid into the testis and the tissue was processed for light-microscope radioautography. Silver grains were observed primarily over the Leydig cells of the interstitial space and to a lesser extent, over the cellular layers which make up the seminiferous epithelium, with no one cell type showing preferential labeling. To determine the specificity of the labeling, a 25- or 50-fold excess of unlabeled dexamethasone was injected simultaneously with the same dose of (3H)-dexamethasone 21-mesylate. In these control experiments, a marked reduction in label intensity was noted over the Leydig as well as tubular cells. Endocytic macrophages of the interstitium were non-specifically labeled, indicating uptake of the ligand possibly by fluid-phase endocytosis. A quantitative analysis of the label confirmed the presence of statistically significant numbers of specific binding sites for glucocorticoids in both Leydig cells and the cellular layers of the seminiferous epithelium; 86% of the label was found over Leydig cells, and only 14% over the cells of the seminiferous epithelium. These binding data were confirmed by light-microscope immunocytochemistry using a monoclonal antibody to the glucocorticoid receptor.

  5. Peritoneal fluid immunocytochemistry used for the diagnosis of a possible case of equine gastrointestinal B-cell lymphoma.

    PubMed

    Duran, Maria Carolina; Starrak, Gregory; Dickinson, Ryan; Montgomery, Julia

    2016-06-01

    After physical examination, ultrasonographic evaluation of thorax and abdomen, and peritoneal fluid analysis, gastrointestinal neoplasia with suspected diffuse peritoneal metastasis was diagnosed in a 17-year-old Arabian gelding. The owner elected euthanasia and declined postmortem examination. Immunocytochemistry analysis of the peritoneal fluid resulted in a diagnosis of B-cell lymphoma. PMID:27247458

  6. Immunophenotypic, immunocytochemistry, ultrastructural, and cytogenetic characterization of mesenchymal stem cells from equine bone marrow.

    PubMed

    Maia, Leandro; Landim-Alvarenga, Fernanda C; Da Mota, Ligia S L Silveira; De Assis Golim, Marjorie; Laufer-Amorim, Reneé; De Vita, Bruna; Barberini, Danielle Jaqueta; Listoni, Amanda Jeronimo; De Moraes, Carolina Nogueira; Heckler, Marta Cristina Thomas; Amorim, Rogério Martins

    2013-06-01

    The aim of this study was to isolate, culture, and characterize mesenchymal stem cells (MSCs) from horse bone marrow (BM) using the techniques of flow cytometry, immunocytochemistry, cytogenetics, and electron microscopy. Immunophenotypic analysis revealed the presence of MSCs with high expression of the CD90 marker, lower expression of the CD44 marker, and absent expression of the CD34 marker. In assays of differentiation, the positive response to osteogenic (OST), chondrogenic (CDG), and adipogenic (ADP) differentiation signals was observed and characterized by deposition of calcium-rich extracellular matrix (OST), proteoglycans and collagen II (CDG) and intracellular deposition of fat drops (ADP). In immunocytochemical characterization, MSCs were immunopositive for CD44, vimentin, and PCNA, and they were negative for CD13. In the ultrastructural analysis of MSCs, the most outstanding characteristic was the presence of rough endoplasmic reticulum with very dilated cisterns filled with a low electrodensity material. Additionally, MSCs had normal karyotypes (2n = 64) as evidenced by cytogenetic analysis, and aneuploidy in metaphase was not observed. The protocols for isolating, culturing, and characterizing equine MSCs used in this study were shown to be appropriate for the production of a cell population with a good potential for differentiation and without aneuploidy that can be used to study future cellular therapies. PMID:23533133

  7. Identification of newborn cells by BrdU labeling and immunocytochemistry in vivo.

    PubMed

    Magavi, Sanjay S; Macklis, Jeffrey D

    2008-01-01

    Bromodeoxyuridine, variously abbreviated as BrdU, BudR, and BrdUrd, is a halogenated thymidine analog that is permanently integrated into the DNA of dividing cells during DNA synthesis in S phase. BrdU can be immunocytochemically detected in vitro and in vivo, allowing the identification of cells that were dividing the period of BrdU exposure. In vivo, it has been used to identify the "birthdate" of cells during development, to examine the fate of postnatally generated cells, and to label cells before transplantation, for subsequent identification. PMID:18369768

  8. CSF cytology versus immunocytochemistry in meningeal carcinomatosis.

    PubMed Central

    Boogerd, W; Vroom, T M; van Heerde, P; Brutel de la Rivière, G; Peterse, J L; van der Sande, J J

    1988-01-01

    CSF immunocytochemistry with monoclonal antibodies was compared with conventional cytology to determine its sensitivity in detecting malignant cells in patients with meningeal carcinomatosis. One hundred and eighteen samples were investigated. Cytology was tumour positive in 83 samples and immunocytochemistry in 85. Dissimilar results between the two diagnostic methods were noted in 12 specimens, invariably occurring in samples with a low cell count and obtained from treated patients. Combined use of the two methods led to a 9% increase of sensitivity in detecting malignant cells compared with cytology alone. It is concluded that immunocytochemistry is of minor help in the problem of false-negative cytology in meningeal carcinomatosis. PMID:2832546

  9. Immunocytochemistry: its evolution and criteria for its application in the study of epon-embedded cells and tissue.

    PubMed

    Gosselin, E J; Cate, C C; Pettengill, O S; Sorenson, G D

    1986-01-01

    The word immunocytochemistry is currently used to describe a number of methods that can be employed to localize antigens within cells by means of antigen-specific antibodies. In this article we will review a number of these methods, including immunofluorescence, immunoperoxidase, avidin-biotin, and colloidal-gold techniques. The advantages and disadvantages of the various methods are discussed, special attention being focused upon immunocytochemical staining of plastic-embedded tissue. Studies on the light microscope level show that embedding tissue in plastic prior to immunoperoxidase staining not only improves visualization of antigen-specific staining but also provides an accurate and efficient means of prescreening tissue for antigen prior to immunocytochemical staining on the electron microscope level. Varying section thickness between 1 and 3 microns does not significantly influence staining, whereas the fixative used to preserve the tissue under study does. On the electron microscope level, the colloidal gold technique appears superior to immunoperoxidase staining. It is both esthetically more pleasing and highly sensitive. Of five different colloidal gold methods tested, the most sensitive is the two-step technique that employs an antigen-specific primary antibody followed by a gold-labeled secondary antibody. Throughout this article, special emphasis is placed on the use of proper controls, both on the light and electron microscope levels. Where possible, such controls should include substitution of specific antiserum with normal serum; the use of antigen-adsorbed antiserum; the use of antisera with specificities for antigens not present in the tissue being studied; the use of tissue previously shown to be stainable for the antigen; and if cultured cells are being studied, the use of a number of cell types that do not contain the antigen. PMID:2422914

  10. Liquid-based cytology and cell block immunocytochemistry in veterinary medicine: comparison with standard cytology for the evaluation of canine lymphoid samples.

    PubMed

    Fernandes, N C C A; Guerra, J M; Réssio, R A; Wasques, D G; Etlinger-Colonelli, D; Lorente, S; Nogueira, E; Dagli, M L Z

    2016-08-01

    Liquid-based Cytology (LBC) consists of immediate wet cell fixation with automated slide preparation. We applied LBC, cell block (CB) and immunocytochemistry to diagnose canine lymphoma and compare results with conventional cytology. Samples from enlarged lymph nodes of 18 dogs were collected and fixed in preservative solution for automated slide preparation (LBC), CB inclusion and immunophenotyping. Two CB techniques were tested: fixed sediment method (FSM) and agar method (AM). Anti-CD79a, anti-Pax5, anti-CD3 and anti-Ki67 were used in immunocytochemistry. LBC smears showed better nuclear and nucleolar definition, without cell superposition, but presented smaller cell size and worse cytoplasmic definition. FSM showed consistent cellular groups and were employed for immunocytochemistry, while AM CBs presented sparse groups of lymphocytes, with compromised analysis. Anti-Pax-5 allowed B-cell identification, both in reactive and neoplastic lymph nodes. Our preliminary report suggests that LBC and FSM together may be promising tools to improve lymphoma diagnosis through fine-needle aspiration. PMID:25665030

  11. Three independent techniques localize expression of transcript afp-11 and its bioactive peptide products to the paired AVK neurons in Ascaris suum: in situ hybridization, immunocytochemistry, and single cell mass spectrometry.

    PubMed

    Jarecki, Jessica L; Viola, India R; Andersen, Kari M; Miller, Andrew H; Ramaker, Megan A; Vestling, Martha M; Stretton, Antony O

    2013-03-20

    We utilized three independent techniques, immunocytochemistry (ICC), single cell mass spectrometry (MS), and in situ hybridization (ISH), to localize neuropeptides and their transcripts in the nervous system of the nematode Ascaris suum . AF11 (SDIGISEPNFLRFa) is an endogenous peptide with potent paralytic effects on A. suum locomotory behavior. A highly specific antibody to AF11 showed robust immunostaining for AF11 in the paired AVK neurons in the ventral ganglion. We traced the processes from the AVK neurons into the ventral nerve cord and identified them as ventral cord interneurons. MS and MS/MS of single dissected AVKs detected AF11, two previously characterized peptides (AF25 and AF26), seven novel sequence-related peptides, including several sharing a PNFLRFamide C-terminus, and peptide NY, a peptide with an unrelated sequence. Also present in a subset of AVKs was AF2, a peptide encoded by the afp-4 transcript. By sequencing the afp-11 transcript, we discovered that it encodes AF11, all the AF11-related peptides detected by MS in AVK, and peptide NY. ISH detected the afp-11 transcript in AVK neurons, consistent with other techniques. ISH did not detect afp-11 in the ALA neuron, although both ICC and MS found AF11 in ca. 30% of ALAs. All 10 AF11-related peptides reduced acetylcholine-induced muscle contraction, but they differed in their rate of reversal of inhibition after removal of the peptide. PMID:23509978

  12. The aggressive nature of the odontogenic keratocyst: is it a benign cystic neoplasm? Part 3. Immunocytochemistry of cytokeratin and other epithelial cell markers.

    PubMed

    Shear, Mervyn

    2002-07-01

    Numerous studies of keratin expression by the more common odontogenic cysts were done to determine whether patterns of cytokeratin staining could provide accurate diagnostic markers for the different varieties; to see whether comparative studies with oral mucosa and developing odontogenic epithelium could explain the pathogenesis of the cysts; and whether cytokeratin patterns could provide clues in elucidating the aggressive nature of the OKC. This review was a complex task with a range of at least 19 different cytokeratins being studied and also a broad range of antibodies in use for the same cytokeratin or group of cytokeratins. Moreover, there was not always standardisation of laboratory techniques in the selection and preparation of material. These difficulties were, in general, recognised by the different workers in the field, particularly when there was disagreement on results and caution was expressed about drawing conclusions from some positive findings. It would be fair to conclude that cytokeratin immunocytochemistry has not advanced to any meaningful extent, its use as a diagnostic marker for the OKC nor in eludidating its pathogenesis. With regard to OKC behaviour, it has been pointed out that there was strong reaction of OKC lining for keratin 16, a cytokeratin that has been associated with high proliferative activity. Yet other studies have also shown keratin 16 expression in dentigerous and radicular cysts. Differences in cytokeratin, EMA and CEA immunocytochemical reactivity between the parakeratinised and orthokeratinised varieties of cyst were demonstrated and the suggestion made that the orthokeratinised type has a considerably less aggressive behaviour, is a different entity and should bear a different name. Furthermore, Ki67 positive cells in the parakeratinised OKC linings were considerably more frequent than in the orthokeratinised linings.OKC, dentigerous and radicular cyst epithelium reacted positively for epithelial growth factor receptor

  13. The role of immunocytochemistry in diagnostic pathology.

    PubMed Central

    Mason, D Y; Gatter, K C

    1987-01-01

    This review suggests that immunocytochemistry in diagnostic pathology can be performed using relatively small panels of antibodies and that it should be reserved for situations in which, for one reason or another, the pathologist cannot exert his or her conventional diagnostic skills. Examples include the diagnosis of tumours the true nature of which is uncertain because of anaplasia or poor morphological preservation; the demonstration of small numbers of cells which are otherwise too rare to be recognised in conventionally stained preparations; and the immunophenotyping of non-Hodgkin's lymphomas. Recently progress has been made in the context of non-Hodgkin's lymphomas by the development of monoclonal antibodies that detect T and B cell associated markers in paraffin wax sections. Most of these reagents, however, recognise either lineage associated (but not lineage specific) variants of the leucocyte common antigen CD45, or antigens that are poorly characterised. A recent promising development has therefore been the demonstration that polyclonal antisera raised against the CD3/T3 T cell specific marker (purified by affinity chromatography) are suitable for staining T cells in paraffin sections. This approach will hopefully enable antibodies to be produced which react with other well defined white cell associated markers in routine biopsy material. Images Fig 1 Fig 3 Fig 6 Fig 7 Fig 8 PMID:3312298

  14. Bilateral renal T-cell lymphoma with hepatic infiltration and secondary polycythemia in a dog: Utility of cytology slides

    PubMed Central

    Froment, Rémi; Gara-Boivin, Carolyn

    2015-01-01

    This is a case of bilateral renal T-cell lymphoma associated with secondary erythrocytosis in a dog. This case is distinctive in using clonality combined with immunocytochemistry to support the diagnosis, thus emphasizing the utility of cytology slides when histology is unavailable. This combination may be a unique canine lymphoma entity. PMID:26663927

  15. Neuroanatomy and immunocytochemistry of the median neuroendocrine cells of the subesophageal ganglion of the tobacco hawkmoth, Manduca sexta: immunoreactivities to PBAN and other neuropeptides.

    PubMed

    Davis, N T; Homberg, U; Teal, P E; Altstein, M; Agricola, H J; Hildebrand, J G

    1996-10-15

    The median neuroendocrine cells of the subesophageal ganglion, important components of the neuroendocrine system of the tobacco hawkmoth, Manduca sexta, have not been well investigated. Therefore, we studied the anatomy of these cells by axonal backfills and characterized their peptide immunoreactivities. Both larvae and adults were examined, and developmental changes in these neuroendocrine cells were followed. Processes of the median neuroendocrine cells project to terminations in the corpora cardiaca via the third and the ventral nerves of this neurohemal organ, but the ventral nerve of the corpus cardiacum is the principal neurohemal surface for this system. Cobalt backfills of the third cardiacal nerves revealed lateral cells in the maxillary neuromere and a ventro-median pair in the labial neuromere. Backfills of the ventral cardiacal nerves revealed two ventro-median pairs of cells in the mandibular neuromere and two ventro-median triplets in the maxillary neuromere. The efferent projections of these cells are contralateral. The anatomy of the system is basically the same in larvae and adults. The three sets of median neuroendocrine cells are PBAN- and FMRFamide-immunoreactive, but only the mandibular and maxillary cells are proctolin-immunoreactive. During metamorphosis, the mandibular and maxillary cells also acquire CCK-like immunoreactivity and the labial cells become SCP- and sulfakinin-immunoreactive. Characteristics of FMRFamide-like immunostaining suggest that the median neuroendocrine cells may contain one or more of the FLRFamides that have been identified in M. sexta. The mandibular and maxillary neuroendocrine cells appear to produce the same set of hormones, and a somewhat different set of hormones is produced by the labial neuroendocrine cells. Two pairs of interneurons immunologically related to the neurosecretory cells are associated with the median maxillary neuroendocrine cells. These cells are PBAN-, FMRFamide-, SCP-, and sulfakinin

  16. Effects of spaceflight in the adductor longus muscle of rats flown in the Soviet Biosatellite COSMOS 2044. A study employing neural cell adhesion molecule (N-CAM) immunocytochemistry and conventional morphological techniques (light and electron microscopy)

    NASA Technical Reports Server (NTRS)

    D'Amelio, F.; Daunton, N. G.

    1992-01-01

    The effects of spaceflight upon the "slow" muscle adductor longus were examined in rats flown in the Soviet Biosatellite COSMOS 2044. The techniques employed included standard methods for light microscopy, neural cell adhesion molecule (N-CAM) immunocytochemistry and electron microscopy. Light microscopic observations revealed myofiber atrophy and segmental necrosis accompanied by cellular infiltrates composed of macrophages, leukocytes and mononuclear cells. Neural cell adhesion molecule immunoreactivity (N-CAM-IR) was seen on the myofiber surface and in regenerating myofibers. Ultrastructural alterations included Z band streaming, disorganization of myofibrillar architecture, sarcoplasmic degradation, extensive segmental necrosis with apparent preservation of the basement membrane, degenerative phenomena of the capillary endothelium and cellular invasion of necrotic areas. Regenerating myofibers were identified by the presence of increased amounts of ribosomal aggregates and chains of polyribosomes associated with myofilaments. The principal electron microscopic changes of the neuromuscular junctions showed axon terminals with a decrease or absence of synaptic vesicles replaced by microtubules and neurofilaments, degeneration of axon terminals, vacant axonal spaces and changes suggestive of axonal sprouting. The present observations suggest that alterations such as myofibrillar disruption and necrosis, muscle regeneration and denervation and synaptic remodeling at the level of the neuromuscular junction may take place during spaceflight.

  17. The immunocytochemistry of cytokeratin in fish tissues.

    PubMed

    Bunton, T E

    1993-09-01

    An increasing interest in fish species as sentinels of environmental pollution and in carcinogenesis research has led to the identification of diagnostically challenging neoplasms of uncertain cellular origin and the need for additional diagnostic methods. To determine the potential of using commercially available antibodies to intermediate filament proteins on paraffin-embedded fish tissues for immunocytochemistry in tumor diagnosis, the application of three antikeratin antibodies to normal adult tissues from two fish species was assessed. Multiple tissues from 12-14-in. striped bass (Morone saxatilis) and 6-month-old medaka (Oryzias latipes) of both sexes were fixed in Bouin's or formalin fixatives. Formalin-fixed neoplasms from several mammalian species, including cat, dog, hedgehog (Atelerix albiventris, Erinaceus europaeus), rhesus macaque (Macaca mulatta), and sloth bear (Melursus ursinus), were also used as positive controls. Using a strepavidin horseradish peroxidase method on paraffin-embedded tissues, the broad spectrum antibodies AE1/AE3 (Boehringer Mannheim, Indianapolis, IN) and MAK-6 (Triton Biosciences, Alameda, CA), which recognize most of the 19 human cytokeratins, and CAM 5.2 (Becton Dickinson, Mountain View, CA), which recognizes cytokeratins present in human liver, were used as primary antibodies. Epithelia from skin, gills, cornea, bile ducts, renal tubules, gastrointestinal tract, and thymus were strongly positive with AE1/AE3 and MAK-6 in striped bass, but nonepithelial tissues such as bone and muscle were negative. Skin, gills, cornea, and portions of the gastrointestinal tract were strongly positive in medaka with the same antibodies, whereas bile duct, renal, and intestinal epithelia were less so. Tissue digestion improved the intensity of staining, and fixation with Bouin's fixative improved results somewhat compared with formalin fixation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7505508

  18. p16INK4a immunocytochemistry on cell blocks as an adjunct to cervical cytology: Potential reflex testing on specially prepared cell blocks from residual liquid-based cytology specimens

    PubMed Central

    Shidham, Vinod B.; Mehrotra, Ravi; Varsegi, George; D'Amore, Krista L.; Hunt, Bryan; Narayan, Raj

    2011-01-01

    Background: p16 INK4a (p16) is a well-recognized surrogate molecular marker for human papilloma virus (HPV) related squamous dysplasia. Our hypothesis is that the invasive interventions and related morbidities could be avoided by objective stratification of positive cytologic interpretations by p16 immunostaining of cell block sections of cytology specimens. Materials and Methods: Nuclear immunoreactivity for p16 was evaluated in cell block sections in 133 adequate cases [20 negative for intraepithelial lesion or malignancy, 28 high-grade squamous intraepithelial lesion (HSIL), 50 low-grade squamous intraepithelial lesion (LSIL), 21 atypical squamous cells, cannot exclude HSIL (ASC-H), and 14 atypical squamous cells of undetermined significance (ASCUS)] and analyzed with cervical biopsy results. Results: (a) HSIL cytology (28): 21 (75%) were p16 positive (11 biopsies available — 92% were positive for cervical intraepithelial neoplasia (CIN) 1 and above) and 7 (25%) were p16 negative (3 biopsies available — all showed only HPV with small atypical parakeratotic cells). (b) LSIL cytology (50): 13 (26%) cases were p16 positive (12 biopsies available — all were CIN1 or above) and 37 (74%) were p16 negative (12 biopsies available — all negative for dysplasia. However, 9 (75%) of these biopsies showed HPV). (c) ASC-H cytology (21): 14 (67%) were p16 positive (6 biopsies available — 5 showed CIN 3/Carcinoma in situ/Ca and 1 showed CIN 1 with possibility of under-sampling. Cytomorphologic re-review favored HSIL) and 7 (33%) were p16 negative (5 biopsies available — 3 negative for dysplasia. Remaining 2 cases — 1 positive for CIN 3 and 1 showed CIN 1 with scant ASC-H cells on cytomorphologic re-review with possibility under-sampling in cytology specimen). (d) ASCUS cytology (14): All (100%) were p16 negative on cell block sections of cervical cytology specimen. HPV testing performed in last 6 months in 7 cases was positive in 3 (43%) cases. Conclusion: p16

  19. The Rate of Oxygen Utilization by Cells

    PubMed Central

    Wagner, Brett A.; Venkataraman, Sujatha; Buettner, Garry R.

    2011-01-01

    The discovery of oxygen is considered by some to be the most important scientific discovery of all time – from both physical-chemical/astrophysics and biology/evolution viewpoints. One of the major developments during evolution is the ability to capture dioxygen in the environment and deliver it to each cell in the multicellular, complex mammalian body -- on demand, i.e. just-in-time. Humans use oxygen to extract approximately 2550 Calories (10.4 MJ) from food to meet daily energy requirements. This combustion requires about 22 moles of dioxygen per day, or 2.5 × 10-4 mol s-1. This is an average rate of oxygen utilization of 2.5 × 10-18 mol cell-1 s-1, i.e. 2.5 amol cell-1 s-1. Cells have a wide range of oxygen utilization, depending on cell type, function, and biological status. Measured rates of oxygen utilization by mammalian cells in culture range from <1 to >350 amol cell-1 s-1. There is a loose positive linear correlation of the rate of oxygen consumption (OCR) by mammalian cells in culture with cell volume and cell protein. The use of oxygen by cells and tissues is an essential aspect of the basic redox biology of cells and tissues. This type of quantitative information is fundamental to investigations in quantitative redox biology, especially redox systems biology. PMID:21664270

  20. Gas concentration cells for utilizing energy

    DOEpatents

    Salomon, Robert E.

    1987-01-01

    An apparatus and method for utilizing energy, in which the apparatus may be used for generating electricity or as a heat pump. When used as an electrical generator, two gas concentration cells are connected in a closed gas circuit. The first gas concentration cell is heated and generates electricity. The second gas concentration cell repressurizes the gas which travels between the cells. The electrical energy which is generated by the first cell drives the second cell as well as an electrical load. When used as a heat pump, two gas concentration cells are connected in a closed gas circuit. The first cell is supplied with electrical energy from a direct current source and releases heat. The second cell absorbs heat. The apparatus has no moving parts and thus approximates a heat engine.

  1. Gas concentration cells for utilizing energy

    DOEpatents

    Salomon, R.E.

    1987-06-30

    An apparatus and method are disclosed for utilizing energy, in which the apparatus may be used for generating electricity or as a heat pump. When used as an electrical generator, two gas concentration cells are connected in a closed gas circuit. The first gas concentration cell is heated and generates electricity. The second gas concentration cell repressurizes the gas which travels between the cells. The electrical energy which is generated by the first cell drives the second cell as well as an electrical load. When used as a heat pump, two gas concentration cells are connected in a closed gas circuit. The first cell is supplied with electrical energy from a direct current source and releases heat. The second cell absorbs heat. The apparatus has no moving parts and thus approximates a heat engine. 4 figs.

  2. Experiment K-7-18: Effects of Spaceflight in the Muscle Adductor Longus of Rats Flown in the Soviet Biosatellite Cosmos 2044. Part 1; A Study Employing Neural Cell Adhesion Molecules (N-CAM) Immunocytochemistry and Conventional Morphological Techniques (Light and Electron Microscopy)

    NASA Technical Reports Server (NTRS)

    Daunton, N. G.; DAmelio, F.; Wu, L.; Ilyina-Kakueva, E. I.; Krasnov, I. B.; Hyde, T. M.; Sigworth, S. K.

    1994-01-01

    The effects of spaceflight upon the 'slow' muscle adductor longus was examined in rats flown in the Soviet Biosatellite COSMOS 2044. Three groups - synchronous, vivarium and basal served as controls. The techniques employed included standard methods for light microscopy, N-CAM immunocytochemistry and electron microscopy. Light microscopic observations revealed myofiber atrophy, contraction bands and segmental necrosis accompanied by cellular infiltrates composed of macrophages, leucocytes and mononuclear cells. N-CAM immunoreactivity was seen (N-CAM-IR) on the myofiber surface, satellite cells and in regenerating myofibers reminiscent of myotubes. Ultrastructural alterations included Z band streaming, disorganization of myofibrillar architecture, sarcoplasmic degradation, extensive segmental necrosis with preservation of the basement membrane, degenerative phenomena of the capillary endothelium and cellular invasion of necrotic areas. Regenerating myofibers were identified by the presence of increased amounts of ribosomal aggregates and chains of polyribosomes associated with myofilaments that displayed varied distributive patterns. The principal electron microscopic changes of the neuromuscular junctions consisted of a decrease or absence of synaptic vesicles, degeneration of axon terminals, increased number of microtubules, vacant axonal spaces and axonal sprouting. The present observations indicate that major alterations such as myofibrillar disruption and necrosis, muscle regeneration and denervation and synaptic remodeling at the level of the neuromuscular junction may take place during spaceflight.

  3. Fuel cell power system for utility vehicle

    SciTech Connect

    Graham, M.; Barbir, F.; Marken, F.; Nadal, M.

    1996-12-31

    Based on the experience of designing and building the Green Car, a fuel cell/battery hybrid vehicle, and Genesis, a hydrogen/oxygen fuel cell powered transporter, Energy Partners has developed a fuel cell power system for propulsion of an off-road utility vehicle. A 10 kW hydrogen/air fuel cell stack has been developed as a prototype for future mass production. The main features of this stack are discussed in this paper. Design considerations and selection criteria for the main components of the vehicular fuel cell system, such as traction motor, air compressor and compressor motor, hydrogen storage and delivery, water and heat management, power conditioning, and control and monitoring subsystem are discussed in detail.

  4. Differential diagnosis between mesothelioma and adenocarcinoma: a multimodal approach based on ultrastructure and immunocytochemistry

    SciTech Connect

    Bedrossian, C.W.; Bonsib, S.; Moran, C. )

    1992-05-01

    Most compensations for asbestos-related deaths secondary to cancer center around mesothelioma and bronchogenic carcinoma. The differential diagnosis between mesothelioma and adenocarcinoma is a common and troublesome one, necessitating the correlation between clinical history, radiographic findings, and pathologic examination of tissues and cells. We describe a multimodal approach based on the use of routine and special stains, immunocytochemistry, and electron microscopy for distinguishing between mesothelioma and adenocarcinoma. Once a malignant diagnosis is arrived at by careful pathological examination, the tumor is classified as mesothelioma if mesothelial cells are identified as the constituent cells of the neoplasm. Mesothelial cells are recognized by (1) their main ultrastructural features: slender and elongated microvilli, abundant intermediate filaments, and lacking secretory granules; and (2) their characteristic immunocytochemical reactivity: positivity for cytokeratin, EMA, and vimentin, and negativity for carcinoembryonic antigen (CEA), B72-3, Leu-M1, and other gland-cell markers. A variety of methods have been attempted in an effort to distinguish between reactive and malignant mesothelial cells. In practice, however, such distinction depends more on experience and expertise than in any fool-proof ancillary tests. A number of these tests are discussed along with the illustration of classical and unusual examples of mesothelioma and other pleural tumors.

  5. Cell blocks in cytopathology: a review of preparative methods, utility in diagnosis and role in ancillary studies.

    PubMed

    Jain, D; Mathur, S R; Iyer, V K

    2014-12-01

    The cell block (CB) is a routine procedure in cytopathology that has gained importance because of its pivotal role in diagnosis and ancillary studies. There is no precise review in the published literature that deals with the various methods of preparation of CB, its utility in diagnosis, immunocytochemistry (ICC) or molecular testing, and its drawbacks. An extensive literature search on CB in cytology using internet search engines was performed for this review employing the following keywords: cell block, cytoblock, cytology, cytopathology, methods, preparation, fixatives, diagnostic yield, ancillary and molecular studies. Ever since its introduction more than a century ago, the CB technique has undergone numerous modifications to improve the quality of the procedure; however, the overall principle remains the same in each method. CBs can be prepared from virtually all varieties of cytological samples. In today's era of personalized medicine, cytological specimens, including CBs, augment the utility of cytological samples in analysing the molecular alterations as effectively as surgical biopsies or resection specimens. With the availability of molecular targeted therapy for many cancers, a large number of recent studies have used cytological material or CBs for molecular characterization. The various techniques of CB preparation with different fixatives, their advantages and limitations, and issues of diagnostic yield are discussed in this review. PMID:25113785

  6. Just cool it! Cryoprotectant anti-freeze in immunocytochemistry and in situ hybridization.

    PubMed

    Hoffman, Gloria E; Le, Wei Wei

    2004-03-01

    Immunohistochemical techniques offer specificity as well as flexibility for visualizing antigens. Their use with freely floating sections provides a high signal-to-noise ratio and has become a gold standard for brain and a number of other tissues. Yet this approach initially suffered from inability to keep the antigenicity in tissue sections and required immediate processing of all cut sections. Use of sucrose solutions enabled storage at refrigerator temperatures for a few days but longer-term storage was risky and either bacterial/fungal growth or evaporation of the storage solution compromised the integrity of the tissue. Our discovery 25 years ago that tissue sections can be stored for many years at -20 degrees C in an anti-freeze cryoprotectant solution with no loss of antigenicity solved this problem and has become widely used. More recently the utility of tissue stored for many years in anti-freeze cryoprotectant was pushed to new levels by testing new non-radioactive in situ hybridization (ISH) techniques that are based on modern immunocytochemistry. This review touches upon these advances in immunocytochemical technology using examples from neuroscience applications. PMID:15134865

  7. Keratin proteins in human lung carcinomas. Combined use of morphology, keratin immunocytochemistry, and keratin immunoprecipitation.

    PubMed Central

    Banks-Schlegel, S. P.; McDowell, E. M.; Wilson, T. S.; Trump, B. F.; Harris, C. C.

    1984-01-01

    Light-microscopic immunocytochemistry and electron microscopy demonstrated that adenocarcinomas (AC) and squamous cell (epidermoid) carcinomas (SCCs) of human lung contained keratin proteins in the form of tonofilament bundles. However, moderately differentiated (md) SCCs contained abundant keratin, whereas poorly differentiated (pd) SCCs and all ACs contained lesser amounts. Lung tumors with the diagnosis of AC or SCC, as defined by WHO criteria, were also analyzed by immunoprecipitation techniques for the presence of keratin proteins. Regardless of the degree of tumor differentiation, SCCs contained a 44 kd keratin which was lacking in ACs. Interestingly, normal bronchial epithelium also contained the same 44 kd keratin. In addition, as SCCs became more differentiated, they exhibited even greater differences in the profile of synthesized keratins. Specifically, the relative abundance of the intermediate-sized keratins (57 and 59 kd) was increased in the md SCCs. Although keratin protein patterns appear to be a valuable adjunct in distinguishing AC from SCC, their usefulness as a diagnostic tool will require survey of a larger number of poorly differentiated tumors. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:6198920

  8. A novel triple-color detection procedure for brightfield microscopy, combining in situ hybridization with immunocytochemistry.

    PubMed

    Speel, E J; Jansen, M P; Ramaekers, F C; Hopman, A H

    1994-10-01

    We describe a fast light microscopic procedure for the simultaneous enzyme cytochemical detection of three different DNA target sequences in contrasting colors in both interphase and metaphase cell preparations. Chromosome-specific DNA probes labeled with either biotin, digoxygenin, or fluorescein were hybridized as a mixture and detected clearly and accurately by precipitates of the horseradish peroxidase-diaminobenzidine (PO-DAB, brown color), alkaline phosphatase-Fast Red (APase-Fast Red, red color), or horseradish peroxidase-tetramethylbenzidine (PO-TMB, green color) reaction, respectively. The PO-TMB reaction product was stabilized effectively by the addition of sodium tungstate to the reaction mixture, thus making the PO-TMB reaction now generally applicable to in situ hybridization (ISH). To avoid mixing of the precipitates of the two PO reactions used in the triple-color ISH method, the first detected PO activity was always completely inactivated by a mild acid treatment before the second one was applied. Finally, the cell preparations were embedded in a thin protein layer cross-linked by formaldehyde to ensure permanent stabilization of the enzyme reaction products and optimal visualization of color contrast. The triple-color ISH detection procedure could be combined with beta-galactosidase-5-bromo-4-chloro-3-indolyl-beta- D-galactoside (beta-Gal-BCIG) immunocytochemistry (ICC), leading to the simultaneous localization of multiple DNA targets and a protein target in the same cell. The described procedure may therefore be a valuable tool in the areas of cytogenetics, cell biology, and molecular pathology. PMID:7930513

  9. Quantitative immunocytochemistry at the ultrastructural level: a stereology-based approach to molecular nanomorphomics.

    PubMed

    Mayhew, Terry M

    2015-04-01

    Biological systems span multiple levels of structural organisation from the macroscopic, via the microscopic, to the nanoscale. Therefore, comprehensive investigation of systems biology requires application of imaging modalities that reveal structure at multiple resolution scales. Nanomorphomics is the part of morphomics devoted to the systematic study of functional morphology at the nanoscale and an important element of its achievement is the combination of immunolabelling and transmission electron microscopy (TEM). The ultimate goal of quantitative immunocytochemistry is to estimate numbers of target molecules (usually peptides, proteins or protein complexes) in biological systems and to map their spatial distributions within them. Immunogold cytochemistry utilises target-specific affinity markers (primary antibodies) and visualisation aids (e.g., colloidal gold particles or silver-enhanced nanogold particles) to detect and localise target molecules at high resolution in intact cells and tissues. In the case of post-embedding labelling of ultrathin sections for TEM, targets are localised as a countable digital readout by using colloidal gold particles. The readout comprises a spatial distribution of gold particles across the section and within the context of biological ultrastructure. The observed distribution across structural compartments (whether volume- or surface-occupying) represents both specific and non-specific labelling; an assessment by eye alone as to whether the distribution is random or non-random is not always possible. This review presents a coherent set of quantitative methods for testing whether target molecules exhibit preferential and specific labelling of compartments and for mapping the same targets in two or more groups of cells as their TEM immunogold-labelling patterns alter after experimental manipulation. The set also includes methods for quantifying colocalisation in multiple-labelling experiments and mapping absolute numbers of

  10. Energy utilization and efficiency analysis for hydrogen fuel cell vehicles

    NASA Astrophysics Data System (ADS)

    Moore, R. M.; Hauer, K. H.; Ramaswamy, S.; Cunningham, J. M.

    This paper presents the results of an energy analysis for load-following versus battery-hybrid direct-hydrogen fuel cell vehicles. The analysis utilizes dynamic fuel cell vehicle simulation tools previously presented [R.M. Moore, K.H. Hauer, J. Cunningham, S. Ramaswamy, A dynamic simulation tool for the battery-hybrid hydrogen fuel cell vehicle, Fuel Cells, submitted for publication; R.M. Moore, K.H. Hauer, D.J. Friedman, J.M. Cunningham, P. Badrinarayanan, S.X. Ramaswamy, A. Eggert, A dynamic simulation tool for hydrogen fuel cell vehicles, J. Power Sources, 141 (2005) 272-285], and evaluates energy utilization and efficiency for standardized drive cycles used in the US, Europe and Japan.

  11. Enhanced methanol utilization in direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming; Gottesfeld, Shimshon

    2001-10-02

    The fuel utilization of a direct methanol fuel cell is enhanced for improved cell efficiency. Distribution plates at the anode and cathode of the fuel cell are configured to distribute reactants vertically and laterally uniformly over a catalyzed membrane surface of the fuel cell. A conductive sheet between the anode distribution plate and the anodic membrane surface forms a mass transport barrier to the methanol fuel that is large relative to a mass transport barrier for a gaseous hydrogen fuel cell. In a preferred embodiment, the distribution plate is a perforated corrugated sheet. The mass transport barrier may be conveniently increased by increasing the thickness of an anode conductive sheet adjacent the membrane surface of the fuel cell.

  12. The market for utility-scale fuel cell plants

    NASA Astrophysics Data System (ADS)

    Watanabe, Yasuo; Matsumoto, Masaru; Takasu, Kazuhiko

    This paper is devoted to a survey of the current technology and future market for utility-scale fuel cell plants. The phosphoric acid fuel cell (PAFC) is entering into the stage where it is practically available for use with natural gas. Large capacity plants such as 11, 5 and 1 MW have been installed and operated in Italy and Japan. Their efficiency ranges from 36 to 42%. The molten carbonate fuel cell (MCFC) is in the demonstrating stage, both the fuel cell and the balance-of-plant (BOP) for natural gas. Demonstration plants of 2 and 1 MW have been under construction in the USA and Japan. Their efficiency will range from 40 to 50%. The solid oxide fuel cell (SOFC) is in the experimental stage around 100 kW for co-generation. Its conceptual system design has been conducted for both centralized and dispersed power plant in a cooperation with Westinghouse and NEDO. A market survey is now considered on the basis that future fuel cells will run for around 40 000 h in a stable manner with competitive performance. The market for fuel cells will be roughly at 2000 MW in Japan by the year 2010. Half of them will be installed for electric companies on the utility scale. The market will be shared between PAFC and MCFC by 10 and 90%, respectively. Current technologies have not reached the stage to precisely forecast when fuel cells will be entering into the market on a utility scale. At the present time, it is worthwhile to consider how the technological and economic requirements will be definitely achieved. After achieving these requirements, fuel cells will be positively introduced and socially accepted as the best energy converting option to save energy and environmental impact. Further efforts will be devoted to meeting the market from the technological and economic aspects.

  13. Electric utility acid fuel cell stack technology advancement

    NASA Technical Reports Server (NTRS)

    Congdon, J. V.; Goller, G. J.; Greising, G. J.; Obrien, J. J.; Randall, S. A.; Sandelli, G. J.; Breault, R. D.; Austin, G. W.; Bopse, S.; Coykendall, R. D.

    1984-01-01

    The principal effort under this program was directed at the fuel cell stack technology required to accomplish the initial feasibility demonstrations of increased cell stack operating pressures and temperatures, increased cell active area, incorporation of the ribbed substrate cell configuration at the bove conditions, and the introduction of higher performance electrocatalysts. The program results were successful with the primary accomplishments being: (1) fabrication of 10 sq ft ribbed substrate, cell components including higher performing electrocatalysts; (2) assembly of a 10 sq ft, 30-cell short stack; and (3) initial test of this stack at 120 psia and 405 F. These accomplishments demonstrate the feasibility of fabricating and handling large area cells using materials and processes that are oriented to low cost manufacture. An additional accomplishment under the program was the testing of two 3.7 sq ft short stacks at 12 psia/405 F to 5400 and 4500 hours respectively. These tests demonstrate the durability of the components and the cell stack configuration to a nominal 5000 hours at the higher pressure and temperature condition planned for the next electric utility power plant.

  14. Correlation between SD-OCT, immunocytochemistry and functional findings in an animal model of retinal degeneration

    PubMed Central

    Cuenca, Nicolás; Fernández-Sánchez, Laura; Sauvé, Yves; Segura, Francisco J.; Martínez-Navarrete, Gema; Tamarit, José Manuel; Fuentes-Broto, Lorena; Sanchez-Cano, Ana; Pinilla, Isabel

    2014-01-01

    Purpose: The P23H rhodopsin mutation is an autosomal dominant cause of retinitis pigmentosa (RP). The degeneration can be tracked using different anatomical and functional methods. In our case, we evaluated the anatomical changes using Spectral-Domain Optical Coherence Tomography (SD-OCT) and correlated the findings with retinal thickness values determined by immunocytochemistry.Methods: Pigmented rats heterozygous for the P23H mutation, with ages between P18 and P180 were studied. Function was assessed by means of optomotor testing and ERGs. Retinal thicknesses measurements, autofluorescence and fluorescein angiography were performed using Spectralis OCT. Retinas were studied by means of immunohistochemistry. Results: Between P30 and P180, visual acuity decreased from 0.500 to 0.182 cycles per degree (cyc/deg) and contrast sensitivity decreased from 54.56 to 2.98 for a spatial frequency of 0.089 cyc/deg. Only cone-driven b-wave responses reached developmental maturity. Flicker fusions were also comparable at P29 (42 Hz). Double flash-isolated rod-driven responses were already affected at P29. Photopic responses revealed deterioration after P29.A reduction in retinal thicknesses and morphological modifications were seen in OCT sections. Statistically significant differences were found in all evaluated thicknesses. Autofluorescence was seen in P23H rats as sparse dots. Immunocytochemistry showed a progressive decrease in the outer nuclear layer (ONL), and morphological changes. Although anatomical thickness measures were significantly lower than OCT values, there was a very strong correlation between the values measured by both techniques.Conclusions: In pigmented P23H rats, a progressive deterioration occurs in both retinal function and anatomy. Anatomical changes can be effectively evaluated using SD-OCT and immunocytochemistry, with a good correlation between their values, thus making SD-OCT an important tool for research in retinal degeneration. PMID:25565976

  15. Utility of transmission electron microscopy in small round cell tumors.

    PubMed

    Kim, Na Rae; Ha, Seung Yeon; Cho, Hyun Yee

    2015-03-01

    Small round cell tumors (SRCTs) are a heterogeneous group of neoplasms composed of small, primitive, and undifferentiated cells sharing similar histology under light microscopy. SRCTs include Ewing sarcoma/peripheral neuroectodermal tumor family tumors, neuroblastoma, desmoplastic SRCT, rhabdomyosarcoma, poorly differentiated round cell synovial sarcoma, mesenchymal chondrosarcoma, small cell osteosarcoma, small cell malignant peripheral nerve sheath tumor, and small cell schwannoma. Non-Hodgkin's malignant lymphoma, myeloid sarcoma, malignant melanoma, and gastrointestinal stromal tumor may also present as SRCT. The current shift towards immunohistochemistry and cytogenetic molecular techniques for SRCT may be inappropriate because of antigenic overlapping or inconclusive molecular results due to the lack of differentiation of primitive cells and unavailable genetic service or limited moleculocytogenetic experience. Although usage has declined, electron microscopy (EM) remains very useful and shows salient features for the diagnosis of SRCTs. Although EM is not always required, it provides reliability and validity in the diagnosis of SRCT. Here, the ultrastructural characteristics of SRCTs are reviewed and we suggest that EM would be utilized as one of the reliable modalities for the diagnosis of undifferentiated and poorly differentiated SRCTs. PMID:25812730

  16. Utility of Transmission Electron Microscopy in Small Round Cell Tumors

    PubMed Central

    Kim, Na Rae; Ha, Seung Yeon; Cho, Hyun Yee

    2015-01-01

    Small round cell tumors (SRCTs) are a heterogeneous group of neoplasms composed of small, primitive, and undifferentiated cells sharing similar histology under light microscopy. SRCTs include Ewing sarcoma/peripheral neuroectodermal tumor family tumors, neuroblastoma, desmoplastic SRCT, rhabdomyosarcoma, poorly differentiated round cell synovial sarcoma, mesenchymal chondrosarcoma, small cell osteosarcoma, small cell malignant peripheral nerve sheath tumor, and small cell schwannoma. Non-Hodgkin’s malignant lymphoma, myeloid sarcoma, malignant melanoma, and gastrointestinal stromal tumor may also present as SRCT. The current shift towards immunohistochemistry and cytogenetic molecular techniques for SRCT may be inappropriate because of antigenic overlapping or inconclusive molecular results due to the lack of differentiation of primitive cells and unavailable genetic service or limited moleculocytogenetic experience. Although usage has declined, electron microscopy (EM) remains very useful and shows salient features for the diagnosis of SRCTs. Although EM is not always required, it provides reliability and validity in the diagnosis of SRCT. Here, the ultrastructural characteristics of SRCTs are reviewed and we suggest that EM would be utilized as one of the reliable modalities for the diagnosis of undifferentiated and poorly differentiated SRCTs. PMID:25812730

  17. Indirect myosin immunocytochemistry for the identification of fibre types in equine skeletal muscle

    NASA Technical Reports Server (NTRS)

    Sinha, A. K.; Rose, R. J.; Pozgaj, I.; Hoh, J. F.

    1992-01-01

    The histochemical ATPase method for muscle fibre typing was first described by Brooke and Kaiser in 1970. However, problems have been found with the subdivision of type II fibres using this technique. To determine whether indirect myosin immunocytochemistry using anti-slow (5-4D), anti-fast (1A10) and anti-fast red (5-2B) monoclonal antibodies with cross reactivity for type I, II and IIa fibres, respectively, in a number of species, could identify three fibre types in equine skeletal muscle, data on fibre type composition and fibre size obtained using the two different techniques were compared. Results indicate that different myosin heavy chains can coexist in single equine muscle fibres. Type I and type II fibres were identified by immunocytochemistry, but subdivision of type II fibres was not possible. Although the percentage of type I and type II fibres was not significantly different for the two techniques, a few fibres reacted with both the 1A10 and 5-4D antibodies.

  18. Fuel Cells Utilizing Oxygen From Air at Low Pressures

    NASA Technical Reports Server (NTRS)

    Cisar, Alan; Boyer, Chris; Greenwald, Charles

    2006-01-01

    A fuel cell stack has been developed to supply power for a high-altitude aircraft with a minimum of air handling. The fuel cell is capable of utilizing oxygen from ambient air at low pressure with no need for compression. For such an application, it is advantageous to take oxygen from the air (in contradistinction to carrying a supply of oxygen onboard), but it is a challenging problem to design a fuel-cell stack of reasonable weight that can generate sufficient power while operating at reduced pressures. The present fuel-cell design is a response to this challenge. The design features a novel bipolar plate structure in combination with a gas-diffusion structure based on a conductive metal core and a carbon gas-diffusion matrix. This combination makes it possible for the flow fields in the stack to have a large open fraction (ratio between open volume and total volume) to permit large volumes of air to flow through with exceptionally low backpressure. Operations at reduced pressure require a corresponding increase in the volume of air that must be handled to deliver the same number of moles of oxygen to the anodes. Moreover, the increase in the open fraction, relative to that of a comparable prior fuel-cell design, reduces the mass of the stack. The fuel cell has been demonstrated to operate at a power density as high as 105 W/cm2 at an air pressure as low as 2 psia (absolute pressure 14 kPa), which is the atmospheric pressure at an altitude of about 50,000 ft ( 15.2 km). The improvements in the design of this fuel cell could be incorporated into designs of other fuel cells to make them lighter in weight and effective at altitudes higher than those of prior designs. Potential commercial applications for these improvements include most applications now under consideration for fuel cells.

  19. Utility of hydroxyurea in mast cell activation syndrome

    PubMed Central

    2013-01-01

    Mast cell activation syndrome (MCAS) is a relatively recently recognized cause of chronic multisystem polymorbidity of a generally inflammatory theme. Patients with MCAS often report migratory soft tissue and/or bone pain which frequently responds poorly to typical (narcotic and non-narcotic) analgesics as well as atypical analgesics such as antidepressants and anticonvulsants. Hydroxyurea (HU) is an oral ribonucleotide reductase inhibitor commonly used in the treatment of chronic myeloproliferative neoplasms and sickle cell anemia. HU has been used to treat systemic mastocytosis, sometimes effecting improvement in MC activation symptoms but not tumor burden, suggesting potential utility of the drug in MCAS, too. Reported here are five cases of successful use of relatively low-dose HU in MCAS to reduce symptoms including previously refractory soft tissue and/or bone pain. HU may be useful in treating mediator symptoms in MCAS, but further study is needed to define optimal dosing strategies and patient subpopulations most likely to benefit. PMID:24192267

  20. A flexible micro biofuel cell utilizing hydrogel containing ascorbic acid

    NASA Astrophysics Data System (ADS)

    Goto, Hideaki; Fukushi, Yudai; Nishioka, Yasushiro

    2014-11-01

    This paper reports on a biofuel cell with a dimension of 13×24 mm2 fabricated on a flexible polyimide substrate. I its porous carbon-coated platinum (Pt) electrodes of 3 mm in width and 10 mm in length were fabricated using photolithography and screen printing techniques. Porous carbon was deposited by screen printing of carbon black ink on the Pt electrode surfaces in order to increase the effective electrode surface area and to absorb more enzymes on the electrode surfaces. It utilizes a solidified ascorbic acid (AA) aqueous solution in an agarose hydrogel to increase the portability. The maximum power and power density for the biofuel cell with the fuel unit containing 100 mM AA were 0.063 μW and 0.21 μW/cm2 at 0.019 V, respectively.

  1. Brain c-Fos immunocytochemistry and cytochrome oxidase histochemistry after a fear conditioning task.

    PubMed

    Conejo, Nélida M; González Pardo, Héctor; López, Matías; Cantora, Raúl; Arias, Jorge L

    2007-05-01

    The involvement of the basolateral and the medial amygdala in fear conditioning was evaluated using different markers of neuronal activation. The method described here is a combination of cytochrome oxidase (CO) histochemistry and c-Fos immunocytochemistry on fresh frozen brain sections. Freezing behavior was used as an index of auditory and contextual fear conditioning. As expected, freezing scores were significantly higher in rats exposed to tone-shock pairings in a distinctive environment (conditioned; COND), as compared to rats that did not receive any shocks (UNCD). CO labeling was increased in the basolateral and medial amygdala of the COND group. Conversely, c-Fos expression in the basolateral and medial amygdala was lower in the COND group as compared to the UNCD group. Furthermore, c-Fos expression was particularly high in the medial amygdala of the UNCD group. The data provided by both techniques indicate that these amygdalar nuclei could play different roles on auditory and contextual fear conditioning. PMID:17425902

  2. Direct Carbon Fuel Cell System Utilizing Solid Carbonaceous Fuels

    SciTech Connect

    Turgut Gur

    2010-04-30

    This 1-year project has achieved most of its objective and successfully demonstrated the viability of the fluidized bed direct carbon fuel cell (FB-DCFC) approach under development by Direct Carbon technologies, LLC, that utilizes solid carbonaceous fuels for power generation. This unique electrochemical technology offers high conversion efficiencies, produces proportionately less CO{sub 2} in capture-ready form, and does not consume or require water for gasification. FB-DCFC employs a specialized solid oxide fuel cell (SOFC) arrangement coupled to a Boudouard gasifier where the solid fuel particles are fluidized and reacted by the anode recycle gas CO{sub 2}. The resulting CO is electrochemically oxidized at the anode. Anode supported SOFC structures employed a porous Ni cermet anode layer, a dense yttria stabilized zirconia membrane, and a mixed conducting porous perovskite cathode film. Several kinds of untreated solid fuels (carbon and coal) were tested in bench scale FBDCFC prototypes for electrochemical performance and stability testing. Single cells of tubular geometry with active areas up to 24 cm{sup 2} were fabricated. The cells achieved high power densities up to 450 mW/cm{sup 2} at 850 C using a low sulfur Alaska coal char. This represents the highest power density reported in the open literature for coal based DCFC. Similarly, power densities up to 175 mW/cm{sup 2} at 850 C were demonstrated with carbon. Electrical conversion efficiencies for coal char were experimentally determined to be 48%. Long-term stability of cell performance was measured under galvanostatic conditions for 375 hours in CO with no degradation whatsoever, indicating that carbon deposition (or coking) does not pose any problems. Similar cell stability results were obtained in coal char tested for 24 hours under galvanostatic conditions with no sign of sulfur poisoning. Moreover, a 50-cell planar stack targeted for 1 kW output was fabricated and tested in 95% CO (balance CO{sub 2

  3. Immunocytochemistry for the heavy chain of the non-muscle myosin IIA as a diagnostic tool for MYH9-related disorders.

    PubMed

    Pecci, Alessandro; Noris, Patrizia; Invernizzi, Rosangela; Savoia, Anna; Seri, Marco; Ghiggeri, Gian Marco; Sartore, Saverio; Gangarossa, Simone; Bizzaro, Nicola; Balduini, Carlo L

    2002-04-01

    May-Hegglin anomaly (MHA), Sebastian syndrome (SBS) and Fechtner syndrome (FTNS) are autosomal-dominant macrothrombocytopenias with Döhle-like leucocyte inclusions. These diseases are due to mutations of the MHY9 gene, encoding the heavy chain of non-muscle myosin IIA (NMMHC-A). We investigated the NMMHC-A localization in blood cells from eight MHA, SBS or FTNS patients with known MYH9 mutations. All the patients showed an altered localization of NMMHC-A in granulocytes and platelets, suggesting that Döhle-like bodies are due to the aggregation of NMMHC-A in the cytoplasm. Therefore, immunocytochemistry for NMMHC-A is a simple and sensitive method to detect pathological phenotypes of granulocytes and platelets in the diagnosis of MYH9-related disorders. PMID:11918549

  4. GROWTH AND METABOLISM OF INDIVIDUAL BACTERIAL CELLS UTILIZING NANOSIMS

    SciTech Connect

    NEALSON, H. K.

    2007-08-03

    This work involved the use of the Nano-SIMS Instrument at Lawrence Livermore Laboratory, in an effort to utilize this unique tool for experiments in Biology. The work consisted primarily of experiments to measure in real time, C and N fixation in cyanobacteria. The work revealed a number of the difficulties in using the nano-SIMS approach with biological material, but with collaboration from a number of individuals at USC and LLNL, major progress was made. The collaborators from LLNL were from the Chemistry Group (Dr. Peter Weber), and the Biology Group (Dr. Jennifer Pett-Ridge). In addition, there were a number of other scientists involved from LLNL. The USC group consisted of Dr. K.H. Nealson, the PI on the grant, Dr. R. Popa, a postdoctoral fellow and research associate at USC, Professor Douglas Capone, and Juliet Finze, a graduate student in biology. Two major experiments were done, both of which yielded new and exciting data. (1) We studied nitrogen and carbon fixation in Anabaena, demonstrating that fixation ofN occurred rapidly in the heterocysts, and that the fixed N was transported rapidly and completely to the vegetative cells. C fixation occurred in the vegetative cells, with labeled C remaining in these cells in support of their growth and metabolism. This work was accepted in the ISME Journal (Nature Publication), and published last month. (2) We studied nitrogen and carbon fixation in Trichodesmium, a non-heterocystous cyanobacterium that also fixes nitrogen. Interestingly, the nitrogen fixation was confined to regions within the filaments that seem to be identical to the so-called cyanophycaen granules. The fixed N is then transported to other parts of the cyanobacterium, as judged by movement of the heavy N throughout the filaments. On the basis of these very exciting results, we have applied for funding from the NSF to continue the collaboration with LLNL. The results of both studies were presented in the summer of 2007 at the Gordon Research

  5. Utilizing FUCCI reporters to understand pluripotent stem cell biology.

    PubMed

    Singh, Amar M; Trost, Robert; Boward, Benjamin; Dalton, Stephen

    2016-05-15

    The fluorescence ubiquitination cell cycle indicator (FUCCI) system provides a powerful method to evaluate cell cycle mechanisms associated with stem cell self-renewal and cell fate specification. By integrating the FUCCI system into human pluripotent stem cells (hPSCs) it is possible to isolate homogeneous fractions of viable cells representative of all cell cycle phases. This method avoids problems associated with traditional tools used for cell cycle analysis such as synchronizing drugs, elutriation and temperature sensitive mutants. Importantly, FUCCI reporters allow cell cycle events in dynamic systems, such as differentiation, to be evaluated. Initial reports on the FUCCI system focused on its strengths in reporting spatio-temporal aspects of cell cycle events in living cells and developmental models. In this report, we describe approaches that broaden the application of FUCCI reporters in PSCs through incorporation of FACS. This approach allows molecular analysis of the cell cycle in stem cell systems that were not previously possible. PMID:26404921

  6. Study of technical and economic feasibility of fuel cell cogeneration applications by electric utilities

    NASA Astrophysics Data System (ADS)

    Ku, W. S.; Wakefield, R. A.

    1981-10-01

    A previous EPRI study showed significant potential penetrations of fuel cells into the future generation mixes of U.S. electric utilities. A new EPRI-sponsored study was conducted to investigate the possible additional benefits of operating these utility-owned fuel cells as cogeneration facilities. Three classes of applications were evaluated: residential and commercial buildings, industrial processes and utility power plants. Incremental breakeven capital costs between cogenerating and electric-only fuel cells were determined with respect to conventional thermal energy supply alternatives. The results showed that there are sufficient economic incentives for fuel cell cogeneration in all three classes of applications.

  7. Human Rhabdomyosarcoma Cell Lines for Rhabdomyosarcoma Research: Utility and Pitfalls

    PubMed Central

    Hinson, Ashley R. P.; Jones, Rosanne; Crose, Lisa E. S.; Belyea, Brian C.; Barr, Frederic G.; Linardic, Corinne M.

    2013-01-01

    Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood and adolescence. Despite intergroup clinical trials conducted in Europe and North America, outcomes for high risk patients with this disease have not significantly improved in the last several decades, and survival of metastatic or relapsed disease remains extremely poor. Accrual into new clinical trials is slow and difficult, so in vitro cell-line research and in vivo xenograft models present an attractive alternative for preclinical research for this cancer type. Currently, 30 commonly used human RMS cell lines exist, with differing origins, karyotypes, histologies, and methods of validation. Selecting an appropriate cell line for RMS research has important implications for outcomes. There are also potential pitfalls in using certain cell lines including contamination with murine stromal cells, cross-contamination between cell lines, discordance between the cell line and its associated original tumor, imposter cell lines, and nomenclature errors that result in the circulation of two or more presumed unique cell lines that are actually from the same origin. These pitfalls can be avoided by testing for species-specific isoenzymes, microarray analysis, assays for subtype-specific fusion products, and short tandem repeat analysis. PMID:23882450

  8. Utilizing Chimeric Antigen Receptors to Direct Natural Killer Cell Activity

    PubMed Central

    Hermanson, David L.; Kaufman, Dan S.

    2015-01-01

    Natural killer (NK) cells represent an attractive lymphocyte population for cancer immunotherapy due to their ability to lyse tumor targets without prior sensitization and without need for human leukocyte antigens-matching. Chimeric antigen receptors (CARs) are able to enhance lymphocyte targeting and activation toward diverse malignancies. CARs consist of an external recognition domain (typically a small chain variable fragment) directed at a specific tumor antigen that is linked with one or more intracellular signaling domains that mediate lymphocyte activation. Most CAR studies have focused on their expression in T cells. However, use of CARs in NK cells is starting to gain traction because they provide a method to redirect these cells more specifically to target refractory cancers. CAR-mediated anti-tumor activity has been demonstrated using NK cell lines, as well as NK cells isolated from peripheral blood, and NK cells produced from human pluripotent stem cells. This review will outline the CAR constructs that have been reported in NK cells with a focus on comparing the use of different signaling domains in combination with other co-activating domains. PMID:25972867

  9. Electrochemical cell utilizing molten alkali metal electrode-reactant

    DOEpatents

    Virkar, Anil V.; Miller, Gerald R.

    1983-11-04

    An improved electrochemical cell comprising an additive-modified molten alkali metal electrode-reactant and/or electrolyte is disclosed. Various electrochemical cells employing a molten alkali metal, e.g., sodium, electrode in contact with a cationically conductive ceramic membrane experience a lower resistance and a lower temperature coefficient of resistance whenever small amounts of selenium are present at the interface of the electrolyte and the molten alkali metal. Further, cells having small amounts of selenium present at the electrolyte-molten metal interface exhibit less degradation of the electrolyte under long term cycling conditions.

  10. Inverted amorphous silicon solar cell utilizing cermet layers

    DOEpatents

    Hanak, Joseph J.

    1979-01-01

    An amorphous silicon solar cell incorporating a transparent high work function metal cermet incident to solar radiation and a thick film cermet contacting the amorphous silicon opposite to said incident surface.

  11. Utilization of oil in soil and water by microbial cells

    SciTech Connect

    Surzhko, L.F.; Yankevich, M.I.; Yakovlev, V.I.

    1995-05-01

    Pure cultures and culture associations actively utilizing aliphatic and aromatic fractions of oil of the Romashkinskoe oil field were selected. Biopreparations based on vermiculite-immobilized active oil-degrading strains were developed. The ability of the preparations to decompose oil in soil and water was shown. The preparation containing an association of yeast and the bacterium Acinetobacter sp. 725 proved most efficient. In field lysimetric experiments, the introduction of the preparations accelerated oil decomposition by up to 65-78% compared to the control. 6 refs., 2 figs., 4 tabs.

  12. Microarray Dot Electrodes Utilizing Dielectrophoresis for Cell Characterization

    PubMed Central

    Yafouz, Bashar; Kadri, Nahrizul Adib; Ibrahim, Fatimah

    2013-01-01

    During the last three decades; dielectrophoresis (DEP) has become a vital tool for cell manipulation and characterization due to its non-invasiveness. It is very useful in the trend towards point-of-care systems. Currently, most efforts are focused on using DEP in biomedical applications, such as the spatial manipulation of cells, the selective separation or enrichment of target cells, high-throughput molecular screening, biosensors and immunoassays. A significant amount of research on DEP has produced a wide range of microelectrode configurations. In this paper; we describe the microarray dot electrode, a promising electrode geometry to characterize and manipulate cells via DEP. The advantages offered by this type of microelectrode are also reviewed. The protocol for fabricating planar microelectrodes using photolithography is documented to demonstrate the fast and cost-effective fabrication process. Additionally; different state-of-the-art Lab-on-a-Chip (LOC) devices that have been proposed for DEP applications in the literature are reviewed. We also present our recently designed LOC device, which uses an improved microarray dot electrode configuration to address the challenges facing other devices. This type of LOC system has the capability to boost the implementation of DEP technology in practical settings such as clinical cell sorting, infection diagnosis, and enrichment of particle populations for drug development. PMID:23857266

  13. Direct Utilization of Coal Syngas in High Temperature Fuel Cells

    SciTech Connect

    Celik, Ismail B.

    2014-10-30

    This EPSCoR project had two primary goals: (i) to build infrastructure and work force at WVU to support long-term research in the area of fuel cells and related sciences; (ii) study effects of various impurities found in coal-syngas on performance of Solid Oxide Fuel Cells (SOFC). As detailed in this report the WVU research team has made significant accomplishments in both of these areas. What follows is a brief summary of these accomplishments: State-of-the-art test facilities and diagnostic tools have been built and put into use. These include cell manufacturing, half-cell and full-cell test benches, XPS, XRD, TEM, Raman, EDAX, SEM, EIS, and ESEM equipment, unique in-situ measurement techniques and test benches (Environmental EM, Transient Mass-Spectrometer-MS, and IR Optical Temperature measurements). In addition, computational capabilities have been developed culminating in a multi-scale multi-physics fuel cell simulation code, DREAM-SOFC, as well as a Beowulf cluster with 64 CPU units. We have trained 16 graduate students, 10 postdoctoral fellows, and recruited 4 new young faculty members who have actively participated in the EPSCoR project. All four of these faculty members have already been promoted to the tenured associate professor level. With the help of these faculty and students, we were able to secure 14 research awards/contracts amounting to a total of circa $5.0 Million external funding in closely related areas of research. Using the facilities mentioned above, the effects of PH3, HCl, Cl2, and H2S on cell performance have been studied in detail, mechanisms have been identified, and also remedies have been proposed and demonstrated in the laboratory. For example, it has been determined that PH3 reacts rapidly with Ni to from secondary compounds which may become softer or even melt at high temperature and then induce Ni migration to the surface of the cell changing the material and micro-structural properties of the cell drastically. It is found that

  14. A Preliminary Study of Psychiatric, Familial, and Medical Characteristics of High Utilizing Sickle Cell Disease Patients

    PubMed Central

    Carroll, C. Patrick; Haywood, Carlton; Hoot, Michelle R.; Lanzkron, Sophie

    2012-01-01

    Objectives To identify demographic, medical, and psychosocial characteristics that distinguished sickle cell disease patients who were frequent utilizers of urgent or emergent care resources from low-utilizing patients. Methods Patients at a large urban comprehensive sickle cell disease treatment center were recruited from clinic or during urgent care visits. Participants who were high utilizers, defined as having more than 4 acute or emergency care visits in the prior 12 months, were compared to patients with more typical utilization patterns on lifetime complications of SCD, family background, psychiatric history, occupational function, coping, depressive symptoms, and personality. Results High utilizers were nearly a decade younger on average; despite this they had a similar lifetime history of SCD complications. High utilizing patients' parents appeared to have greater educational achievement overall. High utilizers reported a nearly three-fold greater prevalence of psychiatric illness in family members than low utilizers. On other measures; including coping strategies, social support, and personality; the two groups were comparable. Discussion The study strengthens emerging evidence that disease severity, familial factors related to greater parental education, and psychiatric illness are important factors in high care utilization in patients with sickle cell disease. PMID:23246997

  15. Primary cells utilize halogen-organic charge transfer complex

    NASA Technical Reports Server (NTRS)

    Gutmann, F.; Hermann, A. M.; Rembaum, A.

    1966-01-01

    Electrochemical cells with solid state components employ charge transfer complexes or donor-acceptor complexes in which the donor component is an organic compound and the acceptor component is a halogen. A minor proportion of graphite added to these composition helps reduce the resistivity.

  16. Panel fabrication utilizing GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Mardesich, N.

    1984-01-01

    The development of the GaAs solar cells for space applications is described. The activities in the fabrication of GaAs solar panels are outlined. Panels were fabricated while introducing improved quality control, soldering laydown and testing procedures. These panels include LIPS II, San Marco Satellite, and a low concentration panel for Rockwells' evaluation. The panels and their present status are discussed.

  17. Solar cell utilizing photochemical generation of electricity. Semiannual research report

    SciTech Connect

    Stevenson, K. L.

    1980-01-01

    Research on the design and development of a photogalvanic cell using a transparent electrode of indium oxide-tin oxide coated on plate glass, an electrolytic containing iodine, and an inert electrode is described. Preliminary spectral response and efficiency data are given. (WHK)

  18. Potential benefits and limitations of utilizing chondroprogenitors in cell-based cartilage therapy.

    PubMed

    Jayasuriya, Chathuraka T; Chen, Qian

    2015-01-01

    Chondroprogenitor cells are a subpopulation of multipotent progenitors that are primed for chondrogenesis. They are believed to have the biological repertoire to be ideal for cell-based cartilage therapy. In addition to summarizing recent advances in chondroprogenitor cell characterization, this review discusses the projected pros and cons of utilizing chondroprogenitors in regenerative medicine and compares them with that of pre-existing methods, including autologous chondrocyte implantation (ACI) and the utilization of bone marrow derived mesenchymal stem cells (MSCs) for the purpose of cartilage tissue repair. PMID:26075411

  19. Plasmonic nanocrystal solar cells utilizing strongly confined radiation.

    PubMed

    Kholmicheva, Natalia; Moroz, Pavel; Rijal, Upendra; Bastola, Ebin; Uprety, Prakash; Liyanage, Geethika; Razgoniaev, Anton; Ostrowski, Alexis D; Zamkov, Mikhail

    2014-12-23

    The ability of metal nanoparticles to concentrate light via the plasmon resonance represents a unique opportunity for funneling the solar energy in photovoltaic devices. The absorption enhancement in plasmonic solar cells is predicted to be particularly prominent when the size of metal features falls below 20 nm, causing the strong confinement of radiation modes. Unfortunately, the ultrashort lifetime of such near-field radiation makes harvesting the plasmon energy in small-diameter nanoparticles a challenging task. Here, we develop plasmonic solar cells that harness the near-field emission of 5 nm Au nanoparticles by transferring the plasmon energy to band gap transitions of PbS semiconductor nanocrystals. The interfaces of Au and PbS domains were designed to support a rapid energy transfer at rates that outpace the thermal dephasing of plasmon modes. We demonstrate that central to the device operation is the inorganic passivation of Au nanoparticles with a wide gap semiconductor, which reduces carrier scattering and simultaneously improves the stability of heat-prone plasmonic films. The contribution of the Au near-field emission toward the charge carrier generation was manifested through the observation of an enhanced short circuit current and improved power conversion efficiency of mixed (Au, PbS) solar cells, as measured relative to PbS-only devices. PMID:25403025

  20. Utilizing stem cells for three-dimensional neural tissue engineering.

    PubMed

    Knowlton, Stephanie; Cho, Yongku; Li, Xue-Jun; Khademhosseini, Ali; Tasoglu, Savas

    2016-05-26

    Three-dimensional neural tissue engineering has made great strides in developing neural disease models and replacement tissues for patients. However, the need for biomimetic tissue models and effective patient therapies remains unmet. The recent push to expand 2D neural tissue engineering into the third dimension shows great potential to advance the field. Another area which has much to offer to neural tissue engineering is stem cell research. Stem cells are well known for their self-renewal and differentiation potential and have been shown to give rise to tissues with structural and functional properties mimicking natural organs. Application of these capabilities to 3D neural tissue engineering may be highly useful for basic research on neural tissue structure and function, engineering disease models, designing tissues for drug development, and generating replacement tissues with a patient's genetic makeup. Here, we discuss the vast potential, as well as the current challenges, unique to integration of 3D fabrication strategies and stem cells into neural tissue engineering. We also present some of the most significant recent achievements, including nerve guidance conduits to facilitate better healing of nerve injuries, functional 3D biomimetic neural tissue models, physiologically relevant disease models for research purposes, and rapid and effective screening of potential drugs. PMID:26890524

  1. Clinical Utility of Circulating Tumor Cells in ALK-Positive Non-Small-Cell Lung Cancer

    PubMed Central

    Faugeroux, Vincent; Pailler, Emma; Auger, Nathalie; Taylor, Melissa; Farace, Françoise

    2014-01-01

    The advent of rationally targeted therapies such as small-molecule tyrosine kinase inhibitors (TKIs) has considerably transformed the therapeutic management of a subset of patients with non-small-cell lung cancer (NSCLC) harboring defined molecular abnormalities. When such genetic molecular alterations are detected the use of specific TKI has demonstrated better results (overall response rate, progression free survival) compared to systemic therapy. However, the detection of such molecular abnormalities is complicated by the difficulty in obtaining sufficient tumor material, in terms of quantity and quality, from a biopsy. Here, we described how circulating tumor cells (CTCs) can have a clinical utility in anaplastic lymphoma kinase (ALK) positive NSCLC patients to diagnose ALK-EML4 gene rearrangement and to guide therapeutic management of these patients. The ability to detect genetic abnormalities such ALK rearrangement in CTCs shows that these cells could offer new perspectives both for the diagnosis and the monitoring of ALK-positive patients eligible for treatment with ALK inhibitors. PMID:25414829

  2. Clinical Utility of Circulating Tumor Cells in ALK-Positive Non-Small-Cell Lung Cancer.

    PubMed

    Faugeroux, Vincent; Pailler, Emma; Auger, Nathalie; Taylor, Melissa; Farace, Françoise

    2014-01-01

    The advent of rationally targeted therapies such as small-molecule tyrosine kinase inhibitors (TKIs) has considerably transformed the therapeutic management of a subset of patients with non-small-cell lung cancer (NSCLC) harboring defined molecular abnormalities. When such genetic molecular alterations are detected the use of specific TKI has demonstrated better results (overall response rate, progression free survival) compared to systemic therapy. However, the detection of such molecular abnormalities is complicated by the difficulty in obtaining sufficient tumor material, in terms of quantity and quality, from a biopsy. Here, we described how circulating tumor cells (CTCs) can have a clinical utility in anaplastic lymphoma kinase (ALK) positive NSCLC patients to diagnose ALK-EML4 gene rearrangement and to guide therapeutic management of these patients. The ability to detect genetic abnormalities such ALK rearrangement in CTCs shows that these cells could offer new perspectives both for the diagnosis and the monitoring of ALK-positive patients eligible for treatment with ALK inhibitors. PMID:25414829

  3. Application of fuel cells with heat recovery for integrated utility systems

    NASA Technical Reports Server (NTRS)

    Shields, V.; King, J. M., Jr.

    1975-01-01

    This paper presents the results of a study of fuel cell powerplants with heat recovery for use in an integrated utility system. Such a design provides for a low pollution, noise-free, highly efficient integrated utility. Use of the waste heat from the fuel cell powerplant in an integrated utility system for the village center complex of a new community results in a reduction in resource consumption of 42 percent compared to conventional methods. In addition, the system has the potential of operating on fuels produced from waste materials (pyrolysis and digester gases); this would provide further reduction in energy consumption.

  4. Differential Utilization of Dietary Fatty Acids in Benign and Malignant Cells of the Prostate.

    PubMed

    Dueregger, Andrea; Schöpf, Bernd; Eder, Theresa; Höfer, Julia; Gnaiger, Erich; Aufinger, Astrid; Kenner, Lukas; Perktold, Bernhard; Ramoner, Reinhold; Klocker, Helmut; Eder, Iris E

    2015-01-01

    Tumor cells adapt via metabolic reprogramming to meet elevated energy demands due to continuous proliferation, for example by switching to alternative energy sources. Nutrients such as glucose, fatty acids, ketone bodies and amino acids may be utilized as preferred substrates to fulfill increased energy requirements. In this study we investigated the metabolic characteristics of benign and cancer cells of the prostate with respect to their utilization of medium chain (MCTs) and long chain triglycerides (LCTs) under standard and glucose-starved culture conditions by assessing cell viability, glycolytic activity, mitochondrial respiration, the expression of genes encoding key metabolic enzymes as well as mitochondrial mass and mtDNA content. We report that BE prostate cells (RWPE-1) have a higher competence to utilize fatty acids as energy source than PCa cells (LNCaP, ABL, PC3) as shown not only by increased cell viability upon fatty acid supplementation but also by an increased ß-oxidation of fatty acids, although the base-line respiration was 2-fold higher in prostate cancer cells. Moreover, BE RWPE-1 cells were found to compensate for glucose starvation in the presence of fatty acids. Of notice, these findings were confirmed in vivo by showing that PCa tissue has a lower capacity in oxidizing fatty acids than benign prostate. Collectively, these metabolic differences between benign and prostate cancer cells and especially their differential utilization of fatty acids could be exploited to establish novel diagnostic and therapeutic strategies. PMID:26285134

  5. Differential Utilization of Dietary Fatty Acids in Benign and Malignant Cells of the Prostate

    PubMed Central

    Eder, Theresa; Höfer, Julia; Gnaiger, Erich; Aufinger, Astrid; Kenner, Lukas; Perktold, Bernhard; Ramoner, Reinhold; Klocker, Helmut; Eder, Iris E.

    2015-01-01

    Tumor cells adapt via metabolic reprogramming to meet elevated energy demands due to continuous proliferation, for example by switching to alternative energy sources. Nutrients such as glucose, fatty acids, ketone bodies and amino acids may be utilized as preferred substrates to fulfill increased energy requirements. In this study we investigated the metabolic characteristics of benign and cancer cells of the prostate with respect to their utilization of medium chain (MCTs) and long chain triglycerides (LCTs) under standard and glucose-starved culture conditions by assessing cell viability, glycolytic activity, mitochondrial respiration, the expression of genes encoding key metabolic enzymes as well as mitochondrial mass and mtDNA content. We report that BE prostate cells (RWPE-1) have a higher competence to utilize fatty acids as energy source than PCa cells (LNCaP, ABL, PC3) as shown not only by increased cell viability upon fatty acid supplementation but also by an increased ß-oxidation of fatty acids, although the base-line respiration was 2-fold higher in prostate cancer cells. Moreover, BE RWPE-1 cells were found to compensate for glucose starvation in the presence of fatty acids. Of notice, these findings were confirmed in vivo by showing that PCa tissue has a lower capacity in oxidizing fatty acids than benign prostate. Collectively, these metabolic differences between benign and prostate cancer cells and especially their differential utilization of fatty acids could be exploited to establish novel diagnostic and therapeutic strategies. PMID:26285134

  6. Parametric analysis of lithium oxyhalide spirally wound cells utilizing the Taguchi approach to experimental design

    SciTech Connect

    Takeuchi, E.S.; Size, P.J.

    1994-12-31

    The Taguchi Method of Experimental Design was utilized to parametrically assess the effects of four variables in cell configuration on performance of spirally wound lithium oxyhalide D cells. This approach utilizes fractional factorial designs requiring a fraction of the number of experiments required of full factorial experiments. The Taguchi approach utilizes ANOVA analysis for calculating the percent contribution of each factor to battery performance as well as main effects of each factor. The four factors investigated in this study were the electrolyte type, the electrolyte concentration, the depolarizer type, and the mechanical cell design. The effects of these four factors on 1A constant current discharge, low temperature discharge, start-up, and shelf-life were evaluated. The factor having the most significant effect on cell performance was the electrolyte type.

  7. Utility of Thin-Film Solar Cells on Flexible Substrates for Space Power

    NASA Technical Reports Server (NTRS)

    Dickman, J. E.; Hepp, A. F.; Morel, D. L.; Ferekides, C. S.; Tuttle, J. R.; Hoffman, D. J.; Dhere, N. G.

    2004-01-01

    The thin-film solar cell program at NASA GRC is developing solar cell technologies for space applications which address two critical metrics: specific power (power per unit mass) and launch stowed volume. To be competitive for many space applications, an array using thin film solar cells must significantly increase specific power while reducing stowed volume when compared to the present baseline technology utilizing crystalline solar cells. The NASA GRC program is developing two approaches. Since the vast majority of the mass of a thin film solar cell is in the substrate, a thin film solar cell on a very lightweight flexible substrate (polymer or metal films) is being developed as the first approach. The second approach is the development of multijunction thin film solar cells. Total cell efficiency can be increased by stacking multiple cells having bandgaps tuned to convert the spectrum passing through the upper cells to the lower cells. Once developed, the two approaches will be merged to yield a multijunction, thin film solar cell on a very lightweight, flexible substrate. The ultimate utility of such solar cells in space require the development of monolithic interconnections, lightweight array structures, and ultra-lightweight support and deployment techniques.

  8. L-baclofen-sensitive GABAB binding sites in the medial vestibular nucleus localized by immunocytochemistry

    NASA Technical Reports Server (NTRS)

    Holstein, G. R.; Martinelli, G. P.; Cohen, B.

    1992-01-01

    L-Baclofen-sensitive GABAB binding sites in the medial vestibular nucleus (MVN) were identified immunocytochemically and visualized ultrastructurally in L-baclofen-preinjected rats and monkeys, using a mouse monoclonal antibody with specificity for the p-chlorophenyl moiety of baclofen. Saline-preinjected animals showed no immunostain. In drug-injected animals, there was evidence for both pre- and postsynaptic GABAergic inhibition in MVN mediated by GABAB receptors. These neural elements could be utilized in control of velocity storage in the vestibulo-ocular reflex.

  9. Uptake and utilization of CDP-choline in primary brain cell cultures from fetal brain

    SciTech Connect

    Vecchini, A.; Binaglia, L.; Floridi, A.; Palmerini, C.A.; Procellati, G.

    1983-03-01

    The utilization of double-labeled CDP-choline by cultured brain cells has been studied. CDP-choline is demonstrated to be rapidly hydrolysed into CMP and choline phosphate. The fragments, or their hydrolysis products, penetrate into the cells and are utilized for lipid synthesis. At short times after the isotope administration a rapid labeling of phosphatidylcholine was detected, when cells were incubated with CDP-choline. The same was not seen when cells were incubated with labeled choline. From these observations it can be inferred that either CDP- choline can penetrate the cell membrane or that some mechanism involving CDP-choline and leading to phospholipid synthesis can work at the external surface of the plasma membranes.

  10. Construction of a starch-utilizing yeast by cell surface engineering.

    PubMed Central

    Murai, T; Ueda, M; Yamamura, M; Atomi, H; Shibasaki, Y; Kamasawa, N; Osumi, M; Amachi, T; Tanaka, A

    1997-01-01

    We have engineered the cell surface of the yeast Saccharomyces cerevisiae by anchoring active glucoamylase protein on the cell wall, and we have endowed the yeast cells with the ability to utilize starch directly as the sole carbon source. The gene encoding Rhizopus oryzae glucoamylase with its secretion signal peptide was fused with the gene encoding the C-terminal half (320 amino acid residues from the C terminus) of yeast alpha-agglutinin, a protein involved in mating and covalently anchored to the cell wall. The constructed plasmid containing this fusion gene was introduced into S. cerevisiae and expressed under the control of the glyceraldehyde-3-phosphate dehydrogenase promoter from S. cerevisiae. The glucoamylase activity as not detected in the culture medium, but it was detected in the cell pellet fraction. The glucoamylase protein transferred to the soluble fraction from the cell wall fraction after glucanase treatment but not after sodium dodecyl sulfate treatment, indicating the covalent binding of the fusion protein to the cell wall. Display of the fused protein was further confirmed by immunofluorescence microscopy and immunoelectron microscopy. The transformant cells could surely grow on starch as the sole carbon source. These results showed that the glucoamylase was anchored on the cell wall and displayed as its active form. This is the first example of an application of cell surface engineering to utilize and improve the metabolic ability of cells. PMID:9097432

  11. Effect of Mangiferin and Mahanimbine on Glucose Utilization in 3T3-L1 cells

    PubMed Central

    Kumar, B Dinesh; Krishnakumar, K; Jaganathan, Saravana Kumar; Mandal, Mahitosh

    2013-01-01

    Background: Stem barks of Mangifera indica contain a rich content of mangiferin (xanthone glucoside), whereas Murraya koenigii leaves contain rich sources of mahanimbine (carbazole alkaloid) and used traditionally for the treatment of diabetes. Objective: To investigate the effects of mangiferin (xanthone glucoside) and mahanimbine (carbazole alkaloid) on glucose utilization in 3T3-L1 cells. Materials and Methods: Mangiferin was isolated from stem barks of Mangifera indica and mahanimbine was isolated from Murraya koenigii leaves. These isolated compounds were subjected to MTT assay and glucose utilization test with 3T3-L1 cells. Results: Treatment of the 3T3-L1 cells with mangiferin and mahanimbine increased the glucose utilization in a dose-dependent manner. At a concentration of 1 mM, mangniferin showed 2-fold increase in glucose utilization compared with untreated control. In case of mahanimbine, the observed effect at 1 mM was almost equivalent to positive control (insulin at 1 μM). Moreover, MTT assay showed that both of these compounds were less toxic at a concentration of 1 mM (nearly 75% cells are viable). Conclusion: The present results indicated that these natural products (mangiferin and mahanimbine) exhibited potential ethnomedical uses in management of diabetes. PMID:23661997

  12. Deficit in sustained attention following selective cholinergic lesion of the pedunculopontine tegmental nucleus in rat, as measured with both post-mortem immunocytochemistry and in vivo PET imaging with [¹⁸F]fluoroethoxybenzovesamicol.

    PubMed

    Cyr, Marilyn; Parent, Maxime J; Mechawar, Naguib; Rosa-Neto, Pedro; Soucy, Jean-Paul; Clark, Stewart D; Aghourian, Meghmik; Bedard, Marc-Andre

    2015-02-01

    Cholinergic neurons of the pedunculopontine tegmental nucleus (PPTg) are thought to be involved in cognitive functions such as sustained attention, and lesions of these cells have been documented in patients showing fluctuations of attention such as in Parkinson's disease or dementia with Lewy Body. Animal studies have been conducted to support the role of these cells in attention, but the lesions induced in these animals were not specific to the cholinergic PPTg system, and were assessed by post-mortem methods remotely performed from the in vivo behavioral assessments. Moreover, sustained attention have not been directly assessed in these studies, but rather deduced from indirect measurements. In the present study, rats were assessed on the 5-Choice Serial Reaction Time Task (5-CSRTT), and a specific measure of variability in response latency was created. Animals were observed both before and after selective lesion of the PPTg cholinergic neurons. Brain cholinergic denervation was assessed both in vivo and ex vivo, using PET imaging with [(18)F]fluoroethoxybenzovesamicol ([(18)F]FEOBV) and immunocytochemistry respectively. Results showed that the number of correct responses and variability in response latency in the 5-CSRTT were the only behavioral measures affected following the lesions. These measures were found to correlate significantly with the number of PPTg cholinergic cells, as measured with both [(18)F]FEOBV and immunocytochemistry. This suggests the primary role of the PPTg cholinergic cells in sustained attention. It also allows to reliably use the PET imaging with [(18)F]FEOBV for the purpose of assessing the relationship between behavior and cholinergic innervation in living animals. PMID:25257103

  13. Utilities for High-Throughput Analysis of B-Cell Clonal Lineages

    PubMed Central

    Lees, William D.; Shepherd, Adrian J.

    2015-01-01

    There are at present few tools available to assist with the determination and analysis of B-cell lineage trees from next-generation sequencing data. Here we present two utilities that support automated large-scale analysis and the creation of publication-quality results. The tools are available on the web and are also available for download so that they can be integrated into an automated pipeline. Critically, and in contrast to previously published tools, these utilities can be used with any suitable phylogenetic inference method and with any antibody germline library and hence are species-independent. PMID:26527585

  14. Rapid immunocytochemistry based on alternating current electric field using squash smear preparation of central nervous system tumors.

    PubMed

    Moriya, Jun; Tanino, Mishie Ann; Takenami, Tomoko; Endoh, Tomoko; Urushido, Masana; Kato, Yasutaka; Wang, Lei; Kimura, Taichi; Tsuda, Masumi; Nishihara, Hiroshi; Tanaka, Shinya

    2016-01-01

    The role of intraoperative pathological diagnosis for central nervous system (CNS) tumors is crucial for neurosurgery when determining the surgical procedure. Especially, treatment of carmustine (BCNU) wafers requires a conclusive diagnosis of high-grade glioma proven by intraoperative diagnosis. Recently, we demonstrated the usefulness of rapid immunohistochemistry (R-IHC) that facilitates antigen-antibody reaction under alternative current (AC) electric field in the intraoperative diagnosis of CNS tumors; however, a higher proportion of water and lipid in the brain parenchyma sometimes leads to freezing artifacts, resulting in poor quality of frozen sections. On the other hand, squash smear preparation of CNS tumors for cytology does not affect the frozen artifacts, and the importance of smear preparation is now being re-recognized as being better than that of the tissue sections. In this study, we established the rapid immunocytochemistry (R-ICC) protocol for squash smears of CNS tumors using AC electric field that takes only 22 min, and demonstrated its usefulness for semi-quantitative Ki-67/MIB-1 labeling index and CD 20 by R-ICC for intraoperative diagnosis. R-ICC by AC electric field may become a substantial tool for compensating R-IHC and will be applied for broad antibodies in the future. PMID:26546480

  15. Stem Cell Property of Postmigratory Cranial Neural Crest Cells and Their Utility in Alveolar Bone Regeneration and Tooth Development

    PubMed Central

    Chung, Il-Hyuk; Yamaza, Takayoshi; Zhao, Hu; Choung, Pill-Hoon; Shi, Songtao; Chai, Yang

    2010-01-01

    The vertebrate neural crest is a multipotent cell population that gives rise to a variety of different cell types. We have discovered that postmigratory cranial neural crest cells (CNCCs) maintain mesenchymal stem cell characteristics and show potential utility for the regeneration of craniofacial structures. We are able to induce the osteogenic differentiation of postmigratory CNCCs, and this differentiation is regulated by bone morphogenetic protein (BMP) and transforming growth factor-β signaling pathways. After transplantation into a host animal, postmigratory CNCCs form bone matrix. CNCC-formed bones are distinct from bones regenerated by bone marrow mesenchymal stem cells. In addition, CNCCs support tooth germ survival via BMP signaling in our CNCC-tooth germ cotransplantation system. Thus, we conclude that postmigratory CNCCs preserve stem cell features, contribute to craniofacial bone formation, and play a fundamental role in supporting tooth organ development. These findings reveal a novel function for postmigratory CNCCs in organ development, and demonstrate the utility of these CNCCs in regenerating craniofacial structures. PMID:19350689

  16. Growth factor and small molecule influence on urological tissue regeneration utilizing cell seeded scaffolds.

    PubMed

    Sharma, Arun K; Cheng, Earl Y

    2015-03-01

    Regenerative medicine strategies combine various attributes from multiple disciplines including stem cell biology, chemistry, materials science and medicine. The junction at which these disciplines intersect provides a means to address unmet medical needs in an assortment of pathologies with the goal of creating sustainable, functional replacement tissues. Tissue damage caused by trauma for example, requires rapid responses in order to mitigate further tissue deterioration. Cell/scaffold composites have been utilized to initiate and stabilize regenerative responses in vivo with the hope that functional tissue can be attained. Along with the gross reconfiguration of regenerating tissues, small molecules and growth factors also play a pivotal role in tissue regeneration. Several regenerative studies targeting a variety of urological tissues demonstrate the utility of these small molecules or growth factors in an in vivo setting. PMID:25446138

  17. Effect of Substrate and Cell Surface Hydrophobicity on Phosphate Utilization in Bacteria

    PubMed Central

    Lemke, M. J.; Churchill, P. F.; Wetzel, R. G.

    1995-01-01

    We measured the rates of utilization of hydrophobic and hydrophilic phosphate compounds in gram-negative bacteria with different surface hydrophobicities, isolated from wetland habitats. Three hydrophobic and two hydrophilic bacterial species were selected for study by measuring cell adherence to hydrocarbons. The bacteria were grown under phosphorus-limited conditions with P(infi), hydrophilic (beta)-glycerophosphate, or hydrophobic phosphatidic acid as the phosphate source. Hydrophilic bacteria grew most rapidly on P(infi), followed by (beta)-glycerophosphate. Phosphatidic acid did not support growth or did so at a much later time (40 h) than did the other phosphate treatments. Although all hydrophobic species grew well on these substrates, the rate of growth of two Acinetobacter baumannii isolates on phosphatidic acid exceeded the rate of growth on phosphate or (beta)-glycerophosphate. A membrane phospholipid and lipopolysaccharide were used as a source of phosphorus by hydrophobic species, whereas hydrophilic species could not use the membrane phospholipids and used lipopolysaccharide to a lesser extent. Besides hydrophobic interaction between cells and substrate, phosphatase activity, which was cell bound in hydrophilic species but 30 to 50% unbound in hydrophobic species, affected cell growth. Dialyzed culture supernatant containing phosphatase from hydrophobic species increased the phosphate availability to hydrophilic species. Additionally, cellular extracts from a hydrophilic species, when added to hydrophilic cells, permitted growth on hydrophobic phosphate sources. Naturally occurring amphiphilic humic acids affected the utilization of P(infi) and (beta)-glycerophosphate in bacteria with hydrophilic surfaces but did not affect hydrophobic bacteria. Our results indicate that hydrophobic phosphate sources can be used by bacteria isolated from aquatic environments as the sole phosphorus source for growth. This utilization, in part, appears to be related to

  18. Characteristics of a Nonvolatile SRAM Memory Cell Utilizing a Ferroelectric Transistor

    NASA Technical Reports Server (NTRS)

    Mitchell, Cody; Laws, Crystal; MacLeod, Todd C.; Ho, Fat D.

    2011-01-01

    The SRAM cell circuit is a standard for volatile data storage. When utilizing one or more ferroelectric transistors, the hysteresis characteristics give unique properties to the SRAM circuit, providing for investigation into the development of a nonvolatile memory cell. This paper discusses various formations of the SRAM circuit, using ferroelectric transistors, n-channel and p-channel MOSFETs, and resistive loads. With varied source and supply voltages, the effects on the timing and retention characteristics are investigated, including retention times of up to 24 hours.

  19. Process Developed for Fabricating Engineered Pore Structures for High- Fuel-Utilization Solid Oxide Fuel Cells

    NASA Technical Reports Server (NTRS)

    Sofie, Stephen W.; Cable, Thomas L.; Salamone, Sam M.

    2005-01-01

    Solid oxide fuel cells (SOFCs) have tremendous commercial potential because of their high efficiency, high energy density, and flexible fuel capability (ability to use fossil fuels). The drive for high-power-utilizing, ultrathin electrolytes (less than 10 microns), has placed an increased demand on the anode to provide structural support, yet allow sufficient fuel entry for sustained power generation. Concentration polarization, a condition where the fuel demand exceeds the supply, is evident in all commercial-based anode-supported cells, and it presents a significant roadblock to SOFC commercialization.

  20. Cell compressibility studies utilizing noncontact hydrostatic pressure measurements on single living cells in a microchamber

    NASA Astrophysics Data System (ADS)

    Lin, L. A. G.; Liu, A. Q.; Yu, Y. F.; Zhang, C.; Lim, C. S.; Ng, S. H.; Yap, P. H.; Gao, H. J.

    2008-06-01

    A micro-optical-fluidic system (MOFS), which integrates a force generating device and an optical detector, is designed to measure the bulk modulus of a single living cell in real time under a controlled hydrostatic pressure. In this design, the accuracy of the bulk modulus measurement is improved because neither the force generating device nor the optical detector needs to be in contact with the cells. The MOFS device has been used to investigate the mechanotransduction of THP-1 human acute monocytic leukemia cells and the effects of the toxin lipopolysaccharide and colchicine on various properties of these cells.

  1. Spontaneous calcification process in primary renal cells from a medullary sponge kidney patient harbouring a GDNF mutation

    PubMed Central

    Mezzabotta, Federica; Cristofaro, Rosalba; Ceol, Monica; Del Prete, Dorella; Priante, Giovanna; Familiari, Alessandra; Fabris, Antonia; D'Angelo, Angela; Gambaro, Giovanni; Anglani, Franca

    2015-01-01

    Medullary nephrocalcinosis is a hallmark of medullary sponge kidney (MSK). We had the opportunity to study a spontaneous calcification process in vitro by utilizing the renal cells of a patient with MSK who was heterozygous for the c.-27 + 18G>A variant in the GDNF gene encoding glial cell-derived neurotrophic factor. The cells were obtained by collagenase digestion of papillary tissues from the MSK patient and from two patients who had no MSK or nephrocalcinosis. These cells were typed by immunocytochemistry, and the presence of mineral deposits was studied using von Kossa staining, scanning electron microscopy analysis and an ALP assay. Osteoblastic lineage markers were studied using immunocytochemistry and RT-PCR. Staminality markers were also analysed using flow cytometry, magnetic cell separation technology, immunocytochemistry and RT-PCR. Starting from p2, MSK and control cells formed nodules with a behaviour similar to that of calcifying pericytes; however, Ca2PO4 was only found in the MSK cultures. The MSK cells had morphologies and immunophenotypes resembling those of pericytes or stromal stem cells and were positive for vimentin, ZO1, αSMA and CD146. In addition, the MSK cells expressed osteocalcin and osteonectin, indicating an osteoblast-like phenotype. In contrast to the control cells, GDNF was down-regulated in the MSK cells. Stable GDNF knockdown was established in the HK2 cell line and was found to promote Ca2PO4 deposition when the cells were incubated with calcifying medium by regulating the osteonectin/osteopontin ratio in favour of osteonectin. Our data indicate that the human papilla may be a perivascular niche in which pericyte/stromal-like cells can undergo osteogenic differentiation under particular conditions and suggest that GDNF down-regulation may have influenced the observed phenomenon. PMID:25692823

  2. Cancer immunotherapy utilizing gene-modified T cells: From the bench to the clinic.

    PubMed

    Duong, Connie P M; Yong, Carmen S M; Kershaw, Michael H; Slaney, Clare Y; Darcy, Phillip K

    2015-10-01

    The immune system plays a critical role in the elimination and suppression of pathogens. Although the endogenous immune system is capable of immune surveillance resulting in the elimination of cancer cells, tumor cells have developed a variety of mechanisms to escape immune recognition often resulting in tumor outgrowth. The presence of immune infiltrate in tumors has been correlated with a good prognosis following treatment (Sato et al., 2005; Loi et al., 2013; Clemente et al., 1996; Galon et al., 2006). As such, immune cells such as T cells, have been harnessed in order to target cancer. Tumor reactive lymphocytes, called tumor-infiltrating lymphocytes (TILs) have been isolated and expanded from the tumor and reinfused back into patients for the treatment of melanoma. The promise of adoptive immunotherapy utilizing TILs as a robust treatment for cancer has been highlighted in patients with advanced melanoma with greater than 50% of patients responding to treatment (Dudley et al., 2005). Although TIL therapy has shown promising results in melanoma patients, it has proved difficult to translate this approach to other cancers, given that the numbers of TILs that can be isolated are generally low. To broaden this therapy for other cancers, T cells have been genetically modified to endow them with tumor reactivity using either a T cell receptor (TCR) (Parkhurst et al., 2009, 2011; Chinnasamy et al., 2011) or a chimeric antigen receptor (CAR) (Grupp et al., 2013; Park et al., 2007). This review will outline the origins and development of adoptive immunotherapy utilizing TILs leading to genetic modification strategies to redirect T cells to cancer. Potential hurdles and novel strategies will be discussed for realizing the full potential of adoptive immunotherapy becoming a standard of care treatment for cancer. PMID:25595028

  3. Utilization of site-specific recombination for generating therapeutic protein producing cell lines.

    PubMed

    Campbell, Margie; Corisdeo, Susanne; McGee, Clair; Kraichely, Denny

    2010-07-01

    The AttSite Recombinase Technology from Intrexon, Blacksburg, VA, utilizes specific DNA sequences and proprietary recombinase enzymes to catalyze the insertion of a gene of interest at a specific location in the host cell genome. Using this technology, we have developed Chinese Hamster Ovary (CHO) cell lines that have incorporated attB recombination sites at highly transcriptionally active loci or 'hot spots' within the cell genome. Subsequently, these attB site containing host cell lines could then be used for the expression of future Centocor products. Candidate production cell lines would be generated by a simple recombination event. Since the therapeutic gene of interest would preferentially integrate into the pre-selected high-expressing attB site, candidate cell lines would consistently express high levels of the gene of interest. We have been able to demonstrate that the AttSite Recombinase Technology could be a valid approach for the development of high-expressing production cell lines. PMID:20300883

  4. Single-cell protein production from spent sulfite liquor utilizing cell-recycle and computer monitoring

    SciTech Connect

    Gold, D.; Mohagheghi, A.; Cooney, C.L.; Wang, D.I.C.

    1981-01-01

    To reduce the BOD of spent sulfite liquor before disposal, torula yeast (Candida utilis) is produced by a continuous culture process, the productivity of which is limited by sugar concentration and cell growth rate. To increase productivity, a recycle system has been designed and tested. Cells were sedimented continuously with a flocculating agent (bentonite) before being recycled to the fermentor. A bentonite concentration of 0.02 g/g cell was required. A computer monitoring system based on material balancing techniques was developed to monitor and control the recycle system. With this computer system, productivity was raised to 6.1 g/L-h, with cell concentrations of less than or equal to 65 g/L in the recycle stream and 24 g/L in the fermentor. This represents a productivity increase of 150% over continuous culture with no recycle.

  5. Differential utilization of poly (A) signals between DHFR alleles in CHL cells.

    PubMed Central

    Scotto, K W; Yang, H; Davide, J P; Melera, P W

    1992-01-01

    The Chinese hamster cell line, DC-3F, is heterozygous at the DHFR locus, and each allele can be distinguished on the basis of a unique DNA restriction pattern, protein isoelectric profile and in the abundancy of the DHFR mRNAs it expresses. Although each allele produces four transcripts, 1000, 1650 and 2150 nucleotides [corrected] in length, the relative distribution of these RNAs differs for each; the 2150 nt mRNA represents the major (60%) species generated from one allele, while the 1000 nt mRNA is the major species generated from the other. The allele that predominantly expresses the 2150 nt transcript is preferentially overexpressed when DC-3F cells are subjected to selection in methotrexate. We have analyzed the 3' ends of both DHFR alleles and have found that the three major mRNAs arise by readthrough of multiple polyadenylation signals. A four base deletion in one allele changes the consensus polyadenylation signal AAUAAA to AAUAAU, resulting in the utilization of a cryptic polyadenylation signal lying 21 bp upstream. Surprisingly, this mutation in the third polyadenylation signal appears to affect not only the utilization of this signal, but also the efficiency with which the first signal, located 1171 bp upstream from the third site, is utilized. Images PMID:1480480

  6. Effect of fuel utilization on the carbon monoxide poisoning dynamics of Polymer Electrolyte Membrane Fuel Cells

    NASA Astrophysics Data System (ADS)

    Pérez, Luis C.; Koski, Pauli; Ihonen, Jari; Sousa, José M.; Mendes, Adélio

    2014-07-01

    The effect of fuel utilization on the poisoning dynamics by carbon monoxide (CO) is studied for future automotive conditions of Polymer Electrolyte Membrane Fuel Cells (PEMFC). Three fuel utilizations are used, 70%, 40% and 25%. CO is fed in a constant concentration mode of 1 ppm and in a constant molar flow rate mode (CO concentrations between 0.18 and 0.57 ppm). The concentrations are estimated on a dry gas basis. The CO concentration of the anode exhaust gas is analyzed using gas chromatography. CO is detected in the anode exhaust gas almost immediately after it is added to the inlet gas. Moreover, the CO concentration of the anode exhaust gas increases with the fuel utilization for both CO feed modes. It is demonstrated that the lower the fuel utilization, the higher the molar flow rate of CO at the anode outlet at early stages of the CO poisoning. These results suggest that the effect of CO in PEMFC systems with anode gas recirculation is determined by the dynamics of its accumulation in the recirculation loop. Consequently, accurate quantification of impurities limits in current fuel specification (ISO 14687-2:2012) should be determined using anode gas recirculation.

  7. Characteristics of acute care utilization of a Delaware adult sickle cell disease patient population.

    PubMed

    Anderson, Nina; Bellot, Jennifer; Senu-Oke, Oluseyi; Ballas, Samir K

    2014-02-01

    Sickle cell disease (SCD) is an inherited blood disorder that is chronic in nature and manifests itself through many facets of the patient's life. Comprehensive specialty centers have the potential to reduce health care costs and improve the quality of care for patients who have chronic medical conditions such as heart failure and SCD. The purpose of this practice inquiry was to analyze de-identified data for acute care episodes involving SCD in order to create a detailed picture of acute care utilization for adult patients in Delaware with SCD from 2007 to 2009. Gaining a better understanding of acute care utilization for adults with SCD may provide evidence to improve access to high-quality health care services for this vulnerable patient population in the state of Delaware. PMID:23965046

  8. Subcutaneous Adipose Tissue–Derived Stem Cell Utility Is Independent of Anatomical Harvest Site

    PubMed Central

    Choudhery, Mahmood S.; Badowski, Michael; Muise, Angela; Pierce, John; Harris, David T.

    2015-01-01

    Abstract One of the challenges for tissue engineering and regenerative medicine is to obtain suitably large cell numbers for therapy. Mesenchymal stem cells (MSCs) can easily be expanded in vitro to obtain large numbers of cells, but this approach may induce cellular senescence. The characteristics of cells are dependent on variables like age, body mass index (BMI), and disease conditions, however, and in the case of adipose tissue–derived stem cells (ASCs), anatomical harvest site is also an important variable that can affect the regenerative potential of isolated cells. We therefore had kept the parameters (age, BMI, disease conditions) constant in this study to specifically assess influence of anatomical sites of individual donors on utility of ASCs. Adipose tissue was obtained from multiple anatomical sites in individual donors, and viability and nucleated cell yield were determined. MSC frequency was enumerated using colony forming unit assay and cells were characterized by flow cytometry. Growth characteristics were determined by long-term population doubling analysis of each sample. Finally, MSCs were induced to undergo adipogenic, osteogenic, and chondrogenic differentiation. To validate the findings, these results were compared with similar single harvest sites from multiple individual patients. The results of the current study indicated that MSCs obtained from multiple harvest sites in a single donor have similar morphology and phenotype. All adipose depots in a single donor exhibited similar MSC yield, viability, frequency, and growth characteristics. Equivalent differentiation capacity into osteocytes, adipocytes, and chondrocytes was also observed. On the basis of results, we conclude that it is acceptable to combine MSCs obtained from various anatomical locations in a single donor to obtain suitably large cell numbers required for therapy, avoiding in vitro senescence and lengthy and expensive in vitro culturing and expansion steps. PMID:26309790

  9. Production of Solar Cells in Space from Non Specific Ores by Utilization of Electronically Enhanced Sputtering

    NASA Technical Reports Server (NTRS)

    Curreri, Peter A.

    2009-01-01

    An ideal method of construction in space would utilize some form of the Universal Differentiator and Universal Constructor as described by Von Neumann (1). The Universal Differentiator is an idealized non ore specific extractive device which is capable of breaking any ore into its constituent elements, and the Universal Constructor can utilize these elements to build any device with controllability to the nanometer scale. During the Human Exploration Initiative program in the early 1990s a conceptual study was done (2) to understand whether such devices were feasible with near term technology for the utilization of space resources and energy. A candidate system was proposed which would utilize electronically enhanced sputtering as the differentiator. Highly ionized ions would be accelerated to a kinetic energy at which the interaction between them and the lattice elections in the ore would be at a maximum. Experiments have shown that the maximum disintegration of raw material occurs at an ion kinetic energy of about 5 MeV, regardless of the composition and structure of the raw material. Devices that could produce charged ion beams in this energy range in space were being tested in the early 1990s. At this energy, for example an ion in a beam of fluorine ions yields about 8 uranium ions from uranium fluoride, 1,400 hydrogen and oxygen atoms from ice, or 7,000 atoms from sulfur dioxide ice. The ions from the disintegrated ore would then be driven by an electrical field into a discriminator in the form of a mass spectrometer, where the magnetic field would divert the ions into collectors for future use or used directly in molecular beam construction techniques. The process would require 10-7 Torr vacuum which would be available in space or on the moon. If the process were used to make thin film silicon solar cells (ignoring any energy inefficiency for beam production), then energy break even for solar cells in space would occur after 14 days.

  10. Oncogenic Herpesvirus Utilizes Stress-Induced Cell Cycle Checkpoints for Efficient Lytic Replication

    PubMed Central

    Turunen, Mikko; Diaz, Raquel; Lyly, Lauri; Pekkonen, Pirita; Rantala, Juha; Ojala, Krista; Sarek, Grzegorz; Teesalu, Mari; Denisova, Oxana; Peltonen, Karita; Julkunen, Ilkka; Varjosalo, Markku; Kainov, Denis; Kallioniemi, Olli; Laiho, Marikki; Taipale, Jussi; Hautaniemi, Sampsa; Ojala, Päivi M.

    2016-01-01

    Kaposi’s sarcoma herpesvirus (KSHV) causes Kaposi’s sarcoma and certain lymphoproliferative malignancies. Latent infection is established in the majority of tumor cells, whereas lytic replication is reactivated in a small fraction of cells, which is important for both virus spread and disease progression. A siRNA screen for novel regulators of KSHV reactivation identified the E3 ubiquitin ligase MDM2 as a negative regulator of viral reactivation. Depletion of MDM2, a repressor of p53, favored efficient activation of the viral lytic transcription program and viral reactivation. During lytic replication cells activated a p53 response, accumulated DNA damage and arrested at G2-phase. Depletion of p21, a p53 target gene, restored cell cycle progression and thereby impaired the virus reactivation cascade delaying the onset of virus replication induced cytopathic effect. Herpesviruses are known to reactivate in response to different kinds of stress, and our study now highlights the molecular events in the stressed host cell that KSHV has evolved to utilize to ensure efficient viral lytic replication. PMID:26891221

  11. Prognostic Utility of Routine Chimerism Testing at 2 – 6 Months after Allogeneic Hematopoietic Cell Transplantation

    PubMed Central

    Mossallam, Ghada I.; Kamel, Azza M.; Storer, Barry; Martin, Paul J.

    2009-01-01

    The utility of routine chimerism analysis as a prognostic indicator of subsequent outcomes after allogeneic hematopoietic cell transplantation (HCT) with myeloablative conditioning regimens remains controversial. To address this controversy, routine chimerism test results at 2 – 6 months after HCT with myeloablative conditioning regimens were evaluated for association with subsequent risks of chronic graft versus host disease (GVHD), non-relapse mortality (NRM), relapse and overall mortality. Only 70 (5%) of 1304 patients had <95% donor-derived cells in the marrow. Low donor chimerism in the marrow occurred predominantly among patients with low risk disease as compared to higher risk diseases and was significantly associated with a reduced risk of chronic GVHD. Among 673 patients tested, 164 (24%) had <85% donor-derived T cells in the blood. Low donor T cell chimerism occurred predominantly among patients with low risk disease as compared to higher risk diseases, among those who had conditioning with busulfan as compared to TBI, and among those with lower grades of acute GVHD. Low donor T cell chimerism in the blood was significantly associated with a reduced risk of chronic GVHD, but not with the risks of relapse, NRM or overall mortality. Routine testing of chimerism in the marrow and blood at 2 – 6 months after HCT with myeloablative conditioning regimens may be helpful in documenting engraftment in clinical trials but provides only limited prognostic information in clinical practice. PMID:19203726

  12. Oncogenic Herpesvirus Utilizes Stress-Induced Cell Cycle Checkpoints for Efficient Lytic Replication.

    PubMed

    Balistreri, Giuseppe; Viiliäinen, Johanna; Turunen, Mikko; Diaz, Raquel; Lyly, Lauri; Pekkonen, Pirita; Rantala, Juha; Ojala, Krista; Sarek, Grzegorz; Teesalu, Mari; Denisova, Oxana; Peltonen, Karita; Julkunen, Ilkka; Varjosalo, Markku; Kainov, Denis; Kallioniemi, Olli; Laiho, Marikki; Taipale, Jussi; Hautaniemi, Sampsa; Ojala, Päivi M

    2016-02-01

    Kaposi's sarcoma herpesvirus (KSHV) causes Kaposi's sarcoma and certain lymphoproliferative malignancies. Latent infection is established in the majority of tumor cells, whereas lytic replication is reactivated in a small fraction of cells, which is important for both virus spread and disease progression. A siRNA screen for novel regulators of KSHV reactivation identified the E3 ubiquitin ligase MDM2 as a negative regulator of viral reactivation. Depletion of MDM2, a repressor of p53, favored efficient activation of the viral lytic transcription program and viral reactivation. During lytic replication cells activated a p53 response, accumulated DNA damage and arrested at G2-phase. Depletion of p21, a p53 target gene, restored cell cycle progression and thereby impaired the virus reactivation cascade delaying the onset of virus replication induced cytopathic effect. Herpesviruses are known to reactivate in response to different kinds of stress, and our study now highlights the molecular events in the stressed host cell that KSHV has evolved to utilize to ensure efficient viral lytic replication. PMID:26891221

  13. Laminar flow-based micro fuel cell utilizing grooved electrode surface

    NASA Astrophysics Data System (ADS)

    Ha, Seung-Mo; Ahn, Yoomin

    2014-12-01

    Microfluidic fuel cells have low power density and poor fuel utilization due to the generation of a reaction depletion zone. In this study, cell electrodes patterned with grooves are proposed for passive control of the depletion zone, where a secondary transport flow over the grooved electrode replenishes the depleted layers. The proposed membrane-less fuel cell is composed of a polydimethylsiloxane layer over a photoresist microchannel wall and a glass substrate that contains platinum electrodes. The optimum gap between the electrodes and the height of grooves are designed based on a computational fluid dynamics simulation. Hydrogen peroxide is used both as a fuel (when it is mixed with sodium hydroxide) and as an oxidant (when it is mixed with sulfuric acid). During the experiments, electrodes of various lengths are integrated on the bottom of the Y-channel. Experimental results show that the effect of grooves on cell performance is independent of fuel rate and fuel concentration, but the effect is remarkable when the length of the electrode is large. The peak power density with grooved electrodes improves by a maximum of 13.93% compared to that of planar electrodes. This grooved electrode-based fuel cell is expected to be a useful microdevice for power generation.

  14. Utility of poly(ethylene glycol) based hydrogels for improved neural cell culture and cell delivery systems

    NASA Astrophysics Data System (ADS)

    Namba, Rachael

    Cell transplant therapy is a very promising treatment for patients afflicted with neurodegenerative diseases and involves replacing dying neurons with fresh fetal tissue that is composed of both new neurons and multipotent neural precursor cells (NPCs). Unfortunately, this therapy is not clinically feasible given the scarcity of fresh donor fetal tissue. The NPCs present in fetal tissue may be a promising renewable cell source because they can be instructed to divide indefinitely in culture, expanding the number of NPCs that are available. Importantly, NPCs can also be instructed to differentiate into the therapeutic neurons needed to treat patients. However, when NPCs are expanded in culture, they increasingly differentiate into glial cells. Glial cell contamination not only introduces many uncharacterized signals into NSC cultures, but when transplanted into the brain, glia can contribute to inflammation and glial scarring. The goal of this project is to identify in vitro culture conditions that can be used to expand fresh NPCs while completely avoiding glial differentiation, only allowing the generation of neuronal progeny with therapeutic potential. The culture system used in this work was chosen carefully, and after exploring the utility of standard neural cell culture systems such as monolayer, neurosphere, and three-dimensional fibrin matrices, an advantageous culture system was identified. The chosen culture system is a synthetic, degradable, photo-polymerizable, poly (ethylene) glycocl (PEG) hydrogel. This thesis experimentally demonstrates advantages of PEG hydrogel culture over the other culture systems including enrichment of the initial cell population for NPCs, clonal expansion capabilities, increased potency of proliferation-stimulating mitogens, decreased reactivity and growth of glial cells, and control over the initiation and orientation of neural process growth. PEG hydrogels were used to directly assess the influence of various ECM proteins and

  15. Electrodes and electrochemical storage cells utilizing tin-modified active materials

    DOEpatents

    Anani, Anaba; Johnson, John; Lim, Hong S.; Reilly, James; Schwarz, Ricardo; Srinivasan, Supramaniam

    1995-01-01

    An electrode has a substrate and a finely divided active material on the substrate. The active material is ANi.sub.x-y-z Co.sub.y Sn.sub.z, wherein A is a mischmetal or La.sub.1-w M.sub.w, M is Ce, Nd, or Zr, w is from about 0.05 to about 1.0, x is from about 4.5 to about 5.5, y is from 0 to about 3.0, and z is from about 0.05 to about 0.5. An electrochemical storage cell utilizes such an electrode as the anode. The storage cell further has a cathode, a separator between the cathode and the anode, and an electrolyte.

  16. Bioelectrocatalysts: engineered oxidoreductase system for utilization of fumarate reductase in chemical synthesis, detection, and fuel cells.

    PubMed

    Park, Doo Hyun; Vieille, C; Zeikus, J G

    2003-10-01

    Fumarate reductase was used as a model oxidoreductase to demonstrate continuous electrical cofactor reduction-oxidation during the bioelectrochemical synthesis and detection of chemicals. The enzyme preparation was immobilized onto a graphite felt electrode that was modified with carboxymethylcellulose (CMC). Nicotinamide adenine dinucleotide (NAD), neutral red, and fumarate reductase (which contained menaquinone) were covalently linked by peptide bonds to the CMC. The electron mediator neutral red allowed NAD and menaquinone to be recycled electrically during enzymatic chemical synthesis. Succinate detection by the bioelectrocatalyst was linear from 5 microM to 10 mM succinate. Fumarate synthesis using this bioelectrode was dependent on succinate utilization and resulted in proportional production of electricity and fumarate. Succinate synthesis using this bioelectrocatalyst was dependent on current and fumarate concentration. This bioelectrocatalyst system may enhance the utility of menaquinone- and/or pyridine nucleotide-linked oxidoreductases in diverse enzymatic fuel cells and sensors. It may also enhance the utility of oxidoreductase-based chemical synthesis systems because it eliminates the problem of cofactor recycling. PMID:14566068

  17. Making the grid the backup: Utility applications for fuel cell power

    SciTech Connect

    Eklof, S.L.

    1996-12-31

    Fuel cells are recognized as a versatile power generation option and accepted component of SMUD`s ART Program. SMUD has received wide support and recognition for promoting and implementing fuel cell power plants, as well as other innovative generation, based primarily on technological factors. Current economic and technical realities in the electric generation market highlight other important factors, such as the cost involved to develop a slate of such resources. The goal now is to develop only those select quality resources most likely to become commercially viable in the near future. The challenge becomes the identification of candidate technologies with the greatest potential, and then matching the technologies with the applications that will help to make them successful. Utility participation in this development is critical so as to provide the industry with case examples of advanced technologies that can be applied in a way beneficial to both the utility and its customers. The ART resource acquisitions provide the experience base upon which to guide this selection process, and should bring about the cost reductions and reliability improvements sought.

  18. Enhanced charge collection in dye-sensitized solar cells utilizing collector-shell electrodes

    NASA Astrophysics Data System (ADS)

    Xiao, Manda; Huang, Fuzhi; Xiang, Wanchun; Cheng, Yi-Bing; Spiccia, Leone

    2015-03-01

    Nanostructured porous tin-doped indium oxide (ITO) films were prepared by screen printing of an ITO nanoparticle paste onto conducting fluorine-doped tin oxide (FTO) substrates. The ITO films were subsequently coated with thin layers of TiO2 by the hydrolysis of TiCl4 to form the collector-shell photoelectrodes. The morphology of films was analysed by scanning electron microscope (SEM). It was found that a uniform coating of TiO2 was achieved when three or more deposition cycles were applied. Dye-sensitized solar cells were constructed with the collector-shell photoelectrodes using an electrolyte containing the [Co(bpy)3]2+/3+ (bpy = 2,2‧-bipyridine) redox couple and MK-2, an organic sensitizer and efficiencies of 3.3% achieved. Charge transport in cells utilizing the collector-shell electrodes was found to be 2-6 times faster than those utilizing P25-based TiO2 electrodes.

  19. Ceruloplasmin copper induces oxidant damage by a redox process utilizing cell-derived superoxide as reductant

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, C. K.; Fox, P. L.

    1998-01-01

    Oxidative damage by transition metals bound to proteins may be an important pathogenic mechanism. Ceruloplasmin (Cp) is a Cu-containing plasma protein thought to be involved in oxidative modification of lipoproteins. We have previously shown that Cp increased cell-mediated low-density lipoprotein (LDL) oxidation by a process requiring cell-derived superoxide, but the underlying chemical mechanism(s) is (are) unknown. We now show that superoxide reduction of Cp Cu is a critical reaction in cellular LDL oxidation. By bathocuproine disulfonate (BCS) binding and by superoxide utilization, we showed that exogenous superoxide reduces a single Cp Cu atom, the same Cu required for LDL oxidation. The Cu atom remained bound to Cp during the redox cycle. Three avenues of evidence showed that vascular cells reduce Cp Cu by a superoxide-dependent process. The 2-fold higher rate of Cp Cu reduction by smooth muscle cells (SMC) compared to endothelial cells (EC) was consistent with their relative rates of superoxide release. Furthermore, Cp Cu reduction by cells was blocked by Cu,Zn superoxide dismutase (SOD1). Finally, the level of superoxide produced by EC and SMC was sufficient to cause the amount of Cu reduction observed. An important role of Cp Cu reduction in LDL oxidation was suggested by results showing that SOD1 inhibited Cp Cu reduction and LDL oxidation by SMC with equal potency, while tumor necrosis factor-alpha stimulated both processes. In summary, these results show that superoxide is a critical cellular reductant of divalent transition metals involved in oxidation, and that protein-bound Cu is a substrate for this reaction. The role of these mechanisms in oxidative processes in vivo has yet to be defined.

  20. Developing RCM Strategy for Hydrogen Fuel Cells Utilizing On Line E-Condition Monitoring

    NASA Astrophysics Data System (ADS)

    Baglee, D.; Knowles, M. J.

    2012-05-01

    Fuel cell vehicles are considered to be a viable solution to problems such as carbon emissions and fuel shortages for road transport. Proton Exchange Membrane (PEM) Fuel Cells are mainly used in this purpose because they can run at low temperatures and have a simple structure. Yet high maintenance costs and the inherent dangers of maintaining equipment using hydrogen are two main issues which need to be addressed. The development of appropriate and efficient strategies is currently lacking with regard to fuel cell maintenance. A Reliability Centered Maintenance (RCM) approach offers considerable benefit to the management of fuel cell maintenance since it includes an identification and consideration of the impact of critical components. Technological developments in e-maintenance systems, radio-frequency identification (RFID) and personal digital assistants (PDAs) have proven to satisfy the increasing demand for improved reliability, efficiency and safety. RFID technology is used to store and remotely retrieve electronic maintenance data in order to provide instant access to up-to-date, accurate and detailed information. The aim is to support fuel cell maintenance decisions by developing and applying a blend of leading-edge communications and sensor technology including RFID. The purpose of this paper is to review and present the state of the art in fuel cell condition monitoring and maintenance utilizing RCM and RFID technologies. Using an RCM analysis critical components and fault modes are identified. RFID tags are used to store the critical information, possible faults and their cause and effect. The relationship between causes, faults, symptoms and long term implications of fault conditions are summarized. Finally conclusions are drawn regarding suggested maintenance strategies and the optimal structure for an integrated, cost effective condition monitoring and maintenance management system.

  1. Quantification of cell viability and rapid screening anti-cancer drug utilizing nanomechanical fluctuation.

    PubMed

    Wu, Shangquan; Liu, Xiaoli; Zhou, Xiarong; Liang, Xin M; Gao, Dayong; Liu, Hong; Zhao, Gang; Zhang, Qingchuan; Wu, Xiaoping

    2016-03-15

    Cancer is a serious threat to human health. Although numerous anti-cancer drugs are available clinically, many have shown toxic side effects due to poor tumor-selectivity, and reduced effectiveness due to cancers rapid development of resistance to treatment. The development of new highly efficient and practical methods to quantify cell viability and its change under drug treatment is thus of significant importance in both understanding of anti-cancer mechanism and anti-cancer drug screening. Here, we present an approach of utilizing a nanomechanical fluctuation based highly sensitive microcantilever sensor, which is capable of characterizing the viability of cells and quantitatively screening (within tens of minutes) their responses to a drug with the obvious advantages of a rapid, label-free, quantitative, noninvasive, real-time and in-situ assay. The microcantilever sensor operated in fluctuation mode was used in evaluating the paclitaxel effectiveness on breast cancer cell line MCF-7. This study demonstrated that the nanomechanical fluctuations of the microcantilever sensor are sensitive enough to detect the dynamic variation in cellular force which is provided by the cytoskeleton, using cell metabolism as its energy source, and the dynamic instability of microtubules plays an important role in the generation of the force. We propose that cell viability consists of two parts: biological viability and mechanical viability. Our experimental results suggest that paclitaxel has little effect on biological viability, but has a significant effect on mechanical viability. This new method provides a new concept and strategy for the evaluation of cell viability and the screening of anti-cancer drugs. PMID:26406457

  2. Clinical utility of circulating tumor cell counting through CellSearch®: the dilemma of a concept suspended in Limbo

    PubMed Central

    Raimondi, Cristina; Gradilone, Angela; Naso, Giuseppe; Cortesi, Enrico; Gazzaniga, Paola

    2014-01-01

    To date, 10 years after the first demonstration of circulating tumor cells (CTCs), prognostic significance in metastatic breast cancer using the US Food and Drug Administration–cleared system CellSearch®, the potential utility of CTCs in early clinical development of drugs, their role as a surrogate marker of response to therapy, and their molecular analysis for patient stratification for targeted therapies are still major unsolved questions. Great expectations are pinned on the ongoing interventional trials aimed to demonstrate that CTCs might be of value for guiding treatment of patients and predicting cancer progression. To fill the gap between theory and practice with regard to the clinical utility of CTCs, a bridge is needed, taking into account innovative design for clinical trials, a revised definition of traditional CTCs, next-generation CTC technology, the potential clinical application of CTC analysis in non-validated settings of disease, and finally, expanding the number of patients enrolled in the studies. In this regard, the results of the first European pooled analysis definitely validated the independent prognostic value of CTC counting in metastatic breast cancer patients. PMID:24790460

  3. Optical Frequency Optimization of a High Intensity Laser Power Beaming System Utilizing VMJ Photovoltaic Cells

    NASA Technical Reports Server (NTRS)

    Raible, Daniel E.; Dinca, Dragos; Nayfeh, Taysir H.

    2012-01-01

    An effective form of wireless power transmission (WPT) has been developed to enable extended mission durations, increased coverage and added capabilities for both space and terrestrial applications that may benefit from optically delivered electrical energy. The high intensity laser power beaming (HILPB) system enables long range optical 'refueling" of electric platforms such as micro unmanned aerial vehicles (MUAV), airships, robotic exploration missions and spacecraft platforms. To further advance the HILPB technology, the focus of this investigation is to determine the optimal laser wavelength to be used with the HILPB receiver, which utilizes vertical multi-junction (VMJ) photovoltaic cells. Frequency optimization of the laser system is necessary in order to maximize the conversion efficiency at continuous high intensities, and thus increase the delivered power density of the HILPB system. Initial spectral characterizations of the device performed at the NASA Glenn Research Center (GRC) indicate the approximate range of peak optical-to-electrical conversion efficiencies, but these data sets represent transient conditions under lower levels of illumination. Extending these results to high levels of steady state illumination, with attention given to the compatibility of available commercial off-the-shelf semiconductor laser sources and atmospheric transmission constraints is the primary focus of this paper. Experimental hardware results utilizing high power continuous wave (CW) semiconductor lasers at four different operational frequencies near the indicated band gap of the photovoltaic VMJ cells are presented and discussed. In addition, the highest receiver power density achieved to date is demonstrated using a single photovoltaic VMJ cell, which provided an exceptionally high electrical output of 13.6 W/sq cm at an optical-to-electrical conversion efficiency of 24 percent. These results are very promising and scalable, as a potential 1.0 sq m HILPB receiver of

  4. Recombinant Adeno-Associated Virus Utilizes Cell-Specific Infectious Entry Mechanisms

    PubMed Central

    Weinberg, Marc S.; Nicolson, Sarah; Bhatt, Aadra P.; McLendon, Michael; Li, Chengwen

    2014-01-01

    ABSTRACT Understanding the entry and trafficking mechanism(s) of recombinant adeno-associated virus (rAAV) into host cells can lead to evolution in capsid and vector design and delivery methods, resulting in enhanced transduction and therapeutic gene expression. Variability of findings regarding the early entry pathway of rAAV supports the possibility that rAAV, like other viruses, can utilize more than one infectious entry pathway. We tested whether inhibition of macropinocytosis impacted rAAV transduction of HeLa cells compared to hepatocellular carcinoma cell lines. We found that macropinocytosis inhibitor cytochalasin D blocked rAAV transduction of HeLa cells (>2-fold) but enhanced (10-fold) transduction in HepG2 and Huh7 lines. Similar results were obtained with another macropinocytosis inhibitor, 5-(N-ethyl-N-isopropyl) amiloride (EIPA). The augmented transduction was due to neither viral binding nor promoter activity, affected multiple rAAV serotypes (rAAV2, rAAV2-R585E, and rAAV8), and influenced single-stranded and self-complementary virions to comparable extents. Follow-up studies using CDC42 inhibitor ML141 and p21-activated kinase 1 (PAK1) siRNA knockdown also resulted in enhanced HepG2 transduction. Microscopy revealed that macropinocytosis inhibition correlated with expedited nuclear entry of the rAAV virions into HepG2 cells. Enhancement of hepatocellular rAAV transduction extended to the mouse liver in vivo (4-fold enhancement) but inversely blocked heart tissue transduction (13-fold). This evidence of host cell-specific rAAV entry pathways confers a potent means for controlling and enhancing vector delivery and could help unify the divergent accounts of rAAV cellular entry mechanisms. IMPORTANCE There is a recognized need for improved rAAV vector targeting strategies that result in delivery of fewer total particles, averting untoward toxicity and/or an immune response against the vector. A critical step in rAAV transduction is entry and early

  5. Utility of Lymphoblastoid Cell Lines for Induced Pluripotent Stem Cell Generation

    PubMed Central

    Kumar, Satish; Curran, Joanne E.; Glahn, David C.; Blangero, John

    2016-01-01

    A large number of EBV immortalized LCLs have been generated and maintained in genetic/epidemiological studies as a perpetual source of DNA and as a surrogate in vitro cell model. Recent successes in reprograming LCLs into iPSCs have paved the way for generating more relevant in vitro disease models using this existing bioresource. However, the overall reprogramming efficiency and success rate remain poor and very little is known about the mechanistic changes that take place at the transcriptome and cellular functional level during LCL-to-iPSC reprogramming. Here, we report a new optimized LCL-to-iPSC reprogramming protocol using episomal plasmids encoding pluripotency transcription factors and mouse p53DD (p53 carboxy-terminal dominant-negative fragment) and commercially available reprogramming media. We achieved a consistently high reprogramming efficiency and 100% success rate using this optimized protocol. Further, we investigated the transcriptional changes in mRNA and miRNA levels, using FC-abs ≥ 2.0 and FDR ≤ 0.05 cutoffs; 5,228 mRNAs and 77 miRNAs were differentially expressed during LCL-to-iPSC reprogramming. The functional enrichment analysis of the upregulated genes and activation of human pluripotency pathways in the reprogrammed iPSCs showed that the generated iPSCs possess transcriptional and functional profiles very similar to those of human ESCs. PMID:27375745

  6. Hydrogen Storage in Diamond Powder Utilizing Plasma NaF Surface Treatment for Fuel Cell Applications

    SciTech Connect

    Leal, David A.; Leal-Quiros, E.; Velez, Angel; Prelas, Mark A.; Gosh, Tushar

    2006-12-04

    Hydrogen Fuel Cells offer the vital solution to the world's socio-political dependence on oil. Due to existing difficulty in safe and efficient hydrogen storage for fuel cells, storing the hydrogen in hydrocarbon compounds such as artificial diamond is a realistic solution. By treating the surface of the diamond powder with a Sodium Fluoride plasma exposure, the surface of the diamond is cleaned of unwanted molecules. Due to fluorine's electro negativity, the diamond powder is activated and ready for hydrogen absorption. These diamond powder pellets are then placed on a graphite platform that is heated by conduction in a high voltage circuit made of tungsten wire. Then, the injection of hydrogen gas into chamber allows the storage of the Hydrogen on the surface of the diamond powder. By neutron bombardment in the nuclear reactor, or Prompt Gamma Neutron Activation Analysis, the samples are examined for parts per million amounts of hydrogen in the sample. Sodium Fluoride surface treatment allows for higher mass percentage of stored hydrogen in a reliable, resistant structure, such as diamond for fuel cells and permanently alters the diamonds terminal bonds for re-use in the effective storage of hydrogen. The highest stored amount utilizing the NaF plasma surface treatment was 22229 parts per million of hydrogen in the diamond powder which amounts to 2.2229% mass increase.

  7. Microalgae cultivation in a tubular bioreactor and utilization of their cells

    NASA Astrophysics Data System (ADS)

    Koyu, Hon-Nami; Shunji, Kunito

    1998-03-01

    In this study on the possiblities of microalgae technology as an option for CO2 mitigation, many microalgae were isolated from seawater. Some species of the isolates, Chlamydomonas sp. strain YA-SH-1, which accumulates starch in cells under light and ferment ethanol in dark and anaerobic condition, was grown outdoors by using 50-L tubular bioreactors in batch cultivation and harvested. Using these cells, the performance of ethanol production was examined quantitatively in a 0.5-L scale fermentor. Another species, Tetraselmis sp. strain Tt-1, was cultivated in a semi-batch manner by a similar type of tubular bioreactor indoors and examined for its utilization. Tests showed these cells could be used as partial substitute for wood and kenaf pulp for processing into paper. With the idea of making microalgae produce cellulose by genetic engineering in their minds, the authors studied the structure of bacterial cellulose synthase genes and the low temperature-induced, reversible flocculation in a thermophilic blue green alga (Cyanobacterium), Synechocystis vulcanus in order to examine the feasibility of using these genes as gene source and the cynanobacterium as host.

  8. Using circulating tumor cells to inform on prostate cancer biology and clinical utility

    PubMed Central

    Li, Jing; Gregory, Simon G.; Garcia-Blanco, Mariano A.; Armstrong, Andrew J.

    2016-01-01

    Substantial advances in the molecular biology of prostate cancer have led to the approval of multiple new systemic agents to treat men with metastatic castration-resistant prostate cancer (mCRPC). These treatments encompass androgen receptor directed therapies, immunotherapies, bone targeting radiopharmaceuticals and cytotoxic chemotherapies. There is, however, great heterogeneity in the degree of patient benefit with these agents, thus fueling the need to develop predictive biomarkers that are able to rationally guide therapy. Circulating tumor cells (CTCs) have the potential to provide an assessment of tumor-specific biomarkers through a non-invasive, repeatable “liquid biopsy” of a patient’s cancer at a given point in time. CTCs have been extensively studied in men with mCRPC, where CTC enumeration using the Cellsearch® method has been validated and FDA approved to be used in conjunction with other clinical parameters as a prognostic biomarker in metastatic prostate cancer. In addition to enumeration, more sophisticated molecular profiling of CTCs is now feasible and may provide more clinical utility as it may reflect tumor evolution within an individual particularly under the pressure of systemic therapies. Here, we review technologies used to detect and characterize CTCs, and the potential biological and clinical utility of CTC molecular profiling in men with metastatic prostate cancer. PMID:26079252

  9. Assessment of soft tissue hemangiomas in children utilizing Tc-99m labelled red blood cells

    SciTech Connect

    Miller, J.H.

    1984-01-01

    Hemangiomas may present in infancy as soft tissue masses. Occasionally these lesions may be extensive or may not be clinically recognized as a hemangioma, often causing concern for the presence of a malignant lesion. In later childhood these lesions, which may be occult, may cause overgrowth of an extremity. Evaluation of soft tissue masses suspected of being a hemangioma utilizing Technetium 99m labelled red blood cells has been very valuable. This method allows a dynamic evaluation of first pass blood flow. Subsequent static scintiphotos allow an assessment of the lesion itself. These scintiphotos may be obtained sequentially to evaluate therapy. Twenty patients were evaluated by this method ranging in age from two months to eleven years. There were 13 females and seven males. Lesions evaluated by this method include six hemangiomas of the head and neck: parotic region (2), facial (3), and tongue (1). Extremity lesions were evaluated in six children including both upper extremity (1) and lower extremity (5). Torso lesions evaluated include chest wall (2), abdominal wall (2), and one hemangioma of the gut. This procedure is quickly performed on an outpatient basis, has high anatomic resolution, provides and assessment of these lesions in a manner not available by any other imaging procedure and usually requires no sedation. The radiation exposure for this procedure is low (approximately, a 400mR total body dose) and has been well tolerated by both patients and their parents. Scintigraphic evaluation should be the first diagnostic method utilized in the evaluation of these lesions.

  10. Harvest and utilization of chemical energy in wastes by microbial fuel cells.

    PubMed

    Sun, Min; Zhai, Lin-Feng; Li, Wen-Wei; Yu, Han-Qing

    2016-05-21

    Organic wastes are now increasingly viewed as a resource of energy that can be harvested by suitable biotechnologies. One promising technology is microbial fuel cells (MFC), which can generate electricity from the degradation of organic pollutants. While the environmental benefits of MFC in waste treatment have been recognized, their potential as an energy producer is not fully understood. Although progresses in material and engineering have greatly improved the power output from MFC, how to efficiently utilize the MFC's energy in real-world scenario remains a challenge. In this review, fundamental understandings on the energy-generating capacity of MFC from real waste treatment are provided and the challenges and opportunities are discussed. The limiting factors restricting the energy output and impairing the long-term reliability of MFC are also analyzed. Several energy storage and in situ utilization strategies for the management of MFC's energy are proposed, and future research needs for real-world application of this approach are explored. PMID:26936021

  11. Do Circulating Tumor Cells, Exosomes, and Circulating Tumor Nucleic Acids Have Clinical Utility?

    PubMed Central

    Gold, Bert; Cankovic, Milena; Furtado, Larissa V.; Meier, Frederick; Gocke, Christopher D.

    2016-01-01

    Diagnosing and screening for tumors through noninvasive means represent an important paradigm shift in precision medicine. In contrast to tissue biopsy, detection of circulating tumor cells (CTCs) and circulating tumor nucleic acids provides a minimally invasive method for predictive and prognostic marker detection. This allows early and serial assessment of metastatic disease, including follow-up during remission, characterization of treatment effects, and clonal evolution. Isolation and characterization of CTCs and circulating tumor DNA (ctDNA) are likely to improve cancer diagnosis, treatment, and minimal residual disease monitoring. However, more trials are required to validate the clinical utility of precise molecular markers for a variety of tumor types. This review focuses on the clinical utility of CTCs and ctDNA testing in patients with solid tumors, including somatic and epigenetic alterations that can be detected. A comparison of methods used to isolate and detect CTCs and some of the intricacies of the characterization of the ctDNA are also provided. PMID:25908243

  12. Utilization of hydrolysate from lignocellulosic biomass pretreatment to generate electricity by enzymatic fuel cell system.

    PubMed

    Kim, Sung Bong; Kim, Dong Sup; Yang, Ji Hyun; Lee, Junyoung; Kim, Seung Wook

    2016-04-01

    The waste hydrolysate after dilute acid pretreatment (DAP) of lignocellulosic biomass was utilized to generate electricity using an enzymatic fuel cell (EFC) system. During DAP, the components of biomass containing hemicellulose and other compounds are hydrolyzed, and glucose is solubilized into the dilute acid solution, called as the hydrolysate liquid. Glucose oxidase (GOD) and laccase (Lac) were assembled on the electrode of the anode and cathode, respectively. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were measured, and the maximum power density was found to be 1.254×10(3) μW/cm(2). The results indicate that the hydrolysate from DAP is a reliable electrolyte containing the fuel of EFC. Moreover, the impurities in the hydrolysate such as phenols and furans slightly affected the charge transfer on the surface of the electrode, but did not affect the power generation of the EFC system in principal. PMID:26920478

  13. Engineering aptazyme switches for conditional gene expression in mammalian cells utilizing an in vivo screening approach.

    PubMed

    Rehm, Charlotte; Klauser, Benedikt; Hartig, Jörg S

    2015-01-01

    Artificial RNA switches are an emerging class of genetic controllers suitable for synthetic biology applications. Aptazymes are fusions composed of an aptamer domain and a self-cleaving ribozyme. The utilization of aptazymes for conditional gene expression displays several advantages over employing conventional transcription factor-based techniques as aptazymes require minimal genomic space, fulfill their function without the need of protein cofactors, and most importantly are reprogrammable with respect to ligand selectivity and the RNA function to be regulated. Technologies that enable the generation of aptazymes to defined input ligands are of interest for the construction of biocomputing devices and biosensing applications. In this chapter we present a method that facilitates the in vivo screening of randomized pools of aptazymes in mammalian cells. PMID:25967058

  14. Copper catalysis for enhancement of cobalt leaching and acid utilization efficiency in microbial fuel cells.

    PubMed

    Liu, Yaxuan; Shen, Jingya; Huang, Liping; Wu, Dan

    2013-11-15

    Enhancement of both cobalt leaching from LiCoO2 and acid utilization efficiency (AUE) in microbial fuel cells (MFCs) was successfully achieved by the addition of Cu(II). A dosage of 10mg/L Cu(II) improved both cobalt leaching up to 308% and AUE of 171% compared to the controls with no presence of Cu(II). The apparent activation energy of cobalt leaching catalyzed by Cu(II) in MFCs was only 11.8 kJ/mol. These results demonstrate cobalt leaching in MFCs using Cu(II) as a catalyst may be an effective strategy for cobalt recovery and recycle of spent Li-ion batteries, and the evidence of influence factors including solid/liquid ratio, temperature, and pH and solution conductivity can contribute to improving understanding of and optimizing cobalt leaching catalyzed by Cu(II) in MFCs. PMID:24007993

  15. Parkin Controls Dopamine Utilization in Human Midbrain Dopaminergic Neurons Derived from Induced Pluripotent Stem Cells

    PubMed Central

    Jiang, Houbo; Ren, Yong; Yuen, Eunice Y; Zhong, Ping; Ghaedi, Mahboobe; Hu, Zhixing; Azabdaftari, Gissou; Nakaso, Kazuhiro; Yan, Zhen; Feng, Jian

    2012-01-01

    Parkinson’s disease (PD) is defined by the degeneration of nigral dopaminergic (DA) neurons and can be caused by monogenic mutations of genes such as parkin. The lack of phenotype in parkin knockout mice suggests that human nigral DA neurons have unique vulnerabilities. Through the generation and analyses of induced pluripotent stem cells (iPSCs) from normal subjects and PD patients with parkin mutations, we show here that loss of parkin in human midbrain DA neurons greatly increased the transcription of monoamine oxidases and oxidative stress, significantly reduced DA uptake and increased spontaneous DA release. Lentiviral expression of parkin, but not its PD-linked mutant, rescued all the phenotypes. The results suggest that parkin controls dopamine utilization in human midbrain DA neurons by enhancing the precision of dopaminergic neurotransmission and suppressing dopamine oxidation. Thus, the study provides novel targets and a physiologically relevant screening platform for disease-modifying therapies of PD. PMID:22314364

  16. Parkin controls dopamine utilization in human midbrain dopaminergic neurons derived from induced pluripotent stem cells.

    PubMed

    Jiang, Houbo; Ren, Yong; Yuen, Eunice Y; Zhong, Ping; Ghaedi, Mahboobe; Hu, Zhixing; Azabdaftari, Gissou; Nakaso, Kazuhiro; Yan, Zhen; Feng, Jian

    2012-01-01

    Parkinson's disease (PD) is defined by the degeneration of nigral dopaminergic (DA) neurons and can be caused by monogenic mutations of genes such as parkin. The lack of phenotype in parkin knockout mice suggests that human nigral DA neurons have unique vulnerabilities. Here we generate induced pluripotent stem cells from normal subjects and PD patients with parkin mutations. We demonstrate that loss of parkin in human midbrain DA neurons greatly increases the transcription of monoamine oxidases and oxidative stress, significantly reduces DA uptake and increases spontaneous DA release. Lentiviral expression of parkin, but not its PD-linked mutant, rescues these phenotypes. The results suggest that parkin controls dopamine utilization in human midbrain DA neurons by enhancing the precision of DA neurotransmission and suppressing dopamine oxidation. Thus, the study provides novel targets and a physiologically relevant screening platform for disease-modifying therapies of PD. PMID:22314364

  17. SPOUTED BED ELECTRODES (SBE) FOR DIRECT UTILIZATION OF CARBON IN FUEL CELLS

    SciTech Connect

    J.M. Calo

    2004-12-01

    This Phase I project was focused on an investigation of spouted bed particulate electrodes for the direct utilization of solid carbon in fuel cells. This approach involves the use of a circulating carbon particle/molten carbonate slurry in the cell that provides a few critical functions: it (1) fuels the cell continuously with entrained carbon particles; (2) brings particles to the anode surfaces hydrodynamically; (3) removes ash from the anode surfaces and the cell hydrodynamically; (4) provides a facile means of cell temperature control due to its large thermal capacitance; (5) provides for electrolyte maintenance and control in the electrode separator(s); and (6) can (potentially) improve carbon conversion rates by ''pre-activating'' carbon particle surfaces via formation of intermediate oxygen surface complexes in the bulk molten carbonate. The approach of this scoping project was twofold: (1) adaptation and application of a CFD code, originally developed to simulate particle circulation in spouted bed electrolytic reactors, to carbon particle circulation in DCFC systems; and (2) experimental investigation of the hydrodynamics of carbon slurry circulation in DCFC systems using simulated slurry mixtures. The CFD model results demonstrated that slurry recirculation can be used to hydrodynamically feed carbon particles to anode surfaces. Variations of internal configurations were investigated in order to explore effects on contacting. It was shown that good contacting with inclined surfaces could be achieved even when the particles are of the same density as the molten carbonate. The use of CO{sub 2} product gas from the fuel cell as a ''lift-gas'' to circulate the slurry was also investigated with the model. The results showed that this is an effective method of slurry circulation; it entrains carbon particles more effectively in the draft duct and produces a somewhat slower recirculation rate, and thus higher residence times on anode surfaces, and can be

  18. Hospital utilization patterns and costs for adult sickle cell patients in Illinois.

    PubMed Central

    Woods, K; Karrison, T; Koshy, M; Patel, A; Friedmann, P; Cassel, C

    1997-01-01

    OBJECTIVES: To determine population size, demographic characteristics, hospital utilization patterns, the specialties of physicians providing care, and costs for hospitalized adult sickle cell patients in Illinois. METHODS: A statewide, administrative dataset for the two-year period from january 1992 through December 1993 was analyzed retrospectively. RESULTS: There were 8403 admissions among 1189 individual sickle cell patients for the two-year period. Eighty-five percent of patients resided in the Chicago metropolitan area. The median age of the 1189 patients was 29; two-thirds had Medicaid or Medicare coverage. Emergency departments were the primary source of admissions (85.7%). The most common admitting diagnosis was painful crisis (97.4%), and average length of stay was four days. The median number of admissions per patient was three; most patients (85%) used only one or two hospitals. A small group used more than four hospitals and accounted for 23% of statewide admissions. Primary care physicians cared for most patients, and total hospitalization charges were more than $59 million. CONCLUSIONS: In Illinois the adult sickle cell population is concentrated in major urban centers, primarily the Chicago metropolitan area. These patients accounted for approximately 8400 admissions and more than $59 million in hospital charges during the two-year study period. A small group of patients used multiple hospitals and accounted for more than 23% of total hospitalization charges. This study shows the necessity of and provides a useful framework for developing targeted programs for adult sickle cell patients as well as for training physicians to efficiently provide comprehensive health care services for this population. PMID:9018288

  19. Differential utilization of binding loop flexibility in T cell receptor ligand selection and cross-reactivity.

    PubMed

    Ayres, Cory M; Scott, Daniel R; Corcelli, Steven A; Baker, Brian M

    2016-01-01

    Complementarity determining region (CDR) loop flexibility has been suggested to play an important role in the selection and binding of ligands by T cell receptors (TCRs) of the cellular immune system. However, questions remain regarding the role of loop motion in TCR binding, and crystallographic structures have raised questions about the extent to which generalizations can be made. Here we studied the flexibility of two structurally well characterized αβ TCRs, A6 and DMF5. We found that the two receptors utilize loop motion very differently in ligand binding and cross-reactivity. While the loops of A6 move rapidly in an uncorrelated fashion, those of DMF5 are substantially less mobile. Accordingly, the mechanisms of binding and cross-reactivity are very different between the two TCRs: whereas A6 relies on conformational selection to select and bind different ligands, DMF5 uses a more rigid, permissive architecture with greater reliance on slower motions or induced-fit. In addition to binding site flexibility, we also explored whether ligand-binding resulted in common dynamical changes in A6 and DMF5 that could contribute to TCR triggering. Although binding-linked motional changes propagated throughout both receptors, no common features were observed, suggesting that changes in nanosecond-level TCR structural dynamics do not contribute to T cell signaling. PMID:27118724

  20. Differential utilization of binding loop flexibility in T cell receptor ligand selection and cross-reactivity

    PubMed Central

    Ayres, Cory M.; Scott, Daniel R.; Corcelli, Steven A.; Baker, Brian M.

    2016-01-01

    Complementarity determining region (CDR) loop flexibility has been suggested to play an important role in the selection and binding of ligands by T cell receptors (TCRs) of the cellular immune system. However, questions remain regarding the role of loop motion in TCR binding, and crystallographic structures have raised questions about the extent to which generalizations can be made. Here we studied the flexibility of two structurally well characterized αβ TCRs, A6 and DMF5. We found that the two receptors utilize loop motion very differently in ligand binding and cross-reactivity. While the loops of A6 move rapidly in an uncorrelated fashion, those of DMF5 are substantially less mobile. Accordingly, the mechanisms of binding and cross-reactivity are very different between the two TCRs: whereas A6 relies on conformational selection to select and bind different ligands, DMF5 uses a more rigid, permissive architecture with greater reliance on slower motions or induced-fit. In addition to binding site flexibility, we also explored whether ligand-binding resulted in common dynamical changes in A6 and DMF5 that could contribute to TCR triggering. Although binding-linked motional changes propagated throughout both receptors, no common features were observed, suggesting that changes in nanosecond-level TCR structural dynamics do not contribute to T cell signaling. PMID:27118724

  1. Analysis of gas products from direct utilization of carbon in a solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Siengchum, Tritti; Guzman, Felipe; Chuang, Steven S. C.

    2012-09-01

    The evolution of gases from direct utilization of carbon in a solid oxide fuel cell (C-SOFC) was studied by potentiostatic/galvanostatic discharge of a fuel cell with coconut carbon, a carbonaceous material with low ash and sulfur content. Operation of C-SOFC at 750 °C produced less CO and more CO2 than those predicted by thermodynamic calculation using total Gibbs free energy minimization method. The addition of CO2 to the anode chamber increased CO formation and maximum power density from 0.09 W cm-2 to 0.13 W cm-2, indicating the occurrence of Boudouard reaction (CO2 + C ⇔ 2CO) coupling with CO electrochemical oxidation on the C-SOFC. Analysis of CO and CO2 concentration as a function of current and voltage revealed that electricity was mainly produced from the electrochemical oxidation of carbon at low current density and produced from the electrochemical oxidation of CO at high current density. The results suggest the electrochemical oxidation of solid carbon is more mass transfer limited than electrochemical oxidation of CO.

  2. A 16 Month Survey of Cyclosporine Utilization Evaluation in Allogeneic Hematopoietic Stem Cell Transplant Recipients

    PubMed Central

    Tavakoli Ardakani, Maria; Tafazoli, Ali; Mehdizadeh, Mahshid; Hajifathali, Abbas; Dadashzadeh, Simin

    2016-01-01

    Objectives: Graft versus host disease (GVHD) is a life threatening reaction in the stem cell transplantation process. Nowadays Cyclosporine is the most commonly utilized agent for GVHD prophylaxis and it has a major role in successful transplantation. Cyclosporine has been applied for many years in this field but it could be stated that currently no general consensus is available for its optimal method of administration. Conditions related to cyclosporine administration and possible related adverse reactions observed closely in our patients with the aim of constructing a comprehensive practice guideline in the future. Patients and Methods: Allogeneic stem cell transplant recipients who have been taking cyclosporine were monitored during and after their hospitalization while recording all observations on predefined questionnaires on the basis of periodic clinical and laboratory examinations for a 16 month period. Results: Mean recorded duration of infusions was 1.44 ± 0.68 h and by twice daily administration, means intravenous and oral dose was 101.85 ± 22.03 mg and 219.28 ± 63.9 mg, respectively. A mean CsA trough level after about 12 h of specified unique doses was 223 ± 65 ng/mL. We found hypertension, nephrotoxicity, neurotoxicity, hypertension, and dyslipidemia in about 14, 20, 48, and 94 percent of patients. Conclusions: This study proposed that permanent guidance of healthcare team according to a fixed and standard method of cyclosporine administration routine with using efficient facilities and protocols would be helpful considerably for an optimal pharmacotherapy. PMID:27610174

  3. Screening of aptamers specific to colorectal cancer cells and stem cells by utilizing On-chip Cell-SELEX

    PubMed Central

    Hung, Lien-Yu; Wang, Chih-Hung; Che, Yu-Jui; Fu, Chien-Yu; Chang, Hwan-You; Wang, Kuan; Lee, Gwo-Bin

    2015-01-01

    Colorectal cancer (CRC) is the most frequently diagnosed cancer around the world, causing about 700,000 deaths every year. It is clear now that a small fraction of CRC, named colorectal cancer stem cells (CSCs) exhibiting self-renewal and extensive proliferative activities, are hard to be eradicated. Unfortunately, highly specific biomarkers for colorectal CSC (CR-CSCs) are lacking that prohibits the development of effective therapeutic strategies. This study designed and manufactured a novel microfluidic system capable of performing a fully automated cell-based, systematic evolution of ligands by exponential enrichment (SELEX) process. Eight CR-CSC/CRC-specific aptamers were successfully selected using the microfluidic chip. Three of the aptamers showed high affinities towards their respective target cells with a dissociation constant of 27.4, 28.5 and 12.3 nM, which are comparable to that of antibodies. PMID:25999049

  4. Utility of KRAS mutation detection using circulating cell-free DNA from patients with colorectal cancer.

    PubMed

    Yamada, Takeshi; Iwai, Takuma; Takahashi, Goro; Kan, Hayato; Koizumi, Michihiro; Matsuda, Akihisa; Shinji, Seiichi; Yamagishi, Aya; Yokoyama, Yasuyuki; Tatsuguchi, Atsushi; Kawagoe, Tatsuro; Kitano, Shiro; Nakayama, Masato; Matsumoto, Satoshi; Uchida, Eiji

    2016-07-01

    In this study, we evaluated the clinical utility of detecting KRAS mutations in circulating cell-free (ccf)DNA of metastatic colorectal cancer patients. We prospectively recruited 94 metastatic colorectal cancer patients. Circulating cell-free DNA was extracted from plasma samples and analyzed for the presence of seven KRAS point mutations. Using the Invader Plus assay with peptide nucleic acid clamping method and digital PCR, KRAS mutations were detected in the ccfDNA in 35 of 39 patients previously determined to have primary tumors containing KRAS mutations using the Luminex method, and in 5 of 55 patients with tumors containing wild-type KRAS. Curative resection was undertaken in 7 of 34 patients with primary and ccfDNA KRAS mutations, resulting in the disappearance of the mutation from the cell-free DNA in five of seven patients. Three of these patients had tumor recurrence and KRAS mutations in their ccfDNA reappeared. Epidermal growth factor receptor blockade was administered to 24 of the KRAS tumor wild-type patients. Of the 24 patients with wild-type KRAS in their primary tumors, three patients had KRAS mutations in their ccfDNA and did not respond to treatment with epidermal growth factor receptor (EGFR) blockade. We also detected a new KRAS mutation in five patients during chemotherapy with EGFR blockade, before disease progression was detectable with imaging. The detection of KRAS mutations in ccfDNA is an attractive approach for predicting both treatment response and acquired resistance to EGFR blockade, and for detecting disease recurrence. PMID:27116474

  5. Compact fuel cell system utilizing a combination of hydrogen storage materials for optimized performance.

    SciTech Connect

    Chan, Jennifer P.; Dedrick, Daniel E.; Gross, Karl J.; Ng, Greg L.

    2004-12-01

    An entirely new class of light-weight reversible hydrides was recently discovered (the Ti-doped alanates)[1]. These NaAIH{sub 4}-based materials have demonstrated reversible hydrogen storage capacities of up to 5 wt%, nearly 4 times the gravimetrically density of commercial metal hydrides. For this reason, they have been considered a breakthrough for hydrogen storage in fuel cell vehicles. This project is the first to publish the use of alanates for the generation of electrical power and the first demonstration of a hydride-fueled elevated-temperature PEM Fuel Cell. Because the kinetics of hydrogen uptake and release by the alanate improves with elevated temperatures, novel concepts were tested for the purpose of developing a highly efficient stand-alone power system. A major focus of this work was on the modeling, design, construction and testing of an integrated fuel cell stack and hydrogen storage system that eliminates the need of complicated heat transfer systems and media. After extensive modeling efforts, a proof-of-concept system was built that employs an integrated fuel cell stack and hydride beds that balancing the generation of fuel cell waste heat with the endothermic release of hydrogen from the alanates. Our demonstration unit was capable of greater than one hour of operation on a single charge of hydrogen from the integrated 173 gram alanate bed. In addition, composite hydride materials with synergistic reaction heats were evaluated and tested to enhance the operational performance of the alanates. The composites provide a unique opportunity to utilize the heat produced from hydriding classic metal hydrides to improve both absorption and desorption rates of the alanates. A particular focus of the mixed storage materials work was to balance the thermodynamics and kinetics of the hydrides for start-up conditions. Modeling of the sorption properties proved invaluable in evaluating the optimum composition of hydrides. The modeling efforts were followed

  6. The Utilization during Mitotic Cell Division of Loci Controlling Meiotic Recombination and Disjunction in DROSOPHILA MELANOGASTER

    PubMed Central

    Baker, Bruce S.; Carpenter, Adelaide T. C.; Ripoll, P.

    1978-01-01

    To inquire whether the loci identified by recombination-defective and disjunction-defective meiotic mutants in Drosophila are also utilized during mitotic cell division, the effects of 18 meiotic mutants (representing 13 loci) on mitotic chromosome stability have been examined genetically. To do this, meiotic-mutant-bearing flies heterozygous for recessive somatic cell markers were examined for the frequencies and types of spontaneous clones expressing the cell markers. In such flies, marked clones can arise via mitotic recombination, mutation, chromosome breakage, nondisjunction or chromosome loss, and clones from these different origins can be distinguished. In addition, meiotic mutants at nine loci have been examined for their effects on sensitivity to killing by UV and X rays.—Mutants at six of the seven recombination-defective loci examined (mei-9, mei-41, c(3)G, mei-W68, mei-S282, mei-352, mei-218) cause mitotic chromosome instability in both sexes, whereas mutants at one locus (mei-218) do not affect mitotic chromosome stability. Thus many of the loci utilized during meiotic recombination also function in the chromosomal economy of mitotic cells.—The chromosome instability produced by mei-41 alleles is the consequence of chromosome breakage, that of mei-9 alleles is primarily due to chromosome breakage and, to a lesser extent, to an elevated frequency of mitotic recombination, whereas no predominant mechanism responsible for the instability caused by c(3)G alleles is discernible. Since these three loci are defective in their responses to mutagen damage, their effects on chromosome stability in nonmutagenized cells are interpreted as resulting from an inability to repair spontaneous lesions. Both mei-W68 and mei-S282 increase mitotic recombination (and in mei-W68, to a lesser extent, chromosome loss) in the abdomen but not the wing. In the abdomen, the primary effect on chromosome stability occurs during the larval period when the abdominal histoblasts

  7. Promoting remyelination: utilizing a viral model of demyelination to assess cell-based therapies

    PubMed Central

    Marro, Brett S; Blanc, Caroline A; Loring, Jeanne F; Cahalan, Michael D; Lane, Thomas E

    2014-01-01

    Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS. While a broad range of therapeutics effectively reduce the incidence of focal white matter inflammation and plaque formation for patients with relapse-remitting forms of MS, a challenge within the field is to develop therapies that allow for axonal protection and remyelination. In the last decade, growing interest has focused on utilizing neural precursor cells (NPCs) to promote remyelination. To understand how NPCs function in chronic demyelinating environments, several excellent pre-clinical mouse models have been developed. One well accepted model is infection of susceptible mice with neurotropic variants of mouse hepatitis virus (MHV) that undergo chronic demyelination exhibiting clinical and histopathologic similarities to MS patients. Combined with the possibility that an environmental agent such as a virus could trigger MS, the MHV model of demyelination presents a relevant mouse model to assess the therapeutic potential of NPCs transplanted into an environment in which inflammatory-mediated demyelination is established. PMID:25245576

  8. Fabrication and Performance of Zirconia Electrolysis Cells for Carbon Dioxide Reduction for Mars In Situ Resource Utilization Applications

    NASA Technical Reports Server (NTRS)

    Minh, N. Q.; Chung, B. W.; Doshi, R.; Lear, G. R.; Montgomery, K.; Ong, E. T.

    1999-01-01

    The use of the Martian atmosphere (95% CO2) to produce oxygen (for propellant and life support) can significantly lower the required launch mass and dramatically reduce the total cost for Mars missions. Zirconia electrolysis cells are one of the technologies being considered for oxygen generation from carbon dioxide in Mars In Situ Resource Utilization (ISRU) production plants. The attractive features of the zirconia cell for this application include simple operation and lightweight, low volume system.

  9. An antigen-specific, four-color, B-cell FluoroSpot assay utilizing tagged antigens for detection.

    PubMed

    Jahnmatz, Peter; Bengtsson, Theresa; Zuber, Bartek; Färnert, Anna; Ahlborg, Niklas

    2016-06-01

    The FluoroSpot assay, a variant of ELISpot utilizing fluorescent detection, has so far been used primarily for assessment of T cells, where simultaneous detection of several cytokines has allowed a more qualitative analysis of functionally distinct T cells. The potential to measure multiple analytes also presents several advantages when analyzing B cells. Our aim was to develop a B-cell FluoroSpot assay adaptable to studies of a variety of antigens. The assay utilizes anti-IgG antibodies immobilized in 96-well filter membrane plates. During cell culture, IgG antibodies secreted by antibody-secreting cells (ASCs) are captured in the vicinity of each of these cells and the specificity of single ASCs is defined using antigens for detection. The antigens were labeled with biotin or peptide tags enabling secondary detection with fluorophore-conjugated streptavidin or tag-specific antibodies. The assay, utilizing up to four different tag systems and fluorophores simultaneously, was evaluated using hybridomas and immunized splenocytes as ASCs. Assay variants were developed that could: i) identify multiple ASCs with different antigen specificities; ii) detect ASCs showing cross-reactivity with different but related antigens; and iii) define the antigen-specificity and, by including anti-IgG subclass detection reagents, simultaneously determine the IgG subclass of antibodies secreted by ASCs. As demonstrated here, the B-cell FluoroSpot assay using tag-based detection systems provides a versatile and powerful tool to investigate antibody responses by individual cells that can be readily adapted to studies of a variety of antigen-specific ASCs. PMID:26930550

  10. A model of the Capital Cost of a natural gas-fired fuel cell based Central Utilities Plant

    SciTech Connect

    Not Available

    1993-06-30

    This model defines the methods used to estimate the cost associated with acquisition and installation of capital equipment of the fuel cell systems defined by the central utility plant model. The capital cost model estimates the cost of acquiring and installing the fuel cell unit, and all auxiliary equipment such as a boiler, air conditioning, hot water storage, and pumps. The model provides a means to adjust initial cost estimates to consider learning associated with the projected level of production and installation of fuel cell systems. The capital cost estimate is an input to the cost of ownership analysis where it is combined with operating cost and revenue model estimates.

  11. Routine Paediatric Sickle Cell Disease (SCD) Outpatient Care in a Rural Kenyan Hospital: Utilization and Costs

    PubMed Central

    Amendah, Djesika D.; Mukamah, George; Komba, Albert; Ndila, Carolyne; Williams, Thomas N.

    2013-01-01

    Background More than 70% of children with sickle cell disease (SCD) are born in sub-Saharan Africa where the prevalence at birth of this disease reaches 2% or higher in some selected areas. There is a dearth of knowledge on comprehensive care received by children with SCD in sub-Saharan Africa and its associated cost. Such knowledge is important for setting prevention and treatment priorities at national and international levels. This study focuses on routine care for children with SCD in an outpatient clinic of the Kilifi District Hospital, located in a rural area on the coast of Kenya. Objective To estimate the per-patient costs for routine SCD outpatient care at a rural Kenyan hospital. Methods We collected routine administrative and primary cost data from the SCD outpatient clinic and supporting departments at Kilifi District Hospital, Kenya. Costs were estimated by evaluating inputs - equipment, medication, supplies, building use, utility, and personnel - to reflect the cost of offering this service within an existing healthcare facility. Annual economic costs were similarly calculated based on input costs, prorated lifetime of equipment and appropriate discount rate. Sensitivity analyses evaluated these costs under different pay scales and different discount rate. Results We estimated that the annual economic cost per patient attending the SCD clinic was USD 138 in 2010 with a range of USD 94 to USD 229. Conclusion This study supplies the first published estimate of the cost of routine outpatient care for children born with SCD in sub-Saharan Africa. Our study provides policy makers with an indication of the potential future costs of maintaining specialist outpatient clinics for children living with SCD in similar contexts. PMID:23593408

  12. A fiber optics system for monitoring utilization of ZnO adsorbent beds during desulfurization for logistic fuel cell applications

    NASA Astrophysics Data System (ADS)

    Sujan, Achintya; Yang, Hongyun; Dimick, Paul; Tatarchuk, Bruce J.

    2016-05-01

    An in-situ fiber optic based technique for direct measurement of capacity utilization of ZnO adsorbent beds by monitoring bed color changes during desulfurization for fuel cell systems is presented. Adsorbents composed of bulk metal oxides (ZnO) and supported metal oxides (ZnO/SiO2 and Cusbnd ZnO/SiO2) for H2S removal at 22 °C are examined. Adsorbent bed utilization at breakthrough is determined by the optical sensor as the maximum derivative of area under UV-vis spectrum from 250 to 800 nm observed as a function of service time. Since the response time of the sensor due to bed color change is close to bed breakthrough time, a series of probes along the bed predicts utilization of the portion of bed prior to H2S breakthrough. The efficacy of the optical sensor is evaluated as a function of inlet H2S concentration, H2S flow rate and desulfurization in presence of CO, CO2 and moisture in feed. A 6 mm optical probe is employed to measure utilization of a 3/16 inch ZnO extrudate bed for H2S removal. It is envisioned that with the application of the optical sensor, desulfurization can be carried out at high adsorbent utilization and low operational costs during on-board miniaturized fuel processing for logistic fuel cell power systems.

  13. A fiber optics system for monitoring utilization of ZnO adsorbent beds during desulfurization for logistic fuel cell applications

    NASA Astrophysics Data System (ADS)

    Sujan, Achintya; Yang, Hongyun; Dimick, Paul; Tatarchuk, Bruce J.

    2016-05-01

    An in-situ fiber optic based technique for direct measurement of capacity utilization of ZnO adsorbent beds by monitoring bed color changes during desulfurization for fuel cell systems is presented. Adsorbents composed of bulk metal oxides (ZnO) and supported metal oxides (ZnO/SiO2 and Cusbnd ZnO/SiO2) for H2S removal at 22 °C are examined. Adsorbent bed utilization at breakthrough is determined by the optical sensor as the maximum derivative of area under UV-vis spectrum from 250 to 800 nm observed as a function of service time. Since the response time of the sensor due to bed color change is close to bed breakthrough time, a series of probes along the bed predicts utilization of the portion of bed prior to H2S breakthrough. The efficacy of the optical sensor is evaluated as a function of inlet H2S concentration, H2S flow rate and desulfurization in presence of CO, CO2 and moisture in feed. A 6 mm optical probe is employed to measure utilization of a 3/16 inch ZnO extrudate bed for H2S removal. It is envisioned that with the application of the optical sensor, desulfurization can be carried out at high adsorbent utilization and low operational costs during on-board miniaturized fuel processing for logistic fuel cell power systems.

  14. Utilization of cellulose microcapillary tubes as a model system for culturing and viral infection of mammalian cells.

    PubMed

    Venter, Eudri; Van Der Merwe, Christiaan F; Van Staden, Vida

    2012-10-01

    Cryofixation by high-pressure freezing (HPF) and freeze substitution (FS) gives excellent preservation of intracellular membranous structures, ideal for ultrastructural investigations of virus infected cells. Conventional sample preparation methods of tissue cultured cells can however disrupt the association between neighboring cells or of viruses with the plasma membrane, which impacts upon the effectiveness whereby virus release from cells can be studied. We established a system for virus infection and transmission electron microscopy preparation of mammalian cells that allowed optimal visualization of membrane release events. African horse sickness virus (AHSV) is a nonenveloped virus that employs two different release mechanisms from mammalian cells, i.e., lytic release through a disrupted plasma membrane and a nonlytic budding-type release. Cellulose microcapillary tubes were used as support layer for culturing Vero cells. The cells grew to a confluent monolayer along the inside of the tubes and could readily be infected with AHSV. Sections of the microcapillary tubes proved easy to manipulate during the HPF procedure, showed no distortion or compression, and yielded well preserved cells in their native state. There was ample cell surface area available for visualization, which allowed detection of both types of virus release at the plasma membrane at a significantly higher frequency than when utilizing other methods. The consecutive culturing, virus infection and processing of cells within microcapillary tubes therefore represent a novel model system for monitoring intracellular virus life cycle and membrane release events, specifically suited to viruses that do not grow to high titers in tissue culture. PMID:22865476

  15. Fabrication and Performance of Zirconia Electrolysis Cells for Cabon Dioxide Reduction for Mars In Situ Resource Utilization Applications

    NASA Technical Reports Server (NTRS)

    Minh, N. Q.; Chung, B. W.; Doshi, R.; Lear, G. R.; Montgomery, K.; Ong, E. T.

    1999-01-01

    Use of the Martian atmosphere (95% CO2) to produce oxygen (for propellant and life support) can significantly lower the required launch mass and dramatically reduce the total cost for Mars missions. Zirconia electrolysis cells are one of the technologies being considered for oxygen generation from carbon dioxide in Mars In Situ Resource Utilization (ISRU) production plants. The attractive features of the zirconia cell for this application include simple operation and lightweight, low volume system. A zirconia electrolysis cell is an all-solid state device, based on oxygen-ion conducting zirconia electrolytes, that electrochemically reduces carbon dioxide to oxygen and carbon monoxide. The cell consists of two porous electrodes (the anode and cathode) separated by a dense zirconia electrolyte. Typical zirconia cells contain an electrolyte layer which is 200 to 400 micrometer thick. The electrical conductivity requirement for the electrolyte necessitates an operating temperature of 9000 to 10000C. Recently, the fabrication of zirconia cells by the tape calendering has been evaluated. This fabrication process provides a simple means of making cells having very thin electrolytes (5 to 30 micrometers). Thin zirconia electrolytes reduce cell ohmic losses, permitting efficient operation at lower temperatures (8000C or below). Thus, tape-calendered cells provides not only the potential of low temperature operation but also the flexibility in operating temperatures. This paper describes the fabrication of zirconia cells by the tape calendering method and discusses the performance results obtained to date.

  16. Clinical Utility of Indium 111–Labeled White Blood Cell Scintigraphy for Evaluation of Suspected Infection

    PubMed Central

    Lewis, Sarah S.; Cox, Gary M.; Stout, Jason E.

    2014-01-01

    Background  We sought to characterize the clinical utility of indium 111 (111In)–labeled white blood cell (WBC) scans by indication, to identify patient populations who might benefit most from this imaging modality. Methods  Medical records for all patients who underwent 111In-labeled WBC scans at our tertiary referral center from 2005 to 2011 were reviewed. Scan indication, results, and final diagnosis were assessed independently by 2 infectious disease physicians. Reviewers also categorized the clinical utility of each scan as helpful vs not helpful with diagnosis and/or management according to prespecified criteria. Cases for which clinical utility could not be determined were excluded from the utility assessment. Results  One hundred thirty-seven scans were included in this analysis; clinical utility could be determined in 132 (96%) cases. The annual number of scans decreased throughout the study period, from 26 in 2005 to 13 in 2011. Forty-one (30%) scans were positive, and 85 (62%) patients were ultimately determined to have an infection. Of the evaluable scans, 63 (48%) scans were deemed clinically useful. Clinical utility varied by scan indication: 111In-labeled WBC scans were more helpful for indications of osteomyelitis (35/50, 70% useful) or vascular access infection (10/15, 67% useful), and less helpful for evaluation of fever of unknown origin (12/35, 34% useful). Conclusions  111In-labeled WBC scans were useful for patient care less than half of the time at our center. Targeted ordering of these scans for indications in which they have greater utility, such as suspected osteomyelitis and vascular access infections, may optimize test utilization. PMID:25734155

  17. Preparatory methods for DNA hydrolysis, cytochemistry, immunocytochemistry and ploidy analysis. Their application to automated and routine diagnostic cytopathology.

    PubMed

    Husain, O A; Watts, K C

    1987-06-01

    A review is presented of some methods used to prepare cytologic specimens for analytical and/or automated studies, with the steps of the procedures detailed in appendices. The preparation of the cell monolayers required for optimal automated cell image analysis and classification, e.g., by the Cytoscan 110, is discussed, as is the preparation of poly-L-lysine-coated slides used in the production of monolayered specimens. These monolayers, which can be prepared from a variety of specimens, are also useful for cytochemical and immunocytochemical studies and DNA ploidy analysis. For DNA analysis, a modified gallocyanin chrome alum staining procedure is described as a stoichiometric alternative to the time-consuming Feulgen reaction. The hydrolysis technique required by the latter method is also detailed. The freeze-fracturing technique for the enhancement of monoclonal antibody immunocytochemical staining of detectable antigens is described, along with an indirect immunoalkaline phosphatase staining method. The use of enzyme cytochemical reactions for glucose 6 phosphate dehydrogenase and lysosomal naphthylamidase is also presented. PMID:3620061

  18. Prismatic sealed nickel-cadmium batteries utilizing fiber structured electrodes. I - New advances in cell design

    NASA Astrophysics Data System (ADS)

    Haschka, Friedrich; Benczur-Urmossy, Gabor; Anderman, Menahem

    Prismatic sealed Ni/Cd cells of fiber structured electrodes offer the potential to fully recharge a battery in a uniquely short time. It was demonstrated that the cells show excellent cycle life. The design is not restricted to 20 Ah rated capacity. Cells of 50 Ah have been built and tested in an electric hybrid vehicle. A specially designed ultra high-power cell of 45 Ah rated capacity for APU cranking in commerical aircraft supplies 50 percent more peak power than vented Ni/Cd sintered plate aircraft cells. The fiber structured sealed FNC-RECOM cell will not require any maintenance.

  19. Disparities in utilization of autologous hematopoietic cell transplantation for treatment of multiple myeloma

    PubMed Central

    Costa, Luciano J.; Huang, Jia-Xing; Hari, Parameswaran N.

    2015-01-01

    Background AHCT is an established therapy for multiple myeloma (MM) with impact in quality of remissions and survival. We analyzed the role of race-ethnicity, sex and age-disparities in AHCT utilization in US. Methods We combined MM incidence derived from SEER-18 with transplant activity reported to the CIBMTR for the period of 2005–2009 to assess the impact of disparities in AHCT. Utilization (number of transplants/new cases) was compared between groups using relative utilization ratio (RUR), defined as [utilization for a given category]/[utilization for the entire population]. Results Data was obtained from 22,462 actual MM cases and 13,311 AHCT. Age-adjusted RUR was 1.17 (1.15–1.19) among non-Hispanic Whites (NHW), higher than in non-Hispanic Blacks (NHB) [0.69 (0.67–0.72), P<0.0002], Hispanics [0.64 (0.60–0.69), p<0.002] and Asians [0.65 (0.58–0.73), P<0.0002]. There was higher AHCT utilization in men than in women among Hispanics (age-adjusted RUR 0.72 vs. 0.56, P=0.007), but not among NHW, NHB or Asians. Sex disparity prevents 1.3% of potential AHCTs in MM (10.4% among Hispanics). Racial-ethnic disparities prevent 13.8% of AHCTs (44.7% in Hispanic and Asians, 39.9% in NHBs). Conclusions Race-ethnicity disparity greatly affects AHCT utilization in MM. Sex disparity plays a lesser role, except among Hispanics. The ongoing decrease in age disparity will continue to drive major increase of AHCT activity. A 2-year and 5-year increase in age of the AHCT population would result in respectively 12% and 32% increase in volume of AHCT. PMID:25555447

  20. Enhanced Electron Lifetimes in Dye-Sensitized Solar Cells Using a Dichromophoric Porphyrin: The Utility of Intermolecular Forces.

    PubMed

    Zhao, Long; Wagner, Pawel; van der Salm, Holly; Gordon, Keith C; Mori, Shogo; Mozer, Attila J

    2015-10-01

    Electron lifetimes in dye-sensitized solar cells employing a porphyrin dye, an organic dye, a 1:1 mixture of the two dyes, and a dichromophoric dye design consisting of the two dyes using a nonconjugated linker were measured, suggesting that the dispersion force of the organic dyes has a significant detrimental effect on the electron lifetime and that the dichromophoric design can be utilized to control the effect of the dispersion force. PMID:26375165

  1. A systematic review of the association between depression and health care utilization in children and adults with sickle cell disease.

    PubMed

    Jonassaint, Charles R; Jones, Victor L; Leong, Sharlene; Frierson, Georita M

    2016-07-01

    Patients with sickle cell disease (SCD) experience a disproportionately high use of health care resources. Several studies have examined depression and other negative mood states as risk factors for increased health care utilization; however, there have been no systematic reviews examining and summarizing this evidence in SCD. The aim of this systematic review, therefore, was to determine whether depression or depressive symptoms are associated with health care utilization among children and adults with SCD. We followed a quantitative systematic review protocol based on the Preferred Reporting Items for Systematic Reviews and Meta- Analyses guidelines and performed a literature search of records from January 1980 to April 2014 using six databases. Empirical studies were eligible if the sample was primarily composed of patients with SCD and included data on depression, mood disorder diagnosis or depressive symptoms and health care utilization. We included 12 studies involving 54 036 unique participants. The prevalence estimates for depression ranged from 2-57%. Seven studies found a significant, or marginally significant, association between depression and utilization while five did not. Patients reporting depression had an estimated 2·8 times greater relative risk of being a high utilizer, and 2·9 versus 1·8 hospitalizations per year on average compared to patients without depression. Overall, depressive symptoms are common in SCD and may increase risk for poor outcomes including health care utilization. The available studies on depression in SCD, however, are limited by small sample sizes, retrospective designs or short follow-up. This systematic review found a modest association between depression and health care utilization in SCD. PMID:26991317

  2. Utilization of GaN:Eu 3+ nanocrystals for the detection of programmed cell death

    NASA Astrophysics Data System (ADS)

    Bilyy, R.; Podhorodecki, A.; Nyk, M.; Stoika, R.; Zaichenko, A.; Zatryb, G.; Misiewicz, J.; Strek, W.

    2008-04-01

    In the current study we propose to use a new system for labeling biological processes. Gallium nitride nanocrystals doped by europium ions (nc-GaN:Eu 3+) have been obtained and used to identify the cells undergoing process of programmed cell death. Obtained by combustion method, GaN:Eu 3+ fluorescent nanocrystals have been covered with the polymeric envelope, bearing epoxy groups. Carbohydrate-binding protein-lectin-specifically recognizing cells undergoing programmed cell death was conjugated to the envelope of nanoparticles. Incubation of alive and dead cells with nanoparticles suspension and subsequent analysis using fluorescent and phase-contrast microscopy revealed predominate binding of nanoparticles to dead cells, while intact cell did not bind nanoparticles under the same conditions.

  3. Improved drug targeting of cancer cells by utilizing actively targetable folic acid-conjugated albumin nanospheres.

    PubMed

    Shen, Zheyu; Li, Yan; Kohama, Kazuhiro; Oneill, Brian; Bi, Jingxiu

    2011-01-01

    Folic acid-conjugated albumin nanospheres (FA-AN) have been developed to provide an actively targetable drug delivery system for improved drug targeting of cancer cells with reduced side effects. The nanospheres were prepared by conjugating folic acid onto the surface of albumin nanospheres using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) as a catalyst. To test the efficacy of these nanospheres as a potential delivery platform, doxorubicin-loaded albumin nanospheres (DOX-AN) and doxorubicin-loaded FA-AN (FA-DOX-AN) were prepared by entrapping DOX (an anthracycline, antibiotic drug widely used in cancer chemotherapy that works by intercalating DNA) into AN and FA-AN nanoparticles. Cell uptake of the DOX was then measured. The results show that FA-AN was incorporated into HeLa cells (tumor cells) only after 2.0h incubation, whereas HeLa cells failed to incorporate albumin nanospheres without conjugated folic acid after 4.0h incubation. When HeLa cells were treated with the DOX-AN, FA-DOX-AN nanoparticles or free DOX, cell viability decreased with increasing culture time (i.e. cell death increases with time) over a 70h period. Cell viability was always the lowest for free DOX followed by FA-DOX-AN4 and then DOX-AN. In a second set of experiments, HeLa cells washed to remove excess DOX after an initial incubation for 2h were incubated for 70h. The corresponding cell viability was slightly higher when the cells were treated with FA-DOX-AN or free DOX whilst cells treated with DOX-AN nanoparticles remained viable. The above experiments were repeated for non-cancerous, aortic smooth muscle cells (AoSMC). As expected, cell viability of the HeLa cells (with FA receptor alpha, FRα) and AoSMC cells (without FRα) decreased rapidly with time in the presence of free DOX, but treatment with FA-DOX-AN resulted in selective killing of the tumor cells. These results indicated that FA-AN may be used as a promising actively targetable drug delivery system to improve drug

  4. Radiation survival of murine and human melanoma cells utilizing two assay systems: monolayer and soft agar.

    PubMed Central

    Yohem, K. H.; Slymen, D. J.; Bregman, M. D.; Meyskens, F. L.

    1988-01-01

    The radiation response of murine and human melanoma cells assayed in bilayer soft agar and monolayer was examined. Cells from the murine melanoma Cloudman S91 CCL 53.1 cell line and three human melanoma cell strains (C8146C, C8161, and R83-4) developed in our laboratory were irradiated by single dose X-rays and plated either in agar or on plastic. D0 values were the same within 95% confidence intervals for cells from the human melanoma cell strains C8146C, C8161, and R83-4 but were dissimilar for the murine cell line CCL 53.1 Dq values were different for all cells studied. The shape of the survival curve for all four melanomas was not identical for cells assayed in soft agar versus cells grown on plastic. This would indicate that apparent radiosensitivity was influenced by the method of assay although there were no apparent consistent differences between the curves generated by monolayer or bilayer soft agar assays. PMID:3348949

  5. Aspartate Rescues S-phase Arrest Caused by Suppression of Glutamine Utilization in KRas-driven Cancer Cells.

    PubMed

    Patel, Deven; Menon, Deepak; Bernfeld, Elyssa; Mroz, Victoria; Kalan, Sampada; Loayza, Diego; Foster, David A

    2016-04-22

    During G1-phase of the cell cycle, normal cells respond first to growth factors that indicate that it is appropriate to divide and then later in G1 to the presence of nutrients that indicate sufficient raw material to generate two daughter cells. Dividing cells rely on the "conditionally essential" amino acid glutamine (Q) as an anaplerotic carbon source for TCA cycle intermediates and as a nitrogen source for nucleotide biosynthesis. We previously reported that while non-transformed cells arrest in the latter portion of G1 upon Q deprivation, mutant KRas-driven cancer cells bypass the G1 checkpoint, and instead, arrest in S-phase. In this study, we report that the arrest of KRas-driven cancer cells in S-phase upon Q deprivation is due to the lack of deoxynucleotides needed for DNA synthesis. The lack of deoxynucleotides causes replicative stress leading to activation of the ataxia telangiectasia and Rad3-related protein (ATR)-mediated DNA damage pathway, which arrests cells in S-phase. The key metabolite generated from Q utilization was aspartate, which is generated from a transaminase reaction whereby Q-derived glutamate is converted to α-ketoglutarate with the concomitant conversion of oxaloacetate to aspartate. Aspartate is a critical metabolite for both purine and pyrimidine nucleotide biosynthesis. This study identifies the molecular basis for the S-phase arrest caused by Q deprivation in KRas-driven cancer cells that arrest in S-phase in response to Q deprivation. Given that arresting cells in S-phase sensitizes cells to apoptotic insult, this study suggests novel therapeutic approaches to KRas-driven cancers. PMID:26921316

  6. Numerical analysis of acoustic impedance microscope utilizing acoustic lens transducer to examine cultured cells.

    PubMed

    Gunawan, Agus Indra; Hozumi, Naohiro; Takahashi, Kenta; Yoshida, Sachiko; Saijo, Yoshifumi; Kobayashi, Kazuto; Yamamoto, Seiji

    2015-12-01

    A new technique is proposed for non-contact quantitative cell observation using focused ultrasonic waves. This technique interprets acoustic reflection intensity into the characteristic acoustic impedance of the biological cell. The cells are cultured on a plastic film substrate. A focused acoustic beam is transmitted through the substrate to its interface with the cell. A two-dimensional (2-D) reflection intensity profile is obtained by scanning the focal point along the interface. A reference substance is observed under the same conditions. These two reflections are compared and interpreted into the characteristic acoustic impedance of the cell based on a calibration curve that was created prior to the observation. To create the calibration curve, a numerical analysis of the sound field is performed using Fourier Transforms and is verified using several saline solutions. Because the cells are suspended by two plastic films, no contamination is introduced during the observation. In a practical observation, a sapphire lens transducer with a center frequency of 300 MHz was employed using ZnO thin film. The objects studied were co-cultured rat-derived glial (astrocyte) cells and glioma cells. The result was the clear observation of the internal structure of the cells. The acoustic impedance of the cells was spreading between 1.62 and 1.72 MNs/m(3). Cytoskeleton was indicated by high acoustic impedance. The introduction of cytochalasin-B led to a significant reduction in the acoustic impedance of the glioma cells; its effect on the glial cells was less significant. It is believed that this non-contact observation method will be useful for continuous cell inspections. PMID:26163739

  7. Label-free and quantitative evaluation of cytotoxicity based on surface nanostructure and biophysical property of cells utilizing AFM.

    PubMed

    Lee, Young Ju; Lee, Gi-Ja; Kang, Sung Wook; Cheong, Youjin; Park, Hun-Kuk

    2013-06-01

    In this study, the four commonly used cytotoxicity assays and the mechanical properties as evaluated by atomic force microscopy (AFM) were compared in a cellular system. A cytotoxicity assay is the first and most essential test to evaluate biocompatibility of various toxic substances. Many of the cytotoxicity methods require complicated and labor-intensive process, as well as introduce experimental error. In addition, these methods cannot provide instantaneous and quantitative cell viability information. AFM has become an exciting analytical tool in medical, biological, and biophysical research due to its unique abilities. AFM-based force-distance curve measurements precisely measure the changes in the biophysical properties of the cell. Therefore, we observed the morphological changes and mechanical property changes in L929 cells following sodium lauryl sulfate (SLS) treatment utilizing AFM. AFM imaging showed that the toxic effects of SLS changed not only the spindle-like shape of L929 cells into a round shape, but also made a rough cell surface. As the concentration of SLS was increased, the surface roughness of L929 cell was increased, and stiffness decreased. We confirmed that inhibition of proliferation clearly increased with increases in SLS concentration based on results from MTT, WST, neutral red uptake, and LIVE/DEAD viability/cytotoxicity assays. The estimated IC₅₀ value by AFM analysis was similar to those of other conventional assays and was included within the 95% confidence interval range. We suggest that an AFM quantitative analysis of the morphological and biophysical changes in cells can be utilized as a new method for evaluating cytotoxicity. PMID:23582483

  8. PERTURBATIONS OF THE LIGNIN BIOSYNTHETIC PATHWAY AND THEIR POTENTIAL TO IMPACT PLANT CELL WALL UTILIZATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects on lignification of perturbing most of the genes for enzymes on the monolignol biosynthetic pathway have now been reasonably well studied, particularly in angiosperms. Early studies sought to reduce lignin content with the idea of targeting the key barrier to efficient utilization of pla...

  9. Fuel cell and system for supplying electrolyte thereto utilizing cascade feed

    DOEpatents

    Feigenbaum, Haim

    1984-01-01

    An electrolyte distribution supply system for use with a fuel cell having a wicking medium for drawing electrolyte therein is formed by a set of containers of electrolyte joined to respective fuel cells or groups thereof in a stack of such cells. The electrolyte is separately stored so as to provide for electrical isolation between electrolytes of the individual cells or groups of cells of the stack. Individual storage compartments are coupled by individual tubes, the ends of the respective tubes terminating on the wicking medium in each of the respective fuel cells. The individual compartments are filled with electrolyte by allowing the compartments to overflow such as in a cascading fashion thereby maintaining the requisite depth of electrolyte in each of the storage compartments. The individual compartments can also contain packed carbon fibers to provide a three stage electrolyte distribution system.

  10. The establishment of a production-ready manufacturing process utilizing thin silicon substrates for solar cells

    NASA Technical Reports Server (NTRS)

    Pryor, R. A.

    1980-01-01

    Three inch diameter Czochralski silicon substrates sliced directly to 5 mil, 8 mil, and 27 mil thicknesses with wire saw techniques were procured. Processing sequences incorporating either diffusion or ion implantation technologies were employed to produce n+p or n+pp+ solar cell structures. These cells were evaluated for performance, ease of fabrication, and cost effectiveness. It was determined that the use of 7 mil or even 4 mil wafers would provide near term cost reductions for solar cell manufacturers.

  11. Solid oxide fuel cell bi-layer anode with gadolinia-doped ceria for utilization of solid carbon fuel

    NASA Astrophysics Data System (ADS)

    Kellogg, Isaiah D.; Koylu, Umit O.; Dogan, Fatih

    Pyrolytic carbon was used as fuel in a solid oxide fuel cell (SOFC) with a yttria-stabilized zirconia (YSZ) electrolyte and a bi-layer anode composed of nickel oxide gadolinia-doped ceria (NiO-GDC) and NiO-YSZ. The common problems of bulk shrinkage and emergent porosity in the YSZ layer adjacent to the GDC/YSZ interface were avoided by using an interlayer of porous NiO-YSZ as a buffer anode layer between the electrolyte and the NiO-GDC primary anode. Cells were fabricated from commercially available component powders so that unconventional production methods suggested in the literature were avoided, that is, the necessity of glycine-nitrate combustion synthesis, specialty multicomponent oxide powders, sputtering, or chemical vapor deposition. The easily-fabricated cell was successfully utilized with hydrogen and propane fuels as well as carbon deposited on the anode during the cyclic operation with the propane. A cell of similar construction could be used in the exhaust stream of a diesel engine to capture and utilize soot for secondary power generation and decreased particulate pollution without the need for filter regeneration.

  12. Utility experience with a 250-kW molten carbonate fuel cell cogeneration power plant at NAS Miramar, San Diego

    NASA Astrophysics Data System (ADS)

    Figueroa, R. A.; Otahal, J.

    This paper focuses on the strategy and experience of San Diego Gas and Electric with the development and demonstration of a proof of concept 250-kW internally manifolded heat exchanger (IMHEX®) carbonate fuel cell power plant. The plant was installed, commissioned, and operated by San Diego Gas and Electric (SDG&E) in a cogeneration mode at the Naval Air Station (NAS) at Miramar in San Diego. These activities were part of a collaborative effort between SDG&E and M-C Power's Program team (IMHEX® Team). The IMHEX® Team consists of M-C Power, Bechtel Engineering, Stewart and Stevenson, and the Institute of Gas Technology (IGT). The technical aspects of the plant's commissioning and operation were addressed by my colleague, J. Otahal, in a poster presentation. Our activities in carbonate fuel cell development are unique because of the level of involvement by an investor-owned utility in the development, engineering, installation, operation and maintenance of a fuel cell demonstration plant. The following topics are discussed in this paper: (i) SDG&E's involvement in the development of molten carbonate fuel cell (MCFC) technology; (ii) the active role in engineering and specification of the IMHEX® MCFC demonstration plant; (iii) responsibility for installation, commissioning, and operation; (iv) utility role in technology development and application of MCFC in a restructured and competitive environment; (v) summary.

  13. Hybrid pentacene/a-silicon solar cells utilizing multiple carrier generation via singlet exciton fission

    NASA Astrophysics Data System (ADS)

    Ehrler, Bruno; Musselman, Kevin P.; Böhm, Marcus L.; Friend, Richard H.; Greenham, Neil C.

    2012-10-01

    Silicon dominates the solar cell market because of its abundance, mature production processes, and high efficiencies, with the best solar cells approaching the Shockley-Queisser limit. Multiple exciton photogeneration provides a route to solar cells that surpass the Shockley-Queisser limit, and we report the use of pentacene, for which photogenerated singlet excitons rapidly convert into two lower-energy spin-triplet excitons. We report solar cells that couple amorphous silicon to pentacene. We show that a thin layer of nanocrystals between silicon and pentacene allows simultaneously harnessing low-energy photons absorbed in silicon and high-energy photons absorbed in pentacene, generating two excitons via singlet fission.

  14. The Comparative Utility of Viromer RED and Lipofectamine for Transient Gene Introduction into Glial Cells

    PubMed Central

    Rao, Sudheendra; Morales, Alejo A.; Pearse, Damien D.

    2015-01-01

    The introduction of genes into glial cells for mechanistic studies of cell function and as a therapeutic for gene delivery is an expanding field. Though viral vector based systems do exhibit good delivery efficiency and long-term production of the transgene, the need for transient gene expression, broad and rapid gene setup methodologies, and safety concerns regarding in vivo application still incentivize research into the use of nonviral gene delivery methods. In the current study, aviral gene delivery vectors based upon cationic lipid (Lipofectamine 3000) lipoplex or polyethylenimine (Viromer RED) polyplex technologies were examined in cell lines and primary glial cells for their transfection efficiencies, gene expression levels, and toxicity. The transfection efficiencies of polyplex and lipoplex agents were found to be comparable in a limited, yet similar, transfection setting, with or without serum across a number of cell types. However, differential effects on cell-specific transgene expression and reduced viability with cargo loaded polyplex were observed. Overall, our data suggests that polyplex technology could perform comparably to the market dominant lipoplex technology in transfecting various cells lines including glial cells but also stress a need for further refinement of polyplex reagents to minimize their effects on cell viability. PMID:26539498

  15. Decreased mental health care utilization following a psychosocial intervention in caregivers of hematopoietic stem cell transplant patients.

    PubMed

    Ouseph, Rita; Croy, Calvin; Natvig, Crystal; Simoneau, Teresa; Laudenslager, Mark L

    2014-03-01

    Caregivers are known to experience increased morbidity when compared to noncaregivers. Does an intervention targeting caregiver distress affect their health care utilization? One hundred forty-eight caregivers of allogeneic hematopoietic stem cell transplant patients were randomized to treatment as usual (TAU) or a psychoeducation, paced respiration, and relaxation (PEPRR) intervention. Assessments of caregivers' service utilization were collected at baseline and 1, 3, and 6 months post-transplant. During the first 30 days after patient transplant, caregiver medical and mental health professional service use decreased while support group attendance peaked. Mixed model regressions showed a significant decrease in mental health service use by the PEPRR group (P=0.001). At six months caregivers in TAU had predicted marginal probabilities of mental health services utilization over 10 times as high as caregivers in PEPRR (18.1% vs 1.5%). Groups failed to differ in medical service (P=0.861) or support group (P=0.067) use. We can conclude that participation in PEPRR compared to TAU was associated with reduced mental health service utilization. Caregiver psychosocial support services are critical to improve caregiver outcomes. PMID:25478136

  16. Decreased Mental Health Care Utilization Following a Psychosocial Intervention in Caregivers of Hematopoietic Stem Cell Transplant Patients

    PubMed Central

    Croy, Calvin; Natvig, Crystal; Simoneau, Teresa; Laudenslager, Mark L.

    2014-01-01

    Caregivers are known to experience increased morbidity when compared to noncaregivers. Does an intervention targeting caregiver distress affect their health care utilization? One hundred forty-eight caregivers of allogeneic hematopoietic stem cell transplant patients were randomized to treatment as usual (TAU) or a psychoeducation, paced respiration, and relaxation (PEPRR) intervention. Assessments of caregivers’ service utilization were collected at baseline and 1, 3, and 6 months post-transplant. During the first 30 days after patient transplant, caregiver medical and mental health professional service use decreased while support group attendance peaked. Mixed model regressions showed a significant decrease in mental health service use by the PEPRR group (P=0.001). At six months caregivers in TAU had predicted marginal probabilities of mental health services utilization over 10 times as high as caregivers in PEPRR (18.1% vs 1.5%). Groups failed to differ in medical service (P=0.861) or support group (P=0.067) use. We can conclude that participation in PEPRR compared to TAU was associated with reduced mental health service utilization. Caregiver psychosocial support services are critical to improve caregiver outcomes. PMID:25478136

  17. Utilizing custom-designed galvanotaxis chambers to study directional migration of prostate cells.

    PubMed

    Yang, Hsin-ya; La, Thi Dinh; Isseroff, R Rivkah

    2014-01-01

    The physiological electric field serves specific biological functions, such as directing cell migration in embryo development, neuronal outgrowth and epithelial wound healing. Applying a direct current electric field to cultured cells in vitro induces directional cell migration, or galvanotaxis. The 2-dimensional galvanotaxis method we demonstrate here is modified with custom-made poly(vinyl chloride) (PVC) chambers, glass surface, platinum electrodes and the use of a motorized stage on which the cells are imaged. The PVC chambers and platinum electrodes exhibit low cytotoxicity and are affordable and re-useable. The glass surface and the motorized microscope stage improve quality of images and allow possible modifications to the glass surface and treatments to the cells. We filmed the galvanotaxis of two non-tumorigenic, SV40-immortalized prostate cell lines, pRNS-1-1 and PNT2. These two cell lines show similar migration speeds and both migrate toward the cathode, but they do show a different degree of directionality in galvanotaxis. The results obtained via this protocol suggest that the pRNS-1-1 and the PNT2 cell lines may have different intrinsic features that govern their directional migratory responses. PMID:25549020

  18. Differentiation-Dependent Energy Production and Metabolite Utilization: A Comparative Study on Neural Stem Cells, Neurons, and Astrocytes.

    PubMed

    Jády, Attila Gy; Nagy, Ádám M; Kőhidi, Tímea; Ferenczi, Szilamér; Tretter, László; Madarász, Emília

    2016-07-01

    While it is evident that the metabolic machinery of stem cells should be fairly different from that of differentiated neurons, the basic energy production pathways in neural stem cells (NSCs) or in neurons are far from clear. Using the model of in vitro neuron production by NE-4C NSCs, this study focused on the metabolic changes taking place during the in vitro neuronal differentiation. O2 consumption, H(+) production, and metabolic responses to single metabolites were measured in cultures of NSCs and in their neuronal derivatives, as well as in primary neuronal and astroglial cultures. In metabolite-free solutions, NSCs consumed little O2 and displayed a higher level of mitochondrial proton leak than neurons. In stem cells, glycolysis was the main source of energy for the survival of a 2.5-h period of metabolite deprivation. In contrast, stem cell-derived or primary neurons sustained a high-level oxidative phosphorylation during metabolite deprivation, indicating the consumption of own cellular material for energy production. The stem cells increased O2 consumption and mitochondrial ATP production in response to single metabolites (with the exception of glucose), showing rapid adaptation of the metabolic machinery to the available resources. In contrast, single metabolites did not increase the O2 consumption of neurons or astrocytes. In "starving" neurons, neither lactate nor pyruvate was utilized for mitochondrial ATP production. Gene expression studies also suggested that aerobic glycolysis and rapid metabolic adaptation characterize the NE-4C NSCs, while autophagy and alternative glucose utilization play important roles in the metabolism of stem cell-derived neurons. PMID:27116891

  19. Characterization of human-induced pluripotent stem cell-derived cardiomyocytes: bioenergetics and utilization in safety screening.

    PubMed

    Rana, Payal; Anson, Blake; Engle, Sandra; Will, Yvonne

    2012-11-01

    Cardiotoxicity remains the number one reason for drug withdrawal from the market, and Food and Drug Administration issued black box warnings, thus demonstrating the need for more predictive preclinical safety screening, especially early in the drug discovery process when much chemical substrate is available. Whereas human-ether-a-go-go related gene screening has become routine to mitigate proarrhythmic risk, the development of in vitro assays predicting additional on- and off-target biochemical toxicities will benefit from cellular models exhibiting true cardiomyocyte characteristics such as native tissue-like mitochondrial activity. Human stem cell-derived tissue cells may provide such a model. This hypothesis was tested using a combination of flux analysis, gene and protein expression, and toxicity-profiling techniques to characterize mitochondrial function in induced pluripotent stem cell (iPSC) derived human cardiomyocytes in the presence of differing carbon sources over extended periods in cell culture. Functional analyses demonstrate that iPSC-derived cardiomyocytes are (1) capable of utilizing anaerobic or aerobic respiration depending upon the available carbon substrate and (2) bioenergetically closest to adult heart tissue cells when cultured in galactose or galactose supplemented with fatty acids. We utilized this model to test a variety of kinase inhibitors with known clinical cardiac liabilities for their potential toxicity toward these cells. We found that the kinase inhibitors showed a dose-dependent toxicity to iPSC cardiomyocytes grown in galactose and that oxygen consumption rates were significantly more affected than adenosine triphosphate production. Sorafenib was found to have the most effect, followed by sunitinib, dasatinib, imatinib, lapatinib, and nioltinib. PMID:22843568

  20. Differentiation-Dependent Energy Production and Metabolite Utilization: A Comparative Study on Neural Stem Cells, Neurons, and Astrocytes

    PubMed Central

    Jády, Attila Gy.; Nagy, Ádám M.; Kőhidi, Tímea; Ferenczi, Szilamér; Tretter, László

    2016-01-01

    While it is evident that the metabolic machinery of stem cells should be fairly different from that of differentiated neurons, the basic energy production pathways in neural stem cells (NSCs) or in neurons are far from clear. Using the model of in vitro neuron production by NE-4C NSCs, this study focused on the metabolic changes taking place during the in vitro neuronal differentiation. O2 consumption, H+ production, and metabolic responses to single metabolites were measured in cultures of NSCs and in their neuronal derivatives, as well as in primary neuronal and astroglial cultures. In metabolite-free solutions, NSCs consumed little O2 and displayed a higher level of mitochondrial proton leak than neurons. In stem cells, glycolysis was the main source of energy for the survival of a 2.5-h period of metabolite deprivation. In contrast, stem cell-derived or primary neurons sustained a high-level oxidative phosphorylation during metabolite deprivation, indicating the consumption of own cellular material for energy production. The stem cells increased O2 consumption and mitochondrial ATP production in response to single metabolites (with the exception of glucose), showing rapid adaptation of the metabolic machinery to the available resources. In contrast, single metabolites did not increase the O2 consumption of neurons or astrocytes. In “starving” neurons, neither lactate nor pyruvate was utilized for mitochondrial ATP production. Gene expression studies also suggested that aerobic glycolysis and rapid metabolic adaptation characterize the NE-4C NSCs, while autophagy and alternative glucose utilization play important roles in the metabolism of stem cell-derived neurons. PMID:27116891

  1. Utility-Scale Power Router: Dynamic Control of Grid Assets Using Direct AC Converter Cells

    SciTech Connect

    2010-09-01

    ADEPT Project: Georgia Tech is developing a cost-effective, utility-scale power router that uses an enhanced transformer to more efficiently direct power on the grid. Existing power routing technologies are too expensive for widespread use, but the ability to route grid power to match real-time demand and power outages would significantly reduce energy costs for utilities, municipalities, and consumers. Georgia Tech is adding a power converter to an existing grid transformer to better control power flows at about 1/10th the cost of existing power routing solutions. Transformers convert the high-voltage electricity that is transmitted through the grid into the low-voltage electricity that is used by homes and businesses. The added converter uses fewer steps to convert some types of power and eliminates unnecessary power storage, among other improvements. The enhanced transformer is more efficient, and it would still work even if the converter fails, ensuring grid reliability.

  2. How Shigella Utilizes Ca2+ Jagged Edge Signals during Invasion of Epithelial Cells

    PubMed Central

    Bonnet, Mariette; Tran Van Nhieu, Guy

    2016-01-01

    Shigella, the causative agent of bacillary dysentery invades intestinal epithelial cells using a type III secretion system (T3SS). Through the injection of type III effectors, Shigella manipulates the actin cytoskeleton to induce its internalization in epithelial cells. At early invasion stages, Shigella induces atypical Ca2+ responses confined at entry sites allowing local cytoskeletal remodeling for bacteria engulfment. Global Ca2+ increase in the cell triggers the opening of connexin hemichannels at the plasma membrane that releases ATP in the extracellular milieu, favoring Shigella invasion and spreading through purinergic receptor signaling. During intracellular replication, Shigella regulates inflammatory and death pathways to disseminate within the epithelium. At later stages of infection, Shigella downregulates hemichannel opening and the release of extracellular ATP to dampen inflammatory signals. To avoid premature cell death, Shigella activates cell survival by upregulating the PI3K/Akt pathway and downregulating the levels of p53. Furthermore, Shigella interferes with pro-apoptotic caspases, and orients infected cells toward a slow necrotic cell death linked to mitochondrial Ca2+ overload. In this review, we will focus on the role of Ca2+ responses and their regulation by Shigella during the different stages of bacterial infection. PMID:26904514

  3. Functionality and antidiabetic utility of β- and L-cell containing pseudoislets.

    PubMed

    Green, Alastair D; Vasu, Srividya; Flatt, Peter R

    2016-06-10

    Unavailability of tissue and poor engraftment remain significant obstacles to clinical islet transplantation. Here, the therapeutic potential of pseudoislets generated from the insulin and GLP-1 releasing cell-lines MIN6 and GLUTag was investigated. Glucose and other secretagogues evoked 1.3-5.7 fold increases in insulin secretion from both pseudoislet types. Secretion expressed in relation to basal values did not greatly differ between configurations. Exposure of both types of pseudoislets to ninhydrin, H2O2, streptozotocin or cytokine cocktails decreased viability and increased apoptosis. However, combined pseudoislets exhibited enhanced resistance (1.2-1.7 fold increased LD50, 1.2-1.4 fold decreased apoptosis). Implantation of pseudoislets into streptozotocin-diabetic SCID mice precipitated cell masses containing immunoreactive insulin and GLP-1. Implantation of both pseudoislet types was associated with significant reductions in blood glucose, increased plasma insulin, greater bodyweight, decreased polydipsia and improved glucose tolerance. These changes greatly exaggerated in MIN6 pseudoislet recipients, with mice becoming severely hypoglycaemic. In contract, combined pseudoislet recipients achieved tempered restoration of normoglycaemia and exhibited increased plasma GLP-1, decreased plasma and pancreatic glucagon, increased pancreatic insulin and enhancements in islet β:α cells and the ratio of Ki67: TUNEL positive β-cells. MIN6 pseudoislet implantation increased islet β:α cell ratio but did not affect β-cell proliferation or hormone content. Our observations highlight the potential of combining insulin and GLP-1 cell therapy using heterotypic pseudoislets. PMID:27068377

  4. How Shigella Utilizes Ca(2+) Jagged Edge Signals during Invasion of Epithelial Cells.

    PubMed

    Bonnet, Mariette; Tran Van Nhieu, Guy

    2016-01-01

    Shigella, the causative agent of bacillary dysentery invades intestinal epithelial cells using a type III secretion system (T3SS). Through the injection of type III effectors, Shigella manipulates the actin cytoskeleton to induce its internalization in epithelial cells. At early invasion stages, Shigella induces atypical Ca(2+) responses confined at entry sites allowing local cytoskeletal remodeling for bacteria engulfment. Global Ca(2+) increase in the cell triggers the opening of connexin hemichannels at the plasma membrane that releases ATP in the extracellular milieu, favoring Shigella invasion and spreading through purinergic receptor signaling. During intracellular replication, Shigella regulates inflammatory and death pathways to disseminate within the epithelium. At later stages of infection, Shigella downregulates hemichannel opening and the release of extracellular ATP to dampen inflammatory signals. To avoid premature cell death, Shigella activates cell survival by upregulating the PI3K/Akt pathway and downregulating the levels of p53. Furthermore, Shigella interferes with pro-apoptotic caspases, and orients infected cells toward a slow necrotic cell death linked to mitochondrial Ca(2+) overload. In this review, we will focus on the role of Ca(2+) responses and their regulation by Shigella during the different stages of bacterial infection. PMID:26904514

  5. Herpes B Virus Utilizes Human Nectin-1 but Not HVEM or PILRα for Cell-Cell Fusion and Virus Entry

    PubMed Central

    Fan, Qing; Amen, Melanie; Harden, Mallory; Severini, Alberto; Griffiths, Anthony

    2012-01-01

    To investigate the requirements of herpesvirus entry and fusion, the four homologous glycoproteins necessary for herpes simplex virus (HSV) fusion were cloned from herpes B virus (BV) (or macacine herpesvirus 1, previously known as cercopithecine herpesvirus 1) and cercopithecine herpesvirus 2 (CeHV-2), both related simian simplexviruses belonging to the alphaherpesvirus subfamily. Western blots and cell-based enzyme-linked immunosorbent assay (ELISA) showed that glycoproteins gB, gD, and gH/gL were expressed in whole-cell lysates and on the cell surface. Cell-cell fusion assays indicated that nectin-1, an HSV-1 gD receptor, mediated fusion of cells expressing glycoproteins from both BV and CeHV-2. However, herpesvirus entry mediator (HVEM), another HSV-1 gD receptor, did not facilitate BV- and CeHV-2-induced cell-cell fusion. Paired immunoglobulin-like type 2 receptor alpha (PILRα), an HSV-1 gB fusion receptor, did not mediate fusion of cells expressing glycoproteins from either simian virus. Productive infection with BV was possible only with nectin-1-expressing cells, indicating that nectin-1 mediated entry while HVEM and PILRα did not function as entry receptors. These results indicate that these alphaherpesviruses have differing preferences for entry receptors. The usage of the HSV-1 gD receptor nectin-1 may explain interspecies transfer of the viruses, and altered receptor usage may result in altered virulence, tropism, or pathogenesis in the new host. A heterotypic cell fusion assay resulting in productive fusion may provide insight into interactions that occur to trigger fusion. These findings may be of therapeutic significance for control of deadly BV infections. PMID:22345445

  6. Utilization of the Soft Agar Colony Formation Assay to Identify Inhibitors of Tumorigenicity in Breast Cancer Cells.

    PubMed

    Horibata, Sachi; Vo, Tommy V; Subramanian, Venkataraman; Thompson, Paul R; Coonrod, Scott A

    2015-01-01

    Given the inherent difficulties in investigating the mechanisms of tumor progression in vivo, cell-based assays such as the soft agar colony formation assay (hereafter called soft agar assay), which measures the ability of cells to proliferate in semi-solid matrices, remain a hallmark of cancer research. A key advantage of this technique over conventional 2D monolayer or 3D spheroid cell culture assays is the close mimicry of the 3D cellular environment to that seen in vivo. Importantly, the soft agar assay also provides an ideal tool to rigorously test the effects of novel compounds or treatment conditions on cell proliferation and migration. Additionally, this assay enables the quantitative assessment of cell transformation potential within the context of genetic perturbations. We recently identified peptidylarginine deiminase 2 (PADI2) as a potential breast cancer biomarker and therapeutic target. Here we highlight the utility of the soft agar assay for preclinical anti-cancer studies by testing the effects of the PADI inhibitor, BB-Cl-amidine (BB-CLA), on the tumorigenicity of human ductal carcinoma in situ (MCF10DCIS) cells. PMID:26067809

  7. In vitro activity of bortezomib in cultures of patient tumour cells--potential utility in haematological malignancies.

    PubMed

    Wiberg, Kristina; Carlson, Kristina; Aleskog, Anna; Larsson, Rolf; Nygren, Peter; Lindhagen, Elin

    2009-01-01

    Bortezomib represents a new class of anti-cancer drugs, the proteasome inhibitors. We evaluated the in vitro activity of bortezomib with regard to tumour-type specificity and possible mechanisms of drug resistance in 115 samples of tumour cells from patients and in a cell-line panel, using the short-term fluorometric microculture cytotoxicity assay. Bortezomib generally showed dose-response curves with a steep slope. In patient cells, bortezomib was more active in haematological than in solid tumour samples. Myeloma and chronic myeloid leukaemia were the most sensitive tumour types although with great variability in drug response between the individual samples. Colorectal and kidney cancer samples were the least sensitive. In the cell-line panel, only small differences in response were seen between the different cell lines, and the proteasome inhibitors, lactacystin and MG 262, showed an activity pattern similar to that of bortezomib. The cell-line data suggest that resistance to bortezomib was not mediated by MRP-, PgP, GSH-; tubulin and topo II-associated MDR. Combination experiments indicated synergy between bortezomib and arsenic trioxide or irinotecan. The data support the current use of bortezomib but also points to its potential utility in other tumour types and in combination with cytotoxic drugs. PMID:19016012

  8. Light-splitting photovoltaic system utilizing two dual-junction solar cells

    SciTech Connect

    Xiong, Kanglin; Yang, Hui; Lu, Shulong; Dong, Jianrong; Zhou, Taofei; Wang, Rongxin; Jiang, Desheng

    2010-12-15

    There are many difficulties limiting the further development of monolithic multi-junction solar cells, such as the growth of lattice-mismatched material and the current matching constraint. As an alternative approach, the light-splitting photovoltaic system is investigated intensively in different aspects, including the energy loss mechanism and the choice of energy bandgaps of solar cells. Based on the investigation, a two-dual junction system has been implemented employing lattice-matched GaInP/GaAs and InGaAsP/InGaAs cells grown epitaxially on GaAs and InP substrates, respectively. (author)

  9. Epigallocatechin-3-gallate directly suppresses T cell proliferation through impaired IL-2 utilization and cell cycle progression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epigallocatechin-3-gallate (EGCG), a bioactive component of green tea, has a variety of health impact. Previously we demonstrated that in vitro EGCG supplementation inhibited T cell response in mouse spleen cells. In the present study, we first extended our in vitro observation to in vivo and confir...

  10. Assessing the utility of bipolar membranes for use in photoelectrochemical water-splitting cells.

    PubMed

    Vargas-Barbosa, Nella M; Geise, Geoffrey M; Hickner, Michael A; Mallouk, Thomas E

    2014-11-01

    Membranes are important in water-splitting solar cells because they prevent crossover of hydrogen and oxygen. Here, bipolar membranes (BPMs) were tested as separators in water electrolysis cells. Steady-state membrane and solution resistances, electrode overpotentials, and pH gradients were measured at current densities relevant to solar photoelectrolysis. Under forward bias conditions, electrodialysis of phosphate buffer ions creates a pH gradient across a BPM. Under reverse bias, the BPM can maintain a constant buffer pH on both sides of the cell, but a large membrane potential develops. Thus, the BPM does not present a viable solution for electrolysis in buffered electrolytes. However, the membrane potential is minimized when the anode and cathode compartments of the cell contain strongly basic and acidic electrolytes, respectively. PMID:25256955

  11. Evolution of oxygen utilization in multicellular organisms and implications for cell signalling in tissue engineering

    PubMed Central

    Stamati, Katerina; Mudera, Vivek

    2011-01-01

    Oxygen is one of the critically defining elements resulting in the existence of eukaryotic life on this planet. The rise and fall of this element can be tracked through time and corresponds with the evolution of diverse life forms, development of efficient energy production (oxidative phosphorylation) in single cell organisms, the evolution of multicellular organisms and the regulation of complex cell phenotypes. By understanding these events, we can plot the effect of oxygen on evolution and its direct influence on different forms of life today, from the whole organism to specific cells within multicellular organisms. In the emerging field of tissue engineering, understanding the role of different levels of oxygen for normal cell function as well as control of complex signalling cascades is paramount to effectively build 3D tissues in vitro and their subsequent survival when implanted. PMID:22292107

  12. Utilizing Core–Shell Fibrous Collagen-Alginate Hydrogel Cell Delivery System for Bone Tissue Engineering

    PubMed Central

    Perez, Roman A.; Kim, Meeju; Kim, Tae-Hyun; Kim, Joong-Hyun; Lee, Jae Ho; Park, Jeong-Hui; Knowles, Jonathan C.

    2014-01-01

    Three-dimensional matrices that encapsulate and deliver stem cells with defect-tuned formulations are promising for bone tissue engineering. In this study, we designed a novel stem cell delivery system composed of collagen and alginate as the core and shell, respectively. Mesenchymal stem cells (MSCs) were loaded into the collagen solution and then deposited directly into a fibrous structure while simultaneously sheathing with alginate using a newly designed core–shell nozzle. Alginate encapsulation was achieved by the crosslinking within an adjusted calcium-containing solution that effectively preserved the continuous fibrous structure of the inner cell-collagen part. The constructed hydrogel carriers showed a continuous fiber with a diameter of ∼700–1000 μm for the core and 200–500 μm for the shell area, which was largely dependent on the alginate concentration (2%–5%) as well as the injection rate (20–80 mL/h). The water uptake capacity of the core–shell carriers was as high as 98%, which could act as a pore channel to supply nutrients and oxygen to the cells. Degradation of the scaffolds showed a weight loss of ∼22% at 7 days and ∼43% at 14 days, suggesting a possible role as a degradable tissue-engineered construct. The MSCs encapsulated within the collagen core showed excellent viability, exhibiting significant cellular proliferation up to 21 days with levels comparable to those observed in the pure collagen gel matrix used as a control. A live/dead cell assay also confirmed similar percentages of live cells within the core–shell carrier compared to those in the pure collagen gel, suggesting the carrier was cell compatible and was effective for maintaining a cell population. Cells allowed to differentiate under osteogenic conditions expressed high levels of bone-related genes, including osteocalcin, bone sialoprotein, and osteopontin. Further, when the core–shell fibrous carriers were implanted in a rat calvarium defect, the bone

  13. The utility and limitations of glycosylated human CD133 epitopes in defining cancer stem cells

    PubMed Central

    Bidlingmaier, Scott; Zhu, Xiaodong; Liu, Bin

    2008-01-01

    Human CD133 (human prominin-1), a five transmembrane domain glycoprotein, was originally identified as a cell surface antigen present on CD34+ hematopoietic stem cells. Although the biological function of CD133 is not well understood, antibodies to CD133 epitopes have been widely used to purify hematopoietic stem and progenitor cells. The cancer stem cell (CSC) hypothesis postulates that a rare population of tumor cells possessing increased capacities for self-renewal and tumor initiation is responsible for maintaining the growth of neoplastic tissue. The expression of the CD133 epitopes, AC133 and AC141, has been shown to define a subpopulation of brain tumor cells with significantly increased capacity for tumor initiation in xenograft models. Following the discovery of the AC133/AC141+ population of brain tumor stem cells, the AC133 and AC141 epitopes have been extensively used as markers for purifying CSCs in other solid tumors. There are, however, several issues associated with the use of the AC133 and AC141 CD133 epitopes as markers for CSCs. The antibodies routinely used for purification of AC133 and AC141-positive cells target poorly characterized glycosylated epitopes of uncertain specificity. Discordant expression of the AC133 and AC141 epitopes has been observed, and the epitopes can be absent despite the presence of CD133 protein. In addition, CD133 expression has recently been shown to be modulated by oxygen levels. These factors, in combination with the uncertain biological role of CD133, suggest that the use of CD133 expression as a marker for CSCs should be critically evaluated in each new experimental system and highlight the need for additional CSC surface markers that are directly involved in maintaining CSC properties. PMID:18535813

  14. Conceptual designs for utility load-leveling battery with Li/FeS cells

    SciTech Connect

    Zivi, S. M.; Kacinskas, H.; Pollack, I.; Chilenskas, A. A.; Grieve, W.; McFarland, B. L.; Sudar, S.

    1980-07-01

    In 1978, a conceptual design of a 100 MW-h load-leveling battery system having Li alloy/FeS cells was developed as a result of a joint effort between ANL and Rockwell International. In this conceptual design, the submodule, which was the basic replaceable unit for the system, had a capacity of 240 kW-h and consisted of ninety-six 2.5 kW-h cells. However, a study by Rockwell indicated that the cost for battery hardware, $60 to 80/kW-h (cells and converters not included), was too high. Most of this cost was contributed by the submodule structure and the charge equalization scheme, which was the same as that developed for electric-vehicle batteries. In 1979, subsequent efforts were concentrated on lowering these hardware costs and resulted in the development of three modified designs, which are presented in this report. The first, developed at ANL, consisted of a 30 kW-h cell/submodule and the electric-vehicle equalization scheme. The hardware cost for this modified design was quite low, about $25/kW-h; however, this design was eventually rejected owing to the apparent impracticality of such a large cell. The two other modified designs had more conservative cell designs. One of them, developed at ANL, consisted of a 120 kW-h submodule consisting of one hundred 1.2 kW-h cells; the other, developed at Rockwell, consisted of a 1020 kW-h submodule consisting of four hundred and eight 2.5 kW-h cells. For both of these designs, an alternative method of equalization, in which fixed resistance shunts are used on each cell, was proposed; this equalization method adds little equipment cost to the system and only sacrifices about 4% of the coulombic and energy efficiencies. The cost of battery hardware for these two designs was estimated to be acceptable, about $22 to 60/kW-h. Some questions remain on the assumed capabilities of the cells and the feasibility of the battery hardware.

  15. Enhanced Antiproliferative Effect of Carboplatin in Cervical Cancer Cells Utilizing Folate-Grafted Polymeric Nanoparticles

    NASA Astrophysics Data System (ADS)

    Ji, Jing; Zuo, Ping; Wang, Yue-Ling

    2015-11-01

    Carboplatin (CRB) possesses superior anticancer effect in cervical cancer cells with lower incidence of side effects compared to that of cisplatin. However, CRB suffers from severe side effects due to undesirable tissue distributions which contribute to the low therapeutic efficacy. Here, we report a unique folic acid-conjugated chitosan-coated poly( d- l-lactideco-glycolide) (PLGA) nanoparticles (FPCC) prepared for the selective delivery of carboplatin to the cervical cancer cells. The particles were nanosized and spherical shaped with size less than <200 nm. The presence of protective chitosan layer controlled the overall release rate of CRB from chitosan-coated PLGA nanoparticles (PCC) and FPCC. FPCC displayed a higher cellular uptake capacity in HeLa cells than compared to non-targeted nanoparticles. Selective uptake of FPCC was due to an interaction of folic acid (FA) with the folate receptors alpha (FRs-α) which is overexpressed on the HeLa and promoted active targeting. These results indicated that FPCC had a specific affinity for the cancerous, HeLa cells owing to ligand-receptor (FA-FR-α) recognition. Consistently, FPCC showed superior cytotoxic effect than any other formulations. The IC50 (concentration of the drug required to kill 50 % of the cells) value of FPCC was 0.65 μg/ml while it was 1.08, 1.56, and 2.35 μg/ml for PCC, PLGA NP, and free CRB, respectively. Consistent with the cytotoxicity assay, FPCC induced higher fraction of early as well as late apoptosis cells. Especially, FPCC induced nearly 45 % of early apoptosis cells and more than 35 % in late apoptosis. Therefore, we propose that folate-conjugated nanoparticles might have potential applications in cervical cancer therapy.

  16. Involvement of microtubules in lipoprotein degradation and utilization for steroidogenesis in cultured rat luteal cells

    SciTech Connect

    Rajan, V.P.; Menon, K.M.

    1985-12-01

    Cells isolated from superovulated rat ovaries metabolize low density lipoprotein (LDL) and high density lipoprotein (HDL) of human or rat origin and use the lipoprotein-derived cholesterol as a precursor for progesterone production. Under in vitro conditions, both lipoproteins are internalized and degraded in the lysosomes, although degradation of HDL is of lower magnitude than that of LDL. In this report we have examined the role of cellular microtubules in the internalization and degradation of human LDL and HDL in cultured rat luteal cells. The microtubule depolymerizing agents colchicine, podophyllotoxin, vinblastine, and nocodazole as well as taxol, deuterium oxide, and dimethyl sulfoxide, which are known to rapidly polymerize cellular tubulin into microtubules, were used to block the function of microtubules. When these antimicrotubule agents were included in the incubations, degradation of the apolipoproteins of (/sup 125/I)iodo-LDL and (/sup 125/I)iodo-HDL by the luteal cells was inhibited by 50-85% compared to untreated control values. Maximum inhibitory effects were observed when the cells were preincubated with the inhibitor for at least 4 h at 37 C before treatment with the labeled lipoprotein. Lipoprotein-stimulated progesterone production by luteal cells was also inhibited by 50% or more in the presence of antimicrotubule agents. However, basal and hCG-stimulated progesterone production were unaffected by these inhibitors. The binding of (/sup 125/I)iodo-LDL and (/sup 125/I)iodo-HDL to luteal cell plasma membrane receptors was not affected by the microtubule inhibitors. Although binding was unaffected and degradation was impaired in the presence of the inhibitors, there was no detectable accumulation of undegraded lipoprotein within the cells during the 24 h of study.

  17. Investigation of the effects of external current systems on the MAGSAT data utilizing grid cell modeling techniques

    NASA Technical Reports Server (NTRS)

    Klumpar, D. M. (Principal Investigator)

    1982-01-01

    The feasibility of modeling magnetic fields due to certain electrical currents flowing in the Earth's ionosphere and magnetosphere was investigated. A method was devised to carry out forward modeling of the magnetic perturbations that arise from space currents. The procedure utilizes a linear current element representation of the distributed electrical currents. The finite thickness elements are combined into loops which are in turn combined into cells having their base in the ionosphere. In addition to the extensive field modeling, additional software was developed for the reduction and analysis of the MAGSAT data in terms of the external current effects. Direct comparisons between the models and the MAGSAT data are possible.

  18. Efficient preparation of graphene liquid cell utilizing direct transfer with large-area well-stitched graphene

    NASA Astrophysics Data System (ADS)

    Sasaki, Yuki; Kitaura, Ryo; Yuk, Jong Min; Zettl, Alex; Shinohara, Hisanori

    2016-04-01

    By utilizing graphene-sandwiched structures recently developed in this laboratory, we are able to visualize small droplets of liquids in nanometer scale. We have found that small water droplets as small as several tens of nanometers sandwiched by two single-layer graphene are frequently observed by TEM. Due to the electron beam irradiation during the TEM observation, these sandwiched droplets are frequently moving from one place to another and are subjected to create small bubbles inside. The synthesis of a large area single-domain graphene of high-quality is essential to prepare the graphene sandwiched cell which safely encapsulates the droplets in nanometer size.

  19. Androgen and FSH synergistically stimulate lipoprotein degradation and utilization by ovary granulosa cells

    SciTech Connect

    Schreiber, J.R.; Nakamura, K.; Schmit, V.; Weinstein, D.B.

    1984-01-01

    Androgen can directly modulate the induction of steroidogenic enzymes by FSH (follicle stimulating hormone) in ovary granulosa cells. In studies of its mechanism of action, the authors examined the androgen effect on granulosa cell interaction with lipoproteins, the physiologic source of cholesterol. After granulosa cells were cultured for 48 hours with and without androgen and/or FSH, the cells were incubated for 24 hours with /sup 125/I-lipoproteins (human high density lipoprotein (HDL), rat HDL, or human low density lipoprotein (LDL)). The media were then analyzed for lipoprotein protein coat degradation products (mainly /sup 125/I-monoiodotyrosine) and progestin (mainly 20 alpha-dihydroprogesterone (20 alpha-DHP)). In the absence of FSH and androgen, 2 X 10(5) granulosa cells degraded basal levels of all three lipoproteins, but produced no measurable 20 alpha-DHP. The addition of 10(-7) M androstenedione (A), testosterone (T), or 5 alpha-dihydrotestosterone (DHT) had no effect on lipoprotein protein degradation or 20 alpha-DHP production. FSH alone stimulated lipoprotein protein degradation by 50 to 300% while the addition of androgen synergistically augmented the FSH-stimulated 20 alpha-DHP production as well as protein coat degradation of all three lipoproteins. DHT and T were both effective, indicating that androgens themselves, and not estrogen products, were responsible for the effect on lipoprotein protein degradation and 20 alpha-DHP production.

  20. System for exposing cultured cells to intermittent hypoxia utilizing gas permeable cultureware.

    PubMed

    Polak, Jan; Studer-Rabeler, Karen; McHugh, Holly; Hussain, Mehboob A; Shimoda, Larissa A

    2015-07-01

    Tissue intermittent hypoxia (IH) occurs in obstructive sleep apnea, sickle cell anemia, physical exercise and other conditions. Poor gas solubility and slow diffusion through culture media hampers mimicking IH-induced transitions of O(2) in vitro. We aimed to develop a system enabling exposure of cultured cells to IH and to validate such exposure by real-time O(2) measurements and cellular responses. Standard 24-well culture plates and plates with bottoms made from a gas permeable film were placed in a heated cabinet. Desired cycling of O(2) levels was induced using programmable solenoids to purge mixtures of 95% N(2) + 5% CO(2) or 95% O(2) + 5% CO(2). Dissolved oxygen, gas pressure, temperature, and water evaporation were measured during cycling. IH-induced cellular effects were evaluated by hypoxia inducible factor (HIF) and NF-κB luciferase reporters in HEK296 cells and by insulin secretion in rat insulinoma cells. Oxygen cycling in the cabinet was translated into identical changes of O(2) at the well bottom in gas permeable, but not in standard cultureware. Twenty-four hours of IH exposure increased HIF (112%), NF-κB (111%) and insulin secretion (44%). Described system enables reproducible and prolonged IH exposure in cultured cells while controlling for important environmental factors. PMID:25816360

  1. Tumor glucose utilization with FDG-PET and cell kinetic measurements with IUdR in primary rectal cancer

    SciTech Connect

    Schiepers, C.; Haustermans, K.; Penninckx, F.

    1996-05-01

    Rectal cancer is a common disease. Viable tumor cells show increased FDG uptake, which can be used to monitor radiotherapy (RT). Patients were studied in the fasting state (>6 hrs). 400-555 MBq F-18 FDG was administered i.v. and dynamic imaging started. Arterial blood was withdrawn to determine the plasma input function. A bladder catheter was flushed to clear tracer. Tumor glucose utilization (TuGluc) was calculated with a 3 compartment model, assuming a lumped constant of 1. Cell kinetics were measured with flow cytometry 6-8 hrs after in vivo labeling with iodo-deoxy-uridine (IUdR). Potential doubling time (Tpot) was determined. Two groups were investigated: (1) surgery only (n=9) and (2) before and 2-3 weeks after 30 Gy RT (n=9). For group 2 at baseline, a PET was done and tumor biopsies taken on the same day. The other PET studies were performed 1-2 days before surgery. Consecutive patients with a cT3 tumor without metastasis and over 50 yr were selected and randomized. The protocol was approved by the Human Studied Committee. At baseline TuGluc for group 1 was 222 {plus_minus} 104 nmol/min/ml (mean {plus_minus} 1 sd), and for group 2: 215 {plus_minus} 126 (p=Ns). After RT TuGluc decreased to 77 {plus_minus} 39 (p<.01). Tpot was 3.4 {plus_minus} 1.2 days for group 1 and 2.6 {plus_minus} 2.0 for group 2 at baseline (p=NS). After RT, Tpot slowed down to 5.5 {plus_minus} 3.5 days (p=0.06). A weak negative correlation of -0.2 was found between TuGluc and Tpot, a tendency for increased glucose utilization of faster dividing cells. Tpot is not clearly affected by RT suggesting undisturbed proliferation of viable cells 2-3 weeks after RT. However, TuGluc decreased indicating cell loss and histology revealed down staging in about half of patients. In conclusion: tumor FDG uptake and cell kinetics do not show a strong correlation in rectal cancer. RT results in overall loss of tumor cells and down staging, while proliferation of viable cells is maintained.

  2. Electrochemical electron paramagnetic resonance utilizing loop gap resonators and micro-electrochemical cells.

    PubMed

    Tamski, Mika A; Macpherson, Julie V; Unwin, Patrick R; Newton, Mark E

    2015-09-28

    A miniaturised electrochemical cell design for Electron Paramagnetic Resonance (EPR) studies is reported. The cell incorporates a Loop Gap Resonator (LGR) for EPR investigation of electrochemically generated radicals in aqueous (and other large dielectric loss) samples and achieves accurate potential control for electrochemistry by using micro-wires as working electrodes. The electrochemical behaviour of the cell is analysed with COMSOL finite element models and the EPR sensitivity compared to a commercial TE011 cavity resonator using 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPOL) as a reference. The electrochemical EPR performance is demonstrated using the reduction of methyl viologen as a redox probe in both water and acetonitrile. The data reported herein suggest that sub-micromolar concentrations of radical species can be detected in aqueous samples with accurate potential control, and that subtle solution processes coupled to electron transfer, such as comproportionation reactions, can be studied quantitatively using EPR. PMID:26291423

  3. Evaluation of Gas-Cooled Pressurized Phosphoric Acid Fuel Cells for Electric Utility Power Generation

    NASA Technical Reports Server (NTRS)

    Faroque, M.

    1983-01-01

    Gas cooling is a more reliable, less expensive and a more simple alternative to conventional liquid cooling for heat removal from the phosphoric acid fuel cell (PAFC). The feasibility of gas-cooling was already demonstrated in atmospheric pressure stacks. Theoretical and experimental investigations of gas-cooling for pressurized PAFC are presented. Two approaches to gas cooling, Distributed Gas-Cooling (DIGAS) and Separated Gas-Cooling (SGC) were considered, and a theoretical comparison on the basis of cell performance indicated SGC to be superior to DIGAS. The feasibility of SGC was experimentally demonstrated by operating a 45-cell stack for 700 hours at pressure, and determining thermal response and the effect of other related parameters.

  4. Three-Dimensional Spheroid Cell Culture Model for Target Identification Utilizing High-Throughput RNAi Screens.

    PubMed

    Iles, LaKesla R; Bartholomeusz, Geoffrey A

    2016-01-01

    The intrinsic limitations of 2D monolayer cell culture models have prompted the development of 3D cell culture model systems for in vitro studies. Multicellular tumor spheroid (MCTS) models closely simulate the pathophysiological milieu of solid tumors and are providing new insights into tumor biology as well as differentiation, tissue organization, and homeostasis. They are straightforward to apply in high-throughput screens and there is a great need for the development of reliable and robust 3D spheroid-based assays for high-throughput RNAi screening for target identification and cell signaling studies highlighting their potential in cancer research and treatment. In this chapter we describe a stringent standard operating procedure for the use of MCTS for high-throughput RNAi screens. PMID:27581289

  5. Human Coronavirus NL63 Utilizes Heparan Sulfate Proteoglycans for Attachment to Target Cells

    PubMed Central

    Milewska, Aleksandra; Zarebski, Miroslaw; Nowak, Paulina; Stozek, Karol; Potempa, Jan

    2014-01-01

    ABSTRACT Human coronavirus NL63 (HCoV-NL63) is an alphacoronavirus that was first identified in 2004 in the nasopharyngeal aspirate from a 7-month-old patient with a respiratory tract infection. Previous studies showed that HCoV-NL63 and the genetically distant severe acute respiratory syndrome (SARS)-CoV employ the same receptor for host cell entry, angiotensin-converting enzyme 2 (ACE2), but it is largely unclear whether ACE2 interactions are sufficient to allow HCoV-NL63 binding to cells. The present study showed that directed expression of angiotensin-converting enzyme 2 (ACE2) on cells previously resistant to HCoV-NL63 renders them susceptible, showing that ACE2 protein acts as a functional receptor and that its expression is required for infection. However, comparative analysis showed that directed expression or selective scission of the ACE2 protein had no measurable effect on virus adhesion. In contrast, binding of HCoV-NL63 to heparan sulfates was required for viral attachment and infection of target cells, showing that these molecules serve as attachment receptors for HCoV-NL63. IMPORTANCE ACE2 protein was proposed as a receptor for HCoV-NL63 already in 2005, but an in-depth analysis of early events during virus infection had not been performed thus far. Here, we show that the ACE2 protein is required for viral entry but that it is not the primary binding site on the cell surface. Conducted research showed that heparan sulfate proteoglycans function as adhesion molecules, increasing the virus density on cell surface and possibly facilitating the interaction between HCoV-NL63 and its receptor. Obtained results show that the initial events during HCoV-NL63 infection are more complex than anticipated and that a newly described interaction may be essential for understanding the infection process and, possibly, also assist in drug design. PMID:25187545

  6. Utilization of Microgravity Bioreactor for Differentiation and Growth of Human Vascular Endothelial Cells

    NASA Technical Reports Server (NTRS)

    Chen, Chu-Huang; Pellis, Neal R.

    1997-01-01

    The goal was to delineate mechanisms of genetic responses to angiogenic stimulation of human coronary arterial and dermal microvascular endothelial cells during exposure to microgravity. The NASA-designed rotating-wall vessel was used to create a three-dimensional culture environment with low shear-stress and microgravity simulating that in space. The primary specific aim was to determine whether simulated microgravity enhances endothelial cell growth and whether the growth enhancement is associated by augmented expression of Basic Fibroblast Growth Factor (BFGF) and c-fos, an immediate early gene and component of the transcription factor AP-1.

  7. Nano-photonic organic solar cell architecture for advanced light management utilizing dual photonic crystals

    NASA Astrophysics Data System (ADS)

    Peer, Akshit; Biswas, Rana

    2015-09-01

    Organic solar cells have rapidly increasing efficiencies, but typically absorb less than half of the incident solar spectrum. To increase broadband light absorption, we rigorously design experimentally realizable solar cell architectures based on dual photonic crystals. Our optimized architecture consists of a polymer microlens at the air-glass interface, coupled with a photonic-plasmonic crystal at the metal cathode. The microlens focuses light on the periodic nanostructure that generates strong light diffraction. Waveguiding modes and surface plasmon modes together enhance long wavelength absorption in P3HT-PCBM. The architecture has a period of 500 nm, with absorption and photocurrent enhancement of 49% and 58%, respectively.

  8. Process for utilizing low-cost graphite substrates for polycrystalline solar cells

    NASA Technical Reports Server (NTRS)

    Chu, T. L. (Inventor)

    1978-01-01

    Low cost polycrystalline silicon solar cells supported on substrates were prepared by depositing successive layers of polycrystalline silicon containing appropriate dopants over supporting substrates of a member selected from the group consisting of metallurgical grade polycrystalline silicon, graphite and steel coated with a diffusion barrier of silica, borosilicate, phosphosilicate, or mixtures thereof such that p-n junction devices were formed which effectively convert solar energy to electrical energy. To improve the conversion efficiency of the polycrystalline silicon solar cells, the crystallite size in the silicon was substantially increased by melting and solidifying a base layer of polycrystalline silicon before depositing the layers which form the p-n junction.

  9. Fabrication and characterization of protonic-ceramic fuel cells and electrolysis cells utilizing infiltrated lanthanum nickelate electrodes

    NASA Astrophysics Data System (ADS)

    Babiniec, Sean M.

    High-temperature protonic ceramics (HTPCs) have gained interest as fuel cell and electrolysis cell electrolytes, as well as hydrogen separation membranes. The transport of hydrogen as opposed to oxygen results in several benefits and applications, including higher fuel efficiency, dehydrogenation of fuel streams, and hydrogen-based chemical synthesis. However, limited work has been done in the development of air/steam electrodes for these devices. This work presents the characterization of lanthanum nickelate, La 2NiO4+delta (LN), as a potential air/steam electrode material for use with BaCe0.2Zr0.7Y0.1O3-delta (BCZY27) HTPC electrolytes fabricated by the solid-state reactive sintering technique. Two types of devices were made; a symmetric cell used for electrode characterization, and a full fuel cell/electrolysis cell used for device performance characterization. The symmetric cell consists of a 1 mm thick BCZY27 substrate with identical air/steam electrodes on both sides. Air/steam electrodes were made by infiltrating ˜ 50 nm lanthanum nickelate nanoparticles into a BCZY27 porous backbone. The fuel cell/electrolysis cell consists of a 1mm thick Ni/BCZY27 anode support, a 25 mum thick BCZY27 electrolyte, and a 50 mum thick porous BCZY27 backbone infiltrated with lanthanum nickelate. Through symmetric cell testing, it was found that the electrode polarization resistance decreases with increasing oxygen content, indicating good oxygen reduction reaction characteristics. A minimum polarization resistance was found as 2.58 Ohm-cm2 in 3% humidied oxygen at 700 °C. Full cell testing revealed a peak power density of 27 mW-cm-2 at 700 °C. Hydrogen flux measurements were also taken in the both galvanic/post-galvanic and electrolytic operation. Galvanic/post-galvanic fluxes exhibit a very high faradaic efficiency. However, electrolytic hydrogen fluxes were much lower than the calculated hydrogen faradaic flux, indicating a different charge carrier other than protons is

  10. Biodiesel Production: Utilization of Loofah Sponge to Immobilize Rhizopus chinensis CGMCC #3.0232 Cells as a Whole-Cell Biocatalyst.

    PubMed

    He, Qiyang; Xia, Qianjun; Wang, Yuejiao; Li, Xun; Zhang, Yu; Hu, Bo; Wang, Fei

    2016-07-28

    Rhizopus chinensis cells immobilized on loofah (Luffa cylindrica) sponges were used to produce biodiesel via the transesterification of soybean oil. In whole-cell immobilization, loofah sponge is considered to be a superior alternative to conventional biomass carriers because of its biodegradable and renewable properties. During cell cultivation, Rhizopus chinensis mycelia can spontaneously and firmly adhere to the surface of loofah sponge particles. The optimal conditions for processing 9.65 g soybean oil at 40°C and 180 rpm using a 3:1 methanol-to-oil molar ratio were found to be 8% cell addition and 3-10% water content (depending on the oil's weight). Under optimal conditions, an over 90% methyl ester yield was achieved after the first reaction batch. The operational stability of immobilized Rhizopus chinensis cells was assayed utilizing a 1:1 methanol-to-oil molar ratio, thus resulting in a 16.5-fold increase in half-life when compared with immobilized cells of the widely studied Rhizopus oryzae. These results suggest that transesterification of vegetable oil using Rhizopus chinensis whole cells immobilized onto loofah sponge is an effective approach for biodiesel production. PMID:27090185

  11. Utilization of Lymphoblastoid Cell Lines as a System for the Molecular Modeling of Autism

    ERIC Educational Resources Information Center

    Baron, Colin A.; Liu, Stephenie Y.; Hicks, Chindo; Gregg, Jeffrey P.

    2006-01-01

    In order to provide an alternative approach for understanding the biology and genetics of autism, we performed statistical analysis of gene expression profiles of lymphoblastoid cell lines derived from children with autism and their families. The goal was to assess the feasibility of using this model in identifying autism-associated genes.…

  12. Utilizing insulating nanoparticles as the spacer in laminated flexible polymer solar cells for improved mechanical stability.

    PubMed

    Lu, Yunzhang; Alexander, Clement; Xiao, Zhengguo; Yuan, Yongbo; Zhang, Runyu; Huang, Jinsong

    2012-08-31

    Roll-to-roll lamination is one promising technique to produce large-area organic electronic devices such as solar cells with a large through output. One challenge in this process is the frequent electric point shorting of the cathode and anode by the excess or concentrated applied stress from many possible sources. In this paper, we report a method to avoid electric point shorting by incorporating insulating and hard barium titanate (BaTiO(3)) nanoparticles (NPs) into the active layer to work as a spacer. It has been demonstrated that the incorporated BaTiO(3) NPs in poly(3-hexylthiophene):[6,6]-phenyl-c-61-butyric acid methyl ester (P3HT:PCBM) bulk heterojunction solar cells cause no deleterious effect to the power conversion process of this type of solar cell. The resulting laminated devices with NPs in the active layer display the same efficiency as the devices without NPs, while the laminated devices with NPs can sustain a ten times higher lamination stress of over 6 MPa. The flexible polymer solar cell device with incorporated NPs shows a much smaller survivable curvature radius of 4 mm, while a regular flexible device can only sustain a bending curvature radius of 8 mm before fracture. PMID:22886059

  13. Utility of magnetic cell separation as a molecular sperm preparation technique.

    PubMed

    Said, Tamer M; Agarwal, Ashok; Zborowski, Maciej; Grunewald, Sonja; Glander, Hans-Juergen; Paasch, Uwe

    2008-01-01

    Assisted reproductive techniques (ARTs) have become the treatment of choice in many cases of infertility; however, the current success rates of these procedures remain suboptimal. Programmed cell death (apoptosis) most likely contributes to failed ART and to the decrease in sperm quality after cryopreservation. There is a likelihood that some sperm selected for ART will display features of apoptosis despite their normal appearance, which may be partially responsible for the low fertilization and implantation rates seen with ART. One of the features of apoptosis is the externalization of phosphatidylserine (PS) residues, which are normally present on the inner leaflet of the sperm plasma membrane. Colloidal superparamagnetic microbeads ( approximately 50 nm in diameter) conjugated with annexin V bind to PS and are used to separate dead and apoptotic spermatozoa by magnetic-activated cell sorting (MACS). Cells with externalized PS will bind to these microbeads, whereas nonapoptotic cells with intact membranes do not bind and could be used during ARTs. We have conducted a series of experiments to investigate whether the MACS technology could be used to improve ART outcomes. Our results clearly indicate that integrating MACS as a part of sperm preparation techniques will improve semen quality and cryosurvival rates by eliminating apoptotic sperm. Nonapoptotic spermatozoa prepared by MACS display higher quality in terms of routine sperm parameters and apoptosis markers. The higher sperm quality is represented by an increased oocyte penetration potential and cryosurvival rates. Thus, the selection of nonapoptotic spermatozoa by MACS should be considered to enhance ART success rates. PMID:18077822

  14. Utilizing the green alga Chlamydomonas reinhardtii for microbial electricity generation: a living solar cell.

    PubMed

    Rosenbaum, Miriam; Schröder, Uwe; Scholz, Fritz

    2005-10-01

    By employing living cells of the green alga Chlamydomonas reinhardtii, we demonstrate the possibility of direct electricity generation from microbial photosynthetic activity. The presented concept is based on an in situ oxidative depletion of hydrogen, photosynthetically produced by C. reinhardtii under sulfur-deprived conditions, by polymer-coated electrocatalytic electrodes. PMID:15696280

  15. Essential Domains of Anaplasma phagocytophilum Invasins Utilized to Infect Mammalian Host Cells

    PubMed Central

    Seidman, David; Hebert, Kathryn S.; Truchan, Hilary K.; Miller, Daniel P.; Tegels, Brittney K.; Marconi, Richard T.; Carlyon, Jason A.

    2015-01-01

    Anaplasma phagocytophilum causes granulocytic anaplasmosis, an emerging disease of humans and domestic animals. The obligate intracellular bacterium uses its invasins OmpA, Asp14, and AipA to infect myeloid and non-phagocytic cells. Identifying the domains of these proteins that mediate binding and entry, and determining the molecular basis of their interactions with host cell receptors would significantly advance understanding of A. phagocytophilum infection. Here, we identified the OmpA binding domain as residues 59 to 74. Polyclonal antibody generated against a peptide spanning OmpA residues 59 to 74 inhibited A. phagocytophilum infection of host cells and binding to its receptor, sialyl Lewis x (sLex-capped P-selectin glycoprotein ligand 1. Molecular docking analyses predicted that OmpA residues G61 and K64 interact with the two sLex sugars that are important for infection, α2,3-sialic acid and α1,3-fucose. Amino acid substitution analyses demonstrated that K64 was necessary, and G61 was contributory, for recombinant OmpA to bind to host cells and competitively inhibit A. phagocytophilum infection. Adherence of OmpA to RF/6A endothelial cells, which express little to no sLex but express the structurally similar glycan, 6-sulfo-sLex, required α2,3-sialic acid and α1,3-fucose and was antagonized by 6-sulfo-sLex antibody. Binding and uptake of OmpA-coated latex beads by myeloid cells was sensitive to sialidase, fucosidase, and sLex antibody. The Asp14 binding domain was also defined, as antibody specific for residues 113 to 124 inhibited infection. Because OmpA, Asp14, and AipA each contribute to the infection process, it was rationalized that the most effective blocking approach would target all three. An antibody cocktail targeting the OmpA, Asp14, and AipA binding domains neutralized A. phagocytophilum binding and infection of host cells. This study dissects OmpA-receptor interactions and demonstrates the effectiveness of binding domain-specific antibodies

  16. Immunoglobulin heavy chain variable region gene utilization by B cell hybridomas derived from rheumatoid synovial tissue.

    PubMed

    Brown, C M; Longhurst, C; Haynes, G; Plater-Zyberk, C; Malcolm, A; Maini, R N

    1992-08-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disease that primarily affects synovial joints. Activated B lymphocytes and plasma cells are present in the synovial tissue and are thought to contribute to the immunopathology of the rheumatoid joint. To investigate rheumatoid synovial B lymphocytes, we have generated B cell hybridomas from synovial tissue of an RA patient. Here we describe the immunoglobulin VH gene repertoire of eight IgM- and 10 IgG-secreting synovial-derived hybridomas. The VH4 gene family is highly represented (38.5%) in this panel of hybridomas compared with the frequency of VH4 gene expression in circulating B lymphocytes reported previously (19-22%) and with the VH4 gene frequency we observed in a panel of hybridomas derived in the same manner from the spleen and tonsil of normal individuals (19%). The increased frequency of VH4 gene expression was not due to the expansion of a single B cell clone in vivo as none of these hybridomas was clonally related. Two synovial-derived hybridomas secreted autoantibodies; one (VH3+) secreted an IgM-rheumatoid factor (RF) and the other (VH4+) secreted IgM with polyreactive binding to cytoskeletal proteins and cardiolipin. The antibodies secreted by the remaining synovial-derived hybridomas were not reactive with the autoantigens tested. The VH gene usage in a proportion (5/17) of synovial-derived hybridomas that expressed CD5 antigen provided preliminary evidence that CD5+ B cells in RA synovium have a similar increase of VH4 gene expression reported for CD5+ B cells from normal individuals and patients with chronic lymphocytic leukaemia. PMID:1379132

  17. Hydrogen Fuel Cells and Storage Technology: Fundamental Research for Optimization of Hydrogen Storage and Utilization

    SciTech Connect

    Perret, Bob; Heske, Clemens; Nadavalath, Balakrishnan; Cornelius, Andrew; Hatchett, David; Bae, Chusung; Pang, Tao; Kim, Eunja; Hemmers, Oliver

    2011-03-28

    Design and development of improved low-cost hydrogen fuel cell catalytic materials and high-capacity hydrogenn storage media are paramount to enabling the hydrogen economy. Presently, effective and durable catalysts are mostly precious metals in pure or alloyed form and their high cost inhibits fuel cell applications. Similarly, materials that meet on-board hydrogen storage targets within total mass and volumetric constraints are yet to be found. Both hydrogen storage performance and cost-effective fuel cell designs are intimately linked to the electronic structure, morphology and cost of the chosen materials. The FCAST Project combined theoretical and experimental studies of electronic structure, chemical bonding, and hydrogen adsorption/desorption characteristics of a number of different nanomaterials and metal clusters to develop better fundamental understanding of hydrogen storage in solid state matrices. Additional experimental studies quantified the hydrogen storage properties of synthesized polyaniline(PANI)/Pd composites. Such conducting polymers are especially interesting because of their high intrinsic electron density and the ability to dope the materials with protons, anions, and metal species. Earlier work produced contradictory results: one study reported 7% to 8% hydrogen uptake while a second study reported zero hydrogen uptake. Cost and durability of fuel cell systems are crucial factors in their affordability. Limits on operating temperature, loss of catalytic reactivity and degradation of proton exchange membranes are factors that affect system durability and contribute to operational costs. More cost effective fuel cell components were sought through studies of the physical and chemical nature of catalyst performance, characterization of oxidation and reduction processes on system surfaces. Additional development effort resulted in a new hydrocarbon-based high-performance sulfonated proton exchange membrane (PEM) that can be manufactured at low

  18. Clostridium beijerinckii Cells Expressing Neocallimastix patriciarum Glycoside Hydrolases Show Enhanced Lichenan Utilization and Solvent Production

    PubMed Central

    López-Contreras, Ana M.; Smidt, Hauke; van der Oost, John; Claassen, Pieternel A. M.; Mooibroek, Hans; de Vos, Willem M.

    2001-01-01

    Growth and the production of acetone, butanol, and ethanol by Clostridium beijerinckii NCIMB 8052 on several polysaccharides and sugars were analyzed. On crystalline cellulose, growth and solvent production were observed only when a mixture of fungal cellulases was added to the medium. On lichenan growth and solvent production occurred, but this polymer was only partially utilized. To increase utilization of these polymers and subsequent solvent production, the genes for two new glycoside hydrolases, celA and celD from the fungus Neocallimastix patriciarum, were cloned separately into C. beijerinckii. To do this, a secretion vector based on the pMTL500E shuttle vector and containing the promoter and signal sequence coding region of the Clostridium saccharobutylicum NCP262 eglA gene was constructed and fused either to the celA gene or the celD gene. Stable C. beijerinckii transformants were obtained with the resulting plasmids, pWUR3 (celA) and pWUR4 (celD). The recombinant strains showed clear halos on agar plates containing carboxymethyl cellulose upon staining with Congo red. In addition, their culture supernatants had significant endoglucanase activities (123 U/mg of protein for transformants harboring celA and 78 U/mg of protein for transformants harboring celD). Although C. beijerinckii harboring either celA or celD was not able to grow, separately or in mixed culture, on carboxymethyl cellulose or microcrystalline cellulose, both transformants showed a significant increase in solvent production during growth on lichenan and more extensive degradation of this polymer than that exhibited by the wild-type strain. PMID:11679336

  19. Clostridium beijerinckii cells expressing Neocallimastix patriciarum glycoside hydrolases show enhanced lichenan utilization and solvent production.

    PubMed

    López-Contreras, A M; Smidt, H; van der Oost, J; Claassen, P A; Mooibroek, H; de Vos, W M

    2001-11-01

    Growth and the production of acetone, butanol, and ethanol by Clostridium beijerinckii NCIMB 8052 on several polysaccharides and sugars were analyzed. On crystalline cellulose, growth and solvent production were observed only when a mixture of fungal cellulases was added to the medium. On lichenan growth and solvent production occurred, but this polymer was only partially utilized. To increase utilization of these polymers and subsequent solvent production, the genes for two new glycoside hydrolases, celA and celD from the fungus Neocallimastix patriciarum, were cloned separately into C. beijerinckii. To do this, a secretion vector based on the pMTL500E shuttle vector and containing the promoter and signal sequence coding region of the Clostridium saccharobutylicum NCP262 eglA gene was constructed and fused either to the celA gene or the celD gene. Stable C. beijerinckii transformants were obtained with the resulting plasmids, pWUR3 (celA) and pWUR4 (celD). The recombinant strains showed clear halos on agar plates containing carboxymethyl cellulose upon staining with Congo red. In addition, their culture supernatants had significant endoglucanase activities (123 U/mg of protein for transformants harboring celA and 78 U/mg of protein for transformants harboring celD). Although C. beijerinckii harboring either celA or celD was not able to grow, separately or in mixed culture, on carboxymethyl cellulose or microcrystalline cellulose, both transformants showed a significant increase in solvent production during growth on lichenan and more extensive degradation of this polymer than that exhibited by the wild-type strain. PMID:11679336

  20. Cure Rates in Small Cell and Non-Small Cell Carcinoma of the Lung Utilizing High-Dose Radiotherapy and Chemotherapy

    PubMed Central

    Akbiyik, Nejat; Alexander, Leslie L.

    1986-01-01

    From 1967 to 1977, 72 patients with small cell carcinoma of the lung were seen. Thirty-five of these patients had unilaterally localized lesions (limited disease) and were treated with cobalt 60 radiation therapy (6,000 rad in six weeks) followed by chemotherapy consisting of cyclophosphamide (Cytoxan), vincristine, methotrexate and lomustine (CCNU) (Group A). The remaining 37 patients with extensive disease were treated with similar chemotherapy alone, or in combination with local palliative radiotherapy to the symptomatic area (Group B). For Group A the five-year survival rate was 20 percent, while for both groups combined, it was only 5 percent. During this same period 560 patients with non-small cell carcinomas were treated. The five-year survival rate for those patients with operable, resectable lesions was 33 percent, while for those with unilateral, inoperable, unresectable lesions, it was 10 percent. Thus, it would appear that the results in limited small cell and non-small cell carcinomas of the lung utilizing high-dose radiotherapy followed by chemotherapy are comparable, and that limited small cell carcinoma of the lung patients with high-dose radiotherapy followed by chemotherapy can survive longer than those patients with stage III, non-small cell lung carcinoma. While the two- to five-year survival rates in small cell carcinoma demonstrate no appreciable differences, in non-small cell carcinomas there are significant two- to five-year survival differences. These improved results probably are due to the increased sensitivity of small cell carcinoma to high-dose local radiotherapy and to the chemotherapeutic vulnerability of circulating and microscopic metastatic cancer cells. PMID:3012100

  1. BdCESA7, BdCESA8, and BdPMT Utility Promoter Constructs for Targeted Expression to Secondary Cell-Wall-Forming Cells of Grasses

    PubMed Central

    Petrik, Deborah L.; Cass, Cynthia L.; Padmakshan, Dharshana; Foster, Cliff E.; Vogel, John P.; Karlen, Steven D.; Ralph, John; Sedbrook, John C.

    2016-01-01

    Utility vectors with promoters that confer desired spatial and temporal expression patterns are useful tools for studying gene and cellular function and for industrial applications. To target the expression of DNA sequences of interest to cells forming plant secondary cell walls, which generate most of the vegetative biomass, upstream regulatory sequences of the Brachypodium distachyon lignin biosynthetic gene BdPMT and the cellulose synthase genes BdCESA7 and BdCESA8 were isolated and cloned into binary vectors designed for Agrobacterium-mediated transformation of monocots. Expression patterns were assessed using the β-glucuronidase gene GUSPlus and X-glucuronide staining. All three promoters showed strong expression levels in stem tissue at the base of internodes where cell wall deposition is most active, in both vascular bundle xylem vessels and tracheids, and in interfascicular tissues, with expression less pronounced in developmentally older tissues. In leaves, BdCESA7 and BdCESA8 promoter-driven expression was strongest in leaf veins, leaf margins, and trichomes; relatively weaker and patchy expression was observed in the epidermis. BdPMT promoter-driven expression was similar to the BdCESA promoters expression patterns, including strong expression in trichomes. The intensity and extent of GUS staining varied considerably between transgenic lines, suggesting that positional effects influenced promoter activity. Introducing the BdPMT and BdCESA8 Open Reading Frames into BdPMT and BdCESA8 utility promoter binary vectors, respectively, and transforming those constructs into Brachypodium pmt and cesa8 loss-of-function mutants resulted in rescue of the corresponding mutant phenotypes. This work therefore validates the functionality of these utility promoter binary vectors for use in Brachypodium and likely other grass species. The identification, in Bdcesa8-1 T-DNA mutant stems, of an 80% reduction in crystalline cellulose levels confirms that the BdCESA8 gene is

  2. Solar cells utilizing pulsed-energy crystallized microcrystalline/polycrystalline silicon

    DOEpatents

    Kaschmitter, James L.; Sigmon, Thomas W.

    1995-01-01

    A process for producing multi-terminal devices such as solar cells wherein a pulsed high energy source is used to melt and crystallize amorphous silicon deposited on a substrate which is intolerant to high processing temperatures, whereby to amorphous silicon is converted into a microcrystalline/polycrystalline phase. Dopant and hydrogenization can be added during the fabrication process which provides for fabrication of extremely planar, ultra shallow contacts which results in reduction of non-current collecting contact volume. The use of the pulsed energy beams results in the ability to fabricate high efficiency microcrystalline/polycrystalline solar cells on the so-called low-temperature, inexpensive plastic substrates which are intolerant to high processing temperatures.

  3. Low-cost, high-efficiency solar cells utilizing GaAs-on-Si technology

    SciTech Connect

    Vernon, S.M. )

    1993-04-01

    This report describes work to develop technology to deposit GaAs on Si using a nucleation layer of atomic-layer-epitaxy-grown GaAs or AlAs on Si. This ensures two-dimensional nucleation and should lead to fewer defects in the final GaAs layer. As an alternative, we also developed technology for depositing GaAs on sawtooth-patterned Si. Preliminary studies showed that this material can have a very low defect density, [approximately] 1 [times] 10[sup 5] cm[sup [minus]5], as opposed to our conventionally grown GaAs on SL which has a typical defect density of over 1 [times]10[sup 7] cm[sup [minus]2]. Using these two now methods of GaAs-on-Si material growth, we made solar cells that are expected to show higher efficiencies than those of previous cells.

  4. Utility of Magnetic Cell Separation as a Molecular Sperm Preparation Technique

    PubMed Central

    Said, Tamer M.; Agarwal, Ashok; Zborowski, Maciej; Grunewald, Sonja; Glander, Hans-Juergen; Paasch, Uwe

    2009-01-01

    Assisted reproductive techniques (ART) have become the treatment of choice in many cases of infertility; however the current success rates of these procedures remain suboptimal. Programmed cell death (apoptosis) most likely contributes to failed ART and to the decrease in sperm quality after cryopreservation. There is likelihood that some sperm selected for ART will display features of apoptosis despite their normal appearance, which may be partially responsible for the low fertilization and implantation rates seen with ART. One of the features of apoptosis is the externalization of phosphatidylserine (PS) residues, which are normally present on the inner leaflet of the sperm plasma membrane. Colloidal super-paramagnetic microbeads (~50 nm in diameter) conjugated with annexin-V bind to PS are used to separate dead and apoptotic spermatozoa by magnetic cell sorting (MACS). Cells with externalized PS will bind to these microbeads, while non-apoptotic cells with intact membranes do not bind and could be used during ART. We have conducted a series of experiments to investigate if the MACS technology could be used to improve ART outcomes. Our results clearly indicate that integrating MACS as a part of sperm preparation techniques will improve semen quality and cryosurvival rates by eliminating apoptotic sperm. Non-apoptotic spermatozoa prepared by MACS display higher quality in terms of routine sperm parameters and apoptosis markers. The higher sperm quality is represented by an increased oocyte penetration potential and cryosurvival rates. Thus, the selection of non-apoptotic spermatozoa by MACS should be considered to enhance ART success rates. PMID:18077822

  5. High Fuel Utilization in Solid Oxide Fuel Cells: Experimental Characterization and Data Analysis with Continuous Wavelet Transform

    NASA Astrophysics Data System (ADS)

    Esposito, Angelo; Russo, Luigi; Kändler, Christoph; Pianese, Cesare; Ludwig, Bastian; Steiner, Nadia Yousfi

    2016-06-01

    The on-line diagnostics of Solid Oxide Fuel Cells (SOFCs) is a critical tool to achieve optimal performance and extend the lifetime. The Continuous Wavelet Transform (CWT) methodology was applied to the SOFC voltage signal to detect signatures that reveal the presence of a fault in the cell/stack. The selected fault was anode re-oxidation caused by high Fuel Utilization (FU) (higher then nominal). To experimentally emulate the high FU faults, a standard test procedure was developed, which was used to characterize a μ-CHP system at high FU operation. To complete the analysis, data collected on Single Cells were exploited too. The CWT was applied to the voltage signal for each FU level to verify the qualitative difference (signature) between the signals at different FU's within the same tests as well as the correspondence between the same conditions over different tests. A statistical study was performed to quantify the observed differences and to determine the correspondence between CWT coefficients and operating conditions. The approach proves to be suitable to diagnose high FU in SOFC, showing a successful detection rate above 76%. The results show the good potential of using the CWT methodology as diagnostic tools for SOFCs from cell to stack level.

  6. On-chip fabrication of alkali-metal vapor cells utilizing an alkali-metal source tablet

    NASA Astrophysics Data System (ADS)

    Tsujimoto, K.; Ban, K.; Hirai, Y.; Sugano, K.; Tsuchiya, T.; Mizutani, N.; Tabata, O.

    2013-11-01

    We describe a novel on-chip microfabrication technique for the alkali-metal vapor cell of an optically pumped atomic magnetometer (OPAM), utilizing an alkali-metal source tablet (AMST). The newly proposed AMST is a millimeter-sized piece of porous alumina whose considerable surface area holds deposited alkali-metal chloride (KCl) and barium azide (BaN6), source materials that effectively produce alkali-metal vapor at less than 400 °C. Our experiments indicated that the most effective pore size of the AMST is between 60 and 170 µm. The thickness of an insulating glass spacer holding the AMST was designed to confine generated alkali metal to the interior of the vapor cell during its production, and an integrated silicon heater was designed to seal the device using a glass frit, melted at an optimum temperature range of 460-490 °C that was determined by finite element method thermal simulation. The proposed design and AMST were used to successfully fabricate a K cell that was then operated as an OPAM with a measured sensitivity of 50 pT. These results demonstrate that the proposed concept for on-chip microfabrication of alkali-metal vapor cells may lead to effective replacement of conventional glassworking approaches.

  7. Tissue engineered pre-vascularized buccal mucosa equivalents utilizing a primary triculture of epithelial cells, endothelial cells and fibroblasts.

    PubMed

    Heller, M; Frerick-Ochs, E V; Bauer, H-K; Schiegnitz, E; Flesch, D; Brieger, J; Stein, R; Al-Nawas, B; Brochhausen, C; Thüroff, J W; Unger, R E; Brenner, W

    2016-01-01

    Artificial generated buccal mucosa equivalents are a promising approach for the reconstruction of urethral defects. Limiting in this approach is a poor blood vessel supply after transplantation, resulting in increased morbidity and necrosis. We generated a pre-vascularized buccal mucosa equivalent in a tri-culture of primary buccal epithelial cells, fibroblasts and microvascular endothelial cells, using a native collagen membrane as a scaffold. A successful pre-vascularization and dense formation of capillary-like structures at superficial areas was demonstrated. The lumen size of pre-formed blood vessels corresponded to the capillary size in vivo (10-30 μm). Comparing native with a highly cross-linked collagen membrane we found a distinct higher formation of capillary-like structures on the native membrane, apparently caused by higher secretion of angiogenic factors such as PDGF, IL-8 and angiopoietin by the cells. These capillary-like structures became functional blood vessels through anastomosis with the host vasculature after implantation in nude mice. This in vitro method should result in an accelerated blood supply to the biomaterial with cells after transplantation and increase the succes rates of the implant material. PMID:26606446

  8. A novel micronucleus in vitro assay utilizing human hematopoietic stem cells.

    PubMed

    Kotova, N; Hebert, N; Härnwall, E-L; Vare, D; Mazurier, C; Douay, L; Jenssen, D; Grawé, J

    2015-10-01

    The induction of micronucleated reticulocytes in the bone marrow is a sensitive indicator of chromosomal damage. Therefore, the micronucleus assay in rodents is widely used in genotoxicity and carcinogenicity testing. A test system based on cultured human primary cells could potentially provide better prediction compared to animal tests, increasing patient safety while also implementing the 3Rs principle, i.e. replace, reduce and refine. Hereby, we describe the development of an in vitro micronucleus assay based on animal-free ex vivo culture of human red blood cells from hematopoietic stem cells. To validate the method, five clastogens with direct action, three clastogens requiring metabolic activation, four aneugenic and three non-genotoxic compounds have been tested. Also, different metabolic systems have been applied. Flow cytometry was used for detection and enumeration of micronuclei. Altogether, the results were in agreement with the published data and indicated that a sensitive and cost effective in vitro assay to assess genotoxicity with a potential to high-throughput screening has been developed. PMID:26208286

  9. Utilization of methanol for polymer electrolyte fuel cells in mobile systems

    NASA Astrophysics Data System (ADS)

    Schmidt, V. M.; Brockerhoff, P.; Hohlein, B.; Menzer, R.; Stimming, U.

    1994-04-01

    The constantly growing volume of road traffic requires the introduction of new vehicle propulsion systems with higher efficiency and drastically reduced emission rates. As part of the fuel cell programme of the Research Centre Julich a vehicle propulsion system with methanol as secondary energy carrier and a polymer electrolyte membrane fuel cell (PEMFC) as the main component for energy conversion is developed. The fuel gas is produced by a heterogeneously catalyzed steam reforming reaction in which methanol is converted to H2, CO and CO2. The required energy is provided by the catalytic conversion of methanol for both heating up the system and reforming methanol. The high CO content of the fuel gas requires further processing of the gas or the development of new electrocatalysts for the anode. Various Pt-Ru alloys show promising behaviour as CO-tolerant anodes. The entire fuel cell system is discussed in terms of energy and emission balances. The development of important components is described and experimental results are discussed.

  10. Functional Genomics Screening Utilizing Mutant Mouse Embryonic Stem Cells Identifies Novel Radiation-Response Genes

    PubMed Central

    Loesch, Kimberly; Galaviz, Stacy; Hamoui, Zaher; Clanton, Ryan; Akabani, Gamal; Deveau, Michael; DeJesus, Michael; Ioerger, Thomas; Sacchettini, James C.; Wallis, Deeann

    2015-01-01

    Elucidating the genetic determinants of radiation response is crucial to optimizing and individualizing radiotherapy for cancer patients. In order to identify genes that are involved in enhanced sensitivity or resistance to radiation, a library of stable mutant murine embryonic stem cells (ESCs), each with a defined mutation, was screened for cell viability and gene expression in response to radiation exposure. We focused on a cancer-relevant subset of over 500 mutant ESC lines. We identified 13 genes; 7 genes that have been previously implicated in radiation response and 6 other genes that have never been implicated in radiation response. After screening, proteomic analysis showed enrichment for genes involved in cellular component disassembly (e.g. Dstn and Pex14) and regulation of growth (e.g. Adnp2, Epc1, and Ing4). Overall, the best targets with the highest potential for sensitizing cancer cells to radiation were Dstn and Map2k6, and the best targets for enhancing resistance to radiation were Iqgap and Vcan. Hence, we provide compelling evidence that screening mutant ESCs is a powerful approach to identify genes that alter radiation response. Ultimately, this knowledge can be used to define genetic variants or therapeutic targets that will enhance clinical therapy. PMID:25853515

  11. Utilization of fuel cells to beneficially use coal mine methane. Final report

    SciTech Connect

    Brown, J.T.; O`Brien, D.G.; Miller, A.R.; Atkins, R.; Sanders, M.

    1996-03-01

    DOE has been given the responsibility to encourage industry to recover and use methane that is currently being released to the atmosphere. At this time the only method being employed at the Left Fork Mine to remove methane is the mine ventilation system. The methane content was measured at one one-hundredth of a percent. To prevent this methane from being vented to the atmosphere, degasification wells are proposed. To use the coal mine methane, it is proposed to use phosphoric-acid fuel cells to convert methane to electric power. These fuel cells contain (1) a steam reformer to convert the methane to hydrogen (and carbon dioxide), (2) the fuel cell stack, and (3) a power conditioner that provides 200 kW of 60 Hz alternating current output. The environmental impacts and benefits of using this technology ware summarized in the report. The study indicates the methane emission reduction that could be achieved on a national and Global level. The important point being that this technology is economically viable as is demonstrated in the report.

  12. Technical Advance: Transcription factor, promoter, and enhancer utilization in human myeloid cells

    PubMed Central

    Joshi, Anagha; Pooley, Christopher; Freeman, Tom C.; Lennartsson, Andreas; Babina, Magda; Schmidl, Christian; Geijtenbeek, Teunis; Michoel, Tom; Severin, Jessica; Itoh, Masayoshi; Lassmann, Timo; Kawaji, Hideya; Hayashizaki, Yoshihide; Carninci, Piero; Forrest, Alistair R. R.; Rehli, Michael; Hume, David A.

    2015-01-01

    The generation of myeloid cells from their progenitors is regulated at the level of transcription by combinatorial control of key transcription factors influencing cell-fate choice. To unravel the global dynamics of this process at the transcript level, we generated transcription profiles for 91 human cell types of myeloid origin by use of CAGE profiling. The CAGE sequencing of these samples has allowed us to investigate diverse aspects of transcription control during myelopoiesis, such as identification of novel transcription factors, miRNAs, and noncoding RNAs specific to the myeloid lineage. We further reconstructed a transcription regulatory network by clustering coexpressed transcripts and associating them with enriched cis-regulatory motifs. With the use of the bidirectional expression as a proxy for enhancers, we predicted over 2000 novel enhancers, including an enhancer 38 kb downstream of IRF8 and an intronic enhancer in the KIT gene locus. Finally, we highlighted relevance of these data to dissect transcription dynamics during progressive maturation of granulocyte precursors. A multifaceted analysis of the myeloid transcriptome is made available (www.myeloidome.roslin.ed.ac.uk). This high-quality dataset provides a powerful resource to study transcriptional regulation during myelopoiesis and to infer the likely functions of unannotated genes in human innate immunity. PMID:25717144

  13. Utilizing Energy Transfer in Binary and Ternary Bulk Heterojunction Organic Solar Cells.

    PubMed

    Feron, Krishna; Cave, James M; Thameel, Mahir N; O'Sullivan, Connor; Kroon, Renee; Andersson, Mats R; Zhou, Xiaojing; Fell, Christopher J; Belcher, Warwick J; Walker, Alison B; Dastoor, Paul C

    2016-08-17

    Energy transfer has been identified as an important process in ternary organic solar cells. Here, we develop kinetic Monte Carlo (KMC) models to assess the impact of energy transfer in ternary and binary bulk heterojunction systems. We used fluorescence and absorption spectroscopy to determine the energy disorder and Förster radii for poly(3-hexylthiophene-2,5-diyl), [6,6]-phenyl-C61-butyric acid methyl ester, 4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl]squaraine (DIBSq), and poly(2,5-thiophene-alt-4,9-bis(2-hexyldecyl)-4,9-dihydrodithieno[3,2-c:3',2'-h][1,5]naphthyridine-5,10-dione). Heterogeneous energy transfer is found to be crucial in the exciton dissociation process of both binary and ternary organic semiconductor systems. Circumstances favoring energy transfer across interfaces allow relaxation of the electronic energy level requirements, meaning that a cascade structure is not required for efficient ternary organic solar cells. We explain how energy transfer can be exploited to eliminate additional energy losses in ternary bulk heterojunction solar cells, thus increasing their open-circuit voltage without loss in short-circuit current. In particular, we show that it is important that the DIBSq is located at the electron donor-acceptor interface; otherwise charge carriers will be trapped in the DIBSq domain or excitons in the DIBSq domains will not be able to dissociate efficiently at an interface. KMC modeling shows that only small amounts of DIBSq (<5% by weight) are needed to achieve substantial performance improvements due to long-range energy transfer. PMID:27456294

  14. Benefits of utilizing CellProfiler as a characterization tool for U–10Mo nuclear fuel

    SciTech Connect

    Collette, R.; Douglas, J.; Patterson, L.; Bahun, G.; King, J.; Keiser, D.; Schulthess, J.

    2015-07-15

    Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium–molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellular measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries. - Graphical abstract: Display Omitted - Highlights: • A technique is developed to score U–10Mo FIB-SEM image quality using CellProfiler. • The pass/fail metric is based on image illumination, focus, and area scratched. • Automated image analysis is performed in pipeline fashion to characterize images. • Fission gas void, interaction layer, and grain boundary coverage data is extracted. • Preliminary characterization results demonstrate consistency of the algorithm.

  15. Phase III Advanced Anodes and Cathodes Utilized in Energy Efficient Aluminum Production Cells

    SciTech Connect

    R.A. Christini; R.K. Dawless; S.P. Ray; D.A. Weirauch, Jr.

    2001-11-05

    During Phase I of the present program, Alcoa developed a commercial cell concept that has been estimated to save 30% of the energy required for aluminum smelting. Phase ii involved the construction of a pilot facility and operation of two pilots. Phase iii of the Advanced Anodes and Cathodes Program was aimed at bench experiments to permit the resolution of certain questions to be followed by three pilot cells. All of the milestones related to materials, in particular metal purity, were attained with distinct improvements over work in previous phases of the program. NiO additions to the ceramic phase and Ag additions to the Cu metal phase of the cermet improved corrosion resistance sufficiently that the bench scale pencil anodes met the purity milestones. Some excellent metal purity results have been obtained with anodes of the following composition: Further improvements in anode material composition appear to be dependent on a better understanding of oxide solubilities in molten cryolite. For that reason, work was commissioned with an outside consultant to model the MeO - cryolite systems. That work has led to a better understanding of which oxides can be used to substitute into the NiO-Fe2O3 ceramic phase to stabilize the ferrites and reduce their solubility in molten cryolite. An extensive number of vertical plate bench electrolysis cells were run to try to find conditions where high current efficiencies could be attained. TiB2-G plates were very inconsistent and led to poor wetting and drainage. Pure TiB2 did produce good current efficiencies at small overlaps (shadowing) between the anodes and cathodes. This bench work with vertical plate anodes and cathodes reinforced the importance of good cathode wetting to attain high current efficiencies. Because of those conclusions, new wetting work was commissioned and became a major component of the research during the third year of Phase III. While significant progress was made in several areas, much work needs to be

  16. Benefits of utilizing CellProfiler as a characterization tool for U-10Mo nuclear fuel

    SciTech Connect

    Collette, R.; Douglas, J.; Patterson, L.; Bahun, G.; King, J.; Keiser, D.; Schulthess, J.

    2015-05-01

    Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium-molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellular measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries.

  17. Benefits of utilizing CellProfiler as a characterization tool for U-10Mo nuclear fuel

    DOE PAGESBeta

    Collette, R.; Douglas, J.; Patterson, L.; Bahun, G.; King, J.; Keiser, D.; Schulthess, J.

    2015-05-01

    Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium-molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellularmore » measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries.« less

  18. Enhanced conversion efficiency in perovskite solar cells by effectively utilizing near infrared light.

    PubMed

    Que, Meidan; Que, Wenxiu; Yin, Xingtian; Chen, Peng; Yang, Yawei; Hu, Jiaxing; Yu, Boyan; Du, Yaping

    2016-08-14

    Up-conversion β-NaYF4:Yb(3+),Tm(3+)/NaYF4 core-shell nanoparticles (NYF NPs) with a high luminous intensity in the visible light region were synthesized by a hydrothermal reaction process. Photocurrent densities of the mesoscopic perovskite solar cells fabricated by incorporating up-conversion NYF NPs into the electron transporting layer are effectively enhanced. The effects of the thicknesses of the electron transporting layer and the weight ratio of up-conversion NYF NPs/TiO2 on the power conversion efficiency (PCE) of the as-fabricated devices were also investigated. The results indicate that the PCE of the optimized device achieves 16.9%, which is 20% higher than that of the device without introducing NYF NPs, and the steady-state PCE of the as-fabricated devices is close to its transient-state PCE. The up-conversion effect of NYF NPs is conducive to higher device performance rather than the nanoparticles as scattering centers to increase possible light absorption of the perovskite film or the electronic effect of the NaYF4 shell surface. These results can be further confirmed by finite-difference time-domain simulation. Photoluminescence results suggest that the multiphonon-assistance can accelerate the nonradiative recombination process at a lower temperature. Incorporating NYF NPs into the electron transporting layer opens a new approach to a promising family of electron transporting materials for mesoscopic perovskite solar cells. PMID:27406678

  19. Immunocytochemistry and Image Analysis of Beta-Catenin Redistribution in Normal Human Colon Cell Cultures Treated with Disinfection By-Products.

    EPA Science Inventory

    Epidemiological studies have shown an association between the consumption of chlorinated drinking water and increased risk for colon cancer. In vivo studies proved that rodents exposed to chlorination disinfection byproducts (DBPs) developed aberrant crypt foci (ACF) in t...

  20. Effect of lonidamine on the utilization of /sup 14/C-labeled glucose by human astrocytoma cells

    SciTech Connect

    Paggi, M.G.; Zupi, G.; Fanciulli, M.; Del Carlo, C.; Giorno, S.; Laudonio, N.; Silvestrini, B.; Caputo, A.; Floridi, A.

    1987-10-01

    The effect of lonidamine (LND), 1-(2,4-dichlorobenzyl)-1H-indazol-3 carboxylic acid, on the utilization of carbon from /sup 14/C-labeled glucose by cell cultures of the permanent strain LI derived from a human glioblastoma multiforme (astrocytoma) has been investigated. The results may be summarized as follows. Aerobic glycolysis is the main energy-yielding process as shown by the fact that the greatest part of glucose carbon atoms is incorporated into lactate. Nevertheless, the amount of glucose converted accounts for only 63% of the lactate produced, indicating the presence of an elevated endogenous aerobic glycolysis. The amount of glucose carbon atoms incorporated into CO/sub 2/, lipids, nucleic acid, and supporting structures is low. LND decreased the incorporation of /sup 14/C activity in all the above mentioned isolated compounds because of its ability to inhibit glucose phosphorylation. Consequently, there is a lower concentration of glucose-6-phosphate which, in turn, affects the rate of formation of several metabolites in glycolytic and pentose phosphate pathways. Experiments with (1-/sup 14/C)-2-deoxy-D-glucose further substantiate the idea of glucose phosphorylation as a main target of LND and strongly suggest the presence of a mitochondrially bound hexokinase. The higher inhibition of glucose phosphorylation in exponentially growing cells indicates a further shift of the enzyme toward mitochondria-bound form and confirms the importance of the energy status of the cell in eliciting the response to LND. The reduced capacity of LND-treated cells to synthetize ATP and glucose-6-phosphate reflects the decreased synthesis of proteins and nucleic acids, which affects cell growth and duplication.

  1. Platform for a Hydrocarbon Exhaust Gas Sensor Utilizing a Pumping Cell and a Conductometric Sensor

    PubMed Central

    Biskupski, Diana; Geupel, Andrea; Wiesner, Kerstin; Fleischer, Maximilian; Moos, Ralf

    2009-01-01

    Very often, high-temperature operated gas sensors are cross-sensitive to oxygen and/or they cannot be operated in oxygen-deficient (rich) atmospheres. For instance, some metal oxides like Ga2O3 or doped SrTiO3 are excellent materials for conductometric hydrocarbon detection in the rough atmosphere of automotive exhausts, but have to be operated preferably at a constant oxygen concentration. We propose a modular sensor platform that combines a conductometric two-sensor-setup with an electrochemical pumping cell made of YSZ to establish a constant oxygen concentration in the ambient of the conductometric sensor film. In this paper, the platform is introduced, the two-sensor-setup is integrated into this new design, and sensing performance is characterized. Such a platform can be used for other sensor principles as well. PMID:22423212

  2. Tandem repeat knockout utilizing the CRISPR/Cas9 system in human cells.

    PubMed

    Lv, Qingyan; Lai, Liangxue; Yuan, Lin; Song, Yuning; Sui, Tingting; Li, Zhanjun

    2016-05-15

    Tandem repeats have been shown to cause human genetic diseases and contribute significantly to genome variation and instability. Although multi-sgRNAs mediated CRISPR/Cas9 system have used to generate regional deletions previously, in this study we explored a method of generating regional deletions of tandem repeats by taking advantage of the off-target effects of CRISPR/Cas9 in 293FT cells. Our results revealed that generation of large-fragment deletions of tandem repeats located in the MAGEL2 and XIST gene was possible. In summary, we have demonstrated that large-fragment deletions of tandem repeats can be achieved using a sgRNA-directed CRISPR/Cas9 system, facilitating the functional study of tandem repeats in future studies. PMID:26873114

  3. Thylakoid direct photobioelectrocatalysis: utilizing stroma thylakoids to improve bio-solar cell performance.

    PubMed

    Rasmussen, Michelle; Minteer, Shelley D

    2014-08-28

    Thylakoid membranes from spinach were separated into grana and stroma thylakoid fractions which were characterized by several methods (pigment content, protein gel electrophoresis, photosystem activities, and electron microscopy analysis) to confirm that the intact thylakoids were differentiated into the two domains. The results of photoelectrochemical experiments showed that stroma thylakoid electrodes generate photocurrents more than four times larger than grana thylakoids (51 ± 4 nA cm(-2) compared to 11 ± 1 nA cm(-2)). A similar trend was seen in a bio-solar cell configuration with stroma thylakoids giving almost twice the current (19 ± 3 μA cm(-2)) as grana thylakoids (11 ± 2 μA cm(-2)) with no change in open circuit voltage. PMID:25019197

  4. Platform for a hydrocarbon exhaust gas sensor utilizing a pumping cell and a conductometric sensor.

    PubMed

    Biskupski, Diana; Geupel, Andrea; Wiesner, Kerstin; Fleischer, Maximilian; Moos, Ralf

    2009-01-01

    Very often, high-temperature operated gas sensors are cross-sensitive to oxygen and/or they cannot be operated in oxygen-deficient (rich) atmospheres. For instance, some metal oxides like Ga(2)O(3) or doped SrTiO(3) are excellent materials for conductometric hydrocarbon detection in the rough atmosphere of automotive exhausts, but have to be operated preferably at a constant oxygen concentration. We propose a modular sensor platform that combines a conductometric two-sensor-setup with an electrochemical pumping cell made of YSZ to establish a constant oxygen concentration in the ambient of the conductometric sensor film. In this paper, the platform is introduced, the two-sensor-setup is integrated into this new design, and sensing performance is characterized. Such a platform can be used for other sensor principles as well. PMID:22423212

  5. The management of metastatic germ cell tumours and the clinical utility of lactate dehydrogenase estimations.

    PubMed

    Gill, P G; Abbott, R; Jones, A M; Thomas, D W

    1985-04-01

    Forty-five patients with metastatic germ cell tumour were treated with chemotherapy. Complete remission was achieved in 63% of all cases and in 65% of patients whose primary tumour arose in the testis or ovary. Surgical resection of abdominal masses persisting after chemotherapy was performed in seven patients, two of whom were found to have persistent tumours. Twenty-seven of the 33 patients with teratoma originating in the gonads remain in complete remission. Total serum LDH activity was elevated in 28 of the patients with measurable disease. The increased LDH was not accompanied by significant alteration in other hepatic enzymes nor were hepatic metastases demonstrable in these patients. Fractionation of the LDH demonstrated that the increased LDH in these patients was located in either iso-enzymes 1 or fractions 1 + 2. Alteration of the serum LDH activity correlated with the response to therapy and warrants further study. PMID:2412541

  6. Enhanced conversion efficiency in perovskite solar cells by effectively utilizing near infrared light

    NASA Astrophysics Data System (ADS)

    Que, Meidan; Que, Wenxiu; Yin, Xingtian; Chen, Peng; Yang, Yawei; Hu, Jiaxing; Yu, Boyan; Du, Yaping

    2016-07-01

    Up-conversion β-NaYF4:Yb3+,Tm3+/NaYF4 core-shell nanoparticles (NYF NPs) with a high luminous intensity in the visible light region were synthesized by a hydrothermal reaction process. Photocurrent densities of the mesoscopic perovskite solar cells fabricated by incorporating up-conversion NYF NPs into the electron transporting layer are effectively enhanced. The effects of the thicknesses of the electron transporting layer and the weight ratio of up-conversion NYF NPs/TiO2 on the power conversion efficiency (PCE) of the as-fabricated devices were also investigated. The results indicate that the PCE of the optimized device achieves 16.9%, which is 20% higher than that of the device without introducing NYF NPs, and the steady-state PCE of the as-fabricated devices is close to its transient-state PCE. The up-conversion effect of NYF NPs is conducive to higher device performance rather than the nanoparticles as scattering centers to increase possible light absorption of the perovskite film or the electronic effect of the NaYF4 shell surface. These results can be further confirmed by finite-difference time-domain simulation. Photoluminescence results suggest that the multiphonon-assistance can accelerate the nonradiative recombination process at a lower temperature. Incorporating NYF NPs into the electron transporting layer opens a new approach to a promising family of electron transporting materials for mesoscopic perovskite solar cells.Up-conversion β-NaYF4:Yb3+,Tm3+/NaYF4 core-shell nanoparticles (NYF NPs) with a high luminous intensity in the visible light region were synthesized by a hydrothermal reaction process. Photocurrent densities of the mesoscopic perovskite solar cells fabricated by incorporating up-conversion NYF NPs into the electron transporting layer are effectively enhanced. The effects of the thicknesses of the electron transporting layer and the weight ratio of up-conversion NYF NPs/TiO2 on the power conversion efficiency (PCE) of the as

  7. Development of a Solid Oxide Fuel Cell for the utilization of coal mine gas

    NASA Astrophysics Data System (ADS)

    Groß, B.; Blum, L.; de Haart, L. G. J.; Dengel, A.

    Apart from natural gas there is another important natural source of methane. The so-called coal mine gas is a by-product of the geochemical process of the carbonization of sediments from marsh woods of the Earth's Carboniferous Period. Methane evaporates from the coal and has to be removed out of the active mines where it represents one of the main safety risks. Methane also evaporates in abandoned coal mines. In the federal state Saarland in Germany exists above ground a more than 110 km pipeline for the drained coal mine gas from 12 different sources. The content of methane varies between 25 and 90%, the oxygen content (from air) is in the range up to 10%. This wide range or variation, respectively, of fuel and oxygen content, causes a lot of problems for the use in conventional engines. Therefore the company Evonik New Energies GmbH is interested in using SOFC with coal mine gas as efficient as possible to produce electric power. For that purpose at Forschungszentrum Jülich the available SOFC technology was adapted to the use with coal mine gas and a test facility was designed to operate an SOFC stack (approximately 2 kW electrical power output) together with a pre-reformer. This paper presents the results of the coal mine gas analysis and the effect on the pre-reformer and the fuel cell. The composition of the coal mine gas was determined by means of micro-gas chromatography. The results obtained from preliminary tests using synthetic and real coal mine gas on the pre-reformer and on the fuel cell are discussed.

  8. Perspectives on utilizing unique features of microfluidics technology for particle and cell sorting

    PubMed Central

    Adams, Jonathan D.; Tom Soh, H.

    2009-01-01

    Sample preparation is often the most tedious and demanding step in an assay, but it also plays an essential role in determining the quality of results. As biological questions and analytical methods become increasingly sophisticated, there is a rapidly growing need for systems that can reliably and reproducibly separate cells and particles with high purity, throughput and recovery. Microfluidics technology represents a compelling approach in this regard, allowing precise control of separation forces for high performance separation in inexpensive, or even disposable, devices. In addition, microfluidics technology enables the fabrication of arrayed and integrated systems that operate either in parallel or in tandem, in a capacity that would be difficult to achieve in macro-scale systems. In this report, we use recent examples from our work to illustrate the potential of microfluidic cell- and particle-sorting devices. We demonstrate the potential of chip-based high-gradient magnetophoresis that enable high-purity separation through reversible trapping of target particles paired with high-stringency washing with minimal loss. We also describe our work in the development of devices that perform simultaneous multi-target sorting, either through precise control of magnetic and fluidic forces or through the integration of multiple actuation forces into a single monolithic device. We believe that such devices may serve as a powerful “front-end” module of highly integrated analytical platforms capable of providing actionable diagnostic information directly from crude, unprocessed samples - the success of such systems may hold the key to advancing point-of-care diagnostics and personalized medicine. PMID:20161387

  9. Three-dimensional matrix fiber alignment modulates cell migration and MT1-MMP utility by spatially and temporally directing protrusions

    NASA Astrophysics Data System (ADS)

    Fraley, Stephanie I.; Wu, Pei-Hsun; He, Lijuan; Feng, Yunfeng; Krisnamurthy, Ranjini; Longmore, Gregory D.; Wirtz, Denis

    2015-10-01

    Multiple attributes of the three-dimensional (3D) extracellular matrix (ECM) have been independently implicated as regulators of cell motility, including pore size, crosslink density, structural organization, and stiffness. However, these parameters cannot be independently varied within a complex 3D ECM protein network. We present an integrated, quantitative study of these parameters across a broad range of complex matrix configurations using self-assembling 3D collagen and show how each parameter relates to the others and to cell motility. Increasing collagen density resulted in a decrease and then an increase in both pore size and fiber alignment, which both correlated significantly with cell motility but not bulk matrix stiffness within the range tested. However, using the crosslinking enzyme Transglutaminase II to alter microstructure independently of density revealed that motility is most significantly predicted by fiber alignment. Cellular protrusion rate, protrusion orientation, speed of migration, and invasion distance showed coupled biphasic responses to increasing collagen density not predicted by 2D models or by stiffness, but instead by fiber alignment. The requirement of matrix metalloproteinase (MMP) activity was also observed to depend on microstructure, and a threshold of MMP utility was identified. Our results suggest that fiber topography guides protrusions and thereby MMP activity and motility.

  10. Three-dimensional matrix fiber alignment modulates cell migration and MT1-MMP utility by spatially and temporally directing protrusions.

    PubMed

    Fraley, Stephanie I; Wu, Pei-Hsun; He, Lijuan; Feng, Yunfeng; Krisnamurthy, Ranjini; Longmore, Gregory D; Wirtz, Denis

    2015-01-01

    Multiple attributes of the three-dimensional (3D) extracellular matrix (ECM) have been independently implicated as regulators of cell motility, including pore size, crosslink density, structural organization, and stiffness. However, these parameters cannot be independently varied within a complex 3D ECM protein network. We present an integrated, quantitative study of these parameters across a broad range of complex matrix configurations using self-assembling 3D collagen and show how each parameter relates to the others and to cell motility. Increasing collagen density resulted in a decrease and then an increase in both pore size and fiber alignment, which both correlated significantly with cell motility but not bulk matrix stiffness within the range tested. However, using the crosslinking enzyme Transglutaminase II to alter microstructure independently of density revealed that motility is most significantly predicted by fiber alignment. Cellular protrusion rate, protrusion orientation, speed of migration, and invasion distance showed coupled biphasic responses to increasing collagen density not predicted by 2D models or by stiffness, but instead by fiber alignment. The requirement of matrix metalloproteinase (MMP) activity was also observed to depend on microstructure, and a threshold of MMP utility was identified. Our results suggest that fiber topography guides protrusions and thereby MMP activity and motility. PMID:26423227

  11. Three-dimensional matrix fiber alignment modulates cell migration and MT1-MMP utility by spatially and temporally directing protrusions

    PubMed Central

    Fraley, Stephanie I.; Wu, Pei-hsun; He, Lijuan; Feng, Yunfeng; Krisnamurthy, Ranjini; Longmore, Gregory D.; Wirtz, Denis

    2015-01-01

    Multiple attributes of the three-dimensional (3D) extracellular matrix (ECM) have been independently implicated as regulators of cell motility, including pore size, crosslink density, structural organization, and stiffness. However, these parameters cannot be independently varied within a complex 3D ECM protein network. We present an integrated, quantitative study of these parameters across a broad range of complex matrix configurations using self-assembling 3D collagen and show how each parameter relates to the others and to cell motility. Increasing collagen density resulted in a decrease and then an increase in both pore size and fiber alignment, which both correlated significantly with cell motility but not bulk matrix stiffness within the range tested. However, using the crosslinking enzyme Transglutaminase II to alter microstructure independently of density revealed that motility is most significantly predicted by fiber alignment. Cellular protrusion rate, protrusion orientation, speed of migration, and invasion distance showed coupled biphasic responses to increasing collagen density not predicted by 2D models or by stiffness, but instead by fiber alignment. The requirement of matrix metalloproteinase (MMP) activity was also observed to depend on microstructure, and a threshold of MMP utility was identified. Our results suggest that fiber topography guides protrusions and thereby MMP activity and motility. PMID:26423227

  12. Strategies for the production of cell wall-deconstructing enzymes in lignocellulosic biomass and their utilization for biofuel production.

    PubMed

    Park, Sang-Hyuck; Ong, Rebecca Garlock; Sticklen, Mariam

    2016-06-01

    Microbial cell wall-deconstructing enzymes are widely used in the food, wine, pulp and paper, textile, and detergent industries and will be heavily utilized by cellulosic biorefineries in the production of fuels and chemicals. Due to their ability to use freely available solar energy, genetically engineered bioenergy crops provide an attractive alternative to microbial bioreactors for the production of cell wall-deconstructing enzymes. This review article summarizes the efforts made within the last decade on the production of cell wall-deconstructing enzymes in planta for use in the deconstruction of lignocellulosic biomass. A number of strategies have been employed to increase enzyme yields and limit negative impacts on plant growth and development including targeting heterologous enzymes into specific subcellular compartments using signal peptides, using tissue-specific or inducible promoters to limit the expression of enzymes to certain portions of the plant or certain times, and fusion of amplification sequences upstream of the coding region to enhance expression. We also summarize methods that have been used to access and maintain activity of plant-generated enzymes when used in conjunction with thermochemical pretreatments for the production of lignocellulosic biofuels. PMID:26627868

  13. Utility of Iron Staining in Identifying the Cause of Renal Allograft Dysfunction in Patients with Sickle Cell Disease.

    PubMed

    Wang, Yingchun; Doshi, Mona; Khan, Salman; Li, Wei; Zhang, Ping L

    2015-01-01

    Sickle cell nephropathy (SCN) is associated with iron/heme deposition in proximal renal tubules and related acute tubular injury (ATI). Here we report the utility of iron staining in differentiating causes of renal allograft dysfunction in patients with a history of sickle cell disease. Case 1: the patient developed acute allograft dysfunction two years after renal transplant. Her renal biopsy showed ATI, supported by patchy loss of brush border and positive staining of kidney injury molecule-1 in proximal tubular epithelial cells, where diffuse increase in iron staining (2+) was present. This indicated that ATI likely resulted from iron/heme toxicity to proximal tubules. Electron microscope confirmed aggregated sickle RBCs in glomeruli, indicating a recurrent SCN. Case 2: four years after renal transplant, the patient developed acute allograft dysfunction and became positive for serum donor-specific antibody. His renal biopsy revealed thrombotic microangiopathy (TMA) and diffuse positive C4d stain in peritubular capillaries. Iron staining was negative in the renal tubules, implying that TMA was likely associated with acute antibody-mediated rejection (AAMR, type 2) rather than recurrent SCN. These case reports imply that iron staining is an inexpensive but effective method in distinguishing SCN-associated renal injury in allograft kidney from other etiologies. PMID:26697257

  14. Performance of vapor-fed direct dimethyl ether fuel cell utilizing high temperature polybenzimidazole polymer electrolyte membrane

    NASA Astrophysics Data System (ADS)

    Neutzler, Jay; Qian, Guoqing; Huang, Kevin; Benicewicz, Brian

    2012-10-01

    There is increasing interest in dimethyl ether (DME) as a synthetic fuel. It has present-day relevance and introduces an effective path forward as an energy-dense, low-pressure hydrogen carrier/storage fuel for fuel cells with applications in transportation, stationary, and portable power. Direct reaction DME fuel cells have particular relevance to portable power. This study presents the performance of the vapor-fed direct reaction of DME using high temperature Polybenzimidazole (PBI) Polymer Electrolyte Membrane (PEM). Catalyzed PBI membrane utilized a Pt/Ru black anode and a Pt/C supported cathode. Performance was evaluated from temperatures of 180 °C-210 °C and at pressures from 100 kPa to 300 kPa. A strong performance correlation was observed in this study for these temperatures and pressures. A peak power density of 50 mW cm-2 was achieved at 180 °C without back pressure, whereas, an increase to 129 mW cm-2 was achieved at 210 °C at 300 kPa pressure. The performance of high temperature PBI PEMFCs with direct vapor-fed DME are investigated with emphasis on the critical variables of cell operation; temperature, back pressure, and humidity.

  15. Utilization of the Generalized Method of Cells to Analyze the Deformation Response of Laminated Ceramic Matrix Composites

    NASA Technical Reports Server (NTRS)

    Goldberg, Robert K.

    2012-01-01

    In order to practically utilize ceramic matrix composites in aircraft engine components, robust analysis tools are required that can simulate the material response in a computationally efficient manner. The MAC/GMC software developed at NASA Glenn Research Center, based on the Generalized Method of Cells micromechanics method, has the potential to meet this need. Utilizing MAC/GMC, the effective stiffness properties, proportional limit stress and ultimate strength can be predicted based on the properties and response of the individual constituents. In this paper, the effective stiffness and strength properties for a representative laminated ceramic matrix composite with a large diameter fiber are predicted for a variety of fiber orientation angles and laminate orientations. As part of the analytical study, methods to determine the in-situ stiffness and strength properties of the constituents required to appropriately simulate the effective composite response are developed. The stiffness properties of the representative composite have been adequately predicted for all of the fiber orientations and laminate configurations examined in this study. The proportional limit stresses and strains and ultimate stresses and strains were predicted with varying levels of accuracy, depending on the laminate orientation. However, for the cases where the predictions did not have the desired level of accuracy, the specific issues related to the micromechanics theory were identified which could lead to difficulties that were encountered that could be addressed in future work.

  16. Heat removal from high temperature tubular solid oxide fuel cells utilizing product gas from coal gasifiers.

    SciTech Connect

    Parkinson, W. J. ,

    2003-01-01

    In this work we describe the results of a computer study used to investigate the practicality of several heat exchanger configurations that could be used to extract heat from tubular solid oxide fuel cells (SOFCs) . Two SOFC feed gas compositions were used in this study. They represent product gases from two different coal gasifier designs from the Zero Emission Coal study at Los Alamos National Laboratory . Both plant designs rely on the efficient use of the heat produced by the SOFCs . Both feed streams are relatively rich in hydrogen with a very small hydrocarbon content . One feed stream has a significant carbon monoxide content with a bit less hydrogen . Since neither stream has a significant hydrocarbon content, the common use of the endothermic reforming reaction to reduce the process heat is not possible for these feed streams . The process, the method, the computer code, and the results are presented as well as a discussion of the pros and cons of each configuration for each process .

  17. Hematopoietic stem and progenitor cell harvesting: technical advances and clinical utility

    PubMed Central

    Hequet, Olivier

    2015-01-01

    Hematopoietic stem and progenitor cell (HSPC) transplantations require prior harvesting of allogeneic or autologous HSPCs. HSPCs are usually present in bone marrow (BM) during the entire life, in cord blood (CB) at birth, or in peripheral blood (PB) under particular circumstances. HSPCs were first harvested in BM and later in CB and PB, as studies showed interesting features of such grafts. All harvesting methods were in use throughout the years, except BM harvesting for HSPC autologous transplantation, which was replaced by PB harvesting. BM, CB, and PB harvesting methods have been developed, and materials and devices technically improved to increase the number of HSPCs harvested. In parallel, knowing the features of the donors or patients associated with successful numbers of HSPCs allows the adaptation of appropriate harvesting methods. Moreover, it is important to ensure the safety of donors or patients while harvesting. This review describes the methods used for harvesting based on recent studies or developments around these methods, and more particularly, the means developed to increase the numbers of HSPCs harvested in each method. It also explains briefly the influence of technical improvements in HSPC harvesting on potential changes in HSPC graft composition. PMID:25733943

  18. The Utility of Allograft Mesenchymal Stem Cells for Spine Fusion: A Literature Review

    PubMed Central

    Lubelski, Daniel; Abdullah, Kalil G.; Benzel, Edward C.; Mroz, Thomas E.

    2012-01-01

    More than 50% of patients complain of postoperative donor site morbidity following iliac crest bone graft harvest, and recent discoveries have identified adverse outcomes following bone morphogenetic protein use in spine fusion. This has led the spine community to turn toward alternative methods to promote fusion following spine surgery. The present article reviews numerous studies that have shown the osteogenic potential of mesenchymal stem cells (MSCs). MSCs have been used with both in vitro and in vivo models and have involved animal studies ranging from rats to macaque monkeys to successfully induce bone regeneration in lesions of the tibia and spine. There is no fear of graft rejection, as there may be with other allograft materials, because neither undifferentiated nor differentiated MSCs elicit lymphocyte response when transplanted; they tend to alter the cytokine profile to an anti-inflammatory state. Early clinical trials are underway with various commercially available MSC formulations. Although there is much enthusiasm, it is integral that the spine surgery community carefully evaluate the use of MSCs in spine fusion through well-designed and executed studies to determine the efficacy and safety profiles in spine surgery patients. PMID:27054055

  19. Response dynamics of phosphorelays suggest their potential utility in cell signalling

    PubMed Central

    Csikász-Nagy, Attila; Cardelli, Luca; Soyer, Orkun S.

    2011-01-01

    Phosphorelays are extended two-component signalling systems found in diverse bacteria, lower eukaryotes and plants. Only few of these systems are characterized, and we still lack a full understanding of their signalling abilities. Here, we aim to achieve a global understanding of phosphorelay signalling and its dynamical properties. We develop a generic model, allowing us to systematically analyse response dynamics under different assumptions. Using this model, we find that the steady-state concentration of phosphorylated protein at the final layer of a phosphorelay is a linearly increasing, but eventually saturating function of the input. In contrast, the intermediate layers can display ultrasensitivity. We find that such ultrasensitivity is a direct result of the phosphorelay biochemistry; shuttling of a single phosphate group from the first to the last layer. The response dynamics of the phosphorelay results in tolerance of cross-talk, especially when it occurs as cross-deactivation. Further, it leads to a high signal-to-noise ratio for the final layer. We find that a relay length of four, which is most commonly observed, acts as a saturating point for these dynamic properties. These findings suggest that phosphorelays could act as a mechanism to reduce noise and effects of cross-talk on the final layer of the relay and enforce its input–response relation to be linear. In addition, our analysis suggests that middle layers of phosphorelays could embed thresholds. We discuss the consequence of these findings in relation to why cells might use phosphorelays along with enzymatic kinase cascades. PMID:20702449

  20. Utility of Red Cell Distribution Width as a Prognostic Factor in Young Breast Cancer Patients

    PubMed Central

    Huang, Du-Ping; Ma, Rui-Min; Xiang, You-Qun

    2016-01-01

    Abstract The prognosis of breast cancer occurs in young women is usually poor. Red cell distribution width (RDW), 1 of many routinely examined parameters, has recently been proposed as a prognostic marker in solid tumors. The aim of our study was to assess the predictive value of RDW for survival in young women with breast cancer. We reviewed 203 consecutive young female patients (under 40) with invasive breast cancer diagnosed at the First Affiliated Hospital of Wenzhou Medical University between January 2008 and December 2012. Preoperational RDW, clinicopathological information, and prognostic data were collected. RDW levels were divided into 2 groups: 161 patients with low RDW (≤13.75%) and 42 patients with high RDW (>13.75%). Clinicopathological differences between the 2 groups were calculated by chi-squared test and Wilcoxon rank-sum test. Kaplan–Meier survival analysis and Cox proportional hazard regression analyses were used to examine the effect of RDW on survival. We found that high RDW was significantly associated with larger tumor size (P = 0.002), positive lymph node metastases (P = 0.011), and advanced stages (P = 0.004). Patients with high RDW showed significantly lower disease-free survival (DFS; P < 0.001) and lower overall survival (OS) rate (P < 0.001) than patients with low RDW. Moreover, the Cox regression multivariate analysis revealed that high pretreatment DRW was independently correlated with poor DFS and OS, with hazard ratio 4.819 (95% confidence interval [CI] 2.291–10.138, P < 0.001) and 5.887 (95% CI 1.666–20.802, P = 0.006), respectively. In conclusion, our study demonstrated that pretreatment RDW may be associated with DFS and OS in young women with breast cancer. Further validation and feasibility studies are required before the result of our study can be considered for clinical practice. PMID:27124030

  1. High-Resolution Microfluidic Single-Cell Transcriptional Profiling Reveals Clinically Relevant Subtypes among Human Stem Cell Populations Commonly Utilized in Cell-Based Therapies

    PubMed Central

    Rennert, Robert C.; Schäfer, Richard; Bliss, Tonya; Januszyk, Michael; Sorkin, Michael; Achrol, Achal S.; Rodrigues, Melanie; Maan, Zeshaan N.; Kluba, Torsten; Steinberg, Gary K.; Gurtner, Geoffrey C.

    2016-01-01

    Stem cell therapies can promote neural repair and regeneration, yet controversy regarding optimal cell source and mechanism of action has slowed clinical translation, potentially due to undefined cellular heterogeneity. Single-cell resolution is needed to identify clinically relevant subpopulations with the highest therapeutic relevance. We combine single-cell microfluidic analysis with advanced computational modeling to study for the first time two common sources for cell-based therapies, human NSCs and MSCs. This methodology has the potential to logically inform cell source decisions for any clinical application. PMID:27047447

  2. BdCESA7, BdCESA8, and BdPMT utility promoter constructs for targeted expression to secondary cell-wall-forming cells of grasses

    DOE PAGESBeta

    Petrik, Deborah L.; Cass, Cynthia L.; Padmakshan, Dharshana; Foster, Cliff E.; Vogel, John P.; Karlen, Steven D.; Ralph, John; Sedbrook, John C.

    2016-02-04

    Utility vectors with promoters that confer desired spatial and temporal expression patterns are useful tools for studying gene and cellular function and for industrial applications. To target the expression of DNA sequences of interest to cells forming plant secondary cell walls, which generate most of the vegetative biomass, upstream regulatory sequences of the Brachypodium distachyon lignin biosynthetic gene BdPMT and the cellulose synthase genes BdCESA7 and BdCESA8 were isolated and cloned into binary vectors designed for Agrobacterium-mediated transformation of monocots. Expression patterns were assessed using the β-glucuronidase gene GUSPlus and X-glucuronide staining. All three promoters showed strong expression levels inmore » stem tissue at the base of internodes where cell wall deposition is most active, in both vascular bundle xylem vessels and tracheids, and in interfascicular tissues, with expression less pronounced in developmentally older tissues. In leaves, BdCESA7 and BdCESA8 promoter-driven expression was strongest in leaf veins, leaf margins, and trichomes; relatively weaker and patchy expression was observed in the epidermis. BdPMT promoter-driven expression was similar to the BdCESA promoters expression patterns, including strong expression in trichomes. The intensity and extent of GUS staining varied considerably between transgenic lines, suggesting that positional effects influenced promoter activity. Introducing the BdPMT and BdCESA8 Open Reading Frames into BdPMT and BdCESA8 utility promoter binary vectors, respectively, and transforming those constructs into Brachypodium pmt and cesa8 loss-of-function mutants resulted in rescue of the corresponding mutant phenotypes. This work therefore validates the functionality of these utility promoter binary vectors for use in Brachypodium and likely other grass species. Lastly, the identification, in Bdcesa8-1 T-DNA mutant stems, of an 80% reduction in crystalline cellulose levels confirms that the

  3. [Yes to research, no to utilization? Medical, pharmacological and toxicological utilization of human embryonic stem cells from an ethical point of view].

    PubMed

    Kress, H

    2008-09-01

    In exceptional cases, the German Stem Cell Act allows research on human embryonic stem cells. However, it does not allow the implementation of the research results if this in turn requires the use of further embryonic stem cell lines. It has, in the meantime, transpired that such research results could be of concrete use. Thus, in the distant future, it could be used in the clinical treatment of patients. Already in the nearer future the use of human embryonic stem cell lines can be envisaged for both the development and testing of medicines as well as in the field of toxicology. To this end, research concerning embryo toxicity and neurotoxicity is ground-breaking. The toxicological and pharmacological use of human embryonic stem cell lines should serve the protection of human health as well as the safe and reliable use of medicines. In addition, animal experiments could be reduced, which is desirable from a point of view of animal protection ethics. Since research on human embryonic stem cell lines is actually permitted in Germany, the use of the respective research results should be allowed all the more. This follows from the basic human right to health protection and health care. Legal ambiguities, which still exist in this respect, should be removed. PMID:18773176

  4. Cytometric comparisons between circulating tumor cells from prostate cancer patients and the prostate tumor derived LNCaP cell line

    PubMed Central

    Lazar, Daniel C.; Cho, Edward H.; Luttgen, Madelyn S.; Metzner, Thomas J.; Uson, Maria Loressa; Torrey, Melissa; Gross, Mitchell E.; Kuhn, Peter

    2012-01-01

    Many important experiments in cancer research are initiated with cell line data analysis due to the ease of accessibility and utilization. Recently, the ability to capture and characterize circulating tumor cells (CTCs) has become more prevalent in the research setting. This ability to detect, isolate, and analyze CTCs allows us to directly compare specific protein expression levels found in patient CTCs to cell lines. In this study, we use immunocytochemistry to compare the protein expression levels of total cytokeratin (CK) and androgen receptor (AR) in CTCs and cell lines from patients with prostate cancer to determine what translational insights might be gained through the use of cell line data. A non-enrichment CTC detection assay enables us to compare cytometric features and relative expression levels of CK and AR by indirect immunofluorescence from prostate cancer patients against the prostate cancer cell line LNCaP. We measured physical characteristics of these two groups and observed significant differences in cell size, fluorescence intensity, and nuclear to cytoplasmic (N/C) ratio. We hope that these experiments will initiate a foundation to allow cell line data to be compared against characteristics of primary cells from patients. PMID:22306736

  5. Application of a Novel Population of Multipotent Stem Cells Derived from Skin Fibroblasts as Donor Cells in Bovine SCNT

    PubMed Central

    Pan, Shaohui; Chen, Wuju; Liu, Xu; Xiao, Jiajia; Wang, Yanqin; Liu, Jun; Du, Yue; Wang, Yongsheng; Zhang, Yong

    2015-01-01

    Undifferentiated stem cells are better donor cells for somatic cell nuclear transfer (SCNT), resulting in more offspring than more differentiated cells. While various stem cell populations have been confirmed to exist in the skin, progress has been restricted due to the lack of a suitable marker for their prospective isolation. To address this fundamental issue, a marker is required that could unambiguously prove the differentiation state of the donor cells. We therefore utilized magnetic activated cell sorting (MACS) to separate a homogeneous population of small SSEA-4+ cells from a heterogeneous population of bovine embryonic skin fibroblasts (BEF). SSEA-4+ cells were 8-10 μm in diameter and positive for alkaline phosphatase (AP). The percentage of SSEA-4+ cells within the cultured BEF population was low (2-3%). Immunocytochemistry and PCR analyses revealed that SSEA-4+ cells expressed pluripotency-related markers, and could differentiate into cells comprising all three germ layers in vitro. They remained undifferentiated over 20 passages in suspension culture. In addition, cloned embryos derived from SSEA-4 cells showed significant differences in cleavage rate and blastocyst development when compared with those from BEF and SSEA-4− cells. Moreover, blastocysts derived from SSEA-4+ cells showed a higher total cell number and lower apoptotic index as compared to BEF and SSEA-4– derived cells. It is well known that nuclei from pluripotent stem cells yield a higher cloning efficiency than those from adult somatic cells, however, pluripotent stem cells are relatively difficult to obtain from bovine. The SSEA-4+ cells described in the current study provide an attractive candidate for SCNT and a promising platform for the generation of transgenic cattle. PMID:25602959

  6. Utilization of modified surfactant-associated protein B for delivery of DNA to airway cells in culture.

    PubMed Central

    Baatz, J E; Bruno, M D; Ciraolo, P J; Glasser, S W; Stripp, B R; Smyth, K L; Korfhagen, T R

    1994-01-01

    Pulmonary surfactant lines the airway epithelium and creates a potential barrier to successful transfection of the epithelium in vivo. Based on the functional properties of pulmonary surfactant protein B (SP-B) and the fact that this protein is neither toxic nor immunogenic in the airway, we hypothesized that SP-B could be modified to deliver DNA to airway cells. We have modified native bovine SP-B by the covalent linkage of poly(lysine) (average molecular mass of 3.3 or 10 kDa) to the N terminus of SP-B and formed complexes between a test plasmid and the modified SP-B. Transfection efficiency was determined by transfection of pulmonary adenocarcinoma cells (H441) in culture with the test plasmid pCPA-RSV followed by measurement of activity of the reporter gene encoding chloramphenicol acetyltransferase (CAT). Transfections were performed with DNA.protein complexes using poly(lysine)10kDa-SP-B ([Lys]10kDa-SP-B) or poly(lysine)3.3kDa-SP-B ([Lys]3.3kDa-SP-B), and results were compared with transfections using unmodified poly(lysine).DNA, unmodified SP-B.DNA, or DNA only. For [Lys]10kDa-SP-B.pCPA-RSV preparations, CAT activity was readily detectable above the background of [Lys]3.3kDa-SP-B or unmodified SP-B. The SP-B-poly(lysine) conjugates were effective over a broad range of protein-to-DNA molar ratios, although they were optimal at approximately 500:1-1000:1. Transfection efficiency varied with the tested cell line but was not specific to airway cells. Addition of replication-defective adenovirus to the [Lys]10kDa-SP-B.pCPA-RSV complex enhanced CAT activity about 30-fold with respect to that produced by the [Lys]10kDa-SP-B.pCPA-RSV complex alone. This increase suggests routing of the adenoviral.[Lys]10kDa-SP-B.pCPA-RSV complex through an endosomal pathway. Effects of covalent modification on the secondary structure of SP-B were examined by Fourier transform infrared spectrometry (FTIR). Results of FTIR indicated that the conformation of [Lys]10kDa-SP-B was

  7. Utilization of a photoactivatable antigen system to examine B-cell probing termination and the B-cell receptor sorting mechanisms during B-cell activation

    PubMed Central

    Wang, Jing; Tang, Shan; Wan, Zhengpeng; Gao, Yiren; Cao, Yiyun; Yi, Junyang; Si, Yanyan; Zhang, Haowen; Liu, Lei; Liu, Wanli

    2016-01-01

    Antigen binding to the B-cell receptor (BCR) induces several responses, resulting in B-cell activation, proliferation, and differentiation. However, it has been difficult to study these responses due to their dynamic, fast, and transient nature. Here, we attempted to solve this problem by developing a controllable trigger point for BCR and antigen recognition through the construction of a photoactivatable antigen, caged 4-hydroxy-3-nitrophenyl acetyl (caged-NP). This photoactivatable antigen system in combination with live cell and single molecule imaging techniques enabled us to illuminate the previously unidentified B-cell probing termination behaviors and the precise BCR sorting mechanisms during B-cell activation. B cells in contact with caged-NP exhibited probing behaviors as defined by the unceasing extension of membrane pseudopods in random directions. Further analyses showed that such probing behaviors are cell intrinsic with strict dependence on F-actin remodeling but not on tonic BCR signaling. B-cell probing behaviors were terminated within 4 s after photoactivation, suggesting that this response was sensitive and specific to BCR engagement. The termination of B-cell probing was concomitant with the accumulation response of the BCRs into the BCR microclusters. We also determined the Brownian diffusion coefficient of BCRs from the same B cells before and after BCR engagement. The analysis of temporally segregated single molecule images of both BCR and major histocompatibility complex class I (MHC-I) demonstrated that antigen binding induced trapping of BCRs into the BCR microclusters is a fundamental mechanism for B cells to acquire antigens. PMID:26764382

  8. Biological Effects of Particles with Very High Energy Deposition on Mammalian Cells Utilizing the Brookhaven Tandem Van de Graaff Accelerator

    NASA Technical Reports Server (NTRS)

    Saha, Janapriya; Cucinotta, Francis A.; Wang, Minli

    2013-01-01

    High LET radiation from GCR (Galactic Cosmic Rays) consisting mainly of high charge and energy (HZE) nuclei and secondary protons and neutrons, and secondaries from protons in SPE (Solar Particle Event) pose a major health risk to astronauts due to induction of DNA damage and oxidative stress. Experiments with high energy particles mimicking the space environment for estimation of radiation risk are being performed at NASA Space Radiation Laboratory at BNL. Experiments with low energy particles comparing to high energy particles of similar LET are of interest for investigation of the role of track structure on biological effects. For this purpose, we report results utilizing the Tandem Van de Graaff accelerator at BNL. The primary objective of our studies is to elucidate the influence of high vs low energy deposition on track structure, delta ray contribution and resulting biological responses. These low energy ions are of special relevance as these energies may occur following absorption through the spacecraft and shielding materials in human tissues and nuclear fragments produced in tissues by high energy protons and neutrons. This study will help to verify the efficiency of these low energy particles and better understand how various cell types respond to them.

  9. Adenosine triphosphate utilization rates and metabolic pool sizes in intact cells measured by transfer of 18O from water.

    PubMed Central

    Dawis, S M; Walseth, T F; Deeg, M A; Heyman, R A; Graeff, R M; Goldberg, N D

    1989-01-01

    The hydrolytic rates and metabolic pool sizes of ATP were determined in intact cells by monitoring the time courses of 18O incorporation from 18O-water into the gamma-phosphoryl of ATP and orthophosphate. To calculate the rate of ATP hydrolysis, a kinetic model is used to fit the time course of the 18O labeling. The size of the metabolic pool of ATP is calculated from the 18O distribution after isotopic equilibrium has been achieved. Metabolic pools have a binomial distribution of 18O whereas nonmetabolic pools exhibit negligible 18O labeling. The application and limitations of this approach are illustrated with data from isolated toad retinas and human platelets. At 22 degrees C, the time constant of ATP hydrolysis in the dark-adapted toad retina is about 30 s. Under these conditions, over 80% of the retinal ATP is involved in high-energy phosphate metabolism. It is calculated that when cGMP metabolic flux in the photoreceptors is maximally stimulated by light, it accounts for 10% of the ATP utilization by the entire retina. The time constant of ATP hydrolysis in human platelets at 37 degrees C is approximately 1 s, and 60% of the platelet ATP is involved in energy metabolism. PMID:2930826

  10. 40 CFR Appendix A to Part 76 - Phase I Affected Coal-Fired Utility Units With Group 1 or Cell Burner Boilers

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Phase I Affected Coal-Fired Utility Units With Group 1 or Cell Burner Boilers A Appendix A to Part 76 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES...