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Iess L, Militzer B, Kaspi Y, Nicholson P, Durante D, Racioppa P, Anabtawi A, Galanti E, Hubbard W, Mariani MJ, Tortora P, Wahl S, Zannoni M. Measurement and implications of Saturn’s gravity field and ring mass. Science 2019; 364:science.aat2965. [DOI: 10.1126/science.aat2965] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 12/19/2018] [Indexed: 11/03/2022]
Abstract
The interior structure of Saturn, the depth of its winds, and the mass and age of its rings constrain its formation and evolution. In the final phase of the Cassini mission, the spacecraft dived between the planet and its innermost ring, at altitudes of 2600 to 3900 kilometers above the cloud tops. During six of these crossings, a radio link with Earth was monitored to determine the gravitational field of the planet and the mass of its rings. We find that Saturn’s gravity deviates from theoretical expectations and requires differential rotation of the atmosphere extending to a depth of at least 9000 kilometers. The total mass of the rings is (1.54 ± 0.49) × 1019 kilograms (0.41 ± 0.13 times that of the moon Mimas), indicating that the rings may have formed 107 to 108 years ago.
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Affiliation(s)
- L. Iess
- Department of Mechanical and Aerospace Engineering, Sapienza Università di Roma, Rome 00184, Italy
| | - B. Militzer
- Department of Astronomy, University of California, Berkeley, Berkeley, CA 94720, USA
- Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Y. Kaspi
- Department of Earth and Planetary Sciences Weizmann Institute of Science, Rehovot 76100, Israel
| | - P. Nicholson
- Department of Astronomy, Cornell University, Ithaca, NY 14853, USA
| | - D. Durante
- Department of Mechanical and Aerospace Engineering, Sapienza Università di Roma, Rome 00184, Italy
| | - P. Racioppa
- Department of Mechanical and Aerospace Engineering, Sapienza Università di Roma, Rome 00184, Italy
| | - A. Anabtawi
- Jet Propulsion Laboratory–Caltech, Pasadena, CA 91109, USA
| | - E. Galanti
- Department of Earth and Planetary Sciences Weizmann Institute of Science, Rehovot 76100, Israel
| | - W. Hubbard
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
| | - M. J. Mariani
- Department of Mechanical and Aerospace Engineering, Sapienza Università di Roma, Rome 00184, Italy
| | - P. Tortora
- Department of Industrial Engineering, Università di Bologna, Forlì 47100, Italy
| | - S. Wahl
- Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, CA 94720, USA
| | - M. Zannoni
- Department of Industrial Engineering, Università di Bologna, Forlì 47100, Italy
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Petrusca D, Van Demark M, Hubbard W, Twigg H, Petrache I. Efferocytosis ő autophagy crosstalk in alveolar macrophages exposed to cigarette smoking (151.7). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.151.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Walter Hubbard
- Medicine Johns Hopkins UniversityBaltimoreMDUnited States
| | - Homer Twigg
- Medicine Indiana UniversityIndianapolisINUnited States
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Kelly KM, Beck SE, Metcalf Pate KA, Queen SE, Dorsey JL, Adams RJ, Avery LB, Hubbard W, Tarwater PM, Mankowski JL. Neuroprotective maraviroc monotherapy in simian immunodeficiency virus-infected macaques: reduced replicating and latent SIV in the brain. AIDS 2013; 27:F21-8. [PMID: 24051706 PMCID: PMC4235167 DOI: 10.1097/qad.0000000000000074] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 09/12/2013] [Accepted: 09/12/2013] [Indexed: 12/05/2022]
Abstract
OBJECTIVE HIV-associated neurocognitive deficits remain a challenge despite suppressive combined antiretroviral therapy. Given the association between HIV-induced central nervous system (CNS) disease and replication of HIV in immune-activated macrophages, CCR5 antagonists may attenuate CNS disease by modulating inflammatory signaling and by limiting viral replication. DESIGN To establish whether initiating CCR5 inhibition during early infection altered CNS disease progression, outcomes were compared between simian immunodeficiency virus (SIV)-infected macaques treated with maraviroc (MVC) versus untreated SIV-infected macaques. METHODS Six SIV-infected rhesus macaques were treated with MVC monotherapy for 5 months beginning 24 days postinoculation; 22 SIV-infected animals served as untreated controls. SIV RNA levels in plasma, cerobrospinal fluid, and brain, and CNS expression of TNFα and CCL2 were measured by qRT-PCR. Immunostaining for CD68 and amyloid precursor protein in the brain was measured by image analysis. Plasma sCD163 was measured by ELISA. RESULTS SIV RNA and proviral DNA levels in brain were markedly lower with MVC treatment, demonstrating CCR5 inhibition reduces CNS replication of SIV and may reduce the CNS latent viral reservoir. MVC treatment also lowered monocyte and macrophage activation, represented by CNS CD68 immunostaining and plasma sCD163 levels, and reduced both TNFα and CCL2 RNA expression in brain. Treatment also reduced axonal amyloid precursor protein immunostaining to levels present in uninfected animals, consistent with neuroprotection. CONCLUSION CCR5 inhibitors may prevent neurologic disorders in HIV-infected individuals by reducing inflammation and by limiting viral replication in the brain. Furthermore, CCR5 inhibitors may reduce the latent viral reservoir in the CNS. Adding CCR5 inhibitors to combined antiretroviral regimens may offer multiple neuroprotective benefits.
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Affiliation(s)
- Kathleen M Kelly
- aDepartment of Molecular and Comparative Pathobiology bDepartment of Pharmacology and Molecular Sciences cDivision of Clinical Pharmacology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland dDepartment of Biostatistics, Texas Tech University School of Medicine, El Paso Texas eDepartment of Neurology fDepartment of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Kamocki K, Van Demark M, Fisher A, Rush NI, Presson RG, Hubbard W, Berdyshev EV, Adamsky S, Feinstein E, Gandjeva A, Tuder RM, Petrache I. RTP801 is required for ceramide-induced cell-specific death in the murine lung. Am J Respir Cell Mol Biol 2012; 48:87-93. [PMID: 23024063 DOI: 10.1165/rcmb.2012-0254oc] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Key host responses to the stress induced by environmental exposure to cigarette smoke (CS) are responsible for initiating pathogenic effects that may culminate in emphysema development. CS increases lung ceramides, sphingolipids involved in oxidative stress, structural alveolar cell apoptosis, and inhibition of apoptotic cell clearance by alveolar macrophages, leading to the development of emphysema-like pathology. RTP801, a hypoxia and oxidative stress sensor, is also increased by CS, and has been recently implicated in both apoptosis and inflammation. We investigated whether inductions of ceramide and RTP801 are mechanistically linked, and evaluated their relative importance in lung cell apoptosis and airspace enlargement in vivo. As reported, direct lung instillation of either RTP801 expression plasmid or ceramides in mice triggered alveolar cell apoptosis and oxidative stress. RTP801 overexpression up-regulated lung ceramide levels 2.6-fold. In turn, instillation of lung ceramides doubled the lung content of RTP801. Cell sorting after lung tissue dissociation into single-cell suspension showed that ceramide triggers both endothelial and epithelial cell apoptosis in vivo. Interestingly, mice lacking rtp801 were protected against ceramide-induced apoptosis of epithelial type II cells, but not type I or endothelial cells. Furthermore, rtp801-null mice were protected from ceramide-induced alveolar enlargement, and exhibited improved static lung compliance compared with wild-type mice. In conclusion, ceramide and RTP801 participate in alveolar cell apoptosis through a process of mutual up-regulation, which may result in self-amplification loops, leading to alveolar damage.
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Affiliation(s)
- Krzysztof Kamocki
- Department of Biochemistry and Molecular Biology, Indianapolis, IN 46202, USA
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Yokoi H, Choi OH, Hubbard W, Lee HS, Canning BJ, Lee HH, Ryu SD, von Gunten S, Bickel CA, Hudson SA, Macglashan DW, Bochner BS. Inhibition of FcepsilonRI-dependent mediator release and calcium flux from human mast cells by sialic acid-binding immunoglobulin-like lectin 8 engagement. J Allergy Clin Immunol 2007; 121:499-505.e1. [PMID: 18036650 DOI: 10.1016/j.jaci.2007.10.004] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 09/30/2007] [Accepted: 10/02/2007] [Indexed: 01/18/2023]
Abstract
BACKGROUND Sialic acid-binding immunoglobulin-like lectins (Siglecs) are a family of glycan-binding inhibitory receptors, and among them, Siglec-8 is selectively expressed on human eosinophils, basophils, and mast cells. On eosinophils, Siglec-8 engagement induces apoptosis, but its function on mast cells is unknown. OBJECTIVE We sought to study the effect of Siglec-8 engagement on human mast cell survival and mediator release responses. METHODS Human mast cells were generated from CD34+ precursors. Apoptosis was studied by using flow cytometry. Mast cell mediator release or human lung airway smooth muscle contraction was initiated by FcepsilonRI cross-linking with or without preincubation with Siglec-8 or control antibodies, and release of mediators was analyzed along with Ca++ flux. RBL-2H3 cells transfected with normal and mutated forms of Siglec-8 were used to study how Siglec-8 engagement alters mediator release. RESULTS Siglec-8 engagement failed to induce human mast cell apoptosis. However, preincubation with Siglec-8 mAbs significantly (P < .05) inhibited FcepsilonRI-dependent histamine and prostaglandin D(2) release, Ca++ flux, and anti-IgE-evoked contractions of human bronchial rings. In contrast, release of IL-8 was not inhibited. Siglec-8 ligation was also shown to inhibit beta-hexosaminidase release and Ca++ flux triggered through FcepsilonRI in RBL-2H3 cells transfected with full-length human Siglec-8 but not in cells transfected with Siglec-8 containing a tyrosine to phenylalanine point mutation in the membrane-proximal immunoreceptor tyrosine-based inhibitory motif domain. CONCLUSION These data represent the first reported inhibitory effects of Siglec engagement on human mast cells.
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MESH Headings
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Antigens, Differentiation, B-Lymphocyte/genetics
- Antigens, Differentiation, B-Lymphocyte/metabolism
- Bronchi/physiology
- Calcium/metabolism
- Cell Survival/physiology
- Cells, Cultured
- Histamine Release
- Humans
- Interleukin-8/metabolism
- Lectins/genetics
- Lectins/metabolism
- Mast Cells/metabolism
- Mast Cells/physiology
- Muscle Contraction/physiology
- Muscle, Smooth/physiology
- Prostaglandin D2/metabolism
- Receptors, IgE/antagonists & inhibitors
- Receptors, IgE/metabolism
- Transfection
- beta-N-Acetylhexosaminidases/metabolism
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Affiliation(s)
- Hidenori Yokoi
- Department of Medicine, Division of Allergy and Clinical Immunology, Johns Hopkins University School of Medicine, and the Johns Hopkins Asthma and Allergy Center, Baltimore, MD 21224, USA
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6
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Georas SN, Berdyshev E, Hubbard W, Gorshkova IA, Usatyuk PV, Saatian B, Myers AC, Williams MA, Xiao HQ, Liu M, Natarajan V. Lysophosphatidic acid is detectable in human bronchoalveolar lavage fluids at baseline and increased after segmental allergen challenge. Clin Exp Allergy 2007; 37:311-22. [PMID: 17359381 DOI: 10.1111/j.1365-2222.2006.02626.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Lysophosphatidic acid (LPA) is a biologically active lysophospholipid and a component of normal plasma. LPA binds to receptors expressed on circulating and structural lung cells and affects cell growth and activation. Whether LPA is present in the lung has not been previously reported. OBJECTIVE To develop an assay to measure LPA in bronchoalveolar lavage (BAL) fluids, and to study the association between LPA and allergic airway inflammation. METHODS Seventeen allergic subjects underwent bronchoscopy and segmental allergen challenge, followed 18 h later by BAL. Supernatants were analysed for LPA content using liquid chromatography and mass spectroscopy. Expression of LPA receptors on primary bronchial epithelial cells was analysed by immunolabelling, and the effects of LPA on epithelial cell barrier function was investigated by measuring transepithelial resistance. RESULTS LPA was detectable in BAL from control lung segments, and significantly increased 18 h after allergen challenge. Polyunsaturated species of LPA were especially increased following segmental allergen challenge. LPA levels did not strongly correlate with the number or percentages of eosinophils, neutrophils of lymphocytes, whereas MIP-3alpha (CCL20) levels correlated significantly with the allergen-driven influx of lymphocytes. The levels of LPA from control sites correlated inversely with BAL protein content, suggesting that LPA promoted epithelial barrier integrity at baseline. Experiments using primary human bronchial epithelial cells confirmed that LPA tightened the epithelial cell barrier. CONCLUSION Lysophosphatidic acid is detectable in human BAL fluids at baseline and its expression increases during allergic inflammation. LPA does not appear to be a dominant chemoattractant for eosinophils or lymphocytes during allergic airway inflammation. In the absence of ongoing inflammation, LPA may promote epithelial barrier integrity.
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Affiliation(s)
- S N Georas
- Division of Pulmonary & Critical Care Medicine, The Johns Hopkins Asthma & Allergy Center, Baltimore, MD, USA.
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7
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Berdyshev EV, Gorshkova IA, Usatyuk P, Zhao Y, Saatian B, Hubbard W, Natarajan V. De novo biosynthesis of dihydrosphingosine-1-phosphate by sphingosine kinase 1 in mammalian cells. Cell Signal 2006; 18:1779-92. [PMID: 16529909 DOI: 10.1016/j.cellsig.2006.01.018] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2005] [Revised: 01/25/2006] [Accepted: 01/26/2006] [Indexed: 10/24/2022]
Abstract
Sphingosine kinase 1 (SK1) is one of the two known kinases, which generates sphingosine-1-phosphate (S1P), a potent endogenous lipid mediator involved in cell survival, proliferation, and cell-cell interactions. Activation of SK1 and intracellular generation of S1P were suggested to be part of the growth and survival factor-induced signaling, and overexpression of SK1 provoked cell tumorigenic transformation. Using a highly selective and sensitive LC-MS/MS approach, here we show that SK1 overexpression, but not SK2, in different primary cells and cultured cell lines results in predominant upregulation of the synthesis of dihydrosphingosine-1-phosphate (DHS1P) compared to S1P. Stable isotope pulse-labeling experiments in conjunction with LC-MS/MS quantitation of different sphingolipids demonstrated strong interference of overexpressed SK1 with the de novo sphingolipid biosynthesis by deviating metabolic flow of newly formed sphingoid bases from ceramide formation toward the synthesis of DHS1P. On the contrary, S1P biosynthesis was not directly linked to the de novo sphingoid bases transformations and was dependent on catabolic generation of sphingosine from complex sphingolipids. As a result of SK1 overexpression, migration and Ca2+-response of human pulmonary artery endothelial cells (HPAEC) to stimulation with external S1P, but not thrombin, was strongly impaired. In contrast, selective increase in intracellular content of DHS1P or S1P through the uptake and phosphorylation of corresponding sphingoid bases had no effect on S1P-induced signaling or facilitation of wound healing. Furthermore, infection of human bronchial epithelial cells (HBEpC) with RSV A-2 virus increased SK1-mediated synthesis of DHS1P and S1P, whereas TNF-alpha enhanced only S1P production in HPAEC. These findings uncover a new functional role for SK1, which can control survival/death (DHS1P-S1P/ceramides) balance by targeting sphingolipid de novo biosynthesis and selectively generating DHS1P at a metabolic step preceding ceramide formation.
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Affiliation(s)
- Evgeny V Berdyshev
- The University of Chicago, Biological Sciences Division, Department of Medicine, 929 E. 57th Street, Room W403M, Chicago, IL 60637, USA.
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Berdyshev E, Gorshkova I, Usatyuk P, Zhao Y, Saatian B, Hubbard W, Natarajan V. 9 A NOVEL ROLE OF SPHINGOSINE KINASE 1 IN THE DE NOVO BIOSYNTHESIS OF DIHYDROSPHINGOSINE-1-PHOSPHATE IN MAMMALIAN CELLS. J Investig Med 2006. [DOI: 10.2310/6650.2005.x0015.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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9
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Berdyshev E, Gorshkova I, Usatyuk P, Zhao Y, Saatian B, Hubbard W, Natarajan V. A Novel Role of Sphingosine Kinase 1 in the de novo Biosynthesis of Dihydrosphingosine‐1‐Phosphate in Mammalian Cells. FASEB J 2006. [DOI: 10.1096/fasebj.20.4.a89] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- E. Berdyshev
- University of Chicago929 E. 57th StreetChicagoIL60637
| | - I. Gorshkova
- University of Chicago929 E. 57th StreetChicagoIL60637
| | - P. Usatyuk
- University of Chicago929 E. 57th StreetChicagoIL60637
| | - Y. Zhao
- University of Chicago929 E. 57th StreetChicagoIL60637
| | - B. Saatian
- The Johns Hopkins University5501 Bayview CircleBaltimoreMD21224
| | - W. Hubbard
- The Johns Hopkins University5501 Bayview CircleBaltimoreMD21224
| | - V. Natarajan
- University of Chicago929 E. 57th StreetChicagoIL60637
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Berdyshev E, Gorshkova I, Usatyuk P, Zhao Y, Saatian B, Hubbard W, Natarajan V. A Novel Role of Sphingosine Kinase 1 in the De Novo Biosynthesis of Dihydrosphingosine-1-Phosphate in Mammalian Cells. J Investig Med 2006. [DOI: 10.1177/108155890605402s09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- E. Berdyshev
- Department of Medicine, The University of Chicago, Chicago, IL
| | - I. Gorshkova
- Department of Medicine, The University of Chicago, Chicago, IL
| | - P. Usatyuk
- Department of Medicine, The University of Chicago, Chicago, IL
| | - Y. Zhao
- Department of Medicine, The University of Chicago, Chicago, IL
| | - B. Saatian
- The Johns Hopkins University Baltimore, MD
| | - W. Hubbard
- The Johns Hopkins University Baltimore, MD
| | - V. Natarajan
- Department of Medicine, The University of Chicago, Chicago, IL
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Giardiello FM, Casero RA, Hamilton SR, Hylind LM, Trimbath JD, Geiman DE, Judge KR, Hubbard W, Offerhaus GJA, Yang VW. Prostanoids, ornithine decarboxylase, and polyamines in primary chemoprevention of familial adenomatous polyposis. Gastroenterology 2004; 126:425-31. [PMID: 14762779 PMCID: PMC2225536 DOI: 10.1053/j.gastro.2003.11.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS Familial adenomatous polyposis because of germline mutation of the adenomatous polyposis coli gene is characterized by development of colorectal adenomas and, ultimately, colorectal cancer. The usefulness of colorectal mucosal compounds to predict the effect on adenoma development of primary chemoprevention with the nonsteroidal anti-inflammatory drug sulindac was evaluated. METHODS A randomized, double-blind, placebo-controlled study of 41 subjects genotypically affected with familial adenomatous polyposis but phenotypically unaffected was conducted. Patients received either sulindac or placebo for 48 months, and development of new adenomas was evaluated. The levels of 5 prostanoids, ornithine decarboxylase, and polyamines were measured serially in normal-appearing rectal mucosa. RESULTS There were no statistically significant differences between treatment groups in baseline levels of prostanoids, ornithine decarboxylase, or polyamines. At conclusion of the study, 4 of 5 prostaglandin levels were statistically significantly lower in the sulindac group than in the placebo group. Among the subset of patients taking sulindac, 3 of 5 prostaglandin levels were statistically significantly lower in patients who were polyp free than in those who developed polyps. By contrast, there were no statistically significant differences in ornithine decarboxylase or polyamines between treatment groups or in those on sulindac who were polyp free compared with those who developed polyps. CONCLUSIONS Colorectal mucosal prostaglandin levels, but not ornithine decarboxylase or polyamines, may be valuable biomarkers to assess appropriate drug dosage and medication compliance in patients undergoing primary chemoprevention therapy with sulindac. Reduction of mucosal prostaglandin levels may be necessary to achieve chemopreventive benefit from this agent.
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Affiliation(s)
- Francis M Giardiello
- Department of Medicine, and Oncology Center, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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12
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Scott D, Finke H, Hubbard W, McCullough J, Gross M, Williamson K, Waddington G, Huffman H. Spiropentane: Heat Capacity, Heats of Fusion and Vaporization, Vapor Pressure, Entropy and Thermodynamic Functions - Correction. J Am Chem Soc 2002. [DOI: 10.1021/ja01144a605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Giardiello FM, Yang VW, Hylind LM, Krush AJ, Petersen GM, Trimbath JD, Piantadosi S, Garrett E, Geiman DE, Hubbard W, Offerhaus GJA, Hamilton SR. Primary chemoprevention of familial adenomatous polyposis with sulindac. N Engl J Med 2002; 346:1054-9. [PMID: 11932472 PMCID: PMC2225537 DOI: 10.1056/nejmoa012015] [Citation(s) in RCA: 233] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Familial adenomatous polyposis is caused by a germ-line mutation in the adenomatous polyposis coli gene and is characterized by the development of hundreds of colorectal adenomas and, eventually, colorectal cancer. Nonsteroidal antiinflammatory drugs can cause regression of adenomas, but whether they can prevent adenomas is unknown. METHODS We conducted a randomized, double-blind, placebo-controlled study of 41 young subjects (age range, 8 to 25 years) who were genotypically affected with familial adenomatous polyposis but phenotypically unaffected. The subjects received either 75 or 150 mg of sulindac orally twice a day or identical-appearing placebo tablets for 48 months. The number and size of new adenomas and side effects of therapy were evaluated every four months for four years, and the levels of five major prostaglandins were serially measured in biopsy specimens of normal-appearing colorectal mucosa. RESULTS After four years of treatment, the average rate of compliance exceeded 76 percent in the sulindac group, and mucosal prostaglandin levels were lower in this group than in the placebo group. During the course of the study, adenomas developed in 9 of 21 subjects (43 percent) in the sulindac group and 11 of 20 subjects in the placebo group (55 percent) (P=0.54). There were no significant differences in the mean number (P=0.69) or size (P=0.17) of polyps between the groups. Sulindac did not slow the development of adenomas, according to an evaluation involving linear longitudinal methods. CONCLUSIONS Standard doses of sulindac did not prevent the development of adenomas in subjects with familial adenomatous polyposis.
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Affiliation(s)
- Francis M Giardiello
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, USA
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Abstract
Recent advances in the design of immunotoxins (IT) have yielded significant improvements. FN18-CRM9, a construct of anti-CD3 epsilon mAb FN18 and mutated diphtheria toxin CRM9 has exhibited high specificity, low systemic toxicity and unusual efficacy compared to previous iterations of immunotoxins. Others and we have examined this anti-CD3-IT for the purpose of inducing immunological tolerance through selective ablation of T cells in rhesus macaques and have obtained encouraging results. In order to characterize its mode of action, we have examined its effects on peripheral blood and lymph node T cell killing in vitro. We have studied the cytotoxic mechanism induced by this anti-CD3-IT as well as its effects on proliferation, phenotypic changes and cytokine production (IL2, IFN gamma and TNF alpha). The results indicate that anti-CD3-IT was highly specific for T cell killing at doses as low as 1 x 10(6) micrograms/ml and showed a maximal effect at 48 h after exposure. The toxicity was restricted to T cells, as B cells and other bystander cells were spared. This immunotoxin was shown to induce T cell apoptosis, as assessed by TUNEL assay, DNA content and cytotoxicity. Fas expression was upregulated on T cells within 24 h after in vitro exposure to anti-CD3-IT, suggesting an early T cell activation phase prior to T cell death. T cell killing was manifest as an early cell cycle arrest at the G1/S phase transition, which appeared to virtually eliminate the production of cytokines. These findings corroborate the temporal, specificity and quantitative patterns for anti-CD3 immunotoxin administration previously observed in vivo.
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Affiliation(s)
- G Meng
- University of Alabama at Birmingham, USA
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15
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Abstract
Calcium pyrophosphate dihydrate (CPPD) and basic calcium phosphate (BCP) crystals [hydroxyapatite (HA), octacalcium phosphate, tricalcium phosphate] are common in osteoarthritis knee effusions, and are often associated with low-grade synovial proliferation and inflammation. Calcium-containing crystals including HA, are known to have a number of biologic effects on culture cells such induction of mitogenesis, stimulation of Prostaglandin E2 (PGE2) production via the phospholipase A2/cyclo-oxygenase pathway, activation of phospholipase C and inositol phospholipid hydrolysis, induction of metalloproteinase synthesis and induction of proto-oncogenes (c-fos and c-myc). While endocytosis of HA particles is prerequisite of the mitogenic effect of calcium-containing crystals in fibroblasts, it is not known whether endocytosis is required for crystal-induced metalloproteinase synthesis. In the present series of experiments, we examine the effect of three different sizes (106, 46, and 17 microns mean diameters) well-characterized spherical HA particles on the induction of mitogenesis and metalloproteinase synthesis on human fibroblasts. We showed that endocytosis is required for HA particles to induce synthesis of metalloproteinases.
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Affiliation(s)
- H S Cheung
- Division of Rheumatology, Medical College of Wisconsin, Milwaukee 53226, USA
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Affiliation(s)
- R M Naclerio
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, USA
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17
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Patel DJ, Holdright DR, Knight CJ, Mulcahy D, Thakrar B, Wright C, Sparrow J, Wicks M, Hubbard W, Thomas R, Sutton GC, Hendry G, Purcell H, Fox K. Early continuous ST segment monitoring in unstable angina: prognostic value additional to the clinical characteristics and the admission electrocardiogram. Heart 1996; 75:222-8. [PMID: 8800982 PMCID: PMC484276 DOI: 10.1136/hrt.75.3.222] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND AND OBJECTIVE In unstable angina, clinical characteristics, resting electrocardiography, and early continuous ST segment monitoring have been individually reported to identify subgroups at increased risk of adverse outcome. It is not known, however, whether continuous ST monitoring provides additional prognostic information in such a setting. DESIGN Observational study of 212 patients with unstable angina without evidence of acute myocardial infarction admitted to district general hospitals, who had participated in a randomised study comparing heparin and aspirin treatment versus aspirin alone. METHODS Clinical variables and a 12 lead electrocardiogram (ECG) were recorded at admission, and treatment was standardised to include aspirin, atenolol, diltiazem, and intravenous glyceryl trinitrate, in addition to intravenous heparin (randomised treatment). Continuous ST segment monitoring was performed for 48 h and all inhospital adverse events were recorded. RESULTS The admission ECG was normal in 61 patients (29%), showed ST depression in 59 (28%) (17 > or = 0.1 mV), and T wave changes in a further 69 (33%). The remaining 23 had Q waves (18), right bundle branch block (four), or ST elevation (one). During 8963 h of continuous ST segment monitoring (mean 42.3 h/patient), 132 episodes of transient myocardial ischaemia (104 silent) were recorded in 32 patients (15%). Forty patients (19%) had an adverse event (cardiac deaths (n = 3), non-fatal myocardial infarction (n = 6) and, emergency revascularisation (n = 31)). Both admission ECG ST depression (P = 0.02), and transient ischaemia (P < 0.001) predicted an increased risk of non-fatal myocardial infarction or death, while no patients with a normal ECG died or had a myocardial infarction. Adverse outcome was predicted by admission ECG ST depression (regardless of severity) (odds ratio (OR) 3.41) (P < 0.001), and maintenance beta blocker treatment (OR 2.95) (P < 0.01). A normal ECG predicted a favourable outcome (OR 0.38) (P = 0.04), while T wave or other ECG changes were not predictive of outcome. Transient ischaemia was the strongest predictor of adverse prognosis (OR 4.61) (P < 0.001), retaining independent predictive value in multivariate analysis (OR 2.94) (P = 0.03), as did maintenance beta blocker treatment (OR 2.85) (P = 0.01) and admission ECG ST depression, which showed a trend towards independent predictive value (OR 2.11) (P = 0.076). CONCLUSIONS Patients with unstable angina and a normal admission ECG have a good prognosis, while ST segment depression predicts an adverse outcome. Transient myocardial ischaemia detected by continuous ST segment monitoring in such patients receiving optimal medical treatment provides prognostic information additional to that gleaned from the clinical characteristics or the admission ECG.
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Hubbard W. Intervention in coronary artery disease. Practitioner 1995; 239:710-2. [PMID: 8871478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Weinmann GG, Liu MC, Proud D, Weidenbach-Gerbase M, Hubbard W, Frank R. Ozone exposure in humans: inflammatory, small and peripheral airway responses. Am J Respir Crit Care Med 1995; 152:1175-82. [PMID: 7551367 DOI: 10.1164/ajrccm.152.4.7551367] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We exposed eight normal adults to filtered air (FA) and 0.35 ppm ozone (O3) and compared responses in spirometry, including isovolume (isoV) flows at intermediate-to-low lung volumes, against levels of inflammatory markers in bronchoalveolar lavage fluid (BALF) and peripheral lung resistance (Rp) measured through a wedged bronchoscope. Spirometry was performed at the end, 25 min and 24 h after exposure, bronchoscopy at 24 h after exposure. The percentages of neutrophils, fibrinogen, albumin, PGE2, PGF2 alpha, and kinins were elevated in BALF after O3 compared with FA. The percentage reduction in (isoV) FEF25-75 at 25 min and 24 h after administration of O3 correlated closely with the rise in fibrinogen concentrations in BALF, a marker of altered vascular permeability. Rp, a measurement dominated by very small or peripheral airways, was unaffected in 7 of 8 subjects. The absence of change in Rp might have reflected insufficient penetration of O3 into these airways to produce or sustain an effect for 24 h; alternatively, the bronchoscopic procedure which included atropine and lidocaine pretreatment may have reversed an O3 effect. An unexpected finding was the significant association between baseline Rp (after FA) and the magnitude of the spirometric response to O3. Our results suggest that small airway dysfunction in the immediate post-O3 period is a marker of lung inflammation.
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Affiliation(s)
- G G Weinmann
- Department of Environmental Health Sciences, Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland, USA
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Holdright D, Patel D, Cunningham D, Thomas R, Hubbard W, Hendry G, Sutton G, Fox K. Comparison of the effect of heparin and aspirin versus aspirin alone on transient myocardial ischemia and in-hospital prognosis in patients with unstable angina. J Am Coll Cardiol 1994; 24:39-45. [PMID: 8006281 DOI: 10.1016/0735-1097(94)90539-8] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVES This study compared the effects of heparin and aspirin versus aspirin alone on transient myocardial ischemia and in-hospital prognosis in patients with unstable angina. BACKGROUND Transient myocardial ischemia occurring in patients with unstable angina is associated with an adverse prognosis. Heparin and aspirin are two drugs used frequently in the treatment of this condition, but the effect of combination therapy versus aspirin alone on transient myocardial ischemia is unknown. METHODS Two hundred eighty-five consecutive patients with unstable angina were randomized to receive either intravenous heparin plus oral aspirin (150 mg once daily) (Group H + A) or aspirin alone (Group A). Patients also received a beta-adrenergic blocking agent, diltiazem and intravenous nitrates. ST segment monitoring was performed for the 1st 48 h of treatment. Patients were followed up for the duration of their in-hospital stay. RESULTS One hundred fifty-four patients (30 women, mean [+/- SEM] age 58.3 +/- 0.8 years) received heparin and aspirin (Group H + A), and 131 patients (26 women, mean age 60.6 +/- 0.8 years) received aspirin only (Group A). ST segment monitoring (11,622 h) yielded 244 episodes of transient myocardial ischemia of a total duration of 7,819 min. There were no significant differences between the two treatment arms in the number of patients with transient myocardial ischemia (27 [18%] in Group H + A vs. 31 [24%] in Group A), number of episodes (96 in Group H + A vs. 148 in Group A) or total duration of transient myocardial ischemia (2,911 min in Group H + A vs. 4,908 min in Group A). The incidence of in-hospital myocardial infarction or death was significantly higher in patients with transient myocardial ischemia (53% vs. 22%, p < 0.0001). Five of the six deaths occurred in patients with transient myocardial ischemia. Event-free survival from myocardial infarction or death was similar in both treatment groups. Preadmission therapy with aspirin was associated with a lower in-hospital infarction rate (19% vs. 34%, p = 0.01). CONCLUSIONS The presence of transient myocardial ischemia in patients with unstable angina is associated with a significantly higher incidence of myocardial infarction or death in hospital. Combined therapy with heparin and aspirin compared with aspirin alone makes no difference in the development of these events, nor does it reduce the development of transient myocardial ischemia.
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Affiliation(s)
- D Holdright
- Royal Brompton National Heart and Lung Hospital, London, United Kingdom
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Abstract
The influence of specific antigen challenge on the excitability of C-cells in nodose ganglia isolated from actively sensitized guinea pigs was evaluated using intracellular recording techniques. Antigen (ovalbumin) caused a significant depolarization (approximately 8 mV) of the resting membrane potential. Antigen exposure had differing effects on the membrane input impedance; decreasing it in 15 neurons, increasing it in 6 neurons, and having no effect in 8 neurons. About 20% of guinea pig nodose C-cells reveal a long-lasting after-spike hyperpolarization (AHPslow). Antigen challenge reversibly blocked the AHPslow in 4 of 18 neurons studied in 18 ganglia. About 30% of the nodose ganglion neurons display a time- and voltage-dependent inward rectification at membrane potentials more negative than -75 mV. Exposing the ganglion to the sensitizing antigen consistently blocked this response in 8 of 8 neurons. Histological assessment of toluidine blue stained cells revealed that the nodose ganglion contained approximately 100 mast cells. Exposing the ganglion to ovalbumin stimulated mast cell degranulation, as measured by a decrease in number of stained cells, and evoked the release of histamine, PGD2, and immunoreactive peptidoleukotrienes from the tissue. The results support the hypothesis that endogenous inflammatory mediators released during the immediate hypersensitivity (allergic) reactions can modulate the excitability of primary C-fiber afferents. Mechanisms underlying antigen-induced neuromodulation of these neurons include depolarization of the resting membrane potential, changes in membrane resistance, blockade of a time- and voltage-dependent anomalous rectifier, and, in some cells, blockade of the AHPslow.
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Affiliation(s)
- B J Undem
- Johns Hopkins University School of Medicine, Department of Medicine, Baltimore, Maryland
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Hubbard W, Bauer D. Programme evaluation: What we can learn from the United States experience. Aust J Physiother 1993; 39:53-57. [PMID: 25026063 DOI: 10.1016/s0004-9514(14)60470-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The introduction of performance outcome measurement to Australian rehabilitation services is now on the agenda. The Functional Independence Measure (FIM) is being actively promoted as an appropriate system. This paper outlines the philosophy and evolution of the FIM in the United States of America (USA), and emphasises the positive aspects of accountability through global functional measurement. Physiotherapists are encouraged to be positive and innovative in their approach to the use of this accountability tool to ensure that physiotherapy continues to be seen as a primary discipline in the global functional context of the rehabilitation process.
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Abstract
To determine the effect of mediators released from cultured canine bronchial epithelial cells on contraction of canine tracheal smooth muscle, we treated smooth muscle strips with piperazine-N,N'-bis(2-ethanesulfonic acid) buffer "conditioned" by 5 h incubation with cultures of 4- to 5-day-old cultured epithelial cells. Pretreatment of tracheal smooth muscle with conditioned buffer for 5 min resulted in a significant shift to the right of the contractile dose-response curve to histamine in the range of 10(-8) to 5 x 10(-4) M. In addition, conditioned buffer induced a dose-related relaxation of the muscle precontracted by histamine (5 microM). Relaxant activity was also evident against tissues precontracted by 5-hydroxytryptamine or methacholine. Lipid extraction of conditioned buffer reduced its activity to that of the fresh buffer control. Prior treatment of the cells in culture with the cyclooxygenase inhibitor, sodium meclofenamate (4 microM), markedly reduced the relaxant effect of the conditioned buffer, whereas prior treatment with MK-886, an inhibitor of 5-lipoxygenase, did not alter relaxant activity. Analysis of prostanoids released into the buffer by epithelial cells indicated the presence of prostaglandin E2 (PGE2) and 6-ketoprostaglandin F1 alpha, the former in concentrations sufficient to account for the effect of conditioned buffer on precontracted tracheal muscle. Prostaglandin I2 appeared to have a synergistic effect on PGE2-induced relaxation. We conclude that canine bronchial epithelial cells exhibit baseline release of a relaxant lipid factor(s) that can both inhibit and reverse the contraction of tracheal smooth muscle by histamine.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- X Y Yu
- Department of Environmental Health Sciences, School of Hygiene and Public Health, Johns Hopkins Medical Institutions, Baltimore, Maryland 21205
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Abstract
The natural history of chronotropic incompetence is not clear. To assess this, we evaluated corrected sinus node recovery time (cSNRT) and sinus node chronotropy at rest and during exercise in two groups of syncopal patients with sinus node disease. Group A comprised patients with resting bradycardia but normal cSNRT and group B had resting bradycardia and prolonged cSNRT (greater than 1000 ms). An additional two groups (C and D) were studied. Group C comprised patients with complete AV (CAVB) and no evidence of sinus node disease and group D were asymptomatic controls of similar age. At diagnosis, patients with symptomatic bradycardia but normal cSNRT and no evidence of carotid sinus syndrome (group A) had resting bradycardia and impaired peak heart rate (PHR-I) on exercise compared to controls (P less than 0.001 and P less than 0.05, respectively), but no reduction in exercise duration. At follow-up group A patients demonstrated an increase in resting rate that was significantly slower than the controls (P less than 0.01). Peak heart rate (PHR-II) also remained significantly slower (P less than 0.05). There was no difference in exercise duration between groups A and D at follow-up. Group B was further subdivided according to follow-up findings of preservation of atrial activity in seven patients (group B-1) and junctional rhythm without any atrial activity in four patients (group B-2). Retrospective analysis showed no significant difference in resting heart rate at initial examination but group B-2 showed a significantly lower peak heart rate on exercise compared with B-1 (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P E Vardas
- Westminster Hospital, Cardiac Department, London, United Kingdom
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Abstract
The ability of learning networks to generalize can be greatly enhanced by providing constraints from the task domain. This paper demonstrates how such constraints can be integrated into a backpropagation network through the architecture of the network. This approach has been successfully applied to the recognition of handwritten zip code digits provided by the U.S. Postal Service. A single network learns the entire recognition operation, going from the normalized image of the character to the final classification.
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Affiliation(s)
- Y. LeCun
- AT&T Bell Laboratories, Holmdel, NJ 07733 USA
| | - B. Boser
- AT&T Bell Laboratories, Holmdel, NJ 07733 USA
| | | | | | | | - W. Hubbard
- AT&T Bell Laboratories, Holmdel, NJ 07733 USA
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Warner JA, Peters SP, Lichtenstein LM, Hubbard W, Yancey KB, Stevenson HC, Miller PJ, MacGlashan DW. Differential release of mediators from human basophils: differences in arachidonic acid metabolism following activation by unrelated stimuli. J Leukoc Biol 1989; 45:558-71. [PMID: 2470847 DOI: 10.1002/jlb.45.6.558] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We have examined the release of histamine and LTC4 from purified human basophils challenged with several different stimuli, both physiological and nonphysiological. Basophils (n = 16) challenged with 0.1 micrograms/ml anti-IgE released 38 +/- 4% of their available histamine and 39 +/- 12 ng LTC4/10(6) basophils within 15-30 min. F-Met peptide (n = 8) caused the release of 54 +/- 8% histamine and 42 +/- 25 ng LTC4/10(6) basophils within a period of 2-5 min. C5a caused the release of 22 +/- 3% histamine from selected donors but failed to initiate any LTC4 release unless combined with D2O or 5 mM extracellular calcium. The two nonphysiological stimuli A23187 and TPA caused extensive histamine release, 67 +/- 8 and 82 +/- 11%, respectively, and while A23187 initiated a large and rapid release of leukotriene, TPA failed to release any LTC4 even when combined with D2O or 2-5 mM extracellular calcium. Increased concentrations of extracellular calcium enhanced anti-IgE and f-Met peptide induced release of LTC4 but inhibited the A23187 induced release of leukotriene. A single peak of immunoreactive leukotriene C4 that comigrated with the authentic standard was identified using HPLC followed by radioimmunoassay. No LTD4 or LTE4 could be detected. Purified human basophils incubated with 0.2 microM [3H]AA incorporated 290 pmol/10(6) cells, or 32 +/- 5% of the available label within 60 min. The [3H]AA was taken principally into the phospholipids (73 +/- 5%), with 20 +/- 3% as neutral lipid, and only 5 +/- 2% remaining as the free acid. Three phospholipid subclasses, phosphatidylcholine, PC (24 +/- 2%), phosphatidylinositol, PI (22 +/- 1%), and phosphatidylethanolamine, PE (15 +/- 3%), accounted for the majority of the incorporated [3H]AA while the remainder of the phospholipids accounted for less than 5% of the total cpm. HPLC analysis of the lipid mediators released during stimulation with 0.1 micrograms/ml anti-IgE revealed [3H]LTC4 (2.4 +/- 1.0%), [3H]5HETE (1.0 +/- 0.1%), unmetabolized [3H]AA (91 +/- 2%), and an unidentified peak (3.4 +/- 1.4%). The unknown metabolite eluted with the prostaglandins, was inhibited by indomethacin, and appeared to have a relatively high specific activity. It may thus represent an artifact of the labeling procedure rather than a novel basophil-derived prostaglandin.
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Affiliation(s)
- J A Warner
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21239
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Jackel LD, Howard RE, Denker JS, Hubbard W, Solla SA. Building a hierarchy with neural networks: an example-image vector quantization. Appl Opt 1987; 26:5081-5084. [PMID: 20523487 DOI: 10.1364/ao.26.005081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Electronic neural networks can perform the function of associative memory. Given an input pattern, the network searches through its stored memories to find which of them best matches the input. Thus the network does a combination of content-addressable search and error correction. The number of random memories that a network can store is limited to a fraction of the number of electronic neurons in the circuit. We propose a method for building a hierarchy of networks that allows the fast parallel search through a list of memories that is too large to store in a single network. We have demonstrated the principle of this approach by an example in image vector quantization.
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Graf HP, Jackel LD, Howard RE, Straughn B, Denker JS, Hubbard W, Tennant DM, Schwartz D. VLSI implementation of a neural network memory with several hundreds of neurons. ACTA ACUST UNITED AC 1986. [DOI: 10.1063/1.36253] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Raisz LG, Dietrich JW, Simmons HA, Seyberth HW, Hubbard W, Oates JA. Effect of prostaglaidin endoperoxides and metabolites on bone resorption in vitro. Nature 1977; 267:532-4. [PMID: 876371 DOI: 10.1038/267532a0] [Citation(s) in RCA: 103] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Hurwitz L, Hubbard W, Little S. The relationship between the drug-receptor interaction and calcium transport in smooth muscle. J Pharmacol Exp Ther 1972; 183:117-26. [PMID: 5080027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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