342 results on '"M Stauber"'
Search Results
2. An Organometallic Gold(III) Reagent for
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James W, McDaniel, Julia M, Stauber, Evan A, Doud, Alexander M, Spokoyny, and Jennifer M, Murphy
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Fluorine Radioisotopes ,Isotope Labeling ,Gold ,Radiopharmaceuticals ,Peptides ,Sugars ,Article - Abstract
The (18)F-labeling of unprotected peptides and sugars with a Au(III)-[(18)F]fluoroaryl complex is reported. The chemoselective method generates (18)F-labeled S-aryl bioconjugates in an aqueous environment in 15 min with high radiochemical yields and displays excellent functional group tolerance. This approach utilizes an air and moisture stable, robust organometallic Au(III) complex and highlights the versatility of designer organometallic reagents as efficient agents for rapid radiolabeling.
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- 2023
3. An Organometallic Gold(III) Reagent for 18F Labeling of Unprotected Peptides and Sugars in Aqueous Media
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James W. McDaniel, Julia M. Stauber, Evan A. Doud, Alexander M. Spokoyny, and Jennifer M. Murphy
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Organic Chemistry ,Physical and Theoretical Chemistry ,Biochemistry - Published
- 2022
4. Programmable synthesis of well-defined, glycosylated iron(ii) supramolecular assemblies with multivalent protein-binding capabilities
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Jake H. Schwab, Jake B. Bailey, Milan Gembicky, and Julia M. Stauber
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Chemical Sciences ,General Chemistry ,Generic health relevance - Abstract
Multivalency plays a key role in achieving strong, yet reversible interactions in nature, and provides critical chemical organization in biological recognition processes. Chemists have taken an interest in designing multivalent synthetic assemblies to both better understand the underlying principles governing these interactions, and to build chemical tools that either enhance or prevent such recognition events from occurring in biology. Rationally tailoring synthetic strategies to achieve the high level of chemical control and tunability required to mimic these interactions, however, is challenging. Here, we introduce a systematic and modular synthetic approach to the design of well-defined molecular multivalent protein-binding constructs that allows for control over size, morphology, and valency. A series of supramolecular mono-, bi-, and tetrametallic Fe(ii) complexes featuring a precise display of peripheral saccharides was prepared through coordination-driven self-assembly from simple building blocks. The molecular assemblies are fully characterized, and we present the structural determination of one complex in the series. The mannose and maltose-appended assemblies display strong multivalent binding to model lectin, Concanavalin A (K d values in μM), where the strength of the binding is a direct consequence of the number of saccharide units decorating the molecular periphery. This versatile synthetic strategy provides chemical control while offering an easily accessible approach to examine important design principles governing structure-function relationships germane to biological recognition and binding properties.
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- 2023
5. Tuning counterion chemistry to reduce carrier localization in doped semiconducting carbon nanotube networks
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Tucker L. Murrey, Taylor J. Aubry, Omar Leon Ruiz, Kira A. Thurman, Klaus H. Eckstein, Evan A. Doud, Julia M. Stauber, Alexander M. Spokoyny, Benjamin J. Schwartz, Tobias Hertel, Jeffrey L. Blackburn, and Andrew J. Ferguson
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General Energy ,General Engineering ,General Physics and Astronomy ,General Materials Science ,General Chemistry - Published
- 2023
6. An Organometallic Strategy for Cysteine Borylation
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Mary A. Waddington, Alexander M. Spokoyny, Julia M. Stauber, Hayden R. Montgomery, Liban M. A. Saleh, Xin Zheng, Petr Král, and Elamar Hakim Moully
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Boron Compounds ,chemistry.chemical_classification ,Bioconjugation ,Molecular Structure ,Chemistry ,Peptide ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,Borylation ,Article ,Catalysis ,0104 chemical sciences ,Residue (chemistry) ,Colloid and Surface Chemistry ,DARPin ,Organometallic Compounds ,Moiety ,Cysteine ,Chemoselectivity ,Platinum - Abstract
Synthetic bioconjugation at cysteine (Cys) residues in peptides and proteins has emerged as a powerful tool in chemistry. Soft nucleophilicity of the sulfur in Cys renders an exquisite chemoselectivity with which various functional groups can be placed onto this residue under benign conditions. While a variety of reactions have been successful at producing Cys-based bioconjugates, the majority of these feature sulfur-carbon bonds. We report Cys-borylation, wherein a benchtop stable Pt(II)-based organometallic reagent can be used to transfer a boron-rich cluster onto a sulfur moiety in unprotected peptides forging a boron-sulfur bond. Cys-borylation proceeds at room temperature and tolerates a variety of functional groups present in complex polypeptides. Further, the bioconjugation strategy can be applied to a model protein modification of Cys-containing DARPin (designed ankyrin repeat protein). The resultant bioconjugates show no additional toxicity compared to their Cys alkyl-based congeners. Finally, we demonstrate how the developed Cys-borylation can enhance the proteolytic stability of the resultant peptide bioconjugates while maintaining the binding affinity to a protein target.
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- 2021
7. Dynamic Nuclear Polarization Using 3D Aromatic Boron Cluster Radicals
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Rebecca M. Kubena, Julia M. Stauber, Christian Hilty, Hamidreza Samouei, Pierce Pham, Alexander M. Spokoyny, Yaewon Kim, and Jonathan C. Axtell
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010304 chemical physics ,Chemistry ,Radical ,Dodecaborate ,chemistry.chemical_element ,Nuclear magnetic resonance spectroscopy ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Article ,0104 chemical sciences ,Delocalized electron ,0103 physical sciences ,Cluster (physics) ,General Materials Science ,Lewis acids and bases ,Physical and Theoretical Chemistry ,Boron ,Dissolution - Abstract
A set of two dodecaborate [B(12)(OR)(12)](1−) radical cluster anions containing a dense layer of fluorinated end-groups provide nuclear spin hyperpolarization via the dissolution dynamic nuclear polarization (D-DNP) technique. We show that these clusters can enhance (19)F nuclear magnetic resonance (NMR) signals. Importantly, given the inherent radical delocalization in dodecaborate-based radicals, these species are compatible with reactive compounds such as Lewis acids, providing ~ 1000 – 2000 times of signal enhancement for B(C(6)F(5))(3) in liquid state NMR experiments at 9.4 T. This observation suggests that 3D aromatic radicals can provide advantages over the conventional radical species that are currently used for DNP, such as 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) by showing superior chemical compatibility. The ability to hyperpolarize reactive compounds using [B(12)(OR)(12)](1−) cluster radicals opens up new applications of reaction monitoring by D-DNP NMR spectroscopy, including the observation of catalytically active species in complex reaction mixtures.
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- 2020
8. Tuning Counterion Chemistry to Reduce Carrier Localization in Doped Thermoelectric Carbon Nanotube Networks
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Tucker L. Murrey, Taylor J. Aubry, Omar Leon Ruiz, Kira A. Thurman, Klaus H. Eckstein, Evan A. Doud, Julia M. Stauber, Alexander M. Spokoyny, Benjamin J. Schwartz, Tobias Hertel, Jeff Blackburn, and Andrew John Ferguson
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2022
9. Electronic Structure of Superoxidized Radical Cationic Dodecaborate-Based Clusters
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Bo Li, Xinglong Zhang, Thomas F. Miller, Julia M. Stauber, and Alexander M. Spokoyny
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chemistry.chemical_classification ,Delocalized electron ,Partial charge ,chemistry.chemical_compound ,Computational chemistry ,Chemistry ,Aryl ,Dodecaborate ,Cationic polymerization ,Electronic structure ,Physical and Theoretical Chemistry ,Redox ,Alkyl - Abstract
The expanding field of boron clusters has attracted continuous theoretical efforts to understand their diverse structures and unique bonding. We recently discovered a new reversible redox event of B12(O-3-methylbutyl)12 in which the superoxidized radical cationic form [B12(O-3-methylbutyl)12]•+ was identified and isolated for the first time. Herein, comprehensive (TD-)DFT studies in tandem with electrochemical experiments were employed to demonstrate the generality of the reported behavior across perfunctionalized B12(OR)12 clusters (R = aryl or alkyl). While the spin density of radical cationic clusters is delocalized in the core region, the oxidation brings about notable gains of positive partial charges on the supporting groups whose electronics can readily tune the redox potential of the 0/•+ couple. The underlying changes of frontier orbitals were elucidated, and the resulting [B12(OR)12]•+ species manifest a general diagnostic absorption as a consequence of mixed local/charge-transfer excitations.
- Published
- 2021
10. Cysteine Borylation in Unprotected Peptides
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Petr Král, Mary A. Waddington, Liban M. A. Saleh, Alexander M. Spokoyny, Julia M. Stauber, ElamarHakim Moully, and Alice Zheng
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chemistry.chemical_classification ,Residue (chemistry) ,chemistry.chemical_compound ,Bioconjugation ,Chemistry ,Aryl ,Moiety ,Peptide ,Chemoselectivity ,Combinatorial chemistry ,Borylation ,Cysteine - Abstract
Synthetic bioconjugation at cysteine (Cys) residues in peptides and proteins has emerged as a powerful tool in chemistry. Soft nucleophilicity of the sulfur in Cys renders an exquisite chemoselectivity with which various functional groups can be placed onto this residue under benign conditions. While a variety of reactions have been successful at producing Cys-based bioconjugates, the majority of these feature sulfur-carbon bonds. We report Cys-borylation, wherein a benchtop stable Pt(II)-based organometallic reagent can be used to transfer a boron-rich cluster onto a sulfur moiety in unprotected peptides forging a boron-sulfur bond. Discovered Cysborylation proceeds at room temperature and is tolerant to a variety of functional groups present in complex polypeptides. The resultant bioconjugates show no additional toxicity compared to their Cys aryl-based congeners. Finally, we demonstrate how the developed Cys-borylation can enhance the proteolytic stability of the produced peptide bioconjugates while maintaining the binding affinity to a protein target.
- Published
- 2021
11. Gold(III) Aryl Complexes as Reagents for Constructing Hybrid Peptide-Based Assemblies via Cysteine S-Arylation
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Julia M. Stauber, Alexander M. Spokoyny, and Arnold L. Rheingold
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chemistry.chemical_classification ,Bioconjugation ,Molecular Structure ,Bicyclic molecule ,Biomolecule ,Aryl ,Peptide ,Combinatorial chemistry ,Article ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Covalent bond ,Functional group ,Indicators and Reagents ,Cysteine ,Physical and Theoretical Chemistry ,Chemoselectivity ,Peptides ,Organogold Compounds - Abstract
Organometallic complexes have recently gained attention as competent bioconjugation reagents capable of introducing a diverse array of substrates to biomolecule substrates. Here, we detail the synthesis and characterization of an aminophosphine-supported Au(III) platform that provides rapid and convenient access to a wide array of peptide-based assemblies via cysteine S-arylation. This strategy results in the formation of robust C‒S covalent linkages and is an attractive method for the modification of complex biomolecules due to the high functional group tolerance, chemoselectivity, and rapid reaction kinetics associated with these arylation reactions. This work expands upon existing metal-mediated cysteine arylation by introducing a class of air-stable organometallic complexes that serve as competent bioconjugation reagents enabling the synthesis of conjugates of higher structural complexity including macrocyclic stapled and bicyclic peptides, as well as a peptide-functionalized multivalent hybrid nanocluster. This organometallic-based approach provides a convenient, one-step method of peptide functionalization and macrocyclization, and has the potential to contribute to efforts directed towards developing efficient synthetic strategies of building new and diverse hybrid peptide-based assemblies of high complexit
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- 2020
12. Tunable Dopants with Intrinsic Counterion Separation Reveal the Effects of Electron Affinity on Dopant Intercalation and Free Carrier Production in Sequentially Doped Conjugated Polymer Films
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Taylor J. Aubry, Victoria M. Basile, Charlene Z. Salamat, Sarah H. Tolbert, Benjamin J. Schwartz, Alexander M. Spokoyny, Matthew J. Bird, Minh Dinh Phan, K. J. Winchell, Julia M. Stauber, Rebecca M. Kubena, Jonathan C. Axtell, and Jeffrey Lindemuth
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inorganic chemicals ,Electron mobility ,Materials science ,02 engineering and technology ,010402 general chemistry ,Polaron ,01 natural sciences ,counterion distance ,Biomaterials ,Engineering ,redox‐driven infiltration ,Electron affinity ,molecular dopants ,Electrochemistry ,Materials ,tunable electron affinity ,redox-driven infiltration ,chemistry.chemical_classification ,Dopant ,doping efficiency ,electronic offset ,semiconducting polymers ,Doping ,Polymer ,Full Papers ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,chemistry ,Chemical physics ,Physical Sciences ,Chemical Sciences ,Neutron reflectometry ,Counterion ,0210 nano-technology - Abstract
Carrier mobility in doped conjugated polymers is limited by Coulomb interactions with dopant counterions. This complicates studying the effect of the dopant's oxidation potential on carrier generation because different dopants have different Coulomb interactions with polarons on the polymer backbone. Here, dodecaborane (DDB)‐based dopants are used, which electrostatically shield counterions from carriers and have tunable redox potentials at constant size and shape. DDB dopants produce mobile carriers due to spatial separation of the counterion, and those with greater energetic offsets produce more carriers. Neutron reflectometry indicates that dopant infiltration into conjugated polymer films is redox‐potential‐driven. Remarkably, X‐ray scattering shows that despite their large 2‐nm size, DDBs intercalate into the crystalline polymer lamellae like small molecules, indicating that this is the preferred location for dopants of any size. These findings elucidate why doping conjugated polymers usually produces integer, rather than partial charge transfer: dopant counterions effectively intercalate into the lamellae, far from the polarons on the polymer backbone. Finally, it is shown that the IR spectrum provides a simple way to determine polaron mobility. Overall, higher oxidation potentials lead to higher doping efficiencies, with values reaching 100% for driving forces sufficient to dope poorly crystalline regions of the film.
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- 2020
13. A Super-Oxidized Radical Cationic Icosahedral Boron Cluster
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Andrew J. Martinolich, Kimberly A. See, Paul H. Oyala, Julia M. Stauber, Thomas F. Miller, Dahee Jung, Brendon J. McNicholas, Harry B. Gray, Josef Schwan, Xinglong Zhang, Alexander M. Spokoyny, Jonathan C. Axtell, and Jay R. Winkler
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Icosahedral symmetry ,Chemistry ,Substitution (logic) ,Cationic polymerization ,chemistry.chemical_element ,General Chemistry ,Electrochemistry ,Redox ,Biochemistry ,Catalysis ,law.invention ,Delocalized electron ,chemistry.chemical_compound ,Crystallography ,Colloid and Surface Chemistry ,Unpaired electron ,Ferrocene ,Radical ion ,law ,Alkoxy group ,Cluster (physics) ,Electron paramagnetic resonance ,Boron - Abstract
While the icosahedral closo-[B12H12]2– cluster does not display reversible electrochemical behavior, perfunctionalization of this species via substitution of all twelve B–H vertices with alkoxy orbenzyloxy (OR) substituents engenders reversible redox chemistry, providing access to clusters in the dianionic,monoanionic, and neutral forms. Here, we evaluated the electrochemical behavior of the electron-rich B12(O-3-methylbutyl)12 (1) cluster and discovered that a new reversible redox event that gives rise to a fourth electronic state is accessible through one-electron oxidation of the neutral species. Chemical oxidation of 1 with [N(2,4-Br2C6H3)3]•+ afforded the isolable[1] •+ cluster, which is the first example of an open-shell cationic B12 cluster in which the unpaired electron is proposed to be delocalized throughout the boron cluster core. The oxidation of 1 is also chemically reversible, where treatment of [1]•+ with ferrocene resulted in its reduction back to 1. The identity of [1]•+ is supported by EPR, UV-vis, multinuclear NMR (1H, 11B), and X-ray photoelectron spectroscopic characterization.
- Published
- 2020
14. A molecular boron cluster-based chromophore with dual emission
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Mary A. Waddington, Nicholas A. Bernier, Kierstyn P. Anderson, Gary J. Balaich, Julia M. Stauber, Justin R. Caram, Alexander M. Spokoyny, and Peter I. Djurovich
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Cyclohexane ,010405 organic chemistry ,Chemistry ,Chromophore ,Borane ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Fluorescence ,0104 chemical sciences ,Inorganic Chemistry ,Electrophilic substitution ,chemistry.chemical_compound ,Molecule ,Phosphorescence ,Luminescence - Abstract
Bromination of the luminescent borane, anti-B18H22, via electrophilic substitution using AlCl3 and Br2, yields the monosubstituted derivative 4-Br-anti-B18H21 as an air-stable crystalline solid. In contrast to the unsubstituted parent compound, 4-Br-anti-B18H21 possesses dual emission upon excitation with UV light and exhibits fluorescence at 410 nm and phosphorescence at 503 nm, with Φtotal = 0.07 in oxygen-free cyclohexane. Increased oxygen content in cyclohexane solution quenches the phosphorescence signal. The fluorescent signal intensity remains unaffected by oxygen, suggesting that this molecule could be used as a ratiometric oxygen probe.
- Published
- 2020
15. Retraction of 'Pushing Single-Oxygen-Atom-Bridged Bimetallic Systems to the Right: A Cryptand-Encapsulated Co-O-Co Unit'
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Christopher C. Cummins, Laura Gagliardi, Julia M. Stauber, Shao-Liang Zheng, Dugan Hayes, Ryan G. Hadt, Eric D. Bloch, Lin X. Chen, Konstantinos D. Vogiatzis, and Daniel G. Nocera
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Absorption spectroscopy ,Ligand ,Cryptand ,General Chemistry ,Biochemistry ,Catalysis ,Ion ,Crystallography ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,chemistry ,Oxidation state ,Complete active space ,Bimetallic strip ,Potassium superoxide - Abstract
A dicobalt(II) complex, [Co2(mBDCA-5t)](2-) (1), demonstrates a cofacial arrangement of trigonal monopyramidal Co(II) ions with an inter-metal separation of 6.2710(6) A. Reaction of 1 with potassium superoxide generates an encapsulated Co-O-Co core in the dianionic complex, [Co2O(mBDCA-5t)](2-) (2); to form the linear Co-O-Co core, the inter-metal distance has diminished to 3.994(3) A. Co K-edge X-ray absorption spectroscopy data are consistent with a +2 oxidation state assignment for Co in both 1 and 2. Multireference complete active space calculations followed by second-order perturbation theory support this assignment, with hole equivalents residing on the bridging O-atom and on the cryptand ligand for the case of 2. Complex 2 acts as a 2-e(-) oxidant toward substrates including CO and H2, in both cases efficiently regenerating 1 in what represent net oxygen-atom-transfer reactions. This dicobalt system also functions as a catalase upon treatment with H2O2.
- Published
- 2020
16. A Molecular Boron Cluster-Based Chromophore with Dual Emission
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PeterI. Djurovich, Gary J. Balaich, JustinR. Caram, Kierstyn P. Anderson, Mary A. Waddington, Julia M. Stauber, and Alexander M. Spokoyny
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chemistry.chemical_compound ,Electrophilic substitution ,chemistry ,Cyclohexane ,Molecule ,Borane ,Chromophore ,Luminescence ,Photochemistry ,Phosphorescence ,Fluorescence - Abstract
Bromination of the luminescent borane, anti-B18H22, via electrophilic substitution using AlCl3 and Br2 yields the monosubstituted derivative 4-Br-anti-B18H21 as an air-stable crystalline solid. In contrast to the unsubstituted parent compound, 4-Br-anti-B18H21 product possesses dual emission upon excitation with UV light and exhibits fluorescence at 410 nm and phosphorescence at 503 nm, with Фtotal = 0.07 in oxygen-free cyclohexane. Increased oxygen content in cyclohexane solution quenches the phosphorescence signal. The fluorescent signal intensity remains unaffected by oxygen, suggesting that this molecule could be used as a ratiometric oxygen probe.
- Published
- 2020
17. A Molecular Boron Cluster-Based Chromophore with Dual Emission
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Alexander Spokoyny, Peter I. Djurovich, Justin R. Caram, Julia M. Stauber, Gary J. Balaich, Mary A. Waddington, and Kierstyn P. Anderson
- Abstract
Bromination of the luminescent borane, anti-B18H22, via electrophilic substitution using AlCl3 and Br2 yields the monosubstituted derivative 4-Br-anti-B18H21 as an air-stable crystalline solid. In contrast to the unsubstituted parent compound, 4-Br-anti-B18H21 product possesses dual emission upon excitation with UV light and exhibits fluorescence at 410 nm and phosphorescence at 503 nm, with Фtotal = 0.07 in oxygen-free cyclohexane. Increased oxygen content in cyclohexane solution quenches the phosphorescence signal. The fluorescent signal intensity remains unaffected by oxygen, suggesting that this molecule could be used as a ratiometric oxygen probe.
- Published
- 2020
18. Second-Coordination-Sphere Assisted Selective Colorimetric Turn-on Fluoride Sensing by a Mono-Metallic Co(II) Hexacarboxamide Cryptand Complex
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Christopher C. Cummins, Julia M. Stauber, Glen E. Alliger, and Daniel G. Nocera
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Aqueous solution ,Coordination sphere ,010405 organic chemistry ,medicine.drug_class ,Cryptand ,Inorganic chemistry ,chemistry.chemical_element ,Carboxamide ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,Metal ,chemistry.chemical_compound ,chemistry ,visual_art ,medicine ,visual_art.visual_art_medium ,Physical and Theoretical Chemistry ,Cobalt ,Single crystal ,Fluoride - Abstract
The preparation of a selective turn-on colorimetric fluoride sensor was achieved through single cobalt(II) ion insertion into a macrobicyclic cryptand. Monometallic [Co(mBDCA-5t-H3)]− (1) and [Zn(mBDCA-5t-H3)]− (2) complexes were prepared in 74 and 84% yields, respectively. Structural characterization of 1 confirmed the presence of a proximal hydrogen-bonding network consisting of carboxamide N–H donors. The reaction of 1 with F– was accompanied by a distinct colorimetric turn-on response in mixed aqueous/organic media, and 1 was capable of selective fluoride sensing in the presence of large quantities of potentially competitive anions. Complex 1 represents a unique example of a fluoride sensor wherein selective F– binding takes place directly at a transition-metal center and induces a color change based upon metal-centered transitions. The metal(II) fluoride complexes [F⊂Co(mBDCA-5t-H3)]2– (3) and [F⊂Zn(mBDCA-5t-H3)]2– (4) were both fully characterized, including single crystal X-ray analyses. Fluoride b...
- Published
- 2017
19. Synthetic and Mechanistic Interrogation of Pd/Isocyanide-Catalyzed Cross-Coupling: π-Acidic Ligands Enable Self-Aggregating Monoligated Pd(0) Intermediates
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Brandon R. Barnett, Curtis E. Moore, Arnold L. Rheingold, Julia M. Stauber, Joshua S. Figueroa, and Liezel A. Labios
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chemistry.chemical_classification ,Base (chemistry) ,010405 organic chemistry ,Stereochemistry ,Aryl ,Isocyanide ,Organic Chemistry ,010402 general chemistry ,01 natural sciences ,Oxidative addition ,Combinatorial chemistry ,0104 chemical sciences ,Catalysis ,Inorganic Chemistry ,Coupling (electronics) ,chemistry.chemical_compound ,chemistry ,Bromide ,Alkoxide ,Physical and Theoretical Chemistry - Abstract
Despite the large number of judiciously designed ligands that have been exploited in palladium-catalyzed cross-coupling protocols, the incorporation of ligands bearing appreciable π-acidic properties has remained significantly underexplored. Herein, we demonstrate that well-defined and low-coordinate Pd0 complexes supported by m-terphenyl isocyanides function as competent catalysts for the Suzuki–Miyaura cross-coupling of aryl bromides and arylboronic acids. Two-coordinate Pd(CNArDipp2)2 was active for the coupling of unhindered aryl bromides at room temperature in 2-propanol, while increasing the temperature to 60 °C allowed for the use of mono- or di-ortho-substituted aryl bromides. Oxidative addition of the aryl bromide was shown to proceed via a dissociative mechanism, implicating monoligated Pd(CNArDipp2) as the catalytically active intermediate. Attempts to access this fleeting species via activation of the PdII monoisocyanide PdCl(η3-C3H5)(CNArDipp2) with alkoxide base yielded the dinuclear PdI spe...
- Published
- 2017
20. An Organometallic Strategy for Assembling Atomically Precise Hybrid Nanomaterials
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Daishi Fujita, Arnold L. Rheingold, Yanxiao Han, Petr Král, Julia M. Stauber, Elaine A. Qian, and Alexander M. Spokoyny
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Spectrometry, Mass, Electrospray Ionization ,Magnetic Resonance Spectroscopy ,Materials science ,Metal Nanoparticles ,Nanotechnology ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Catalysis ,Article ,Nanomaterials ,Nanoclusters ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Organometallic Compounds ,Cluster (physics) ,Systematic synthesis ,Organometallic chemistry ,Extramural ,General Chemistry ,0104 chemical sciences ,chemistry ,Complex protein ,Colloidal gold ,Gold ,Multivalent binding - Abstract
For decades, chemists have strived to mimic the intricate design and diverse functions of naturally occurring systems through the bioinspired synthesis of programmable inorganic nanomaterials. The development of thiol-capped gold nanoparticles (AuNPs) has driven advancement in this area; however, although versatile and readily accessible, hybrid AuNPs are rarely atomically precise, which limits control over their surface topology and therefore the study of complex structure-function relationships. Here, we present a bottom-up approach to the systematic assembly of atomically precise hybrid nanoclusters employing a strategy that mimics the synthetic ease with which thiol-capped AuNPs are normally constructed, while producing welldefined covalent nanoscale assemblies with diverse surface topologies. For the first time, using a structurally characterized cluster-based organometallic building block, we demonstrate the systematic synthesis of nanoclusters with multivalent binding capabilities to complex protein targets.
- Published
- 2019
21. Crystalline Metaphosphate Acid Salts: Synthesis in Organic Media, Structures, Hydrogen-Bonding Capability, and Implication of Superacidity
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Khetpakorn Chakarawet, Matthew Nava, Julia M. Stauber, Ioana Knopf, Yanfeng Jiang, and Christopher C. Cummins
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010405 organic chemistry ,Hydrogen bond ,Metaphosphate ,Inorganic chemistry ,Protonation ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,Pyrophosphate ,0104 chemical sciences ,Inorganic Chemistry ,Solvent ,chemistry.chemical_compound ,Hydrolysis ,chemistry ,Intramolecular force ,Yield (chemistry) ,Physical and Theoretical Chemistry - Abstract
Metaphosphate acids cannot be thoroughly studied in aqueous media because their acidity is leveled by the solvent, and the resulting metaphosphates are susceptible to acid-catalyzed hydrolysis. Exploration of metaphosphate acid chemistry has now been made possible with the development of a general synthetic method for organic media soluble metaphosphate acids. Protonation of the [PPN](+) salts ([PPN](+) = [N(PPh3)2](+)) of tri-, tetra-, and hexametaphosphates results in five new metaphosphate acids, [PPN]2[P3O9H] (2), [PPN]4[(P4O12)3H8] (3), [PPN]4[P6O18H2]·2H2O (4), [PPN]3[P6O18H3] (5), and [PPN]2[P6O18H2(H3O)2] (6), obtained in yields of 80, 71, 66, 88, and 76%, respectively. Additionally, our synthetic method can be extended to pyrophosphate to produce [PPN][P2O7H3] (7) in 77% yield. The structural configurations of these oxoacids are dictated by strong hydrogen bonds and the anticooperative effect. Intramolecular hydrogen bonds are observed in 2, 4, and 5 and the previously reported [PPN]2[P4O12H2] (1), while intermolecular hydrogen bonds are observed in 3, 6, and 7. The hydrogen bonds in 3-7 possess short distances and are classified as low-barrier hydrogen bonds. Gas-phase acidity computations reveal that the parent tri- and tetrametaphosphoric acids are superacids. Their remarkable acidity is attributable to the stabilization of their corresponding conjugate bases via intramolecular hydrogen bonding.
- Published
- 2016
22. Multi-electron reactivity of a cofacial di-tin(<scp>ii</scp>) cryptand: partial reduction of sulfur and selenium and reversible generation of S3˙−
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Peter Müller, Gang Wu, Yizhe Dai, Daniel G. Nocera, Julia M. Stauber, Christopher C. Cummins, Institute for Medical Engineering and Science, Massachusetts Institute of Technology. Department of Biology, Massachusetts Institute of Technology. Department of Chemical Engineering, Massachusetts Institute of Technology. Department of Chemistry, Stauber, Julia M., Miller, Peter G, and Nocera, Daniel G
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010405 organic chemistry ,Chemistry ,Cryptand ,Inorganic chemistry ,chemistry.chemical_element ,General Chemistry ,Electron ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,Sulfur ,0104 chemical sciences ,Chalcogen ,SN2 reaction ,Tin ,Bimetallic strip ,Selenium - Abstract
Cofacial bimetallic tin( II ) ([Sn 2 ( m BDCA-5t)] 2-, 1) and lead( II ) ([Pb₂(mBDCA-5t)]²-, 2) complexes have been prepared by hexadeprotonation of hexacarboxamide cryptand m BDCA-5t-H₆ together with double Sn(II) or Pb(II) insertion. Reaction of 1 with elemental sulfur or selenium generates di-tin polychalcogenide complexes containing m -E and bridging m -E 5 ligands where E ¼ S or Se, and the Sn( II ) centers have both been oxidized to Sn( IV ). Solution and solid-state UV-Vis spectra of [( m -S 5 )Sn 2 ( m -S)( m BDCA-5t)] 2 ( 4 ) indicate that the complex acts reversibly as a source of S 3 c in DMF solution with a K eq ¼ 0.012 0.002. Reductive removal of all six chalcogen atoms is achieved through treatment of [( m -E 5 )Sn 2 ( m -E)( m BDCA- 5t)] 2 with PR 3 (R ¼ t Bu, Ph, O i Pr) to produce six equiv. of the corresponding EPR 3 compound with regeneration of di-tin( II ) cryptand complex 1., National Science Foundation (U.S.) (CHE-1305124)
- Published
- 2016
23. Cobalt and Vanadium Trimetaphosphate Polyanions: Synthesis, Characterization, and Electrochemical Evaluation for Non-aqueous Redox-Flow Battery Applications
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Julia M. Stauber, Shiyu Zhang, Keith J. Stevenson, Nataliya A. Gvozdik, Yanfeng Jiang, Laura Avena, and Christopher C. Cummins
- Subjects
Aqueous solution ,chemistry.chemical_element ,Vanadium ,Infrared spectroscopy ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Biochemistry ,Redox ,Catalysis ,0104 chemical sciences ,Electrochemical cell ,Colloid and Surface Chemistry ,chemistry ,0210 nano-technology ,Cobalt ,Nuclear chemistry ,Monoclinic crystal system - Abstract
An electrochemical cell consisting of cobalt ([CoII/III(P3O9)2]4–/3–) and vanadium ([VIII/II(P3O9)2]3–/4–) bistrimetaphosphate complexes as catholyte and anolyte species, respectively, was constructed with a cell voltage of 2.4 V and Coulombic efficiencies >90% for up to 100 total cycles. The [Co(P3O9)2]4– (1) and [V(P3O9)2]3– (2) complexes have favorable properties for flow-battery applications, including reversible redox chemistry, high stability toward electrochemical cycling, and high solubility in MeCN (1.09 ± 0.02 M, [PPN]4[1]·2MeCN; 0.77 ± 0.06 M, [PPN]3[2]·DME). The [PPN]4[1]·2MeCN and [PPN]3[2]·DME salts were isolated as crystalline solids in 82 and 68% yields, respectively, and characterized by 31P NMR, UV/vis, ESI-MS(−), and IR spectroscopy. The [PPN]4[1]·2MeCN salt was also structurally characterized, crystallizing in the monoclinic P21/c space group. Treatment of 1 with [(p-BrC6H4)3N]+ allowed for isolation of the one-electron-oxidized spin-crossover (SCO) complex, [Co(P3O9)2]3– (3), which is...
- Published
- 2017
24. Spinal neuronal activation during locomotor-like activity enabled by epidural stimulation and 5-hydroxytryptamine agonists in spinal rats
- Author
-
Trinh T. Pham, Roland R. Roy, Mei Si Xiao, Paul O. Duru, Hui Zhong, Niranjala J.K. Tillakaratne, Jung A. Kim, Stacey M. Stauber, and V. Reggie Edgerton
- Subjects
Agonist ,education.field_of_study ,medicine.drug_class ,business.industry ,Quipazine ,education ,Population ,Stimulation ,Serotonergic ,Cellular and Molecular Neuroscience ,Lumbar Spinal Cord ,Lumbar ,medicine ,Cholinergic ,business ,Neuroscience ,medicine.drug - Abstract
The neural networks that generate stepping in complete spinal adult rats remain poorly defined. To address this problem we used c-fos (an activity-dependent marker) to identify active interneurons and motoneurons in the lumbar spinal cord of adult spinal rats during a 30-minute bout of bipedal stepping. Spinal rats were either step trained (30 min/day, 3 days/week for 7.5 weeks) or not step-trained. Stepping was enabled by epidural stimulation and the administration of the serotonergic agonists quipazine and 8-OHDPAT. A third group of spinal rats served as untreated (no stimulation, drugs, or stepping) controls. The number of activated cholinergic central canal cluster cells and partition neurons was higher in both step-trained and non-trained than untreated rats, and higher in non-trained than step-trained rats. The latter finding suggests that daily treatment with epidural stimulation plus serotonergic agonist treatment without step training enhanced the excitability of a broader cholinergic interneuronal population than step training. The number of activated interneurons in laminae II-VI of lumbar cross sections was higher in both step-trained and non-trained than untreated rats, and highest in step-trained rats. This finding suggests that this population of interneurons was responsive to epidural stimulation plus serotonergic treatment and that load-bearing induced when stepping had an additive effect. The number of activated motoneurons of all size categories was higher in the step-trained than the other two groups, reflecting a strong effect of loading on motoneuron recruitment. In general, these results indicate that the spinal networks for locomotion are similar with and without brain input.
- Published
- 2015
25. Terminal Titanyl Complexes of Tri- and Tetrametaphosphate: Synthesis, Structures, and Reactivity with Hydrogen Peroxide
- Author
-
Julia M. Stauber and Christopher C. Cummins
- Subjects
010405 organic chemistry ,Stereochemistry ,Metaphosphate ,Dimer ,Space group ,Triclinic crystal system ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Yield (chemistry) ,Reactivity (chemistry) ,Physical and Theoretical Chemistry ,Hydrogen peroxide ,Monoclinic crystal system - Abstract
The synthesis and characterization of tri- and tetrametaphosphate titanium(IV) oxo and peroxo complexes is described. Addition of 0.5 equiv of [OTi(acac)2]2 to dihydrogen tetrametaphosphate ([P4O12H2]2–) and monohydrogen trimetaphosphate ([P3O9H]2–) provided a bis(μ2,κ2,κ2) tetrametaphosphate titanyl dimer, [OTiP4O12]24– (1; 70% yield), and a trimetaphosphate titanyl acetylacetonate complex, [OTiP3O9(acac)]2– (2; 59% yield). Both 1 and 2 have been structurally characterized, crystallizing in the triclinic P1 and monoclinic P21 space groups, respectively. These complexes contain Ti≡O units with distances of 1.624(7) and 1.644(2) A, respectively, and represent rare examples of structurally characterized terminal titanyls within an all-oxygen coordination environment. Complexes 1 and 2 react with hydrogen peroxide to produce the corresponding peroxotitanium(IV) metaphosphate complexes [O2TiP4O12]24–(3; 61% yield) and [O2TiP3O9(acac)]2– (4; 65% yield), respectively. Both 3 and 4 have been characterized by si...
- Published
- 2017
26. A new method for preparing tannin-based foams
- Author
-
Alain Celzard, Vanessa Fierro, M. Stauber, A. Szczurek, Antonio Pizzi, Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude et de Recherche sur le Matériau Bois (LERMAB), Université de Lorraine (UL), and King Abdulaziz University
- Subjects
Materials science ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,[SPI.MAT]Engineering Sciences [physics]/Materials ,Pulmonary surfactant ,[SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph] ,Mechanical strength ,Tannin ,Porosity ,Curing (chemistry) ,[SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph] ,chemistry.chemical_classification ,[CHIM.MATE]Chemical Sciences/Material chemistry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism ,[CHIM.POLY]Chemical Sciences/Polymers ,chemistry ,Chemical engineering ,[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] ,[SPI.MECA.THER]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Thermics [physics.class-ph] ,Condensed tannin ,Aeration ,0210 nano-technology ,Agronomy and Crop Science - Abstract
International audience; Phenolic foams derived from natural precursors, condensed tannin extracts from mimosa trees, were prepared for the first time by curing and drying liquid foams obtained by aeration of tannin solutions containing surfactant and crosslinker. The materials derived from the new method were called tannin-based meringues in reference to the lightweight pastry made in a similar way by whipping egg whites. The new foams were compared with more standard cellular solids having very close composition but obtained by physical or chemical foaming. No significant differences were observed in terms of mechanical and thermal properties. The porous structure was also similar, except the cell sizes which were much higher in tannin-based meringues. The new method is not only easy, fast and cost-effective, but allows producing solid foams having a very broad range of bulk densities and cell sizes, which can be controlled by the concentration of tannin in the initial solution, all other things being equal.
- Published
- 2014
27. Effects of the Space Environment on Space-Based Radar Phased-Array Antenna; Status and Preliminary Observations (LDEF Experiment A0133)
- Author
-
J B Whiteside, D Giangano, R L Heuer, E Kamykowski, M Kesselman, W D Rooney, R Schulte, and M Stauber
- Subjects
Nonmetallic Materials - Abstract
The overall objective of the experiment was to evaluate the effect of the space environment on components considered for a Space-Based Radar (SBR) Phased-Array Antenna. Of primary interest was a study of the degradation of the polyimide film Kapton (DuPont trademark), the material considered for use in the antenna plane. The most striking result of the experiment was the overall good condition of the Kapton antenna planes and Kapton tensile specimens, despite nearly six years of exposure to the space environment. This was largely attributable to the orientation of the Kapton (parallel and flush on the space end) and the stability of the Long Duration Exposure Facility (LDEF) in orbit. However, weathering of exposed Kapton surfaces was not insignificant. Results on elongation and mechanical properties of the plain and the fiberglass-reinforced Kapton are presented. Reduction in strain to failure of flight-exposed Kapton is attributed to surface defects of these specimens. Physical property testing of the materials to date reveals no significant difference between flight-exposed and control material. The second objective was to investigate the interaction between high-voltage electrodes and typical spacecraft contaminants in simulation of discharge triggering across differentially charged dielectric surfaces (spacecraft charging conditions). Electronic data acquisition and memory systems appeared to operate correctly, but very few discharges were recorded. Induced radioactivity, contamination, impacts, and orientation features of atomic oxygen erosion were observed.
- Published
- 1992
28. Carbon meringues derived from flavonoid tannins
- Author
-
Antonio Pizzi, A. Szczurek, M. Stauber, Alain Celzard, Vanessa Fierro, Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude et de Recherche sur le Matériau Bois (LERMAB), Université de Lorraine (UL), Ecole Nationale Supérieure des Technologies et Industries du Bois (ENSTIB), and King Abdulaziz University
- Subjects
Materials science ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,[SPI.MAT]Engineering Sciences [physics]/Materials ,Adsorption ,Thermal conductivity ,[SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph] ,Tannin ,General Materials Science ,Composite material ,Porosity ,[SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph] ,chemistry.chemical_classification ,Aqueous solution ,[CHIM.MATE]Chemical Sciences/Material chemistry ,General Chemistry ,Porosimetry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism ,[CHIM.POLY]Chemical Sciences/Polymers ,chemistry ,Homogeneous ,[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] ,[SPI.MECA.THER]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Thermics [physics.class-ph] ,0210 nano-technology ,Carbon - Abstract
International audience; New macro-cellular carbons, called carbon meringues, have been prepared by whipping until stiff an aqueous solution of tannin until liquid foam was obtained, which was next stabilized in an oven and pyrolysed, hence their name. With such cheap, fast and very easy process, flawless, homogeneous carbon foams were obtained in a wider range of density than that of more conventional cellular vitreous carbon (CVC) foams derived from similar formulations but made by physical foaming. The porosity, the average cell size and the cell wall thickness were only controlled by the initial concentration of tannin, all other things being equal. The resultant carbon meringues were fully investigated by electron microscopy, X-ray tomography, mercury porosimetry, Kr and N-2 adsorption, thermal conductivity and mechanical compression studies. Differences with former CVC foams, and advantages of the new process and materials have been emphasised.
- Published
- 2013
29. Off-Axis Vs. on-Axis Training of Laparoscopic Skills
- Author
-
M. Stauber, M. Nimaroff, and B.S. Abittan
- Subjects
medicine.medical_specialty ,business.industry ,Training (meteorology) ,Physical therapy ,medicine ,Obstetrics and Gynecology ,business - Published
- 2017
30. Raman spectroscopy and microspectrophotometry of reactive dyes on cotton fibres: Analysis and detection limits
- Author
-
Z. Van Zanten, S. Chabli, Geneviève Massonnet, T. Sauneuf, C. Meile, T. Coyle, A. Blumer, Claude Roux, Steven E. J. Bell, M. Stauber, Louise A. Fido, Kenneth G. Wiggins, F. Monard, C. Smith, S. Ketterer, Avner Rosengarten, J. Hemmings, H. Leijenhorst, Patrick Buzzini, and G. Jochem
- Subjects
Detection limit ,Blue dye ,Chemistry ,Analytical chemistry ,Laser ,Pathology and Forensic Medicine ,law.invention ,symbols.namesake ,chemistry.chemical_compound ,Wavelength ,law ,Microscopy ,symbols ,Reactive dye ,Legal & Forensic Medicine ,Raman spectroscopy ,Law ,Chemical composition - Abstract
A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w).This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength.Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy.This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture. © 2012 Elsevier Ireland Ltd.
- Published
- 2012
31. Pushing Single-Oxygen-Atom-Bridged Bimetallic Systems to the Right: A Cryptand-Encapsulated Co-O-Co Unit
- Author
-
Julia M. Stauber, Shao-Liang Zheng, Daniel G. Nocera, Dugan Hayes, Konstantinos D. Vogiatzis, Lin X. Chen, Eric D. Bloch, Laura Gagliardi, Christopher C. Cummins, and Ryan G. Hadt
- Subjects
Absorption spectroscopy ,Cryptand ,Nanotechnology ,General Chemistry ,Biochemistry ,Catalysis ,Ion ,chemistry.chemical_compound ,Crystallography ,Colloid and Surface Chemistry ,Oxygen atom ,chemistry ,Oxidation state ,Complete active space ,Bimetallic strip ,Potassium superoxide - Abstract
A dicobalt(II) complex, [Co2(mBDCA-5t)](2-) (1), demonstrates a cofacial arrangement of trigonal monopyramidal Co(II) ions with an inter-metal separation of 6.2710(6) A. Reaction of 1 with potassium superoxide generates an encapsulated Co-O-Co core in the dianionic complex, [Co2O(mBDCA-5t)](2-) (2); to form the linear Co-O-Co core, the inter-metal distance has diminished to 3.994(3) A. Co K-edge X-ray absorption spectroscopy data are consistent with a +2 oxidation state assignment for Co in both 1 and 2. Multireference complete active space calculations followed by second-order perturbation theory support this assignment, with hole equivalents residing on the bridging O-atom and on the cryptand ligand for the case of 2. Complex 2 acts as a 2-e(-) oxidant toward substrates including CO and H2, in both cases efficiently regenerating 1 in what represent net oxygen-atom-transfer reactions. This dicobalt system also functions as a catalase upon treatment with H2O2.
- Published
- 2015
32. Portable Virtual Reality Laparoscopic Trainer to Incentivize Surgical Education
- Author
-
M. Stauber, M. Nimaroff, and B.S. Abittan
- Subjects
Medical education ,Multimedia ,business.industry ,Trainer ,Obstetrics and Gynecology ,Medicine ,Surgical education ,Virtual reality ,computer.software_genre ,business ,computer - Published
- 2017
33. 17. Psychosomatik in Geburtshilfe und Gynäkologie
- Author
-
M. Stauber
- Published
- 2015
34. Prognosis of Low-Risk Young Women Presenting to the Emergency Department With Chest Pain
- Author
-
Ezra A. Amsterdam, Aleksander Teleten, Sandhya Venugopal, Stacey M. Stauber, and Zhongmin Li
- Subjects
Adult ,medicine.medical_specialty ,Cardiac Catheterization ,Chest Pain ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Chest pain ,03 medical and health sciences ,Electrocardiography ,0302 clinical medicine ,Risk Factors ,Internal medicine ,Clinical endpoint ,Medicine ,Humans ,030212 general & internal medicine ,Treadmill ,Cardiac catheterization ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Retrospective cohort study ,Emergency department ,Middle Aged ,Prognosis ,Hospitalization ,Anesthesia ,Cohort ,Physical therapy ,Cardiology ,Exercise Test ,Female ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Emergency Service, Hospital - Abstract
Identification of patients at low risk presenting to the emergency department with chest pain is a continuing challenge. We examined a cohort of low-risk women with negative cardiac injury markers, electrocardiogram with normal results, and clinical stability. We hypothesized that these patients can be safely and accurately managed in a chest pain unit (CPU), may not require predischarge cardiac testing, and have an excellent short-term prognosis. The primary end point was major cardiovascular events during index admission or follow-up. Mean age of the 403 women was 42 ± 4.3 years (30 to 50 years). No patient had a cardiovascular event in the CPU, and none of the 321 patients followed for 6 months had a late cardiovascular event. Most (211, 52%) did not receive predischarge cardiac testing. The remaining 192 patients (48%) had predischarge exercise treadmill test, stress imaging, or cardiac catheterization. Of those patients who underwent treadmill testing, almost 90% had no exercise-induced chest pain and approximately 50% had functional capacity 8 to 14 METs. In addition, 166 patients (41%) were discharged from the CPU after
- Published
- 2015
35. Evaporation of droplets on strongly hydrophobic substrates
- Author
-
Stephen Wilson, Brian R. Duffy, Khellil Sefiane, and Jutta M. Stauber
- Subjects
FLOW ,Evaporation ,Analytical chemistry ,Nanoparticle ,DROPS ,Power law ,Contact angle ,QA273 ,NANOPARTICLES ,Electrochemistry ,General Materials Science ,WETTABILITY ,KINETICS ,Spectroscopy ,Range (particle radiation) ,Chemistry ,Surfaces and Interfaces ,ANGLE ,Condensed Matter Physics ,SOLID-SURFACES ,Volume (thermodynamics) ,Chemical physics ,SESSILE DROPLETS ,CONTACT LINE ,Wetting ,Constant (mathematics) - Abstract
The manner in which the extreme modes of droplet evaporation (namely, the constant contact radius and the constant contact angle modes) become indistinguishable on strongly hydrophobic substrates is described. Simple asymptotic expressions are obtained which provide good approximations to the evolutions of the contact radius, the contact angle, and the volume of droplets evaporating in the extreme modes for a wide range of hydrophobic substrates. As a consequence, on strongly hydrophobic substrates it is appropriate to use the so-called "2/3 power law" to extrapolate the lifetimes of droplets evaporating in the constant contact radius mode as well as in the constant contact angle mode.
- Published
- 2015
36. Improved anchorage in osteoporotic vertebrae with new implant designs
- Author
-
Christian Knop, Berend Linke, Jörg Goldhahn, M. Reinhold, R. Frei, M. Stauber, and Erich Schneider
- Subjects
Male ,musculoskeletal diseases ,medicine.medical_specialty ,Bone Screws ,Osteoporosis ,Lumbar vertebrae ,Lumbar ,Bone Density ,Humans ,Medicine ,Cyclic loading ,Orthopedics and Sports Medicine ,Aged ,Aged, 80 and over ,Bone mineral ,Orthodontics ,Lumbar Vertebrae ,business.industry ,Prostheses and Implants ,medicine.disease ,Biomechanical Phenomena ,Surgery ,medicine.anatomical_structure ,Female ,Stress, Mechanical ,Implant ,business ,Bone structure - Abstract
The goal of our study was to evaluate two newly developed implant designs and their behavior in terms of subsidence in lumbar vertebral bodies under cyclic loading. The new implants were evaluated in two different configurations (two small prototypes vs. one large prototype with similar load-bearing area) in comparison to a conventional screw-based implant (MACS TL). A pool of 13 spines with a total of 65 vertebrae was used to establish five testing groups of similar bone mineral density (BMD) distribution with eight lumbar vertebrae each. In additional to BMD assessment via dual-energy X-ray absorptiometry, cancellous BMD and structural parameters were determined using a new generation in vivo 3D-pQCT. The specimens were loaded sinusoidally in force control at 1 Hz for 1000 cycles at three load levels (100, 200, and 400 N). A survival analysis using the number of cycles until failure (Cox regression with covariates) was applied to reveal differences between implant groups. All new prototype configurations except the large cylinder survived significantly longer than the control group. The number of cycles until failure was significantly correlated with the structural parameter Tb.Sp. and similarly with the cancellous BMD for three of five implants. In both large prototypes the cycle number until failure significantly correlated with the preoperative distance to the upper endplates. Although the direct relationship between bone structure or density and mechanical breakage behavior cannot be conclusively proven, all the prototypes adapted for poor bone structure performed better than the comparable conventional implant. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
- Published
- 2006
37. Spinal neuronal activation during locomotor-like activity enabled by epidural stimulation and 5-hydroxytryptamine agonists in spinal rats
- Author
-
Paul O, Duru, Niranjala J K, Tillakaratne, Jung A, Kim, Hui, Zhong, Stacey M, Stauber, Trinh T, Pham, Mei S, Xiao, V Reggie, Edgerton, and Roland R, Roy
- Subjects
Epidural Space ,education ,Electric Stimulation Therapy ,Motor Activity ,Cholinergic Neurons ,Article ,Rats ,Serotonin Receptor Agonists ,Rats, Sprague-Dawley ,Spinal Cord ,Interneurons ,Animals ,Female ,Spinal Cord Injuries - Abstract
The neural networks that generate stepping in complete spinal adult rats remain poorly defined. To address this problem, we used c-fos (an activity-dependent marker) to identify active interneurons and motoneurons in the lumbar spinal cord of adult spinal rats during a 30-min bout of bipedal stepping. Spinal rats were either step trained (30 min/day, 3 days/week, for 7.5 weeks) or not step trained. Stepping was enabled by epidural stimulation and the administration of the serotonergic agonists quipazine and 8-OHDPAT. A third group of spinal rats served as untreated (no stimulation, drugs, or stepping) controls. The numbers of activated cholinergic central canal cluster cells and partition neurons were higher in both step-trained and nontrained rats than in untreated rats and were higher in nontrained than in step-trained rats. The latter finding suggests that daily treatment with epidural stimulation plus serotonergic agonist treatment without step training enhances the excitability of a broader cholinergic interneuronal population than does step training. The numbers of activated interneurons in laminae II-VI of lumbar cross-sections were higher in both step-trained and nontrained rats than in untreated rats, and they were highest in step-trained rats. This finding suggests that this population of interneurons is responsive to epidural stimulation plus serotonergic treatment and that load-bearing induced when stepping has an additive effect. The numbers of activated motoneurons of all size categories were higher in the step-trained group than in the other two groups, reflecting a strong effect of loading on motoneuron recruitment. In general, these results indicate that the spinal networks for locomotion are similar with and without brain input.We identified neurons within the spinal cord networks that are activated during assisted stepping in paraplegic rats. We stimulated the spinal cord and administered a drug to help the rats step. One group was trained to step and another was not trained. We observed a lower percentage of activated neurons in specific spinal cord regions in trained rats than in nontrained rats after a 1-hr stepping bout, suggesting that step training reduces activation of some types of spinal neurons. This observation indicates that training makes the spinal networks more efficient and suggests a "learning" phenomenon in the spinal cord without any brain input.
- Published
- 2014
38. Drogen und Arzneimittelabusus in der Frauenheilkunde
- Author
-
Ralph Kästner, M. Stauber, and Kristin Härtl
- Subjects
Gynecology ,03 medical and health sciences ,medicine.medical_specialty ,030219 obstetrics & reproductive medicine ,0302 clinical medicine ,business.industry ,030220 oncology & carcinogenesis ,medicine ,Obstetrics and Gynecology ,business - Abstract
Suchterkrankungen bei Frauen beinhalten in der gynakologischen Praxis eine Reihe von Implikationen. Die psychosomatische Sorgfaltspflicht erfordert v. a. im Bereich der Geburtshilfe, die Gesundheit des Ungeborenen mit zu beachten und somit den Muttern fruhzeitig seelische und korperliche Unterstutzung anzubieten. Die wesentlichen Elemente dieses Behandlungskonzepts werden dargestellt. Eingegangen wird auch auf die Komorbiditat der Patientinnen, den Umgang mit Drogennotfallen und die perioperative Substitution.
- Published
- 2004
39. Psychosomatische Aspekte des Mammakarzinoms
- Author
-
Kristin Härtl, M. Stauber, and Klaus Friese
- Subjects
Gynecology ,medicine.medical_specialty ,business.industry ,Obstetrics and Gynecology ,Medicine ,business - Abstract
In den letzten Jahrzehnten gewannen bei der Therapie von Patientinnen mit Mammakarzinom zunehmend psychosomatische Aspekte an Bedeutung. Der vorliegende Beitrag behandelt aktuelle Themen psychoonkologischer Forschung: psychosoziale Belastungen fur Patientinnen mit Mammakarzinom und ihre Angehorigen, Coping und Lebensqualitat. Psychotherapeutische Indikationen, mogliche Zielsetzungen und verschiedene psychotherapeutische Interventionen werden erlautert. Die Autoren skizzieren Forschungsfragen aktueller Studien ihrer Arbeitsgruppe an der I. Universitatsfrauenklinik Munchen.
- Published
- 2003
40. Gesundheitsbezogene Lebensqualität, Körpererleben und Angst bei Brustkrebspatientinnen im Langzeitverlauf
- Author
-
Ralph Kästner, Wolfgang Janni, Kristin Härtl, M. Stauber, and Harald Sommer
- Subjects
Gynecology ,medicine.medical_specialty ,business.industry ,Obstetrics ,medicine.medical_treatment ,Mammary gland ,Obstetrics and Gynecology ,medicine.disease ,medicine.anatomical_structure ,Breast cancer ,Quality of life ,Maternity and Midwifery ,medicine ,Anxiety ,Primary treatment ,medicine.symptom ,Surgical treatment ,business ,Mastectomy ,Psychopathology - Abstract
Purpose: Research on long-term quality of life after breast cancer has produced conflicting results. We investigated the impact of age, recurrence, and type of primary surgery on different aspects of long-term quality of life in women treated for breast cancer. Methods: A total of 306 women completed the QLQ-C30 (Version 2.0) questionnaire an average of 4.2 years after primary treatment for stage I - III breast cancer. Supplementary scales included body image, satisfaction with surgical treatment, and fear of recurrence. Results: The women had minor impairment of quality of life (67.0) and body image (25.9), a high degree of satisfaction with surgical treatment (6.8), and considerable fear of recurrence (61.4). There was no correlation between age and quality of life. Women with recurrence did not differ from those without recurrence in the symptom scales of the questionnaire. Women with recurrence reported lower quality of life (P < 0.01), less satisfaction with surgical treatment (P
- Published
- 2003
41. Substitutionsbehandlung von opiatabhängigen Schwangeren - Analyse der Behandlungverläufe an der 1. UFK München
- Author
-
A. Lieber, T. Grubert, A. Knobbe, B. C. Hahlweg, M. Stauber, Kristin Härtl, and Ralph Kästner
- Subjects
business.industry ,Maternity and Midwifery ,Obstetrics and Gynecology ,Medicine ,business - Published
- 2002
42. Role of axial base coordination in isonitrile binding and chalcogen atom transfer to vanadium(III) complexes
- Author
-
Elena V. Rybak-Akimova, Carl D. Hoff, Julia M. Stauber, Taryn D. Palluccio, Christopher C. Cummins, Subhojit Majumdar, Manuel Temprado, Burjor Captain, Xiaochen Cai, and Alexandra Velian
- Subjects
Models, Molecular ,Binding Sites ,Molecular Structure ,Kinetics ,Enthalpy ,Inorganic chemistry ,Vanadium ,chemistry.chemical_element ,Calorimetry ,Toluene ,Inorganic Chemistry ,Reaction rate ,Crystallography ,chemistry.chemical_compound ,Chalcogen ,Reaction rate constant ,chemistry ,Coordination Complexes ,Nitriles ,Chalcogens ,Quantum Theory ,Thermodynamics ,Physical and Theoretical Chemistry - Abstract
The enthalpy of oxygen atom transfer (OAT) to V[(Me3SiNCH2CH2)3N], 1, forming OV[(Me3SiNCH2CH2)3N], 1-O, and the enthalpies of sulfur atom transfer (SAT) to 1 and V(N[t-Bu]Ar)3, 2 (Ar = 3,5-C6H3Me2), forming the corresponding sulfides SV[(Me3SiNCH2CH2)3N], 1-S, and SV(N[t-Bu]Ar)3, 2-S, have been measured by solution calorimetry in toluene solution using dbabhNO (dbabhNO = 7-nitroso-2,3:5,6-dibenzo-7-azabicyclo[2.2.1]hepta-2,5-diene) and Ph3SbS as chalcogen atom transfer reagents. The V-O BDE in 1-O is 6.3 ± 3.2 kcal·mol(-1) lower than the previously reported value for 2-O and the V-S BDE in 1-S is 3.3 ± 3.1 kcal·mol(-1) lower than that in 2-S. These differences are attributed primarily to a weakening of the V-Naxial bond present in complexes of 1 upon oxidation. The rate of reaction of 1 with dbabhNO has been studied by low temperature stopped-flow kinetics. Rate constants for OAT are over 20 times greater than those reported for 2. Adamantyl isonitrile (AdNC) binds rapidly and quantitatively to both 1 and 2 forming high spin adducts of V(III). The enthalpies of ligand addition to 1 and 2 in toluene solution are -19.9 ± 0.6 and -17.1 ± 0.7 kcal·mol(-1), respectively. The more exothermic ligand addition to 1 as compared to 2 is opposite to what was observed for OAT and SAT. This is attributed to less weakening of the V-Naxial bond in ligand binding as opposed to chalcogen atom transfer and is in keeping with structural data and computations. The structures of 1, 1-O, 1-S, 1-CNAd, and 2-CNAd have been determined by X-ray crystallography and are reported.
- Published
- 2014
43. Genome-wide microarray-based screen for FOXJ1-dependent ciliary factors in the murine lung
- Author
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M Weidemann, Mark P. Kühnel, Manuela Kellner, O Dittrich-Breiholz, M Mai, K Lobschat, Karin Schuster-Gossler, A Gossler, and M Stauber
- Subjects
Pulmonary and Respiratory Medicine ,Murine lung ,Microarray ,Computational biology ,Biology ,Genome - Published
- 2014
44. On the lifetimes of evaporating droplets
- Author
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Khellil Sefiane, Brian R. Duffy, Stephen Wilson, and Jutta M. Stauber
- Subjects
Materials science ,phase change ,DROPS ,Substrate (electronics) ,Contact angle ,Physics::Fluid Dynamics ,Phase change ,Solid substrate ,SUBSTRATE ,Contact radius ,QA273 ,NANOPARTICLES ,HYSTERESIS ,KINETICS ,condensation/evaporation ,Mechanical Engineering ,Condensed Matter Physics ,Hysteresis ,Hydrophobic surfaces ,Mechanics of Materials ,SESSILE DROPLETS ,HYDROPHOBIC SURFACES ,TJ ,Atomic physics ,Constant (mathematics) ,SUPERHYDROPHOBIC SURFACE - Abstract
The complete description of the lifetime of a droplet on a solid substrate evaporating in a ‘stick–slide’ mode is obtained. The unexpectedly subtle relationship between the lifetime of such a droplet and the lifetimes of initially identical droplets evaporating in the extreme modes (namely the constant contact radius and constant contact angle modes) is described and summarised in an appropriate master diagram. In particular, it is shown that the lifetime of a droplet is not, in general, constrained by the lifetimes of the extreme modes.
- Published
- 2014
45. The stannylphosphide anion reagent sodium bis(triphenylstannyl) phosphide: synthesis, structural characterization, and reactions with indium, tin, and gold electrophiles
- Author
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Tabitha J. Miller, Markus W. Reintinger, Gang Wu, Abouzar Toubaei, Isabelle Tannou, Chao Huang, Alexandra Velian, Julia M. Stauber, Christopher C. Cummins, and Daniel Tofan
- Subjects
Phosphide ,Inorganic chemistry ,chemistry.chemical_element ,Crystal structure ,Nuclear magnetic resonance spectroscopy ,Medicinal chemistry ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Electrophile ,Physical and Theoretical Chemistry ,Homoleptic ,Indium ,Phosphine ,Natural bond orbital - Abstract
Treatment of P4 with in situ generated [Na][SnPh3] leads to the formation of the sodium monophosphide [Na][P(SnPh3)2] and the Zintl salt [Na]3[P7]. The former was isolated in 46% yield as the crystalline salt [Na(benzo-15-crown-5)][P(SnPh3)2] and used to prepare the homoleptic phosphine P(SnPh3)3, isolated in 67% yield, as well as the indium derivative (XL)2InP(SnPh3)2 (XL = S(CH2)2NMe2), isolated in 84% yield, and the gold complex (Ph3P)AuP(SnPh3)2. The compounds [Na(benzo-15-crown-5)][P(SnPh3)2], P(SnPh3)3, (XL)2InP(SnPh3)2, and (Ph3P)AuP(SnPh3)2 were characterized using multinuclear NMR spectroscopy and X-ray crystallography. The bonding in (Ph3P)AuP(SnPh3)2 was dissected using natural bond orbital (NBO) methods, in response to the observation from the X-ray crystal structure that the dative P:→Au bond is slightly shorter than the shared electron-pair P-Au bond. The bonding in (XL)2InP(SnPh3)2 was also interrogated using (31)P and (13)C solid-state NMR and computational methods. Co-product [Na]3[P7] was isolated in 57% yield as the stannyl heptaphosphide P7(SnPh3)3, following salt metathesis with ClSnPh3. Additionally, we report that treatment of P4 with sodium naphthalenide in dimethoxyethane at 22 °C is a convenient and selective method for the independent synthesis of Zintl ion [Na]3[P7]. The latter was isolated as the silylated heptaphosphide P7(SiMe3)3, in 67% yield, or as the stannyl heptaphosphide P7(SnPh3)3 in 65% yield by salt metathesis with ClSiMe3 or ClSnPh3, respectively.
- Published
- 2014
46. Zwangssterilisationen und Zwangsabruptiones an der I. Universitätsfrauenklinik München zwischen 1933 und 1945 - Versuch einer späten Lebenshilfe
- Author
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C. Horban, G. Kindermann, Ralph Kästner, M. Stauber, and O. Dathe
- Subjects
medicine.medical_specialty ,Coping (psychology) ,business.industry ,Compulsory sterilization ,Obstetrics and Gynecology ,Nazism ,humanities ,Surgery ,Nationalism ,Law ,Maternity and Midwifery ,Eugenics ,Medicine ,Financial compensation ,business ,Social Darwinism ,Racial hygiene - Abstract
Background: Ideas of social Darwinism and eugenics and nationalism intertwined in Germany around 1905 and led to the concept of racial hygiene. This was put into practice by the Nazi regime. Under the Law for the Prevention of Congenitally Deformed Descendents, between 300,000 and 400,000 people were involuntarily sterilized between 1933 and 1945. Method: A total of 1345 enforced sterilizations, including 58 compulsory abortions, were performed at the First Department of Gynecology at the University of Munich. 33.2% of these women were sterilized because they were considered mentally deficient but in 27.9% the records contained no explicit indication. Results: Financial compensation for the victims has been possible since 1980 but has been complicated by the passage of time and social stigmatization. Conclusion: The First Department of Gynecology undertook an attempt to contact the involuntarily sterilized women to express a belated apology on behalf of the department, to provide support for applications for financial compensation, and to offer counselling for coping with the physical and emotional trauma of compulsory sterilization. The reaction of the women has been very positive.
- Published
- 2001
47. Couple conflicts and therapeutic interventions with gynecological patients
- Author
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K. Härtl, M. Stauber, and Ralph Kästner
- Subjects
Gynecology ,medicine.medical_specialty ,business.industry ,medicine ,Obstetrics and Gynecology ,business - Abstract
Partnerschaftskonflikte konnen bei verschiedenen gynakologischen Problemen auftreten: Ungewollte Kinderlosigkeit, Ubergang zur Elternschaft, Schwangerschafts- und Wochenbettdepression, sexuelle Probleme, chronische Schmerzsyndrome wie Unterbauchschmerzen und Vulvodynie, Krebserkrankung. Im Umgang mit Partnerschaftskonflikten werden verschiedene therapeutische Ansatze beschrieben: psychoanalytische Therapie, systemische Therapie, Verhaltenstherapie, klientenzentrierte Therapie. Psychoanalytische Konzepte konzentrieren sich auf das Paar als zwei Individuen mit ihren jeweiligen individuellen Lebensgeschichten, die im Zusammenwirken zu Beziehungskonflikten fuhren konnen. Die systemische Therapie hat primar das Aushandeln und die Veranderung von Beziehungs- und Kommunikationsregeln durch Reflexion, Erprobung und Experimentieren zum Ziel. Die verhaltenstherapeutische Paartherapie basiert auf Ubungen zur Steigerung der Reziprozitat, Kommunikations- und Konfliktlosungstraining sowie Problemlosetraining. In klientenzentrierten Ansatzen geht es hauptsachlich darum, durch wachsende Kongruenz mit sich selbst zunehmend Klarheit in der Beziehung zum anderen zu finden. Der Artikel zeigt auf, dass Partnerschaftskonflikte im Rahmen eines biopsychosozialen Storungsmodells in der Entstehung, Aufrechterhaltung oder als Folge der gynakologischen Symptomatik berucksichtigt und therapeutisch behandelt werden sollten.
- Published
- 2001
48. Patterns of Mammography Use among Hispanic, American Indian, and Non-Hispanic White Women in New Mexico, 1994-1997
- Author
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Frank D. Gilliland, William C. Hunt, Charles R. Key, Patricia M. Stauber, and Robert D. Rosenberg
- Subjects
Adult ,Gerontology ,medicine.medical_specialty ,Epidemiology ,New Mexico ,Population ,Psychological intervention ,Ethnic group ,Breast Neoplasms ,Breast cancer ,Humans ,Mass Screening ,Medicine ,Mammography ,Community Health Services ,education ,Mass screening ,Aged ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,Public health ,Hispanic or Latino ,Middle Aged ,medicine.disease ,Indians, North American ,Female ,business ,Demography - Abstract
For screening efforts to maximally reduce mortality in the general population, a large proportion of women need to utilize mammography routinely. To investigate utilization of mammography in a community setting, the authors used population-based data collected by the New Mexico Mammography Project for residents of the Albuquerque, New Mexico, metropolitan area for the period 1994-1997. The authors computed screening rates and the proportion of women who routinely use mammography. The utilization of mammography was low. Only 50% of the women aged 50-74 years were screened each year. Less than one third of women aged 40-49 years or 75 years and older were screened annually. The percentage of women who routinely used mammography on an annual or biennial basis was low in all age groups, especially among Hispanics and American Indians. Women aged 50-74 years had the highest percentage of routine annual mammography use, ranging from 30% in non-Hispanic Whites to 20% in Hispanics. Current utilization of mammography in community-based screening efforts is unlikely to achieve a potential 30% reduction in breast cancer mortality. Interventions are needed to increase the routine use of mammography.
- Published
- 2000
49. Biologic Characteristics of Interval and Screen-Detected Breast Cancers
- Author
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Nancy E. Joste, Frank D. Gilliland, Patricia M. Stauber, William C. Hunt, Robert D. Rosenberg, Gillian Redlich, and Charles R. Key
- Subjects
Adult ,Oncology ,Cancer Research ,medicine.medical_specialty ,Time Factors ,Population ,Apoptosis ,Breast Neoplasms ,Breast cancer ,Internal medicine ,medicine ,Humans ,Mass Screening ,Mammography ,Breast ,Risk factor ,education ,Mass screening ,Aged ,Gynecology ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,Cancer ,Odds ratio ,Middle Aged ,medicine.disease ,Immunohistochemistry ,Confidence interval ,Ki-67 Antigen ,Proto-Oncogene Proteins c-bcl-2 ,Data Interpretation, Statistical ,Female ,Tumor Suppressor Protein p53 ,business - Abstract
Background: Interval breast cancer is defined as a cancer that is detected within 12 months after a negative mammogram. The failure of mammography to detect breast cancer depends on testing procedures, radiologist interpretation, patient characteristics, and tumor properties. Although errors by radiologists explain some interval cancers, another explanation is that the tumor is rapidly growing and was too small to be detected on the last mammogram. To determine whether markers of tumor growth rate are associated with risk of an interval cancer, we conducted a population-based study with the use of data collected statewide by the New Mexico Mammography Project. Methods: Among women who received a mammographic examination from 1991 throughout 1993, we ascertained records of all patients with breast cancer diagnosed within 12 months of a negative screening mammographic examination (interval cancers) and corresponding tumor samples, when available. We selected an age-and ethnicity-matched comparison group of control patients with screen-detected breast cancers diagnosed during the same period. In tumor samples, p53, bcl-2, and Ki-67 were examined immunologically and the apoptotic index was assessed histologically. We used logistic regression to determine whether interval cancers were associated with selected demographic, radiologic, and biologic characteristics. Results: It is more likely that mammography did not detect tumors with a high proportion of proliferating cells (>20%) than tumors with a low proportion of proliferating cells (
- Published
- 2000
50. Advances in Psychosomatic Obstetrics and Gynecology : Proceedings. Sixth International Congress of Psychosomatic Obstetrics and Gynecology, Berlin, Reichstag, September 2 - 6, 1980
- Author
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H.-J. Prill, M. Stauber, P. G. Pechatschek, H.-J. Prill, M. Stauber, and P. G. Pechatschek
- Subjects
- Gynecology, Psychotherapy
- Abstract
The Sixth International Congress of Psychosomatic Obstetrics and Gynecology, which took place from 2 to 6 September 1980 in the congressional chambers of the former Reichstag building in Berlin, had as its theme'Women in a Changing Society.'Partic ular emphasis was placed on the fact that in illness, as well as in good health, women must be considered in a comprehensive psychosocial context. Observations from medi cal, psychological, sociological, and anthropological perspectives on the healthy and sick woman through the various stages of her life presented a wide spectrum of scien tific research. Sessions covering such fundamental topics as the problems of the young mother, women in the postgenerative phase, and the early mother-child relationship were enriched by many recent scientific contributions. Further subjects, ranging from the dialogue in the gynecologist's consulting room through the emotional situation of the gynecologist, body language in female sexuality, and sexual disorders experienced by gynecological patients to psychosomatics and cancer, were pursued in small workshops. Of particular psychoendocrinological interest were the contributions on obesity and the premenstrual syndrome. The results of this workshop and another on unwanted pregnancy have ap peared recently in separate monographs.
- Published
- 2012
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