1
|
Bultink CC, O’Brien TE, Vollmer R, Muthusubramanian N, Beekman MW, Rol MA, Fu X, Tarasinski B, Ostroukh V, Varbanov B, Bruno A, DiCarlo L. Protecting quantum entanglement from leakage and qubit errors via repetitive parity measurements. Sci Adv 2020; 6:eaay3050. [PMID: 32219159 PMCID: PMC7083610 DOI: 10.1126/sciadv.aay3050] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 12/26/2019] [Indexed: 06/10/2023]
Abstract
Protecting quantum information from errors is essential for large-scale quantum computation. Quantum error correction (QEC) encodes information in entangled states of many qubits and performs parity measurements to identify errors without destroying the encoded information. However, traditional QEC cannot handle leakage from the qubit computational space. Leakage affects leading experimental platforms, based on trapped ions and superconducting circuits, which use effective qubits within many-level physical systems. We investigate how two-transmon entangled states evolve under repeated parity measurements and demonstrate the use of hidden Markov models to detect leakage using only the record of parity measurement outcomes required for QEC. We show the stabilization of Bell states over up to 26 parity measurements by mitigating leakage using postselection and correcting qubit errors using Pauli-frame transformations. Our leakage identification method is computationally efficient and thus compatible with real-time leakage tracking and correction in larger quantum processors.
Collapse
Affiliation(s)
- C. C. Bultink
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - T. E. O’Brien
- Instituut-Lorentz for Theoretical Physics, Leiden University P.O. Box 9506, 2300 RA Leiden, Netherlands
| | - R. Vollmer
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - N. Muthusubramanian
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - M. W. Beekman
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Netherlands Organisation for Applied Scientific Research (TNO), P.O. Box 155, 2600 AD Delft, Netherlands
| | - M. A. Rol
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - X. Fu
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - B. Tarasinski
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - V. Ostroukh
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - B. Varbanov
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - A. Bruno
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| | - L. DiCarlo
- QuTech, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology P.O. Box 5046, 2600 GA Delft, Netherlands
| |
Collapse
|
2
|
Rol MA, Battistel F, Malinowski FK, Bultink CC, Tarasinski BM, Vollmer R, Haider N, Muthusubramanian N, Bruno A, Terhal BM, DiCarlo L. Fast, High-Fidelity Conditional-Phase Gate Exploiting Leakage Interference in Weakly Anharmonic Superconducting Qubits. Phys Rev Lett 2019; 123:120502. [PMID: 31633950 DOI: 10.1103/physrevlett.123.120502] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Indexed: 06/10/2023]
Abstract
Conditional-phase (cz) gates in transmons can be realized by flux pulsing computational states towards resonance with noncomputational ones. We present a 40 ns cz gate based on a bipolar flux pulse suppressing leakage (0.1%) by interference and approaching the speed limit set by exchange coupling. This pulse harnesses a built-in echo to enhance fidelity (99.1%) and is robust to long-timescale distortion in the flux-control line, ensuring repeatability. Numerical simulations matching experiment show that fidelity is limited by high-frequency dephasing and leakage by short-timescale distortion.
Collapse
Affiliation(s)
- M A Rol
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| | - F Battistel
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| | - F K Malinowski
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| | - C C Bultink
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| | - B M Tarasinski
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| | - R Vollmer
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| | - N Haider
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Netherlands Organisation for Applied Scientic Research (TNO), P.O. Box 96864, 2509 JG The Hague, The Netherlands
| | - N Muthusubramanian
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| | - A Bruno
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| | - B M Terhal
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- JARA Institute for Quantum Information, Forschungszentrum Juelich, D-52425 Juelich, Germany
| | - L DiCarlo
- QuTech, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
| |
Collapse
|
3
|
Dias-Santagata D, Selim MA, Su Y, Peng Y, Vollmer R, Chłopik A, Tell-Marti G, Paral KM, Shalin SC, Shea CR, Puig S, Fernandez-Figueras MT, Biernat W, Ryś J, Marszalek A, Hoang MP. KIT mutations and CD117 overexpression are markers of better progression-free survival in vulvar melanomas. Br J Dermatol 2017; 177:1376-1384. [PMID: 28734009 DOI: 10.1111/bjd.15836] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2017] [Indexed: 01/01/2023]
Abstract
BACKGROUND Few studies have addressed prognostic markers and none has correlated molecular status and prognosis in vulvar melanomas. OBJECTIVES To evaluate the clinicopathological features of 95 cases of vulvar melanoma. METHODS p53, CD117, Ki-67, neurofibromin, brafv600e and nrasq61r immunostains, and molecular analyses by either targeted next-generation or direct sequencing, were performed on available archival materials. RESULTS Molecular testing detected mutations in KIT (44%), BRAF (25%), NF1 (22%), TP53 (17%), NRAS (9%) and TERT promoter (9%). Co-mutation of KIT and NF1 and of KIT and NRAS were identified in two and one cases, respectively. KIT mutations were significantly associated with better progression-free survival in univariate analyses. In multivariate analyses CD117 expression was significantly associated with better progression-free survival. Tumour thickness was significantly associated with worse progression-free and overall survival, and perineural invasion significantly correlated with reduced melanoma-specific survival and reduced overall survival. Cases were from multiple centres and only a subset of samples was available for molecular testing. CONCLUSIONS KIT mutations and CD117 overexpression are markers of better progression-free survival. In addition to its prognostic value, molecular testing may identify cases that might respond to targeted agents or immunotherapeutic approaches.
Collapse
Affiliation(s)
- D Dias-Santagata
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, U.S.A
| | - M A Selim
- Duke University Medical Center, Durham, NC, U.S.A
| | - Y Su
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, U.S.A
| | - Y Peng
- University of Texas Southwestern Medical Center, Dallas, TX, U.S.A
| | - R Vollmer
- Duke University Medical Center, Durham, NC, U.S.A
| | - A Chłopik
- Poznan University Medical Sciences and Greater Poland Cancer Center, Poznan, Poland
| | - G Tell-Marti
- Department of Dermatology, Melanoma Unit, Hospital Clínic de Barcelona, IDIBAPS, and Centre of Biomedical Research on Rare Diseases (CIBERER), ISCIII, Barcelona, Spain
| | - K M Paral
- Duke University Medical Center, Durham, NC, U.S.A
| | - S C Shalin
- University of Arkansas for Medical Sciences, Little Rock, AR, U.S.A
| | - C R Shea
- Department of Medicine, Section of Dermatology, University of Chicago, IL, U.S.A
| | - S Puig
- Department of Dermatology, Melanoma Unit, Hospital Clínic de Barcelona, IDIBAPS, and Centre of Biomedical Research on Rare Diseases (CIBERER), ISCIII, Barcelona, Spain
| | - M T Fernandez-Figueras
- Hospital Universitari Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - W Biernat
- Medical University of Gdansk, Gdansk, Poland
| | - J Ryś
- Center of Oncology, M. Sklodowska-Curie Memorial Institute, Krakow, Poland
| | - A Marszalek
- Poznan University Medical Sciences and Greater Poland Cancer Center, Poznan, Poland
| | - M P Hoang
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, U.S.A
| |
Collapse
|
4
|
Loughran T, Schumacher J, Harpel T, Vollmer R. Effectiveness of Intuitive Eating Intervention through a Text Messaging Program among College Students. J Acad Nutr Diet 2017. [DOI: 10.1016/j.jand.2017.08.065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
5
|
Black H, Schumacher J, Harpel T, Vollmer R. Analysis of Pinterest as a Tool for Dissemination of Nutrition Information for Parents of Teenagers. J Acad Nutr Diet 2017. [DOI: 10.1016/j.jand.2017.08.084] [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: 10/18/2022]
|
6
|
Vollmer R, Villagaray R, Egusquiza V, Espirilla J, García M, Torres A, Rojas E, Panta A, Barkley NA, Ellis D. The Potato Cryobank at The International Potato Center (Cip): A Model for Long Term Conservation of Clonal Plant Genetic Resources Collections of the Future. Cryo Letters 2016; 37:318-329. [PMID: 27924999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
BACKGROUND Cryobanks are a secure, efficient and low cost method for the long-term conservation of plant genetic resources for theoretically centuries or millennia with minimal maintenance. OBJECTIVE The present manuscript describes CIP's modified protocol for potato cryopreservation, its large-scale application, and the establishment of quality and operational standards, which included a viability reassessment of material entering the cryobank. MATERIALS AND METHODS In 2013, CIP established stricter quality and operational standards under which 1,028 potato accessions were cryopreserved with an improved PVS2-droplet protocol. In 2014 the viability of 114 accessions cryopreserved in 2013 accessions were reassessed. RESULTS The average recovery rate (full plant recovery after LN exposure) of 1028 cryopreserved Solanum species ranged from 34 to 59%, and 70% of the processed accessions showed a minimum recovery rate of ≥20% and were considered as successfully cryopreserved. CONCLUSION CIP has established a new high quality management system for cryobanking. Periodic viability reassessment, strict and clear recovery criteria and the monitoring of the percent of successful accessions meeting the criteria as well as contamination rates are metrics that need to be considered in cryobanks.
Collapse
Affiliation(s)
- R Vollmer
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru.
| | - R Villagaray
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| | - V Egusquiza
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| | - J Espirilla
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| | - M García
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| | - A Torres
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| | - E Rojas
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| | - A Panta
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| | - N A Barkley
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| | - D Ellis
- International Potato Center, Av. La Molina 1895, La Molina, Lima, Peru
| |
Collapse
|
7
|
Szirmai I, Vollmer R, Lapins R. Analysis of cortical spread of acetylcholine (ACh)--induced epileptiform discharges. Monogr Neural Sci 2015; 5:25-9. [PMID: 7322161 DOI: 10.1159/000387479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|
8
|
Turner J, Vollmer R. Impact of the Poisson Distribution on Lymph Node Staging of Malignant Melanoma. J Cutan Pathol 2008. [DOI: 10.1111/j.0303-6987.2005.320hi.x] [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: 11/27/2022]
|
9
|
|
10
|
D'Amico A, Halabi S, Vollmer R, Loffredo M, McMahon E, Sanford B, Archer L, Vogelzang N, Small E, Kantoff P. p53 Protein Expression Status and Recurrence in Men Treated With Radiation Therapy and Androgen Suppression Therapy for Higher Risk Prostate Cancer: A Prospective Phase II Cancer and Leukemia Group B Study. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
11
|
D’Amico AV, Halabi S, Tempany C, Vollmer R, Loffredo M, Sanford B, Small EJ. Changes on endorectal MRI during neoadjuvant hormonal therapy for prostate cancer and biochemical outcome in men managed using radiation therapy: A prospective phase II Cancer and Leukemia Group B study. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.5072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
5072 Background: We prospectively determined whether changes in tumor volume (TV) on 1.5 Tesla endorectal magnetic resonance imaging (eMRI) during neoadjuvant androgen suppression therapy (AST) were associated with biochemical outcome after radiation and 6 months of AST. Methods: Between May, 1996 and April, 2001,180 men with T1c-T3c non-metastatic adenocarcinoma of the prostate cancer were registered. Fifteen were found to be ineligible leaving 165 men who had a eMRI TV measurement at baseline and following 2 months of neoadjuvant AST. An eMRI response was defined as > 10% reduction in the volume of all lesions consistent with prostate cancer. In 32 men, the institutional MR radiologist could not completely assess the TV leaving 133 for analysis. A proportional hazards model was used to assess whether a significant association existed between eMRI response and time to prostate-specific antigen (PSA) failure following registration adjusting for PSA level (continuous), Gleason score (8 to 10 or 7 versus 6 or less) and stage (T3 versus T1, 2). PSA failure was defined as 2 consecutive rises of 0.2 above 1.0 ng/ml (PSA fail) and according to the 1997 and the 2006 American Society of Therapeutic Radiology and Oncology (ASTRO) consensus definitions. Results: The median age and PSA level of the study cohort were 70 years and 10.7 ng/ml respectively. An eMRI response was noted in 112 (84%) men and 85, 47, and 47 men experienced PSA failure based on the 1997, 2006 ASTRO consensus and PSA fail definitions respectively. After a median follow up of 6.7 years and adjusting for known prognostic factors, there was a statistically significant association between eMRI defined tumor response and time to PSA failure using the 1997 (p = 0.04) and 2006 (p = 0.009) ASTRO consensus definitions and a near significant association (p = 0.08) using PSA fail. Conclusion: Men lacking a > 10% reduction in the eMRI defined TV during neoadjuvant AST are at increased risk for recurrence following radiation and AST. Therefore, eMRI enables the early documentation of androgen insensitive disease and identifies men for trials evaluating outcome when non-AST based approaches are combined with radiation and AST. No significant financial relationships to disclose.
Collapse
Affiliation(s)
- A. V. D’Amico
- Brigham and Women’s Hospital, Boston, MA; Duke University, Durham, NC; University of California San Francisco, San Francisco, CA
| | - S. Halabi
- Brigham and Women’s Hospital, Boston, MA; Duke University, Durham, NC; University of California San Francisco, San Francisco, CA
| | - C. Tempany
- Brigham and Women’s Hospital, Boston, MA; Duke University, Durham, NC; University of California San Francisco, San Francisco, CA
| | - R. Vollmer
- Brigham and Women’s Hospital, Boston, MA; Duke University, Durham, NC; University of California San Francisco, San Francisco, CA
| | - M. Loffredo
- Brigham and Women’s Hospital, Boston, MA; Duke University, Durham, NC; University of California San Francisco, San Francisco, CA
| | - B. Sanford
- Brigham and Women’s Hospital, Boston, MA; Duke University, Durham, NC; University of California San Francisco, San Francisco, CA
| | - E. J. Small
- Brigham and Women’s Hospital, Boston, MA; Duke University, Durham, NC; University of California San Francisco, San Francisco, CA
| |
Collapse
|
12
|
Abstract
We have reported that a rapid tail vein injection of a large volume of plasmid DNA solution into a mouse results in high level of transgene expression in the liver. Gene transfer efficiency of this hydrodynamics-based procedure is determined by the combined effect of a large volume and high injection speed. Here, we show that the hydrodynamic injection induces a transient irregularity of heart function, a sharp increase in venous pressure, an enlargement of liver fenestrae, and enhancement of membrane permeability of the hepatocytes. At the cellular level, our results suggest that hepatic delivery by the hydrodynamic injection is accomplished by the generation of membrane pores in the hepatocytes.
Collapse
Affiliation(s)
- G Zhang
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, PA 15261, USA
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Vollmer R, Etzkorn M, Kumar PSA, Ibach H, Kirschner J. Spin-polarized electron energy loss spectroscopy of high energy, large wave vector spin waves in ultrathin fcc Co films on Cu(001). Phys Rev Lett 2003; 91:147201. [PMID: 14611549 DOI: 10.1103/physrevlett.91.147201] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2003] [Indexed: 05/23/2023]
Abstract
The realm of high energy, large wave vector spin waves in ultrathin films and at surfaces is unexplored because a suitable method was not available up to now. We present experimental data for an 8 ML thick Co film deposited on Cu(001) which show that spin-polarized electron energy loss spectroscopy can be used to measure spin-wave dispersion curves of ultrathin ferromagnetic films up to the surface Brillouin zone boundary.
Collapse
Affiliation(s)
- R Vollmer
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany.
| | | | | | | | | |
Collapse
|
14
|
|
15
|
Vollmer R, Faisst A, Pfleiderer C, V Löhneysen H, Bauer ED, Ho PC, Zapf V, Maple MB. Low-temperature specific heat of the heavy-fermion superconductor PrOs4Sb12. Phys Rev Lett 2003; 90:057001. [PMID: 12633389 DOI: 10.1103/physrevlett.90.057001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2002] [Indexed: 05/24/2023]
Abstract
We report the magnetic field dependence of the specific-heat C of single crystals of the first Pr-based heavy-fermion superconductor Pr(Os4Sb12. The variation of C at low temperature and the magnetic phase diagram inferred from C, the resistivity and magnetization provide compelling evidence of a doublet ground state. Two distinct superconducting anomalies in C indicate an unconventional superconducting state, where the splitting may arise from a weak lifting of the ground state degeneracy. In combination this identifies Pr(Os4Sb12 as a strong contender for quadrupolar pairing, i.e., superconductivity that is neither electron-phonon nor magnetically mediated.
Collapse
Affiliation(s)
- R Vollmer
- Physikalisches Institut, Universität Karlsruhe, Wolfgang-Gaede-Strasse 1, Germany
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Griehl C, Junghannß U, Bieler S, Vollmer R. Mikrobiologische und analytische Untersuchungen zur Vergärbarkeit proteinreicher Substrate. CHEM-ING-TECH 2002. [DOI: 10.1002/1522-2640(200205)74:5<695::aid-cite1111695>3.0.co;2-4] [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: 11/08/2022]
|
17
|
Pfleiderer C, Uhlarz M, Hayden SM, Vollmer R, v Löhneysen H, Bernhoeft NR, Lonzarich GG. Coexistence of superconductivity and ferromagnetism in the d-band metal ZrZn2. Nature 2001; 412:58-61. [PMID: 11452303 DOI: 10.1038/35083531] [Citation(s) in RCA: 386] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It has generally been believed that, within the context of the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity, the conduction electrons in a metal cannot be both ferromagnetically ordered and superconducting. Even when the superconductivity has been interpreted as arising from magnetic mediation of the paired electrons, it was thought that the superconducting state occurs in the paramagnetic phase. Here we report the observation of superconductivity in the ferromagnetically ordered phase of the d-electron compound ZrZn2. The specific heat anomaly associated with the superconducting transition in this material appears to be absent, and the superconducting state is very sensitive to defects, occurring only in very pure samples. Under hydrostatic pressure superconductivity and ferromagnetism disappear at the same pressure, so the ferromagnetic state appears to be a prerequisite for superconductivity. When combined with the recent observation of superconductivity in UGe2 (ref. 4), our results suggest that metallic ferromagnets may universally become superconducting when the magnetization is small.
Collapse
Affiliation(s)
- C Pfleiderer
- Physikalisches Institut, Universität Karlsruhe, D-76128 Karlsruhe, Germany
| | | | | | | | | | | | | |
Collapse
|
18
|
Ferguson TJ, Stegge H, Eyre HL, Vollmer R, Ashbaker M. Context effects and the (mal)adaptive nature of guilt and shame in children. Genet Soc Gen Psychol Monogr 2000; 126:319-45. [PMID: 10950200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Symptoms of internalization were examined in relation to children's self-reports of three emotions in situations that were either ambiguous or unambiguous as to the child's responsibility for various standard violations. Children ranging in age from 6 to 13 years were drawn from elementary schools (61 boys, 79 girls, mean age = 8.7) and from a community mental health center (23 boys, 18 girls, mean age = 8.5) to which they had been referred for problems related to internalization or externalization. Shame proneness was consistently linked to internalizing symptoms across contexts. Guilt proneness, in response to ambiguous scenarios, was also associated with internalization, whereas pride responses were unrelated to symptoms. Few age- or gender-related differences were found. The results cast doubt on notions that self-conscious emotions, such as guilt, are necessarily adaptive or maladaptive. Systematic research is needed to understand which features of any emotion contribute to children's psychological adjustment.
Collapse
Affiliation(s)
- T J Ferguson
- Department of Psychology, Utah State University, Logan 84322-2810, USA.
| | | | | | | | | |
Collapse
|
19
|
Persons DA, Garst J, Vollmer R, Crawford J. Tumor lysis syndrome and acute renal failure after treatment of non-small-cell lung carcinoma with combination irinotecan and cisplatin. Am J Clin Oncol 1998; 21:426-9. [PMID: 9708649 DOI: 10.1097/00000421-199808000-00024] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Tumor lysis syndrome, characterized by multiple metabolic abnormalities resulting from abrupt tumor cell death and release of intracellular constituents and metabolites, is most commonly associated with the treatment of highly chemotherapy-sensitive lymphoid and leukemic neoplasms. The authors report a case of tumor lysis syndrome accompanied by acute renal failure that occurred in a patient with stage IV non-small-cell lung cancer who was treated with topoisomerase I inhibitor, irinotecan, and cisplatin. Consistent with the rapid tumor lysis, an objective, marked, early clinical response was observed. Attention to adequate hydration, electrolytes, and renal function should be given to outpatients with non-small-cell lung cancer who receive newer chemotherapeutic agents that have greater efficacy toward this group of tumors.
Collapse
Affiliation(s)
- D A Persons
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA
| | | | | | | |
Collapse
|
20
|
Straub M, Vollmer R, Kirschner J. Surface Magnetism of Ultrathin gamma -Fe Films Investigated by Nonlinear Magneto-optical Kerr Effect. Phys Rev Lett 1996; 77:743-746. [PMID: 10062891 DOI: 10.1103/physrevlett.77.743] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
21
|
Lange G, Schmicker D, Toennies JP, Vollmer R, Weiss H. The structure and dynamics of CO2 on NaCl(001) studied by helium atom scattering. J Chem Phys 1995. [DOI: 10.1063/1.469706] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
|
22
|
Wierenga HA, Prins MW, Rasing T, Vollmer R, Kirilyuk A, Schwabe H, Kirschner J. Interface magnetism and possible quantum well oscillations in ultrathin Co/Cu films observed by magnetization induced second harmonic generation. Phys Rev Lett 1995; 74:1462-1465. [PMID: 10059026 DOI: 10.1103/physrevlett.74.1462] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
23
|
Höche H, Toennies JP, Vollmer R. Combined electron-microscope surface-decoration and helium-atom-scattering study of the layer-by-layer photon-stimulated desorption from NaCl cleavage faces. Phys Rev B Condens Matter 1994; 50:679-691. [PMID: 9975729 DOI: 10.1103/physrevb.50.679] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
24
|
Merlo A, Gabrielson E, Mabry M, Vollmer R, Baylin SB, Sidransky D. Homozygous deletion on chromosome 9p and loss of heterozygosity on 9q, 6p, and 6q in primary human small cell lung cancer. Cancer Res 1994; 54:2322-6. [PMID: 8162574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We analyzed the pattern of allelic loss in 33 primary human small cell lung cancers (SCLCs) using highly informative microsatellite markers on chromosomes 2p, 3p, 5q, 6, 9, 13q, and 17p. Nineteen of these tumors (58%) displayed loss of heterozygosity on chromosome 9. Fourteen SCLCs demonstrated loss of heterozygosity for all informative markers on both chromosomal arms; two tumors demonstrated partial loss on chromosome 9p. In one tumor, a multiplex polymerase chain reaction assay disclosed a homozygous deletion at 9p21-22 including the markers IFN-alpha, D9S126, and D9S171. Two SCLCs retained all informative markers on 9p but showed allelic loss of the entire 9q arm, while one case had a partial loss of proximal 9q extending into all of 9p. Analysis of other chromosomal arms showed loss of heterozygosity on 3p (93%), 5q (75%), 6p (46%), 6q (47%), 13q (75%), and 17p (93%). It was necessary to test multiple markers at several loci because of the frequent expression of microsatellite instability that confounded our mapping efforts in SCLCs with replication errors. This study demonstrates the frequent loss of a suppressor gene locus on chromosome 9p21-22 and identifies novel suppressor loci on 6p, 6q, and 9q in primary SCLC.
Collapse
Affiliation(s)
- A Merlo
- Department of Otolaryngology, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205
| | | | | | | | | | | |
Collapse
|
25
|
Merlo A, Mabry M, Gabrielson E, Vollmer R, Baylin SB, Sidransky D. Frequent microsatellite instability in primary small cell lung cancer. Cancer Res 1994; 54:2098-101. [PMID: 8174113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Alterations in microsatellite sequences characterize hereditary nonpolyposis colorectal cancer. This microsatellite instability is due in some kindreds to a germline mutation of the mismatch repair gene hMSH2 on chromosome 2p. Although microsatellite alterations have been reported in other hereditary nonpolyposis colorectal cancer-associated tumors including endometrial and gastric cancers, such changes were not detected in most other major neoplasms. We found that 15 of 33 (45%) primary small cell lung cancers, tumors not found in the hereditary nonpolyposis colorectal cancer syndrome, displayed alterations of microsatellite loci which consisted of deletions or expansions of (CA)n dinucleotide repeats. In 8 of these 15 neoplasms, microsatellite instability was detected in more than 10% of all tested alleles. However, small cell lung cancers that revealed instability contained widespread allelic loss and had a uniformly poor prognosis. These results expand considerably the known spectrum of tumors with microsatellite instability.
Collapse
Affiliation(s)
- A Merlo
- Department of Otolaryngology, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205
| | | | | | | | | | | |
Collapse
|
26
|
Höche H, Toennies JP, Vollmer R. Photon-stimulated layer-by-layer desorption from NaCl(001) surfaces monitored by helium-atom scattering. Phys Rev Lett 1993; 71:1208-1211. [PMID: 10055477 DOI: 10.1103/physrevlett.71.1208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
27
|
|
28
|
Schmicker D, Toennies JP, Vollmer R, Weiss H. Monolayer structures of carbon monoxide adsorbed on sodium chloride: A helium atom diffraction study. J Chem Phys 1991. [DOI: 10.1063/1.461171] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
29
|
Schmicker D, Schmidt S, Skofronick JG, Toennies JP, Vollmer R. Epitaxial growth of single-crystal C60 on mica by helium-atom scattering. Phys Rev B Condens Matter 1991; 44:10995-10997. [PMID: 9999145 DOI: 10.1103/physrevb.44.10995] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
30
|
Toennies JP, Vollmer R. He-atom-scattering studies of the structure and dynamics of the KMnF3(001) surface and the 186-K phase transition. Phys Rev B Condens Matter 1991; 44:9833-9852. [PMID: 9998985 DOI: 10.1103/physrevb.44.9833] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
31
|
Abstract
One hundred eight-five patients with acral melanoma treated since 1972 were reviewed. These included 53 subungual lesions, 123 plantar lesions, and 9 palmar lesions. Eighty percent presented with stage I disease. Mean age was 57 years. Males outnumbered females 1.1:1. Seventeen percent (17%) were blacks. Actuarial 10-year survival was 58% for stage I patients and 35% for stage II patients. Univariate Cox regression analyses identified 5 prognostic variables affecting survival: stage at diagnosis (P less than 0.001), race (P less than 0.001), ulceration (P = 0.012), Clark's level (P = 0.014), and thickness of the primary lesion (P = 0.013). Factors unrelated to survival included sex of the patient, site (volar vs. subungual), histology, and treatment with amputation. Multivariate analysis for patients with stage I lesions identified race (P = 0.001) and ulceration (P = 0.018) as significant variables, with thickness approaching significance (P = 0.094). In an additional series of 71 patients with melanomas arising from extremity sites near the junction of glabrous and non-glabrous skin, survival was significantly poorer for those arising from glabrous skin (P = 0.024), and reflects a higher incidence of metastatic disease at diagnosis. Specific active immunotherapy was the principal adjuvant used for these patients, and survival was comparable to that reported with regional perfusion therapy. Acral melanoma a) has a strong racial predilection, b) carries a grave prognosis, and c) arises from glabrous skin. It is a clinical entity distinct from other extremity melanomas. Surgical management with either wide excision or amputation is appropriate for the primary lesion.
Collapse
Affiliation(s)
- C L Slingluff
- Department of Surgery, Duke University Medical Center, Durham, N.C. 27710
| | | | | |
Collapse
|
32
|
Skinner MA, Vollmer R, Huper G, Abbott P, Iglehart JD. Loss of heterozygosity for genes on 11p and the clinical course of patients with lung carcinoma. Cancer Res 1990; 50:2303-6. [PMID: 2180565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Forty-five primary human lung carcinomas were evaluated for the loss of heterozygosity for genes on the short end of chromosome 11. Of 40 evaluable heterozygous cases, loss of the 11p genes c-H-ras and insulin was documented in nine cases (22%). The clinical parameters investigated for each patient included the disease stage at presentation, the presence of metastatic disease in either bronchial or mediastinal lymph nodes, and the presence of positive parietal pleural margins in the surgically resected specimen. There were no differences found with respect to these indicators when patients exhibiting the loss of heterozygosity were compared with those who did not have such genetic loss. In addition, when the clinical courses of the two patient groups were compared, there was no difference in survival. We conclude that the loss of heterozygosity for c-H-ras and insulin on 11p is a common finding in primary non-small cell human lung carcinomas but does not confer a more aggressive phenotype on these tumors. Although this genetic lesion may be important in the initial transformation of the cells to carcinoma, the available data for lung carcinoma are insufficient to prove causality.
Collapse
Affiliation(s)
- M A Skinner
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710
| | | | | | | | | |
Collapse
|
33
|
Brusdeylins G, Heimlich C, Skofronick JG, Toennies JP, Vollmer R, Benedek G, Miglio L. He-atom scattering study of the temperature-dependent charge-density-wave surface structure and lattice dynamics of 2H-TaSe2(001). Phys Rev B Condens Matter 1990; 41:5707-5716. [PMID: 9994454 DOI: 10.1103/physrevb.41.5707] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
34
|
Toennies JP, Vollmer R. Helium scattering studies of the dynamics of a xenon-monolayer-covered graphite single-crystal surface. Phys Rev B Condens Matter 1989; 40:3495-3498. [PMID: 9992318 DOI: 10.1103/physrevb.40.3495] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
35
|
Slingluff CL, Vollmer R, Seigler HF. Stage II malignant melanoma: presentation of a prognostic model and an assessment of specific active immunotherapy in 1,273 patients. J Surg Oncol 1988; 39:139-47. [PMID: 3184950 DOI: 10.1002/jso.2930390302] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [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: 01/04/2023]
Abstract
The ability to redefine risk factors and to predict prognosis in patients with malignant melanoma at the time they manifest nodal metastasis can be a benefit to the patient emotionally and to the physician therapeutically. A retrospective review of 1,273 patients with stage II malignant melanoma was performed at our institution. The most significant prognostic factors in a simultaneous hazard Cox multivariate analysis, predicting melanoma-related mortality among stage II patients, were the number of positive nodes (P less than 0.0001), age (P = 0.0004), site of the primary lesion (P = 0.0036), disease-free interval (P = 0.016), thickness of the primary lesion (P = 0.017), and sex of the patient (P = 0.0616). We have developed a model for predicting survival of stage II patients, designed for use in the clinic setting. Its application in a computer system makes it accessible and understandable. The most favorable risk group (18% of the population) has actuarial 5- and 10-year survival rates of 58% and 49%, respectively, from the time of the nodal metastasis. The least favorable risk group (7% of the population) has 5- and 10-year survival rates of 15% and 10%, respectively. There are three intermediate risk groups. All groups differ prognostically (P less than 0.04). The principal adjuvant therapy offered to these patients was specific active immunotherapy, which appears to have a 10-20% survival benefit in stage II patients with greater than one positive node, when compared with institutional controls. The apparent survival benefit of the immunotherapy supports continued clinical investigation of its therapeutic potential.
Collapse
Affiliation(s)
- C L Slingluff
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710
| | | | | |
Collapse
|
36
|
Benedek G, Brusdeylins G, Heimlich C, Miglio L, Skofronick JG, Toennies JP, Vollmer R. Shifted surface-phonon anomaly in 2H-TaSe2. Phys Rev Lett 1988; 60:1037-1040. [PMID: 10037925 DOI: 10.1103/physrevlett.60.1037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
37
|
Johnson DH, Einhorn LH, Birch R, Vollmer R, Perez C, Krauss S, Omura G, Greco FA. A randomized comparison of high-dose versus conventional-dose cyclophosphamide, doxorubicin, and vincristine for extensive-stage small-cell lung cancer: a phase III trial of the Southeastern Cancer Study Group. J Clin Oncol 1987; 5:1731-8. [PMID: 2824707 DOI: 10.1200/jco.1987.5.11.1731] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.5] [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: 01/02/2023] Open
Abstract
To assess the effect of dose escalation in the treatment of small-cell lung cancer (SCLC), 298 patients with extensive-stage disease were treated with either conventional-dose cyclophosphamide (1,000 mg/m2), doxorubicin (40 mg/m2), and vincristine (1 mg/m2), (CDCAV); or high-dose cyclophosphamide (1,200 mg/m2), doxorubicin (70 mg/m2), and vincristine (1 mg/m2) (HDCAV). No dose attenuation was allowed during the initial three cycles of therapy in either treatment arm. All patients received CDCAV in cycles 4 through 6, during which time dosages were adjusted according to granulocyte and platelet nadirs. No additional chemotherapy was administered until disease progression or relapse was documented. Complete responses were more frequent with HDCAV (22% v 12%; P = .045). However, overall response rate (63% v 53%) and median survival (29.3 v 34.7 weeks) were not significantly different (P greater than .05). HDCAV was substantially more toxic than CDCAV, causing more episodes of life-threatening leukopenia (ie, granulocytes less than 500/microL; 79% v 40%; P less than .05) and infections (15% v 4%; P less than .05). Dose intensification of cyclophosphamide and doxorubicin during induction chemotherapy did not produce any survival benefit compared with conventional dosages of these agents in SCLC patients with extensive-stage disease.
Collapse
|
38
|
Abstract
The outcome of patients with stage I malignant melanoma has been well assessed in terms of prognostic factors and their effect on survival; however, little is known of the recurrence patterns of cutaneous melanoma or the survival of these patients subsequent to recurrence. A retrospective, computer-aided chart review identified 4185 patients with melanoma who had stage I disease clinically. During a follow-up period of one to 14 years, 35.9% suffered a recurrence. Melanoma of the trunk (37.8%) and head and neck area (46.1%) had an increased incidence of recurrent metastases compared with melanoma of the extremities (29.8%). Local regional metastases accounted for 62.5%, 77.3%, and 85.6% of the recurrences in the head and neck, trunk, and extremity primary sites, respectively, with 65% of the relapses occurring within the first three years. Actuarial five-year survival rates of patients who had recurrent disease were significantly decreased compared with those of patients who had no evidence of metastases during their clinical course. A multivariate analysis was performed to estimate the survival of patients after recurrence. One may use this mathematical model to predict the outcome of individual patients after recurrence and provide a more rationally based prognosis for them and their families.
Collapse
Affiliation(s)
- D S Reintgen
- Department of Surgery, Duke University Medical Center, Durham, NC 27710
| | | | | | | |
Collapse
|
39
|
Reschenhofer E, Vollmer R, Deistler M. Segmentation of the EEG by minimization of the total gain in information. Neuropsychobiology 1987; 18:155-9. [PMID: 3453432 DOI: 10.1159/000118410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 01/05/2023]
Abstract
A new procedure for detecting departures from constancy of the parameters of a probabilistic model over a period of time is proposed. It basically consists of specification of a joint probability distribution for data and models and minimization of the total gain in information. In contrast to conventional techniques, this procedure can be used to determine both the number of different models and the positions of the points at which the switches from one model to another occur. It is demonstrated how this new method can be applied to the problem of identification of different stages of EEG background activity. The lengths of these stages might serve as indicators for drug effects in the EEG.
Collapse
Affiliation(s)
- E Reschenhofer
- Institute of Econometrics and Operations Research, University of Technology, Vienna, Austria
| | | | | |
Collapse
|
40
|
Deistler M, Prohaska O, Reschenhofer E, Vollmer R. Procedure for identification of different stages of EEG background activity and its application to the detection of drug effects. Electroencephalogr Clin Neurophysiol 1986; 64:294-300. [PMID: 2428576 DOI: 10.1016/0013-4694(86)90152-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A procedure for the detection of a change in EEG background activity is introduced. Here the time path of the relative power in the alpha band is modelled by fitting two lines, each corresponding to a different level of background activity. The jumping point between these two lines is estimated and serves as an indicator of drug effects.
Collapse
|
41
|
Rappelsberger P, Szirmai I, Vollmer R. [Analysis of the extension of epileptic discharges in the animal model]. EEG EMG Z Elektroenzephalogr Elektromyogr Verwandte Geb 1986; 17:47-54. [PMID: 3017681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The study was aimed at the enlightenment of intracortical spreading mechanisms in focal epileptic seizures produced by local application of Acetylcholine. Experiments were made in rabbits. Epi- and intracortical seizure potentials were recorded simultaneously with special electrodes. The recorded signals were analysed using computer aided methods. The results show, that the spreading of the pathological events does not take place continuously but by successive generation of "active zones" independent of the original focus produced by Acetylcholine. In the epicortical recordings, the development of a new focus is indicated by a functional uncoupling between the superficial layers of the cortical area to be involved and the momentary active focus. This functional uncoupling is due to an activation of the middle cortical layers of this area by the focus. As a first sign, high frequent potentials can be observed in the middle cortical layers accompanied by an amplitude decrease in the superficial layers. In the further development high negative discharges appear in the middle cortical layers which lead to characteristic surface positive potentials. This phase indicates that a new focus has developed, i.e. the discharges are no longer triggered by the previous focus. These processes continue as long as inactive cortical areas are available. From the obtained results it can be assumed with high probability that in contrast to previous assumptions the generation of a new epileptic focus is not initiated via superficial axon collaterals but that other cortical connections must be responsible. Additionally, it has to be taken into account that extra- and/or intracellular changes of ion concentrations as a consequence of the massive synaptic bombardment may be responsible for the independent discharges in the focus.
Collapse
|
42
|
Szpak CA, Johnston WW, Roggli V, Kolbeck J, Lottich SC, Vollmer R, Thor A, Schlom J. The diagnostic distinction between malignant mesothelioma of the pleura and adenocarcinoma of the lung as defined by a monoclonal antibody (B72.3). Am J Pathol 1986; 122:252-60. [PMID: 2418688 PMCID: PMC1888114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The correct distinction between malignant mesothelioma of the pleura and adenocarcinoma of the lung has become increasingly complex, with a variety of histochemical, immunohistochemical, and ultrastructural studies to be performed on biopsy material. The reliability of immunohistochemical studies has been hampered by the use of polyclonal antisera to "carcinoembryonic antigen (CEA)" and keratin. Hybridoma technology now offers monoclonal antibodies (MAbs) in unlimited quantity and standardized quality to selective ranges of specific antigenic determinants. MAb B72.3, generated against a membrane-enriched fraction of human metastatic breast carcinoma, was used to distinguish malignant mesothelioma of the pleura from adenocarcinoma of the lung in tissue sections and was compared in terms of diagnostic utility with polyclonal anti-keratin and anti-CEA to make the same distinction. Reactivity with MAb B72.3 in at least 10% of tumor cells or more was noted in 19 of 22 adenocarcinomas of the lung (P greater than 0.0001), whereas none of the 20 cases of malignant mesothelioma demonstrated comparable reactivity. Furthermore, MAb B72.3 showed no reactivity with benign mesothelial proliferations. MAb B72.3 thus appears to be an appropriate diagnostic adjunct capable of discriminating between these malignancies.
Collapse
|
43
|
Abstract
Confusion exists concerning the influence of pregnancy on survival in patients with malignant melanoma. To evaluate this problem a retrospective computer-aided study was performed of women in the child-bearing years treated for Stage I cutaneous melanoma at the Duke University Comprehensive Cancer Center. Fifty-eight women were identified who had melanoma arise during pregnancy (Group 1) and 43 patients were noted who became pregnant within 5 years of diagnosis of their melanoma (Group 2). Appropriate control groups matched for the clinical variables of age, primary site, and stage of disease and the pathologic variables of Clark's Level, tumor thickness, ulceration, and histologic type were selected from the cohort of 2938 melanoma patients seen at Duke. Actuarial survivals for Group 1 and 2 patients did not differ from their respective controls, although the small number of deaths in each group resulted in wide confidence intervals. When actuarial disease-free intervals were plotted, there was a significant difference between women who had melanoma develop during pregnancy when compared to their controls (P = 0.04). In a multivariate regression analysis, after adjustment for the influence of the more significant prognostic factors for Stage 1 melanoma, including Clark's Level, ulceration and tumor thickness, the effect of pregnancy on disease-free interval became more apparent (P = 0.02). No difference in actuarial disease-free interval was noted in the melanoma patients who elected to become pregnant within 5 years of diagnosis (P = 0.31). A multivariate regression analysis confirmed this finding. These data indicate that although an intercurrent melanoma during pregnancy has a worse prognosis than the control groups, once a woman has been diagnosed as having a cutaneous melanoma, a subsequent pregnancy has no effect on recurrence rate or survival.
Collapse
|
44
|
Lowenbraun S, Birch R, Buchanan R, Krauss S, Durant J, Perez C, Mill W, Vollmer R, Ogden L. Combination chemotherapy in small cell lung carcinoma. A randomized study of two intensive regimens. Cancer 1984; 54:2344-50. [PMID: 6093979 DOI: 10.1002/1097-0142(19841201)54:11<2344::aid-cncr2820541106>3.0.co;2-c] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
From April, 1979 to November, 1981, 293 patients with small cell lung carcinoma (SCLC) were entered on a randomized, controlled study comparing the two induction regimens of high-dose CAV (HD-CAV) (cyclophosphamide [CTX] 1200 mg/m2, doxorubicin [ADR] 70 mg/m2 and vincristine [VCR] 1 mg/m2 intravenously (IV) on days 1 and 21) versus, conventional-dose CAV + VP-16 (etoposide) (CAV-VP) (CTX 1000 mg/m2, ADR 40 mg/m2, VCR 1 mg/m2 IV on days 1 and 21 with VP-16 100 mg/m2 on days 1-3, and 21-23). Responding and stable patients were continued on conventional-dose CAV for 5 consolidation courses. Prophylactic brain irradiation delivered after the first consolidation course in responders was optional. Patients were included in the study if they had extensive disease (i.e., beyond one hemithorax), no prior chemotherapy, or radiotherapy and performance status of 50 or above. After 2 induction courses, 215 cases are evaluable. Of these, 76 of 106 (72%) patients treated with HD-CAV have responded (greater than 50% regression), including 13 complete responders (CRs) versus 80 of 108 (74%) patients on CAV-VP, including 15 CRs. Of the 130 evaluable patients who have completed consolidation (HD-CAV, 65; CAV-VP, 65), an additional 22 patients achieved CR (HD-CAV, 12; CAV-VP, 10) for an overall CR rate of 24%. Median duration of remission was 33.6 weeks for HD-CAV and 35.6 weeks for CAV-VP (P = 0.61). Median duration of complete response for HD-CAV was 33.8 weeks and for CAV-VP 36.7 weeks (P = 0.81). Survival curves were similar for the two regimens, with medians of 42.1 weeks for HD-CAV and 42.3 weeks for CAV-VP (P = 0.35). Survival correlated with performance status and quality of response. As anticipated, the major toxicity for both induction regimens was leukopenia. During induction, granulocyte nadirs of less than 500/mm3 occurred in 81% of patients on HD-CAV and 77% of patients on CAV-VP. Thus, dose intensification appears to produce high response rates and modest complete response rates in extensive SCLC, but it does not appear to improve materially survival compared to prior reports of conventional-dose therapy.
Collapse
|
45
|
|
46
|
|
47
|
Jellinger K, Volc D, Grisold W, Flament H, Vollmer R, Weiss R. [Combined treatment of malignant gliomas]. Wien Klin Wochenschr 1983; 95:407-16. [PMID: 6613138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A controlled study of 226 age-matched patients with histologically proven grade 3 and 4 supratentorial gliomas with maximum feasible tumour resection, postoperative Karnofsky performance over 50 and minimum survival of 8 weeks compares the results of supportive care (45 cases), high-dose irradiation of 40 to 66 Gy (59 cases), COMP protocol (CCNU, procarbazine, vincristine, methotrexate, prednisone in 15 day cycles-42 cases) and simultaneous irradiation and COMP chemotherapy (80 cases including 30 survivors). Median recurrent-free intervals in the treatment groups (7 to 11.7 months) were significantly longer than after supportive care (4.4 months). Median survival with supportive care (6.7 months) was significantly shorter than after radiation or COMP treatment (11.7 and 12.3 months) and 14.9 to over 19.9 months with combined treatment, where the two-year survival rates were 33 and 67% (for survivors), and the 3-year survival rates 13 to 30%. Toxic side effects of multimodality treatment were more frequent than after chemotherapy. In addition to space-occupying intracranial cysts often simulating tumour recurrence (12%) and rare radiation necrosis, about 15% of long-term survivors developed progressive intellectual dysfunction with brain atrophy, in the absence of tumour regrowth. Despite some promising results of multimodality approaches towards the management of malignant supratentorial gliomas, the overall results are unsatisfactory and need further optimization.
Collapse
|
48
|
Abstract
This report presents the interesting case of a 50-year-old white man with an unusual benign tumor composed predominantly of a proliferation of atypical endothelial cells combined with a variable inflammatory response. This case represents an instance of the recently renamed entity "histiocytoid hemangioma" in which two organ systems are involved. Both skin and bone showed typical lesions. No physical connection jointed the separate lesions. The results of examination by light microscopy, electron microscopy, and immunoperoxidase examination for lysozyme and Factor VIII are reported. The significance of this case is that it supports the concept of classifying similar vascular lesions, despite varied organ system origin, into a single entity, the histiocytoid hemangioma.
Collapse
|
49
|
Vollmer R, Matejcek M, Greenwood C, Grisold W, Jellinger K. Correlation between EEG changes indicative of sedation and subjective responses. Neuropsychobiology 1983; 10:249-53. [PMID: 6676678 DOI: 10.1159/000118019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The central activity of ketotifen ( Zaditen ), a benzocycloheptathiophene derivative for use in the prophylaxis of asthma, was determined by quantitative pharmaco-EEG in 7 healthy volunteers in a single-blind trial. During the 1st week of the trial, placebo was given twice daily followed by ketotifen 1 mg twice daily for 3 weeks. Placebo was again given for a further week. 15-min resting EEGs were taken immediately before and 3 and 6 h after medication on 8 defined days during the study, and the subjects were asked for side effects. Lead O2-Cz was analyzed by spectral analysis, and the relative power of the delta, theta, and fast and slow alpha bands as well as the dominant alpha frequency were calculated. The mean of each of these parameters was calculated per subject for each of the three measurements on each study day and compared with the baseline by means of one-way analysis of variance. A statistically significant slowing of the dominant alpha frequency, a decrease of the relative power of the fast alpha activity, and an increase of the relative power of the theta rhythm were found. These effects, indicative of a mild sedation, were highest during the 1st week of treatment with ketotifen, with a peak at the 3rd day, and gradually decreased thereafter. In contrast to the sensitive pharmaco-EEG method, none of the subjects complained of sedation or tiredness while taking ketotifen.
Collapse
|
50
|
Grisold W, Jellinger K, Vollmer R. [Schilder's disease with clinical recovery in a woman aged 54 years (author's transl)]. Nervenarzt 1982; 53:164-7. [PMID: 7078693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|