26
|
Rojas J, Hamilton R, Luminais C, Siegel S. Investigating the Neurophysiological Effects of Direct Current Stimulation (IN6-1.005). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.in6-1.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
27
|
|
28
|
Hawkes RC, Fryer TD, Siegel S, Ansorge RE, Carpenter TA. Preliminary evaluation of a combined microPET-MR system. Technol Cancer Res Treat 2010; 9:53-60. [PMID: 20082530 DOI: 10.1177/153303461000900106] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
There are many motivations for adding simultaneously acquired MR images to PET scanning. The most straight forward are, superior registration of MR and PET images, the addition of morphological detail when there is non-rigid motion and for pre-clinical studies simultaneous imaging could lead to a significant reduction in the time that animals are required to be anesthetised. In addition simultaneous MR has the potential to provide accurate motion correction for PET image reconstruction. For functional imaging simultaneous acquisition is required to assess the subject in the same physiological state, such as acute stroke studies. The elimination of the additional radiation associated with combining CT with PET, by providing anatomic detail with MR, would be a crucial advantage for cancer screening. Combining the two instruments necessitates some engineering tradeoffs, especially associated with the use of the highly developed photomultiplier tube (PMT) used for light amplification, because of its incompatibility with strong magnetic fields. Our approach is to provide a split in the magnet and gradients to locate the magnetic sensitive components, the PMTs, in regions of low magnetic field, leaving only the essential PET components, the scintillator blocks, in the strong magnetic field region. The crystals are coupled to the PMTs by extending the optical fibres. A further advantage accrues by moving the PET electronics out of the region seen by the MR radio-frequency (RF) and gradient coils as electromagnetic interference effects between the PET and MR systems, which could cause artefacts in either modality, are eliminated. Here we describe a preliminary evaluation of the system, which is essentially a microPET Focus-120 located in a 1T split magnet, and compare its performance to previous microPET instruments.
Collapse
|
29
|
Siegel S, Dittrich R, Vollmann J. Ethical opinions and personal attitudes of young adults conceived by in vitro fertilisation. JOURNAL OF MEDICAL ETHICS 2008; 34:236-240. [PMID: 18375672 DOI: 10.1136/jme.2007.020487] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
BACKGROUND Today in vitro fertilisation (IVF) is a widespread and important technique of reproductive medicine. When the technique was first used, it was considered ethically controversial. This is the first study conducted of adult IVF-offspring in order to learn about their ethical opinions and personal attitudes towards this medical technology. METHODS We recruited the participants from the first cases of in vitro fertilisation in Germany at the Gynaecological Clinic of the University Hospital Erlangen. Our qualitative interview study consisted of in-depth, face-to-face interviews with 16 adults who had been conceived by IVF. Our data was analysed with methods of Grounded Theory. RESULTS For these adults, the most important factor influencing their personal attitudes towards IVF was the knowledge that they were deeply wanted children. The artificiality of their conception seemed irrelevant for their ethical opinion. All participants mentioned that it was important for them to be informed about the circumstances of their conception by their parents. CONCLUSIONS IVF seems to be a medical technique which, although it affects intimate aspects of human existence, can be integrated into the lives of the affected persons without any great difficulties. The findings suggest that parents should inform their children about their fertilisation at an early age and as part of a process over time, not only on a single occasion. Physicians should advise IVF-parents accordingly.
Collapse
|
30
|
Rosenberg R, Devenney W, Siegel S, Dan N. Anomalous Release of Hydrophilic Drugs from Poly(ϵ-caprolactone) Matrices. Mol Pharm 2007; 4:943-8. [DOI: 10.1021/mp700097x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
31
|
Lin ST, Siegel S. Stereochemistry and the use of H2/D2 mixtures as probes into the mechanism of hydrogenations catalyzed by cationic rhodium (DIPHOS) complexes. KINETICS AND CATALYSIS 2006. [DOI: 10.1134/s0023158406010137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
32
|
Lin ST, Siegel S. Addition of H2-D2 Mixtures to 2-Butyne and Norbornene Catalyzed by Solutions of Chlorotris(triphenylphosphine)rhodium(I), Hydridocarbonyltris(triphenylphosphine)rhodium(I), and Hydridotetrakis(5-phenyl-5-H-dibenzophosphole)rhodium(I). KINETICS AND CATALYSIS 2005. [DOI: 10.1007/s10975-005-0146-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
33
|
Siegel S, Vollhardt D, Cadenhead D. Effect of the hydroxy group position on the monolayer characteristics of hydroxypalmitic acids. Colloids Surf A Physicochem Eng Asp 2005. [DOI: 10.1016/j.colsurfa.2004.09.040] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
34
|
Siegel S, Steinmann J, Schmitz N, Stuhlmann R, Dreger P, Zeis M. Identification of a survivin-derived peptide that induces HLA-A*0201-restricted antileukemia cytotoxic T lymphocytes. Leukemia 2004; 18:2046-7. [PMID: 15470490 DOI: 10.1038/sj.leu.2403510] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
35
|
Vollhardt D, Siegel S, Cadenhead DA. Characteristic Features of Hydroxystearic Acid Monolayers at the Air/Water Interface. J Phys Chem B 2004. [DOI: 10.1021/jp048304l] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
36
|
Vollhardt D, Siegel S, Cadenhead DA. Effect of hydroxyl group position and system parameters on the features of hydroxystearic Acid monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:7670-7677. [PMID: 15323518 DOI: 10.1021/la049345b] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The characteristic features of hydroxystearic acid monolayers OH-substituted in the mid position of the alkyl chain deviate considerably from those of the usual nonsubstituted stearic acid. The phase behavior, domain morphology, and two-dimensional lattice structure of 9-, 11-, and 12-hydroxystearic acids are studied, using pi-A isotherms, Brewster angle microscopy (BAM), and grazing incidence X-ray diffraction (GIXD), to obtain detailed information on the effect of the exact position of the OH-substitution. The pi-A isotherms of all three hydroxyoctadecanoic acids have an extended flat plateau region, the extension of which only slightly decreases with the increase of temperature. At the same temperature, the extension of the plateau region increases and the plateau pressure decreases from 9-hydroxyoctadecanoic acid to 12-hydroxyoctadecanoic acid. The absolute -DeltaH and -DeltaS values for the phase transition increase slightly from 9-hydroxyoctadecanoic acid to 12- hydroxyoctadecanoic acid and indicate differences in the ordering of the condensed phase under consideration of the special reorientation mechanism of these bipolar amphiphiles at the fluid/condensed phase transition. The morphology of the condensed phase domains formed in the fluid/condensed coexistence region is specific for the position of the OH-substitution of the alkyl chain, just as the lattice structures of the condensed monolayer phase. 11-hydroxyoctadecanoic acid monolayers form centered rectangular lattices with the chain tilt toward the NNN (next nearest neighbor) direction, and 12-hydroxyoctadecanoic acid monolayers have an oblique lattice over the entire pressure range. A special feature of 9-hydroxystearic acid monolayers is the phase transition between two condensed phases observed in the pi-A isotherm of 5 degrees C at approximately 18 mN/m, where the centered rectangular lattice shows a NNN/NN transition. The morphology of the condensed phase domains formed in the fluid/condensed coexistence region, just as the lattice structures of the condensed monolayer phase, reveal the high specifity of the monolayer feature of the bipolar hydroxystearic acids OH-substituted in the mid position.
Collapse
|
37
|
Attin T, Siegel S, Buchalla W, Lennon AM, Hannig C, Becker K. Brushing Abrasion of Softened and Remineralised Dentin: An in situ Study. Caries Res 2003; 38:62-6. [PMID: 14684979 DOI: 10.1159/000073922] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2003] [Accepted: 06/12/2003] [Indexed: 11/19/2022] Open
Abstract
The aim of the present in situ study was to evaluate the effect of different periods of intra-oral remineralisation on the susceptibility of softened dentin to toothbrushing abrasion. Groups of 6 human dentin specimens (A-F) were recessed in the buccal aspects of intra-oral appliances which were worn for 21 days by 11 volunteers. The samples were demineralised twice a day extra-orally in the acidic beverage Sprite Light (pH 2.9) for 90 s. Subsequently, the dentin specimens were brushed at different times. Specimen A was brushed immediately after demineralisation. Specimens B-E were brushed after the intra-oral appliances had been worn for various periods in the mouth: specimen B for 10 min, C for 20 min, D for 30 min and E for 60 min. Specimen F was not brushed (control). After 21 days, dentin wear was measured with a profilometer. The following values (means +/- standard deviation) were recorded (microm): A, 23.6 +/- 16.7; B, 37.9 +/- 29.7; C, 31.8 +/- 26.5; D, 18.5 +/- 10.5; E, 15.3 +/- 11.6; F, 12.6 +/- 6.7. There was a statistically significantly increased dentin loss for groups A, B and C as compared to the controls (U test: p < 0.05). However, after intra-oral periods of 30 and 60 min, wear was not significantly higher than in unbrushed controls. It is concluded that for protection of dentin surfaces at least 30 min should elapse before toothbrushing after an erosive attack.
Collapse
|
38
|
Siegel S, Speitel T, Shiraki D, Fukumoto J. Effects of experimental hypogravity on peroxidase and cell wall constituents in the dwarf marigold. LIFE SCIENCES AND SPACE RESEARCH 2002; 16:105-9. [PMID: 11965654 DOI: 10.1016/b978-0-08-022022-2.50020-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Dwarf Marigolds grown from seed under experimental hypogravity are modified in lignin content, hemicellulose composition, and peroxidase activity. The two conditions used, clinostats and flotation, induced changes differing in magnitude but qualitatively similar. Most responses on clinostats required corrections for vertical axis rotational effects, thus limiting the value of these instruments in free-fall simulation. These findings extend earlier observations suggesting that increased peroxidase and decreased lignin are characteristic of growth under experimental hypogravity.
Collapse
|
39
|
Fainerman VB, Vollhardt D, Siegel S. Dynamics of a Mixed Monolayer Consisting of a Soluble Amphiphile and Its Insoluble 2D Condensing Homologue. J Phys Chem B 2002. [DOI: 10.1021/jp020035g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
40
|
Siegel S, Smith GV, Dmuchovsky B, Dubbell D, Halpern W. The Stereochemistry of the Hydrogenation of the Isomeric Xylenes and p-tert-Butyltoluene over a Platinum Catalyst1,2,3. J Am Chem Soc 2002. [DOI: 10.1021/ja00875a020] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
41
|
Siegel S, Hoenig D, Vollhardt D, Moebius D. Direct observation of three-dimensional transformation of insoluble monolayers. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100199a062] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
42
|
Whittaker AG, Moore DW, Siegel S. Interchange of cis and trans Chemical Shifts in Symmetrically Substituted Amides. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100793a506] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
43
|
Hoekstra HR, Siegel S, Fuchs LH, Katz JJ. The Uranium–Oxygen System:UO2.5 to U3O8. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j150524a010] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
44
|
Swepston PN, Lin ST, Hawkins A, Humphrey S, Siegel S, Cordes AW. Strained benzene rings: preparation and crystal structure of a dithiahexahydro[3.3]paracyclophane, S2C16H22. J Org Chem 2002. [DOI: 10.1021/jo00331a044] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
45
|
Reis AH, Willi C, Siegel S, Tani B. Molecular and crystal structure of bis(.mu.-acetato)-bis(norbornadiene)dirhodium(I): a catalyst for the isomerization of quadricyclane to norbornadiene. Inorg Chem 2002. [DOI: 10.1021/ic50197a029] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
46
|
Carnall WT, Siegel S, Ferraro JR, Tani B, Gebert E. New series of anhydrous double nitrate salts of the lanthanides. Structural and spectral characterization. Inorg Chem 2002. [DOI: 10.1021/ic50121a013] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
47
|
Parker LA, Siegel S. Modulation of the effects of rewarding drugs by ibogaine. THE ALKALOIDS. CHEMISTRY AND BIOLOGY 2002; 56:211-25. [PMID: 11705109 DOI: 10.1016/s0099-9598(01)56015-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
|
48
|
Kim JA, Siegel S. The role of cholecystokinin in conditional compensatory responding and morphine tolerance in rats. Behav Neurosci 2001. [PMID: 11439459 DOI: 10.1037//0735-7044.115.3.704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
As elaborated in the conditioning analysis of tolerance, cues present at the time of drug administration become associated with the drug effect. A particularly salient cue that may become associated with the drug effect is the pharmacological drug-onset cue inherent to drug administration. Drug-associated cues contribute to tolerance by eliciting a conditional compensatory response that attenuates the drug effect. For example, the early drug effect, having been paired with the subsequent larger drug effect, may elicit the release of antiopioid peptides that counter opioid effects. The role of a putative antiopioid peptide, cholecystokinin-8 (CCK), in the associative mechanisms of opiate tolerance was evaluated. The results of these experiments suggest that a CCK2 receptor antagonist attenuates both the expression of opiate tolerance and the conditional compensatory response hypothesized to mediate such tolerance.
Collapse
|
49
|
Vollhardt D, Brezesinski G, Siegel S, Emrich G. Phase Transition in Adsorbed Monolayers of Sodium Dodecyl Sulfate/Dodecanol Mixtures. J Phys Chem B 2001. [DOI: 10.1021/jp011753q] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
50
|
Siegel S, Paszkiewicz E, Kirkpatrick C, Hinkel B, Oleson K. Sacral nerve stimulation in patients with chronic intractable pelvic pain. J Urol 2001; 166:1742-5. [PMID: 11586214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
PURPOSE Transforamenal sacral nerve stimulation with an implantable neuroprosthetic device has been shown to benefit patients with chronic voiding dysfunction. In this study we measured the effectiveness of sacral nerve stimulation in 10 patients with chronic intractable pelvic pain. MATERIALS AND METHODS After successful percutaneous trial stimulation, a neuroprosthetic sacral nerve stimulation device was surgically implanted in 10 patients with chronic intractable pelvic pain. Leads were placed in the S3 and S4 foramen in 8 and 2 cases, respectively. Patients were evaluated throughout the study using a patient pain assessment questionnaire on a scale of 0-absent to 5-excruciating pain. Pain was assessed at baseline, during test stimulation, and 1, 3 and 6 months after surgical lead implantation. An additional long-term assessment was done at a median followup of 19 months. RESULTS Of the 10 patients with the implant 9 had a decrease in the severity of the worst pain compared to baseline at a median followup of 19 months. The number of hours of pain decreased from 13.1 to 6.9 at the same followup interval. There was also an average decrease in the rate of pain from 9.7 at baseline to 4.4 on a scale of 10-always to 0-never having pain. At a median of 19 months 6 of 10 patients reported significant improvement in pelvic pain symptomology. CONCLUSIONS These data imply that transforamenal sacral nerve stimulation can have beneficial effects on the severity and frequency of chronic intractable pelvic pain. Future clinical studies are necessary to determine the long-term effectiveness of this therapy.
Collapse
|