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Seehusen F, Scherrer S. Morphological and molecular characterisation of a new strain of Mycobacterium avium subsp. paratuberculosis in Swiss goats. J Comp Pathol 2019. [DOI: 10.1016/j.jcpa.2018.10.118] [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: 10/27/2022]
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Salathé CR, Melloh M, Crawford R, Scherrer S, Boos N, Elfering A. Treatment Efficacy, Clinical Utility, and Cost-Effectiveness of Multidisciplinary Biopsychosocial Rehabilitation Treatments for Persistent Low Back Pain: A Systematic Review. Global Spine J 2018; 8:872-886. [PMID: 30560041 PMCID: PMC6293434 DOI: 10.1177/2192568218765483] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
STUDY DESIGN Systematic review. OBJECTIVES To review the current literature on the treatment efficacy, clinical utility, and cost-effectiveness of multidisciplinary biopsychosocial rehabilitation (MBR) for patients suffering from persistent (nonspecific) lower back pain (LBP) in relation to pain intensity, disability, health-related quality of life, and work ability/sick leave. METHODS We carried out a systematic search of Web of Science, Cochrane Library, PubMed Central, EMBASE, and PsycINFO for English- and German-language literature published between January 2010 and July 2017. Study selection consisted of exclusion and inclusion phases. After screening for duplication, studies were excluded on the basis of criteria covering study design, number of participants, language of publication, and provision of information about the intervention. All the remaining articles dealing with the efficacy, utility, or cost-effectiveness of intensive (more than 25 hours per week) MBR encompassing at least 3 health domains and cognitive behavioral therapy-based psychological education were included. RESULTS The search retrieved 1199 publications of which 1116 were duplicates or met the exclusion criteria. Seventy of the remaining 83 articles did not meet the inclusion criteria; thus 13 studies were reviewed. All studies reporting changes in pain intensity or disability over 12 months after MBR reported moderate effect sizes and/or p-values for both outcomes. The effects on health-related quality of life were mixed, but MBR substantially reduced costs. Overall MBR produced an enduring improvement in work ability despite controversy and variable results. CONCLUSIONS MBR is an effective treatment for nonspecific LBP, but there is room for improvement in cost-effectiveness and impact on sick leave, where the evidence was less compelling.
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Affiliation(s)
| | - Markus Melloh
- Zurich University of Applied Sciences, Winterthur, Switzerland
- Curtin University, Bentley, Western Australia, Australia
- The University of Western Australia, Perth, Western Australia,
Australia
| | | | | | - Norbert Boos
- Prodorso Centre for Spinal Medicine, Zurich, Switzerland
| | - Achim Elfering
- University of Bern, Bern, Switzerland
- University of Geneva, Geneva, Switzerland
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Ghielmetti G, Friedel U, Scherrer S, Sarno E, Landolt P, Dietz O, Hilbe M, Zweifel C, Stephan R. Non-tuberculousMycobacteriaisolated from lymph nodes and faecal samples of healthy slaughtered cattle and the abattoir environment. Transbound Emerg Dis 2017; 65:711-718. [DOI: 10.1111/tbed.12793] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Indexed: 12/13/2022]
Affiliation(s)
- G. Ghielmetti
- Institute of Veterinary Bacteriology; Swiss Reference Laboratory for bovine tuberculosis; Vetsuisse Faculty University of Zurich; Zurich Switzerland
| | - U. Friedel
- Institute of Veterinary Bacteriology; Swiss Reference Laboratory for bovine tuberculosis; Vetsuisse Faculty University of Zurich; Zurich Switzerland
| | - S. Scherrer
- Institute of Veterinary Bacteriology; Swiss Reference Laboratory for bovine tuberculosis; Vetsuisse Faculty University of Zurich; Zurich Switzerland
| | - E. Sarno
- Institute for Food Safety and Hygiene; Vetsuisse Faculty University of Zurich; Zurich Switzerland
| | - P. Landolt
- Institute of Veterinary Bacteriology; Swiss Reference Laboratory for bovine tuberculosis; Vetsuisse Faculty University of Zurich; Zurich Switzerland
| | - O. Dietz
- Institute of Veterinary Bacteriology; Swiss Reference Laboratory for bovine tuberculosis; Vetsuisse Faculty University of Zurich; Zurich Switzerland
| | - M. Hilbe
- Institute of Veterinary Pathology; Vetsuisse Faculty University of Zurich; Zurich Switzerland
| | - C. Zweifel
- Institute for Food Safety and Hygiene; Vetsuisse Faculty University of Zurich; Zurich Switzerland
| | - R. Stephan
- Institute for Food Safety and Hygiene; Vetsuisse Faculty University of Zurich; Zurich Switzerland
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Moussa M, Banakh O, Wehrle-Haller B, Fontana P, Scherrer S, Cattani M, Wiskott A, Durual S. TiN x O y coatings facilitate the initial adhesion of osteoblasts to create a suitable environment for their proliferation and the recruitment of endothelial cells. ACTA ACUST UNITED AC 2017; 12:025001. [PMID: 28244429 DOI: 10.1088/1748-605x/aa57a7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Titanium-nitride-oxide coatings (TiN x O y ) improve osseointegration of endosseous implants. The exact mechanisms by which these effects are mediated are poorly understood except for an increase of osteoblast proliferation while a high degree of differentiation is maintained. One hypothesis holds that TiN x O y facilitates the initial spreading and adhesion of the osteoblasts. The aim of this work was to investigate the molecular mechanisms of osteoblast adhesion on TiN x O y as compared to microrough titanium SLA. A global view of the osseointegrative process, that is, taking into account other cell groups, especially endothelial cells, is also presented. To this aim, gene expression and focal adhesion analysis, cocultures and wound assays were performed early after seeding, from 6 h to 3 days. We demonstrated that TiN x O y coatings enhance osteoblast adhesion and spreading when compared to the standard microrough titanium. The integrin β1, either in association with α1 or with α2 plays a central role in these mechanisms. TiN x O y coatings optimize the process of osseointegration by acting at several levels, especially by upregulating osteoblast adhesion and proliferation, but also by supporting neovascularization and the development of a suitable inflammatory environment.
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Affiliation(s)
- M Moussa
- Division of fixed prosthodontics and biomaterials, University clinics of dental medicine, University of Geneva, Switzerland
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Rocca GT, Saratti CM, Cattani-Lorente M, Feilzer AJ, Scherrer S, Krejci I. The effect of a fiber reinforced cavity configuration on load bearing capacity and failure mode of endodontically treated molars restored with CAD/CAM resin composite overlay restorations. J Dent 2015; 43:1106-1115. [PMID: 26149065 DOI: 10.1016/j.jdent.2015.06.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/23/2015] [Accepted: 06/25/2015] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVES To evaluate the fracture strength and the mode of failure of endodontically treated molars restored with CAD/CAM overlays with fiber reinforced composite build-up of the pulp chamber. METHODS 40 Devitalized molars were cut over the CEJ and divided into five groups (n=8). The pulp chamber area was filled with: group 0 (control), no resin build-up; group 1, hybrid composite build-up (G-aenial posterior, GC); group 2, as in group 1 but covered with 3 nets of bi-directional E-glass fibers (EverStickNET, Stick Tech Ltd.); group 3, a FRC resin (EverX posterior, GC); group 4, as in group 3 but covered by the bi-directional fibers. The crowns were restored with CAD-CAM composite restorations (Lava Ultimate, 3M ESPE). Maximum fracture loads were recorded in Newton and data were analyzed using Kruskal-Wallis test (p<0.05). Fragments were analyzed using SEM. RESULTS The mean static loads in Newton were: group 0: 2448 (546); group 1: 2817 (873); group 2: 2128 (952); group 3: 2429 (1091); group 4: 2577 (833). No significant differences were found between the groups (p>0.05). All specimens fractured in a catastrophic way, under the CEJ. The main crack evolved in the corono-apical direction. In groups 2 and 4 secondary fracture paths with apico-coronal direction were detected close to the bi-directional fibers' layer. CONCLUSIONS For the restoration of endodontically treated molars, the incorporation of FRCs did not influence the load-bearing capacity of the tooth-restoration complex. The SEM analysis showed a low ability of the bi-directional fibers net in deviating the fracture but this effect was not sufficient to lead more favorable fracture patterns, over the CEJ. CLINICAL SIGNIFICANCE The use of FRCs to reinforce the "core" of devitalized molars against vertical fractures under static loads seems useless when the thickness of the CAD/CAM composite overlay restoration is high.
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Affiliation(s)
- G T Rocca
- Division of Cariology and Endodontology, School of Dentistry, University of Geneva, Geneva, Switzerland.
| | - C M Saratti
- Division of Cariology and Endodontology, School of Dentistry, University of Geneva, Geneva, Switzerland
| | - M Cattani-Lorente
- Division of Prosthodontics and Biomaterials, School of Dentistry, University of Geneva, Geneva, Switzerland
| | - A J Feilzer
- Department of Dental Materials Science, ACTA, Amsterdam, The Netherlands
| | - S Scherrer
- Division of Prosthodontics and Biomaterials, School of Dentistry, University of Geneva, Geneva, Switzerland
| | - I Krejci
- Division of Cariology and Endodontology, School of Dentistry, University of Geneva, Geneva, Switzerland
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Magouras I, Hunninghaus J, Scherrer S, Wittenbrink MM, Hamburger A, Stärk KDC, Schüpbach-Regula G. Coxiella burnetii Infections in Small Ruminants and Humans in Switzerland. Transbound Emerg Dis 2015; 64:204-212. [PMID: 25922932 DOI: 10.1111/tbed.12362] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Indexed: 11/27/2022]
Abstract
The recent Q fever epidemic in the Netherlands raised concerns about the potential risk of outbreaks in other European countries. In Switzerland, the prevalence of Q fever in animals and humans has not been studied in recent years. In this study, we describe the current situation with respect to Coxiella (C.) burnetii infections in small ruminants and humans in Switzerland, as a basis for future epidemiological investigations and public health risk assessments. Specific objectives of this cross-sectional study were to (i) estimate the seroprevalence of C. burnetii in sheep and goats, (ii) quantify the amount of bacteria shed during abortion and (iii) analyse temporal trends in human C. burnetii infections. The seroprevalence of C. burnetii in small ruminants was determined by commercial ELISA from a representative sample of 100 sheep flocks and 72 goat herds. Herd-level seroprevalence was 5.0% (95% CI: 1.6-11.3) for sheep and 11.1% (95% CI: 4.9-20.7) for goats. Animal-level seroprevalence was 1.8% (95% CI: 0.8-3.4) for sheep and 3.4% (95% CI: 1.7-6) for goats. The quantification of C. burnetii in 97 ovine and caprine abortion samples by real-time PCR indicated shedding of >104 bacteria/g in 13.4% of all samples tested. To our knowledge, this is the first study reporting C. burnetii quantities in a large number of small ruminant abortion samples. Annual human Q fever serology data were provided by five major Swiss laboratories. Overall, seroprevalence in humans ranged between 1.7% and 3.5% from 2007 to 2011, and no temporal trends were observed. Interestingly, the two laboratories with significantly higher seroprevalences are located in the regions with the largest goat populations as well as, for one laboratory, with the highest livestock density in Switzerland. However, a direct link between animal and human infection data could not be established in this study.
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Affiliation(s)
- I Magouras
- Veterinary Public Health Institute, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - J Hunninghaus
- Veterinary Public Health Institute, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - S Scherrer
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - M M Wittenbrink
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - A Hamburger
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | | | - G Schüpbach-Regula
- Veterinary Public Health Institute, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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Jäncke L, Brügger E, Brummer M, Scherrer S, Alahmadi N. Verbal learning in the context of background music: no influence of vocals and instrumentals on verbal learning. Behav Brain Funct 2014; 10:10. [PMID: 24670048 PMCID: PMC3986892 DOI: 10.1186/1744-9081-10-10] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 03/19/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Whether listening to background music enhances verbal learning performance is still a matter of dispute. In this study we investigated the influence of vocal and instrumental background music on verbal learning. METHODS 226 subjects were randomly assigned to one of five groups (one control group and 4 experimental groups). All participants were exposed to a verbal learning task. One group served as control group while the 4 further groups served as experimental groups. The control group learned without background music while the 4 experimental groups were exposed to vocal or instrumental musical pieces during learning with different subjective intensity and valence. Thus, we employed 4 music listening conditions (vocal music with high intensity: VOC_HIGH, vocal music with low intensity: VOC_LOW, instrumental music with high intensity: INST_HIGH, instrumental music with low intensity: INST_LOW) and one control condition (CONT) during which the subjects learned the word lists. Since it turned out that the high and low intensity groups did not differ in terms of the rated intensity during the main experiment these groups were lumped together. Thus, we worked with 3 groups: one control group and two groups, which were exposed to background music (vocal and instrumental) during verbal learning. As dependent variable, the number of learned words was used. Here we measured immediate recall during five learning sessions (recall 1 - recall 5) and delayed recall for 15 minutes (recall 6) and 14 days (recall 7) after the last learning session. RESULTS Verbal learning improved during the first 5 recall sessions without any strong difference between the control and experimental groups. Also the delayed recalls were similar for the three groups. There was only a trend for attenuated verbal learning for the group passively listened to vocals. This learning attenuation diminished during the following learning sessions. CONCLUSIONS The exposure to vocal or instrumental background music during encoding did not influence verbal learning. We suggest that the participants are easily able to cope with this background stimulation by ignoring this information channel in order to focus on the verbal learning task.
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Affiliation(s)
- Lutz Jäncke
- Psychological Institute, Department of Neuropsychology, University of Zurich, Zurich, Switzerland.
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Prohaska S, Pflüger V, Ziegler D, Scherrer S, Frei D, Lehmann A, Wittenbrink M, Huber H. MALDI-TOF MS for identification of porcine Brachyspira
species. Lett Appl Microbiol 2013; 58:292-8. [DOI: 10.1111/lam.12189] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 10/09/2013] [Accepted: 10/28/2013] [Indexed: 12/01/2022]
Affiliation(s)
- S. Prohaska
- Vetsuisse Faculty; Institute of Veterinary Bacteriology; University of Zurich; Zurich Switzerland
| | | | | | - S. Scherrer
- Vetsuisse Faculty; Institute of Veterinary Bacteriology; University of Zurich; Zurich Switzerland
| | - D. Frei
- Vetsuisse Faculty; Institute of Veterinary Bacteriology; University of Zurich; Zurich Switzerland
| | - A. Lehmann
- Vetsuisse Faculty; Institute of Veterinary Bacteriology; University of Zurich; Zurich Switzerland
| | - M.M. Wittenbrink
- Vetsuisse Faculty; Institute of Veterinary Bacteriology; University of Zurich; Zurich Switzerland
| | - H. Huber
- Vetsuisse Faculty; Institute of Veterinary Bacteriology; University of Zurich; Zurich Switzerland
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Abstract
AbstractChevrel phases have an open lattice with large voids in which cations can be inserted. These cations are good scattering centers for phonons. The thermal conductivity of these compounds must be low. Chevrel phases are generally metallic, but we calculated the density of states of several compounds and we found that Zn2Mo6Se8, Cd2Mo6Se8, TiMo6Se8 are semiconducting whereas SnMo6Se8, Cu2Mo6Se8 and CrMo6Se8 are metallic. We are currently trying to synthesize Zn2Mo6Se8 by different ways.
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Scherrer S, Diniz IR, Morais HC. Climate and host plant characteristics effects on lepidopteran caterpillar abundance on Miconia ferruginata DC and Miconia pohliana Cogn (Melastomataceae). BRAZ J BIOL 2010; 70:103-9. [PMID: 20231965 DOI: 10.1590/s1519-69842010000100014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Accepted: 08/27/2008] [Indexed: 11/21/2022] Open
Abstract
Folivore cerrado caterpillars are found on their host species in low frequencies, which vary between plants and throughout the year. We analysed the effects of climatic variation and of the characteristics of two host species (Miconia, Melastomataceae) on caterpillar abundance. The work was carried out in a cerrado sensu stricto area in Brasília, Federal District, Brazil, from May 1998 to September 1999. One hundred plants of each species were inspected monthly. All caterpillars found were collected and raised in the laboratory with Miconia leaves as food sources. Climatic data for the study area and plant characteristics such as local density, spatial distribution, foliar phenology, leaf pilosity and nutritional content were used to test the effects on caterpillar abundance. Less than 10% of the plants had larvae. Caterpillars were more frequent and abundant in M. pohliana, which was also present at higher densities than M. ferruginata. Low caterpillar frequency in host plants and an abundance peak during the dry season are consistent patterns for different cerrado Lepidoptera larvae. This abundance peak, however, is not coincident with higher leaf production in host species. We suggest that M. pohliana's higher local density and better leaf digestibility can account for the higher abundance of caterpillars in this species.
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Affiliation(s)
- S Scherrer
- Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, Brazil.
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Gaab J, Sonderegger L, Scherrer S, Ehlert U. Psychoneuroendocrine effects of cognitive-behavioral stress management in a naturalistic setting--a randomized controlled trial. Psychoneuroendocrinology 2006; 31:428-38. [PMID: 16330155 DOI: 10.1016/j.psyneuen.2005.10.005] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [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] [Received: 09/08/2005] [Revised: 10/18/2005] [Accepted: 10/21/2005] [Indexed: 11/17/2022]
Abstract
It is assumed that chronic or extensive release of cortisol due to stress has deleterious effects on somatic and psychological health, making interventions aiming to reduce and/or normalize cortisol secretion to stress of interest. Cognitive-behavioral stress management (CBSM) has repeatedly been shown to effectively reduce cortisol responses to acute psychosocial stress. However, the effects of CBSM on psychoneuroendocrine responses during "real-life" stress have yet not been examined in healthy subjects. Eight weeks before all subjects took an important academic exam, 28 healthy economics students were randomly assigned to four weekly sessions of cognitive behavioral stress management (CBSM) training or a waiting control condition. Psychological and somatic symptoms were repeatedly assessed throughout the preparation period. Salivary cortisol (cortisol awakening response and short circadian cortisol profile) was repeatedly measured at baseline and on the day of the exam. In addition, cognitive appraisal was assessed on the day of the exam. Subjects in the CBSM group showed significantly lower anxiety and somatic symptom levels throughout the period prior to the exam. On the day of the exam, groups differed in their cortisol awakening stress responses, with significantly attenuated cortisol levels in controls. Short circadian cortisol levels did not differ between groups. Interestingly, groups differed in their associations between cortisol responses before the exam and cognitive stress appraisal, with dissociation in controls but not in the CBSM group. The results show that CBSM reduces psychological and somatic symptoms and influences the ability to show a cortisol response corresponding to subjectively perceived stress. In line with current psychoneuroendocrine models, the inability to mount a cortisol response corresponding to the cognitive appraisal in controls could be a result of a dysregulated HPA axis, probably as a consequence of longlasting stress.
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Affiliation(s)
- J Gaab
- Institute of Psychology, University of Zürich, Clinical Psychology and Psychotherapy Zürichbergstr 43, CH-8044 Zürich, Switzerland.
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Pietrzak G, Curnier A, Botsis J, Scherrer S, Wiskott A, Belser U. A nonlinear elastic model of the periodontal ligament and its numerical calibration for the study of tooth mobility. Comput Methods Biomech Biomed Engin 2002; 5:91-100. [PMID: 12186719 DOI: 10.1080/10255840290032117] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [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: 10/28/2022]
Abstract
A large strain nonlinear elastic isotropic "split" law is proposed for modeling the behaviour of the periodontal ligament. This law allows for a better description of the stiffening response of this tissue and, concomitantly, for a more accurate calibration of its elastic properties. Indeed, fine finite element simulations of an upper human incisor attached to its surrounding alveolar bone by an intermediate layer of ligament were run using that "split" law for the ligament. A good correlation was established with available experimental data on such a tooth under axial loading. Values of 0.010-0.031 MPa for the initial Young's modulus and of 0.45-0.495 for Poisson's ratio were determined. A sensitivity analysis of the results with respect to material and numerical parameters of the model was also carried out. Finally, a comparison of the simulation results using this "split" law with standard ones obtained with the linear elastic law, shows a significant improvement.
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Affiliation(s)
- G Pietrzak
- Laboratoire de Mécanique Appliquée et d' Analyse de Fiabilité, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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Scherrer S, Iriarte A, Martinez-Carrion M. Stability and release requirements of the complexes of GroEL with two homologous mammalian aminotransferases. J Protein Chem 2000; 19:591-602. [PMID: 11233173 DOI: 10.1023/a:1007102402925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The mitochondrial (mAAT) and cytosolic (cAAT) homologous isozymes of aspartate aminotransferase are two relatively large proteins that in their nonnative states interact very differently with GroEL. MgATP alone can increase the rate of GroEL-assisted reactivation of cAAT, yet the presence of GroES is mandatory for mAAT. Addition of an excess of a denatured substrate accelerates reactivation of cAAT in the presence of GroEL, but has no effect on mAAT. These competition studies suggest that the more stringent substrate mAAT forms a thermodynamically stable complex with GroEL, while rebinding affects the slow reactivation kinetics of cAAT with GroEL alone. However, the competitor appears to accelerate the release of cAAT from GroEL, most likely by displacing bound cAAT from the GroEL cavity. Moreover, cAAT, but not mAAT, shows a time-dependent increase in protease resistance while bound to GroEL at low temperature. These results suggest that folding and release of cAAT from GroEL in the absence of cofactors may occur stepwise with certain interactions being broken and reformed until the protein escapes binding. The distinct behavior of these two isozymes most likely results from differences in the structure of the nonnative states that bind to GroEL.
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Affiliation(s)
- S Scherrer
- Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, 64110-2499, USA
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Scherrer S, De Vries OM, Dudler R, Wessels JG, Honegger R. Interfacial self-assembly of fungal hydrophobins of the lichen-forming ascomycetes Xanthoria parietina and X. ectaneoides. Fungal Genet Biol 2000; 30:81-93. [PMID: 10955910 DOI: 10.1006/fgbi.2000.1205] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [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: 11/22/2022]
Abstract
In the symbiotic phenotype of the lichen-forming ascomycetes Xanthoria parietina and X. ectaneoides, a conglutinate, hydrophilic cortex surrounds a system of aerial hyphae with hydrophobic wall surfaces. In X. parietina freeze-fracture electron microscopy showed that a rodlet layer covers the fungal and algal wall surfaces. Extracts of hot SDS-insoluble wall residues isolated from both species contained a protein that revealed a rodlet layer upon interfacial self-assembly. The N-terminal sequence of the 10-kDa protein of X. ectaneoides served to clone cDNA fragments of XEH1 (H1 of X. ectaneoides) and XPH1 (H1 of X. parietina) by RT-PCR. Genomic DNA blot analysis with both lichenized species and the aposymbiotically cultured symbionts of X. parietina showed that XPH1 and XEH1 are fungal single copy genes. The deduced amino acid sequences of the two encoded proteins were 96% identical and showed the characteristics of class I hydrophobins.
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Affiliation(s)
- S Scherrer
- Institute of Plant Biology, University of Zürich, Switzerland
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Schröder J, Silvestri S, Bubeck B, Karr M, Demisch S, Scherrer S, Geider FJ, Sauer H. D2 dopamine receptor up-regulation, treatment response, neurological soft signs, and extrapyramidal side effects in schizophrenia: a follow-up study with 123I-iodobenzamide single photon emission computed tomography in the drug-naive state and after neuroleptic treatment. Biol Psychiatry 1998; 43:660-5. [PMID: 9582999 DOI: 10.1016/s0006-3223(97)00442-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Animal and postmortem studies indicate that neuroleptic therapy may induce D2 dopamine receptor up-regulation in the basal ganglia. METHODS To address this phenomenon in a clinical study, we investigated the D2 dopamine receptor binding in 15 DSM-III-R schizophrenics in the drug-naive state and 3 days after completion of a standardized neuroleptic therapy (benperidol 12-16 mg/day, for 25 days) using single photon emission computed tomography (SPECT). SPECT scans were obtained 2 hours after intravenous injection of 185 MBq 123I-iodobenzamide. For analysis, basal ganglia to frontal cortex (BG/FC) ratios were calculated and the patient sample was subgrouped into patients with a favorable versus a poor treatment response. RESULTS Neuroleptic treatment led to decreased BG/FC ratios in patients with a favorable response, but increased ratios in the poor responders (df = 1, F = 4.1, p = .06). Changes of BG/FC ratios were significantly correlated with extrapyramidal side effects but not with neurological soft signs. CONCLUSIONS Our findings suggest that neuroleptic therapy may induce D2 dopamine receptor up-regulation in a subgroup of patients characterized by poor treatment response and pronounced extrapyramidal side effects.
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Affiliation(s)
- J Schröder
- Department of Psychiatry, University of Heidelberg, Germany
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Scherrer S. [Emergency care in the dental office. Continuing education of the Ecole de Médecine dentaire (Geneva): the emergency course 101 of 20 June 1997]. Schweiz Monatsschr Zahnmed 1997; 107:903-6. [PMID: 9411722] [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: 02/05/2023]
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Abstract
The role of the school nurse is changing to meet the increasing needs for health promotion and health education. However, the evolution is being hampered by the inefficient work practices involved in undertaking some of the more traditional tasks such as school screening. A survey questionnaire model of screening was developed and trialed with a sample of students and parents and then compared with the results of the more traditional one to one screening programme. The questionnaire survey model was evaluated for accuracy and efficiency against the traditional screening model. The questionnaire method exhibited a relatively low error rate and required one third of the time to complete when compared with the traditional screening programme. The implications of these findings as well as the advantages and limitations of each model are examined in the discussion.
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Affiliation(s)
- S Scherrer
- Macquarie Health District, Public Health Unit, Dubbo, New South Wales, Australia
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Devaux X, Brochin F, Dauscher A, Lenoir B, Martin-Lopez R, Scherrer H, Scherrer S. Production of ultrafine powders of BiSb solid solution. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0965-9773(97)00012-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Scherrer S. [Alternatives to amalgam: taking the biophysical factors into consideration in the choice of restoration material. The annual congress of the Academy of Dental Materials (ADM) of 30 October to 2 November 1996 at Munich]. Schweiz Monatsschr Zahnmed 1997; 107:264-6. [PMID: 9273690] [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: 02/05/2023]
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Scherrer S, Robas N, Zouheiry H, Branlant G, Branlant C. Periplasmic aggregation limits the proteolytic maturation of the Escherichia coli penicillin G amidase precursor polypeptide. Appl Microbiol Biotechnol 1994; 42:85-91. [PMID: 7765824 DOI: 10.1007/bf00170229] [Citation(s) in RCA: 20] [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: 01/27/2023]
Abstract
The Escherichia coli penicillin G amidase (PGA), which is a key enzyme in the production of penicillin G derivatives is generated from a precursor polypeptide by an unusual internal maturation process. We observed the accumulation of the PGA precursor polypeptide in the insoluble material recovered after sonication of recombinant E. coli JM109 cells grown at 26 degrees C. The aggregated nature of the accumulated molecules was demonstrated using detergents and chaotropic agents in solubilization assays. The periplasmic location of the aggregates was shown by trypsin-accessibility experiments performed on the spheroplast fraction. Finally, we showed that addition of sucrose or glycerol in the medium strongly reduces this periplasmic aggregation and as a consequence PGA production is substantially increased. Thus, periplasmic aggregation of the PGA precursor polypeptide limits PGA production by recombinant E. coli and this limitation can be overcome by addition in the medium of a non-metabolizable sugar, such as sucrose, or of glycerol.
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Affiliation(s)
- S Scherrer
- Laboratoire d'Enzymologie et de Génie Génétique, Université de Nancy I, URA CNRS 457, Vandoeuvre-Les-Nancy, France
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Beucher E, Lenglet M, Weber S, Scherrer S. Oxidation mechanisms on ?-brasses (10 and 30 at.% Zn) by optical methods and SIMS. SURF INTERFACE ANAL 1992. [DOI: 10.1002/sia.740180907] [Citation(s) in RCA: 4] [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: 11/09/2022]
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Borchardt G, Scherrer H, Weber S, Scherrer S. Local in-depth analysis of ceramic materials by neutral beam secondary ion mass spectrometry. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/0020-7381(80)85049-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Scherrer S, Haldimann B, Küpfer A, Reubi F, Bircher J. Hepatic metabolism of aminopyrine in patients with chronic renal failure. Clin Sci Mol Med 1978; 54:133-40. [PMID: 620502 DOI: 10.1042/cs0540133] [Citation(s) in RCA: 8] [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: 12/23/2022]
Abstract
1. To evaluate potential alterations in hepatic metabolism of drugs occurring in patients with renal insufficiency the fate of aminopyrine was studied in 17 patients with chronic renal failure and in 27 normal subjects. 2. Although patients with chronic renal failure exhibited large variations, their aminopyrine plasma disappearance times (mean 0.62 +/- SD 0.24 h-1) were significantly higher than those found in normal subjects (0.30 +/- 0.07 h-1, P less than 0.002). 3. 14CO2 derived from [dimethylamine-14C]aminopyrine disappeared from breath more rapidly in patients with chronic renal failure and a history of analgesic abuse (0.40 +/- 0.04 h-1) than in control subjects (0.22 +/- 0.03 h-1, P less than 0.01) and in other patients with chronic renal failure (0.24 +/- 0.04 h-1). 4. Dialysis treatment and serum creatinine concentrations were not correlated with the rates of aminopyrine metabolism. Two additional patients, however, with combined renal and hepatic disease, exhibited markedly slowed rates of aminopyrine demethylation. 5. Although chronic renal failure by itself might not alter microsomal drug metabolism it is concluded that, in patients with a history of abuse of phenacetin-containing analgesics, marked acceleration in aminopyrine N-demethylation may be observed.
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