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Dahmardeh Z, Saadat M. Exploring the potential of standalone and tandem solar cells with Sb 2S 3 and Sb 2Se 3 absorbers: a simulation study. Sci Rep 2023; 13:22632. [PMID: 38114523 PMCID: PMC10730701 DOI: 10.1038/s41598-023-49269-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 09/28/2023] [Accepted: 12/06/2023] [Indexed: 12/21/2023] Open
Abstract
Thin-film antimony chalcogenide binary compounds are potential candidates for efficient and low-cost photovoltaic absorbers. This study investigates the performance of Sb2S3 and Sb2Se3 as photovoltaic absorbers, aiming to optimize their efficiency. The standalone Sb2S3 and Sb2Se3 sub-cells are analyzed using SCAPS-1D simulations, and then a tandem structure with Sb2S3 as the top-cell absorber and Sb2Se3 as the bottom-cell absorber is designed, using the filtered spectrum and the current matching technique. The optimal configuration for maximum efficiency is achieved by adjusting the thickness of the absorber layer. The results show that antimony chalcogenide binary compounds have great potential as photovoltaic absorbers, enabling the development of efficient and low-cost solar cells. A remarkable conversion efficiency of 22.2% is achieved for the optimized tandem cell structure, with absorber thicknesses of 420 nm and 1020 nm for the top and bottom sub-cells respectively. This study presents a promising approach towards high-performance tandem solar cells.
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Affiliation(s)
- Z Dahmardeh
- Department of Physics, University of Sistan and Baluchestan, Zahedan, Iran
| | - M Saadat
- Department of Physics, University of Sistan and Baluchestan, Zahedan, Iran.
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2
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Fernandes MC, Saadat M, Cauchy-Dubois P, Inamura C, Sirota T, Milliron G, Haj-Hariri H, Bertoldi K, Weaver JC. Mechanical and hydrodynamic analyses of helical strake-like ridges in a glass sponge. J R Soc Interface 2021; 18:20210559. [PMID: 34493089 DOI: 10.1098/rsif.2021.0559] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
From the discovery of functionally graded laminated composites, to near-structurally optimized diagonally reinforced square lattice structures, the skeletal system of the predominantly deep-sea sponge Euplectella aspergillum has continued to inspire biologists, materials scientists and mechanical engineers. Building on these previous efforts, in the present study, we develop an integrated finite element and fluid dynamics approach for investigating structure-function relationships in the complex maze-like organization of helical ridges that surround the main skeletal tube of this species. From these investigations, we discover that not only do these ridges provide additional mechanical reinforcement, but perhaps more significantly, provide a critical hydrodynamic benefit by effectively suppressing von Kármán vortex shedding and reducing lift forcing fluctuations over a wide range of biologically relevant flow regimes. By comparing the disordered sponge ridge geometry to other more symmetrical strake-based vortex suppression systems commonly employed in infrastructure applications ranging from antennas to underwater gas and oil pipelines, we find that the unique maze-like ridge organization of E. aspergillum can completely suppress vortex shedding rather than delaying their shedding to a more downstream location, thus highlighting their potential benefit in these engineering contexts.
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Affiliation(s)
- Matheus C Fernandes
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.,Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA
| | - Mehdi Saadat
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Patrick Cauchy-Dubois
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - Chikara Inamura
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ted Sirota
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.,Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA
| | | | - Hossein Haj-Hariri
- College of Engineering and Computing, University of South Carolina, Columbia, SC 29208, USA
| | - Katia Bertoldi
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.,Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA
| | - James C Weaver
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.,Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA
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Saadat M, Berlinger F, Sheshmani A, Nagpal R, Lauder GV, Haj-Hariri H. Hydrodynamic advantages of in-line schooling. Bioinspir Biomim 2021; 16:046002. [PMID: 33513591 DOI: 10.1088/1748-3190/abe137] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 01/29/2021] [Indexed: 06/12/2023]
Abstract
Fish benefit energetically when swimming in groups, which is reflected in lower tail-beat frequencies for maintaining a given speed. Recent studies further show that fish save the most energy when swimming behind their neighbor such that both the leader and the follower benefit. However, the mechanisms underlying such hydrodynamic advantages have thus far not been established conclusively. The long-standing drafting hypothesis-reduction of drag forces by judicious positioning in regions of reduced oncoming flow-fails to explain advantages of in-line schooling described in this work. We present an alternate hypothesis for the hydrodynamic benefits of in-line swimming based on enhancement of propulsive thrust. Specifically, we show that an idealized school consisting of in-line pitching foils gains hydrodynamic benefits via two mechanisms that are rooted in the undulatory jet leaving the leading foil and impinging on the trailing foil: (i) leading-edge suction on the trailer foil, and (ii) added-mass push on the leader foil. Our results demonstrate that the savings in power can reach as high as 70% for a school swimming in a compact arrangement. Informed by these findings, we designed a modification of the tail propulsor that yielded power savings of up to 56% in a self-propelled autonomous swimming robot. Our findings provide insights into hydrodynamic advantages of fish schooling, and also enable bioinspired designs for significantly more efficient propulsion systems that can harvest some of their energy left in the flow.
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Affiliation(s)
- Mehdi Saadat
- Department of Organismal and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, United States of America
- Department of Mechanical Engineering, University of South Carolina, Columbia, South Carolina 29208, United States of America
| | - Florian Berlinger
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States of America
| | - Artan Sheshmani
- Center for Mathematical Sciences and Applications, Harvard University, Department of Mathematics, Cambridge, MA, 02139, United States of America
- Department of Mathematics, Aarhus University, Ny Munkegade 118, building 1530, 319, 8000 Aarhus C, Denmark
- National Research University Higher School of Economics, Russian Federation, Laboratory of Mirror Symmetry, NRU HSE, 6 Usacheva str., Moscow, Russia, 119048
| | - Radhika Nagpal
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States of America
| | - George V Lauder
- Department of Organismal and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, United States of America
| | - Hossein Haj-Hariri
- Department of Mechanical Engineering, University of South Carolina, Columbia, South Carolina 29208, United States of America
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Berlinger F, Saadat M, Haj-Hariri H, Lauder GV, Nagpal R. Fish-like three-dimensional swimming with an autonomous, multi-fin, and biomimetic robot. Bioinspir Biomim 2021; 16:026018. [PMID: 33264757 DOI: 10.1088/1748-3190/abd013] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
Fish migrate across considerable distances and exhibit remarkable agility to avoid predators and feed. Fish swimming performance and maneuverability remain unparalleled when compared to robotic systems, partly because previous work has focused on robots and flapping foil systems that are either big and complex, or tethered to external actuators and power sources. By contrast, we present a robot-the Finbot-that combines high degrees of autonomy, maneuverability, and biomimicry with miniature size (160 cm3). Thus, it is well-suited for controlled three-dimensional experiments on fish swimming in confined laboratory test beds. Finbot uses four independently controllable fins and sensory feedback for precise closed-loop underwater locomotion. Different caudal fins can be attached magnetically to reconfigure Finbot for swimming at top speed (122 mm s-1≡ 1 BL s-1) or minimal cost of transport (CoT = 8.2) at Strouhal numbers as low as 0.53. We conducted more than 150 experiments with 12 different caudal fins to measure three key characteristics of swimming fish: (i) linear speed-frequency relationships, (ii) U-shaped CoT, and (iii) reverse Kármán wakes (visualized with particle image velocimetry). More fish-like wakes appeared where the CoT was low. By replicating autonomous multi-fin fish-like swimming, Finbot narrows the gap between fish and fish-like robots and can address open questions in aquatic locomotion, such as optimized propulsion for new fish robots, or the hydrodynamic principles governing the energy savings in fish schools.
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Affiliation(s)
- F Berlinger
- Harvard University, John A. Paulson School of Engineering and Applied Sciences, Cambridge, MA 02138, United States of America
| | - M Saadat
- Department of Organismal and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States of America
| | - H Haj-Hariri
- College of Engineering and Computing, University of South Carolina, Columbia, SC 29208, United States of America
| | - G V Lauder
- Department of Organismal and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States of America
| | - R Nagpal
- Harvard University, John A. Paulson School of Engineering and Applied Sciences, Cambridge, MA 02138, United States of America
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Dehnavi H, Masoudi AA, Saadat M, Ghadiri H, Saffarzadeh A. Electron scattering in a superlattice of line defects on the surface of topological insulators. J Phys Condens Matter 2020; 32:415002. [PMID: 32521514 DOI: 10.1088/1361-648x/ab9b51] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
The electron scattering from periodic line defects on the surface of topological insulators with hexagonal warping effect is investigated theoretically by means of a transfer matrix method. The influence of surface line defects, acting as structural ripples on propagation of electrons are studied in two perpendicular directions due to the asymmetry of warped energy contour under momentum exchange. The transmission profiles and the details of resonant peaks which vary with the number of defects and the strength of their potentials are strongly dependent on the direction in which the line defects extend. At low energies, the quantum interference between the incident and reflected propagating electrons has the dominant contribution in transmission resonances, while at high energies the multiple scattering processes on the constant-energy contour also appear because of the strong warping effect. By increasing the spatial separation between the line defects, the minimum value of electrical conductance remains significantly high at low incident energies, while the minimum value may approach zero at high energies as the number of defects is increased. Our findings suggest that the potential ripples on the surface of topological insulators can be utilized to control the local electronic properties of these materials.
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Affiliation(s)
- H Dehnavi
- Department of Physics, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - A A Masoudi
- Department of Physics, Alzahra University, Tehran 1993891167, Iran
| | - M Saadat
- Department of Physics, Shahid Rajaee Teacher Training University, Tehran, Iran
| | - H Ghadiri
- Department of Physics, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - A Saffarzadeh
- Department of Physics, Payame Noor University, P.O. Box 19395-3697 Tehran, Iran
- Department of Physics, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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6
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Domel AG, Saadat M, Weaver JC, Haj-Hariri H, Bertoldi K, Lauder GV. Shark skin-inspired designs that improve aerodynamic performance. J R Soc Interface 2019; 15:rsif.2017.0828. [PMID: 29436512 DOI: 10.1098/rsif.2017.0828] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [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: 11/03/2017] [Accepted: 01/17/2018] [Indexed: 11/12/2022] Open
Abstract
There have been significant efforts recently aimed at improving the aerodynamic performance of aerofoils through the modification of their surfaces. Inspired by the drag-reducing properties of the tooth-like denticles that cover the skin of sharks, we describe here experimental and simulation-based investigations into the aerodynamic effects of novel denticle-inspired designs placed along the suction side of an aerofoil. Through parametric modelling to query a wide range of different designs, we discovered a set of denticle-inspired surface structures that achieve simultaneous drag reduction and lift generation on an aerofoil, resulting in lift-to-drag ratio improvements comparable to the best-reported for traditional low-profile vortex generators and even outperforming these existing designs at low angles of attack with improvements of up to 323%. Such behaviour is enabled by two concurrent mechanisms: (i) a separation bubble in the denticle's wake altering the flow pressure distribution of the aerofoil to enhance suction and (ii) streamwise vortices that replenish momentum loss in the boundary layer due to skin friction. Our findings not only open new avenues for improved aerodynamic design, but also provide new perspective on the role of the complex and potentially multifunctional morphology of shark denticles for increased swimming efficiency.
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Affiliation(s)
- August G Domel
- Harvard University John A. Paulson School of Engineering and Applied Sciences, Cambridge, MA 02138, USA
| | - Mehdi Saadat
- Department of Organismal and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.,College of Engineering and Computing, University of South Carolina, Columbia, SC 29208, USA
| | - James C Weaver
- Wyss Institute for Biologically Inspired Engineering, Cambridge, MA 02138, USA
| | - Hossein Haj-Hariri
- College of Engineering and Computing, University of South Carolina, Columbia, SC 29208, USA
| | - Katia Bertoldi
- Harvard University John A. Paulson School of Engineering and Applied Sciences, Cambridge, MA 02138, USA
| | - George V Lauder
- Department of Organismal and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
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7
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Domel AG, Domel G, Weaver JC, Saadat M, Bertoldi K, Lauder GV. Hydrodynamic properties of biomimetic shark skin: effect of denticle size and swimming speed. Bioinspir Biomim 2018; 13:056014. [PMID: 30018184 DOI: 10.1088/1748-3190/aad418] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Biomechanists and biologists alike have yet to fully understand the complex morphology and function of shark denticles, morphologically intricate tooth-like structures embedded into the skin of sharks. Denticles vary in many ways (such as size and shape) depending on shark species, and studies on denticle hydrodynamics have suggested that they may aid in drag reduction as well as increase both lift and thrust. Although previous studies have analyzed the effect of different denticle patterns on hydrodynamic performance, no previous work has focused on the effects of denticle size. Here, we report on the hydrodynamic properties of 3D printed shark skin foils with rigid denticles embedded into a flexible substrate. The patterning of these denticles was based on previously reported designs exhibiting the greatest hydrodynamic performance (which also most closely mimics real shark skin). The size of the denticles and the speed of the flow were varied, and the foils were evaluated under both static and dynamic conditions. Static tests showed drag reduction compared to a smooth control foil (without denticles) for the smallest denticle size, while medium and large denticles exhibited increased drag. Under dynamic testing conditions, the smallest denticles increased the self-propelled swimming speed, while the largest denticles reduced swimming performance. At higher speeds, the smallest denticles were also able to reduce power consumption compared to the control, demonstrating that their hydrodynamic effect depends on both denticle size and swimming speed. Our results thus provide new insights into the role of denticle size in shark swimming hydrodynamics across a range of locomotory modes, while simultaneously providing new design guidelines for the production of high performance low drag surface coatings for aquatic and aerospace applications.
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Affiliation(s)
- August G Domel
- Harvard University John A Paulson School of Engineering and Applied Sciences, Cambridge, MA 02138, United States of America
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Afarideh M, Ghajar A, Noshad S, Saadat M, Khajeh E, Esteghamati A. Serum 25-hydroxyvitamin D, non-alcoholic fatty liver disease and type 2 diabetes. Nutr Metab Cardiovasc Dis 2017; 27:93-95. [PMID: 27986351 DOI: 10.1016/j.numecd.2016.09.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 09/05/2016] [Accepted: 09/14/2016] [Indexed: 12/31/2022]
Affiliation(s)
- M Afarideh
- Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
| | - A Ghajar
- Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
| | - S Noshad
- Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
| | - M Saadat
- Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
| | - E Khajeh
- Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
| | - A Esteghamati
- Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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Saadat M, Nezamzadeh-Ejhieh A. Clinoptilolite nanoparticles containing HDTMA and Arsenazo III as a sensitive carbon paste electrode modifier for indirect voltammetric measurement of Cesium ions. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.09.084] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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10
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Pul R, Saadat M, Morbiducci F, Skripuletz T, Pul Ü, Brockmann D, Sühs KW, Schwenkenbecher P, Kahl KG, Pars K, Stangel M, Trebst C. Longitudinal time-domain optic coherence study of retinal nerve fiber layer in IFNβ-treated and untreated multiple sclerosis patients. Exp Ther Med 2016; 12:190-200. [PMID: 27347038 PMCID: PMC4906774 DOI: 10.3892/etm.2016.3300] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 02/11/2016] [Indexed: 12/14/2022] Open
Abstract
Quantification of the retinal nerve fiber layer (RNFL) by optical coherence tomography (OCT) has been proposed to provide an indirect measure for retinal axonal loss. The aim of the present study was to determine whether interferon beta (IFNβ) treatment impedes retinal axonal loss in multiple sclerosis (MS) patients. A total of 48 patients with MS (24 IFNβ-1b-treated and 24 untreated subjects) and 12 healthy controls were enrolled in a prospective longitudinal OCT study. OCT measurements were performed for both eyes of each subject at baseline, and at 3-, 6-, and 12-month follow-up examinations using a time-domain OCT. At each visit, we additionally recorded full-field visual evoked potential (VEP) responses and performed the paced auditory serial addition test (PASAT), in addition to expanded disability status scale (EDSS) scoring. Generalized estimation equation (GEE) was used to account for repeated measurements and paired-data. The model-based approach predicted a monthly reduction in the RNFL thickness by 0.19 µm in the eyes of the MS subjects. The reduction was estimated to be 0.17 µm in case of IFNβ-treatment and 0.16 µm in case of no treatment. Treatment duration and group allocation were not significantly associated with the RNFL thickness. Inclusion of further longitudinal data (EDSS, two and three second PASAT) in each of our models did not result in any significant association. In summary, over a period of one year no significant association between IFNβ-1b treatment and RNFL thinning was identified in patients with MS.
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Affiliation(s)
- Refik Pul
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Mehdi Saadat
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Franco Morbiducci
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Thomas Skripuletz
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Ünsal Pul
- Department of Thoracic and Cardiovascular Surgery, University Hospital Essen, 45147 Essen, Germany
| | - Dorothee Brockmann
- Department of Ophthalmology, Hannover Medical School, 30625 Hannover, Germany
| | - Kurt-Wolfram Sühs
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | | | - Kai Günter Kahl
- Department of Psychiatry, Hannover Medical School, 30625 Hannover, Germany
| | - Kaweh Pars
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Martin Stangel
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Corinna Trebst
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
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Ahdenov R, Mohammadi AA, Taheri S, Ghaderi P, Saadat M. An Efficient Synthesis for Some New Heterocyclic Compound-fused Oxindole Derivatives. J Heterocycl Chem 2015. [DOI: 10.1002/jhet.2560] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- R. Ahdenov
- Chemistry and Chemical Engineering Research Center of Iran (CCERCI); PO Box 14335-186 Tehran Iran
| | - A. A. Mohammadi
- Chemistry and Chemical Engineering Research Center of Iran (CCERCI); PO Box 14335-186 Tehran Iran
| | - S. Taheri
- Chemistry and Chemical Engineering Research Center of Iran (CCERCI); PO Box 14335-186 Tehran Iran
| | - P. Ghaderi
- Chemistry and Chemical Engineering Research Center of Iran (CCERCI); PO Box 14335-186 Tehran Iran
| | - M. Saadat
- Chemistry and Chemical Engineering Research Center of Iran (CCERCI); PO Box 14335-186 Tehran Iran
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Mobini A, Behzadipour S, Saadat M. Test-retest reliability of Kinect's measurements for the evaluation of upper body recovery of stroke patients. Biomed Eng Online 2015; 14:75. [PMID: 26238199 PMCID: PMC4523016 DOI: 10.1186/s12938-015-0070-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [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: 04/12/2015] [Accepted: 07/21/2015] [Indexed: 11/10/2022] Open
Abstract
Background Performance indices provide quantitative measures for the quality of motion, and therefore, assist in analyzing and monitoring patients’ progress. Measurement of performance indices requires costly devices, such as motion capture systems. Recent developments of sensors for game controllers, such as Microsoft Kinect, have motivated many researchers to develop affordable systems for performance measurement applicable to home and clinical care. In this work, the capability of Kinect in finding motion performance indices was assessed by analyzing intra-session and inter-session test–retest reliability. Method Eighteen stroke patients and twelve healthy subjects participated in this investigation. The intra-session and inter-session reliability of eight performance indices, namely mean velocity (MV), normalized mean speed (NMS), normalized speed peaks (NSP), logarithm of dimensionless jerk (LJ), curvature (C), spectral arc length (SAL), shoulder angle (SA), and elbow angle (EA), were assessed using intra-class correlation coefficient (ICC), standard error of measurement (SEM) and coefficient of variation (CV). Results The results showed that, among the performance indices, MV, LJ, C, SA and EA have more than 0.9 ICC together with an acceptable SEM and CV in both stroke patients and healthy subjects. Comparing the results of different therapy sessions showed that MV, LJ and C are more sensitive than other indices, and hence, more capable of reflecting the progress of a patient during the rehabilitation process. Conclusion The results of this study shows acceptable reliability and sensitivity across the sessions for MV, LJ and C measured by Kinect for both healthy subjects and stroke patients. The results are promising for the development of home-based rehabilitation systems, which can analyze patient’s movements using Kinect as an affordable motion capture sensor.
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Affiliation(s)
- A Mobini
- Mechanical Engineering Department, Sharif University of Technology, Tehran, Iran.
| | - S Behzadipour
- Mechanical Engineering Department, Sharif University of Technology, Tehran, Iran.
| | - M Saadat
- Mechanical Engineering Department, Sharif University of Technology, Tehran, Iran.
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Shaterzadeh M, Saadat M, Arastoo A, Zahednezhad S, Negahban H. The effect of allocation of attentional resources on postural control in individuals with chronic nonspecific neck pain. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.1314] [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: 10/23/2022]
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Sadeghi Aval Shahr H, Saadat M, Kheirkhah M, Saadat E. The effect of self-aromatherapy massage of the abdomen on the primary dysmenorrhoea. J OBSTET GYNAECOL 2014; 35:382-5. [DOI: 10.3109/01443615.2014.958449] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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15
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Saadat M. Association between QTc of patients with schizophrenia and five genetic polymorphisms of GSTZ1 and XRCC1. Heart Asia 2014; 6:8-9. [DOI: 10.1136/heartasia-2013-010424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Accepted: 11/04/2013] [Indexed: 11/04/2022]
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Khosravi M, Saadat I, Karimi MH, Geramizadeh B, Saadat M. Glutathione S-transferase Omega 2 Genetic Polymorphism and Risk of Hepatic Failure that Lead to Liver Transplantation in Iranian Population. Int J Organ Transplant Med 2013; 4:16-20. [PMID: 25013648 PMCID: PMC4089303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Liver transplantation is the treatment of choice for both acute and chronic hepatic failure. GSTs family is one of the most important genes in phase II detoxification interfering with the xenobiotics and free radical metabolism. GSTO2 (N142D) is a member of this family the polymorphism of which may influence the metabolism of active components and free radicals and may contribute to hepatic failure. OBJECTIVE To investigate the association between GSTO2 genetic polymorphism and the susceptibility of hepatic failure that would lead to liver transplantation. METHODS This case-control study included 330 healthy people and 302 patients with liver transplantation as a result of hepatic failure. To determine the variants of GSTO2, we used polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS There was a significant association between D allele and hepatic failure, thus, people with DD genotype are more susceptible to develop heaptic failure leading to liver transplantation (OR=1.8, 95% CI: 1.10-2.95, p=0.02). We also observed that male sex increases the chance of hepatic failure (OR=2.69, 95% CI: 1.95-3.71, p=0.001). CONCLUSION D allele may reduce the detoxification ability of liver so people with mutant D allele are more prone to develop hepatic failure.
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Affiliation(s)
- M. Khosravi
- Department of Biology, College of Sciences, Shiraz University, Shiraz 71454, Iran
| | - I. Saadat
- Department of Biology, College of Sciences, Shiraz University, Shiraz 71454, Iran,Institute of Biotechnology, Shiraz University, Shiraz, Iran,Correspondence: Iraj Saadat, Department of Biology, College of Sciences, Shiraz University, Shiraz 71454, Iran, E-mail:
| | - M. H. Karimi
- Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - B. Geramizadeh
- Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M. Saadat
- Department of Biology, College of Sciences, Shiraz University, Shiraz 71454, Iran,Institute of Biotechnology, Shiraz University, Shiraz, Iran
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Whitehouse K, Ranjan J, Lu J, Sookoor T, Saadat M, Burke CM, Staengl G, Canfora A, Haj-Hariri H. Towards Occupancy-Driven Heating and Cooling. ACTA ACUST UNITED AC 2012. [DOI: 10.1109/mdt.2012.2201439] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Ghasemzadeh A, Karami S, Saadat M, Mazaheri E, Zandipour T. P-482 - Effects of group counseling with cognitive-behavioural approach on reducing divorce children's depression. Eur Psychiatry 2012. [DOI: 10.1016/s0924-9338(12)74649-7] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Ghasemzadeh A, Saadat M, Mazaheri E, Karami S. P-856 - Self-esteem in iranian university student and it's relationship with academic achievement. Eur Psychiatry 2012. [DOI: 10.1016/s0924-9338(12)75023-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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Abstract
BACKGROUND The pathogenesis of cataract is influenced by a number of factors including oxidative stress. Glutathione S-transferase (GST) catalyses the nucleophilic addition of the thiol of GST to electrophilic acceptors. It is important for detoxification of xenobiotics in order to protect tissues from oxidative damage. OBJECTIVES To examine whether the interaction of polymorphism of GSTM1 gene and occupational sunlight exposure modulate the risk of cataract. METHODS Blood samples from 95 subjects with cataract and 95 age and sex matched healthy persons were collected. The genotypes of GSTM1 were determined using PCR. RESULTS The null genotype of GSTM1 was associated with an increase in cataract risk in the indoor workplace, but this association was not significant in the outdoor subjects. CONCLUSION The active genotype of GSTM1 has lost its protective role in persons who work outdoors. It is suggested that activity of the GSTmu enzyme may be inhibited in the human lens after occupational exposure to UV light.
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Affiliation(s)
- M Saadat
- Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran.
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Saadat M, Kikuchi K. Assignment of the gene encoding magnesium-dependent protein phosphatase 1alpha (PPM1A) to human chromosome 14q22-->q23 and rat chromosome 6q24 by fluorescence in situ hybridization. Cytogenet Genome Res 2005; 108:363. [PMID: 15628034 DOI: 10.1159/000081538] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- M Saadat
- Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran
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Abstract
Consanguineous marriage is a major feature of family systems in south-west Asia. The aim of the present study was to determine the current prevalence and patterns of consanguinity in Iran as a means of assessing the associated requirement for genetic counselling services. Consanguinity was studied in 12 ethnic/religious populations, the Persians (Shi'a and Sunni), Kurds (Shi'a and Sunni), Lurs, Azaris, Baluchis, Zabolis, Turkamans, Bakhtiaris, Ghashghais and Arabs. A multi-stage sampling design was used with a representative total sample of 306 343 couples. The overall rate of consanguineous marriage was 38.6% with a mean inbreeding coefficient (alpha) of 0.0185. First cousin marriages (27.9%) were the most common form of consanguineous union, with parallel patrilateral marriage especially favoured. Statistically significant differences were observed in the prevalence and patterns of consanguinity between ethnic/religious populations and geographical regions. There also were significant differences for proportions of consanguineous marriages between Shi'a and Sunni populations within the same ethnic group. The highest rates of consanguineous union were in the least affluent sections of the population.
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Affiliation(s)
- M Saadat
- Department of Biology, College of Sciences, Shiraz University, Iran.
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Abstract
The aim of this study was to investigate whether the occupational exposure to gasoline of men employed at filling stations affects the sex of their children. Altogether 115 offspring (47 males, 68 females) were identified within families of 49 men working in filling stations in Shiraz (Fars province, south of Iran) and 345 offspring (178 males, 167 females) from 147 families of unexposed persons from the general population of Shiraz, which were matched by age of fathers (+/-2 years) and number of children as a control group. The offspring sex ratio at birth (male proportion) in the filling station workers was significantly lower than the ratio in control group (OR = 0.65; 95% confidence intervals (CI) 0.42 to 0.99). Genotypes of glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) were investigated on extracted genomic DNA of 37 exposed workers using the polymerase chain reaction based method. In exposed group with active GSTM1 and GSTT1 genes, offspring sex ratio was the same as the ratio in the control group (OR = 0.66; 95% CI 0.34 to 1.28). However, in the exposed group with active GSTM1 and null genotype of GSTT1, the offspring sex ratio statistically decreased (OR = 0.45; 95% CI = 0.21 to 0.96). It seems that the GSTT1 null genotype has an effect on offspring sex ratio in the filling station workers.
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Affiliation(s)
- M Ansari-Lari
- Department of Community Medicine, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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Affiliation(s)
- M Ansari-Lari
- Department of Community Medicine, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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Abstract
Several polymorphic glutathione S-transferase (GST) enzymes are involved in the detoxification of active metabolites of many potential carcinogens and may therefore be important in modulating susceptibility to cancers. GSTM1 and GSTT1 are polymorphic, and the null alleles result in a lack of corresponding enzyme activities. Previous studies demonstrated that the GSTM1 and GSTT1 null genotypes correlated with an increased risk of developing some cancers. In this study, we determined GSTM1 and GSTT1 polymorphisms in a population of 131 healthy controls from the south of Iran, 46 patients with colorectal cancers, and 42 patients with gastric cancer. The gastric cancer risk statistically increased due to the GSTM1 null genotype (odds ratio (OR)=2.3, 95% confidence interval (CI): 1.15--4.95). On the other hand, the GSTT1 null genotype in gastric cancer and null genotypes of GSTM1 and GSTT1 in colorectal cancer were not statistically significant. Moreover, individuals showing the GSTM1 and GSTT1 null genotypes might exhibit a greater predisposition to gastric (OR=3.31, 95% CI: 1.14--9.57) and colorectal (OR=2.73, 95% CI: 0.94--7.95, P=0.07) cancers.
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Affiliation(s)
- I Saadat
- Department of Biology, College of Sciences, Shiraz University, Shiraz 71454, Iran
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Abstract
Twenty micro medullary thyroid carcinomas (MTCs) were found in histologic specimens of 19 patients in our department from 1990 to 1998. There were 14 women and 5 men, with a median age of 63 years. The indication for surgery was goiter in 12 patients and a solitary nodule in 7 patients (three differentiated cancers). Altogether, 18 patients had unifocal micro-MTCs with a median diameter of 3.6 mm. One patient had a bilateral MTC (3 and 5 mm, respectively). Surgical procedures consisted of 9 total thyroidectomies and 10 lobectomies or subtotal thyroidectomies. Of these 10 patients, 4 underwent reoperation (totalization). One was operated on 48 months after a positive pentagastrin test: There was no thyroid residual tumor but three lymph node micrometastases. Among the six patients in whom thyroid tissue was left, a 91-year-old woman died of unrelated cause and the five others remain disease-free without biologic abnormalities at follow-ups of 18 to 70 months. Considering the aggressiveness of MTCs, total thyroidectomy with central compartment dissection is theoretically indicated. However, among the nine total thyroidectomies and four secondary totalizations associated with at least central compartment dissection, no other thyroid lesion was observed and only one case of lymph node microinvasion was found. Because of the morbidity associated with reoperation and neck dissection, we propose that it is indicated only for microcarcinomas > 5 mm in diameter, in cases of an abnormal response to pentagastrin, or when it is difficult to ensure prolonged follow-up of the patient.
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Affiliation(s)
- J L Peix
- Department of Surgery, Hôpital de l'Antiquaille, 69321 Lyon Cédex 05, France
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Abstract
It has been postulated that the absence of glutathione S-transferase mu (GSTmu), which impairs detoxification of some carcinogens, might predispose some individuals to the development of certain cancers. In the present study, polymorphism of GSTM1 were detected by polymerase chain reaction (PCR) in 38 patients with acute lymphocytic leukemia and 75 normal subjects. The null genotype of GSTM1 was significantly more common among leukemic patients compared with the normal control group (55.3 vs. 32.0%; P<0.025). The absence of the GSTmu enzyme may increase the risk of the development of leukemia.
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Affiliation(s)
- I Saadat
- Department of Biology, College of Sciences, Shiraz University, 71454, Shiraz, Iran
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Abstract
The aim of this study was to evaluate in breast cancer patients the feasibility of sentinel lymph node (SLN) identification and the sensitivity of this technique to detect node metastases. Between January and July 1997, SLNs were tracked with Evans Blue dye in 100 patients with breast cancer who then underwent complete level I/II axillary lymph node dissection (ALND). All SLNs were examined by haematoxylin-phloxin-saffron (HPS) staining and immunohistochemistry (IHC) of multiple sections. The findings for the SLNs were compared with results on ANLD. Axillary SLNs were identified in 83 patients (detection rate = 83%; 95% confidence interval (CI) 74-90%). Axillary SLNs were detected in 58/83 cases (70%) at level I only, and in 69/83 (83%) at levels including level I. Histologically positive axillary SLNs were found in 45% (37/83) of patients, including 2 patients with malignancy (micro-metastases) detected by IHC only. The sensitivity of axillary SLN to detect axillary lymph nodes metastases was 37/39 = 95% (95% CI 83-99%). SLNs of the internal mammary chain (IMC) were dissected for 33 tumours of the median or inner quadrants and detected in 26/33 = 79% of cases (95% CI 61-91%). In our experience, the overall sensitivity of SLN identification as a predictor of node (axillary or IMC) metastases was 41/43 = 95% (95% CI 84-99%), confirming the usefulness of the procedure.
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Affiliation(s)
- J Y Bobin
- Department of Surgical Oncology, Centre Hospitalier Lyon-Sud, France
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Kikuchi K, Kitamura K, Kakinoki Y, Nakamura K, Matsuzawa S, Saadat M, Mizuno Y. Gene expressions and activities of protein phosphatases 1 alpha, 2A and 2C in hepatocarcinogenesis and regeneration after partial hepatectomy. Cancer Detect Prev 1997; 21:36-43. [PMID: 9043761] [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: 02/03/2023]
Abstract
The mRNA levels of protein phosphatases (PP) 1 alpha, 2A, and 2C were determined both in hepatocarcinogenesis and in liver regeneration. In the precancerous stage and during regeneration, the mRNA levels of PP1 alpha, PP2A, and PP2C were markedly increased compared with those in normal livers. In primary hepatomas, all three of these mRNA levels were decreased to the control levels. In poorly differentiated hepatomas, however, only PP1 alpha mRNA was specifically increased, in contrast to PP2A and PP2C, which were at the control levels or below. While PP1 activity in the non-nuclear fraction of partially hepatectomized livers was nearly constant, the activity in nuclei was increased about 2.5-fold over control levels at 12 h after partial hepatectomy, the time that corresponds to the G1 to S transition in the cell cycle of hepatocytes. On the other hand, PP2A activity in both fractions was nearly constant throughout. These results appear to suggest some involvement of protein phosphatases in regulation of hepatocyte proliferation.
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Affiliation(s)
- K Kikuchi
- Section of Biochemistry, Hokkaido University, Japan
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Saadat M, Nomoto K, Mizuno Y, Kikuchi K, Yoshida MC. Assignment of the gene encoding type 1 gamma protein phosphatase catalytic subunit (PPP1CC) on human, rat, and mouse chromosomes. Jpn J Hum Genet 1996; 41:159-65. [PMID: 8914631 DOI: 10.1007/bf01892623] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Using fluorescent in situ hybridization (FISH) method, a gene encoding the catalytic subunit of protein phosphatase type 1 gamma (PPP1CC) was mapped to human 12q24.1-q24.2, rat 7 q22, and mouse 10C. These results indicate that the PPP1CC is a member of conserved synteny group between rat chromosome 7, mouse chromosome 10 and human chromosome 12. These data and mapping data about other members of PP1 family show that in spite of the high identity of PP1 isoforms, each isoform is encoded by different genes which located on different chromosomes in human, rat, and mouse.
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Affiliation(s)
- M Saadat
- Section of Biochemistry, Hokkaido University, Sapporo, Japan
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Abstract
The authors attempt to assess the relationship between exercise, diabetes, and bone metabolism. An animal model system was developed to study the relationship. Animals given streptozotocin to induce a type I diabetic state show elevated plasma glucose and triglyceride levels and a decrease in body weight. Analysis of femurs revealed alterations in copper, phosphorus, and zinc levels in animals with diabetes compared with controls. Mineral analysis of femurs from diabetic animals placed on an exercise regimen revealed values closer to control levels.
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Affiliation(s)
- J P Burke
- Biochemistry, Pennsylvania College of Podiatric Medicine, Philadelphia 19107, USA
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Saadat M, Nakamura K, Mizuno Y, Kikuchi K, Yoshida MC. Regional localization of rat and mouse protein-tyrosine phosphatase PTP alpha/LRP gene (Ptpra) by fluorescence in situ hybridization. Jpn J Genet 1995; 70:669-74. [PMID: 8790445 DOI: 10.1266/jjg.70.669] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Protein tyrosine phosphatases (PTPases) negatively regulate the effect(s) of protein tyrosine kinases and are implicated in the regulation of a variety of biological events including cell activation, differentiation, and neoplastic transformation. To gain insight into the role(s) of the PTPases, we mapped the gene encoding for the widely expressed receptor-like protein tyrosine phosphatase PTP alpha/LRP (locus symbol Ptpra) to rat chromosome 3q36 and mouse chromosome 2G by fluorescence in situ hybridization method. These results indicate that there is a conserved syntenic group between human 20p13, rat 3q36, and mouse 2G.
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Affiliation(s)
- M Saadat
- Department of Biology, Faculty of Science, Shiraz University, Iran
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Saadat M, Mizuno Y, Takizawa N, Kakinoki Y, Rikuchi R. Neoplastic alterations in subcellular distribution of type 1 alpha protein phosphatase in rat ascites hepatoma cells. Cancer Lett 1995; 94:165-70. [PMID: 7634244 DOI: 10.1016/0304-3835(95)03846-o] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [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: 01/26/2023]
Abstract
Neoplastic alterations of type 1 alpha protein phosphatase (PP1 alpha) have been studied in rat ascites hepatoma cells, using regenerating liver after partial hepatectomy and normal rat liver as controls. In the particulate fraction of hepatomas, potential PP1 activity and the amount of PP1 alpha were remarkably increased compared with either regenerating or normal livers. In the nuclear fraction, PP1 activity and the amount of PP1 alpha were increased in hepatoma compared with the controls. The nuclear PP1 activity in hepatomas was activated by treatment with CO2+/trypsin, whereas that of normal or regenerating liver was not activated. These characteristic alterations of PP1 alpha in its amount and subcellular distribution may be implicated in malignant phenotype(s) such as uncontrolled cell growth.
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Affiliation(s)
- M Saadat
- Section of Biochemistry, Hokkaido University, Sapporo, Japan
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Saadat M, Mizuno Y, Kikuchi K, Yoshida MC. Comparative mapping of the gene encoding the catalytic subunit of protein phosphatase type 1 alpha (PPP1CA) to human, rat, and mouse chromosomes. Cytogenet Cell Genet 1995; 70:55-7. [PMID: 7736790 DOI: 10.1159/000133991] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Using fluorescence in situ hybridization method, the gene encoding the protein phosphatase type 1 alpha catalytic subunit (PPP1CA) was localized to human chromosome band 11q13, rat chromosome band 1q43, and mouse chromosome band 7E3-F2. These results suggest that PPP1CA is a member of a syntenic group.
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Affiliation(s)
- M Saadat
- Section of Biochemistry, Hokkaido University, Sapporo, Japan
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Saadat M, Kakinoki Y, Mizuno Y, Kikuchi K, Yoshida MC. Chromosomal localization of human, rat, and mouse protein phosphatase type 1 beta catalytic subunit genes (PPP1CB) by fluorescence in situ hybridization. Jpn J Genet 1994; 69:697-700. [PMID: 7857673 DOI: 10.1266/jjg.69.697] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Using fluorescent in situ hybridization (FISH) method, gene encoding the catalytic subunit of protein phosphatase type 1 beta (PPP1CB) in human and its corresponding gene in rat (PP1 delta) and mouse (dis2m2) were mapped to human 2p23, rat 6q21-q23, and mouse 12D, respectively. These results indicate that PPP1CB is a member of conserved syntenic group. It is shown that the genes encoding catalytic subunit of protein phosphatase type 1 family (PP1 alpha, PP1 beta, and PP1 gamma in human and those corresponding genes in rat and mouse), in spite of their high identity, are located to different chromosomes in these three species.
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Affiliation(s)
- M Saadat
- Section of Biochemistry, Faculty of Science, Hokkaido University, Sapporo, Japan
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Abstract
The amounts of four isoforms of the catalytic subunit of type-1 protein phosphatases, PP1 alpha, PP1 gamma 1, PP1 gamma 2, and PP1 delta, have been determined in extracts of rat ascites hepatomas, AH131A, AH13, AH13NMOR, AH143A, and Yoshida sarcoma, and compared to those of rat liver by Western blot analysis. The amount of PP1 alpha was increased over three times in all five hepatomas. The amount of PP1 gamma 1 was increased over two times in AH13, AH13NMOR, and AH143A. The amount of PP1 delta was selectively increased about 4 times in AH131A and AH143A. The PP1 gamma 2 protein was undetectable in both liver and hepatomas. There was good parallelism between the general increase in only PP1 alpha protein in the hepatomas and the previous data demonstrating the general increase in PP1 alpha mRNA in numerous ascites hepatomas. These results suggest that PP1 alpha plays important roles in the expression of malignant phenotype, that its amount is under strict control at the transcription level, and that PP1 gamma 1 and PP1 delta play different roles in the expression of some phenotype(s) of the ascites hepatomas.
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Affiliation(s)
- N Takizawa
- Section of Biochemistry, Hokkaido University
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Abstract
The study compares changes in the accuracy of the diagnosis of pregnancy in adolescents between 1965 and 1980. We compared 44 records of adolescents evaluated in 1965 to those of 44 who were evaluated 15 years later in 1980. The following data were examined: (1) reason for consultation, (2) amount of time prior to making the correct diagnosis, and (3) the most common diagnostic errors. The results showed that (1) the initial diagnosis was correct only 75 per cent of the time in 1965 and 86 per cent in 1980, (2) both in 1965 and 1980 most patients initially consulted for "vague complaints," (3) in 1965 and 1980 the most common diagnostic errors were "gastrointestinal disorder" and "functional symptoms," and (4) pregnancy was diagnosed earlier in 1980 than in 1965. Improvement in diagnostic accuracy should be possible if clinicians screen for pregnancy in adolescent girls consulting for vague symptoms such as nausea, weight gain, urticaria, and somnolence.
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Saadat M, Khan MA, Gutherlet RL, Heald FP. Measurements of hair in normal newborns. Pediatrics 1976; 57:960-2. [PMID: 934753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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